FREQ Frequency Therapeutics Inc

Exhibit 3.1

CERTIFICATE OF AMENDMENT

TO

RESTATED CERTIFICATE OF INCORPORATION

OF

FREQUENCY THERAPEUTICS, INC.

Frequency Therapeutics, Inc., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “Corporation”), does hereby certify as follows:

RESOLVED, that the first sentence of Article FOURTH of the Restated Certificate of Incorporation be, and hereby is, amended and restated in its entirety to read as follows:

“That on the date this Certificate of Amendment to the Restated Certificate of Incorporation is filed with the Secretary of State of the State of Delaware (the “Effective Time”), a one-for-fifty reverse stock split of the Common Stock (as defined below) shall become effective, pursuant to which each fifty shares of Common Stock issued and held of record by each stockholder of the Corporation (including treasury shares) immediately prior to the Effective Time shall be reclassified and combined into one validly issued, fully paid and nonassessable share of Common Stock automatically and without any action by the holder thereof upon the Effective Time and shall represent one share of Common Stock from and after the Effective Time (such reclassification and combination of shares, the “Reverse Stock Split”). No fractional shares of Common Stock shall be issued as a result of the Reverse Stock Split and, in lieu thereof, (a) with respect to holders of one or more certificates, if any, which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, upon surrender after the Effective Time of such certificate or certificates, any holder who would otherwise be entitled to a fractional share of Common Stock as a result of the Reverse Stock Split, following the Effective Time, shall be entitled to receive a cash payment (the “Fractional Share Payment”) equal to the fraction of which such holder would otherwise be entitled multiplied by the closing price per share of Common Stock on the date of the Effective Time as reported by The Nasdaq Global Select Market (as adjusted to give effect to the Reverse Stock Split); provided that, whether or not fractional shares would be issuable as a result of the Reverse Stock Split shall be determined on the basis of (i) the total number of shares of Common Stock that were issued and outstanding immediately prior to the Effective Time formerly represented by certificates that the holder is at the time surrendering and (ii) the aggregate number of shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificates shall have been reclassified; and (b) with respect to holders of shares of Common Stock in book-entry form in the records of the Corporation’s transfer agent that were issued and outstanding immediately prior to the Effective Time, any holder who would otherwise be entitled to a fractional share of Common Stock as a result of the Reverse Stock Split (after aggregating all fractional shares), following the Effective Time, shall be entitled to receive the Fractional Share Payment automatically and without any action by the holder.

The total number of shares of all classes of stock which the Corporation shall have authority to issue is 210,000,000 shares, consisting of (a) 200,000,000 shares of Common Stock, $0.001 par value per share (“Common Stock”), and (b) 10,000,000 shares of Preferred Stock, $0.001 par value per share (“Preferred Stock”).”

IN WITNESS WHEREOF, the Corporation has caused this Certificate of Amendment to be signed by a duly authorized officer of the Corporation on this 3^rd day of November, 2023.

Exhibit 3.2

CERTIFICATE OF AMENDMENT

TO

RESTATED CERTIFICATE OF INCORPORATION

OF

FREQUENCY THERAPEUTICS, INC.

Frequency Therapeutics, Inc., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “Corporation”), does hereby certify as follows:

FIRST: That the name of the corporation is Frequency Therapeutics, Inc. The Corporation was originally incorporated pursuant to the General Corporation Law of the State of Delaware (the “DGCL”) on November 13, 2014.

SECOND: Article FIRST of the Corporation’s Restated Certificate of Incorporation (the “Restated Certificate”), is hereby amended and restated to read in its entirety as follows:

FIRST: The name of the corporation is Korro Bio, Inc. (the “Corporation”).

THIRD: In accordance with the provisions of Section 141(f) and 242 of the DGCL the foregoing amendment to the Restated Certificate has been duly adopted and declared advisable by the Board of Directors of the Corporation.

FOURTH: This Certificate of Amendment shall become effective upon filing with the Secretary of State of the State of Delaware.

IN WITNESS WHEREOF, this Certificate of Amendment has been executed by a duly authorized officer of the Corporation on this 3^rd day of November, 2023.

Exhibit 10.1

SUBSCRIPTION AGREEMENT

This Subscription Agreement (this “Agreement”) is made and entered into as of July 14, 2023 (the “Effective Date”) by and among Korro Bio, Inc., a Delaware corporation (the “Company”), and each of the purchasers listed on the signature pages hereto, severally and not jointly (each a “Purchaser” and together the “Purchasers”). Certain terms used and not otherwise defined in the text of this Agreement are defined in Section 8 hereof.

RECITALS

WHEREAS, the Company is party to that certain Agreement and Plan of Merger by and among the Company, Frequency Merger Sub Inc. (“Merger Sub”), and Frequency Therapeutics, Inc. (“Frequency”), dated on or about the date hereof (the “Merger Agreement”), pursuant to which the Company will merge with and into Merger Sub and become a wholly-owned subsidiary of Frequency (the “Merger”);

WHEREAS, following the Effective Time (as defined in the Merger Agreement), Frequency will change its name to Korro Bio, Inc.;

WHEREAS, the Company desires to sell to the Purchasers, and the Purchasers, severally and not jointly, desire to purchase from the Company, an aggregate amount equal to $117,249,989 of shares of the Company’s Common Stock, par value $0.001 per share (the “Common Stock”);

WHEREAS, the Company and each Purchaser is executing and delivering this Agreement in reliance upon the exemption from securities registration afforded by Section 4(a)(2) of the 1933 Act and not in reliance upon any of the safe harbors set forth in Regulation D thereunder; and

WHEREAS, at the Effective Time (as defined in the Merger Agreement) by virtue of the Merger, the Securities (as defined below) shall be automatically converted into the right to receive a number of shares of common stock, par value $0.001 per share, of Frequency (the “Merger Shares”) equal to the Exchange Ratio (as defined in the Merger Agreement) as provided in the Merger Agreement.

NOW, THEREFORE, in consideration of the foregoing and the mutual representations, warranties and covenants herein contained, the parties hereto hereby agree as follows:

SECTION 1. Authorization of Securities.

1.01 The Company has authorized the sale and issuance of shares of Common Stock on the terms and subject to the conditions set forth in this Agreement. The shares of Common Stock sold hereunder at the Closing (as defined below) shall be referred to as the “Securities”.

SECTION 2. Sale and Purchase of the Securities.

2.01 Upon the terms and subject to the conditions herein contained, the Company agrees to sell and issue to each Purchaser, and each Purchaser agrees, severally and not jointly, to purchase from the Company, at a closing to take place remotely, subject to the satisfaction or waiver of the closing conditions set forth in Section 6, via exchange of executed documents (the “Closing” and the date of the Closing, the “Closing Date”) to occur immediately prior to the Effective Time (as defined in the Merger Agreement) and conditioned upon the satisfaction or waiver of all conditions to the consummation of the Merger and the condition subsequent of the consummation of the Merger, that number of Securities (the “Closing Shares”) set forth opposite such Purchaser’s name on the Schedule of Purchasers for the aggregate Purchase Price set forth under the heading “Subscription Amount” (subject to adjustment for any stock split, reverse stock split or similar recapitalization transaction effected after the Effective Date and prior to the Closing, in accordance with Section 9.18 hereof).

2.02 At or prior to the Closing, each Purchaser will pay the subscription amount set forth opposite such Purchaser’s name on the Schedule of Purchasers (the “Subscription Amount”) by wire transfer of immediately available funds in accordance with wire instructions provided by the Company to the Purchasers at least three Business Days prior to the Closing (the “Wire Instructions Notice”), which Wire Instructions Notice shall

include an express acknowledgement that the Company reasonably expects all conditions to the closing of the Merger under the Merger Agreement to be satisfied on the Closing Date. If so requested by the Company in the Wire Instructions Notice and agreed by the applicable Purchaser, the Subscription Amount of each Purchaser shall be paid into an escrow fund or trust account designated by the Company in writing (the “Escrow Account”) to be released to the Company only upon satisfaction of each of the closing conditions set forth in Section 6 hereof. In the event the Closing does not occur within three Business Days of the Closing Date specified in the Wire Instructions Notice, unless otherwise agreed by the Company and such Purchaser, the Company shall, or shall cause the escrow agent for the Escrow Account to, promptly (but not later than one Business Day thereafter) return the Subscription Amount to each Purchaser by wire transfer of U.S. dollars in immediately available funds to the account specified by such Purchaser; provided that, unless this Agreement has been terminated pursuant to Section 9.13 hereof, such return of funds shall not terminate this Agreement or relieve the Company of its obligation to issue and sell, or of each Purchaser to purchase the Securities at the Closing. On the Closing Date, the Company will deliver, against payment by each Purchaser of its Subscription Amount, the Closing Shares in book-entry form registered in the name of the Purchaser (or its nominee as instructed by the Purchaser) free and clear of any liens or other restrictions (other than those arising under applicable securities laws) in the name of such Purchaser (or its nominee in accordance with such Purchaser’s delivery instructions) on the Company’s share register, and shall provide evidence of such issuance as of the Closing Date to each Purchaser. Notwithstanding anything to the contrary in this Agreement, each Purchaser acknowledges that, as may be agreed among the Company and one or more Purchasers, such Purchasers may not be required to fund their respective Subscription Amounts until such Purchasers receive evidence from the Company of the issuance of the Closing Shares on and as of the Closing Date in book-entry form registered in the name of the Purchaser (or its nominee as instructed by the Purchaser.

SECTION 3. Representations and Warranties of the Purchasers. Each Purchaser, severally and not jointly, represents and warrants to the Company that:

3.01 Validity. The execution, delivery and performance of this Agreement and the consummation by the Purchaser of the transactions contemplated hereby have been duly authorized by all necessary corporate, partnership, limited liability or similar actions, as applicable, on the part of such Purchaser. This Agreement has been duly executed and delivered by the Purchaser and, assuming that this Agreement constitutes the valid and binding obligation of the Company, constitutes a valid and binding obligation of the Purchaser, enforceable against it in accordance with its terms, except as limited by applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance, and any other laws of general application affecting enforcement of creditors’ rights generally, and as limited by laws relating to the availability of specific performance, injunctive relief, or other equitable remedies.

3.02 Brokers. There is no broker, investment banker, financial advisor, finder or other Person which has been retained by or is authorized to act on behalf of the Purchaser who is entitled to any fee or commission for which the Company will be liable in connection with the execution of this Agreement and the consummation of the transactions contemplated hereby.

3.03 Investment Representations and Warranties. The Purchaser understands and agrees that the offering and sale of the Securities has not been registered under the 1933 Act or any applicable state or other securities laws of the United States or any other jurisdiction and is being made in reliance upon federal and state exemptions for transactions not involving a public offering which depend upon, among other things, the bona fide nature of the investment intent and the accuracy of the Purchaser’s representations as expressed herein.

3.04 Acquisition for Own Account. The Purchaser is acquiring its entire beneficial ownership interest in the Securities for its own account or for an account over which it exercises sole discretion for another qualified institutional buyer or accredited investor for investment purposes and not with a view towards any distribution in a manner which would violate the 1933 Act or any applicable state or other securities laws of the United States or any other jurisdiction. The Purchaser has not been formed for the specific purpose of acquiring the Securities.

3.05 No General Solicitation. The Purchaser is not purchasing the Securities as a result of any advertisement, article, notice or other communication regarding the Securities published in any newspaper, magazine or similar media or broadcast over television, radio or the internet or presented at any seminar or any other general solicitation or general advertisement. The purchase of the Securities by the Purchaser has not been solicited by or through anyone other than the Company or, on the Company’s behalf, J.P. Morgan Securities LLC, BofA Securities, Inc., Piper Sandler & Co. and RBC Capital Markets, LLC (together, the “Placement Agents”), who have been engaged as joint placement agents for the offering of the Securities.

2

3.06 Ability to Protect Its Own Interests and Bear Economic Risks. The Purchaser is a sophisticated institutional investor, experienced in investing in private placement transactions and having such knowledge and experience in financial and business matters as to be capable of evaluating investment merits and risks independently, both in general and with regard to all transactions and investment strategies involving a security or securities, including its prospective investment in the Securities and participation in the transactions contemplated by this Agreement, and has the capacity to protect its own interests in connection with the transactions contemplated by this Agreement. The Purchaser has exercised independent judgment in evaluating their participation in the purchase of the Securities, and has determined based on their own independent review and such professional advice as they deem appropriate that their purchase of the Securities and participation in the transactions contemplated by this Agreement (i) are fully consistent with the Purchaser’s financial needs, objectives and condition, (ii) comply and are fully consistent with all investment policies, guidelines and other restrictions applicable to the Purchaser, (iii) do not and will not violate or constitute a default under the Purchaser’s charter, bylaws or other constituent document or under any law, rule, regulation, agreement or other obligation by which it is bound and (iv) is a fit, proper and suitable investment for the Purchaser, notwithstanding the substantial risks inherent in investing in or holding the Securities. The Purchaser is able to bear the substantial risks of an investment in the Securities including loss of the Purchaser’s entire investment therein.

3.07 Accredited Investor. The Purchaser is (i) a qualified purchaser (as defined in Section 2(a)(51)(A) of the Investment Company Act of 1940, as amended), (ii) a qualified institutional buyer (as defined in Rule 144A of the 1933 Act), or (iii) an “accredited investor” within the meaning of Rule 501(a) (1), (2), (3) or (7) under the 1933 Act, and satisfies any private placement requirements applicable in any non-U.S. jurisdiction where the Securities may be offered. Accordingly, the Purchaser understands that the offering meets the exemptions from filing under FINRA Rule 5123(b)(1)(C) or (J).. Such Purchaser is an institutional account as defined in FINRA Rule 4512(c). Accordingly, such Purchaser also understands that the offering meets (i) the exemptions from filing under FINRA Rule 5123(b)(1)(A) and (ii) the institutional customer exemption under FINRA Rule 2111(b).

3.08 Restricted Securities. The Purchaser understands that the Securities have not been registered under the securities laws of the United States or any other jurisdiction, are being offered for resale in transactions not requiring registration under the 1933 Act, and that the Securities will be characterized as “restricted securities” under the federal securities laws inasmuch as they are being acquired from the Company in a private placement under Section 4(a)(2) of the 1933 Act and that, under such laws and applicable regulations, unless the resale or transfer of such Securities is so registered, such Securities may not be resold or transferred in the United States or otherwise except in compliance with the registration requirements of the 1933 Act or any other applicable securities laws (or pursuant to any exemption therefrom or in a transaction not subject thereto).

3.09 Review and Advisors. The Purchaser has had the opportunity to review with the Purchaser’s tax advisors the U.S. federal, state, and local and non-U.S. tax consequences of its purchase of the Securities set forth opposite such Purchaser’s name on the Schedule of Purchasers and the transactions contemplated by this Agreement, and has made its own assessment and has satisfied itself concerning the relevant tax and other economic considerations relevant to its investment in the Securities. The Purchaser is relying solely on the Purchaser’s own determination as to tax consequences, and on the Purchaser’s own sources of information and advisors with respect to all tax matters, and not on any statements or representations of the Company, the Placement Agents or any of their respective agents. The Purchaser (and not the Company) shall be responsible for any of the Purchaser’s tax liability that may arise as a result of the transactions contemplated by this Agreement or ownership of the Securities. The Purchaser has conducted its own investigation of the Company and the Securities and has not relied on any statements or other information provided by the Placement Agents concerning the Company or the Securities or the offer and sale of the Securities, and has (i) received, reviewed and understood the offering materials as it deems necessary to make its decision to purchase the Securities, including financial and other information made available to it in connection with the Securities, the Company and the transactions contemplated by the Agreement, (ii) had the opportunity to ask questions of and receive answers from the Company directly, including and as it deems necessary to make its decision to purchase the Securities with respect to the financial information, the Securities, the Company and the transactions contemplated by the Agreement, and (iii) conducted and completed its own independent due diligence with respect to the Securities, the Company and the transactions contemplated by the Agreement. Based on

3

such information as the Purchaser deemed appropriate and without reliance upon the Placement Agents, the Purchaser has independently made its own analysis and decision to purchase the Securities. Except for the Frequency SEC Documents (as defined in the Merger Agreement), the information referenced in Section 3.11, the Company Presentation referenced in Section 4.16, information the Purchaser received in its capacity as a shareholder of the Company, and the representations, warranties and agreements of the Company expressly set forth in this Subscription Agreement, the Purchaser is relying on its own investment analysis and due diligence (including professional advice it deems appropriate) with respect to the transactions contemplated by this Agreement, the Securities and the business, condition (financial and otherwise), management, operations, properties and prospects of the Company and Frequency, including all business, legal, regulatory, accounting, credit and tax matters.

3.10 Residency. Such Purchaser’s residence (if an individual) or offices in which its investment decision with respect to the Securities was made (if an entity) are located at the address immediately below such Purchaser’s name on the Schedule of Purchasers, or as otherwise noted on the Schedule of Purchasers.

3.11 Disclosure of Information. The Purchaser has had an opportunity to review the Frequency SEC Documents and draft proposed risk factors contained in the data room, discuss the Company’s business, management, financial affairs and the terms and conditions of the offering of the Securities and the terms and related risks of the Merger with the Company’s management. The foregoing, however, does not limit or modify the representations and warranties of the Company in Section 4 of this Agreement or the right of the Purchasers to rely thereon.

SECTION 4. Representations and Warranties by the Company. The Company represents and warrants to the Purchasers that:

4.01 Absence of Changes. The Company has conducted its business only in the ordinary course of business (except for the execution and performance of this Agreement and the Merger Agreement, and the discussions, negotiations, and transactions related thereto) and (i) there has not been any change, condition, effect, event, circumstance, occurrence, result, state of facts or development (each, an “Effect”) that, singly or in the aggregate with any other Effect, has had or would reasonably be expected to have a materially adverse effect on (a) the business, condition (financial or otherwise), general affairs, management, assets, liabilities, operations, results of operations, earnings, prospects, properties, stockholders’ equity or financial performance of the Company and its subsidiary, taken together, or Frequency or (b) the ability or legal authority of the Company to perform its obligations under and to consummate the transactions contemplated by this Agreement and the Merger Agreement, including the issuance and sale of the Securities (a “Material Adverse Effect”), (ii) there have been no transactions entered into by the Company or any of its subsidiaries, other than those in the ordinary course of business and except as contemplated in this Agreement and the Merger Agreement, which are material with respect to the Company and its subsidiaries, considered as one enterprise, (iii) there has been no dividend or distribution of any kind declared, paid or made by the Company on any class of its capital stock, (iv) there has been no material adverse change to, and no material adverse development in, the business, condition (financial or otherwise), general affairs, management, assets, liabilities, operations, results of operations, earnings, prospects, properties, stockholders’ equity or financial performance of the Company and its subsidiaries considered as one enterprise, (v) there has been no satisfaction or discharge of any material lien, claim or encumbrance or payment of any obligation by the Company or any of its subsidiaries, except in the ordinary course of business, (vi) there has been no waiver, not in the ordinary course of business, by the Company or any of its subsidiaries of a material right or a material debt owed to it, (vii) neither the Company nor any of its subsidiaries has sold any material assets, singly or in the aggregate, outside of the ordinary course of business, (viii) neither the Company nor any of its subsidiaries has made any material change in or material amendment to, modification of or waiver of any material right under, or termination of any material contract, (ix) the Company has not experienced the loss of services of any executive officer (as defined in Rule 405 under the 1933 Act) and (x) there has not been any other event or condition that has had or would reasonably be expected to have a Material Adverse Effect. The Company has not taken any steps to seek protection pursuant to any bankruptcy law. The Company is not, as of the date hereof, and after giving effect to the transactions contemplated hereby to occur at Closing, will not be Insolvent (as defined below). For purposes of this Section 4.01, “Insolvent” means, with respect to any Person, (w) the present fair saleable value of such Person’s assets is less than the amount required to pay such Person’s total indebtedness, (x) such Person is unable to pay its debts and liabilities, subordinated, contingent or otherwise, as such debts and liabilities become absolute and matured, (y) such Person intends to incur or believes that it will incur debts that would be beyond its ability to pay as such debts mature or (z) such Person has unreasonably small capital with which to conduct the business in which it is engaged as such business is now conducted and is proposed to be conducted.

4

4.02 Organization and Good Standing of the Company. The Company is a corporation duly incorporated and is validly existing and in good standing under the laws of the State of Delaware, and has all necessary power and authority (i) to conduct its business in all material respects in the manner in which its business is currently being and is proposed to be conducted, (ii) to own or lease and use its property and assets in the manner in which its property and assets are currently owned or leased and used in all material respects and (iii) to perform its obligations under all contracts by which it is bound in all material respects. The Company is duly licensed and qualified as a foreign corporation to transact business and is in good standing in each jurisdiction in which such qualification is required, whether by ownership or leasing of property or the conduct of business, except where the failure so to qualify or to be in good standing would not have or reasonable be expected to have a Material Adverse Effect.

4.03 Subsidiaries. Except as set forth on Schedule 4.03, the Company does not have any subsidiaries and does not otherwise own any shares of capital stock or any interest in any other Person. The Company does not control directly or indirectly or have any direct or indirect equity participation or similar interest in any corporation, partnership, limited liability company, joint venture, trust or other business association or entity, except as set forth on Schedule 4.03.

4.04 Validity; Valid Issuance of Securities. The Company has all requisite corporate power and authority to enter into this Agreement and the Merger Agreement and to consummate the transactions contemplated by this Agreement and the Merger Agreement, subject only to the adoption of the Merger Agreement in accordance with the terms thereof by the Company’s stockholders under (i) the Delaware General Corporation Law and (ii) the Company’s certificate of incorporation. The execution and delivery of this Agreement and the consummation of the transactions contemplated by this Agreement by the Company have been duly authorized by all necessary corporate action on the part of the Company. Assuming the due authorization, execution and delivery by Purchaser of this Agreement and by Frequency and Merger Sub of the Merger Agreement, each of this Agreement and the Merger Agreement have been (or upon delivery will have been) duly executed and delivered by the Company and will constitute a legal, valid and binding obligation of the Company, enforceable against the Company in accordance with its terms, except as limited by applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance, and any other laws of general application affecting enforcement of creditors’ rights generally, and as limited by laws relating to the availability of specific performance, injunctive relief, or other equitable remedies. The Securities are duly authorized and, when issued, sold and delivered in accordance with the terms and for the consideration set forth in this Agreement, will be validly issued, fully paid and nonassessable and free and clear of any liens or other restrictions, other than restrictions on transfer under applicable state and federal securities laws or such restrictions as the Purchaser has agreed to in writing with the Company, and will not have been issued in violation of or subject to any preemptive or similar rights created under the Company’s certificate of incorporation or bylaws or the Delaware General Corporation Law.

4.05 Governmental Consents and Filings. Assuming the accuracy of the representations made by the Purchasers in Section 3 hereof and except as set forth in the Merger Agreement, no material consent, approval, order or authorization of, or registration, qualification, designation, declaration or filing with, or giving of notice to, any Governmental Entity (as defined below) is required on the part of the Company in connection with the execution and delivery of, or the consummation of the transactions contemplated by, this Agreement, except for filings pursuant to applicable state securities laws, which have been made or will be made in a timely manner. The Company is unaware of any facts or circumstances that might prevent the Company from obtaining or effecting any of the registrations, applications or filings described in this Section 4.05.

4.06 Absence of Violations, Defaults and Conflicts. Neither the Company nor any of its subsidiaries is (i) in violation of its charter, bylaws or similar organizational document, (ii) in default in the performance or observance of any obligation, agreement, covenant or condition contained in any contract, bond, debenture, indenture, mortgage, deed of trust, loan or credit agreement, note, lease or other agreement or instrument or evidence of indebtedness or any lease, license, franchise, permit, joint venture or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which it or any of them may be bound or to which any of the properties or assets of the Company or any subsidiary is subject (collectively, “Agreements and Instruments”), except for such defaults that would not, singly or in the aggregate, have or reasonably be expected to have a Material Adverse Effect, or (iii) in violation of any law, statute, rule, regulation, judgment, order, writ or decree of any

5

arbitrator, court, governmental body, regulatory body, administrative agency or other authority, body or agency having jurisdiction over the Company or any of its subsidiaries or any of their respective properties, assets or operations (each, a “Governmental Entity”), except for such violations that would not, singly or in the aggregate, have or reasonably be expected to have a Material Adverse Effect. The execution, delivery and the performance of this Agreement, the Registration Rights Agreement and the Merger Agreement and the consummation of the transactions contemplated herein and therein (including the issuance and sale of the Securities) and compliance by the Company with its obligations hereunder and thereunder do not and will not, whether with or without the giving of notice or passage of time or both, (1) conflict with or constitute a breach or violation of or default under, or result in the creation or imposition of any lien, charge or encumbrance upon any properties or assets of the Company or any subsidiary pursuant to, any of the Agreements and Instruments, (2) result in any violation of the provisions of the certificate of incorporation, bylaws or similar organizational document of the Company or any of its subsidiaries or (3) result in any violation of any applicable law, statute, rule, regulation, judgment, order, writ or decree of any Governmental Entity, except in the case of clauses (1) and (3), for such violations as would not, singly or in the aggregate, have or reasonably be expected to have a Material Adverse Effect, or materially affect the validity of the Securities or the legal authority of the Company to perform its obligations hereunder and timely comply with the terms of this Agreement or the Merger Agreement.

4.07 Absence of Proceedings. There is no action, suit, proceeding or, to the knowledge of the Company, inquiry or investigation, before or brought by any Governmental Entity now pending or, to the knowledge of the Company, threatened, against or affecting the Company, any of its subsidiaries or any Company director or officer, which would have or would reasonably be expected to have, singly or in the aggregate with all other such actions, suits, proceedings, inquiries or investigations, a Material Adverse Effect or which question or would, if determined or otherwise resolved adversely to the Company, reasonably be expected to materially affect the validity of the this Agreement, the Merger Agreement or the Securities or the legal authority of the Company to perform its obligations hereunder and under the Merger Agreement and timely comply in all material respects with the terms of this Agreement or the Merger Agreement. There are no material judgments, orders or decrees outstanding against the Company or any of its subsidiaries.

4.08 Possession of Licenses and Permits. The Company and its subsidiaries possess such permits, licenses, approvals, consents and other authorizations (collectively, “Governmental Licenses”) issued by the appropriate Governmental Entities necessary to conduct the business now operated by them, except where the failure so to possess would not, singly or in the aggregate, have or reasonably be expected to have a Material Adverse Effect. The Company and its subsidiaries are in compliance with the terms and conditions of all Governmental Licenses, except where the failure so to comply would not, singly or in the aggregate, have or reasonably be expected to have a Material Adverse Effect. All of the Governmental Licenses are valid and in full force and effect, except when the invalidity of such Governmental Licenses or the failure of such Governmental Licenses to be in full force and effect would not, singly or in the aggregate, have or reasonably be expected to have a Material Adverse Effect. Neither the Company nor any of its subsidiaries has received any notice of proceedings relating to the revocation or modification of any Governmental Licenses which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would have or would reasonably be expected to have a Material Adverse Effect.

4.09 Payment of Taxes. All United States federal income tax returns of the Company and its subsidiaries required by law to be filed have been filed, all such tax returns were correct and complete in all material respects and have been prepared in material compliance with all applicable law, and all taxes shown by such returns or otherwise assessed, which are due and payable, have been paid, except assessments against which appeals have been or will be taken and as to which adequate reserves have been provided and except, in each case, as would not have or reasonably be expected to have a Material Adverse Effect. No assessment in connection with United States federal income tax returns has been made against the Company. Subject to exceptions as would not be material, no claim has ever been made by a Governmental Entity in a jurisdiction where the Company does not file tax returns that the Company is subject to taxation by that jurisdiction. The Company and its subsidiaries have (i) filed all other tax returns that are required to have been filed by them through the date hereof or have timely requested extensions thereof pursuant to applicable state, local, or other foreign tax law, except insofar as the failure to file such tax returns would not reasonably be expected to have a Material Adverse Effect, and (ii) paid all taxes due pursuant to such filed tax returns, except for such taxes, if any, as are being contested in good faith and as to which adequate reserves have been established by the Company or its subsidiaries or where the failure to pay such taxes would not have or reasonably be expected to have a Material Adverse Effect. The unpaid taxes of the Company or any of its subsidiaries for periods

6

(or portions thereof) ending on or prior to the date of the most recent unaudited interim balance sheet do not materially exceed the accruals for current taxes set forth on such balance sheet, and since the date of such balance sheet, neither the Company nor any of its subsidiaries has incurred any material liability for taxes outside the ordinary course or business or otherwise inconsistent with past custom and practice. Each of the Company and Frequency is classified as a Subchapter C corporation for U.S. federal tax purposes.

4.10 Insurance. The Company and its subsidiaries carry or are entitled to the benefits of insurance, with recognized, financially sound and reputable insurers, in such amounts and with such deductibles and covering such risks as is adequate and customary for the conduct of their respective businesses and the value of their respective properties and assets, including policies covering real and personal property owned or leased by the Company against theft, damage, destruction, acts of vandalism and natural disasters and policies covering the Company for product liability claims and clinical trial liability claims, and all such insurance is in full force and effect. The Company has no reason to believe that it or any of its subsidiaries will not be able (i) to renew its existing insurance coverage as and when such policies expire or (ii) to obtain comparable coverage from similar institutions as may be necessary or appropriate to conduct its business as now conducted and at a cost that would not have or reasonably be expected to have a Material Adverse Effect. The Company has not been denied any insurance coverage that it has sought or for which it has applied.

4.11 Investment Company Act. The Company is not required, and upon the issuance and sale of the Securities or following completion of the Merger will not be required, to register as an “investment company” under the Investment Company Act of 1940, as amended.

4.12 Shell Company Status. Neither the Company nor Frequency is, or has ever been, an issuer identified in Rule 144(i)(1) promulgated under the 1933 Act.

4.13 Regulatory Matters. Except as would not, singly or in the aggregate, have or reasonably be expected to have a Material Adverse Effect: (i) neither the Company nor any of its subsidiaries has received any FDA Form 483, notice of adverse finding, warning letter or other correspondence or written notice from the U.S. Food and Drug Administration (“FDA”) or any other Governmental Entity alleging or asserting noncompliance with any Applicable Laws (as defined in clause (ii) below) or Authorizations (as defined in clause (iii) below); (ii) the Company and each of its subsidiaries is and has been in compliance with statutes, laws, ordinances, rules and regulations applicable to the Company and its subsidiaries for the ownership, testing, development, manufacture, packaging, processing, use, distribution, marketing, labeling, promotion, sale, offer for sale, storage, import, export or disposal of any product manufactured or distributed by the Company, including the Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 301, et seq., similar laws of other Governmental Entities and the regulations promulgated pursuant to such laws (collectively, “Applicable Laws”); (iii) the Company and each of its subsidiaries possesses all licenses, certificates, approvals, clearances, authorizations, permits and supplements or amendments thereto required by any such Applicable Laws or to carry on its businesses as now conducted (“Authorizations”) and such Authorizations are valid and in full force and effect and the Company is not in violation of any term of any such Authorizations; (iv) neither the Company nor any of its subsidiaries has received notice of any ongoing claim, action, suit, proceeding, hearing, enforcement, investigation, arbitration or other action from any Governmental Entity or third party alleging that any product, operation or activity is in violation of any Applicable Laws or Authorizations or has any knowledge that any such Governmental Entity or third party is considering any such claim, litigation, arbitration, action, suit, investigation or proceeding, nor, to the Company’s knowledge, has there been any noncompliance with or violation of any Applicable Laws by the Company or any of its subsidiaries that could reasonably be expected to require the issuance of any such communication or result in an investigation, corrective action, or enforcement action by FDA or similar Governmental Entity; (v) neither the Company nor any of its subsidiaries has received notice that any Governmental Entity has taken, is taking or intends to take action to limit, suspend, modify or revoke any Authorizations or has any knowledge that any such Governmental Entity is threatening or is considering such action; and (vi) the Company and each of its subsidiaries has filed, obtained, maintained or submitted all reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments as required by any Applicable Laws or Authorizations and that all such reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments were complete, correct and not misleading on the date filed (or were corrected or supplemented by a subsequent submission).

4.14 Compliance With Laws. The Company has complied in all material respects with, is not in material violation of, and has not received any written notice alleging any violation with respect to, any applicable provisions of any statute, law or regulation with respect to the conduct of its business, or the ownership or operation of its properties or assets.

7

4.15 Financial Statements; Controls; Books and Records. The Company has made available to each Purchaser its audited balance sheets as of December 31, 2022, together with related audited statements of operations, changes in stockholders’ equity and cash flows, and notes thereto, of the Company for the fiscal year ended December 31, 2022, and the unaudited balance sheets as of March 31, 2023, together with related unaudited statements of operations, changes in stockholders’ equity and cash flows, and notes thereto, of the Company for the three months ended March 31, 2023 (collectively, the “Financial Statements”). The Financial Statements have been prepared in accordance with United States generally accepted accounting principles (“GAAP”) applied on a consistent basis throughout the periods indicated, except that the Financial Statements may not contain all footnotes and other presentation items required by GAAP and are subject to normal and recurring year-end adjustments that are not reasonably expected to be material in amount. The Financial Statements fairly present in all material respects the financial condition and operating results of the Company as of the dates, and for the periods, indicated therein, subject to normal year-end adjustments. Except as set forth in the Financial Statements, between March 31, 2023 and the date of this Agreement, the Company has not incurred any material liabilities or obligations, contingent or otherwise, other than (i) liabilities incurred in the ordinary course of business; (ii) obligations under contracts and commitments incurred in the ordinary course of business; (iii) liabilities for transaction expenses incurred in connection with the transactions contemplated by this Agreement and the Merger Agreement; and (iv) liabilities and obligations of a type or nature not required under GAAP to be reflected in the Financial Statements. The Company maintains and will continue to maintain a standard system of accounting established and administered to provide reasonable assurance that transactions are recorded as necessary to permit preparation of the financial statements of the Company in conformity with GAAP. The Company has not extended or maintained credit, arranged for the extension of credit, modified or renewed an extension of credit, in the form of a personal loan or otherwise, to or for any director or executive officer of the Company. The minute books and other similar records of the Company contain complete and accurate records of all actions taken at any meetings of the Company’s stockholders, the Company’s Board of Directors or any committee thereof and of all written consents executed in lieu of the holding of any such meeting. The books and records of the Company have been maintained in accordance with good business and bookkeeping practices.

4.16 Information Provided. The Company Presentation dated June 2023 provided to the Purchasers in connection with the offering (the “Company Presentation”) does not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The information to be supplied by or on behalf of the Company for inclusion or incorporation by reference in the Registration Statement (as defined in the Merger Agreement), or supplied by or on behalf of the Company for inclusion in any filing pursuant to Rule 165 and Rule 425 under the 1933 Act or Rule 14a-12 under the 1934 Act (each a “Regulation M-A Filing”), shall not, at the time the Registration Statement or any such Regulation M-A Filing is filed with the Securities and Exchange Commission (the “Commission”), at any time it is amended or supplemented or at the time the Registration Statement is declared effective by the Commission, as applicable, contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein not misleading (or, in the case of the prospectus/proxy statement contained therein, not misleading in light of the circumstances under which it shall be made). The information to be supplied by or on behalf of the Company for inclusion in the Registration Statement to be sent to the stockholders of Frequency in connection with the meeting of Frequency’s stockholders (the “Public Company Meeting”), shall not, on the date the proxy statement/prospectus included in the Registration Statement is first mailed to stockholders of Frequency, at the time of the Public Company Meeting or at the Effective Time (as defined in the Merger Agreement), contain any statement that, at such time and in light of the circumstances under which it shall be made, is false or misleading with respect to any material fact, or omit to state any material fact necessary in order to make the statements made in the Registration Statement not false or misleading; or omit to state any material fact necessary to correct any statement in any earlier communication with respect to the solicitation of proxies for the Public Company Meeting that has become false or misleading.

4.17 No Additional Agreements. The Company does not have any agreement (including side letters) with any Purchaser with respect to (or any other Person acquiring securities in connection therewith) the transactions contemplated by this Agreement other than as specified in this Agreement. and, for the avoidance of doubt, does not have any agreement with any Purchaser on terms (economic or otherwise) more favorable to such Purchaser than as set forth in this Agreement.

8

4.18 Private Placement. None of the Company, its subsidiaries or any Person acting on its or their behalf, has, directly or indirectly, made any offers or sales of any security or solicited any offers to buy any security under any circumstances that would require registration under the 1933 Act of the Securities being sold pursuant to this Agreement. Assuming the accuracy of the representations and warranties of the Purchasers contained in Section 3 hereof, the issuance and sale of the Securities is exempt from registration under the 1933 Act

4.19 No General Solicitation. Neither the Company nor, to the Company’s knowledge, any Person acting on behalf of the Company has, directly or indirectly, offered or sold any of the Securities or Merger Shares or solicited any offers to buy any Securities or Merger Shares, under any circumstances that would require registration under the 1933 Act of the offer and sale of the Securities, including by any form of general solicitation or general advertising.

4.20 No Integrated Offering. Assuming the accuracy of the Purchasers’ representations and warranties set forth in Section 3 hereof, none of the Company, its subsidiaries nor, to the Company’s knowledge, any of its or their Affiliates or any Person acting on its or their behalf has, directly or indirectly, at any time within the past six (6) months, made any offers or sales of any Company or Frequency security or solicited any offers to buy any security under circumstances that would (i) eliminate the availability of the exemption from registration under Section 4(a)(2) of the 1933 Act in connection with the offer and sale by the Company of the Securities as contemplated hereby or (ii) cause the offering of the Securities pursuant to this Agreement to be integrated with prior offerings by the Company or Frequency for purposes of any applicable law, regulation or stockholder approval provisions, including under the rules and regulations of The Nasdaq Stock Market LLC (“Nasdaq”) and the Company, its subsidiaries and, to the Company’s knowledge, any of its or their Affiliates or any Person acting on its or their behalf will not, and the Company shall make commercially reasonable efforts to cause Frequency, any of its Affiliates or any Person acting on its or their behalf not to, directly or indirectly, take any action or steps that would require the registration of the issuance by the Company of the Securities under the 1933 Act.

4.21 Brokers. Other than the Placement Agents, there is no broker, investment banker, financial advisor, finder or other Person that has been retained by or is authorized to act on behalf of the Company that is entitled to any fee or commission in connection with the execution of this Agreement and the consummation of the transactions contemplated hereby. The Purchasers shall have no obligation with respect to any fees or with respect to any claims made by or on behalf of any broker, investment banker, financial advisor, finder or other Person that has been retained by or is authorized to act on behalf of the Company for fees of a type contemplated in this Section 4.21 that may be due in connection with the transactions contemplated by this Agreement.

4.22 Additional Representations and Warranties. The Company’s representations and warranties set forth in the Merger Agreement in Section 3.6 (Capitalization), 3.10 (Title to Assets), 3.11 (Real Property; Leasehold), 3.12 (Intellectual Property), 3.13 (Agreements, Contracts and Commitments), 3.17 (Employee and Labor Matters; Benefit Plans), 3.18 (Environmental Matters), 3.21 (Transactions with Affiliates) and 3.22 (Privacy and Data Security) are true and correct and are hereby incorporated by reference and made by the Company, as qualified by the disclosures in the Korro Disclosure Schedule (as defined in the Merger Agreement). To the knowledge of the Company, following customary due diligence, the representations and warranties of Frequency in the Merger Agreement and in any certificate or other writing delivered by Frequency pursuant thereto are true and correct and are hereby incorporated by reference and made by the Company to the Purchasers, as qualified by the disclosures in the Frequency Disclosure Schedule (as defined in the Merger Agreement).

4.23 Reliance by Purchasers. The Company acknowledges that each Purchaser will rely upon the truth and accuracy of, and the Company’s compliance with, the representations, warranties, agreements, acknowledgements and understandings of the Company set forth in this Agreement and the Merger Agreement.

4.24 No Price Stabilization or Manipulation; Compliance with Regulation M. Neither the Company nor Frequency has taken, directly or indirectly, any action designed to or that might cause or result in stabilization or manipulation of the price of any security of the Company or Frequency to facilitate the sale or resale of the Securities or Merger Shares or otherwise, and has taken no action that would directly or indirectly violate Regulation M under the 1934 Act.

9

SECTION 5. Covenants.

5.01 Further Assurances. At or prior to Closing, the Company and each Purchaser (severally and not jointly with any other Purchaser) agrees to cooperate and generally do such reasonable acts and things in good faith as may be necessary to timely satisfy each of the conditions to be satisfied by it as provided in Section 6 of this Agreement, effectuate the intents and purposes of this Agreement subject to the terms and conditions hereof and evidence the fulfillment of the agreements herein contained.

5.02 Disclosure of Transactions and Other Material Information. The Company shall or shall cause Frequency to, on or before 9:00 a.m., New York City time, on the Business Day immediately following the Effective Date (or if this Agreement is executed between midnight and 9:00 a.m., New York City time, on any Business Day, no later than 9:01 a m. on the date the Agreement is executed) (the “Disclosure Deadline”), issue one or more press releases (the “Press Release”) and file with the Commission a Current Report on Form 8-K (collectively with the Press Release, the “Disclosure Document”), which Current Report on Form 8-K shall include as exhibits this Agreement, the Merger Agreement, the Company Presentation and the Press Release, disclosing any material nonpublic information within the meaning of the federal securities laws that the Company, Frequency or their respective officers, directors, employees, agents or any other Person, including the Placement Agents, acting at their direction or on their behalf has provided to the Purchasers in connection with the transactions contemplated by this Agreement or the Merger Agreement prior to the filing of the Disclosure Document (which includes, for the avoidance of doubt, the material terms of the transactions contemplated hereby, the material terms of the Merger Agreement and the transactions contemplated thereby and any other material non-public information made available in the data room). The Company represents and warrants that, from and after the issuance of the Disclosure Document, no Purchaser shall be in possession of any material nonpublic information received from the Company, Frequency or their respective officers, directors, employees, agents, or any other Person, including the Placement Agents, acting at their direction or on their behalf. From and after the issuance of the Disclosure Document, neither the Company, Frequency, nor their respective officers, directors, employees, agents or any other Person, including the Placement Agents, acting at their direction or on their behalf shall provide any material, nonpublic information to any Purchaser, unless otherwise specifically agreed in writing by such Purchaser, except in the case of material, nonpublic information provided to an observer of the Company’s or Frequency’s board of directors or member of the Company’s or Frequency’s board of directors who is affiliated with such Purchaser or in a Final Waiver Notice to Informed Purchasers (as such terms are defined below) in accordance with Section 5.05 hereof. The Company shall not, and shall cause Frequency and its and their respective officers, directors, employees, agents and any other Person, including the Placement Agents, acting at their direction or on their behalf not to, publicly disclose the name of any Purchaser or any affiliate or investment advisor of any Purchaser, or include the name of any Purchaser or any affiliate or investment advisor of any Purchaser without the prior written consent (including by e-mail) of such Purchaser (i) in any press release or marketing materials, or (ii) in any filing with the Commission or any regulatory agency or trading market, except (A) as required by the federal securities laws, rules or regulations, (B) to the extent such disclosure is required by other laws, rules or regulations, at the request of the staff of the Commission or regulatory agency or under regulations of any national securities exchange on which Frequency’s securities are listed for trading or (C) to the extent such disclosure contains only information previously approved in accordance with this Section 5.02, and in the case of any disclosure made pursuant to clause (ii), the Company will provide the Purchaser with prior written notice (including by e-mail) of the applicable portion of such filing. Upon the earlier of (i) the Disclosure Deadline, (ii) the issuance of the Press Release and (iii) the filing of the Disclosure Document, each Purchaser shall no longer be subject to any confidentiality or similar obligations under any current agreement, whether written or oral, with the Company, Frequency or their respective officers, directors, Affiliates, employees or agents, or any other Person, including the Placement Agents, acting at their direction or on their behalf, in each case entered into in connection with the sale of the securities hereunder and the Merger. The Company understands and confirms that the Purchasers and their respective Affiliates will rely on the foregoing representations in effecting transactions in securities of the Company.

5.03 Expenses. The Company and each Purchaser is liable for, and will pay, its own expenses incurred in connection with the negotiation, preparation, execution and delivery of this Agreement, including attorneys’ and consultants’ fees and expenses; provided that, at the Closing, the Company shall reimburse Citadel CEMF Investments Ltd. for the documented reasonable legal fees, expenses and disbursements incurred by it, any of its Affiliates or its investment advisor in connection with the negotiation, preparation, execution and delivery of this Agreement and the transactions contemplated hereby. Notwithstanding the foregoing, the Company shall pay all transfer agent fees, stamp taxes and other taxes and duties levied in connection with the issuance, sale and delivery of the Securities to the Purchasers.

10

5.04 Blue Sky Laws. The Company, on or before the Closing Date, shall take such action as the Company shall reasonably determine is necessary in order to obtain an exemption for or to qualify the Securities for sale to each Purchaser at the Closing pursuant to this Agreement under applicable securities or “blue sky” laws of the states of the United States (or to obtain an exemption from such qualification). The Company shall make all filings and reports relating to the offer and sale of the Securities required under applicable securities or “blue sky” laws of the states of the United States following the Closing Date. The Company shall provide evidence of such actions promptly upon the written request of any Purchaser.

5.05 No Amendment or Waiver of Merger Agreement Terms. The Company shall not amend, modify or waive (or approve an amendment, modification or a waiver requested by Frequency of, or fail to contest an action regarding a breach of) any provision of the Merger Agreement in a manner that would reasonably be expected to be adverse to the Purchasers without the consent of the Purchaser Majority (the “Purchaser Consent”). Prior to seeking such consent from the Purchasers, the Company shall provide written notice to the Purchasers that such consent is being sought (the “Initial Waiver Notice”). Such Initial Waiver Notice shall identify the nature of the change sought (e.g., whether it is requesting an amendment or modification to or a waiver under the Merger Agreement and the party seeking the amendment, modification or waiver), but shall not disclose any material, nonpublic information pertaining to the Company, Frequency or their respective operations. After the Initial Waiver Notice is received, each Purchaser shall have five Business Days to elect to receive a full request for Purchaser Consent (the “Final Waiver Notice”), such Final Waiver Notice containing the substance of the amendment, modification or waiver being requested and any other relevant information. If a Purchaser elects or receive a Final Waiver Notice, the Final Waiver Notice shall be sent to such consenting Purchaser (an “Informed Purchaser”) and the approval of both (a) the Informed Purchasers who have committed, in the aggregate, to purchase at least a majority of the Securities that all Informed Purchasers have agreed, in the aggregate, to purchase and (b) any Informed Purchaser who has committed to purchase at least $14,900,000 of the Securities shall be required to approve the requested amendment, modification or waiver. If no Purchaser has elected to receive the Final Waiver Notice within five Business Days following delivery of the Initial Waiver Notice, then no consent shall be required under this Section 5.05. If a Final Waiver Notice contains material, nonpublic information, the Company shall cause Frequency to, on or before 9:00 a.m., New York City time, on the Business Day immediately following the execution of such amendment, modification or waiver, file with the Commission a Current Report on Form 8-K, which shall include as an exhibit the amendment, modification or waiver, disclosing any material, nonpublic information within the meaning of the federal securities laws that was contained in such Final Waiver Notice.

5.06 Equal Treatment of Purchasers. No consideration shall be offered or paid to any Purchaser to amend or consent to a waiver or modification of any provision of this Agreement unless the same consideration is also offered to all of the Purchasers. For clarification purposes, this provision constitutes a separate right granted to each Purchaser by the Company and negotiated separately by each Purchaser and shall not in any way be construed as the Purchasers acting in concert or as a group with respect to the purchase, disposition or voting of shares of Common Stock or otherwise.

5.07 Integration. The Company shall not, and shall use its commercially reasonable efforts to ensure that neither Frequency nor any Affiliate of the Company shall, sell, offer for sale or solicit offers to buy or otherwise negotiate in respect of any security (as defined in Section 2 of the 1933 Act) that will be integrated with the offer or sale of the Securities in a manner that would require the registration under the 1933 Act of the offer or sale of the Securities to the Purchasers, or that would be integrated with the offer or sale of the Securities for purposes of the rules and regulations of any National Exchange or other trading market such that it would require stockholder approval prior to the Closing; provided, however, that this Section 5.07 shall not limit the Company’s or Frequency’s right to issue shares of capital stock pursuant to the Merger Agreement.

5.08 Shareholder Rights Plan. The Company shall not make or enforce, shall cause Frequency not to make or enforce, and shall not consent to any other Person making or enforcing any claim that any Purchaser is an “Acquiring Person” under any control share acquisition, business combination, poison pill (including any distribution under a rights agreement) or similar anti-takeover plan or arrangement or law (including Section 203 of the Delaware General Corporation Law) in effect or hereafter adopted by Frequency, or that any Purchaser could be deemed to trigger the provisions of any such plan or arrangement, in either case solely by virtue of receiving Securities or Merger Shares under this Agreement or the Merger Agreement, as applicable; provided, however, that no such Purchaser owns any equity in Frequency prior to its purchase of the Securities hereunder.

11

5.09 Principal National Exchange Listing. In the time and manner required by Frequency’s principal National Exchange, the Company shall cause Frequency to prepare and file with such National Exchange an additional shares listing application covering all of the Merger Shares and shall use its commercially reasonable efforts to take all steps necessary to cause all of the Merger Shares to be approved for listing on such National Exchange as promptly as possible thereafter.

5.10 Lock-Up Agreements. The Company shall not consent or agree to amend, alter, waive or otherwise modify the terms of any of the Korro Lock-Up Agreements (as defined in the Merger Agreement) without the consent of the Purchaser Majority.

5.11 Listing; Reverse Split. At or prior to the Effective Time (as defined in the Merger Agreement), the Company shall use commercially reasonable efforts to cause Frequency to (a) prepare and timely submit to Nasdaq a notification form of the Nasdaq Reverse Split and submit a copy of the amendment to Frequency’s certificate of incorporation to effect the Nasdaq Reverse Split to Nasdaq on or before the Closing Date and (b) submit to its stockholders at the Frequency Stockholder Meeting the Reverse Stock Split Proposal (each as defined in the Merger Agreement) and take such other actions as shall be necessary to effectuate the Nasdaq Reverse Split. Following the Closing, the Company shall, and shall cause Frequency to, take all other actions necessary to maintain compliance with Nasdaq listing standards.

SECTION 6. Conditions of Closing.

6.01 Conditions of the Purchasers’ Obligations at the Closing. The obligations of each Purchaser under Section 2 hereof are subject to the fulfillment, at or prior to the Closing, of all of the following conditions, unless otherwise waived by such Purchaser solely as to itself.

(a) Representations and Warranties. Each of the representations and warranties of the Company shall be true and correct in all respects on the Effective Date, and shall be true and correct in all material respects on and as of the Closing Date with the same force and effect as though such representations and warranties had been made on and as of the Closing Date (except (i) representations and warranties that are qualified by materiality or Material Adverse Effect, which shall be true and correct in all respects and (ii) to the extent expressly made as of a particular date, in which case such representations and warranties shall be true and correct as of such date).

(b) Performance. The Company shall have performed and complied in all material respects with all covenants, agreements, obligations and conditions contained in this Agreement that are required to be performed or complied with by it on or prior to the Closing Date.

(c) Compliance Certificate. The Chief Executive Officer of the Company shall have delivered to the Purchasers at the Closing Date a certificate, in form and substance reasonably acceptable to the Purchasers, certifying that the conditions specified in Sections 6.01(a), 6.01(b), 6.01(d), 6.01(f), 6.01(g), 6.01(j), 6.01(k), 6.01(l) and 6.01(m) of this Agreement have been fulfilled.

(d) Qualification under Securities Laws; Consents. All registrations, qualifications, permits and approvals, if any, required under applicable securities laws shall have been obtained for the lawful execution, delivery and performance of this Agreement. The Company shall have obtained in a timely fashion any and all other consents, permits, approvals, registrations and waivers necessary for consummation of the purchase and sale of the Securities and issuance of the Merger Shares (including the waiver of any applicable registration rights that could affect the rights of the Purchasers under this Agreement), all of which shall be and remain so long as necessary in full force and effect.

(e) Secretary’s Certificate. The Secretary of the Company shall have delivered to the Purchasers at the Closing a certificate, in the form of Exhibit C, certifying (i) the certificate of incorporation and bylaws of the Company, (ii) authorization of the Board of Directors of the Company approving this Agreement and the transactions contemplated under this Agreement (including the Merger Agreement) and (iii) as to certificates evidencing the good standing of the Company in Delaware issued by the Secretary of State of Delaware and in the Commonwealth of Massachusetts issued by the Secretary of the Commonwealth of Massachusetts, each as of a date within five Business Days of the Closing Date.

12

(f) Merger. All conditions to the closing of the Merger shall have been satisfied or waived (other than the Closing hereunder and other than those conditions which, by their nature, are to be satisfied at the closing of the transactions contemplated by the Merger Agreement, but subject to the satisfaction or waiver of such conditions as of the consummation of the Merger), and the closing of the Merger shall be set to occur immediately after the Closing hereunder. No amendment, modification or waiver of any provision of the Merger Agreement shall have been made that would reasonably be expected to be adverse to Purchasers without the consent of the Purchaser Majority.

(g) No Injunction. No statute, rule, regulation, executive order, decree, ruling or injunction shall have been enacted, entered, promulgated or endorsed by any Governmental Entity that prohibits the consummation of any of the transactions contemplated by this Agreement or the Merger Agreement.

(h) Registration Rights Agreement. The Company shall have delivered the fully executed Registration Rights Agreement and such agreement shall be in full force and effect.

(i) Opinion of Company Counsel. The Purchasers shall have received from Goodwin Procter LLP, counsel for the Company, an opinion, dated as of the Closing, in substantially the form of Exhibit B hereto.

(j) Registration Statement; Proxy Statement/Prospectus. The Registration Statement shall have become effective under the 1933 Act, and shall not be subject to any stop order or proceeding seeking a stop order with respect to the Registration Statement that has not been withdrawn, and no similar proceeding shall have been initiated or, to the knowledge of the Company, threatened by the Commission or its staff.

(k) Nasdaq. Frequency shall have received approval from Nasdaq that the shares of Frequency Common Stock (as defined in the Merger Agreement) to be issued in the Contemplated Transactions (as defined in the Merger Agreement) shall have been approved for listing (subject to official notice of issuance) on Nasdaq. The Nasdaq Reverse Split shall have been effectuated.

(l) Financing Amount. Assuming and after giving effect to funding of the Subscription Amount of the Purchaser asserting this closing condition, the Company shall receive at Closing gross proceeds of at least the Financing Amount.

(m) No Material Adverse Effect. Since the Effective Date, no Material Adverse Effect or, to the Company’s knowledge, following customary due diligence, Frequency Material Adverse Effect (as such term is defined in the Merger Agreement as in effect as of the date hereof) shall have occurred.

6.02 Conditions of the Company’s Obligations. The obligations of the Company under Section 2 hereof are subject to the fulfillment, at or prior to the Closing, of all of the following conditions, any of which may be waived in whole or in part by the Company in its absolute discretion.

(a) Representations and Warranties. The representations and warranties of the Purchasers contained in this Agreement shall be true and correct in all material respects as of the Effective Date and true and correct in all material respects on and as of the Closing Date with the same effect as though such representations and warranties had been made on and as of the Closing Date (except to the extent expressly made as of an earlier date in which case such representations and warranties shall be true and correct in all material respects as of such earlier date).

(b) Performance. Each Purchaser shall have performed and complied with all covenants, agreements, obligations and conditions contained in this Agreement that are required to be performed or complied with by it on or prior to the Closing Date.

13

(c) Qualification under Securities Laws. All registrations, qualifications, permits and approvals, if any, required under applicable securities laws shall have been obtained for the lawful execution, delivery and performance of this Agreement.

(d) Merger. All conditions to the closing of the Merger shall have been satisfied or waived (other than the Closing hereunder and other than those conditions which, by their nature, are to be satisfied at the closing of the transactions contemplated by the Merger Agreement, but subject to the satisfaction or waiver of such conditions as of the consummation of the Merger), and the closing of the Merger shall be set to occur immediately after the Closing hereunder.

SECTION 7. Transfer Restrictions; Restrictive Legend.

7.01 Transfer Restrictions. Each Purchaser understands that the Company may, as a condition to the transfer of any of the Securities or Merger Shares, require that the request for transfer be accompanied by a customary certificate to of counsel reasonably satisfactory to the Company, to the effect that the proposed transfer does not result in a violation of the 1933 Act, unless such transfer is covered by an effective registration statement or is exempt from the registration requirements of the 1933 Act, including under Rule 144. It is understood that the certificates or book entries evidencing the Securities or Merger Shares may bear substantially the following legend:

“THE OFFER AND SALE OF THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE SECURITIES LAWS. THEY MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF A REGISTRATION STATEMENT IN EFFECT WITH RESPECT TO THE SECURITIES UNDER SUCH ACT OR APPLICABLE STATE SECURITIES LAWS OR A VALID EXEMPTION FROM REGISTRATION UNDER SUCH ACT OR APPLICABLE STATE SECURITIES LAWS.”

SECTION 8. Definitions. Unless the context otherwise requires, the terms defined in this Section 8 shall have the meanings specified for all purposes of this Agreement.

“1933 Act” means the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder.

“1934 Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

“Affiliate” shall have the meaning ascribed to such term in Rule 12b-2 of the General Rules and Regulations under the 1934 Act.

“Business Day” means any day except (a) a Saturday or Sunday or (b) any day on which banks in the City of New York are authorized or required by law or executive order to be closed; provided, however, that Lincoln’s Birthday (February 12) and Election Day shall not be excluded from the definition of Business Day by virtue of this clause (b).

“Financing Amount” means $100,000,000.

“Nasdaq Reverse Split” means a reverse stock split of all outstanding shares of Frequency Common Stock at a reverse stock split ratio as mutually agreed to by Frequency and Korro that is effected by Frequency for the purpose of maintaining compliance with Nasdaq listing standards.”

“National Exchange” means the Nasdaq Global Select Market, the Nasdaq Global Market, the Nasdaq Capital Market, or the New York Stock Exchange.

“Person” means an individual or corporation, partnership, trust, incorporated or unincorporated association, joint venture, limited liability company, joint stock company, government (or an agency or subdivision thereof) or other entity of any kind.

“Purchase Price” means an amount equal to (i) the Korro Equity Value (as defined in the Merger Agreement), (ii) divided by the number of outstanding shares of Korro Common Stock (as defined in the Merger Agreement but excluding the Securities being issued hereunder) as of immediately prior to the closing of offering of the Securities hereunder.

14

“Purchaser Majority” means, prior to the Closing, the Purchasers committed to purchase at least a majority the Securities, provided that each Purchaser (together with its affiliated funds) who has committed to purchase at least $14,900,000 of the Securities is included in such majority and, following the Closing, both (i) the Purchasers who hold at least a majority of the Securities (including any Frequency Common Stock issued in exchange therefore) still held by the Purchasers, and (ii) each Purchaser (together with its affiliated funds) (A) whose Subscription Amount exceeds $14,900,000 and (B) who continues to hold at least fifty percent (50%) of the Securities (including any Frequency Common Stock issued in exchange therefore) purchased on the Closing Date.

“Registration Rights Agreement” means the Registration Rights Agreement, in the form attached hereto as Exhibit A, to be entered into at the Closing among the Company and each Purchaser.

“Rule 144” means Rule 144 promulgated by the Commission pursuant to the 1933 Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same effect as Rule 144.

SECTION 9. Miscellaneous.

9.01 Waivers and Amendments. Neither this Agreement, nor any provision hereof, may be changed, waived, amended or modified orally or by course of dealing, but only by an instrument in writing executed by the Company and the Purchaser Majority, provided that, (a) if any, change, waiver, amendment, modification disproportionately and adversely impacts a Purchaser (or a subset of Purchasers), the consent of such disproportionately impacted Purchaser (or each Purchaser within such subset of Purchasers) shall be required and (b) the consent of each Purchaser shall be required for any change in the Purchase Price or applicable Purchaser’s Subscription Amount, any change in the type of security to be issued to Purchasers at Closing, or the amendment, modification or waiver of this Section 9.01, of Section 9.13 or of any of the closing conditions set forth in Sections 6.01(a), 6.01(j) 6.01(k) or 6.01(l). No waiver of any default with respect to any provision, condition or requirement of this Agreement shall be deemed to be a continuing waiver in the future or a waiver of any subsequent default or a waiver of any other provision, condition or requirement hereof, nor shall any delay or omission of any party to exercise any right hereunder in any manner impair the exercise of any such right.

9.02 Notices. All notices, requests, consents, and other communications under this Agreement shall be in writing and shall be deemed delivered (a) when delivered, if delivered personally, (b) four Business Days after being sent by registered or certified mail, return receipt requested, postage prepaid, (c) one Business Day after being sent via a reputable nationwide overnight courier service guaranteeing next Business Day delivery, (d) on the date of transmission, if such notice or communication is delivered via electronic mail at the e-mail address specified in this Section 9.02 prior to 5:00 P.M., New York City time, on a Business Date or (e) the next Business Day after the date of transmission, if such notice or communication is delivered by electronic mail at the e-mail address specified in this Section 9.02 on a day that is not a Business Day or after 5:00 P.M., New York City time, on any Business Day, in each case to the intended recipient as set forth below, with respect to the Company, and to the addresses set forth on the Schedule of Purchasers with respect to the Purchasers; provided, in the cases of clauses (d) and (e), that notice shall not be deemed given or effective if the sender receives an automatic system-generated response that such electronic mail was undeliverable. The addresses for such notices and communications shall be as follows:

if to the Company:

Korro Bio, Inc.

One Kendall Square, Building 600-700

Suite 6-401

Cambridge, MA 02139

Attention:     Vineet Agarwal, Chief Financial Officer

          Shelby Walker, General Counsel

Email:           vagarwal@korrobio.com

          swalker@korrobio.com

15

with a copy to (which shall not constitute notice):

Goodwin Procter LLP

100 Northern Avenue

Boston, MA 02210

Attention: Kingsley Taft, Marianne Sarrazin

Email: KTaft@goodwinlaw.com, MSarrazin@goodwinlaw.com

or at such other address as the Company or each Purchaser may specify by written notice to the other parties hereto in accordance with this Section 9.02.

9.03 Cumulative Remedies; Specific Performance. None of the rights, powers or remedies conferred upon each Purchaser, on the one hand, or the Company, on the other hand, shall be mutually exclusive, and each such right, power or remedy shall be cumulative and in addition to every other right, power or remedy, whether conferred by this Agreement or now or hereafter available at law, in equity, by statute or otherwise. Each of the Purchasers and the Company acknowledges and agrees that, in view of the uniqueness of the securities referenced herein and the transactions contemplated hereby and by the Merger Agreement, money damages will not provide an adequate remedy at law if this Agreement or the Merger Agreement are not performed in accordance with their terms, and therefore agrees that, in addition to being entitled to exercise all rights provided hereunder or granted by law, including recovery of damages (money or otherwise), each of the Purchasers and the Company shall be entitled to specific performance under this Agreement, without the requirement of either proving the inadequacy of monetary damages as a remedy (or irreparable harm) or the posting of a bond. The parties hereby agree to waive in any action for specific performance of any obligation the defense that a remedy at law would be inadequate.

9.04 Successors and Assigns. All the terms and provisions of this Agreement shall be binding upon and inure to the benefit of and be enforceable by the respective parties hereto, the successors and permitted assigns of each Purchaser and the successors of the Company, whether so expressed or not. None of the Purchasers may assign its rights or obligations hereunder without the prior written consent of the Company, except that a Purchaser may, without the prior consent of the Company, assign its rights to purchase the Securities hereunder to any of its affiliates or to any other investment funds or accounts managed or advised by the investment manager who acts on behalf of such Purchaser (provided each such assignee agrees to be bound by the terms of this Agreement and makes the same representations and warranties set forth in Section 3 hereof). The Company may not assign its rights or obligations hereunder without the consent of the Purchaser Majority. This Agreement shall not inure to the benefit of or be enforceable by any other Person except as expressly set forth herein.

9.05 Exculpation of Placement Agents. Each Purchaser, individually and not jointly, represents and warrants and agrees for the express benefit of each of the Placement Agents, its affiliates and its representatives that:

(a) Each of the Placement Agents is acting solely as a placement agent to the Company in connection with the sale of the Securities and is not acting as an underwriter in any other capacity and is not and shall not be construed as a financial advisor or as a fiduciary for the Purchaser, the Company, or any other Person or entity in connection with the issue and purchase of the Securities or the transactions contemplated by this Agreement.

(b) No Placement Agent or any of their respective directors, officers, employees, representative, controlling persons and affiliates (i) shall be liable for any improper payment made in accordance with the information provided by the Company, (ii) has prepared any disclosure or offering document in connection with the offer and sale of the Securities by the Placement Agents or their respective affiliates, (iii) has made or will make any representation or warranty, express or implied, of any kind or character, and has not provided any advice or recommendation to the Purchasers in connection with the transactions contemplated by this Agreement, (iv) shall have responsibility with respect to the accuracy, completeness or adequacy of any information that’s publicly available or supplied to them by the Company, (v) has any responsibilities with respect to any representations, warranties or agreements made by any Person under or in connection with the transactions contemplated by the Agreement or any of the documents furnished pursuant thereto or in connection therewith, or the execution, accuracy, completeness, value, genuineness, legality, validity or enforceability (with respect to any Person) or any thereof, as of any date, of any information, certificates or documentation delivered by or on behalf of the Company pursuant to this Agreement,

16

the Registration Rights Agreement or the Merger Agreement, or in connection with any of the transactions contemplated by such agreements, including any valuation, offering or marketing materials, or any omissions from such materials; or (vi) shall be liable for the business, affairs, financial condition, operations, properties or prospects of, or any other matter concerning the Company, Frequency, the Merger or the transactions contemplated by this Agreement.

(c) The Placement Agents, their respective affiliates and their respective representatives shall be entitled to rely on, and shall be protected in acting upon, any certificate, instrument, opinion, notice, letter or any other document or security delivered to any of them by or on behalf of the Company.

9.06 Headings. The headings of the Sections and paragraphs of this Agreement have been inserted for convenience of reference only and do not constitute a part of this Agreement.

9.07 Governing Law; Jurisdiction. This Agreement shall be governed by, and construed in accordance with, the laws of the State of Delaware, regardless of the laws that might otherwise govern under applicable principles of conflicts of laws. IN ANY ACTION OR PROCEEDING BETWEEN ANY OF THE PARTIES ARISING OUT OF OR RELATING TO THIS AGREEMENT OR ANY OF THE CONTEMPLATED TRANSACTIONS, EACH OF THE PARTIES: (A) IRREVOCABLY AND UNCONDITIONALLY CONSENTS AND SUBMITS TO THE EXCLUSIVE JURISDICTION AND VENUE OF THE COURT OF CHANCERY OF THE STATE OF DELAWARE OR, TO THE EXTENT SUCH COURT DOES NOT HAVE SUBJECT MATTER JURISDICTION, THE SUPERIOR COURT OF THE STATE OF DELAWARE OR THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF DELAWARE, (B) AGREES THAT ALL CLAIMS IN RESPECT OF SUCH ACTION OR PROCEEDING SHALL BE HEARD AND DETERMINED EXCLUSIVELY IN ACCORDANCE WITH CLAUSE (A) OF THIS SECTION 9.07, (C) WAIVES ANY OBJECTION TO LAYING VENUE IN ANY SUCH ACTION OR PROCEEDING IN SUCH COURTS, (D) WAIVES ANY OBJECTION THAT SUCH COURTS ARE AN INCONVENIENT FORUM OR DO NOT HAVE JURISDICTION OVER ANY PARTY, (E) AGREES THAT SERVICE OF PROCESS UPON SUCH PARTY IN ANY SUCH ACTION OR PROCEEDING SHALL BE EFFECTIVE IF NOTICE IS GIVEN IN ACCORDANCE WITH SECTION 9.02 OF THIS AGREEMENT AND (F) IRREVOCABLY WAIVES THE RIGHT TO TRIAL BY JURY.

9.08 Survival. The representations and warranties of the Company and the Purchasers contained in Sections 3 and 4 and the agreements and covenants set forth in Sections 5 and 9 shall survive the Closing for the applicable statute of limitations (unless such covenant or agreement terminates earlier in accordance with its terms), which shall not be extended by Section 8106(c) of Title 10 of the Delaware Code or any similar law. Each Purchaser shall be responsible only for its own representations, warranties, agreements and covenants hereunder.

9.09 Counterparts; Effectiveness. This Agreement may be executed in any number of counterparts and by different parties hereto in separate counterparts, with the same effect as if all parties had signed the same document. All such counterparts (including counterparts delivered by facsimile or other electronic format) shall be deemed an original, shall be construed together and shall constitute one and the same instrument. This Agreement shall become effective when each party hereto shall have received counterparts hereof signed by all of the other parties hereto.

9.10 Entire Agreement. This Agreement and the Registration Rights Agreement contain the entire agreement among the parties hereto with respect to the subject matter hereof and, except as set forth below, this agreement supersedes and replaces all other prior agreements, written or oral, among the parties hereto with respect to the subject matter hereof. Notwithstanding the foregoing or anything to the contrary in this Agreement, and subject to Section 5.02, this Agreement shall not supersede any confidentiality or other non-disclosure agreements that may be in place between the Company and any Purchaser as of the date hereof.

9.11 Severability. If any provision of this Agreement shall be found by any court of competent jurisdiction to be invalid or unenforceable, the parties hereby waive such provision to the extent that it is found to be invalid or unenforceable. Such provision shall, to the maximum extent allowable by law, be modified by such court so that it becomes enforceable, and, as modified, shall be enforced as any other provision hereof, all the other provisions hereof continuing in full force and effect.

17

9.12 Independent Nature of Purchasers’ Obligations and Rights. The obligations of each Purchaser under this Agreement are several and not joint with the obligations of any other Purchaser, and no Purchaser shall be responsible in any way for the performance or non-performance of the obligations of any other Purchaser under this Agreement. The decision of each Purchaser to Purchase securities pursuant to this Agreement has been made by such Purchaser independently of any other Purchaser and independently of any information, material, statements or opinions as to the business, affairs, operations, assets, properties, liabilities, results of operations, condition (financial or otherwise) or prospects of the Company that may have been made or given by any other Purchaser or by any agent or employee of any other Purchaser, and no Purchaser or any of its agents or employees shall have any liability to any other Purchaser (or any other Person) relating to or arising from any such information, materials, statements or opinions. Each Purchaser acknowledges that no other Purchaser has acted as agent for such Purchaser in connection with making its investment hereunder and that no Purchaser will be acting as agent of such Purchaser in connection with monitoring its investment in the Securities or enforcing its rights under this Agreement. Nothing contained herein, and no action taken by any Purchaser pursuant hereto, shall be deemed to constitute the Purchasers as, and the Company acknowledges that the Purchasers do not so constitute, a partnership, an association, a joint venture or any other kind of entity, or create a presumption that the Purchasers are in any way acting in concert or as a group (including a “group” within the meaning of Section 13(d)(3) of the 1934 Act), and the Company will not assert any such claim with respect to such obligations or the transactions contemplated by this Agreement, and the Company acknowledges that the Purchasers are not acting in concert or as a group with respect to such obligations or the transactions contemplated by this Agreement. The Company acknowledges and each Purchaser confirms that it has independently participated in the negotiation of the transactions contemplated hereby with the advice of its own counsel and advisors. Each Purchaser shall be entitled to independently protect and enforce its rights, including the rights arising out of this Agreement, and it shall not be necessary for any other Purchaser to be joined as an additional party in any proceeding for such purpose. Each Purchaser has been represented by its own separate legal counsel in its review and negotiation of this Agreement. The Company has elected to provide all Purchasers with the same terms for the convenience of the Company and not because it was required or requested to do so by any Purchaser. It is expressly understood that each provision contained in this Agreement is between the Company and a Purchaser, solely, and not between the Company and the Purchasers collectively and not between and among the Purchasers.

9.13 Termination. This Agreement shall terminate and be void and of no further force and effect, and all obligations of the parties hereunder shall terminate without any further liability on the part of any party in respect thereof, upon the earlier to occur of (i) such date and time that the Merger Agreement is terminated in accordance with its terms, (ii) if any of the conditions to Closing set forth in Section 6 are not satisfied or waived, or are not capable of being satisfied, on or prior to the Closing and, as a result thereof, the transactions contemplated hereby will not be and are not consummated at the Closing, (iii) upon mutual agreement of the Company and the Purchasers or (iv) if the Closing has not occurred on or before November 14, 2023, other than as a result of a Willful Breach of a Purchaser’s obligations hereunder; provided, however, that nothing herein shall relieve any party to this Agreement of any liability for common law fraud or for any Willful Breach of any representation, warranty, covenant, obligation or other provision contained in this Agreement. “Willful Breach” means a deliberate act or deliberate failure to act, taken with the actual knowledge that such act or failure to act would result in or constitute a material breach of this Agreement.

9.14 No Third-Party Beneficiaries. This Agreement is intended for the benefit of the parties hereto and their respective successors and permitted assigns and is not for the benefit of, nor may any provision hereof be enforced by, any other Person; provided, however, that each of the Placement Agents will be entitled to rely, as an express third-party beneficiary, on the representations and warranties of the Purchasers and the Company set forth in Section 3 and Section 4 hereof, respectively, and the covenants set forth in Section 5 hereof and Sections 9.04, 9.05, 9.08, 9.09, 9.10, 9.11, 9.12 and 9.13 hereof.

9.15 Arm’s Length Transactions. The Company acknowledges and agrees that (i) the transactions described in this Agreement are an arm’s-length commercial transaction between the parties, (ii) the Purchasers have not assumed nor will they assume an advisory or fiduciary responsibility in the Company’s favor with respect to any of the transactions contemplated by this Agreement or the process leading thereto, and the Purchasers have no obligation to the Company with respect to the transactions contemplated by this Agreement except those obligations expressly set forth in this Agreement, (iii) any advice given by any of the Purchasers or any of their respective representatives or agents in connection with the transactions described in this Agreement is merely incidental to such Purchaser’s purchase of its Securities, and (iv) the Company’s decision to enter into this Agreement and the Merger Agreement has been based solely on the independent evaluation by the Company and its representatives.

18

9.16 Interpretation. Wherever required by the context of this Agreement, the singular shall include the plural and vice versa, and the masculine gender shall include the feminine and neuter genders and vice versa, and references to any agreement, document or instrument shall be deemed to refer to such agreement, document or instrument as amended, supplemented or modified from time to time. All article, section, paragraph or clause references not attributed to a particular document shall be references to such parts of this Agreement, and all exhibit, annex, letter and schedule references not attributed to a particular document shall be references to such exhibits, annexes, letters and schedules to this Agreement. In addition, the word “or” is not exclusive; the words “including,” “includes,” “included” and “include” are deemed to be followed by the words “without limitation”; and the terms “herein,” “hereof” and “hereunder” and other words of similar import refer to this Agreement as a whole and not to any particular section, paragraph or subdivision.

9.17 Payment Set Aside. To the extent that the Company makes a payment or payments to any Purchaser pursuant to this Agreement or a Purchaser enforces or exercises its rights hereunder, and such payment or payments or the proceeds of such enforcement or exercise or any part thereof are subsequently invalidated, declared to be fraudulent or preferential, set aside, recovered from, disgorged by or are required to be refunded, repaid or otherwise restored to the Company, a trustee, receiver or any other Person under any law (including any bankruptcy law, state or federal law, common law or equitable cause of action), then to the extent of any such restoration the obligation or part thereof originally intended to be satisfied shall be revived and continued in full force and effect as if such payment had not been made or such enforcement or setoff had not occurred.

9.18 Adjustments in Share Numbers and Price. In the event of any stock split, subdivision, dividend or distribution payable in shares of Common Stock (or other securities or rights convertible into, or entitling the holder thereof to receive directly or indirectly shares of Common Stock), combination or other similar recapitalization or event occurring after the date hereof and prior to the Closing, each reference herein to a number of shares or a price per share shall be deemed to be amended to appropriately account for such event.

9.19 Production of this Agreement. The Company and each Purchaser is irrevocably authorized to produce this Agreement or a copy hereof to any interested party as requested or required by law, rule or regulation in any administrative or legal proceeding or official inquiry with respect to the matters covered hereby; provided that, with respect to production by the Company, such party will provide the Purchasers with at least three Business Days’ prior written notice of such production to the extent legally permissible and subject to Section 5.02.

[Signature pages follow]

19

SCHEDULE OF PURCHASERS

[Intentionally Omitted]

Exhibit A

Form of Registration Rights Agreement

[Intentionally Omitted]

Exhibit B

Opinion of Company Counsel

[Intentionally Omitted]

Exhibit C

Secretary Certificate

[Intentionally Omitted]

Schedule 4.03

Subsidiaries

[Intentionally Omitted]

Execution Version

Exhibit 10.2

REGISTRATION RIGHTS AGREEMENT

This Registration Rights Agreement (this “Agreement”) is made and entered into as of July 14, 2023, among Korro Bio, Inc., a Delaware corporation, Frequency Therapeutics, Inc. (“Frequency”), a Delaware corporation, and each of the several purchasers signatory hereto (each such purchaser, a “Purchaser” and. collectively, the “Purchasers”).

WHEREAS, the Company is party to that certain Agreement and Plan of Merger by and among the Company, Frequency Merger Sub Inc., and Frequency, dated as of the date hereof (the “Merger Agreement”), pursuant to which the Company will become a wholly-owned subsidiary of Frequency (the “Merger”);

WHEREAS, following the Effective Time (as defined in the Merger Agreement), Frequency will change its name to Korro Bio, Inc. (“TopCo”);

WHEREAS, the Company and the Purchasers are parties to a Subscription Agreement, dated as of the date hereof (the “Purchase Agreement”), pursuant to which the Purchasers, severally and not jointly, are purchasing, prior to the Effective Time, shares of Common Stock of the Company (the “Purchased Shares”); and

WHEREAS, in connection with the consummation of the transactions contemplated by the Purchase Agreement, and pursuant to the terms of the Purchase Agreement, the parties desire to enter into this Agreement in order to grant certain rights to the Purchasers as set forth below.

NOW, THEREFORE, in consideration of the mutual covenants and promises set forth herein, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereby agree as follows:

1. Definitions.

In addition to the terms defined herein, capitalized terms used and not otherwise defined herein that are defined in the Purchase Agreement shall have the meanings given such terms in the Purchase Agreement. As used in this Agreement, the following terms shall have the following meanings:

“Advice” shall have the meaning set forth in Section 6(c).

“Affiliate” means any Person that, directly or indirectly through one or more intermediaries, controls or is controlled by or is under common control with a Person, as such terms are used in and construed under Rule 405 under the Securities Act.

“Business Day” means any day except (a) a Saturday or Sunday or (b) any day on which banks in the City of New York are authorized or required by law or executive order to be closed; provided, however, that Lincoln’s Birthday (February 12) and Election Day shall not be excluded from the definition of Business Day by virtue of this clause (b).

“Commission” means the Securities and Exchange Commission.

“Common Stock” means TopCo’s common stock, par value $0.001 per share, and stock of any other class of securities into which such securities may hereafter be reclassified or changed.

“Company” means Korro Bio, Inc. for all periods prior to the Effective Time (as defined in the Merger Agreement) and TopCo for all periods after the Effective Time.

“Effective Time” shall have the meaning ascribed thereto in the Merger Agreement.

“Effectiveness Date” means, with respect to the Initial Registration Statement required to be filed hereunder, the 45th calendar day following the Effective Time (or, in the event of a “full review” by the Commission, the 90th calendar day following the Effective Time) and with respect to any additional Registration Statements that may be required pursuant to Sections 2(b) and 2(c) or Section 3(c), the 45th calendar day following the date on which an additional Registration Statement is required to be filed hereunder (or, in the event of a “full review” by the Commission, the 90th calendar day following the date of filing thereof); provided, however, that in the event the Company is notified by the Commission (orally or in writing) that one or more of the above Registration Statements will not be reviewed or is no longer subject to further review and comments, the Effectiveness Date as to such Registration Statement shall be the fifth (5th) Trading Day following the date on which the Company is so notified if such date precedes the dates otherwise required above, provided, further, if such Effectiveness Date falls on a day that is not a Trading Day, then the Effectiveness Date shall be the next succeeding Trading Day.

“Effectiveness Period” shall have the meaning set forth in Section 2(a).

“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

“Filing Date” means, with respect to the Initial Registration Statement required hereunder, the three Business Day following the Effective Time and, with respect to any additional Registration Statements that may be required pursuant to Sections 2(b) and 2(c) or Section 3(c), the 30th calendar day following the date on which the Company is permitted by SEC Guidance to file such additional Registration Statement related to the Registrable Securities.

“Holder” or “Holders” means the holder or holders, as the case may be, from time to time of Registrable Securities.

“Indemnified Party” shall have the meaning set forth in Section 5(c).

“Indemnifying Party” shall have the meaning set forth in Section 5(c).

“Initial Registration Statement” means the initial Registration Statement filed pursuant to this Agreement.

“Losses” shall have the meaning set forth in Section 5(a).

“Person” means an individual or corporation, partnership, trust, incorporated or unincorporated association, joint venture, limited liability company, joint stock company, government (or an agency or subdivision thereof) or other entity of any kind.

“Plan of Distribution” shall have the meaning set forth in Section 2(a).

“Prospectus” means the prospectus included in a Registration Statement (including, without limitation, a prospectus that includes any information previously omitted from a prospectus filed as part of an effective registration statement in reliance upon Rule 430A or Rule 430B promulgated by the Commission pursuant to the Securities Act), as amended or supplemented by any prospectus supplement, with respect to the terms of the offering of any portion of the Registrable Securities covered by a Registration Statement, and all other amendments and supplements to the Prospectus, including post-effective amendments, and all material incorporated by reference or deemed to be incorporated by reference in such Prospectus.

“Registrable Securities” means, as of any date of determination, (a) all shares of TopCo common stock issued to the Purchasers at the closing of the Merger in respect of the Purchased Shares (the “Purchase Agreement Shares”), (b) all shares of TopCo issued at the closing of the Merger to the Purchasers in respect of all other shares of capital stock of the Company held by Purchaser as of immediately prior to the Effective Time, and (c) any securities issued or then issuable upon any stock split, dividend or other distribution, recapitalization or similar event with respect to the foregoing; provided, however, that any such Registrable Securities shall cease to be Registrable Securities (and the Company shall not be required to maintain the effectiveness of any, or file another, Registration Statement hereunder with respect thereto) upon the earliest to occur of (i) a Registration Statement with respect to the sale of such Registrable Securities is declared effective by the Commission under the Securities Act and such Registrable Securities have been disposed of

2

by the Holder in accordance with such effective Registration Statement (in which case, only any such security sold or disposed of by the Holder shall cease to be a Registrable Security), (ii) such Registrable Securities have been previously sold in accordance with Rule 144 (in which case, only any such security sold or disposed of by the Holder shall cease to be a Registrable Security), (iii) such securities become eligible for resale without volume or manner-of-sale restrictions pursuant to Rule 144 and without the requirement for the Company to be in compliance with the current public information requirement under Rule 144, as reasonably determined by counsel to the Company.

“Registration Statement” means any registration statement required to be filed hereunder pursuant to Section 2(a) and any additional registration statements contemplated by Section 2(c) or Section 3(c), including (in each case) the Prospectus, amendments and supplements to any such registration statement or Prospectus, including pre- and post-effective amendments, all exhibits thereto, and all material incorporated by reference or deemed to be incorporated by reference in any such registration statement.

“Rule 144” means Rule 144 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended or interpreted from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same purpose and effect as such Rule.

“Rule 415” means Rule 415 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended or interpreted from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same purpose and effect as such Rule.

“Rule 424” means Rule 424 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended or interpreted from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same purpose and effect as such Rule.

“Rule 461” means Rule 461 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended or interpreted from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same purpose and effect as such Rule.

“SEC Guidance” means (i) any publicly-available written or oral guidance of the Commission staff, or any comments, requirements or requests of the Commission staff (whether or not publicly-available); provided, that any such oral guidance, comments, requirements or requests are reduced to writing by the Commission and (ii) the Securities Act.

“Selling Stockholder Questionnaire” shall have the meaning set forth in Section 3(a).

“Trading Day” means any day on which the Frequency common stock is traded on a National Exchange.

2. Shelf Registration.

(a) On or prior to each Filing Date, the Company shall prepare and file with the Commission a Registration Statement covering the resale of all of the Registrable Securities the resale of which is not then registered on an effective Registration Statement for an offering to be made on a continuous basis pursuant to Rule 415, or, if Rule 415 is not available for offers and sales of the Registrable Securities, by such other means of distribution of Registrable Securities as the Holders may reasonably specify. Each Registration Statement filed hereunder shall be on Form S-3 (except if the Company is not then eligible to register for resale the Registrable Securities on Form S-3, in which case such registration shall be on another appropriate form in accordance with the provisions of Section 2(d)), and shall contain (unless otherwise directed by Holders holding at least 85% of Registrable Securities) disclosure substantially in the form of the “Plan of Distribution” attached hereto as Annex A and the “Selling Stockholder” section substantially in the form of the attached hereto as Annex B. Subject to the terms of this Agreement, the Company shall use commercially reasonable efforts to cause a Registration Statement filed under this Agreement (including, without limitation, under Section 3(c)) to be declared effective under the Securities Act as promptly as possible after the filing thereof, but in any event no later than the applicable Effectiveness Date (including filing with the Commission a request for acceleration of effectiveness in accordance with Rule 461), and shall use its

3

reasonable best efforts to keep such Registration Statement continuously effective under the Securities Act until the earlier of (a) the date that all Registrable Securities covered by such Registration Statement (i) have been sold, thereunder or pursuant to Rule 144, or (ii) may be sold without volume or manner-of-sale restrictions pursuant to Rule 144 and without the requirement for the Company to be in compliance with the current public information requirement under Rule 144, as determined by the counsel to the Company pursuant to a written opinion letter to such effect, addressed and acceptable to the Company’s transfer agent and the affected Holders and (b) five years after the date of this Agreement (the “Effectiveness Period”). The Company shall telephonically request effectiveness of a Registration Statement as of 5:00 p.m. (New York City time) on a Trading Day. The Company shall notify the Holders via e-mail of the effectiveness of a Registration Statement or any post-effective amendment thereto promptly following, and in any event on the same Trading Day as, confirmation of effectiveness with the Commission. The Company shall within one Trading Day, in accordance with SEC Guidance file a final Prospectus with the Commission as required by Rule 424 and provide Holders with copies of the final Prospectus to be used in connection with the sale or other disposition of the securities covered thereby.

(b) Notwithstanding the registration obligations set forth in Section 2(a), if the Commission informs the Company that the resale of all of the Registrable Securities cannot, as a result of the application of Rule 415, be registered as a secondary offering on a single registration statement, the Company agrees to promptly inform each of the Holders thereof and use commercially reasonable efforts to file amendments to the Initial Registration Statement as required by the Commission, covering the maximum number of Registrable Securities permitted to be registered by the Commission, on Form S-3, if the Company is not then eligible to register the resale of the Registrable Securities on Form S-3, on such other form available to register for resale the Registrable Securities as a secondary offering; provided, however, that prior to filing such amendment, the Company shall be obligated to use commercially reasonable efforts to advocate with the Commission for the registration of the resale of all of the Registrable Securities in accordance with the SEC Guidance, including the Securities Act Rule Compliance and Disclosure Interpretations Question 612.09.

(c) Notwithstanding any other provision of this Agreement, if the Commission or any SEC Guidance sets forth a limitation on the number of Registrable Securities permitted to be registered on a particular Registration Statement as a secondary offering, including as a result of the application of Rule 415 (and notwithstanding that the Company used commercially reasonable efforts to advocate with the Commission for the registration of all or a greater portion of Registrable Securities), unless otherwise directed in writing by a Holder as to its Registrable Securities, the total number of Registrable Securities to be registered on such Registration Statement will be reduced as follows:

In the event of a cutback hereunder, the Company shall give the Holder at least two (2) Trading Days prior written notice along with the calculations as to such Holder’s allotment. In the event the Company amends the Initial Registration Statement in accordance with the foregoing, the Company will use its commercially reasonable efforts to file with the Commission, as promptly as allowed by the Commission or SEC Guidance provided to the Company or to registrants of securities in general, one or more registration statements on Form S-3 or, if the Company is not then eligible to register the resale of such Registrable Securities on Form S-3, such other form available to register the resale of those Registrable Securities that were not registered for resale on the Initial Registration Statement (the “Cut Back Shares”), as amended (the “Remainder

4

Registration Statement”). From and after such date as the Company is able to effect the registration of the resale of such Cut Back Shares in accordance with any Commission restrictions applicable to such Cut Back Shares (the “Restriction Termination Date”), all of the provisions of this Section 2(b) (including the Company’s obligations with respect to the filing of a Registration Statement and its obligations to use commercially reasonable efforts to have such Registration Statement declared effective within the time periods set forth herein) shall again be applicable to such Cut Back Shares; provided, however, that (i) the Filing Date for such Cut Back Shares shall be ten (10) Business Days after such Restriction Termination Date, and (ii) the date by which the Company is required to obtain effectiveness with respect to such Cut Back Shares shall be the 30th calendar day immediately after the Restriction Termination Date (or the 60th calendar day if the Commission reviews and provides written comments on such Remainder Registration Statement).

(d) If Form S-3 is not available for the registration of the resale of Registrable Securities hereunder, the Company shall (i) register the resale of the Registrable Securities on another appropriate form and (ii) undertake to register the Registrable Securities on Form S-3 as soon as such form is available, provided that the Company shall maintain the effectiveness of the Registration Statement then in effect until such time as a Registration Statement on Form S-3 covering the resale of the Registrable Securities has been declared effective by the Commission.

(e) In no event shall any Holder be identified as a statutory underwriter in any Registration Statement (including a Remainder Registration Statement); provided, that if the Commission requires that a Holder be identified as a statutory underwriter in a Registration Statement, such Holder will have the option, in its sole and absolute discretion, to either (i) have the opportunity to withdraw from such Registration Statement upon its prompt written request to the Company or (ii) be included as such in the Registration Statement.

3. Registration Procedures.

In connection with the Company’s registration obligations hereunder, the Company shall:

(a) Not less than five (5) Trading Days prior to the filing of each Registration Statement and not less than one (1) Trading Day prior to the filing of any related Prospectus or any amendment or supplement thereto (including any document that would be incorporated or deemed to be incorporated therein by reference), the Company shall (i) furnish to each Holder copies of all such documents proposed to be filed, which documents (other than those incorporated or deemed to be incorporated by reference) will be subject to the review of such Holders, and (ii) use commercially reasonable efforts to cause its officers and directors, counsel and independent registered public accountants to respond to such inquiries as shall be necessary, in the reasonable opinion of respective counsel to each Holder, to conduct a reasonable investigation within the meaning of the Securities Act. The Company shall not file a Registration Statement or any such Prospectus or any amendments or supplements thereto to which the Required Holders (as defined below) or any Holder with respect to information about itself included in such Registration Statement, Prospectus or any amendments or supplements thereto shall reasonably object in good faith, provided that, the Company is notified of such objection in writing no later than three (3) Trading Days after the Holders have been so furnished copies of a Registration Statement or one (1) Trading Day after the Holders have been so furnished copies of any related Prospectus or amendments or supplements thereto. Each Holder agrees to furnish to the Company a completed questionnaire in the form attached to this Agreement as Annex C or such other form as reasonably acceptable to the Company (a “Selling Stockholder Questionnaire”) on a date that is not less than two (2) Trading Days prior to the Filing Date or by the end of the third (3rd) Trading Day following the date on which such Holder receives draft materials in accordance with this Section. The Company shall not be required to include any Registrable Securities in the Registration Statement for any Holder that has not provided such Selling Stockholder Questionnaire.

(b) (i) Prepare and file with the Commission such amendments, including post-effective amendments, to a Registration Statement and the Prospectus used in connection therewith as may be necessary to keep a Registration Statement continuously effective as to the applicable Registrable Securities for the Effectiveness Period and prepare and file with the Commission such additional Registration Statements in order to register for resale under the Securities Act all of the Registrable Securities, (ii) cause

5

the related Prospectus to be amended or supplemented by any required Prospectus supplement (subject to the terms of this Agreement), and, as so supplemented or amended, to be filed pursuant to Rule 424, (iii) respond as promptly as reasonably possible to any comments received from the Commission with respect to a Registration Statement or any amendment thereto and, upon request of Holders, provide as promptly as reasonably possible to the Holders true and complete copies of all correspondence from and to the Commission relating to a Registration Statement (provided that, the Company shall excise any information contained therein that would constitute material non-public information regarding the Company or any of its subsidiaries), and (iv) comply in all material respects with the applicable provisions of the Securities Act and the Exchange Act with respect to the disposition of all Registrable Securities covered by a Registration Statement during the applicable period in accordance (subject to the terms of this Agreement) with the intended methods of disposition by the Holders thereof set forth in such Registration Statement as so amended or in such Prospectus as so supplemented.

(c) If during the Effectiveness Period, the number of Registrable Securities at any time exceeds 100% of the number of shares of Common Stock then registered in a Registration Statement, then the Company shall, subject to Sections 2(b) and 2(c), if applicable, file as soon as reasonably practicable and thereafter cause to be declared effective under the Securities Act, an additional Registration Statement that, together with the existing Registration Statements, covers the resale by the Holders of not less than the number of such Registrable Securities.

(d) Notify the Holders of Registrable Securities to be sold (which notice, if given pursuant to clauses (iii) through (v) hereof, shall be accompanied by an instruction to suspend the use of the Prospectus until the requisite changes have been made) as promptly as reasonably possible (and, in the case of (i)(A) below, not less than one (1) Trading Day prior to such filing) and (if requested by any such Person) confirm such notice in writing no later than one (1) Trading Day following the day (i)(A) when a Prospectus or any Prospectus supplement or post-effective amendment to a Registration Statement is proposed to be filed, (B) when the Commission notifies the Company whether there will be a “review” of such Registration Statement and whenever the Commission comments in writing on such Registration Statement, and (C) with respect to a Registration Statement or any post-effective amendment, when the same has become effective, (ii) of any request by the Commission or any other federal or state governmental authority for amendments or supplements to a Registration Statement or Prospectus or for additional information, (iii) of the issuance by the Commission or any other federal or state governmental authority of any stop order suspending the effectiveness of a Registration Statement covering any or all of the Registrable Securities or the initiation of any Proceeding for that purpose, (iv) of the receipt by the Company of any notification with respect to the suspension of the qualification or exemption from qualification of any of the Registrable Securities for sale in any jurisdiction, or the initiation or threatening of any action, suit, proceeding, inquiry or investigation before or brought by any Governmental Entity (a “Proceeding”) for such purpose, and (v) of the occurrence of any event or passage of time that makes the financial statements included or incorporated by reference in a Registration Statement ineligible for inclusion or incorporation by reference therein or any statement made in a Registration Statement or Prospectus or any document incorporated or deemed to be incorporated therein by reference untrue in any material respect or that requires any revisions to a Registration Statement, Prospectus or other documents so that, in the case of a Registration Statement or the Prospectus, as the case may be, it will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading; provided, however, that, notwithstanding any other provision in this Section 3(d), in no event shall any such notice contain any information that would constitute material, non-public information regarding the Company or any of its subsidiaries.

(e) Use its commercially reasonable efforts to avoid the issuance of, or, if issued, obtain the withdrawal of (i) any order stopping or suspending the effectiveness of a Registration Statement, or (ii) any suspension of the qualification (or exemption from qualification) of any of the Registrable Securities for sale in any jurisdiction, at the earliest practicable moment.

6

(f) If requested by a Holder, furnish to each Holder, without charge, an electronic copy of the conformed copy of each such Registration Statement and each amendment thereto, including financial statements and schedules, all documents incorporated or deemed to be incorporated therein by reference to the extent requested by such Person, and all exhibits to the extent requested by such Person (including those previously furnished or incorporated by reference) promptly after the filing of such documents with the Commission, provided that any such item that is available on the EDGAR system (or successor thereto) need not be furnished.

(g) Subject to the terms of this Agreement, the Company hereby consents to the use of such Prospectus and each amendment or supplement thereto by each of the selling Holders in connection with the offering and sale of the Registrable Securities covered by such Prospectus and any amendment or supplement thereto, except after the giving of any notice pursuant to Section 3(d)(iii) through (v).

(h) Prior to any resale of Registrable Securities by a Holder, use its commercially reasonable efforts to register or qualify or cooperate with the selling Holders in connection with the registration or qualification (or exemption from the registration or qualification) of such Registrable Securities for the resale by the Holder under the securities or Blue Sky laws of such jurisdictions within the United States as any Holder reasonably requests in writing, to keep each registration or qualification (or exemption therefrom) effective during the Effectiveness Period and to do any and all other acts or things reasonably necessary to enable the disposition in such jurisdictions of the Registrable Securities covered by each Registration Statement, provided that the Company shall not be required to qualify generally to do business in any jurisdiction where it is not then so qualified, subject the Company to any material tax in any such jurisdiction where it is not then so subject or file a general consent to service of process in any such jurisdiction.

(i) Upon the occurrence of any event contemplated by Section 3(d)(iii) through (v), as promptly as reasonably possible, prepare a supplement or amendment, including a post-effective amendment, to a Registration Statement or a supplement to the related Prospectus or any document incorporated or deemed to be incorporated therein by reference, and file any other required document so that, as thereafter delivered, neither a Registration Statement nor such Prospectus will contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading. If the Company notifies the Holders in accordance with clauses (iii) through (v) of Section 3(d) above to suspend the use of any Prospectus until the requisite changes to such Prospectus have been made, then the Holders shall suspend use of such Prospectus; provided that the Company shall only be entitled to exercise its right under this Section 3(j) to suspend the availability of a Registration Statement and Prospectus up to two (2) occasions in any 12-month period for a period not to exceed 45 consecutive days or a total of ninety (90) calendar days, in each case in any such 12- month period. The Company will use its reasonable best efforts to ensure that the use of the Prospectus may be resumed as promptly as is reasonably practicable. In the event the Company files a Registration Statement on a form other than Form S-3, as permitted hereunder, the Company’s rights under this Section 3(j) shall include suspensions of availability arising from the filing of a post-effective amendment to a Registration Statement to update the Prospectus therein to include the information contained in the Company’s Annual Report on Form 10-K, which suspensions may extend for the amount of time reasonably required to respond to any comments of the staff of the Commission on such amendment.

(j) Otherwise use commercially reasonable efforts to comply with all applicable rules and regulations of the Commission under the Securities Act and the Exchange Act, including, without limitation, Rule 172 under the Securities Act, file any final Prospectus, including any supplement or amendment thereof, with the Commission pursuant to Rule 424 under the Securities Act, promptly inform the Holders in writing if, at any time during the Effectiveness Period, the Company does not satisfy the conditions specified in Rule 172 and, as a result thereof, the Holders are required to deliver a Prospectus in connection with any disposition of Registrable Securities and take such other actions as may be reasonably necessary to facilitate the registration of the resale of the Registrable Securities hereunder.

(k) The Company may require each selling Holder to furnish to the Company a statement as to the number of shares of Common Stock beneficially owned by such Holder and, if required by the Commission, the natural persons thereof that have voting and dispositive control over the shares.

(l) The Company shall use its commercially reasonable efforts to maintain eligibility for use of Form S-3 (or any successor form thereto) for the registration of the resale of the Registrable Securities once eligible to use such form.

7

(m) The Company shall use its reasonable best efforts to cause all Registrable Securities to be listed on each securities exchange or market, if any, on which the shares of Frequency common stock are listed.

(n) The Company shall, at its sole expense, upon appropriate notice from a Holder stating that Registrable Securities have been sold or transferred pursuant to an effective Registration Statement, promptly (and in any event within two (2) Trading Days of such notice) prepare and deliver certificates or evidence of book-entry positions representing the Registrable Securities to be delivered to a transferee pursuant to such Registration Statement, which certificates or book-entry positions shall be free of any restrictive legends and in such denominations and registered in such names as the undersigned may request. Further, the Company shall upon appropriate notice and receipt of customary representations from a Holder (i) following any sale of the Purchased Shares pursuant to Rule 144 or any other applicable exemption from the registration requirements of the Securities Act, or (ii) if the Purchased Shares are eligible for resale under Rule 144(b)(1) or any successor provision, use commercially reasonable efforts to promptly (and in any event within two (2) Trading Days after such notice) cause the restrictive legends to be removed and prepare and deliver certificate(s) or evidence of book-entry positions that are free from all restrictive and other legends or, at the request of the Holder, via DWAC transfer to such Holder’s account.

(o) With a view to making available to the Purchasers the benefits of Rule 144 (or its successor rule) and any other rule or regulation of the Commission that may at any time permit the Purchasers to sell shares of Common Stock to the public without registration, the Company covenants and agrees to: (i) make and keep adequate current public information available, as those terms are understood and defined in Rule 144, until the earlier of (A) six months after such date as all of the Registrable Securities may be sold without restriction by the holders thereof pursuant to Rule 144 or any other rule of similar effect or (B) such date as all of the Registrable Securities shall have been resold; (ii) file with the Commission in a timely manner all reports and other documents required of the Company under the 1934 Act; and (iii) furnish to each Purchaser upon reasonable request, as long as such Purchaser owns any Registrable Securities, (A) a written statement by the Company that it has complied with the reporting requirements of the Exchange Act, and (B) such other information as may be reasonably requested in order to avail such Purchaser of any rule or regulation of the Commission that permits the selling of any such Registrable Securities without registration

4. Registration Expenses. All fees and expenses incident to the performance of or compliance with this Agreement by the Company shall be borne by the Company whether or not any Registrable Securities are sold pursuant to a Registration Statement. The fees and expenses referred to in the foregoing sentence shall include, without limitation, (i) all registration and filing fees (including, without limitation, fees and expenses of the Company’s counsel and independent registered public accountants) (A) with respect to filings made with the Commission, (B) with respect to filings required to be made with any National Exchange on which the Common Stock is then listed for trading, and (C) in compliance with applicable state securities or Blue Sky laws reasonably agreed to by the Company in writing (including, without limitation, fees and disbursements of counsel for the Company in connection with Blue Sky qualifications or exemptions of the Registrable Securities), (ii) printing expenses (including, without limitation, expenses of printing certificates for Registrable Securities), (iii) messenger, telephone and delivery expenses, (iv) fees, expenses and disbursements of counsel for the Company, (v) Securities Act liability insurance, if the Company so desires such insurance, (vi) fees and expenses of all other Persons retained by the Company in connection with the consummation of the transactions contemplated by this Agreement, including the Company’s transfer agent, and (vii) in connection with the review and filing of any Registration Statement, the reasonable fees, expenses and disbursements, of one counsel for Citadel CEMF Investments Ltd., any of its Affiliates or its investment advisor. In addition, the Company shall be responsible for all of its internal expenses incurred in connection with the consummation of the transactions contemplated by this Agreement (including, without limitation, all salaries and expenses of its officers and employees performing legal or accounting duties), the expense of any annual audit and the fees and expenses incurred in connection with the listing of the Registrable Securities on any securities exchange as required hereunder. In no event shall the Company be responsible for any underwriting, broker or similar fees or commissions of any Holder or, except to the extent provided for in the Purchase Agreement or this Agreement, any legal fees or other costs of the Holders (except as set forth in clause the foregoing clause (vii)).

8

5. Indemnification.

(a) Indemnification by the Company. The Company shall, notwithstanding any termination of this Agreement, indemnify, defend and hold harmless each Holder and its Affiliates and each of their respective directors, officers, stockholders, equity holders (regardless of whether such interests are held directly or indirectly), members, partners, principals, managers, portfolio managers, trustees, employees, investment advisors, agents and other representatives, predecessors, successors and assigns, subsidiaries, attorneys, advisors, (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding a lack of such title or any other title), each Person who controls such Purchaser or any Affiliate thereof (within the meaning of Section 15 of the Securities Act and Section 20 of the Exchange Act) and the directors, officers, stockholders, equity holders (regardless of whether such interests are held directly or indirectly), members, partners, principals, managers, portfolio managers, trustees, employees, investment advisors, agents and other representatives, predecessors, successors and assigns, subsidiaries, attorneys, advisors, (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding a lack of such title or any other title) of each such controlling persons (each, a “Holder Indemnified Person”), to the fullest extent permitted by applicable law, from and against any and all losses, liabilities, obligations, actions, suits, proceedings, investigations, inquiries, claims, contingencies, damages, costs and expenses, including all judgments, amounts paid in settlements, court costs and reasonable attorneys’ fees and expenses and disbursements of external counsel and costs of investigation (collectively, “Losses”), joint or several, that any Holder Indemnified Person may suffer or incur in connection with, arising out of, as a result of, relating to or based upon (1) any untrue or alleged untrue statement of a material fact contained in a Registration Statement, any Prospectus or any form of prospectus or in any amendment or supplement thereto or in any preliminary prospectus, or arising out of or relating to any omission or alleged omission of a material fact required to be stated therein or necessary to make the statements therein (in the case of any Prospectus or form of prospectus or supplement thereto, in light of the circumstances under which they were made) not misleading or (2) any violation or alleged violation by the Company or its agents of the Securities Act, the Exchange Act or any state securities law, or any rule or regulation thereunder, in connection with the performance or non-performance of its obligations under this Agreement or any action or inaction required of the Company in connection with any registration, except to the extent, but only to the extent, that (i) such untrue statements, alleged untrue statements or omissions are based upon information regarding such Holder furnished in writing to the Company by such Holder expressly for use therein, or to the extent that such information relates to such Holder or such Holder’s proposed method of distribution of Registrable Securities and was reviewed and expressly approved in writing by such Holder expressly for use in a Registration Statement, such Prospectus or in any amendment or supplement thereto (it being understood that the Holder has approved Annex A hereto for this purpose) or (ii) in the case of an occurrence of an event of the type specified in Section 3(d)(iii)-(v), the use by such Holder of an outdated, defective or otherwise unavailable Prospectus after the Company has notified such Holder in writing that the Prospectus is outdated, defective or otherwise unavailable for use by such Holder and prior to the receipt by such Holder of the Advice contemplated in Section 6(c), and will reimburse such Holder Indemnified Person for legal and other expenses reasonably incurred as such expenses are incurred by such Holder Indemnified Person in connection with investigating, defending, preparing to defend, providing evidence in, preparing to serve or serving as a witness with respect to, settling, compromising or paying such Loss. The Company shall notify the Holders promptly of the institution, threat or assertion of any Proceeding in connection with, arising out of, as a result of, relating to or based on arising from or in connection with the transactions contemplated by this Agreement of which the Company is aware. Such indemnity shall remain in full force and effect regardless of any investigation made by or on behalf of such indemnified person and shall survive the transfer of any Registrable Securities by any of the Holders in accordance with Section 6(f).

(b) Indemnification by Holders. Each Holder shall, severally and not jointly, indemnify, defend and hold harmless the Company and its Affiliates and each of their respective directors, officers, stockholders, equity holders (regardless of whether such interests are held directly or indirectly), members, partners, principals, managers, portfolio managers, trustees, employees, investment advisors, agents and other representatives, predecessors, successors and assigns, subsidiaries, attorneys, advisors, (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding a lack of such title or any other title), each Person who controls the Company or any Affiliate thereof (within the meaning of Section 15 of the Securities Act and Section 20 of the Exchange Act) and the directors, officers, stockholders, equity holders (regardless of whether such interests are held directly or indirectly), members, partners, principals, managers, portfolio managers, trustees, employees, investment advisors, agents and other

9

representatives, predecessors, successors and assigns, subsidiaries, attorneys, advisors, (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding a lack of such title or any other title) of each such controlling persons (each a “Company Indemnified Person”), to the fullest extent permitted by applicable law, from and against any and all Losses, the extent arising out of, as a result of, relating to or based upon any untrue or alleged untrue statement of a material fact contained in any Registration Statement, any Prospectus, or in any amendment or supplement thereto or in any preliminary prospectus, or arising out of or relating to any omission or alleged omission of a material fact required to be stated therein or necessary to make the statements therein (in the case of any Prospectus or supplement thereto, in light of the circumstances under which they were made) not misleading to the extent, but only to the extent, that such untrue statement or omission is contained in any information regarding such Holder so furnished in writing by such Holder to the Company expressly for inclusion in such Registration Statement or such Prospectus or regarding the proposed method of distribution of Registrable Securities that was reviewed and expressly approved in writing by such Holder expressly for use in a Registration Statement (it being understood that the Holder has approved Annex A hereto for this purpose), such Prospectus or in any amendment or supplement thereto. In no event shall the aggregate liability of a selling Holder under this Section 5(b) and Section 5(d) be greater in amount than the dollar amount of the proceeds (net of all expenses paid by such Holder in connection with any claim relating to this Section 5 and the amount of any damages such Holder has otherwise been required to pay by reason of such untrue statement or omission) received by such Holder upon the sale of the Registrable Securities included in the Registration Statement giving rise to such indemnification obligation.

(c) Conduct of Indemnification Proceedings. If any Proceeding, demand, claim or shall be brought or asserted against, or any circumstance shall exist which would or might give rise to a demand or claim or the commencement of any Proceeding against, any Person entitled to indemnity hereunder (an “Indemnified Party”), such Indemnified Party shall promptly notify the Person from whom indemnity is sought (the “Indemnifying Party”) in writing, and the Indemnifying Party shall assume the defense thereof, including the employment of counsel reasonably satisfactory to the Indemnified Party and the payment of all reasonable fees and expenses incurred relating to or in connection with defense thereof, provided that the failure of any Indemnified Party to give such notice shall not relieve the Indemnifying Party of its obligations or liabilities pursuant to this Agreement, except (and only) to the extent that it shall be finally determined by a court of competent jurisdiction (which determination is not subject to appeal or further review) that such failure shall have materially and adversely prejudiced the Indemnifying Party.

An Indemnified Party shall have the right to employ separate counsel in any such Proceeding and to participate in the defense thereof, but the fees and expenses of such counsel shall be at the expense of such Indemnified Party or Parties unless: (1) the Indemnifying Party has agreed in writing to pay such fees, expenses and disbursements, (2) the Indemnifying Party shall have failed promptly to assume the defense of such Proceeding and to employ counsel reasonably satisfactory to such Indemnified Party in any such Proceeding, or (3) in the reasonable judgment of counsel to such Indemnified Party, representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. In the event of the circumstances described in the foregoing clauses (1)-(3), the fees, expenses and disbursements of such separate counsel and other expenses related to such participation shall be reimbursed by the Indemnifying Party as incurred. If such Indemnified Party notifies the Indemnifying Party in writing that it elects to employ separate counsel at the expense of the Indemnifying Party, the Indemnifying Party shall not have the right to assume the defense thereof and the reasonable fees and expenses of no more than one separate counsel shall be at the expense of the Indemnifying Party. Notwithstanding anything in this Section 5, the Indemnifying Party shall not be liable for any settlement of or entry of any judgment with respect to any such Proceeding effected without its written consent, which consent shall not be unreasonably withheld or delayed. No Indemnifying Party shall, without the prior written consent of the Indemnified Party, effect any settlement of or consent to the entry of any judgment with respect to any pending Proceeding in respect of which any Indemnified Party is or could have been a party and indemnity could have been sought hereunder by such Indemnified Party, unless such settlement or judgment (i) imposes no liability or obligation on the Indemnified Party, (ii) includes an unconditional release from the party bringing such indemnified claims of such Indemnified Party from all liability in respect of or arising out of on such claims or Proceedings or claims or Proceedings that are the subject matter of such Proceeding and (iii) does not include any admission of fault, culpability, wrongdoing or malfeasance by or on behalf of the Indemnified Party.

10

Subject to the terms of this Agreement, all reasonable and documented fees and expenses of the Indemnified Party (including reasonable and documented fees and expenses to the extent incurred in connection with investigating or preparing to defend such Proceeding in a manner not inconsistent with this Section) shall be paid to the Indemnified Party, as incurred, within ten (10) Trading Days of written notice thereof to the Indemnifying Party, provided that the Indemnified Party shall promptly reimburse the Indemnifying Party for that portion of such fees and expenses applicable to such actions for which such Indemnified Party is finally determined by a court of competent jurisdiction (which determination is not subject to appeal or further review) not to be entitled to indemnification hereunder.

(d) Contribution. If the indemnification under Section 5(a) or 5(b) is unavailable to an Indemnified Party or insufficient to hold an Indemnified Party harmless in respect of any Losses, then each Indemnifying Party shall contribute to the amount paid or payable by such Indemnified Party as a result of such Loss in such proportion as is appropriate to reflect the relative fault of the Indemnifying Party and Indemnified Party in connection with the actions, statements or omissions that resulted in such Losses, as well as any other relevant equitable considerations. The relative fault of such Indemnifying Party and Indemnified Party shall be determined by reference to, among other things, whether any action in question, including any untrue or alleged untrue statement of a material fact or omission or alleged omission of a material fact, has been taken or made by (or not taken or made by, in the case of an omission), or relates to information supplied by (or not supplied by, in the case of an omission), or on behalf of, such Indemnifying Party or Indemnified Party, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such action, statement or omission; provided, however, that no Person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) will be entitled to contribution from any Person who was not guilty of such fraudulent misrepresentation. The amount paid or payable by a party as a result of any Losses shall be deemed to include, subject to the limitations set forth in this Agreement, any legal or other fees, charges or expenses incurred by such party in connection with any Proceeding to the extent such party would have been indemnified for such fees or expenses if the indemnification provided for in this Section was available to such party in accordance with its terms.

The parties hereto agree that it would not be just and equitable if contribution pursuant to this Section 5(d) were determined by pro rata allocation or by any other method of allocation that does not take into account the equitable considerations referred to in the immediately preceding paragraph. In no event shall the contribution obligation of a Holder of Registrable Securities be greater in amount than the dollar amount of the proceeds (net of all expenses paid by such Holder in connection with any claim relating to this Section 5 and the amount of any damages such Holder has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission) received by it upon the sale of the Registrable Securities giving rise to such contribution obligation.

The indemnity and contribution agreements contained in this Section 5(d) are in addition to any liability that the Indemnifying Parties may have to the Indemnified Parties and are not in diminution or limitation of the indemnification provisions under the Purchase Agreement. Notwithstanding the foregoing sentence, in no event shall the aggregate liability of a selling Holder under this Section 5(b) and Section 5(d) be greater in amount than the dollar amount of the proceeds (net of all expenses paid by such Holder in connection with any claim relating to this Section 5 and the amount of any damages such Holder has otherwise been required to pay by reason of such untrue statement or omission) received by such Holder upon the sale of the Registrable Securities included in the Registration Statement giving rise to such indemnification obligation.

6. Miscellaneous.

(a) Cumulative Remedies; Specific Performance. None of the rights, powers or remedies conferred upon each Holder, on the one hand, or the Company, on the other hand, shall be mutually exclusive, and each such right, power or remedy shall be cumulative and in addition to every other right, power or remedy, whether conferred by this Agreement or now or hereafter available at law, in equity, by statute or otherwise. Each of the Holders and the Company acknowledges and agrees that, in view of the uniqueness of the securities referenced herein and the transactions contemplated hereby, money damages will not provide an adequate remedy at law if this Agreement is not performed in accordance with its terms, and therefore agrees that, in addition to being entitled to exercise all rights provided hereunder or granted by law, including

11

recovery of damages (money or otherwise), each of the Holders shall be entitled to specific performance under this Agreement, without the requirement of either proving the inadequacy of monetary damages as a remedy (or irreparable harm) or the posting of a bond. The Company hereby agrees to waive in any action for specific performance of any obligation the defense that a remedy at law would be inadequate.

(b) No Piggyback on Registrations; Prohibition on Filing Other Registration Statements. Neither the Company nor any of its security holders (other than the Holders in such capacity pursuant hereto) may include securities of the Company in any Registration Statements other than the Registrable Securities. The Company shall not file any other registration statements or enter into any agreement providing any such right to any holder of Company securities until all Registrable Securities are registered pursuant to a Registration Statement that is declared effective by the Commission, provided that this Section 6(b) shall not prohibit the Company from filing amendments to registration statements filed prior to the date of this Agreement so long as no new securities are registered on any such existing registration statements, nor preparing and filing with the Commission a registration statements on Form S-8 relating to its equity incentive plans.

(c) Discontinued Disposition. By its acquisition of Registrable Securities, each Holder agrees that, upon receipt of a notice from the Company of the occurrence of any event of the kind described in Section 3(d)(iii) through (v), such Holder will, subject to the limitations on suspension of the use of a Registration Statement or Prospectus contained therein set forth in Section 3(j), forthwith discontinue disposition of such Registrable Securities under a Registration Statement until it is advised in writing (the “Advice”) by the Company that the use of the applicable Prospectus (as it may have been supplemented or amended) may be resumed (such period, an “Allowable Suspension”). The Company will use its commercially reasonable efforts to ensure that the use of the Prospectus may be resumed as promptly as is practicable.

(d) Waivers and Amendments. Neither this Agreement, nor any provision hereof, may be changed, waived, amended or modified orally or by course of dealing, but only by an instrument in writing executed by the Company and the Required Holders, provided that, (a) if any, change, waiver, amendment, modification disproportionately and adversely impacts a Holder (or a subset of Holders), the consent of such disproportionately impacted Holder (or each Holder within such subset of Holders ) shall be required, (b) any amendment, modification or waiver of Section 5 shall require the consent of each Holder affected by such amendment, modification or waiver, and (c) the consent of all Holders is required for any amendment or modification that creates or imposes new or additional obligations on the Holders, including, without limitation, any lockup agreement. No waiver of any default with respect to any provision, condition or requirement of this Agreement shall be deemed to be a continuing wavier in the future or a waiver of any subsequent default or a waiver of any other provision, condition or requirement hereof, nor shall any delay or omission of any party to exercise any right hereunder in any manner impair the exercise of any such right. If a Registration Statement does not register all of the Registrable Securities pursuant to a waiver or amendment done in compliance with the previous sentence, then the number of Registrable Securities to be registered for each Holder shall be reduced pro rata among all Holders and each Holder shall have the right to designate which of its Registrable Securities shall be omitted from such Registration Statement. Notwithstanding the foregoing, a waiver or consent to depart from the provisions hereof with respect to a matter that relates exclusively to the rights of a Holder or some Holders and that does not directly or indirectly affect the rights of other Holders may be given only by such Holder or Holders of all of the Registrable Securities to which such waiver or consent relates; provided, however, that the provisions of this sentence may not be amended, modified, or supplemented except in accordance with the provisions of the first sentence of this Section 6(d). No consideration shall be offered or paid to any Person to amend or consent to a waiver or modification of any provision of this Agreement unless the same consideration also is offered to all of the parties to this Agreement. As used herein, “Required Holders” means (i) Holders of 50.1% or more of the then outstanding Registrable Securities (for purposes of clarification, this includes any securities issuable upon conversion or exercise of any Registrable Security) and (ii) any Holder (together with its affiliated funds) who initially purchased at least $14,900,000 of Purchase Agreement Shares.

(e) Notices. Any and all notices or other communications or deliveries required or permitted to be provided hereunder shall be delivered as set forth in the Purchase Agreement.

12

(f) Successors and Assigns. All the terms and provisions of this Agreement shall be binding upon and inure to the benefit of and be enforceable by the respective parties hereto, the successors and permitted assigns of each Holder and the successors of the Company, whether so expressed or not. None of the Holder may assign its rights or obligations hereunder without the prior written consent of the Company, except as permitted under the Purchase Agreement. The Company may not assign its rights or obligations hereunder without the consent of the Required Holders. This Agreement shall not inure to the benefit of or be enforceable by any other person.

(g) No Inconsistent Agreements. Neither the Company nor any of its subsidiaries has entered, as of the date hereof, nor shall the Company or any of its subsidiaries, on or after the date of this Agreement, enter into any agreement with respect to its securities, that would have the effect of impairing the rights granted to the Holders in this Agreement or otherwise conflicts with the provisions hereof. Neither the Company nor any of its subsidiaries has previously entered into any agreement granting any registration rights with respect to any of its securities to any Person that have not been satisfied in full.

(h) Execution and Counterparts. This Agreement may be executed in any number of counterparts and by different parties hereto in separate counterparts, with the same effect as if all parties had signed the same document. All such counterparts (including counterparts delivered by facsimile or other electronic format) shall be deemed an original, shall be construed together and shall constitute one and the same instrument. This Agreement shall become effective when each party hereto shall have received counterparts hereof signed by all of the other parties hereto.

(i) Governing Law. All questions concerning the construction, validity, enforcement and interpretation of this Agreement shall be determined in accordance with the provisions of the Purchase Agreement and Section 9.07 is hereby incorporated herein mutatis mutandi.

(j) [Reserved].

(k) Severability. If any provision of this Agreement shall be found by any court of competent jurisdiction to be invalid or unenforceable, the parties hereby waive such provision to the extent that it is found to be invalid or unenforceable. Such provision shall, to the maximum extent allowable by law, be modified by such court so that it becomes enforceable, and, as modified, shall be enforced as any other provision hereof, all the other provisions hereof continuing in full force and effect.

(l) Headings. The headings of the Sections and paragraphs of this Agreement have been inserted for convenience of reference only and do not constitute a part of this Agreement.

(m) Independent Nature of Holders’ Obligations and Rights. The obligations of each Holder under this Agreement are several and not joint with the obligations of any other Holder, and no Holder shall be responsible in any way for the performance or non-performance of the obligations of any other Holder under this Agreement. Each Holder acknowledges that no other Holder has acted as agent for such Holder in connection with making its investment hereunder and that no Holder will be acting as agent of such Holder in connection with monitoring its investment in the Purchased Shares or enforcing its rights under this Agreement. Nothing contained herein, and no action taken by any Holder pursuant hereto, shall be deemed to constitute the Holders as, and the Company acknowledges that the Holders do not so constitute, a partnership, an association, a joint venture or any other kind of entity, or create a presumption that the Holders are in any way acting in concert or as a group (including a “group” within the meaning of Section 13(d)(3) of the 1934 Act), and the Company will not assert any such claim with respect to such obligations or the transactions contemplated by this Agreement, and the Company acknowledges that the Holders are not acting in concert or as a group with respect to such obligations or the transactions contemplated by this Agreement. The Company acknowledges and each Holder confirms that it has independently participated in the negotiation of the transactions contemplated hereby with the advice of its own counsel and advisors. Each Holder shall be entitled to independently protect and enforce its rights, including the rights arising out of this Agreement, and it shall not be necessary for any other Holder to be joined as an additional party in any proceeding for such purpose. Each Holder has been represented by its own separate legal counsel in its review and negotiation of this Agreement. The Company has elected to provide all Holders with the same terms for the convenience of the Company and not because it was required or requested to do so by any Holder. It is

13

expressly understood that each provision contained in this Agreement is between the Company and a Holder, solely, and not between the Company and the Holders collectively and not between and among the Holders.

(Signature Pages Follow)

14

Annex A

Plan of Distribution

Each selling stockholder of the securities and any of their pledgees, assignees, donees, transferees or other successors-in-interest (each a “Selling Stockholder” and collectively, the “Selling Stockholders”) may, from time to time, sell, transfer or otherwise dispose of any or all of their securities covered hereby on the Nasdaq Global Select Market, the Nasdaq Global Market, the Nasdaq Capital Market, or the New York Stock Exchange or any other stock exchange, market or trading facility on which the securities are traded or in private transactions. These sales may be at fixed or negotiated prices. A Selling Stockholder may use any one or more of the following methods when selling securities:

The Selling Stockholders may also sell securities under Rule 144 or any other exemption from registration under the Securities Act of 1933, as amended (the “Securities Act”), if available, rather than under this prospectus.

Broker-dealers engaged by the Selling Stockholders may arrange for other brokers-dealers to participate in sales. Broker-dealers may receive commissions or discounts from the Selling Stockholders (or, if any broker-dealer acts as agent for the purchaser of securities, from the purchaser) in amounts to be negotiated, but, except as set forth in a supplement to this Prospectus, in the case of an agency transaction not in excess of a customary brokerage commission in compliance with FINRA Rule 2121; and in the case of a principal transaction a markup or markdown in compliance with FINRA Rule 2121.

In connection with the sale of the securities or interests therein, the Selling Stockholders may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of the securities in the course of hedging the positions they assume. The Selling Stockholders may also sell securities short and deliver these securities to close out their short positions, or loan or pledge the securities to broker-dealers that in turn may sell these securities. The Selling Stockholders may also enter into option or other transactions with broker-dealers or other financial institutions or create one or more derivative securities that require the delivery to such broker-dealer or other financial institution of securities offered by this prospectus, which securities such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction). The Selling Stockholders also may transfer the securities in other circumstances, in which case the transferees, pledgees, donees or other successors in interest will be the selling beneficial owners for purposes of this prospectus.

Annex A-1

The Selling Stockholders and any broker-dealers or agents that are involved in selling the securities may be deemed to be “underwriters” within the meaning of the Securities Act in connection with such sales (it being understood that the Selling Stockholders shall not be deemed to be underwriters solely as a result of their participation in this offering). In such event, any commissions received by such broker-dealers or agents and any profit on the resale of the securities purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. Each Selling Stockholder has informed us that it does not have any written or oral agreement or understanding, directly or indirectly, with any person to distribute the securities.

We are required to pay certain fees and expenses incurred by us incident to the registration of the securities. We have agreed to indemnify the Selling Stockholders against certain losses, claims, damages and liabilities, including liabilities under the Securities Act.

We agreed to keep this prospectus effective until the earlier of the date that the securities (i) have been sold, pursuant to this prospectus or pursuant to Rule 144, or (ii) the date on which the securities may be resold by the Selling Stockholders without registration and without regard to any volume or manner-of-sale limitations by reason of Rule 144, and without the requirement for us to be in compliance with the current public information under Rule 144 under the Securities Act or any other rule of similar effect. The resale securities will be sold only through registered or licensed brokers or dealers if required under applicable state securities laws. In addition, in certain states, the resale securities covered hereby may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

Under applicable rules and regulations under the Exchange Act, any person engaged in the distribution of the resale securities may not simultaneously engage in market making activities with respect to the common stock for the applicable restricted period, as defined in Regulation M, prior to the commencement of the distribution. In addition, the Selling Stockholders will be subject to applicable provisions of the Exchange Act and the rules and regulations thereunder, including Regulation M, which may limit the timing of purchases and sales of the common stock by the Selling Stockholders or any other person. We will make copies of this prospectus available to the Selling Stockholders and have informed them of the need to deliver a copy of this prospectus to each purchaser at or prior to the time of the sale (including by compliance with Rule 172 under the Securities Act).

Annex A-2

Annex C

SELLING STOCKHOLDERS

For additional information regarding the issuances of those shares of common stock being registered for resale in this registration statement, see “Private Placement of Shares of Common Stock” and “Business Combination of Korro Bio, Inc. and Frequency Therapeutics, Inc.” above. We are registering the shares of common stock in order to permit the selling stockholders to offer the shares for resale from time to time.

The table below lists the selling stockholders and other information regarding the beneficial ownership of the shares of common stock by each of the selling stockholders. The second column lists the number of shares of common stock beneficially owned by each selling stockholder, based on its ownership of the shares of common stock, as of                     , 2023.

The third column lists the shares of common stock being offered by this prospectus by the selling stockholders.

The fourth column reflects the number of shares of common stock beneficially owned by each selling stockholder, assuming the sale of all of the shares offered by the selling stockholders pursuant to this prospectus.

The selling stockholders may sell all, some or none of their shares in this offering. See “Plan of Distribution.”

Annex C-1

Annex C

Selling Stockholder Notice and Questionnaire

The undersigned owner of Registrable Securities (as such term is defined in the Registration Rights Agreement) of Korro Bio, Inc., a Delaware corporation (the “Company”), understands that the Company has filed or intends to file with the Securities and Exchange Commission (the “Commission”) a Registration Statement for the registration and resale under Rule 415 of the Securities Act of 1933, as amended (the “Securities Act”), of the Registrable Securities, in accordance with the terms of the Registration Rights Agreement dated as of July 14, 2023 to which the Company and the undersigned are parties (the “Registration Rights Agreement”). A copy of the Registration Rights Agreement is available from the Company upon request at the address set forth below. All capitalized terms not otherwise defined herein shall have the meanings ascribed thereto in the Registration Rights Agreement.

Certain legal consequences arise from being named as a selling stockholder in the Registration Statement and the related prospectus. Accordingly, holders and beneficial owners of Registrable Securities are advised to consult their own securities law counsel regarding the consequences of being named or not being named as a selling stockholder in the Registration Statement and the related prospectus.

NOTICE

The undersigned beneficial owner (the “Selling Stockholder”) of Registrable Securities hereby elects to include the Registrable Securities owned by it in the Registration Statement.

The undersigned hereby provides the following information to the Company and represents and warrants that such information is accurate as of the date hereof:

QUESTIONNAIRE

Yes  ☐    No  ☐

Annex C-1

Yes  ☐    No  ☐

Yes  ☐    No  ☐

Yes  ☐    No  ☐

Except as set forth below in this Item 4, the undersigned is not the beneficial or registered owner of any securities of the Company other than the securities issuable pursuant to the Purchase Agreement.

Except as set forth below, neither the undersigned has not held any position or office or had any other material relationship with the Company (or its predecessors or affiliates) during the past three years.

State any exceptions here:

The undersigned agrees to promptly notify the Company of any material inaccuracies or changes in the information provided herein that may occur subsequent to the date hereof at any time while the Registration Statement remains effective; provided, that the undersigned shall not be required to notify the Company of any changes to the number of securities held or owned by the undersigned or its affiliates.

By signing below, the undersigned consents to the disclosure of the information contained herein in its answers to Items 1 through 5 and the inclusion of such information in the Registration Statement and the related prospectus and any amendments or supplements thereto to the extent (but only to the extent) required by Regulation S-K. The undersigned understands that such information will be relied upon by the Company in connection with the preparation or amendment of the Registration Statement and the related prospectus and any amendments or supplements thereto.

IN WITNESS WHEREOF the undersigned, by authority duly given, has caused this Notice and Questionnaire to be executed and delivered either in person or by its duly authorized agent.

PLEASE FAX A COPY (OR EMAIL A .PDF COPY) OF THE COMPLETED AND EXECUTED NOTICE AND QUESTIONNAIRE TO:

Exhibit 10.3

LOCK-UP AGREEMENT

Ladies and Gentlemen:

The undersigned signatory of this lock-up agreement (this “Lock-Up Agreement”) understands that Frequency Therapeutics, Inc., a Delaware corporation (“Frequency”), has entered into an Agreement and Plan of Merger, dated as of July 14, 2023 (as the same may be amended from time to time, the “Merger Agreement”) with Frequency Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Frequency, and Korro Bio, Inc., a Delaware corporation (the “Company”). Capitalized terms used but not otherwise defined herein shall have the respective meanings ascribed to such terms in the Merger Agreement.

As a condition and inducement to each of the parties to enter into the Merger Agreement, and for other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the undersigned hereby irrevocably agrees that, subject to the exceptions set forth herein, without the prior written consent of Frequency and, solely prior to the Closing, the Company, the undersigned will not, during the period commencing upon the Closing and ending on the date that is 180 days after the Closing Date (the “Restricted Period”):

The restrictions and obligations contemplated by this Lock-Up Agreement shall not apply to:

provided that, in the case of any transfer or distribution pursuant to this clause (a), such transfer is not for value and each donee, heir, beneficiary or other transferee or distributee shall sign and deliver to Frequency a lock-up agreement in the form of this Lock-Up Agreement with respect to the shares of Frequency Common Stock or such other securities that have been so transferred or distributed;

(b) the exercise of an option to purchase Frequency Common Stock (including a net or cashless exercise of an option to purchase Frequency Common Stock), and any related transfer of shares of Frequency Common Stock to Frequency or sale of Frequency Common Stock in the open market, in each case, for the purpose of paying the exercise price of such options or for paying taxes (including estimated taxes) during the Restricted Period due as a result of the exercise of such options; provided that, for the avoidance of doubt, the underlying shares of Frequency Common Stock held by the undersigned following such exercise and any such open market sales shall continue to be subject to the restrictions on transfer set forth in this Lock-Up Agreement;

(c) the disposition (including a forfeiture or repurchase) to Frequency of any shares of restricted stock granted pursuant to the terms of any employee benefit plan or restricted stock purchase agreement;

2

(d) transfers to Frequency, or sales of Frequency Common Stock in the open market, in connection with the vesting of any restricted stock unit or settlement of any other equity award that represents the right to receive shares of Frequency Common Stock settled in Frequency Common Stock, in each case, to pay any tax withholding obligations due during the Restricted Period; provided that, for the avoidance of doubt, the underlying shares of Frequency Common Stock held by the undersigned following such exercise and any such open market sales shall continue to be subject to the restrictions on transfer set forth in this Lock-Up Agreement;

(f) the establishment of a trading plan pursuant to Rule 10b5-1 under the Exchange Act (a “10b5-1 Plan”) for the transfer of Frequency Common Stock; provided that such plan does not provide for any transfers of Frequency Common Stock during the Restricted Period, or the sale of Frequency Common Stock pursuant to a 10b5-1 Plan existing as of the date of the Merger Agreement (which, for clarity, shall not be amended during the Restricted Period, but may be terminated during the Restricted Period);

(f) transfers, sales, dispositions, or the entering into of transactions (including, without limitation, any swap, hedge or similar agreement) by the undersigned of or relating to shares of capital stock or other securities of Frequency purchased or acquired by the undersigned on the open market, in a public offering by Frequency, or that otherwise do not involve or relate to shares of Frequency Common Stock issued pursuant to the Merger Agreement in respect of shares of the Company;

(g) pursuant to a bona-fide third party tender offer, merger, consolidation or other similar transaction made to all holders of Frequency’s capital stock involving a change of control of Frequency, provided that in the event that such tender offer, merger, consolidation or other such transaction is not completed, the Undersigned’s Shares shall remain subject to the restrictions contained in this Lock-Up Agreement;

(h) pursuant to an order of a court or regulatory agency; or

(i) transfers, sales, dispositions, or the entering into of transaction (including, without limitation, any swap, hedge, or similar agreement), by the undersigned relating to shares of Frequency Common Stock issued pursuant to the Merger Agreement in respect of shares of the Company, if any, purchased from the Company pursuant to the Concurrent Financing (as defined in the Merger Agreement) or issued in exchange for, or on conversion or exercise of, any securities issued as part of the Concurrent Financing.

And provided, further, that, with respect to each of (a), (b), (c), (d) and (e) above, no filing by any party (including any donor, donee, transferor, transferee, distributor or distributee) under Section 16 of the Exchange Act or other public announcement shall be made voluntarily in connection with such transfer or disposition during the Restricted Period; provided that (i) any filing under Section 16 of the Exchange Act made during the Restricted Period shall clearly indicate in the footnotes thereto that such filing relates to the circumstances described in (a), (b), (c), (d) or (e), as applicable and (ii) the foregoing shall not prevent the undersigned from filing a Form 13F, Schedule 13G or Schedule 13D, or any amendment thereto, or from disclosing its holdings in Frequency as required by law or regulation or its internal disclosure policies in the ordinary course of business.

Any attempted transfer in violation of this Lock-Up Agreement will be of no effect and null and void, regardless of whether the purported transferee has any actual or constructive knowledge of the transfer restrictions set forth in this Lock-Up Agreement, and will not be recorded on the share register of Frequency. In furtherance of the foregoing, the undersigned agrees that Frequency and any duly appointed

3

transfer agent for the registration or transfer of the securities described herein are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this Lock-Up Agreement. Frequency may cause the legend set forth below, or a legend substantially equivalent thereto, to be placed upon any certificate(s) or other documents, ledgers or instruments evidencing the undersigned’s ownership of Frequency Common Stock:

THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO AND MAY ONLY BE TRANSFERRED IN COMPLIANCE WITH A LOCK-UP AGREEMENT, A COPY OF WHICH IS ON FILE AT THE PRINCIPAL OFFICE OF THE COMPANY.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Lock-Up Agreement. All authority herein conferred or agreed to be conferred and any obligations of the undersigned shall be binding upon the successors, assigns, heirs or personal representatives of the undersigned.

The undersigned understands that if the Merger Agreement is terminated for any reason, the undersigned shall be released from all obligations under this Lock-Up Agreement. The undersigned understands that Frequency and the Company are proceeding with the Contemplated Transactions in reliance upon this Lock-Up Agreement. Notwithstanding anything to the contrary contained herein, this letter agreement will automatically terminate and the undersigned shall be released from all obligations under this letter agreement upon the earliest to occur, if any, of (i) the Company advising the undersigned in writing that it has determined not to proceed with the Contemplated Transactions or (ii) the Merger Agreement being terminated.

Any and all remedies herein expressly conferred upon Frequency or the Company will be deemed cumulative with and not exclusive of any other remedy conferred hereby, or by Law or equity, and the exercise by Frequency or the Company of any one remedy will not preclude the exercise of any other remedy. The undersigned agrees that irreparable damage could occur to Frequency and/or the Company in the event that any provision of this Lock-Up Agreement were not performed in accordance with its specific terms or were otherwise breached. It is accordingly agreed that Frequency and the Company shall be entitled to seek an injunction or injunctions to prevent breaches of this Lock-Up Agreement and to enforce specifically the terms and provisions hereof in any court of the United States or any state having jurisdiction, this being in addition to any other remedy to which Frequency or the Company is entitled at Law or in equity, and the undersigned waives any bond, surety or other security that might be required of Frequency or the Company with respect thereto.

In the event that any holder of Frequency’s securities that are subject to a substantially similar agreement entered into by such holder, other than the undersigned, is permitted by Frequency (or prior to the Closing, the Company), including through any written consent granted under subparagraph a(ii)(E) above, to sell or otherwise transfer or dispose of shares of Frequency Common Stock for value other than as permitted by this or a substantially similar agreement entered into by such holder or is granted an early release from the restrictions described herein during the Restricted Period, the same percentage of shares of the Undersigned’s Shares shall be immediately and fully released from any remaining restrictions set forth herein (the “Pro-Rata Release”); provided, however, that such Pro-Rata Release shall not be applied unless and until permission or early release has been granted by Frequency, and solely prior to the Closing, the Company, to an equity holder or equity holders to sell or otherwise transfer or dispose of all or a portion of such equity holder’s shares of Frequency Common Stock that, when combined with all such other such permissions and early releases, represent an aggregate amount in excess of 1% of the number of shares of Frequency Common Stock originally subject to a substantially similar agreements. Frequency shall notify the undersigned of any Pro Rata Release of its shares on the same day that any permission that triggers the Pro Rata Release is granted.

4

Upon the release of any of the Undersigned’s Shares from this Lock-Up Agreement, Frequency will cooperate with the undersigned to facilitate the timely preparation and delivery of certificates representing the Undersigned’s Shares without the restrictive legend above or the withdrawal of any stop transfer instructions.

This Lock-Up Agreement and any claim, controversy or dispute arising under or related to this Lock-Up Agreement shall be governed by and construed in accordance with the Laws of the State of Delaware, without regard to the conflict of Laws principles thereof.

This Lock-Up Agreement may be executed in several counterparts, each of which shall be deemed an original and all of which shall constitute one and the same instrument. The exchange of a fully executed Lock-Up Agreement (in counterparts or otherwise) by Frequency, the Company and the undersigned by facsimile, electronic mail (including any electronic signature covered by the U.S. federal ESIGN Act of 2000, Uniform Electronic Transactions Act, the Electronic Signatures and Records Act or other applicable law, e.g., www.docusign.com) or electronic transmission in .pdf format shall be sufficient to bind such parties to the terms and conditions of this Lock-Up Agreement.

(Signature Page Follows)

5

[Signature Page to Lock-up Agreement]

Exhibit 10.4

CONTINGENT VALUE RIGHTS AGREEMENT

BETWEEN

FREQUENCY THERAPEUTICS, INC.

and

COMPUTERSHARE TRUST COMPANY, N.A.

and COMPUTERSHARE INC., collectively, as Rights Agent

Dated as of November 3, 2023

TABLE OF CONTENTS

FORM OF

CONTINGENT VALUE RIGHTS AGREEMENT

THIS CONTINGENT VALUE RIGHTS AGREEMENT (this “Agreement”), dated as of November 3, 2023, is entered into by and between Frequency Therapeutics, Inc., a Delaware corporation (“Frequency”), and Computershare Inc., a Delaware corporation (“Computershare”), and its affiliate, Computershare Trust Company, N.A., a national banking association, collectively, as initial Rights Agent (as defined herein).

PREAMBLE

WHEREAS, Frequency, Frequency Merger Sub, Inc., a Delaware corporation and wholly-owned subsidiary of Frequency (“Merger Sub”), and Korro Bio, Inc., a Delaware corporation (the “Company”), have entered into an Agreement and Plan of Merger, dated as of July 14, 2023 (the “Merger Agreement”), pursuant to which Merger Sub will merge with and into the Company (the “Merger”), with the Company surviving the Merger as a wholly-owned subsidiary of Frequency (the “Surviving Corporation”);

WHEREAS, in connection with the Merger Agreement, Frequency has agreed to provide to the Holders (as defined herein) contingent value rights as hereinafter described;

WHEREAS, the parties have done all things necessary to make the contingent value rights, when issued pursuant to this Agreement, the valid obligations of Frequency and to make this Agreement a valid and binding agreement of Frequency, in accordance with its terms; and

NOW, THEREFORE, in consideration of the premises and the consummation of the transactions referred to above, it is mutually covenanted and agreed, for the proportionate benefit of all Holders, as follows:

ARTICLE 1

DEFINITIONS

Section 1.1 Definitions.

Capitalized terms used but not otherwise defined herein have the meanings ascribed thereto in the Merger Agreement. The following terms have the meanings ascribed to them as follows:

“Business Day” means any day other than a day on which banks in the State of New York are authorized or obligated to be closed.

“Closing Date” means the date on which the Closing actually takes place.

“CVR” means a contingent contractual right of Holders to receive CVR Payments under this Agreement.

“CVR Payment” means the CVR Proceeds for a given payment.

1

“CVR Period” means the period beginning immediately following the Effective Time and ending on the tenth anniversary of the Closing Date.

“CVR Proceeds” means, upon the consummation of any MS Asset Disposition following the Closing Date and prior to expiration of the Disposition Period or, if applicable, the fiscal quarter during the CVR Period in which the proceeds of any MS Asset Disposition are received, the amount of Gross Proceeds actually received by Frequency or any of its Subsidiaries upon such consummation or during the applicable fiscal quarter, less the applicable reasonably documented Permitted Deductions with respect to such Gross Proceeds, in each case as calculated in accordance with GAAP consistently applied.

“Disposition Period” means the period beginning on the execution date of the Merger Agreement and ending on the one year anniversary of the Closing Date.

“Effective Time” means the time at which the Merger shall become effective at the time of the filing of the Certificate of Merger and the acceptance by the Secretary of State of the State of Delaware, or at such later time as may be specified in such Certificate of Merger with the consent of Frequency and Korro.

“Gross Proceeds” means, without duplication, all cash consideration that is paid to, or is received by, Frequency or any of its Subsidiaries during the CVR Period in consideration for an MS Asset Disposition.

“Holder” means, at the relevant time, a Person in whose name CVRs are registered in the CVR Register.

“Majority of Holders” means, at any time, the registered Holder or Holders of more than 50% of the total number of CVRs registered at such time, as set forth on the CVR Register.

“MS Assets” means the assets, rights and interests held by or on behalf of Frequency or any of its Subsidiaries as of the execution date of the Merger Agreement relating to Frequency’s MS remyelination program, including but not limited to any such intellectual property rights and data.

“MS Asset Disposition” means the sale, transfer, license, assignment or other divestiture, disposition or commercialization of any MS Assets (including any such sale or disposition of equity securities in any Subsidiary that was established by Frequency during the Disposition Period solely to hold any right, title or interest in or to all or any MS Assets) in a transaction or series of transactions, in each case entered into during the Disposition Period.

“Officer’s Certificate” means a certificate signed by the chief executive officer or the chief financial officer of Frequency, in their respective official capacities.

2

“Permitted Deductions” means the following costs or expenses, without duplication:

3

“Permitted Transfer” means a Transfer of one or more CVRs (i) upon death of a Holder by will or intestacy; (ii) by instrument to an inter vivos or testamentary trust in which the CVRs are to be passed to beneficiaries upon the death of the trustee; (iii) made pursuant to a court order of a court of competent jurisdiction (such as in connection with divorce, bankruptcy or liquidation); (iv) made by operation of law (including a consolidation or merger) or without consideration in connection with the dissolution, liquidation or termination of any corporation, limited liability company, partnership or other entity; (v) in the case of CVRs payable to a nominee, from a nominee to a beneficial owner (and, if applicable, through an intermediary) or from such nominee to another nominee for the same beneficial owner, in each case as permitted by The Depository Trust Company; (vi) to Frequency or its Subsidiaries; or (vii) as provided in Section 2.6.

“Person” means any individual, partnership, joint venture, limited liability company, firm, corporation, unincorporated association or organization, trust or other entity, and shall include any successor (by merger or otherwise) of any such Person.

“Record Date” means the close of business on the last Business Day prior to the day on which the Effective Time occurs.

“Rights Agent” means the Rights Agent named in the first paragraph of this Agreement, until a successor Rights Agent shall have been appointed pursuant to Article 3 of this Agreement, and thereafter “Rights Agent” will mean such successor Rights Agent.

“Transfer” means transfer, pledge, hypothecation, encumbrance, assignment or other disposition (whether by sale, merger, consolidation, liquidation, dissolution, dividend, distribution or otherwise), the offer to make such a transfer or other disposition, and each contract, arrangement or understanding, whether or not in writing, to effect any of the foregoing.

ARTICLE 2

CONTINGENT VALUE RIGHTS

Section 2.1 Holders of CVRs; Appointment of Rights Agent.

Section 2.2 Non-transferable.

A Holder may not at any time Transfer CVRs, other than pursuant to a Permitted Transfer. Any attempted Transfer that is not a Permitted Transfer, in whole or in part, will be void ab initio and of no effect. The CVRs will not be listed on any quotation system or traded on any securities exchange.

Section 2.3 No Certificate; Registration; Registration of Transfer; Change of Address.

4

Section 2.4 Payment Procedures.

5

6

Section 2.5 No Voting, Dividends or Interest; No Equity or Ownership Interest.

Section 2.6 Ability to Abandon CVR.

A Holder may at any time, at such Holder’s option, abandon all of such Holder’s remaining rights represented by CVRs by transferring such CVR to Frequency or a person nominated in writing by Frequency (with written notice thereof from Frequency to the Rights Agent) without consideration or compensation therefor, and such rights will be cancelled, with the Rights Agent being promptly notified in writing by Frequency of such transfer and cancellation. Nothing in this Agreement is intended to prohibit Frequency or its Subsidiaries from offering to acquire or acquiring CVRs, in private transactions or otherwise, for consideration in its sole discretion.

7

ARTICLE 3

THE RIGHTS AGENT

Section 3.1 Certain Duties and Responsibilities.

Section 3.2 Certain Rights of Rights Agent.

8

9

10

Section 3.3 Resignation and Removal; Appointment of Successor.

11

Section 3.4 Acceptance of Appointment by Successor.

Every successor Rights Agent appointed hereunder will, at or prior to such appointment, execute, acknowledge and deliver to Frequency and to the resigning or removed Rights Agent an instrument accepting such appointment and a counterpart of this Agreement, and such successor Rights Agent, without any further act, deed or conveyance, will become vested with all the rights, powers, trusts and duties of the Rights Agent; provided that upon the request of Frequency or the successor Rights Agent, such resigning or removed Rights Agent will execute and deliver an instrument transferring to such successor Rights Agent all the rights, powers and trusts of such resigning or removed Rights Agent.

ARTICLE 4

COVENANTS

Section 4.1 List of Holders.

Frequency will furnish or cause to be furnished to the Rights Agent, in such form as Frequency receives from Frequency’s transfer agent (or other agent performing similar services for Frequency), the names and addresses of the Holders within fifteen (15) Business Days following the Closing Date.

Section 4.2 CVR Committee; Efforts.

12

13

Section 4.3 Prohibited Actions.

Unless approved by the Special Committee (or the Frequency Board if the Special Committee no longer exists), Frequency shall not grant any lien, security interest, pledge or similar interest in any MS Assets (other than liens or security interests generally granted with respect to all assets of Frequency, and not specific to the MS Assets, and which do not prohibit the ability of Frequency to complete an MS Asset Disposition and, in connection therewith, to deliver title to the MS Assets to the purchaser thereof, free and clear of such liens and security interests) or any CVR Proceeds.

ARTICLE 5

AMENDMENTS

Section 5.1 Amendments Without Consent of Holders or Rights Agent.

14

Section 5.2 Amendments with Consent of Holders.

15

Section 5.3 Effect of Amendments.

Upon the execution of any amendment under this Article 5, this Agreement will be modified in accordance therewith, such amendment will form a part of this Agreement for all purposes and every Holder will be bound thereby. Upon the delivery of a certificate from an appropriate officer of Frequency which states that the proposed supplement or amendment is in compliance with the terms of this Article 5, the Rights Agent shall execute such supplement or amendment. Notwithstanding anything in this Agreement to the contrary, the Rights Agent shall not be required to execute any supplement or amendment to this Agreement that it has determined would adversely affect its own rights, duties, obligations or immunities under this Agreement. No supplement or amendment to this Agreement shall be effective unless duly executed by the Rights Agent.

ARTICLE 6

CONSOLIDATION, MERGER, SALE OR CONVEYANCE

Section 6.1 Frequency May Not Consolidate, Etc.

During the CVR Period, Frequency shall not consolidate with or merge into any other Person or convey, transfer or lease all or substantially all of its properties and assets to any Person, unless:

Section 6.2 Successor Substituted.

Upon any consolidation of or merger by Frequency with or into any other Person, or any conveyance, transfer or lease of the properties and assets substantially as an entirety to any Person in accordance with Section 6.1, the Surviving Person shall succeed to, and be substituted for, and may exercise every right and power of, and shall assume all of the obligations of Frequency under this Agreement with the same effect as if the Surviving Person had been named as Frequency herein.

ARTICLE 7

MISCELLANEOUS

Section 7.1 Notices to Rights Agent and to Frequency.

All notices, requests and other communications (each, a “Notice”) to any party hereunder shall be in writing. Such Notice shall be deemed given (a) on the date of delivery, if delivered in person, by Fedex or other internationally recognized overnight courier service or, (except with respect to any Person other than the Rights Agent), by e-mail (upon confirmation of receipt) prior to 5:00 p.m. in the time zone of the receiving party or on the next Business Day, if delivered after 5:00 p.m. in the time zone of the receiving party or (b) on the first Business Day following the date

16

of dispatch, if delivered by FedEx or by other internationally recognized overnight courier service (upon proof of delivery), addressed as follows:

if to the Rights Agent, to:

Computershare Trust Company, N.A.

150 Royall Street

Canton, MA 02021

if to Frequency, to:

Frequency Therapeutics

75 Hayden Ave

Lexington, MA 02421

Attention: Shelby Walker

Email: legal@korrobio.com

with a copy, which shall not constitute notice, to:

Goodwin Procter LLP

100 Northern Avenue

Boston, Massachusetts 02210

Attention: Kingsley L. Taft, Andrew H. Goodman

Email: ktaft@goodwinlaw.com, agoodman@goodwinlaw.com

or to such other address or facsimile number as such party may hereafter specify for the purpose by notice to the other parties hereto.

Section 7.2 Notice to Holders.

All Notices required to be given to the Holders will be given (unless otherwise herein expressly provided) in writing and mailed, first-class postage prepaid, to each Holder at such Holder’s address as set forth in the CVR Register, not later than the latest date, and not earlier than the earliest date, prescribed for the sending of such Notice, if any, and will be deemed given on the date of mailing. In any case where notice to the Holders is given by mail, neither the failure to mail such Notice, nor any defect in any Notice so mailed, to any particular Holder will affect the sufficiency of such Notice with respect to other Holders.

Section 7.3 Entire Agreement.

As between Frequency and the Rights Agent, this Agreement constitutes the entire agreement between the parties with respect to the subject matter of this Agreement, notwithstanding the reference to any other agreement herein, and supersedes all prior agreements and understandings, both written and oral, among or between any of the parties with respect to the subject matter of this Agreement.

17

Section 7.4 Merger or Consolidation or Change of Name of Rights Agent.

Any Person into which the Rights Agent or any successor Rights Agent may be merged or with which it may be consolidated, or Person resulting from any merger or consolidation to which the Rights Agent or any successor Rights Agent shall be a party, or any Person succeeding to the stock transfer or other shareholder services business of the Rights Agent or any successor Rights Agent, shall be the successor to the Rights Agent under this Agreement without the execution or filing of any paper or any further act on the part of any of the parties hereto, provided that such Person would be eligible for appointment as a successor Rights Agent under the provisions of Section 3.3. The purchase of all or substantially all of the Rights Agent’s assets employed in the performance of transfer agent activities shall be deemed a merger or consolidation for purposes of this Section 7.4.

Section 7.5 Successors and Assigns.

This Agreement will be binding upon, and will be enforceable by and inure solely to the benefit of, the Holders, Frequency and the Rights Agent and their respective successors and assigns. Except for assignments pursuant to Section 7.4, the Rights Agent may not assign this Agreement without Frequency’s prior written consent. Subject to Section 5.1(a)(ii) and Article 6 hereof, Frequency may assign, in its sole discretion and without the consent of any other party, any or all of its rights, interests and obligations hereunder to one or more of its Affiliates or to any Person with whom Frequency is merged or consolidated, or any entity resulting from any merger or consolidation to which Frequency shall be a party (each, an “Assignee”); provided, however, that in connection with any assignment to an Assignee, Frequency shall agree to remain liable for the performance by Frequency of its obligations hereunder (to the extent Frequency exists following such assignment). Frequency or an Assignee may not otherwise assign this Agreement without the prior consent of the Majority of Holders. Any attempted assignment of this Agreement in violation of this Section 7.5 will be void ab initio and of no effect.

Section 7.6 Benefits of Agreement; Action by Majority of Holders.

Nothing in this Agreement, express or implied, will give to any Person (other than Frequency, the Rights Agent, the Holders and their respective permitted successors and assigns hereunder) any benefit or any legal or equitable right, remedy or claim under this Agreement or under any covenant or provision herein contained, all such covenants and provisions being for the sole benefit of Frequency, the Rights Agent, the Holders and their permitted successors and assigns. The Holders will have no rights hereunder except as are expressly set forth herein. Except for the rights of the Rights Agent set forth herein, the Majority of Holders will have the sole right, on behalf of all Holders, by virtue of or under any provision of this Agreement, to institute any action or proceeding at law or in equity with respect to this Agreement, and no individual Holder or other group of Holders will be entitled to exercise such rights.

Section 7.7 Governing Law.

This Agreement and the CVRs will be governed by, and construed in accordance with, the laws of the State of Delaware without regard to the conflicts of law rules of such state.

18

Section 7.8 Jurisdiction.

In any action or proceeding between any of the parties hereto arising out of or relating to this Agreement or any of the transactions contemplated hereby, each of the parties hereto: (a) irrevocably and unconditionally consents and submits to the exclusive jurisdiction and venue of the Chancery Court of the State of Delaware, County of New Castle, or, if under applicable Law exclusive jurisdiction is vested in the Federal courts, the United States District Court for the District of Delaware (and appellate courts thereof); (b) agrees that all claims in respect of such action or proceeding shall be heard and determined exclusively in accordance with clause (a) of this Section 7.8; (c) waives any objection to laying venue in any such action or proceeding in such courts; (d) waives any objection that such courts are an inconvenient forum or do not have jurisdiction over any Party; and (e) agrees that service of process upon such Party in any such action or proceeding shall be effective if notice is given in accordance with Section 7.1 or Section 7.2 of this Agreement.

Section 7.9 WAIVER OF JURY TRIAL.

EACH OF THE PARTIES HERETO (AND BY ACCEPTING THE CVR’ S, THE HOLDERS) HEREBY IRREVOCABLY WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATED TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY. EACH PARTY CERTIFIES AND ACKNOWLEDGES THAT (I) NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER, (II) EACH PARTY UNDERSTANDS AND HAS CONSIDERED THE IMPLICATION OF THIS WAIVER, (III) EACH PARTY MAKES THIS WAIVER VOLUNTARILY, AND (IV) EACH PARTY HAS BEEN INDUCED TO ENTER INTO THIS AGREEMENT BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS SECTION 7.9.

Section 7.10 Severability Clause.

In the event that any provision of this Agreement, or the application of any such provision to any Person or set of circumstances, is for any reason determined to be invalid, unlawful, void or unenforceable to any extent, the remainder of this Agreement, and the application of such provision to Persons or circumstances other than those as to which it is determined to be invalid, unlawful, void or unenforceable, will not be impaired or otherwise affected and will continue to be valid and enforceable to the fullest extent permitted by applicable Law. Upon such a determination, the parties hereto will negotiate in good faith to modify this Agreement so as to effect the original intent of the parties as closely as possible in a mutually acceptable manner in order that the transactions contemplated hereby be consummated as originally contemplated to the fullest extent possible; provided, however, that if an excluded provision shall affect the rights, immunities, liabilities, duties or obligations of the Rights Agent, the Rights Agent shall be entitled to resign immediately upon written notice to Frequency.

19

Section 7.11 Counterparts; Effectiveness.

This Agreement may be signed in any number of counterparts, each of which will be deemed an original, with the same effect as if the signatures thereto and hereto were upon the same instrument. This Agreement or any counterpart may be executed and delivered by facsimile copies or delivered by electronic communications by portable document format (.pdf), each of which shall be deemed an original. This Agreement will become effective when each party hereto will have received a counterpart hereof signed by the other party hereto. Until and unless each party has received a counterpart hereof signed by the other party hereto, this Agreement will have no effect and no party will have any right or obligation hereunder (whether by virtue of any oral or written agreement or any other communication).

Section 7.12 Termination.

This Agreement will automatically terminate and be of no further force or effect and, except as provided in Section 3.2, the parties hereto will have no further liability hereunder, and the CVRs will expire without any consideration or compensation therefor, upon the expiration of the CVR Period. The termination of this Agreement will not affect or limit the right of Holders to receive the CVR Payments under Section 2.4 to the extent earned prior to the termination of this Agreement, and the provisions applicable thereto will survive the expiration or termination of this Agreement.

Section 7.13 Force Majeure.

Notwithstanding anything to the contrary contained herein, none of the Rights Agent, Frequency or any of its Subsidiaries (except as it relates to the obligations of the Company under Article 3) will be liable for any delays or failures in performance resulting from acts beyond its reasonable control including acts of God, pandemics (including COVID-19), terrorist acts, shortage of supply, breakdowns or malfunctions, interruptions or malfunctions of computer facilities, or loss of data due to power failures or mechanical difficulties with information storage or retrieval systems, labor difficulties, war or civil unrest.

Section 7.14 Construction.

20

[Remainder of page intentionally left blank]

21

IN WITNESS WHEREOF, each of the parties has caused this Agreement to be executed as of the day and year first above written.

COMPUTERSHARE TRUST COMPANY, N.A. and

COMPUTERSHARE INC., collectively as Rights Agent

22

Exhibit 10.6

KORRO BIO, INC.

AMENDED AND RESTATED

FORM OF OFFICER INDEMNIFICATION AGREEMENT

This Indemnification Agreement (“Agreement”) is made as of ________________ by and between Korro Bio, Inc., a Delaware corporation (the “Company”), and ____________ (“Indemnitee”).

RECITALS

WHEREAS, the Company desires to attract and retain the services of highly qualified individuals, such as Indemnitee, to serve the Company;

WHEREAS, in order to induce Indemnitee to [provide or continue to provide] services to the Company, the Company wishes to provide for the indemnification of, and advancement of expenses to, Indemnitee to the maximum extent permitted by law;

WHEREAS, the Certificate of Incorporation (the “Charter”) and the Bylaws (the “Bylaws”) of the Company require indemnification of the officers and directors of the Company, and Indemnitee may also be entitled to indemnification pursuant to the General Corporation Law of the State of Delaware (the “DGCL”);

WHEREAS, the Charter, the Bylaws and the DGCL expressly provide that the indemnification provisions set forth therein are not exclusive, and thereby contemplate that contracts may be entered into between the Company and members of the board of directors, officers and other persons with respect to indemnification;

WHEREAS, the Board of Directors of the Company (the “Board”) has determined that the increased difficulty in attracting and retaining highly qualified persons such as Indemnitee is detrimental to the best interests of the Company’s stockholders;

WHEREAS, it is reasonable and prudent for the Company contractually to obligate itself to indemnify, and to advance expenses on behalf of, such persons to the fullest extent permitted by applicable law, regardless of any amendment or revocation of the Charter or the Bylaws, so that they will serve or continue to serve the Company free from undue concern that they will not be so indemnified; and

WHEREAS, this Agreement is a supplement to and in furtherance of the indemnification provided in the Charter, the Bylaws and any resolutions adopted pursuant thereto, and shall not be deemed a substitute therefor, nor to diminish or abrogate any rights of Indemnitee thereunder.

NOW, THEREFORE, in consideration of the premises and the covenants contained herein, the Company and Indemnitee do hereby covenant and agree as follows:

Section 1. Services to the Company. Indemnitee agrees to serve as an officer of the Company. Indemnitee may at any time and for any reason resign from such position (subject to any other contractual obligation or any obligation imposed by law), in which event the Company shall have no obligation under this Agreement to continue Indemnitee in such position. This Agreement shall not be deemed an employment contract between the Company (or any of its subsidiaries or any Enterprise) and Indemnitee.

Section 2. Definitions.

As used in this Agreement:

(a) “Affiliate” and “Associate” shall have the respective meanings ascribed to such terms in Rule 12b-2 of the General Rules and Regulations under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), as in effect on the date of this Agreement; provided, however, that no Person who is a director or officer of the Company shall be deemed an Affiliate or an Associate of any other director or officer of the Company solely as a result of his or her position as director or officer of the Company.

(b) A Person shall be deemed the “Beneficial Owner” of, and shall be deemed to “Beneficially Own” and have “Beneficial Ownership” of, any securities:

(i) which such Person or any of such Person’s Affiliates or Associates, directly or indirectly, Beneficially Owns (as determined pursuant to Rule 13d-3 of the Rules under the Exchange Act, as in effect on the date of this Agreement);

(ii) which such Person or any of such Person’s Affiliates or Associates, directly or indirectly, has: (A) the legal, equitable or contractual right or obligation to acquire (whether directly or indirectly and whether exercisable immediately or only after the passage of time, compliance with regulatory requirements, satisfaction of one or more conditions (whether or not within the control of such Person) or otherwise) upon the exercise of any conversion rights, exchange rights, rights, warrants or options, or otherwise; (B) the right to vote pursuant to any agreement, arrangement or understanding (whether or not in writing); or (C) the right to dispose of pursuant to any agreement, arrangement or understanding (whether or not in writing) (other than customary arrangements with and between underwriters and selling group members with respect to a bona fide public offering of securities);

(iii) which are Beneficially Owned, directly or indirectly, by any other Person (or any Affiliate or Associate thereof) with which such Person or any of such Person’s Affiliates or Associates has any agreement, arrangement or understanding (whether or not in writing) (other than customary agreements with and between underwriters and selling group members with respect to a bona fide public offering of securities) for the purpose of acquiring, holding, voting or disposing of any securities of the Company; or

(iv) that are the subject of a derivative transaction entered into by such Person or any of such Person’s Affiliates or Associates, including, for these purposes, any derivative security acquired by such Person or any of such Person’s Affiliates or Associates that gives such Person or any of such Person’s Affiliates or Associates the economic equivalent of ownership of an amount of securities due to the fact that the value of the derivative security is explicitly determined by reference to the price or value of such securities, or that provides such Person or

2

any of such Person’s Affiliates or Associates an opportunity, directly or indirectly, to profit or to share in any profit derived from any change in the value of such securities, in any case without regard to whether (A) such derivative security conveys any voting rights in such securities to such Person or any of such Person’s Affiliates or Associates; (B) the derivative security is required to be, or capable of being, settled through delivery of such securities; or (C) such Person or any of such Person’s Affiliates or Associates may have entered into other transactions that hedge the economic effect of such derivative security.

Notwithstanding the foregoing, no Person engaged in business as an underwriter of securities shall be deemed the Beneficial Owner of any securities acquired through such Person’s participation as an underwriter in good faith in a firm commitment underwriting.

(c) A “Change in Control” shall be deemed to occur upon the earliest to occur after the date of this Agreement of any of the following events:

(i) Acquisition of Stock by Third Party. Any Person is or becomes the Beneficial Owner (as defined above), directly or indirectly, of securities of the Company representing fifty percent (50%) or more of the combined voting power of the Company’s then outstanding securities unless the change in relative Beneficial Ownership of the Company’s securities by any Person results solely from a reduction in the aggregate number of outstanding shares of securities entitled to vote generally in the election of directors, provided that a Change of Control shall be deemed to have occurred if subsequent to such reduction such Person becomes the Beneficial Owner, directly or indirectly, of any additional securities of the Company conferring upon such Person any additional voting power;

(ii) Change in Board of Directors. During any period of two (2) consecutive years (not including any period prior to the execution of this Agreement), individuals who at the beginning of such period constitute the Board, and any new director (other than a director designated by a Person who has entered into an agreement with the Company to effect a transaction described in Sections 2(c)(i), 2(c)(iii) or 2(c)(iv)) whose election by the Board or nomination for election by the Company’s stockholders was approved by a vote of at least two-thirds of the directors then still in office who either were directors at the beginning of the period or whose election or nomination for election was previously so approved, cease for any reason to constitute at least a majority of the members of the Board;

(iii) Corporate Transactions. The effective date of a merger or consolidation of the Company with any other entity, other than a merger or consolidation which would result in the voting securities of the Company outstanding immediately prior to such merger or consolidation continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving or successor entity) more than 50% of the combined voting power of the voting securities of the surviving or successor entity outstanding immediately after such merger or consolidation and with the power to elect at least a majority of the board of directors or other governing body of such surviving or successor entity;

3

(iv) Liquidation. The approval by the stockholders of the Company of a complete liquidation of the Company or an agreement for the sale, lease, exchange or other transfer by the Company, in one or a series of related transactions, of all or substantially all of the Company’s assets; and

(v) Other Events. There occurs any other event of a nature that would be required to be reported in response to Item 6(e) of Schedule 14A of Regulation 14A (or a response to any similar item on any similar schedule or form) promulgated under the Exchange Act whether or not the Company is then subject to such reporting requirement.]

(d) “Corporate Status” describes the status of a person as a current or former officer of the Company or current or former director, manager, partner, officer, employee, agent or trustee of any other Enterprise which such person is or was serving at the request of the Company.

(e) “Enforcement Expenses” shall include all reasonable attorneys’ fees, court costs, transcript costs, fees of experts, travel expenses, duplicating costs, printing and binding costs, telephone charges, postage, delivery service fees and all other out-of-pocket disbursements or expenses of the types customarily incurred in connection with an action to enforce indemnification or advancement rights, or an appeal from such action. Expenses, however, shall not include fees, salaries, wages or benefits owed to Indemnitee.

(f) “Enterprise” shall mean any corporation (other than the Company), partnership, joint venture, trust, employee benefit plan, limited liability company or other legal entity of which Indemnitee is or was serving at the request of the Company as a director, manager, partner, officer, employee, agent or trustee.

(g) “Expenses” shall include all reasonable attorneys’ fees, court costs, transcript costs, fees of experts, travel expenses, duplicating costs, printing and binding costs, telephone charges, postage, delivery service fees and all other out-of-pocket disbursements or expenses of the types customarily incurred in connection with prosecuting, defending, preparing to prosecute or defend, investigating, being or preparing to be a witness in, or otherwise participating in, a Proceeding or an appeal resulting from a Proceeding. Expenses, however, shall not include amounts paid in settlement by Indemnitee, the amount of judgments or fines against Indemnitee or fees, salaries, wages or benefits owed to Indemnitee.

(h) “Independent Counsel” means a law firm, or a partner (or, if applicable, member or shareholder) of such a law firm, that is experienced in matters of Delaware corporation law and neither presently is, nor in the past five (5) years has been, retained to represent: (i) the Company, any subsidiary of the Company, any Enterprise or Indemnitee in any matter material to any such party; or (ii) any other party to the Proceeding giving rise to a claim for indemnification hereunder. Notwithstanding the foregoing, the term “Independent Counsel” shall not include any Person who, under the applicable standards of professional conduct then prevailing, would have a conflict of interest in representing either the Company or Indemnitee in an action to determine Indemnitee’s rights under this Agreement. The Company agrees to pay the reasonable fees and expenses of the Independent Counsel referred to above and to fully indemnify such counsel against any and all expenses, claims, liabilities and damages arising out of or relating to this Agreement or its engagement pursuant hereto.

4

(i) “Person” shall mean (i) an individual, a corporation, a partnership, a limited liability company, an association, a joint stock company, a trust, a business trust, a government or political subdivision, any unincorporated organization or any other association or entity including any successor (by merger or otherwise) thereof or thereto, and (ii) a “group” as that term is used for purposes of Section 13(d)(3) of the Exchange Act.

(j) The term “Proceeding” shall include any threatened, pending or completed action, suit, arbitration, alternate dispute resolution mechanism, investigation, inquiry, administrative hearing or any other actual, threatened or completed proceeding, whether brought in the right of the Company or otherwise and whether of a civil, criminal, administrative, regulatory or investigative nature, and whether formal or informal, in which Indemnitee was, is or will be involved as a party or otherwise by reason of the fact that Indemnitee is or was an officer of the Company or is or was serving at the request of the Company as a director, manager, partner, officer, employee, agent or trustee of any Enterprise or by reason of any action taken by Indemnitee or of any action taken on his or her part while acting as an officer of the Company or while serving at the request of the Company as a director, manager, partner, officer, employee, agent or trustee of any Enterprise, in each case whether or not serving in such capacity at the time any liability or expense is incurred for which indemnification, reimbursement or advancement of expenses can be provided under this Agreement; provided, however, that the term “Proceeding” shall not include any action, suit or arbitration, or part thereof, initiated by Indemnitee to enforce Indemnitee’s rights under this Agreement as provided for in Section 12(a) of this Agreement.

Section 3. Indemnity in Third-Party Proceedings. The Company shall indemnify Indemnitee to the extent set forth in this Section 3 if Indemnitee is, or is threatened to be made, a party to or a participant in any Proceeding, other than a Proceeding by or in the right of the Company to procure a judgment in its favor. Pursuant to this Section 3, Indemnitee shall be indemnified against all Expenses, judgments, fines, penalties, excise taxes and amounts paid in settlement actually and reasonably incurred by Indemnitee or on his or her behalf in connection with such Proceeding or any claim, issue or matter therein, if Indemnitee acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the Company and, in the case of a criminal proceeding, had no reasonable cause to believe that his or her conduct was unlawful.

Section 4. Indemnity in Proceedings by or in the Right of the Company. The Company shall indemnify Indemnitee to the extent set forth in this Section 4 if Indemnitee is, or is threatened to be made, a party to or a participant in any Proceeding by or in the right of the Company to procure a judgment in its favor. Pursuant to this Section 4, Indemnitee shall be indemnified against all Expenses actually and reasonably incurred by Indemnitee or on his or her behalf in connection with such Proceeding or any claim, issue or matter therein, if Indemnitee acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the Company. No indemnification for Expenses shall be made under this Section 4 in respect of any claim, issue or matter as to which Indemnitee shall have been finally adjudged by a court to be liable to the Company, unless and only to the extent that the Delaware Court of Chancery (the “Delaware Court”) shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, Indemnitee is fairly and reasonably entitled to indemnification for such expenses as the Delaware Court shall deem proper.

5

Section 5. Indemnification for Expenses of a Party Who is Wholly or Partly Successful. Notwithstanding any other provisions of this Agreement and except as provided in Section 7, to the extent that Indemnitee is a party to or a participant in any Proceeding and is successful in such Proceeding or in defense of any claim, issue or matter therein, the Company shall indemnify Indemnitee against all Expenses actually and reasonably incurred by him or her in connection therewith. If Indemnitee is not wholly successful in such Proceeding but is successful as to one or more but less than all claims, issues or matters in such Proceeding, the Company shall indemnify Indemnitee against all Expenses actually and reasonably incurred by Indemnitee or on his or her behalf in connection with each successfully resolved claim, issue or matter. For purposes of this Section and without limitation, the termination of any claim, issue or matter in such a Proceeding by dismissal, with or without prejudice, shall be deemed to be a successful result as to such claim, issue or matter.

Section 6. Reimbursement for Expenses of a Witness or in Response to a Subpoena. Notwithstanding any other provision of this Agreement, to the extent that Indemnitee, by reason of his or her Corporate Status, (i) is a witness in any Proceeding to which Indemnitee is not a party and is not threatened to be made a party or (ii) receives a subpoena with respect to any Proceeding to which Indemnitee is not a party and is not threatened to be made a party, the Company shall reimburse Indemnitee for all Expenses actually and reasonably incurred by him or her or on his or her behalf in connection therewith.

Section 7. Exclusions. Notwithstanding any provision in this Agreement to the contrary, the Company shall not be obligated under this Agreement:

(a) to indemnify for amounts otherwise indemnifiable hereunder (or for which advancement is provided hereunder) if and to the extent that Indemnitee has otherwise actually received such amounts under any insurance policy, contract, agreement or otherwise; provided that the foregoing shall not [i] apply to any personal or umbrella liability insurance maintained by Indemnitee, [or (ii) affect the rights of Indemnitee or the Fund Indemnitors as set forth in Section 13(c)];

(b) to indemnify for an accounting of profits made from the purchase and sale (or sale and purchase) by Indemnitee of securities of the Company within the meaning of Section 16(b) of the Exchange Act or similar provisions of state statutory law or common law[, or from the purchase or sale by Indemnitee of such securities in violation of Section 306 of the Sarbanes-Oxley Act of 2002 (“SOX”)];

(c) to indemnify for any reimbursement of, or repayment to, the Company by Indemnitee of (i) any bonus or other incentive-based or equity-based compensation or of any profits realized by Indemnitee from the sale of securities of the Company pursuant to the terms of (A) Section 304 of SOX, (B) Exchange Act Rule 10D-1 or (C) any formal policy of the Company adopted by the Board (or a committee thereof) or (ii) any other remuneration paid to Indemnitee if it shall be determined by a final judgment or other final adjudication that payment of such remuneration was or would have been in violation of law;

6

(d) to indemnify with respect to any Proceeding, or part thereof, brought by Indemnitee against the Company, any legal entity which it controls, any director or officer thereof or any third party, unless (i) the Board has consented to the initiation of such Proceeding or part thereof and (ii) the Company provides the indemnification, in its sole discretion, pursuant to the powers vested in the Company under applicable law; provided, however, that this Section 7(d) shall not apply to (A) counterclaims or affirmative defenses asserted by Indemnitee in an action brought against Indemnitee or (B) any action brought by Indemnitee for indemnification or advancement from the Company under this Agreement or under any directors’ and officers’ liability insurance policies maintained by the Company in the suit for which indemnification or advancement is being sought as described in Section 12; or

(e) to provide any indemnification or advancement of expenses that is prohibited by applicable law (as such law exists at the time payment would otherwise be required pursuant to this Agreement).

Section 8. Advancement of Expenses. Subject to Section 9(b), the Company shall advance the Expenses incurred by Indemnitee in connection with any Proceeding, and such advancement shall be made within thirty (30) days after the receipt by the Company of a statement or statements requesting such advances (including any invoices received by Indemnitee, which such invoices may be redacted as necessary to avoid the waiver of any privilege accorded by applicable law) from time to time, whether prior to or after final disposition of any Proceeding. Advances shall be unsecured and interest free. Advances shall be made without regard to Indemnitee’s (i) ability to repay the expenses, (ii) ultimate entitlement to indemnification under the other provisions of this Agreement and (iii) entitlement to and availability of insurance coverage, including advancement, payment or reimbursement of defense costs, expenses or covered loss under the provisions of any applicable insurance policy (including, without limitation, whether such advancement, payment or reimbursement is withheld, conditioned or delayed by the insurer(s)). Indemnitee shall qualify for advances upon the execution and delivery to the Company of this Agreement which shall constitute an undertaking providing that Indemnitee undertakes to the fullest extent required by law to repay the advance if and to the extent that it is ultimately determined by a court of competent jurisdiction in a final judgment, not subject to appeal, that Indemnitee is not entitled to be indemnified by the Company. No other form of undertaking shall be required. The right to advances under this paragraph shall in all events continue until final disposition of any Proceeding, including any appeal therein. Nothing in this Section 8 shall limit Indemnitee’s right to advancement pursuant to Section 12(e) of this Agreement.

Section 9. Procedure for Notification and Defense of Claim.

(a) To obtain indemnification under this Agreement, Indemnitee shall submit to the Company a written request therefor specifying the basis for the claim, the amounts for which Indemnitee is seeking payment under this Agreement and all documentation related thereto as reasonably requested by the Company.

7

(b) In the event that the Company shall be obligated hereunder to provide indemnification for or make any advancement of Expenses with respect to any Proceeding, the Company shall be entitled to assume the defense of such Proceeding, or any claim, issue or matter therein, with counsel approved by Indemnitee (which approval shall not be unreasonably withheld or delayed) upon the delivery to Indemnitee of written notice of the Company’s election to do so. After delivery of such notice, approval of such counsel by Indemnitee and the retention of such counsel by the Company, the Company will not be liable to Indemnitee under this Agreement for any fees or expenses of separate counsel subsequently employed by or on behalf of Indemnitee with respect to the same Proceeding; provided that (i) Indemnitee shall have the right to employ separate counsel in any such Proceeding at Indemnitee’s expense and (ii) if (A) the employment of separate counsel by Indemnitee has been previously authorized by the Company, (B) Indemnitee shall have reasonably concluded that there may be a conflict of interest between the Company and Indemnitee in the conduct of such defense, (C) the Company shall not continue to retain such counsel to defend such Proceeding or (D) a Change in Control shall have occurred, then the fees and expenses actually and reasonably incurred by Indemnitee with respect to his or her separate counsel shall be Expenses hereunder.

(c) In the event that the Company does not assume the defense in a Proceeding pursuant to paragraph (b) above, then the Company will be entitled to participate in the Proceeding at its own expense.

(d) The Company shall not be liable to indemnify Indemnitee under this Agreement for any amounts paid in settlement of any Proceeding effected without its prior written consent (which consent shall not be unreasonably withheld or delayed). Without limiting the generality of the foregoing, the fact that an insurer under an applicable insurance policy delays or is unwilling to consent to such settlement or is or may be in breach of its obligations under such policy, or the fact that directors’ and officers’ liability insurance is otherwise unavailable or not maintained by the Company, may not be taken into account by the Company in determining whether to provide its consent. The Company shall not, without the prior written consent of Indemnitee (which consent shall not be unreasonably withheld or delayed), enter into any settlement which (i) includes an admission of fault of Indemnitee, any non-monetary remedy imposed on Indemnitee or any monetary damages for which Indemnitee is not wholly and actually indemnified hereunder or (ii) with respect to any Proceeding with respect to which Indemnitee may be or is made a party or may be otherwise entitled to seek indemnification hereunder, does not include the full release of Indemnitee from all liability in respect of such Proceeding.

Section 10. Procedure Upon Application for Indemnification.

(a) Upon written request by Indemnitee for indemnification pursuant to Section 9(a), a determination, if such determination is required by applicable law, with respect to Indemnitee’s entitlement to indemnification hereunder shall be made in the specific case by one of the following methods: (i) by a majority vote of the disinterested directors, even though less than a quorum; (ii) by a committee of disinterested directors designated by a majority vote of the disinterested directors, even though less than a quorum; or (iii) if there are no disinterested directors or if the disinterested directors so direct, by Independent Counsel in a written opinion to the Board. For purposes hereof, disinterested directors are those members of the Board who are not parties to the action, suit or proceeding in respect of which indemnification is sought. In the case that such determination is made by Independent Counsel, a copy of Independent Counsel’s written opinion shall be delivered to Indemnitee and, if it is so determined that Indemnitee is

8

entitled to indemnification, payment to Indemnitee shall be made within thirty (30) days after such determination. Indemnitee shall cooperate with the Independent Counsel or the Company, as applicable, in making such determination with respect to Indemnitee’s entitlement to indemnification, including providing to such counsel or the Company, upon reasonable advance request, any documentation or information which is not privileged or otherwise protected from disclosure and which is reasonably available to Indemnitee and reasonably necessary to such determination. The Company shall likewise cooperate with Indemnitee and Independent Counsel, if applicable, in making such determination with respect to Indemnitee’s entitlement to indemnification, including providing to such counsel and Indemnitee, upon reasonable advance request, any documentation or information which is not privileged or otherwise protected from disclosure and which is reasonably available to the Company and reasonably necessary to such determination. Any out-of-pocket costs or expenses (including reasonable attorneys’ fees and disbursements) actually and reasonably incurred by Indemnitee in so cooperating with the Independent Counsel or the Company shall be borne by the Company (irrespective of the determination as to Indemnitee’s entitlement to indemnification) and the Company hereby indemnifies and agrees to hold Indemnitee harmless therefrom.

(b) If the determination of entitlement to indemnification is to be made by Independent Counsel pursuant to Section 10(a), the Independent Counsel shall be selected by the Board. Indemnitee may, within ten (10) days after written notice of such selection, deliver to the Company a written objection to such selection; provided, however, that such objection may be asserted only on the ground that the Independent Counsel so selected does not meet the requirements of “Independent Counsel” as defined in Section 2 of this Agreement, and the objection shall set forth with particularity the factual basis of such assertion. Absent a proper and timely objection, the Person so selected shall act as Independent Counsel. If such written objection is so made and substantiated, the Independent Counsel so selected may not serve as Independent Counsel unless and until such objection is withdrawn or the Delaware Court has determined that such objection is without merit. If, within twenty (20) days after the later of (i) submission by Indemnitee of a written request for indemnification pursuant to Section 9(a) and (ii) the final disposition of the Proceeding, including any appeal therein, no Independent Counsel shall have been selected without objection, either Indemnitee or the Company may petition the Delaware Court for resolution of any objection which shall have been made by Indemnitee or the Company to the selection of Independent Counsel and/or for the appointment as Independent Counsel of a Person selected by the court or by such other Person as the court shall designate. The Person with respect to whom all objections are so resolved or the Person so appointed shall act as Independent Counsel under Section 10(a) hereof. Upon the due commencement of any judicial proceeding or arbitration pursuant to Section 12(a) of this Agreement, Independent Counsel shall be discharged and relieved of any further responsibility in such capacity (subject to the applicable standards of professional conduct then prevailing).

(c) Notwithstanding anything to the contrary contained in this Agreement, the determination of entitlement to indemnification under this Agreement shall be made without regard to the Indemnitee’s entitlement to and availability of insurance coverage, including advancement, payment or reimbursement of defense costs, expenses or covered loss under the provisions of any applicable insurance policy (including, without limitation, whether such advancement, payment or reimbursement is withheld, conditioned or delayed by the insurer(s)).

9

Section 11. Presumptions and Effect of Certain Proceedings.

(a) To the extent permitted by applicable law, in making a determination with respect to entitlement to indemnification hereunder, it shall be presumed that Indemnitee is entitled to indemnification under this Agreement if Indemnitee has submitted a request for indemnification in accordance with Section 9(a) of this Agreement, and the Company shall have the burden of proof and the burden of persuasion by clear and convincing evidence to overcome that presumption in connection with the making of any determination contrary to that presumption.

(b) The termination of any Proceeding or of any claim, issue or matter therein, by judgment, order, settlement or conviction, or upon a plea of guilty, nolo contendere or its equivalent, shall not (except as otherwise expressly provided in this Agreement) of itself adversely affect the right of Indemnitee to indemnification or create a presumption that Indemnitee did not act in good faith and in a manner which he or she reasonably believed to be in or not opposed to the best interests of the Company or, with respect to any criminal Proceeding, that Indemnitee had reasonable cause to believe that his or her conduct was unlawful.

(c) Indemnitee shall be deemed to have acted in good faith if Indemnitee’s actions based on the records or books of account of the Company or any other Enterprise, including financial statements, or on information supplied to Indemnitee by the directors, officers, agents or employees of the Company or any other Enterprise in the course of their duties, or on the advice of legal counsel for the Company or any other Enterprise or on information or records given or reports made to the Company or any other Enterprise by an independent certified public accountant or by an appraiser or other expert selected with reasonable care by the Company or any other Enterprise. The provisions of this Section 11(c) shall not be deemed to be exclusive or to limit in any way the other circumstances in which Indemnitee may be deemed to have met the applicable standard of conduct set forth in this Agreement. In addition, the knowledge and/or actions, or failure to act, of any director, manager, partner, officer, employee, agent or trustee of the Company, any subsidiary of the Company, or any Enterprise shall not be imputed to Indemnitee for purposes of determining the right to indemnification under this Agreement. Whether or not the foregoing provisions of this Section 11(c) are satisfied, it shall in any event be presumed that Indemnitee has at all times acted in good faith and in a manner Indemnitee reasonably believed to be in or not opposed to the best interests of the Company. Anyone seeking to overcome this presumption shall have the burden of proof and the burden of persuasion by clear and convincing evidence.

Section 12. Remedies of Indemnitee.

(a) Subject to Section 12(f), in the event that (i) a determination is made pursuant to Section 10 of this Agreement that Indemnitee is not entitled to indemnification under this Agreement, (ii) advancement of Expenses is not timely made pursuant to Section 8 of this Agreement, (iii) no determination of entitlement to indemnification shall have been made pursuant to Section 10(a) of this Agreement within sixty (60) days after receipt by the Company of the request for indemnification for which a determination is to be made other than by Independent Counsel, (iv) payment of indemnification or reimbursement of expenses is not made

10

pursuant to Section 5 or 6 or the last sentence of Section 10(a) of this Agreement within thirty (30) days after receipt by the Company of a written request therefor (including any invoices received by Indemnitee, which such invoices may be redacted as necessary to avoid the waiver of any privilege accorded by applicable law) or (v) payment of indemnification pursuant to Section 3 or 4 of this Agreement is not made within thirty (30) days after a determination has been made that Indemnitee is entitled to indemnification, Indemnitee shall be entitled to an adjudication by the Delaware Court of his or her entitlement to such indemnification or advancement. Alternatively, Indemnitee, at his or her option, may seek an award in arbitration to be conducted by a single arbitrator pursuant to the Commercial Arbitration Rules of the American Arbitration Association. Indemnitee shall commence such proceeding seeking an adjudication or an award in arbitration within 180 days following the date on which Indemnitee first has the right to commence such proceeding pursuant to this Section 12(a); provided, however, that the foregoing time limitation shall not apply in respect of a proceeding brought by Indemnitee to enforce his or her rights under Section 5 of this Agreement. The Company shall not oppose Indemnitee’s right to seek any such adjudication or award in arbitration.

(b) In the event that a determination shall have been made pursuant to Section 10(a) of this Agreement that Indemnitee is not entitled to indemnification, any judicial proceeding or arbitration commenced pursuant to this Section 12 shall be conducted in all respects as a de novo trial, or arbitration, on the merits and Indemnitee shall not be prejudiced by reason of that adverse determination. In any judicial proceeding or arbitration commenced pursuant to this Section 12, the Company shall have the burden of proving Indemnitee is not entitled to indemnification or advancement, as the case may be.

(c) If a determination shall have been made pursuant to Section 10(a) of this Agreement that Indemnitee is entitled to indemnification, the Company shall be bound by such determination in any judicial proceeding or arbitration commenced pursuant to this Section 12, absent (i) a misstatement by Indemnitee of a material fact, or an omission of a material fact necessary to make Indemnitee’s statement not materially misleading, in connection with the request for indemnification or (ii) a prohibition of such indemnification under applicable law.

(d) The Company shall be precluded from asserting in any judicial proceeding or arbitration commenced pursuant to this Section 12 that the procedures and presumptions of this Agreement are not valid, binding and enforceable and shall stipulate in any such court or before any such arbitrator that the Company is bound by all the provisions of this Agreement.

(e) The Company shall indemnify Indemnitee to the fullest extent permitted by law against any and all Enforcement Expenses and, if requested by Indemnitee, shall (within thirty (30) days after receipt by the Company of a written request therefor) advance, to the extent not prohibited by law, such Enforcement Expenses to Indemnitee, which are incurred by Indemnitee in connection with any action brought by Indemnitee for indemnification or advancement from the Company under this Agreement or under any directors’ and officers’ liability insurance policies maintained by the Company in the suit for which indemnification or advancement is being sought. Such written request for advancement shall include invoices received by Indemnitee in connection with such Enforcement Expenses but, in the case of invoices in connection with legal services, any references to legal work performed or to expenditures made that would cause Indemnitee to waive any privilege accorded by applicable law need not be included with the invoice.

11

(f) Notwithstanding anything in this Agreement to the contrary, no determination as to entitlement to indemnification under this Agreement shall be required to be made prior to the final disposition of the Proceeding, including any appeal therein.

Section 13. Non-exclusivity; Survival of Rights; Insurance; Subrogation.

(a) The rights of indemnification and to receive advancement as provided by this Agreement shall not be deemed exclusive of any other rights to which Indemnitee may at any time be entitled under applicable law, the Charter, the Bylaws, any agreement, a vote of stockholders or a resolution of directors or otherwise. No amendment, alteration or repeal of this Agreement or of any provision hereof shall limit or restrict any right of Indemnitee under this Agreement in respect of any action taken or omitted by such Indemnitee in his or her Corporate Status prior to such amendment, alteration or repeal. To the extent that a change in Delaware law, whether by statute or judicial decision, permits greater indemnification or advancement than would be afforded currently under the Charter, Bylaws and this Agreement, it is the intent of the parties hereto that Indemnitee shall enjoy by this Agreement the greater benefits so afforded by such change. No right or remedy herein conferred is intended to be exclusive of any other right or remedy, and every other right and remedy shall be cumulative and in addition to every other right and remedy given hereunder or now or hereafter existing at law or in equity or otherwise. The assertion or employment of any right or remedy hereunder, or otherwise, shall not prevent the concurrent assertion or employment of any other right or remedy.

(b) To the extent that the Company maintains an insurance policy or policies providing liability insurance for directors, managers, partners, officers, employees, agents or trustees of the Company or of any other Enterprise, Indemnitee shall be covered by such policy or policies in accordance with its or their terms to the maximum extent of the coverage available for any such director, manager, partner, officer, employee, agent or trustee under such policy or policies. If, at the time of the receipt of a notice of a claim pursuant to the terms hereof, the Company has director and officer liability insurance in effect, the Company shall give prompt notice of such claim to the insurers in accordance with the procedures set forth in the respective policies. The Company shall thereafter take all necessary or desirable action to cause such insurers to pay, on behalf of the Indemnitee, all amounts payable as a result of such Proceeding in accordance with the terms of such policies. Upon request of Indemnitee, the Company shall also promptly provide to Indemnitee: (i) copies of all of the Company’s potentially applicable directors’ and officers’ liability insurance policies, (ii) copies of such notices delivered to the applicable insurers and (iii) copies of all subsequent communications and correspondence between the Company and such insurers regarding the Proceeding.

(c) In the event of any payment under this Agreement, the Company shall be subrogated to the extent of such payment to all of the rights of recovery of Indemnitee, who shall execute all papers required and take all action necessary to secure such rights, including execution of such documents as are necessary to enable the Company to bring suit to enforce such rights.

12

(d) The Company’s obligation to provide indemnification or advancement hereunder to Indemnitee who is or was serving at the request of the Company as a director, manager, partner, officer, employee, agent or trustee of any other Enterprise shall be reduced by any amount Indemnitee has actually received as indemnification or advancement from such other Enterprise.

Section 14. Duration of Agreement. This Agreement shall continue until and terminate upon the later of: (a) ten (10) years after the date that Indemnitee shall have ceased to serve as an officer of the Company or (b) one (1) year after the final termination of any Proceeding, including any appeal, then pending in respect of which Indemnitee is granted rights of indemnification or advancement hereunder and of any proceeding commenced by Indemnitee pursuant to Section 12 of this Agreement relating thereto. This Agreement shall be binding upon the Company and its successors and assigns and shall inure to the benefit of Indemnitee and his or her heirs, executors and administrators. The Company shall require and cause any successor (whether direct or indirect by purchase, merger, consolidation or otherwise) to all, substantially all or a substantial part, of the business and/or assets of the Company, by written agreement in form and substance satisfactory to Indemnitee, expressly to assume and agree to perform this Agreement in the same manner and to the same extent that the Company would be required to perform if no such succession had taken place.

Section 15. Severability. If any provision or provisions of this Agreement shall be held to be invalid, illegal or unenforceable for any reason whatsoever: (a) the validity, legality and enforceability of the remaining provisions of this Agreement (including, without limitation, each portion of any section of this Agreement containing any such provision held to be invalid, illegal or unenforceable, that is not itself invalid, illegal or unenforceable) shall not in any way be affected or impaired thereby and shall remain enforceable to the fullest extent permitted by law; (b) such provision or provisions shall be deemed reformed to the extent necessary to conform to applicable law and to give the maximum effect to the intent of the parties hereto; and (c) to the fullest extent possible, the provisions of this Agreement (including, without limitation, each portion of any section of this Agreement containing any such provision held to be invalid, illegal or unenforceable, that is not itself invalid, illegal or unenforceable) shall be construed so as to give effect to the intent manifested thereby.

Section 16. Enforcement.

(a) The Company expressly confirms and agrees that it has entered into this Agreement and assumed the obligations imposed on it hereby in order to induce Indemnitee [to serve or continue to serve] as an officer of the Company, and the Company acknowledges that Indemnitee is relying upon this Agreement in serving as an officer of the Company.

(b) This Agreement constitutes the entire agreement between the parties hereto with respect to the subject matter hereof and supersedes all prior agreements and understandings, oral, written and implied, between the parties hereto with respect to the subject matter hereof; provided, however, that this Agreement is a supplement to and in furtherance of the Charter, the Bylaws and applicable law, and shall not be deemed a substitute therefor, nor to diminish or abrogate any rights of Indemnitee thereunder.

13

Section 17. Modification and Waiver. No supplement, modification or amendment, or waiver of any provision, of this Agreement shall be binding unless executed in writing by the parties thereto. No waiver of any of the provisions of this Agreement shall be deemed or shall constitute a waiver of any other provisions of this Agreement nor shall any waiver constitute a continuing waiver. No supplement, modification or amendment of this Agreement or of any provision hereof shall limit or restrict any right of Indemnitee under this Agreement in respect of any action taken or omitted by such Indemnitee prior to such supplement, modification or amendment.

Section 18. Notice by Indemnitee. Indemnitee agrees promptly to notify the Company in writing upon being served with any summons, citation, subpoena, complaint, indictment, information or other document relating to any Proceeding or matter which may be subject to indemnification, reimbursement or advancement as provided hereunder. The failure of Indemnitee to so notify the Company or any delay in notification shall not relieve the Company of any obligation which it may have to Indemnitee under this Agreement or otherwise, unless, and then only to the extent that, the Company did not otherwise learn of the Proceeding and such delay is materially prejudicial to the Company’s ability to defend such Proceeding or matter; and, provided, further, that notice will be deemed to have been given without any action on the part of Indemnitee in the event the Company is a party to the same Proceeding.

Section 19. Notices. All notices, requests, demands and other communications under this Agreement shall be in writing and shall be deemed to have been duly given if (i) delivered by hand and receipted for by the party to whom said notice or other communication shall have been directed, (ii) mailed by certified or registered mail with postage prepaid, on the third business day after the date on which it is so mailed, (iii) mailed by reputable overnight courier and receipted for by the party to whom said notice or other communication shall have been directed or (iv) sent by facsimile transmission, with receipt of oral confirmation that such transmission has been received:

One Kendall Square, Building 600-700

Suite 6-401

Cambridge, MA 02139

Attention: Chief Executive Officer

or to any other address as may have been furnished to Indemnitee by the Company.

Section 20. Contribution. To the fullest extent permissible under applicable law, if the indemnification provided for in this Agreement is unavailable to Indemnitee for any reason whatsoever, the Company, in lieu of indemnifying Indemnitee, shall contribute to the amount incurred by Indemnitee, whether for judgments, fines, penalties, excise taxes, amounts paid or to

14

be paid in settlement and/or for Expenses, in connection with any Proceeding in such proportion as is deemed fair and reasonable in light of all of the circumstances in order to reflect (i) the relative benefits received by the Company and Indemnitee in connection with the event(s) and/or transaction(s) giving rise to such Proceeding; and/or (ii) the relative fault of the Company (and its directors, officers, employees and agents) and Indemnitee in connection with such event(s) and/or transactions.

Section 21. Internal Revenue Code Section 409A. The Company intends for this Agreement to comply with the Indemnification exception under Section 1.409A-1(b)(10) of the regulations promulgated under the Internal Revenue Code of 1986, as amended (the “Code”), which provides that indemnification of, or the purchase of an insurance policy providing for payments of, all or part of the expenses incurred or damages paid or payable by Indemnitee with respect to a bona fide claim against Indemnitee or the Company do not provide for a deferral of compensation, subject to Section 409A of the Code, where such claim is based on actions or failures to act by Indemnitee in his or her capacity as a service provider of the Company. The parties intend that this Agreement be interpreted and construed with such intent.

Section 22. Applicable Law and Consent to Jurisdiction. This Agreement and the legal relations among the parties shall be governed by, and construed and enforced in accordance with, the laws of the State of Delaware, without regard to its conflict of laws rules. Except with respect to any arbitration commenced by Indemnitee pursuant to Section 12(a) of this Agreement, the Company and Indemnitee hereby irrevocably and unconditionally (i) agree that any action or proceeding arising out of or in connection with this Agreement shall be brought only in the Delaware Court, and not in any other state or federal court in the United States of America or any court in any other country, (ii) consent to submit to the exclusive jurisdiction of the Delaware Court for purposes of any action or proceeding arising out of or in connection with this Agreement, (iii) consent to service of process at the address set forth in Section 19 of this Agreement with the same legal force and validity as if served upon such party personally within the State of Delaware, (iv) waive any objection to the laying of venue of any such action or proceeding in the Delaware Court and (v) waive, and agree not to plead or to make, any claim that any such action or proceeding brought in the Delaware Court has been brought in an improper or inconvenient forum.

Section 23. Headings. The headings of the paragraphs of this Agreement are inserted for convenience only and shall not be deemed to constitute part of this Agreement or to affect the construction thereof.

Section 24. Identical Counterparts. This Agreement may be executed in one or more counterparts, each of which shall for all purposes be deemed to be an original but all of which together shall constitute one and the same Agreement. Only one such counterpart signed by the party against whom enforceability is sought needs to be produced to evidence the existence of this Agreement.

Section 25. Monetary Damages Insufficient/Specific Enforcement. The Company and Indemnitee agree that a monetary remedy for breach of this Agreement may be inadequate, impracticable and difficult of proof, and further agree that such breach may cause Indemnitee irreparable harm. Accordingly, the parties hereto agree that Indemnitee may enforce this

15

Agreement by seeking injunctive relief and/or specific performance hereof, without any necessity of showing actual damage or irreparable harm (having agreed that actual and irreparable harm will result in not forcing the Company to specifically perform its obligations pursuant to this Agreement) and that by seeking injunctive relief and/or specific performance, Indemnitee shall not be precluded from seeking or obtaining any other relief to which he may be entitled. The Company and Indemnitee further agree that Indemnitee shall be entitled to such specific performance and injunctive relief, including temporary restraining orders, preliminary injunctions and permanent injunctions, without the necessity of posting bonds or other undertakings in connection therewith. The Company acknowledges that in the absence of a waiver, a bond or undertaking may be required of Indemnitee by the Court, and the Company hereby waives any such requirement of a bond or undertaking.

[Remainder of Page Intentionally Left Blank]

16

IN WITNESS WHEREOF, the parties have caused this Agreement to be signed as of the day and year first above written.

Exhibit 10.7

KORRO BIO, INC.

AMENDED AND RESTATED

FORM OF DIRECTOR INDEMNIFICATION AGREEMENT

This Indemnification Agreement (“Agreement”) is made as of ________________ by and between Korro Bio, Inc., a Delaware corporation (the “Company”), and ____________ (“Indemnitee”).

RECITALS

WHEREAS, the Company desires to attract and retain the services of highly qualified individuals, such as Indemnitee, to serve the Company;

WHEREAS, in order to induce Indemnitee to [provide or continue to provide] services to the Company, the Company wishes to provide for the indemnification of, and advancement of expenses to, Indemnitee to the maximum extent permitted by law;

WHEREAS, the Certificate of Incorporation (the “Charter”) and the Bylaws (the “Bylaws”) of the Company require indemnification of the officers and directors of the Company, and Indemnitee may also be entitled to indemnification pursuant to the General Corporation Law of the State of Delaware (the “DGCL”);

WHEREAS, the Charter, the Bylaws and the DGCL expressly provide that the indemnification provisions set forth therein are not exclusive, and thereby contemplate that contracts may be entered into between the Company and members of the board of directors, officers and other persons with respect to indemnification;

WHEREAS, the Board of Directors of the Company (the “Board”) has determined that the increased difficulty in attracting and retaining highly qualified persons such as Indemnitee is detrimental to the best interests of the Company’s stockholders;

WHEREAS, it is reasonable and prudent for the Company contractually to obligate itself to indemnify, and to advance expenses on behalf of, such persons to the fullest extent permitted by applicable law, regardless of any amendment or revocation of the Charter or the Bylaws, so that they will serve or continue to serve the Company free from undue concern that they will not be so indemnified;

WHEREAS, this Agreement is a supplement to and in furtherance of the indemnification provided in the Charter, the Bylaws and any resolutions adopted pursuant thereto, and shall not be deemed a substitute therefor, nor to diminish or abrogate any rights of Indemnitee thereunder; and

[WHEREAS, Indemnitee has certain rights to indemnification and/or insurance provided by [Name of Fund/Sponsor] which Indemnitee and [Name of Fund/Sponsor] intend to be secondary to the primary obligation of the Company to indemnify Indemnitee as provided in this Agreement, with the Company’s acknowledgment and agreement to the foregoing being a material condition to Indemnitee’s willingness to [serve or continue to serve] on the Board.]

NOW, THEREFORE, in consideration of the premises and the covenants contained herein, the Company and Indemnitee do hereby covenant and agree as follows:

Section 1. Services to the Company. Indemnitee agrees to serve as a director of the Company. Indemnitee may at any time and for any reason resign from such position (subject to any other contractual obligation or any obligation imposed by law), in which event the Company shall have no obligation under this Agreement to continue Indemnitee in such position. This Agreement shall not be deemed an employment contract between the Company (or any of its subsidiaries or any Enterprise) and Indemnitee.

Section 2. Definitions.

As used in this Agreement:

(a) “Affiliate” and “Associate” shall have the respective meanings ascribed to such terms in Rule 12b-2 of the General Rules and Regulations under the Securities Exchange Act of 1934, as amended, the “Exchange Act”), as in effect on the date of this Agreement; provided, however, that no Person who is a director or officer of the Company shall be deemed an Affiliate or an Associate of any other director or officer of the Company solely as a result of his or her position as director or officer of the Company.

(b) A Person shall be deemed the “Beneficial Owner” of, and shall be deemed to “Beneficially Own” and have “Beneficial Ownership” of, any securities:

(i) which such Person or any of such Person’s Affiliates or Associates, directly or indirectly, Beneficially Owns (as determined pursuant to Rule 13d-3 of the Rules under the Exchange Act, as in effect on the date of this Agreement);

(ii) which such Person or any of such Person’s Affiliates or Associates, directly or indirectly, has: (A) the legal, equitable or contractual right or obligation to acquire (whether directly or indirectly and whether exercisable immediately or only after the passage of time, compliance with regulatory requirements, satisfaction of one or more conditions (whether or not within the control of such Person) or otherwise) upon the exercise of any conversion rights, exchange rights, rights, warrants or options, or otherwise; (B) the right to vote pursuant to any agreement, arrangement or understanding (whether or not in writing); or (C) the right to dispose of pursuant to any agreement, arrangement or understanding (whether or not in writing) (other than customary arrangements with and between underwriters and selling group members with respect to a bona fide public offering of securities);

2

(iii) which are Beneficially Owned, directly or indirectly, by any other Person (or any Affiliate or Associate thereof) with which such Person or any of such Person’s Affiliates or Associates has any agreement, arrangement or understanding (whether or not in writing) (other than customary agreements with and between underwriters and selling group members with respect to a bona fide public offering of securities) for the purpose of acquiring, holding, voting or disposing of any securities of the Company; or

(iv) that are the subject of a derivative transaction entered into by such Person or any of such Person’s Affiliates or Associates, including, for these purposes, any derivative security acquired by such Person or any of such Person’s Affiliates or Associates that gives such Person or any of such Person’s Affiliates or Associates the economic equivalent of ownership of an amount of securities due to the fact that the value of the derivative security is explicitly determined by reference to the price or value of such securities, or that provides such Person or any of such Person’s Affiliates or Associates an opportunity, directly or indirectly, to profit or to share in any profit derived from any change in the value of such securities, in any case without regard to whether (A) such derivative security conveys any voting rights in such securities to such Person or any of such Person’s Affiliates or Associates; (B) the derivative security is required to be, or capable of being, settled through delivery of such securities; or (C) such Person or any of such Person’s Affiliates or Associates may have entered into other transactions that hedge the economic effect of such derivative security;

Notwithstanding the foregoing, no Person engaged in business as an underwriter of securities shall be deemed the Beneficial Owner of any securities acquired through such Person’s participation as an underwriter in good faith in a firm commitment underwriting.

(c) A “Change in Control” shall be deemed to occur upon the earliest to occur after the date of this Agreement of any of the following events:

(i) Acquisition of Stock by Third Party. Any Person is or becomes the Beneficial Owner (as defined above), directly or indirectly, of securities of the Company representing fifty percent (50%) or more of the combined voting power of the Company’s then outstanding securities unless the change in relative Beneficial Ownership of the Company’s securities by any Person results solely from a reduction in the aggregate number of outstanding shares of securities entitled to vote generally in the election of directors, provided that a Change of Control shall be deemed to have occurred if subsequent to such reduction such Person becomes the Beneficial Owner, directly or indirectly, of any additional securities of the Company conferring upon such Person any additional voting power;

(ii) Change in Board of Directors. During any period of two (2) consecutive years (not including any period prior to the execution of this Agreement), individuals who at the beginning of such period constitute the Board, and any new director (other than a director designated by a person who has entered into an agreement with the Company to effect a transaction described in Sections 2(c)(i), 2(c)(iii) or 2(c)(iv)) whose election by the Board or nomination for election by the Company’s stockholders was approved by a vote of at least two-thirds of the directors then still in office who either were directors at the beginning of the period or whose election or nomination for election was previously so approved, cease for any reason to constitute at least a majority of the members of the Board;

3

(iii) Corporate Transactions. The effective date of a merger or consolidation of the Company with any other entity, other than a merger or consolidation which would result in the voting securities of the Company outstanding immediately prior to such merger or consolidation continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving or successor entity) more than 50% of the combined voting power of the voting securities of the surviving or successor entity outstanding immediately after such merger or consolidation and with the power to elect at least a majority of the board of directors or other governing body of such surviving or successor entity;

(iv) Liquidation. The approval by the stockholders of the Company of a complete liquidation of the Company or an agreement for the sale, lease, exchange or other transfer by the Company, in one or a series of related transactions, of all or substantially all of the Company’s assets; and

(v) Other Events. There occurs any other event of a nature that would be required to be reported in response to Item 6(e) of Schedule 14A of Regulation 14A (or a response to any similar item on any similar schedule or form) promulgated under the Exchange Act whether or not the Company is then subject to such reporting requirement.

(d) “Corporate Status” describes the status of a person as a current or former director of the Company or current or former director, manager, partner, officer, employee, agent or trustee of any other Enterprise which such person is or was serving at the request of the Company.

(e) “Enforcement Expenses” shall include all reasonable attorneys’ fees, court costs, transcript costs, fees of experts, travel expenses, duplicating costs, printing and binding costs, telephone charges, postage, delivery service fees and all other out-of-pocket disbursements or expenses of the types customarily incurred in connection with an action to enforce indemnification or advancement rights, or an appeal from such action. Expenses, however, shall not include fees, salaries, wages or benefits owed to Indemnitee.

(f) “Enterprise” shall mean any corporation (other than the Company), partnership, joint venture, trust, employee benefit plan, limited liability company or other legal entity of which Indemnitee is or was serving at the request of the Company as a director, manager, partner, officer, employee, agent or trustee.

(g) “Expenses” shall include all reasonable attorneys’ fees, court costs, transcript costs, fees of experts, travel expenses, duplicating costs, printing and binding costs, telephone charges, postage, delivery service fees and all other out-of-pocket disbursements or expenses of the types customarily incurred in connection with prosecuting, defending, preparing to prosecute or defend, investigating, being or preparing to be a witness in, or otherwise participating in, a Proceeding or an appeal resulting from a Proceeding. Expenses, however, shall not include amounts paid in settlement by Indemnitee, the amount of judgments or fines against Indemnitee or fees, salaries, wages or benefits owed to Indemnitee.

4

(h) “Independent Counsel” means a law firm, or a partner (or, if applicable, member or shareholder) of such a law firm, that is experienced in matters of Delaware corporation law and neither presently is, nor in the past five (5) years has been, retained to represent: (i) the Company, any subsidiary of the Company, any Enterprise or Indemnitee in any matter material to any such party; or (ii) any other party to the Proceeding giving rise to a claim for indemnification hereunder. Notwithstanding the foregoing, the term “Independent Counsel” shall not include any person who, under the applicable standards of professional conduct then prevailing, would have a conflict of interest in representing either the Company or Indemnitee in an action to determine Indemnitee’s rights under this Agreement. The Company agrees to pay the reasonable fees and expenses of the Independent Counsel referred to above and to fully indemnify such counsel against any and all expenses, claims, liabilities and damages arising out of or relating to this Agreement or its engagement pursuant hereto.

(i) “Person” shall mean (i) an individual, a corporation, a partnership, a limited liability company, an association, a joint stock company, a trust, a business trust, a government or political subdivision, any unincorporated organization or any other association or entity including any successor (by merger or otherwise) thereof or thereto, and (ii) a “group” as that term is used for purposes of Section 13(d)(3) of the Exchange Act.

(j) The term “Proceeding” shall include any threatened, pending or completed action, suit, arbitration, alternate dispute resolution mechanism, investigation, inquiry, administrative hearing or any other actual, threatened or completed proceeding, whether brought in the right of the Company or otherwise and whether of a civil, criminal, administrative, regulatory or investigative nature, and whether formal or informal, in which Indemnitee was, is or will be involved as a party or otherwise by reason of the fact that Indemnitee is or was a director of the Company or is or was serving at the request of the Company as a director, manager, partner, officer, employee, agent or trustee of any Enterprise or by reason of any action taken by Indemnitee or of any action taken on his or her part while acting as a director of the Company or while serving at the request of the Company as a director, manager, partner, officer, employee, agent or trustee of any Enterprise, in each case whether or not serving in such capacity at the time any liability or expense is incurred for which indemnification, reimbursement or advancement of expenses can be provided under this Agreement; provided, however, that the term “Proceeding” shall not include any action, suit or arbitration, or part thereof, initiated by Indemnitee to enforce Indemnitee’s rights under this Agreement as provided for in Section 12(a) of this Agreement.

Section 3. Indemnity in Third-Party Proceedings. The Company shall indemnify Indemnitee to the extent set forth in this Section 3 if Indemnitee is, or is threatened to be made, a party to or a participant in any Proceeding, other than a Proceeding by or in the right of the Company to procure a judgment in its favor. Pursuant to this Section 3, Indemnitee shall be indemnified against all Expenses, judgments, fines, penalties, excise taxes and amounts paid in settlement actually and reasonably incurred by Indemnitee or on his or her behalf in connection with such Proceeding or any claim, issue or matter therein, if Indemnitee acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the Company and, in the case of a criminal proceeding, had no reasonable cause to believe that his or her conduct was unlawful.

Section 4. Indemnity in Proceedings by or in the Right of the Company. The Company shall indemnify Indemnitee to the extent set forth in this Section 4 if Indemnitee is, or is threatened to be made, a party to or a participant in any Proceeding by or in the right of the Company to procure a judgment in its favor. Pursuant to this Section 4, Indemnitee shall be

5

indemnified against all Expenses actually and reasonably incurred by Indemnitee or on his or her behalf in connection with such Proceeding or any claim, issue or matter therein, if Indemnitee acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the Company. No indemnification for Expenses shall be made under this Section 4 in respect of any claim, issue or matter as to which Indemnitee shall have been finally adjudged by a court to be liable to the Company, unless and only to the extent that the Delaware Court of Chancery (the “Delaware Court”) shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, Indemnitee is fairly and reasonably entitled to indemnification for such expenses as the Delaware Court shall deem proper.

Section 5. Indemnification for Expenses of a Party Who is Wholly or Partly Successful. Notwithstanding any other provisions of this Agreement and except as provided in Section 7, to the extent that Indemnitee is a party to or a participant in any Proceeding and is successful in such Proceeding or in defense of any claim, issue or matter therein, the Company shall indemnify Indemnitee against all Expenses actually and reasonably incurred by him or her in connection therewith. If Indemnitee is not wholly successful in such Proceeding but is successful as to one or more but less than all claims, issues or matters in such Proceeding, the Company shall indemnify Indemnitee against all Expenses actually and reasonably incurred by Indemnitee or on his or her behalf in connection with each successfully resolved claim, issue or matter. For purposes of this Section and without limitation, the termination of any claim, issue or matter in such a Proceeding by dismissal, with or without prejudice, shall be deemed to be a successful result as to such claim, issue or matter.

Section 6. Reimbursement for Expenses of a Witness or in Response to a Subpoena. Notwithstanding any other provision of this Agreement, to the extent that Indemnitee, by reason of his or her Corporate Status, (i) is a witness in any Proceeding to which Indemnitee is not a party and is not threatened to be made a party or (ii) receives a subpoena with respect to any Proceeding to which Indemnitee is not a party and is not threatened to be made a party, the Company shall reimburse Indemnitee for all Expenses actually and reasonably incurred by him or her or on his or her behalf in connection therewith.

Section 7. Exclusions. Notwithstanding any provision in this Agreement to the contrary, the Company shall not be obligated under this Agreement:

(a) to indemnify for amounts otherwise indemnifiable hereunder (or for which advancement is provided hereunder) if and to the extent that Indemnitee has otherwise actually received such amounts under any insurance policy, contract, agreement or otherwise; provided that the foregoing shall not [i] apply to any personal or umbrella liability insurance maintained by Indemnitee, [or, (ii) affect the rights of Indemnitee or the Fund Indemnitors as set forth in Section 13(c)];

(b) to indemnify for an accounting of profits made from the purchase and sale (or sale and purchase) by Indemnitee of securities of the Company within the meaning of Section 16(b) of the Exchange Act or similar provisions of state statutory law or common law[, or from the purchase or sale by Indemnitee of such securities in violation of Section 306 of the Sarbanes-Oxley Act of 2002 (“SOX”)];

6

(c) to indemnify with respect to any Proceeding, or part thereof, brought by Indemnitee against the Company, any legal entity which it controls, any director or officer thereof or any third party, unless (i) the Board has consented to the initiation of such Proceeding or part thereof and (ii) the Company provides the indemnification, in its sole discretion, pursuant to the powers vested in the Company under applicable law; provided, however, that this Section 7(c) shall not apply to (A) counterclaims or affirmative defenses asserted by Indemnitee in an action brought against Indemnitee or (B) any action brought by Indemnitee for indemnification or advancement from the Company under this Agreement or under any directors’ and officers’ liability insurance policies maintained by the Company in the suit for which indemnification or advancement is being sought as described in Section 12; or

(d) to provide any indemnification or advancement of expenses that is prohibited by applicable law (as such law exists at the time payment would otherwise be required pursuant to this Agreement).

Section 8. Advancement of Expenses. Subject to Section 9(b), the Company shall advance the Expenses incurred by Indemnitee in connection with any Proceeding, and such advancement shall be made within thirty (30) days after the receipt by the Company of a statement or statements requesting such advances (including any invoices received by Indemnitee, which such invoices may be redacted as necessary to avoid the waiver of any privilege accorded by applicable law) from time to time, whether prior to or after final disposition of any Proceeding. Advances shall be unsecured and interest free. Advances shall be made without regard to Indemnitee’s (i) ability to repay the expenses, (ii) ultimate entitlement to indemnification under the other provisions of this Agreement and (iii) entitlement to and availability of insurance coverage, including advancement, payment or reimbursement of defense costs, expenses or covered loss under the provisions of any applicable insurance policy (including, without limitation, whether such advancement, payment or reimbursement is withheld, conditioned or delayed by the insurer(s)). Indemnitee shall qualify for advances upon the execution and delivery to the Company of this Agreement which shall constitute an undertaking providing that Indemnitee undertakes to the fullest extent required by law to repay the advance if and to the extent that it is ultimately determined by a court of competent jurisdiction in a final judgment, not subject to appeal, that Indemnitee is not entitled to be indemnified by the Company. No other form of undertaking shall be required. The right to advances under this paragraph shall in all events continue until final disposition of any Proceeding, including any appeal therein. Nothing in this Section 8 shall limit Indemnitee’s right to advancement pursuant to Section 12(e) of this Agreement.

Section 9. Procedure for Notification and Defense of Claim.

(a) To obtain indemnification under this Agreement, Indemnitee shall submit to the Company a written request therefor specifying the basis for the claim, the amounts for which Indemnitee is seeking payment under this Agreement, and all documentation related thereto as reasonably requested by the Company.

7

(b) In the event that the Company shall be obligated hereunder to provide indemnification for or make any advancement of Expenses with respect to any Proceeding, the Company shall be entitled to assume the defense of such Proceeding, or any claim, issue or matter therein, with counsel approved by Indemnitee (which approval shall not be unreasonably withheld or delayed) upon the delivery to Indemnitee of written notice of the Company’s election to do so. After delivery of such notice, approval of such counsel by Indemnitee and the retention of such counsel by the Company, the Company will not be liable to Indemnitee under this Agreement for any fees or expenses of separate counsel subsequently employed by or on behalf of Indemnitee with respect to the same Proceeding; provided that (i) Indemnitee shall have the right to employ separate counsel in any such Proceeding at Indemnitee’s expense and (ii) if (A) the employment of separate counsel by Indemnitee has been previously authorized by the Company, (B) Indemnitee shall have reasonably concluded that there may be a conflict of interest between the Company and Indemnitee in the conduct of such defense, (C) the Company shall not continue to retain such counsel to defend such Proceeding or (D) a Change in Control shall have occurred, then the fees and expenses actually and reasonably incurred by Indemnitee with respect to his or her separate counsel shall be Expenses hereunder.

(c) In the event that the Company does not assume the defense in a Proceeding pursuant to paragraph (b) above, then the Company will be entitled to participate in the Proceeding at its own expense.

(d) The Company shall not be liable to indemnify Indemnitee under this Agreement for any amounts paid in settlement of any Proceeding effected without its prior written consent (which consent shall not be unreasonably withheld or delayed). Without limiting the generality of the foregoing, the fact that an insurer under an applicable insurance policy delays or is unwilling to consent to such settlement or is or may be in breach of its obligations under such policy, or the fact that directors’ and officers’ liability insurance is otherwise unavailable or not maintained by the Company, may not be taken into account by the Company in determining whether to provide its consent. The Company shall not, without the prior written consent of Indemnitee (which consent shall not be unreasonably withheld or delayed), enter into any settlement which (i) includes an admission of fault of Indemnitee, any non-monetary remedy imposed on Indemnitee or any monetary damages for which Indemnitee is not wholly and actually indemnified hereunder or (ii) with respect to any Proceeding with respect to which Indemnitee may be or is made a party or may be otherwise entitled to seek indemnification hereunder, does not include the full release of Indemnitee from all liability in respect of such Proceeding.

Section 10. Procedure Upon Application for Indemnification.

(a) Upon written request by Indemnitee for indemnification pursuant to Section 9(a), a determination, if such determination is required by applicable law, with respect to Indemnitee’s entitlement to indemnification hereunder shall be made in the specific case by one of the following methods: (x) if a Change in Control shall have occurred, by Independent Counsel in a written opinion to the Board; or (y) if a Change in Control shall not have occurred: (i) by a majority vote of the disinterested directors, even though less than a quorum; (ii) by a committee of disinterested directors designated by a majority vote of the disinterested directors, even though less than a quorum; or (iii) if there are no disinterested directors or if the disinterested directors so direct, by Independent Counsel in a written opinion to the Board. For purposes hereof, disinterested directors are those members of the Board who are not parties to the action, suit or proceeding in respect of which indemnification is sought. In the case that such

8

determination is made by Independent Counsel, a copy of Independent Counsel’s written opinion shall be delivered to Indemnitee and, if it is so determined that Indemnitee is entitled to indemnification, payment to Indemnitee shall be made within thirty (30) days after such determination. Indemnitee shall cooperate with the Independent Counsel or the Company, as applicable, in making such determination with respect to Indemnitee’s entitlement to indemnification, including providing to such counsel or the Company, upon reasonable advance request, any documentation or information which is not privileged or otherwise protected from disclosure and which is reasonably available to Indemnitee and reasonably necessary to such determination. The Company shall likewise cooperate with Indemnitee and Independent Counsel, if applicable, in making such determination with respect to Indemnitee’s entitlement to indemnification, including providing to such counsel and Indemnitee, upon reasonable advance request, any documentation or information which is not privileged or otherwise protected from disclosure and which is reasonably available to the Company and reasonably necessary to such determination. Any out-of-pocket costs or expenses (including reasonable attorneys’ fees and disbursements) actually and reasonably incurred by Indemnitee in so cooperating with the Independent Counsel or the Company shall be borne by the Company (irrespective of the determination as to Indemnitee’s entitlement to indemnification) and the Company hereby indemnifies and agrees to hold Indemnitee harmless therefrom.

(b) If the determination of entitlement to indemnification is to be made by Independent Counsel pursuant to Section 10(a), the Independent Counsel shall be selected by the Board if a Change in Control shall not have occurred or, if a Change in Control shall have occurred, by Indemnitee. Indemnitee or the Company, as the case may be, may, within ten (10) days after written notice of such selection, deliver to the Company or Indemnitee, as the case may be, a written objection to such selection; provided, however, that such objection may be asserted only on the ground that the Independent Counsel so selected does not meet the requirements of “Independent Counsel” as defined in Section 2 of this Agreement, and the objection shall set forth with particularity the factual basis of such assertion. Absent a proper and timely objection, the person so selected shall act as Independent Counsel. If such written objection is so made and substantiated, the Independent Counsel so selected may not serve as Independent Counsel unless and until such objection is withdrawn or the Delaware Court has determined that such objection is without merit. If, within twenty (20) days after the later of (i) submission by Indemnitee of a written request for indemnification pursuant to Section 9(a), and (ii) the final disposition of the Proceeding, including any appeal therein, no Independent Counsel shall have been selected without objection, either Indemnitee or the Company may petition the Delaware Court for resolution of any objection which shall have been made by Indemnitee or the Company to the selection of Independent Counsel and/or for the appointment as Independent Counsel of a person selected by the court or by such other person as the court shall designate. The person with respect to whom all objections are so resolved or the person so appointed shall act as Independent Counsel under Section 10(a) hereof. Upon the due commencement of any judicial proceeding or arbitration pursuant to Section 12(a) of this Agreement, Independent Counsel shall be discharged and relieved of any further responsibility in such capacity (subject to the applicable standards of professional conduct then prevailing).

9

(c) Notwithstanding anything to the contrary contained in this Agreement, the determination of entitlement to indemnification under this Agreement shall be made without regard to the Indemnitee’s entitlement to and availability of insurance coverage, including advancement, payment or reimbursement of defense costs, expenses or covered loss under the provisions of any applicable insurance policy (including, without limitation, whether such advancement, payment or reimbursement is withheld, conditioned or delayed by the insurer(s)).

Section 11. Presumptions and Effect of Certain Proceedings.

(a) To the extent permitted by applicable law, in making a determination with respect to entitlement to indemnification hereunder, it shall be presumed that Indemnitee is entitled to indemnification under this Agreement if Indemnitee has submitted a request for indemnification in accordance with Section 9(a) of this Agreement, and the Company shall have the burden of proof and the burden of persuasion by clear and convincing evidence to overcome that presumption in connection with the making of any determination contrary to that presumption.

(b) The termination of any Proceeding or of any claim, issue or matter therein, by judgment, order, settlement or conviction, or upon a plea of guilty, nolo contendere or its equivalent, shall not (except as otherwise expressly provided in this Agreement) of itself adversely affect the right of Indemnitee to indemnification or create a presumption that Indemnitee did not act in good faith and in a manner which he or she reasonably believed to be in or not opposed to the best interests of the Company or, with respect to any criminal Proceeding, that Indemnitee had reasonable cause to believe that his or her conduct was unlawful.

(c) Indemnitee shall be deemed to have acted in good faith if Indemnitee’s actions based on the records or books of account of the Company or any other Enterprise, including financial statements, or on information supplied to Indemnitee by the directors, officers, agents or employees of the Company or any other Enterprise in the course of their duties, or on the advice of legal counsel for the Company or any other Enterprise or on information or records given or reports made to the Company or any other Enterprise by an independent certified public accountant or by an appraiser or other expert selected with reasonable care by the Company or any other Enterprise. The provisions of this Section 11(c) shall not be deemed to be exclusive or to limit in any way the other circumstances in which Indemnitee may be deemed to have met the applicable standard of conduct set forth in this Agreement. In addition, the knowledge and/or actions, or failure to act, of any director, manager, partner, officer, employee, agent or trustee of the Company, any subsidiary of the Company, or any Enterprise shall not be imputed to Indemnitee for purposes of determining the right to indemnification under this Agreement. Whether or not the foregoing provisions of this Section 11(c) are satisfied, it shall in any event be presumed that Indemnitee has at all times acted in good faith and in a manner Indemnitee reasonably believed to be in or not opposed to the best interests of the Company. Anyone seeking to overcome this presumption shall have the burden of proof and the burden of persuasion by clear and convincing evidence.

10

Section 12. Remedies of Indemnitee.

(a) Subject to Section 12(f), in the event that (i) a determination is made pursuant to Section 10 of this Agreement that Indemnitee is not entitled to indemnification under this Agreement, (ii) advancement of Expenses is not timely made pursuant to Section 8 of this Agreement, (iii) no determination of entitlement to indemnification shall have been made pursuant to Section 10(a) of this Agreement within sixty (60) days after receipt by the Company of the request for indemnification for which a determination is to be made other than by Independent Counsel, (iv) payment of indemnification or reimbursement of expenses is not made pursuant to Section 5 or 6 or the last sentence of Section 10(a) of this Agreement within thirty (30) days after receipt by the Company of a written request therefor (including any invoices received by Indemnitee, which such invoices may be redacted as necessary to avoid the waiver of any privilege accorded by applicable law) or (v) payment of indemnification pursuant to Section 3 or 4 of this Agreement is not made within thirty (30) days after a determination has been made that Indemnitee is entitled to indemnification, Indemnitee shall be entitled to an adjudication by the Delaware Court of his or her entitlement to such indemnification or advancement. Alternatively, Indemnitee, at his or her option, may seek an award in arbitration to be conducted by a single arbitrator pursuant to the Commercial Arbitration Rules of the American Arbitration Association. Indemnitee shall commence such proceeding seeking an adjudication or an award in arbitration within 180 days following the date on which Indemnitee first has the right to commence such proceeding pursuant to this Section 12(a); provided, however, that the foregoing time limitation shall not apply in respect of a proceeding brought by Indemnitee to enforce his or her rights under Section 5 of this Agreement. The Company shall not oppose Indemnitee’s right to seek any such adjudication or award in arbitration.

(b) In the event that a determination shall have been made pursuant to Section 10(a) of this Agreement that Indemnitee is not entitled to indemnification, any judicial proceeding or arbitration commenced pursuant to this Section 12 shall be conducted in all respects as a de novo trial, or arbitration, on the merits and Indemnitee shall not be prejudiced by reason of that adverse determination. In any judicial proceeding or arbitration commenced pursuant to this Section 12, the Company shall have the burden of proving Indemnitee is not entitled to indemnification or advancement, as the case may be.

(c) If a determination shall have been made pursuant to Section 10(a) of this Agreement that Indemnitee is entitled to indemnification, the Company shall be bound by such determination in any judicial proceeding or arbitration commenced pursuant to this Section 12, absent (i) a misstatement by Indemnitee of a material fact, or an omission of a material fact necessary to make Indemnitee’s statement not materially misleading, in connection with the request for indemnification or (ii) a prohibition of such indemnification under applicable law.

(d) The Company shall be precluded from asserting in any judicial proceeding or arbitration commenced pursuant to this Section 12 that the procedures and presumptions of this Agreement are not valid, binding and enforceable and shall stipulate in any such court or before any such arbitrator that the Company is bound by all the provisions of this Agreement.

(e) The Company shall indemnify Indemnitee to the fullest extent permitted by law against any and all Enforcement Expenses and, if requested by Indemnitee, shall (within thirty (30) days after receipt by the Company of a written request therefor) advance, to the extent not prohibited by law, such Enforcement Expenses to Indemnitee, which are incurred by Indemnitee in connection with any action brought by Indemnitee for indemnification or advancement from the Company under this Agreement or under any directors’ and officers’ liability insurance policies maintained by the Company in the suit for which indemnification or

11

advancement is being sought. Such written request for advancement shall include invoices received by Indemnitee in connection with such Enforcement Expenses but, in the case of invoices in connection with legal services, any references to legal work performed or to expenditures made that would cause Indemnitee to waive any privilege accorded by applicable law need not be included with the invoice.

(f) Notwithstanding anything in this Agreement to the contrary, no determination as to entitlement to indemnification under this Agreement shall be required to be made prior to the final disposition of the Proceeding, including any appeal therein.

Section 13. Non-exclusivity; Survival of Rights; Insurance; [Primacy of Indemnification;] Subrogation.

(a) The rights of indemnification and to receive advancement as provided by this Agreement shall not be deemed exclusive of any other rights to which Indemnitee may at any time be entitled under applicable law, the Charter, the Bylaws, any agreement, a vote of stockholders or a resolution of directors, or otherwise. No amendment, alteration or repeal of this Agreement or of any provision hereof shall limit or restrict any right of Indemnitee under this Agreement in respect of any action taken or omitted by such Indemnitee in his or her Corporate Status prior to such amendment, alteration or repeal. To the extent that a change in Delaware law, whether by statute or judicial decision, permits greater indemnification or advancement than would be afforded currently under the Charter, Bylaws and this Agreement, it is the intent of the parties hereto that Indemnitee shall enjoy by this Agreement the greater benefits so afforded by such change. No right or remedy herein conferred is intended to be exclusive of any other right or remedy, and every other right and remedy shall be cumulative and in addition to every other right and remedy given hereunder or now or hereafter existing at law or in equity or otherwise. The assertion or employment of any right or remedy hereunder, or otherwise, shall not prevent the concurrent assertion or employment of any other right or remedy.

(b) To the extent that the Company maintains an insurance policy or policies providing liability insurance for directors, managers, partners, officers, employees, agents or trustees of the Company or of any other Enterprise, Indemnitee shall be covered by such policy or policies in accordance with its or their terms to the maximum extent of the coverage available for any such director, manager, partner, officer, employee, agent or trustee under such policy or policies. If, at the time of the receipt of a notice of a claim pursuant to the terms hereof, the Company has director and officer liability insurance in effect, the Company shall give prompt notice of such claim to the insurers in accordance with the procedures set forth in the respective policies. The Company shall thereafter take all necessary or desirable action to cause such insurers to pay, on behalf of the Indemnitee, all amounts payable as a result of such Proceeding in accordance with the terms of such policies. Upon request of Indemnitee, the Company shall also promptly provide to Indemnitee: (i) copies of all of the Company’s potentially applicable directors’ and officers’ liability insurance policies, (ii) copies of such notices delivered to the applicable insurers and (iii) copies of all subsequent communications and correspondence between the Company and such insurers regarding the Proceeding.

12

(c) [The Company hereby acknowledges that Indemnitee has certain rights to indemnification, advancement of expenses and/or insurance provided by [Name of Fund/Sponsor] and certain of [its][their] affiliates (collectively, the “Fund Indemnitors”). The Company hereby agrees (i) that it is the indemnitor of first resort (i.e., its obligations to Indemnitee are primary and any obligation of the Fund Indemnitors to advance expenses or to provide indemnification for the same expenses or liabilities incurred by Indemnitee are secondary), (ii) that it shall be required to advance the full amount of expenses incurred by Indemnitee and shall be liable for the full amount of all Expenses, judgments, penalties, fines and amounts paid in settlement to the extent legally permitted and as required by the terms of this Agreement and the Charter and/or Bylaws (or any other agreement between the Company and Indemnitee), without regard to any rights Indemnitee may have against the Fund Indemnitors, and (iii) that it irrevocably waives, relinquishes and releases the Fund Indemnitors from any and all claims against the Fund Indemnitors for contribution, subrogation or any other recovery of any kind in respect thereof. The Company further agrees that no advancement or payment by the Fund Indemnitors on behalf of Indemnitee with respect to any claim for which Indemnitee has sought indemnification from the Company shall affect the foregoing and the Fund Indemnitors shall have a right of contribution and/or be subrogated to the extent of such advancement or payment to all of the rights of recovery of Indemnitee against the Company. The Company and Indemnitee agree that the Fund Indemnitors are express third party beneficiaries of the terms of this Section 13(c).]

(d) [Except as provided in paragraph (c) above,] [I/i]n the event of any payment under this Agreement, the Company shall be subrogated to the extent of such payment to all of the rights of recovery of Indemnitee [(other than against the Fund Indemnitors)], who shall execute all papers required and take all action necessary to secure such rights, including execution of such documents as are necessary to enable the Company to bring suit to enforce such rights.

(e) [Except as provided in paragraph (c) above,] [T/t]he Company’s obligation to provide indemnification or advancement hereunder to Indemnitee who is or was serving at the request of the Company as a director, manager, partner, officer, employee, agent or trustee of any other Enterprise shall be reduced by any amount Indemnitee has actually received as indemnification or advancement from such other Enterprise.

Section 14. Duration of Agreement. This Agreement shall continue until and terminate upon the later of: (a) ten (10) years after the date that Indemnitee shall have ceased to serve as a director of the Company or (b) one (1) year after the final termination of any Proceeding, including any appeal, then pending in respect of which Indemnitee is granted rights of indemnification or advancement hereunder and of any proceeding commenced by Indemnitee pursuant to Section 12 of this Agreement relating thereto. This Agreement shall be binding upon the Company and its successors and assigns and shall inure to the benefit of Indemnitee and his or her heirs, executors and administrators. The Company shall require and cause any successor (whether direct or indirect by purchase, merger, consolidation or otherwise) to all, substantially all or a substantial part, of the business and/or assets of the Company, by written agreement in form and substance satisfactory to Indemnitee, expressly to assume and agree to perform this Agreement in the same manner and to the same extent that the Company would be required to perform if no such succession had taken place.

13

Section 15. Severability. If any provision or provisions of this Agreement shall be held to be invalid, illegal or unenforceable for any reason whatsoever: (a) the validity, legality and enforceability of the remaining provisions of this Agreement (including, without limitation, each portion of any section of this Agreement containing any such provision held to be invalid, illegal or unenforceable, that is not itself invalid, illegal or unenforceable) shall not in any way be affected or impaired thereby and shall remain enforceable to the fullest extent permitted by law; (b) such provision or provisions shall be deemed reformed to the extent necessary to conform to applicable law and to give the maximum effect to the intent of the parties hereto; and (c) to the fullest extent possible, the provisions of this Agreement (including, without limitation, each portion of any section of this Agreement containing any such provision held to be invalid, illegal or unenforceable, that is not itself invalid, illegal or unenforceable) shall be construed so as to give effect to the intent manifested thereby.

Section 16. Enforcement.

(a) The Company expressly confirms and agrees that it has entered into this Agreement and assumed the obligations imposed on it hereby in order to induce Indemnitee to [serve or continue to serve] as a director of the Company, and the Company acknowledges that Indemnitee is relying upon this Agreement in serving as a director of the Company.

(b) This Agreement constitutes the entire agreement between the parties hereto with respect to the subject matter hereof and supersedes all prior agreements and understandings, oral, written and implied, between the parties hereto with respect to the subject matter hereof; provided, however, that this Agreement is a supplement to and in furtherance of the Charter, the Bylaws and applicable law, and shall not be deemed a substitute therefor, nor to diminish or abrogate any rights of Indemnitee thereunder.

Section 17. Modification and Waiver. No supplement, modification or amendment, or waiver of any provision, of this Agreement shall be binding unless executed in writing by the parties thereto. No waiver of any of the provisions of this Agreement shall be deemed or shall constitute a waiver of any other provisions of this Agreement nor shall any waiver constitute a continuing waiver. No supplement, modification or amendment of this Agreement or of any provision hereof shall limit or restrict any right of Indemnitee under this Agreement in respect of any action taken or omitted by such Indemnitee prior to such supplement, modification or amendment.

Section 18. Notice by Indemnitee. Indemnitee agrees promptly to notify the Company in writing upon being served with any summons, citation, subpoena, complaint, indictment, information or other document relating to any Proceeding or matter which may be subject to indemnification, reimbursement or advancement as provided hereunder. The failure of Indemnitee to so notify the Company or any delay in notification shall not relieve the Company of any obligation which it may have to Indemnitee under this Agreement or otherwise, unless, and then only to the extent that, the Company did not otherwise learn of the Proceeding and such delay is materially prejudicial to the Company’s ability to defend such Proceeding or matter; and, provided, further, that notice will be deemed to have been given without any action on the part of Indemnitee in the event the Company is a party to the same Proceeding.

14

Section 19. Notices. All notices, requests, demands and other communications under this Agreement shall be in writing and shall be deemed to have been duly given if (i) delivered by hand and receipted for by the party to whom said notice or other communication shall have been directed, (ii) mailed by certified or registered mail with postage prepaid, on the third business day after the date on which it is so mailed, (iii) mailed by reputable overnight courier and receipted for by the party to whom said notice or other communication shall have been directed or (iv) sent by facsimile transmission, with receipt of oral confirmation that such transmission has been received:

(a) If to Indemnitee, at such address as Indemnitee shall provide to the Company.

(b) If to the Company to:

One Kendall Square, Building 600-700

Suite 6-401

Cambridge, MA 02139

Attention: Chief Executive Officer

or to any other address as may have been furnished to Indemnitee by the Company.

Section 20. Contribution. To the fullest extent permissible under applicable law, if the indemnification provided for in this Agreement is unavailable to Indemnitee for any reason whatsoever, the Company, in lieu of indemnifying Indemnitee, shall contribute to the amount incurred by Indemnitee, whether for judgments, fines, penalties, excise taxes, amounts paid or to be paid in settlement and/or for Expenses, in connection with any Proceeding in such proportion as is deemed fair and reasonable in light of all of the circumstances in order to reflect (i) the relative benefits received by the Company and Indemnitee in connection with the event(s) and/or transaction(s) giving rise to such Proceeding; and/or (ii) the relative fault of the Company (and its directors, officers, employees and agents) and Indemnitee in connection with such event(s) and/or transactions.

Section 21. Internal Revenue Code Section 409A. The Company intends for this Agreement to comply with the Indemnification exception under Section 1.409A-1(b)(10) of the regulations promulgated under the Internal Revenue Code of 1986, as amended (the “Code”), which provides that indemnification of, or the purchase of an insurance policy providing for payments of, all or part of the expenses incurred or damages paid or payable by Indemnitee with respect to a bona fide claim against Indemnitee or the Company do not provide for a deferral of compensation, subject to Section 409A of the Code, where such claim is based on actions or failures to act by Indemnitee in his or her capacity as a service provider of the Company. The parties intend that this Agreement be interpreted and construed with such intent.

15

Section 22. Applicable Law and Consent to Jurisdiction. This Agreement and the legal relations among the parties shall be governed by, and construed and enforced in accordance with, the laws of the State of Delaware, without regard to its conflict of laws rules. Except with respect to any arbitration commenced by Indemnitee pursuant to Section 12(a) of this Agreement, the Company and Indemnitee hereby irrevocably and unconditionally (i) agree that any action or proceeding arising out of or in connection with this Agreement shall be brought only in the Delaware Court, and not in any other state or federal court in the United States of America or any court in any other country, (ii) consent to submit to the exclusive jurisdiction of the Delaware Court for purposes of any action or proceeding arising out of or in connection with this Agreement, (iii) consent to service of process at the address set forth in Section 19 of this Agreement with the same legal force and validity as if served upon such party personally within the State of Delaware, (iv) waive any objection to the laying of venue of any such action or proceeding in the Delaware Court and (v) waive, and agree not to plead or to make, any claim that any such action or proceeding brought in the Delaware Court has been brought in an improper or inconvenient forum.

Section 23. Headings. The headings of the paragraphs of this Agreement are inserted for convenience only and shall not be deemed to constitute part of this Agreement or to affect the construction thereof.

Section 24. Identical Counterparts. This Agreement may be executed in one or more counterparts, each of which shall for all purposes be deemed to be an original but all of which together shall constitute one and the same Agreement. Only one such counterpart signed by the party against whom enforceability is sought needs to be produced to evidence the existence of this Agreement.

Section 25. Monetary Damages Insufficient/Specific Enforcement. The Company and Indemnitee agree that a monetary remedy for breach of this Agreement may be inadequate, impracticable and difficult of proof, and further agree that such breach may cause Indemnitee irreparable harm. Accordingly, the parties hereto agree that Indemnitee may enforce this Agreement by seeking injunctive relief and/or specific performance hereof, without any necessity of showing actual damage or irreparable harm (having agreed that actual and irreparable harm will result in not forcing the Company to specifically perform its obligations pursuant to this Agreement) and that by seeking injunctive relief and/or specific performance, Indemnitee shall not be precluded from seeking or obtaining any other relief to which he may be entitled. The Company and Indemnitee further agree that Indemnitee shall be entitled to such specific performance and injunctive relief, including temporary restraining orders, preliminary injunctions and permanent injunctions, without the necessity of posting bonds or other undertaking in connection therewith. The Company acknowledges that in the absence of a waiver, a bond or undertaking may be required of Indemnitee by the Court, and the Company hereby waives any such requirement of a bond or undertaking.

[Remainder of Page Intentionally Left Blank]

16

IN WITNESS WHEREOF, the parties have caused this Agreement to be signed as of the day and year first above written.

Exhibit 10.8

KORRO BIO, INC.

2019 STOCK INCENTIVE PLAN

This 2019 Stock Incentive Plan is intended to promote the interests of Korro Bio, Inc., a Delaware corporation, by providing eligible persons in the Corporation’s employ or service with the opportunity to acquire a proprietary interest, or otherwise increase their proprietary interest, in the Corporation as an incentive for them to continue in such employ or service.

Awards under the Plan may consist of (A) options, (B) stock awards, and (C) restricted stock units.

A. The Plan shall be administered by the Board. However, any or all administrative functions otherwise exercisable by the Board may be delegated to the Committee. Members of the Committee shall serve for such period of time as the Board may determine and shall be subject to removal by the Board at any time. The Board may also at any time terminate the functions of the Committee and reassume all powers and authority previously delegated to the Committee.

B. The Plan Administrator shall have the authority to determine which eligible persons are to receive Awards, the time or times when those Awards are to be made, the number of shares of Common Stock to be covered by each such Award, the applicable exercise and/or vesting schedule, the exercise price or purchase price (if any) to be paid by the Participant, the status of a granted option as either an Incentive Option or a Non-Statutory Option, and the maximum term for which the option is to remain outstanding.

C. The Plan Administrator shall have the authority (subject to the provisions of the Plan) to establish such rules and regulations as it may deem appropriate for proper administration of the Plan and to make such determinations under, and issue such interpretations of, the Plan and any outstanding Awards thereunder as it may deem necessary or advisable. Decisions of the Plan Administrator shall be final and binding on all parties who have an interest in the Plan or any Award thereunder.

A. The persons eligible to participate in the Plan are as follows:

1. Employees;

2. non-employee members of the Board and the non-employee members of the board of directors of any Parent or Subsidiary; and

3. persons who are consultants or other independent advisors who provide services to the Corporation (or any Parent or Subsidiary).

A. The stock issuable under the Plan shall be shares of authorized but unissued or reacquired Common Stock. Subject to adjustment as provided in Section V.D, the maximum number of shares of Common Stock which may be issued over the term of the Plan shall not exceed 15,048,960 shares.

B. Shares of Common Stock subject to outstanding Awards shall be available for subsequent issuance under the Plan to the extent those Awards expire, terminate or are cancelled for any reason prior to the issuance of the underlying shares of Common Stock. Unvested shares issued under the Plan and subsequently forfeited to or repurchased by the Corporation, at a price per share not greater than the exercise or purchase price paid per share, pursuant to the Corporation’s repurchase rights under the Plan, shall be added back to the number of shares of Common Stock reserved for issuance under the Plan and shall be available for reissuance through one or more subsequent Awards under the Plan.

C. Subject to adjustment as provided in Section V.D, the maximum number of shares of Common Stock which may be issued under the Plan pursuant to Incentive Options shall not exceed 15,048,960 shares.

D. Should any change be made to the Common Stock by reason of any stock split, stock dividend, spin-off transaction, extraordinary distribution (whether in cash, securities or other property), recapitalization, combination of shares, exchange of shares or other similar transaction affecting the outstanding Common Stock without the Corporation’s receipt of consideration or in the event of a substantial reduction to the value of the outstanding shares of Common Stock by reason of a spin-off transaction or extraordinary distribution or in the event of any merger, consolidation, reincorporation, or other reorganization, then equitable adjustments shall be made to (i) the maximum number and/or class of securities issuable under the Plan, (ii) the number and/or class of securities and the exercise or purchase price per share in effect under each outstanding Award, (iii) the number and/or class of securities subject to forfeiture or the Corporation’s outstanding repurchase rights under the Plan and the repurchase price payable per share and (iv) the maximum number of shares of Common Stock that may be issued under the Plan pursuant to Incentive Options. In the event of a Change in Control, the provisions of Section XI shall apply. The adjustments shall be made by the Plan Administrator in such manner as the Plan Administrator deems appropriate, and those adjustments shall be final, binding and conclusive. In no event shall any such adjustments be made in connection with the conversion of one or more outstanding shares of the Corporation’s preferred stock into shares of Common Stock.

The Plan Administrator may grant options to eligible persons upon such terms as it deems appropriate. Each option shall be evidenced by an Award Agreement in the form approved by the Plan Administrator; provided, however, that each such agreement shall comply with the terms and conditions of the Plan.

A. Type of Options. Each option shall be designated in the Award Agreement as either an Incentive Option or a Non-Statutory Option. Incentive Options may only be granted to Employees.

B. Exercise Price.

1. The exercise price per share shall be fixed by the Plan Administrator but shall not be less than one hundred percent (100%) of the Fair Market Value per share of Common Stock on the option grant date; provided, however, if any Employee to whom an Incentive Option is granted is a 10% Stockholder, then the exercise price per share shall not be less than one hundred ten percent (110%) of the Fair Market Value per share of Common Stock on the option grant date.

2

2. The exercise price shall be payable in one or more of the following forms as determined by the Plan Administrator and specified in the Award Agreement:

(i) cash or check made payable to the Corporation;

(ii) a promissory note payable to the Corporation having such recourse, interest, security and repayment terms as the Plan Administrator deems appropriate after taking into account the tax and accounting consequences of permitting the use of a promissory note and subject to the applicable requirements of the Delaware General Corporation Law;

(iii) by having the Corporation withhold a number of shares of Common Stock otherwise deliverable pursuant to the exercise of the option with such withheld shares valued at Fair Market Value on the Exercise Date;

(iv) should the Common Stock be registered under Section 12 of the 1934 Act at the time the option is exercised, in shares of Common Stock valued at Fair Market Value on the Exercise Date and held for the period (if any) necessary to avoid a charge to the Corporation’s earnings for financial reporting purposes; or

(v) should the Common Stock be registered under Section 12 of the 1934 Act at the time the option is exercised and only to the extent the option is exercised for vested shares, through a special sale and remittance procedure pursuant to which the Participant shall concurrently provide irrevocable instructions (A) to a brokerage firm (with such brokerage firm reasonably satisfactory to the Corporation for purposes of administering such procedure in compliance with any applicable pre- clearance or pre-notification requirements) to effect the immediate sale of the purchased shares and remit to the Corporation, out of the sale proceeds available on the settlement date, sufficient funds to cover the aggregate exercise price payable for the purchased shares plus all applicable taxes required to be withheld by the Corporation by reason of such exercise and (B) to the Corporation to deliver the certificates (if any) for the purchased shares directly to such brokerage firm on the settlement date in order to complete the sale.

Except to the extent a sale and remittance procedure is utilized, payment of the exercise price for the purchased shares must be made on the Exercise Date.

3. The Plan Administrator shall have the discretion (exercisable at any time) to permit the exercise price of an outstanding option to be paid in one or more of the forms specified in Section VI.B.2.

C. Exercise and Term of Options. Each option shall be exercisable at such time or times, during such period and for such number of shares as shall be determined by the Plan Administrator. No option shall have a term in excess of ten (10) years measured from the option grant date. If any Employee to whom an Incentive Option is granted is a 10% Stockholder, then the option term shall not exceed five (5) years measured from the option grant date.

3

D. Effect of Termination of Service.

1. The following provisions shall govern the exercise of any options held by the Participant at the time of cessation of Service or death:

(i) Should the Participant cease to remain in Service for any reason other than death, Disability or Misconduct, then the Participant shall have a period of three (3) months from the date of such cessation of Service during which to exercise each outstanding option held by such Participant.

(ii) Should the Participant’s Service terminate by reason of Disability, then the Participant shall have a period of twelve (12) months from the date of such cessation of Service during which to exercise each outstanding option held by such Participant.

(iii) If the Participant dies while holding an outstanding option, then the personal representative of his or her estate or the person or persons to whom the option is transferred pursuant to the Participant’s will or the laws of inheritance or, if beneficiary designations are permitted and have been validly made, the Participant’s designated beneficiary or beneficiaries of that option shall have a period of twelve (12) months from the date of the Participant’s death during which to exercise such option.

(iv) Under no circumstances, however, shall any such option be exercisable after the specified expiration of the option term.

(v) During the applicable post-Service exercise period, the option may not be exercised in the aggregate for more than the number of vested shares for which the option is exercisable at the time of cessation of the Participant’s Service or death. No additional shares shall vest under the option following the Participant’s cessation of Service, except to the extent (if any) specifically authorized by the Plan Administrator in its sole discretion pursuant to an express written agreement with the Participant. Upon the expiration of the applicable exercise period or (if earlier) upon the expiration of the option term, the option shall terminate and cease to be outstanding.

(vi) Should the Participant’s Service be terminated for Misconduct or should the Participant otherwise engage in Misconduct while holding one or more outstanding options under the Plan, then all those options shall terminate immediately and cease to remain outstanding.

2. The Plan Administrator shall have the discretion, exercisable either at the time an option is granted or at any time while the option remains outstanding, to:

(i) extend the period of time for which the option is to remain exercisable following the Participant’s cessation of Service or death from the limited period otherwise in effect for that option to such greater period of time as the Plan Administrator shall deem appropriate, but in no event beyond the expiration of the option term, and/or

(ii) permit the option to be exercised, during the applicable post- Service exercise period, not only with respect to the number of vested shares of Common Stock for which such option is exercisable at the time of the Participant’s cessation of Service or death but also with respect to one or more additional installments in which the Participant would have vested under the option had the Participant continued in Service.

4

E. Unvested Shares. The Plan Administrator shall have the discretion to grant options which are exercisable for unvested shares of Common Stock. Should the Participant cease Service while holding such unvested shares, the Corporation shall have the right to repurchase any or all of those unvested shares at a price per share equal to the lower of (i) the exercise price paid per share or (ii) the Fair Market Value per share of Common Stock at the time of the Participant’s cessation of Service. The terms upon which such repurchase right shall be exercisable (including the period and procedure for exercise and the appropriate vesting schedule for the purchased shares) shall be established by the Plan Administrator and set forth in the document evidencing such repurchase right.

F. Stockholder Rights. The holder of an option shall have no stockholder rights with respect to the shares subject to the option until such person shall have exercised the option, paid the exercise price and become the recordholder of the purchased shares.

G. Limits on Incentive Options. The aggregate Fair Market Value of the shares of Common Stock (determined as of the respective date or dates of grant) for which one or more options granted to any Employee under the Plan (or any other option plan of the Corporation or any Parent or Subsidiary) may for the first time become exercisable as Incentive Options during any one (1) calendar year shall not exceed the sum of One Hundred Thousand Dollars ($100,000). To the extent the Employee holds two (2) or more such options which become exercisable for the first time in the same calendar year, the foregoing limitation on the exercisability of such options as Incentive Options shall be applied on the basis of the order in which such options are granted, except to the extent otherwise provided under applicable law or regulation.

H. Repricing Program. The Plan Administrator shall have the authority to effect, at any time and from time to time, with the consent of the affected option holders, the cancellation of any or all outstanding options under the Plan and to grant in substitution therefor new options covering the same or different number of shares of Common Stock but with an exercise price per share based on the Fair Market Value per share of Common Stock on the new option grant date.

The Plan Administrator may issue shares of Common Stock to eligible persons upon such terms as it deems appropriate. Each such stock issuance shall be evidenced by an Award Agreement in the form approved by the Plan Administrator; provided, however, that each such agreement shall comply with the terms and conditions of the Plan.

A. Consideration. Shares of Common Stock may be issued under the Plan for any of the following items of consideration which the Plan Administrator may deem appropriate in each individual instance:

1. cash or check made payable to the Corporation;

2. past services rendered to the Corporation (or any Parent or Subsidiary);

3. a promissory note payable to the Corporation having such recourse, interest, security and repayment terms as the Plan Administrator deems appropriate after taking into account the tax and accounting consequences of permitting the use of a promissory note and subject to the applicable requirements of the Delaware General Corporation Law; or

4. any other valid consideration under the Delaware General Corporation Law.

5

B. Vesting Provisions.

1. Shares of Common Stock issued under the Plan may, in the discretion of the Plan Administrator, be fully and immediately vested upon issuance or may vest in one or more installments over the Participant’s period of Service or upon attainment of specified performance objectives.

2. Any new, substituted or additional securities or other property (including money paid other than as a regular cash dividend) which the Participant may have the right to receive with respect to the Participant’s unvested shares of Common Stock by reason of any stock dividend, stock split, spin-off transaction, extraordinary distribution (whether in cash, securities or other property), recapitalization, reincorporation, combination of shares, exchange of shares or other similar change affecting the outstanding Common Stock as a class without the Corporation’s receipt of consideration shall be issued subject to (i) the same vesting requirements applicable to the Participant’s unvested shares of Common Stock and (ii) such escrow arrangements as the Plan Administrator shall deem appropriate.

3. Should the Participant cease to remain in Service while holding one or more unvested shares of Common Stock issued under the Plan or should the performance objectives not be attained with respect to one or more such unvested shares of Common Stock, then those shares shall be immediately surrendered to the Corporation for cancellation, and the Participant shall have no further stockholder rights with respect to those shares. To the extent the surrendered shares were previously issued to the Participant for consideration paid in cash or cash equivalent (including the Participant’s purchase- money indebtedness), the Corporation shall repay to the Participant the lower of (i) the cash consideration paid for the surrendered shares or (ii) the Fair Market Value of those shares at the time of the Participant’s cessation of Service and shall cancel the unpaid principal balance of any outstanding purchase-money note of the Participant attributable to such surrendered shares by the applicable clause (i) or (ii) amount.

4. The Plan Administrator may in its discretion waive the surrender and cancellation of one or more unvested shares of Common Stock (or other assets attributable thereto) which would otherwise occur upon the non-completion of the vesting schedule applicable to those shares. Such waiver shall result in the immediate vesting of the Participant’s interest in the shares of Common Stock as to which the waiver applies. Such waiver may be effected at any time, whether before or after the Participant’s cessation of Service or the attainment or non-attainment of the applicable performance objectives.

C. Stockholder Rights. The Participant shall have full stockholder rights with respect to any shares of Common Stock issued to the Participant under a stock award, whether or not the Participant’s interest in those shares is vested. Accordingly, the Participant shall have the right to vote such shares and to receive any regular cash dividends paid on such shares.

The Plan Administrator may grant restricted stock units to eligible persons which entitle the Participants to receive the shares underlying those awards upon vesting or upon the expiration of a designated time period following the vesting of those awards. Each Award of restricted stock units shall be evidenced by one or more Award Agreements in the form approved by the Plan Administrator; provided, however, that each such agreement shall comply with the terms and conditions of the Plan.

6

A. Vesting Provisions.

1. Restricted stock units may, in the discretion of the Plan Administrator, vest in one or more installments over the Participant’s period of Service or upon the attainment of specified performance objectives.

2. Outstanding restricted stock units shall automatically terminate, and no shares of Common Stock shall actually be issued in satisfaction of those Awards, if the performance goals or Service requirements established for those Awards are not attained or satisfied. The Plan Administrator, however, shall have the discretionary authority to issue vested shares of Common Stock under one or more outstanding Awards of restricted stock units as to which the designated performance goals or Service requirements have not been attained or satisfied.

B. Stockholder Rights. The Participant shall not have any stockholder rights with respect to the shares of Common Stock subject to a restricted stock unit Award until that Award vests and the shares of Common Stock are actually issued thereunder.

A. Except as provided below, Awards, together with the shares of Common Stock subject to the Awards, shall not be assignable or transferable other than by will or by the laws of inheritance following the Participant’s death.

B. However, a Non-Statutory Option, together with the underlying unexercised shares of Common Stock, may to the extent permitted by the Plan Administrator be assigned in whole or in part during the Participant’s lifetime by gift or pursuant to a domestic relations order to one or more of the Participant’s Family Members or to a trust established exclusively for the Participant and/or one or more such Family Members. The assigned portion may only be exercised by the person or persons who acquire a proprietary interest in the Non-Statutory Option pursuant to the assignment. The terms applicable to the assigned portion shall be the same as those in effect for the option immediately prior to such assignment and shall be set forth in such documents issued to the assignee as the Plan Administrator may deem appropriate.

C. Notwithstanding the foregoing, the Participant may also, to the extent permitted by the Plan Administrator and subject to applicable law, designate one or more Family Members as the beneficiary or beneficiaries of his or her outstanding Awards under the Plan, and those Awards shall, in accordance with such designation, automatically be transferred to such beneficiary or beneficiaries upon the Participant’s death while holding those Awards. Such beneficiary or beneficiaries shall take the transferred Awards subject to all the terms and conditions of the applicable agreement evidencing each such transferred Award.

D. Prior to the date the Corporation first becomes subject to the reporting requirements of Section 13 or 15(d) of the 1934 Act, outstanding options under the Plan, together with the shares of Common Stock subject to those options during the period prior to exercise, shall not be the subject of any short position, put equivalent position (as such term is defined in Rule 16a-1(h) under the 1934 Act) or call equivalent position (as such term is defined Rule 16a-1(b) of the 1934 Act).

E. Except as otherwise provided above, until the date the Corporation first becomes subject to the reporting requirements of Section 13 or 15(d) of the 1934 Act, outstanding options under the Plan, together with the shares of Common Stock subject to those options during the period prior to exercise, shall not be the subject of any pledge, gift, hypothecation or other transfer, other than pursuant to the Corporation’s repurchase rights or in connection with a Change in Control in which such options shall terminate and cease to be outstanding.

7

A. Until such time as the Common Stock is first registered under Section 12 of the 1934 Act, the Corporation shall have the right of first refusal with respect to any proposed disposition by the Participant (or any successor in interest) of any shares of Common Stock issued under the Plan. Such right of first refusal shall be exercisable in accordance with the terms established by the Plan Administrator and set forth in the document evidencing such right.

B. In connection with any underwritten public offering by the Corporation of its equity securities, the Participant (or any successor in interest) shall be subject to transferability and market stand-off restrictions with respect to any shares of Common Stock issued under the Plan in accordance with the terms established by the Plan Administrator and set forth in the document evidencing the issuance of such shares.

C. The Plan Administrator may require that a Participant (or any successor in interest) execute a stockholders’ agreement, with such terms as the Plan Administrator deems appropriate, with respect to any shares of Common Stock issued to the Participant pursuant to the Plan.

D. Unvested shares may, in the Plan Administrator’s discretion, be held in escrow by the Corporation until the Participant’s interest in such shares vests or may be issued directly to the Participant with restrictive legends on the certificates (if any) evidencing those unvested shares.

A. In the event of a Change in Control, each outstanding Award, as determined by the Plan Administrator in its sole discretion, may be (i) assumed by the successor corporation (or parent thereof), (ii) canceled and substituted with an Award granted by the successor corporation (or parent thereof), (iii) otherwise continued in full force and effect pursuant to the terms of the Change in Control transaction, or (iv) replaced with a cash retention program of the Corporation or any successor corporation which preserves the spread existing on the unvested shares subject to the Award at the time of the Change in Control (the excess of the Fair Market Value of those shares over the aggregate purchase price payable for such shares) and, subject to Section XI.C, provides for subsequent payout of that spread in accordance with the same exercise/vesting schedule applicable to those unvested Award shares, but only if such replacement cash program would not result in the treatment of the Award as an item of deferred compensation subject to Code Section 409A.

B. To the extent an outstanding Award is not assumed, substituted, continued or replaced in accordance with Section XI.A, such Award shall automatically vest in full (and any repurchase rights, if any, of the Corporation with respect to the unvested shares subject to that Award that become vested on such accelerated basis shall immediately terminate) immediately prior to the effective date of the Change in Control, unless the acceleration of such Award is subject to other limitations imposed by the Plan Administrator at the time of the grant of the Award. The Plan Administrator in its sole discretion shall have the authority to provide that to the extent any such Award, as so accelerated, remains unexercised and outstanding on the effective date of the Change in Control, such Award shall be cancelled and terminated and the holder of such Award shall become entitled to receive, upon consummation of the Change in Control and subject to Section XI.C, a lump sum cash payment in an amount equal to the product of (i) the number of shares of Common Stock subject to such Award and (ii) the excess of (a) the Fair Market Value per share of Common Stock on the date of the Change in Control over (b) the per share exercise price or purchase

8

price in effect for such Award. However, any such Award shall be subject to cancellation and termination, without cash payment or other consideration due the Award holder, if the Fair Market Value per share of Common Stock on the date of such Change in Control is less than the per share exercise price or purchase price in effect for such Award.

C. The Plan Administrator shall have the authority to provide that any escrow, holdback, earn-out or similar provisions in the definitive agreement effecting the Change in Control shall apply to any cash payment made pursuant to Section XI.A(iv) or Section XI.B to the same extent and in the same manner as such provisions apply to a holder of a share of Common Stock.

D. The portion of any Incentive Option accelerated in connection with a Change in Control shall remain exercisable as an Incentive Option only to the extent the applicable One Hundred Thousand Dollar ($100,000) limitation is not exceeded. To the extent such dollar limitation is exceeded, the accelerated portion of such option shall be exercisable as a Non-Statutory Option under the United States Federal tax laws.

E. The grant of Awards under the Plan shall in no way affect the right of the Corporation to adjust, reclassify, reorganize or otherwise change its capital or business structure or to merge, consolidate, dissolve, liquidate or sell or transfer all or any part of its business or assets.

A. The Plan shall become effective when adopted by the Board, but no option granted under the Plan may be exercised, and no shares shall be issued under the Plan, until the Plan is approved by the Corporation’s stockholders. If such stockholder approval is not obtained within twelve (12) months after the date of the Board’s adoption of the Plan, then all Awards previously granted under the Plan shall terminate and cease to be outstanding, and no further Awards shall be granted and no shares shall be issued under the Plan. Subject to such limitation, the Plan Administrator may grant Awards and issue shares under the Plan at any time after the effective date of the Plan and before the date fixed herein for termination of the Plan.

B. The Board shall have complete and exclusive power and authority to amend or modify the Plan in any or all respects. However, no such amendment or modification shall adversely affect the rights and obligations with respect to Awards at the time outstanding under the Plan unless the Participant consents to such amendment or modification. In addition, certain amendments may require stockholder approval pursuant to applicable laws and regulations.

C. Awards may be granted under the Plan which are in excess of the number of shares of Common Stock then available for issuance under the Plan, provided any excess shares actually issued shall be held in escrow until there is obtained stockholder approval of an amendment sufficiently increasing the number of shares of Common Stock available for issuance under the Plan. If such stockholder approval is not obtained within twelve (12) months after the date the first such excess Awards are made, then (i) any unexercised options and unvested restricted stock units granted on the basis of such excess shares shall terminate and cease to be outstanding and (ii) the Corporation shall promptly refund to the Participants the exercise price or purchase price paid for any excess shares issued under the Plan and held in escrow, together with interest (at the applicable Short Term Federal Rate) for the period the shares were held in escrow, and such shares shall thereupon be automatically cancelled and cease to be outstanding.

9

D. The Plan shall terminate upon the earliest of (i) the expiration of the ten (10)-year period measured from the date the Plan is adopted by the Board, (ii) the date on which all shares available for issuance under the Plan shall have been issued as vested shares or (iii) the termination of all outstanding Awards under the Plan in connection with a Change in Control. All Awards outstanding at the time of a clause (i) termination event shall continue to have full force and effect in accordance with the provisions of the documents evidencing those Awards.

A. Any cash proceeds received by the Corporation from the sale of shares of Common Stock under the Plan shall be used for general corporate purposes.

B. The Corporation’s obligation to deliver shares of Common Stock upon the exercise of any options granted under the Plan or upon the issuance or vesting of any shares issued under the Plan shall be subject to the satisfaction of all applicable tax withholding requirements.

C. The implementation of the Plan, the granting of any Awards under the Plan and the issuance of any shares of Common Stock under an Award shall be subject to the Corporation’s procurement of all approvals and permits required by regulatory authorities having jurisdiction over the Plan, the Awards granted under it and the shares of Common Stock issued pursuant to it.

D. Nothing in the Plan shall confer upon the Participant any right to continue in Service for any period of specific duration or interfere with or otherwise restrict in any way the rights of the Corporation (or any Parent or Subsidiary employing or retaining such person) or of the Participant, which rights are hereby expressly reserved by each, to terminate such person’s Service at any time for any reason, with or without cause.

The following definitions shall be in effect under the Plan:

A. Award shall mean an option, a stock award, or a restricted stock unit.

B. Award Agreement shall mean the agreement entered into by the Corporation and the Participant evidencing the Award.

C. Board shall mean the Corporation’s Board of Directors.

D. Change in Control shall have the meaning assigned to such term in the Award Agreement for the particular Award or in any other agreement incorporated by reference into the Award Agreement for purposes of defining such term, and in the absence of such a Change in Control definition shall be deemed to have occurred if: (i) any “person” (as such term is used in sections 13(d) and 14(d) of the 1934 Act) becomes a “beneficial owner” (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of securities of the Corporation representing more than 50% of the voting power of the then outstanding securities of the Corporation; provided that a Change of Control shall not be deemed to occur as a result of a change of ownership resulting from the death of a stockholder, a Public Offering of the Corporation’s common stock, or as a result of a transaction in which the Corporation becomes a subsidiary of another corporation and in which the stockholders of the Corporation, immediately prior to the transaction, will beneficially own, immediately after the transaction, shares entitling such stockholders to more than 50% of all votes to which all stockholders of the parent corporation would be entitled in the election of directors (without consideration of the rights of any class of stock to elect directors by a separate class vote); or (ii) the consummation of (1) a merger or consolidation of the Corporation with another corporation where the stockholders of the Corporation, immediately prior to the merger or consolidation, will not beneficially own, immediately after the merger or consolidation, shares entitling such stockholders

10

to more than 50% of all votes to which all stockholders of the surviving corporation would be entitled in the election of directors (without consideration of the rights of any class of stock to elect directors by a separate class vote), (2) a sale or other disposition of all or substantially all of the assets of the Corporation or (3) a liquidation or dissolution of the Corporation.

E. Code shall mean the Internal Revenue Code of 1986, as amended.

F. Committee shall mean a committee of one (1) or more Board members appointed by the Board to exercise one or more administrative functions under the Plan.

G. Common Stock shall mean the Corporation’s common stock.

H. Corporation shall mean Korro Bio, Inc., a Delaware corporation, and any successor corporation to all or substantially all of the assets or voting stock of Korro Bio, Inc.

I. Disability shall have the meaning assigned to such term in the Award Agreement for the particular Award or in any other agreement incorporated by reference into the Award Agreement for purposes of defining such term, or in the absence of such a definition shall mean the inability of the Participant to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment that is expected to result in death or has lasted or can be expected to last for a continuous period of twelve (12) months or more.

J. Employee shall mean an individual who is in the employ of the Corporation (or any Parent or Subsidiary), subject to the control and direction of the employer entity as to both the work to be performed and the manner and method of performance.

K. Exercise Date shall mean the date on which the Corporation shall have received written notice of an option exercise.

L. Fair Market Value per share of Common Stock on any relevant date shall be determined in accordance with the following provisions:

(i) If the Common Stock is at the time listed on a Stock Exchange, then the Fair Market Value shall be the closing selling price per share of Common Stock on the date in question on the Stock Exchange determined by the Plan Administrator to be the primary market for the Common Stock. If there is no closing selling price for the Common Stock on the date in question, then the Fair Market Value shall be the closing selling price on the last preceding date for which such quotation exists.

(ii) If the Common Stock is not at the time listed on any Stock Exchange, then the Fair Market Value shall be determined by the Plan Administrator through the reasonable application of a reasonable valuation method that takes into account the applicable valuation factors set forth in the Treasury Regulations issued under Section 409A of the Code; provided, however, that with respect to an Incentive Option, such Fair Market Value shall be determined in accordance with the standards of Section 422 of the Code and the applicable Treasury Regulations thereunder.

M. Family Member means, with respect to a particular Participant, any child, stepchild, grandchild, parent, stepparent, grandparent, spouse, former spouse, sibling, niece, nephew, mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law or sister-in-law.

N. Incentive Option shall mean an option which satisfies the requirements of Code Section 422.

11

O. Involuntary Termination shall have the meaning assigned to such term in the Award Agreement for the particular Award or in any other agreement incorporated by reference into the Award Agreement for purposes of defining such term, or in the absence of such an Involuntary Termination definition shall mean the termination of the Service of any individual which occurs by reason of:

(i) such individual’s involuntary dismissal or discharge by the Corporation for reasons other than Misconduct, or

(ii) such individual’s voluntary resignation following (A) a material and permanent reduction in such individual’s level of compensation (including base salary, fringe benefits and target bonus under any corporate-performance based bonus or incentive programs) other than a general reduction in compensation that affects all similarly situated Service providers of the Corporation in substantially the same proportions; (B) a permanent relocation of such individual’s principal place of employment by more than sixty (60) miles; (C) any material breach by the Corporation of any material provision of such individual’s employment agreement (if any) or any material provision of any other agreement between such individual and the Corporation; or (D) a material, adverse change in such individual’s authority, duties, or responsibilities (other than temporarily while such individual is physically or mentally incapacitated or as required by applicable law); provided, however, that the individual has provided written notice to the Corporation of the existence of the circumstances providing grounds for such involuntary resignation within thirty (30) calendar days of the initial existence of such grounds and the Corporation has had at least thirty (30) calendar days from the date on which such notice is provided to cure such circumstances. If that individual has not involuntarily resigned as set forth herein within sixty (60) calendar days after the occurrence of the applicable grounds, then such individual will be deemed to have waived the right to involuntary resignation with respect to that occurrence.

P. Misconduct shall have the meaning assigned to such term in the Award Agreement for the particular Award or in any other agreement incorporated by reference into the Award Agreement for purposes of defining such term, and in the absence of such a Misconduct definition shall mean an individual’s (i) failure to comply with any valid and legal directive of the Board that continues for thirty (30) calendar days after written notice from the Corporation; (ii) engagement in dishonesty, illegal conduct, or misconduct, which, in each case, materially harms or is reasonably likely to materially harm the Corporation or its affiliates; (iii) embezzlement, misappropriation, or fraud, whether or not related to such individual’s employment with the Corporation; (iv) conviction of or plea of guilty or nolo contendere to a crime that constitutes a felony (or state law equivalent) or a crime that constitutes a misdemeanor involving moral turpitude, if such felony or other crime is work-related, materially impairs such individual’s ability to perform services for the Corporation or results in material harm or is reasonably likely to cause material harm to the Corporation or its affiliates; (v) violation of a material policy of the Corporation; (vi) willful or grossly negligent unauthorized disclosure of confidential information or trade secrets; (vii) material breach of any material obligation under such individual’s employment agreement (if any) or any other written agreement between such individual and the Corporation; or (viii) material failure to comply with the Corporation’s written policies or rules, as they may be in effect from time to time. The foregoing definition shall not in any way preclude or restrict the right of the Corporation (or any Parent or Subsidiary) to discharge or dismiss any Participant or other person in the Service of the Corporation (or any Parent or Subsidiary) for any other acts or omissions, but such other acts or omissions shall not be deemed, for purposes of the Plan, to constitute grounds for termination for Misconduct.

Q. 1933 Act shall mean the Securities Act of 1933, as amended.

R. 1934 Act shall mean the Securities Exchange Act of 1934, as amended.

12

S. Non-Statutory Option shall mean an option not intended to satisfy the requirements of Code Section 422.

T. Parent shall mean any corporation (other than the Corporation) in an unbroken chain of corporations ending with the Corporation, provided each corporation in the unbroken chain (other than the Corporation) owns, at the time of the determination, stock possessing fifty percent (50%) or more of the total combined voting power of all classes of stock in one of the other corporations in such chain.

U. Participant shall mean any person to whom an Award is granted under the Plan.

V. Plan shall mean this 2019 Stock Incentive Plan.

W. Plan Administrator shall mean either the Board or the Committee acting in its capacity as administrator of the Plan.

X. Public Offering the provisions herein that refer to a “Public Offering” shall be effective, if at all, upon the initial registration of the Common Stock under Section 12(b) or 12(g) of the 1934 Act, and shall remain effective thereafter for so long as such Common Stock is so registered.

Y. Service shall mean the performance of services for the Corporation (or any Parent or Subsidiary, whether now existing or subsequently established) by a person in the capacity of an Employee, a non-employee member of the board of directors or a consultant or independent advisor, except to the extent otherwise specifically provided in the documents evidencing the Award. For purposes of the Plan, a Participant shall be deemed to cease Service immediately upon the occurrence of either of the following events: (i) the Participant no longer performs services in any of the foregoing capacities for the Corporation or any Parent or Subsidiary or (ii) the entity for which the Participant is performing such services ceases to remain a Parent or Subsidiary of the Corporation, even though the Participant may subsequently continue to perform services for that entity. Service shall not be deemed to cease during a period of military leave, sick leave or other personal leave approved by the Corporation; provided, however, that for a leave which exceeds three (3) months, Service shall be deemed, for purposes of determining the period within which any outstanding option held by a Participant may be exercised as an Incentive Option, to cease on the first day immediately following the expiration of such three (3)-month period, unless such Participant is provided with the right to return to Service following such leave either by statute or by written contract. Except to the extent otherwise required by law or expressly authorized by the Plan Administrator or by the Corporation’s written policy on leaves of absence, no Service credit shall be given for vesting purposes for any period the Participant is on a leave of absence.

Z. Stock Exchange shall mean the Nasdaq Stock Market, the New York Stock Exchange, or the NYSE American Stock Exchange.

AA. Subsidiary shall mean any corporation (other than the Corporation) in an unbroken chain of corporations beginning with the Corporation, provided each corporation (other than the last corporation) in the unbroken chain owns, at the time of the determination, stock possessing fifty percent (50%) or more of the total combined voting power of all classes of stock in one of the other corporations in such chain.

BB. 10% Stockholder shall mean the owner of stock (as determined under Code Section 424(d)) possessing more than ten percent (10%) of the total combined voting power of all classes of stock of the Corporation (or any Parent or Subsidiary).

13

KORRO BIO, INC.

FIRST AMENDMENT

TO THE

2019 STOCK INCENTIVE PLAN

This FIRST AMENDMENT (this “Amendment”) to the 2019 Stock Incentive Plan (the “Plan”), of Korro Bio, Inc., a Delaware corporation (the “Company”), is being adopted by the Board of Directors of the Company by action by unanimous written consent dated as of May 24, 2019, and by the stockholders of the Company, by written consent dated as of May 24, 2019, such amendment to be effective immediately upon approval by the stockholders. Sections V.A. and V.C. of the Plan are hereby amended and restated in their entirety as follows:

“A. The stock issuable under the Plan shall be shares of authorized but unissued or reacquired Common Stock. Subject to adjustment as provided in Section V.D., the maximum number of shares of Common Stock which may be issued over the term of the Plan shall not exceed 934,750 shares.”

“C. Subject to adjustment as provided in Section V.D., the maximum number of shares of Common Stock which may be issued under the Plan pursuant to Incentive Options shall not exceed 934,750 shares.”

Except to the extent amended hereby, all of the terms, provisions and conditions set forth in the Plan are hereby ratified and confirmed in all respects and shall remain in full force and effect. The Plan and this Amendment shall be read and construed together as a single instrument.

[End of Document]

KORRO BIO, INC.

SECOND AMENDMENT

TO THE

2019 STOCK INCENTIVE PLAN

This SECOND AMENDMENT (this “Amendment”) to the 2019 Stock Incentive Plan, as amended by that certain First Amendment to the 2019 Stock Incentive Plan, effective May 24, 2019 (as amended, the “Plan”), of Korro Bio, Inc., a Delaware corporation (the “Company”), is being adopted by the Board of Directors of the Company by action by unanimous written consent dated as of August 16, 2019, and by the stockholders of the Company, by written consent dated as of August 16, 2019, such amendment to be effective immediately upon approval by the stockholders. Sections V.A. and V.C. of the Plan are hereby amended and restated in their entirety as follows:

“A. The stock issuable under the Plan shall be shares of authorized but unissued or reacquired Common Stock. Subject to adjustment as provided in Section V.D., the maximum number of shares of Common Stock which may be issued over the term of the Plan shall not exceed 2,021,502 shares.”

“C. Subject to adjustment as provided in Section V.D., the maximum number of shares of Common Stock which may be issued under the Plan pursuant to Incentive Options shall not exceed 2,021,502 shares.”

Except to the extent amended hereby, all of the terms, provisions and conditions set forth in the Plan are hereby ratified and confirmed in all respects and shall remain in full force and effect. The Plan and this Amendment shall be read and construed together as a single instrument.

[End of Document]

KORRO BIO, INC.

Amendment No. 3 To

2019 Stock Incentive Plan

Korro Bio, Inc.’s 2019 Stock Incentive Plan (the “Plan”), pursuant to Section V. thereof, is hereby amended as follows:

Adopted by the Board of Directors: June 20, 2020

Adopted by the Stockholders: June 20, 2020

KORRO BIO, INC.

Amendment No. 4 To

2019 Stock Incentive Plan

Korro Bio, Inc.’s 2019 Stock Incentive Plan (the “Plan”), pursuant to Section V. thereof, is hereby amended as follows:

Adopted by the Board of Directors: October 22, 2020

Adopted by the Stockholders: October 30, 2020

KORRO BIO, INC.

Amendment No. 5 To

2019 Stock Incentive Plan

Korro Bio, Inc.’s 2019 Stock Incentive Plan (the “Plan”), pursuant to Section V. thereof, is hereby amended as follows:

Adopted by the Board of Directors: April 13, 2021

Adopted by the Stockholders: April 28, 2021

KORRO BIO, INC.

Amendment No. 6 to

2019 Stock Incentive Plan

Korro Bio, Inc.’s 2019 Stock Incentive Plan (the “Plan”), pursuant to Section V. thereof, is hereby amended as follows:

Adopted by the Board of Directors: November 8, 2021

Adopted by the Stockholders: November 8, 2021

KORRO BIO, INC.

Amendment No. 7 to

2019 Stock Incentive Plan

Korro Bio, Inc.’s 2019 Stock Incentive Plan (the “Plan”), pursuant to Section V. thereof, is hereby amended as follows:

Adopted by the Board of Directors: March 23, 2023

KORRO BIO, INC.

2019 STOCK INCENTIVE PLAN

STOCK OPTION AGREEMENT

THIS STOCK OPTION AGREEMENT (this “Agreement”) is between Korro Bio, Inc., a corporation organized under the laws of the State of Delaware (the “Corporation”), and the Participant identified in the table in Section 1 below (the “Participant”). Capitalized terms used herein without definition shall have the meaning ascribed to such terms in the Corporation’s 2019 Stock Incentive Plan, a copy of which is attached hereto as Exhibit A, as may be amended from time to time (the “Plan”)

1. Grant of Option. Pursuant and subject to the Plan, the Corporation grants to the Participant on the “Grant Date” identified in the table below, an option (the “Option”) to purchase from the Corporation all or any part of the total of the number of shares identified in the table below (the “Shares”) of the common stock, par value $0.001 per share, of the Corporation (the “Common Stock”), at the exercise price per share set out in the table below.

2. Character of Option. A portion of this Option is intended to be treated as an “incentive stock option” within the meaning of Section 422 of the Internal Revenue Code of 1986, as amended, and the number of Shares that is intended to qualify for such tax treatment is identified in the Participant’s account on the Plan’s online administration platform.

3. Expiration of Option. Unless earlier terminated pursuant to the following sentence, this Option shall expire at 5:00 p.m. EDT on the Expiration Date. This Option shall not be exercisable, in whole or in part, after its Expiration Date. If Service shall cease or the Participant shall die prior to the Expiration Date, the provisions of the Plan shall govern exercise of any portion of the Option held by the Participant at the time of cessation of Service or upon Participant’s death.

4. Vesting; Termination of Option; Right of First Refusal.

(a) Vesting. Subject to and in accordance with the terms of the Plan, this Option shall become exercisable (“vest”) as to 25% of the original number of Shares on the first anniversary of the Vesting Commencement Date and thereafter as to an additional 2.08333% of

the original number of Shares at the end of each successive one-month period (on the same calendar day as the Vesting Commencement Date) following the first anniversary of the Vesting Commencement Date until the fourth anniversary of the Vesting Commencement Date, in monthly installments of whole shares as nearly equal as practicable (in each such case, the date of each such vesting, a “Vesting Date”); provided that on each Vesting Date the Participant remains in Service. The “Vesting Commencement Date” shall be the date set forth in Section 1 above. The portion of the Shares subject to the Option that has vested hereunder is referred to herein as the “Vested Option”. No portion of this Option may be exercised until such portion becomes a Vested Option. Notwithstanding anything herein to the contrary, the Board or the Committee may, at any time and in its discretion in accordance with the provisions of the Plan, cause any portion of the Option that is unvested to become a Vested Option.

(b) Termination of Option. Except as set forth in this Agreement or the Plan, or in any other agreement between the Participant and the Corporation, if the Participant ceases to remain in Service for any reason before all of the Option vests, any unvested portion of the Option shall automatically terminate and shall be forfeited as of the date of Participant ceases to be in Service.

(c) Right of First Refusal. Until such time as the Common Stock is registered under Section 12 of the 1934 Act, the Corporation shall have a right of first refusal as is set forth in Section X.A of the Plan, and the Common Stock shall be subject to the other restrictions set forth in Section X of the Plan.

5. Issuance of Shares and Tax Withholding.

(a) Issuance of Shares. If the Participant shall exercise all or a portion of a Vested Option, the Corporation shall deliver thereafter a certificate for such Shares, or, in its discretion, shall make a notation of such issuance in the Corporation’s stock ledger.

(b) Tax Withholding. All obligations of the Corporation under this Agreement shall be subject to the rights of the Corporation as set forth in the Plan to withhold amounts required to be withheld for any taxes, if applicable. To the extent not withheld in accordance with the immediately preceding sentence, the Participant shall be required to pay to the Corporation, or make other arrangements satisfactory to the Employer to provide for the payment of, any federal, state, local or other taxes that the Employer is required to withhold with respect to the Option.

6. No Stockholder Rights. The Participant shall not have any of the rights and privileges of a stockholder with respect to shares of Common Stock, including voting or dividend or dividend equivalent rights, until such shares shall have vested and been exercised as set forth herein.

7. Grant Subject to Plan Provisions. This grant is made pursuant to the Plan, the terms of which are incorporated herein by reference, and in all respects shall be interpreted in accordance with the Plan. The grant of the Option is subject to the provisions of the Plan and to interpretations, regulations and determinations concerning the Plan established from time to time by the Committee in accordance with the provisions of the Plan, including, but not limited to, provisions pertaining to (a) rights and obligations with respect to withholding taxes, (b) the

registration, qualification or listing of the shares of Common Stock, (c) changes in capitalization of the Corporation and (d) other requirements of applicable law. The Committee shall have the authority to interpret and construe the Option pursuant to the terms of the Plan, and its decisions shall be conclusive as to any questions arising hereunder.

8. No Employment or Other Rights. The grant of this Option shall not confer upon the Participant any right to be retained by or in the employ or service of, or continued Service to, the Corporation or any affiliate of the Corporation and shall not interfere in any way with the right of the corporation to terminate Service at any time.

9. Assignment and Transfers. Except as the Committee may otherwise permit pursuant to the Plan, the rights and interests of the Participant under this Agreement may not be sold, assigned, encumbered or otherwise transferred except, in the event of the death of the Participant, by will or by the laws of descent and distribution. In the event of any attempt by the Participant to alienate, assign, pledge, hypothecate, or otherwise dispose of the Option or any right hereunder, except as provided for in this Agreement, or in the event of the levy or any attachment, execution or similar process upon the rights or interests hereby conferred, the Corporation may terminate the Option by notice to the Participant, and the Option and all rights hereunder shall thereupon become null and void. The rights and protections of the Corporation hereunder shall extend to any successors or assigns of the Corporation and to the Corporation’s parents, subsidiaries, and affiliates. This Agreement may be assigned by the Corporation without the Participant’s consent.

10. Lock-Up. If, in connection with any underwritten public offering of securities of the Corporation, the Corporation sends written notice to the Participant stating that the restrictions on transfer set forth in Section 10 are applicable to such underwritten public offering, the Participant shall not sell, make any short sale of, loan, grant any option for the purchase of, pledge or otherwise encumber, or otherwise dispose of, any shares of Common Stock or any Option during the one hundred eighty (180) day period (and which period may be extended as requested by the Corporation or an underwriter to accommodate regulatory restrictions on (a) the publication or other distribution of research and reports and (b) analyst recommendations and opinions, including, but not limited to, the restrictions contained in Financial Industry Regulatory Authority (FINRA) Rule 2711(f)(4) or the New York Stock Exchange (NYSE) Rule 472(f)(4), or any successor provisions or amendments thereto) commencing on the effective date of any registration statement relating to such underwritten public offering, unless the Corporation has granted its prior written consent to any such sale, short sale, loan, grant of option, pledge, other encumbrance or other disposition. The foregoing restrictions are intended and shall be construed so as to preclude the Participant from engaging in any hedging or other transaction that is designed to or reasonably could be expected to lead to or result in a sale or disposition of any shares of Common Stock during such period even if such shares of Common Stock are or would be disposed of by someone other than the Participant. Such prohibited hedging or other transactions would include, without limitation, any short sale (whether or not against the box) or any purchase, sale or grant of any right (including without limitation any put or call option) with respect to any shares of Common Stock or with respect to any security that includes, relates to, or derives any significant part of its value from any shares of Common Stock. Without limiting the generality and applicability of the foregoing provisions of this Section 10, if, in connection with any underwritten public offering of securities of the Corporation, the managing underwriter

of such offering requires that the Corporation’s then current directors and officers enter into a lock-up agreement, then (1) the Participant (regardless of whether or not the Participant has complied or complies with the provisions of clause (2) below) shall be bound be, and shall be deemed to have agreed to, the same lock-up terms as those which the Corporation’s directors and officers are required to adhere, and (2) at the request of the Corporation or such managing underwriter, the Participant shall execute and deliver a lock-up agreement in form and substance equivalent to that which is required to be executed by the Corporation’s then current directors and officers.

11. Applicable Law. The validity, construction, interpretation and effect of this Agreement shall be governed by and construed in accordance with the laws of the State of Delaware, without giving effect to the conflicts of laws provisions thereof.

12. No Advice Regarding Option. The Corporation is not providing any tax, legal or financial advice, nor is the Corporation making any recommendations regarding Participant’s grant of the Option or participation in the Plan, or his or her exercise of the Option and acquisition or sale of the underlying Common Stock. The Participant is hereby advised to consult with his or her own personal tax, legal and financial advisors regarding his or her participation in the Plan before taking any action related to the Option or the Plan.

[The remainder of this page is intentionally left blank.]

IN WITNESS WHEREOF, the undersigned parties have executed and accepted this Agreement and agreed to the terms and conditions herein. This Agreement may be executed by the parties by means of electronic acceptance through the Corporation’s online acceptance process.

KORRO BIO, INC.

2019 STOCK INCENTIVE PLAN

STOCK OPTION AGREEMENT

THIS STOCK OPTION AGREEMENT (this “Agreement”) is between Korro Bio, Inc., a corporation organized under the laws of the State of Delaware (the “Corporation”), and the Participant identified in the table in Section 1 below (the “Participant”). Capitalized terms used herein without definition shall have the meaning ascribed to such terms in the Corporation’s 2019 Stock Incentive Plan, a copy of which is attached hereto as Exhibit A, as may be amended from time to time (the “Plan”)

1. Grant of Option. Pursuant and subject to the Plan, the Corporation grants to the Participant on the “Grant Date” identified in the table below, an option (the “Option”) to purchase from the Corporation all or any part of the total of the number of shares identified in the table below (the “Shares”) of the common stock, par value $0.001 per share, of the Corporation (the “Common Stock”), at the exercise price per share set out in the table below.

2. Character of Option. This Option is intended to be treated as an “incentive stock option” within the meaning of Section 422 of the Internal Revenue Code of 1986, as amended.

3. Expiration of Option. Unless earlier terminated pursuant to the following sentence, this Option shall expire at 5:00 p.m. EDT on the Expiration Date. This Option shall not be exercisable, in whole or in part, after its Expiration Date. If Service shall cease or the Participant shall die prior to the Expiration Date, the provisions of the Plan shall govern exercise of any portion of the Option held by the Participant at the time of cessation of Service or upon Participant’s death.

4. Vesting; Termination of Option; Right of First Refusal.

(a) Vesting. Subject to and in accordance with the terms of the Plan, this Option shall become exercisable (“vest”) as to 25% of the original number of Shares on the first anniversary of the Vesting Commencement Date and thereafter as to an additional 2.08333% of the original number of Shares at the end of each successive one-month period (on the same calendar day as the Vesting Commencement Date) following the first anniversary of the Vesting

Commencement Date until the fourth anniversary of the Vesting Commencement Date, in monthly installments of whole shares as nearly equal as practicable (in each such case, the date of each such vesting, a “Vesting Date”); provided that on each Vesting Date the Participant remains in Service. The “Vesting Commencement Date” shall be the date set forth in Section 1 above. The portion of the Shares subject to the Option that has vested hereunder is referred to herein as the “Vested Option”. No portion of this Option may be exercised until such portion becomes a Vested Option. Notwithstanding anything herein to the contrary, the Board or the Committee may, at any time and in its discretion in accordance with the provisions of the Plan, cause any portion of the Option that is unvested to become a Vested Option.

(b) Termination of Option. Except as set forth in this Agreement or the Plan, or in any other agreement between the Participant and the Corporation, if the Participant ceases to remain in Service for any reason before all of the Option vests, any unvested portion of the Option shall automatically terminate and shall be forfeited as of the date of Participant ceases to be in Service.

(c) Right of First Refusal. Until such time as the Common Stock is registered under Section 12 of the 1934 Act, the Corporation shall have a right of first refusal as is set forth in Section X.A of the Plan, and the Common Stock shall be subject to the other restrictions set forth in Section X of the Plan.

5. Issuance of Shares and Tax Withholding.

(a) Issuance of Shares. If the Participant shall exercise all or a portion of a Vested Option, the Corporation shall deliver thereafter a certificate for such Shares, or, in its discretion, shall make a notation of such issuance in the Corporation’s stock ledger.

(b) Tax Withholding. All obligations of the Corporation under this Agreement shall be subject to the rights of the Corporation as set forth in the Plan to withhold amounts required to be withheld for any taxes, if applicable. To the extent not withheld in accordance with the immediately preceding sentence, the Participant shall be required to pay to the Corporation, or make other arrangements satisfactory to the Employer to provide for the payment of, any federal, state, local or other taxes that the Employer is required to withhold with respect to the Option.

6. No Stockholder Rights. The Participant shall not have any of the rights and privileges of a stockholder with respect to shares of Common Stock, including voting or dividend or dividend equivalent rights, until such shares shall have vested and been exercised as set forth herein.

7. Grant Subject to Plan Provisions. This grant is made pursuant to the Plan, the terms of which are incorporated herein by reference, and in all respects shall be interpreted in accordance with the Plan. The grant of the Option is subject to the provisions of the Plan and to interpretations, regulations and determinations concerning the Plan established from time to time by the Committee in accordance with the provisions of the Plan, including, but not limited to, provisions pertaining to (a) rights and obligations with respect to withholding taxes, (b) the registration, qualification or listing of the shares of Common Stock, (c) changes in capitalization of the Corporation and (d) other requirements of applicable law. The Committee shall have the authority to interpret and construe the Option pursuant to the terms of the Plan, and its decisions shall be conclusive as to any questions arising hereunder.

8. No Employment or Other Rights. The grant of this Option shall not confer upon the Participant any right to be retained by or in the employ or service of, or continued Service to, the Corporation or any affiliate of the Corporation and shall not interfere in any way with the right of the corporation to terminate Service at any time.

9. Assignment and Transfers. Except as the Committee may otherwise permit pursuant to the Plan, the rights and interests of the Participant under this Agreement may not be sold, assigned, encumbered or otherwise transferred except, in the event of the death of the Participant, by will or by the laws of descent and distribution. In the event of any attempt by the Participant to alienate, assign, pledge, hypothecate, or otherwise dispose of the Option or any right hereunder, except as provided for in this Agreement, or in the event of the levy or any attachment, execution or similar process upon the rights or interests hereby conferred, the Corporation may terminate the Option by notice to the Participant, and the Option and all rights hereunder shall thereupon become null and void. The rights and protections of the Corporation hereunder shall extend to any successors or assigns of the Corporation and to the Corporation’s parents, subsidiaries, and affiliates. This Agreement may be assigned by the Corporation without the Participant’s consent.

10. Lock-Up. If, in connection with any underwritten public offering of securities of the Corporation, the Corporation sends written notice to the Participant stating that the restrictions on transfer set forth in Section 10 are applicable to such underwritten public offering, the Participant shall not sell, make any short sale of, loan, grant any option for the purchase of, pledge or otherwise encumber, or otherwise dispose of, any shares of Common Stock or any Option during the one hundred eighty (180) day period (and which period may be extended as requested by the Corporation or an underwriter to accommodate regulatory restrictions on (a) the publication or other distribution of research and reports and (b) analyst recommendations and opinions, including, but not limited to, the restrictions contained in Financial Industry Regulatory Authority (FINRA) Rule 2711(f)(4) or the New York Stock Exchange (NYSE) Rule 472(f)(4), or any successor provisions or amendments thereto) commencing on the effective date of any registration statement relating to such underwritten public offering, unless the Corporation has granted its prior written consent to any such sale, short sale, loan, grant of option, pledge, other encumbrance or other disposition. The foregoing restrictions are intended and shall be construed so as to preclude the Participant from engaging in any hedging or other transaction that is designed to or reasonably could be expected to lead to or result in a sale or disposition of any shares of Common Stock during such period even if such shares of Common Stock are or would be disposed of by someone other than the Participant. Such prohibited hedging or other transactions would include, without limitation, any short sale (whether or not against the box) or any purchase, sale or grant of any right (including without limitation any put or call option) with respect to any shares of Common Stock or with respect to any security that includes, relates to, or derives any significant part of its value from any shares of Common Stock. Without limiting the generality and applicability of the foregoing provisions of this Section 10, if, in connection with any underwritten public offering of securities of the Corporation, the managing underwriter of such offering requires that the Corporation’s then current directors and officers enter into a lock-up agreement, then (1) the Participant (regardless of whether or not the Participant has

complied or complies with the provisions of clause (2) below) shall be bound be, and shall be deemed to have agreed to, the same lock-up terms as those which the Corporation’s directors and officers are required to adhere, and (2) at the request of the Corporation or such managing underwriter, the Participant shall execute and deliver a lock-up agreement in form and substance equivalent to that which is required to be executed by the Corporation’s then current directors and officers.

11. Applicable Law. The validity, construction, interpretation and effect of this Agreement shall be governed by and construed in accordance with the laws of the State of Delaware, without giving effect to the conflicts of laws provisions thereof.

12. No Advice Regarding Option. The Corporation is not providing any tax, legal or financial advice, nor is the Corporation making any recommendations regarding Participant’s grant of the Option or participation in the Plan, or his or her exercise of the Option and acquisition or sale of the underlying Common Stock. The Participant is hereby advised to consult with his or her own personal tax, legal and financial advisors regarding his or her participation in the Plan before taking any action related to the Option or the Plan.

[The remainder of this page is intentionally left blank.]

IN WITNESS WHEREOF, the undersigned parties have executed and accepted this Agreement and agreed to the terms and conditions herein. This Agreement may be executed by the parties by means of electronic acceptance through the Corporation’s online acceptance process.

KORRO BIO, INC.

2019 STOCK INCENTIVE PLAN

NON-STATUTORY STOCK OPTION AGREEMENT

THIS NON-STATUTORY STOCK OPTION AGREEMENT (this “Agreement”) is between Korro Bio, Inc., a corporation organized under the laws of the State of Delaware (the “Corporation”), and the Participant identified in the table in Section 1 below (the “Participant”). Capitalized terms used herein without definition shall have the meaning ascribed to such terms in the Corporation’s 2019 Stock Incentive Plan, a copy of which is attached hereto as Exhibit A, as may be amended from time to time (the “Plan”)

1. Grant of Option. Pursuant and subject to the Plan, the Corporation grants to the Participant on the “Grant Date” identified in the table below, an option (the “Option”) to purchase from the Corporation all or any part of the total of the number of shares identified in the table below (the “Shares”) of the common stock, par value $0.001 per share, of the Corporation (the “Common Stock”), at the exercise price per share set out in the table below.

2. Character of Option. This Option is not intended to be treated as an “incentive stock option” within the meaning of Section 422 of the Internal Revenue Code of 1986, as amended.

3. Expiration of Option. Unless earlier terminated pursuant to the following sentence, this Option shall expire at 5:00 p.m. EDT on the Expiration Date. This Option shall not be exercisable, in whole or in part, after its Expiration Date. If Service shall cease or the Participant shall die prior to the Expiration Date, the provisions of the Plan shall govern exercise of any portion of the Option held by the Participant at the time of cessation of Service or upon Participant’s death.

4. Vesting; Termination of Option; Right of First Refusal.

(a) Vesting. Subject to and in accordance with the terms of the Plan, this Option shall become exercisable (“vest”) as to 25% of the original number of Shares on the first anniversary of the Vesting Commencement Date and thereafter as to an additional 2.08333% of the original number of Shares at the end of each successive one-month period (on the same

calendar day as the Vesting Commencement Date) following the first anniversary of the Vesting Commencement Date until the fourth anniversary of the Vesting Commencement Date, in monthly installments of whole shares as nearly equal as practicable (in each such case, the date of each such vesting, a “Vesting Date”); provided that on each Vesting Date the Participant remains in Service. The “Vesting Commencement Date” shall be the date set forth in Section 1 above. The portion of the Shares subject to the Option that has vested hereunder is referred to herein as the “Vested Option”. No portion of this Option may be exercised until such portion becomes a Vested Option. Notwithstanding anything herein to the contrary, the Board or the Committee may, at any time and in its discretion in accordance with the provisions of the Plan, cause any portion of the Option that is unvested to become a Vested Option.

(b) Termination of Option. Except as set forth in this Agreement or the Plan, or in any other agreement between the Participant and the Corporation, if the Participant ceases to remain in Service for any reason before all of the Option vests, any unvested portion of the Option shall automatically terminate and shall be forfeited as of the date of Participant ceases to be in Service.

(c) Right of First Refusal. Until such time as the Common Stock is registered under Section 12 of the 1934 Act, the Corporation shall have a right of first refusal as is set forth in Section X.A of the Plan, and the Common Stock shall be subject to the other restrictions set forth in Section X of the Plan.

5. Issuance of Shares and Tax Withholding.

(a) Issuance of Shares. If the Participant shall exercise all or a portion of a Vested Option, the Corporation shall deliver thereafter a certificate for such Shares, or, in its discretion, shall make a notation of such issuance in the Corporation’s stock ledger.

(b) Tax Withholding. All obligations of the Corporation under this Agreement shall be subject to the rights of the Corporation as set forth in the Plan to withhold amounts required to be withheld for any taxes, if applicable. To the extent not withheld in accordance with the immediately preceding sentence, the Participant shall be required to pay to the Corporation, or make other arrangements satisfactory to the Employer to provide for the payment of, any federal, state, local or other taxes that the Employer is required to withhold with respect to the Option.

6. No Stockholder Rights. The Participant shall not have any of the rights and privileges of a stockholder with respect to shares of Common Stock, including voting or dividend or dividend equivalent rights, until such shares shall have vested and been exercised as set forth herein.

7. Grant Subject to Plan Provisions. This grant is made pursuant to the Plan, the terms of which are incorporated herein by reference, and in all respects shall be interpreted in accordance with the Plan. The grant of the Option is subject to the provisions of the Plan and to interpretations, regulations and determinations concerning the Plan established from time to time by the Committee in accordance with the provisions of the Plan, including, but not limited to, provisions pertaining to (a) rights and obligations with respect to withholding taxes, (b) the registration, qualification or listing of the shares of Common Stock, (c) changes in capitalization of the Corporation and (d) other requirements of applicable law. The Committee shall have the authority to interpret and construe the Option pursuant to the terms of the Plan, and its decisions shall be conclusive as to any questions arising hereunder.

8. No Employment or Other Rights. The grant of this Option shall not confer upon the Participant any right to be retained by or in the employ or service of, or continued Service to, the Corporation or any affiliate of the Corporation and shall not interfere in any way with the right of the corporation to terminate Service at any time.

9. Assignment and Transfers. Except as the Committee may otherwise permit pursuant to the Plan, the rights and interests of the Participant under this Agreement may not be sold, assigned, encumbered or otherwise transferred except, in the event of the death of the Participant, by will or by the laws of descent and distribution. In the event of any attempt by the Participant to alienate, assign, pledge, hypothecate, or otherwise dispose of the Option or any right hereunder, except as provided for in this Agreement, or in the event of the levy or any attachment, execution or similar process upon the rights or interests hereby conferred, the Corporation may terminate the Option by notice to the Participant, and the Option and all rights hereunder shall thereupon become null and void. The rights and protections of the Corporation hereunder shall extend to any successors or assigns of the Corporation and to the Corporation’s parents, subsidiaries, and affiliates. This Agreement may be assigned by the Corporation without the Participant’s consent.

10. Lock-Up. If, in connection with any underwritten public offering of securities of the Corporation, the Corporation sends written notice to the Participant stating that the restrictions on transfer set forth in Section 10 are applicable to such underwritten public offering, the Participant shall not sell, make any short sale of, loan, grant any option for the purchase of, pledge or otherwise encumber, or otherwise dispose of, any shares of Common Stock or any Option during the one hundred eighty (180) day period (and which period may be extended as requested by the Corporation or an underwriter to accommodate regulatory restrictions on (a) the publication or other distribution of research and reports and (b) analyst recommendations and opinions, including, but not limited to, the restrictions contained in Financial Industry Regulatory Authority (FINRA) Rule 2711(f)(4) or the New York Stock Exchange (NYSE) Rule 472(f)(4), or any successor provisions or amendments thereto) commencing on the effective date of any registration statement relating to such underwritten public offering, unless the Corporation has granted its prior written consent to any such sale, short sale, loan, grant of option, pledge, other encumbrance or other disposition. The foregoing restrictions are intended and shall be construed so as to preclude the Participant from engaging in any hedging or other transaction that is designed to or reasonably could be expected to lead to or result in a sale or disposition of any shares of Common Stock during such period even if such shares of Common Stock are or would be disposed of by someone other than the Participant. Such prohibited hedging or other transactions would include, without limitation, any short sale (whether or not against the box) or any purchase, sale or grant of any right (including without limitation any put or call option) with respect to any shares of Common Stock or with respect to any security that includes, relates to, or derives any significant part of its value from any shares of Common Stock. Without limiting the generality and applicability of the foregoing provisions of this Section 10, if, in connection with any underwritten public offering of securities of the Corporation, the managing underwriter of such offering requires that the Corporation’s then current directors and officers enter into a

lock-up agreement, then (1) the Participant (regardless of whether or not the Participant has complied or complies with the provisions of clause (2) below) shall be bound be, and shall be deemed to have agreed to, the same lock-up terms as those which the Corporation’s directors and officers are required to adhere, and (2) at the request of the Corporation or such managing underwriter, the Participant shall execute and deliver a lock-up agreement in form and substance equivalent to that which is required to be executed by the Corporation’s then current directors and officers.

11. Applicable Law. The validity, construction, interpretation and effect of this Agreement shall be governed by and construed in accordance with the laws of the State of Delaware, without giving effect to the conflicts of laws provisions thereof.

12. No Advice Regarding Option. The Corporation is not providing any tax, legal or financial advice, nor is the Corporation making any recommendations regarding Participant’s grant of the Option or participation in the Plan, or his or her exercise of the Option and acquisition or sale of the underlying Common Stock. The Participant is hereby advised to consult with his or her own personal tax, legal and financial advisors regarding his or her participation in the Plan before taking any action related to the Option or the Plan.

[The remainder of this page is intentionally left blank.]

IN WITNESS WHEREOF, the undersigned parties have executed and accepted this Agreement and agreed to the terms and conditions herein. This Agreement may be executed by the parties by means of electronic acceptance through the Corporation’s online acceptance process.

KORRO BIO, INC.

RESTRICTED STOCK AWARD AGREEMENT

This RESTRICTED STOCK AWARD AGREEMENT, dated as of , 20 (this “Agreement”), is between KORRO BIO, INC., a Delaware corporation (the “Corporation”), and the undersigned Participant (the “Participant”). Capitalized terms used herein without definition shall have the meaning ascribed to such terms in the Corporation’s 2019 Stock Incentive Plan, a copy of which is attached hereto as Exhibit A, as may be amended from time to time (the “Plan”).

1. Grant of Restricted Stock Award. Pursuant to the Plan, the Corporation grants to the Participant a total of number of shares of Common Stock as is set forth on the signature page hereto, subject to the restrictions set forth below and in the Plan, including but not limited to Section V.D of the Plan (the “Shares”), at a purchase price per Share of $0. , for an aggregate purchase price of $ .00. This Award is granted as of the date first set forth above (the “Grant Date”).

2. Vesting; Cancellation of Shares; Right of First Refusal.

(a) Vesting. Subject to and in accordance with the terms of the Plan, the Shares shall vest 25% on the first anniversary of the Grant Date and 2.0833% thereafter in a series of monthly installments for 36 months beginning on the first month following the first anniversary of the Grant Date (on the same calendar date as the Grant Date) (in each such case, the date of each such vesting, a “Vesting Date”), provided that on each such Vesting Date the Participant remains in Service (all such Shares that have vested hereunder, “Vested Shares”). The vesting of the Shares shall be cumulative, but shall not exceed 100% of the Shares. If the vesting schedule set forth above in this Section 2(a) would produce fractional Shares, the number of Shares that vest shall be rounded down to the nearest whole Share and the fractional Shares shall be accumulated and vest on the last Vesting Date, subject to the Participant’s continued Service through the last Vesting Date. Notwithstanding anything herein to the contrary, the Board or the Committee may, at any time and in its discretion in accordance with the provisions of the Plan, cause any or all Shares that are unvested Shares to become Vested Shares. During the period before the Shares become Vested Shares, the Shares cannot be transferred, except as otherwise permitted pursuant to the terms of the Plan.

(b) Cancellation of Shares. Except as set forth in this Agreement or the Plan, or in any other agreement between the Participant and the Corporation, if the Participant ceases to remain in Service for any reason before all of the Shares vest, any unvested Shares shall automatically be surrendered to the Corporation for cancellation and the Participant shall no longer have any stockholder rights with respect to such surrendered and cancelled Shares. To the extent the surrendered Shares were previously issued to the Participant for consideration paid in cash or cash equivalents (including the Participant’s purchase money indebtedness), the Corporation shall repay to the Participant the lower of (i) the cash consideration paid for the surrendered Shares or (ii) the Fair Market Value of those Shares at the time of the Participant’s cessation of Service and shall cancel the unpaid principal balance of any outstanding purchase-money note of the Participant attributable to such surrendered Shares by the applicable clause (i) or (ii) amount.

(c) Right of First Refusal. Until such time as the Common Stock is registered under Section 12 of the 1934 Act, the Corporation shall have a right of first refusal as is set forth in Section X.A. of the Plan, and the Common Stock shall be subject to the other restrictions set forth in Section X of the Plan.

(d) Repurchase Right. In the event that the Participant ceases to remain in Service for any reason before all of the Shares vest, the Corporation shall, upon the date of such date the Participant ceases to remain in Service, have the right, but not the obligation, at any time for a period of one hundred and eighty (180) days from such date, to repurchase any or all of the Shares that have not yet become vested for $0.001 per share. Unless the Participant or the Participant’s executor is otherwise notified by the Corporation within such one hundred and eighty (180) day period, the Corporation shall automatically be deemed to have exercised its option to repurchase all of the Shares that have not yet become vested upon the date the Participant ceases to remain in Service, provided that the Corporation deliver to the Participant or the Participant’s executor a check in an amount equal to the aggregate repurchase price within such one hundred and eighty (180) day period. Upon delivery of the payment of the aggregate repurchase price, the Corporation shall become the legal and beneficial owner of the Shares being repurchased and all rights and interests therein or relating thereto, and the Corporation shall have the right to retain and transfer to its own name the number of Shares being repurchased by the Corporation.

3. Certificates; Taxes.

(a) Certificates. Unvested Shares may, in the Plan Administrator’s discretion, be held in escrow by the Corporation until the Shares vest or may be issued directly to the Participant with restrictive legends on the certificates (if any) evidencing those unvested Shares. Upon vesting of the Shares, the Corporation shall deliver thereafter a certificate for such shares of Common Stock, or, in its discretion, shall make a notation of such issuance in the Corporation’s stock ledger.

(b) Tax Withholding. All obligations of the Corporation under this Agreement shall be subject to the rights of the Corporation as set forth in the Plan to withhold amounts required to be withheld for any taxes, if applicable. To the extent not withheld in accordance with the immediately preceding sentence, the Participant shall be required to pay to the Corporation, or make other arrangements satisfactory to the Corporation to provide for the payment of, any federal, state, local or other taxes that the Corporation is required to withhold with respect to the Shares.

(c) Section 83(b) Election. The Participant hereby acknowledges that the Participant has been informed that, with respect to the Shares, the Participant may file an election with the Internal Revenue Service, within thirty (30) days following the Grant Date, electing pursuant to Section 83(b) of the Code to be taxed currently on any difference between the purchase price of the Shares and their Fair Market Value on the Grant Date. Absent such an election, taxable income will be measured and recognized by the Participant at the time or times at which the Shares vest. The Participant is strongly encouraged to seek the advice of his or her own tax consultants in connection with the issuance of the Shares and the advisability of filing of the election under Section 83(b) of the Code. A form of election under Section 83(b) is attached hereto as Exhibit B for reference.

THE PARTICIPANT ACKNOWLEDGES THAT IT IS NOT THE CORPORATION’S, BUT RATHER THE PARTICIPANT’S SOLE RESPONSIBILITY TO FILE THE ELECTION UNDER SECTION 83(b) TIMELY.

4. Stockholder Rights. The Participant shall have the rights and privileges of a stockholder with respect to Shares, including the right the vote the Shares and to receive any regular cash dividends on the Shares, whether or not the Shares have become Vested Shares. Any new, substituted or additional securities or other property (including money paid other than as a regular cash dividend) which the Participant may have the right to receive with respect to the Participant’s unvested Shares by reason of any stock dividend, stock split, spin-off transaction, extraordinary distribution (whether in cash, securities or other property), recapitalization, reincorporation, combination of shares, exchange of shares or other similar change affecting the outstanding Common Stock as a class without the Corporation’s receipt of consideration shall be issued subject to (a) the same vesting requirements applicable to the Participant’s unvested Shares and (b) such escrow arrangements as the Plan Administrator shall deem appropriate.

5. Grant Subject to Plan Provisions. This grant is made pursuant to the Plan, the terms of which are incorporated herein by reference, and in all respects shall be interpreted in accordance with the Plan. The grant and vesting of the Shares are subject to the provisions of the Plan and to interpretations, regulations and determinations concerning the Plan established from time to time by the Committee in accordance with the provisions of the Plan, including, but not limited to, provisions pertaining to (a) rights and obligations with respect to withholding taxes, (b) the registration, qualification or listing of the shares of Common Stock, (c) changes in capitalization of the Corporation and (d) other requirements of applicable law. The Committee shall have the authority to interpret and construe the Shares pursuant to the terms of the Plan, and its decisions shall be conclusive as to any questions arising hereunder.

6. No Employment or Other Rights. The grant of the Shares shall not confer upon the Participant any right to be retained by or in the employ or service of, or continued Service to, the Corporation or any affiliate of the Corporation and shall not interfere in any way with the right of the Corporation to terminate Service at any time.

7. Assignment and Transfers. Except as the Committee may otherwise permit pursuant to the Plan, the rights and interests of the Participant under this Agreement may not be sold, assigned, encumbered or otherwise transferred except, in the event of the death of the Participant, by will or by the laws of descent and distribution. In the event of any attempt by the Participant to alienate, assign, pledge, hypothecate, or otherwise dispose of the Shares or any right hereunder, except as provided for in this Agreement, or in the event of the levy or any attachment, execution or similar process upon the rights or interests hereby conferred, the Shares shall automatically be surrendered to the Corporation for cancellation and the Participant shall no longer have any stockholder rights with respect to such surrendered and cancelled Shares. The rights and protections of the Corporation hereunder shall extend to any successors or assigns of the Corporation and to the Corporation’s parents, subsidiaries, and affiliates. This Agreement may be assigned by the Corporation without the Participant’s consent.

8. Lock-Up. If, in connection with any underwritten public offering of securities of the Corporation, the Corporation sends written notice to the Participant stating that the restrictions on transfer set forth in this Section 8 are applicable to such unwritten public offering, the Participant shall not sell, make any short sale of, loan, grant any option for the purchase of, pledge or otherwise encumber, or otherwise dispose of, any shares of Common Stock (including the Shares) during the one hundred eighty (180) day period (and which period may be extended as requested by the Corporation or an underwriter to accommodate regulatory restrictions on (a) the publication or other distribution of research and reports and (b) analyst recommendations and opinions, including, but not limited to, the restrictions contained in Financial Industry Regulatory Authority (FINRA) Rule 2711(f)(4) or the New York Stock Exchange (NYSE) Rule 472(f)(4), or any successor provisions or amendments thereto) commencing on the effective date of any registration statement relating to such underwritten public offering, unless the Corporation has granted its prior written consent to any such sale, short sale, loan, grant of option, pledge, other encumbrance or other disposition. The foregoing restrictions are intended and shall be construed so as to preclude the Participant from engaging in any hedging or other transaction that is designed to or reasonably could be expected to lead to or result in a sale or disposition of any shares of Common Stock during such period even if such shares of Common Stock are or would be disposed of by someone other than the Participant. Such prohibited hedging or other transactions would include, without limitation, any short sale (whether or not against the box) or any purchase, sale or grant of any right (including without limitation any put or call option) with respect to any shares of Common Stock or with respect to any security that includes, relates to, or derives any significant part of its value from any shares of Common Stock. Without limiting the generality and applicability of the foregoing provisions of this Section 8, if, in connection with any underwritten public offering of securities of the Corporation, the managing underwriter of such offering requires that the Corporation’s then current directors and officers enter into a lock-up agreement, then (1) the Participant (regardless of whether or not the Participant has complied or complies with the provisions

of clause (2) below) shall be bound be, and shall be deemed to have agreed to, the same lock-up terms as those which the Corporation’s directors and officers are required to adhere, and (2) at the request of the Corporation or such managing underwriter, the Participant shall execute and deliver a lock-up agreement in form and substance equivalent to that which is required to be executed by the Corporation’s then current directors and officers.

9. Applicable Law. The validity, construction, interpretation and effect of this Agreement shall be governed by and construed in accordance with the laws of the State of Delaware, without giving effect to the conflicts of laws provisions thereof.

10. No Advice Regarding Shares. The Corporation is not providing any tax, legal or financial advice, nor is the Corporation making any recommendations regarding Participant’s award of Shares or participation in the Plan, or his or her acquisition or sale of the underlying Common Stock. The Participant is hereby advised to consult with his or her own personal tax, legal and financial advisors regarding his or her participation in the Plan before taking any action related to the Shares or the Plan.

[The remainder of this page is intentionally left blank.]

IN WITNESS WHEREOF, the parties have executed this Restricted Stock Award Agreement as a sealed instrument as of the date first above written.

Exhibit 10.9

KORRO BIO, INC.

2023 STOCK OPTION AND INCENTIVE PLAN

SECTION 1. GENERAL PURPOSE OF THE PLAN; DEFINITIONS

The name of the plan is the Korro Bio, Inc. 2023 Stock Option and Incentive Plan (as amended from time to time, the “Plan”). The purpose of the Plan is to encourage and enable the officers, employees, Non-Employee Directors and Consultants of Korro Bio, Inc. (the “Company”) and its Affiliates upon whose judgment, initiative and efforts the Company largely depends for the successful conduct of its business to acquire a proprietary interest in the Company. It is anticipated that providing such persons with a direct stake in the Company’s welfare will assure a closer identification of their interests with those of the Company and its stockholders, thereby stimulating their efforts on the Company’s behalf and strengthening their desire to remain with the Company.

The following terms shall be defined as set forth below:

“Act” means the U.S. Securities Act of 1933, as amended, and the rules and regulations thereunder.

“Administrator” means either the Board or the compensation committee of the Board or a similar committee performing the functions of the compensation committee and which is comprised of not less than two Non-Employee Directors who are independent.

“Affiliate” means, at the time of determination, any “parent” or “subsidiary” of the Company as such terms are defined in Rule 405 of the Act. The Board will have the authority to determine the time or times at which “parent” or “subsidiary” status is determined within the foregoing definition.

“Award” or “Awards,” except where referring to a particular category of grant under the Plan, shall include Incentive Stock Options, Non-Qualified Stock Options, Stock Appreciation Rights, Restricted Stock Units, Restricted Stock Awards, Unrestricted Stock Awards, Cash-Based Awards, and Dividend Equivalent Rights.

“Award Agreement” means a written or electronic document setting forth the terms and provisions applicable to an Award granted under the Plan. Each Award Agreement is subject to the terms and conditions of the Plan.

“Board” means the Board of Directors of the Company.

“Cash-Based Award” means an Award entitling the recipient to receive a cash-denominated payment.

“Closing Date” means the date of the closing of the transactions contemplated by that certain Agreement and Plan of Merger by and among Frequency Therapeutics, Inc., the Company and Frequency Merger Sub Inc., dated as of July 14, 2023.

“Code” means the U.S. Internal Revenue Code of 1986, as amended, and any successor Code, and related rules, regulations and interpretations.

“Consultant” means a consultant or adviser who provides bona fide services to the Company or an Affiliate as an independent contractor and who qualifies as a consultant or advisor under Instruction A.1.(a)(1) of Form S-8 under the Act.

“Dividend Equivalent Right” means an Award entitling the grantee to receive credits based on ordinary cash dividends that would have been paid on the shares of Stock specified in the Dividend Equivalent Right (or other award to which it relates) if such shares had been issued to and held by the grantee.

“Effective Date” means the date on which the Plan becomes effective as set forth in Section 19.

“Exchange Act” means the U.S. Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder.

“Fair Market Value” of the Stock on any given date means the fair market value of the Stock determined in good faith by the Administrator; provided, however, that if the Stock is listed on the National Association of Securities Dealers Automated Quotation System (“NASDAQ”), NASDAQ Global Market, The New York Stock Exchange or another national securities exchange or traded on any established market, the determination shall be made by reference to the closing price. If there is no closing price for such date, the determination shall be made by reference to the last date preceding such date for which there is a closing price.

“Incentive Stock Option” means any Stock Option designated and qualified as an “incentive stock option” as defined in Section 422 of the Code.

“Non-Employee Director” means a member of the Board who is not also an employee of the Company or any Subsidiary.

“Non-Qualified Stock Option” means any Stock Option that is not an Incentive Stock Option.

“Option” or “Stock Option” means any option to purchase shares of Stock granted pursuant to Section 5.

“Restricted Shares” means the shares of Stock underlying a Restricted Stock Award that remain subject to a risk of forfeiture or the Company’s right of repurchase.

“Restricted Stock Award” means an Award of Restricted Shares subject to such restrictions and conditions as the Administrator may determine at the time of grant.

“Restricted Stock Units” means an Award of stock units subject to such restrictions and conditions as the Administrator may determine at the time of grant.

2

“Sale Event” shall mean (i) the sale of all or substantially all of the assets of the Company on a consolidated basis to an unrelated person or entity, (ii) a merger, reorganization, statutory share exchange, consolidation, or similar transaction pursuant to which the holders of the Company’s outstanding voting power and outstanding stock immediately prior to such transaction do not own a majority of the outstanding voting power and outstanding stock or other equity interests of the resulting or successor entity (or its ultimate parent, if applicable) immediately upon completion of such transaction, (iii) the sale of all of the Stock of the Company to an unrelated person, entity or group thereof acting in concert, (iv) any other transaction in which the owners of the Company’s outstanding voting power immediately prior to such transaction do not own at least a majority of the outstanding voting power of the Company or any successor entity immediately upon completion of the transaction other than as a result of the acquisition of securities directly from the Company or (v) the approval by the stockholders of the Company of a complete liquidation or dissolution of the Company. Notwithstanding anything in the foregoing to the contrary, with respect to compensation (A) that is subject to Section 409A of the Code and (B) for which a Sale Event would accelerate the timing of payment thereunder, the term “Sale Event” shall mean an event that is both (I) a Sale Event (as defined above) and (II) a “change in control event” (within the meaning of Section 409A of the Code).

“Sale Price” means the value as determined by the Administrator of the consideration payable, or otherwise to be received by stockholders, per share of Stock pursuant to a Sale Event.

“Section 409A” means Section 409A of the Code and the regulations and other guidance promulgated thereunder.

“Service Relationship” means any relationship as an employee, Non-Employee Director or Consultant of the Company or any Affiliate. Unless as otherwise set forth in the Award Agreement, a Service Relationship shall be deemed to continue without interruption in the event a grantee’s status changes from full-time employee to part-time employee or a grantee’s status changes from employee to Consultant or Non-Employee Director or vice versa, provided that there is no interruption or other termination of Service Relationship in connection with the grantee’s change in capacity.

“Stock” means the Common Stock, par value $0.001 per share, of the Company, subject to adjustments pursuant to Section 3.

“Stock Appreciation Right” means an Award entitling the recipient to receive shares of Stock (or cash, to the extent explicitly provided for in the applicable Award Agreement) having a value equal to the excess of the Fair Market Value of the Stock on the date of exercise over the exercise price of the Stock Appreciation Right multiplied by the number of shares of Stock with respect to which the Stock Appreciation Right shall have been exercised.

“Subsidiary” means any corporation or other entity (other than the Company) in which the Company has at least a 50 percent interest, either directly or indirectly.

3

“Ten Percent Owner” means an employee who owns or is deemed to own (by reason of the attribution rules of Section 424(d) of the Code) more than 10 percent of the combined voting power of all classes of stock of the Company or any parent or subsidiary corporation.

“Unrestricted Stock Award” means an Award of shares of Stock free of any restrictions.

SECTION 2. ADMINISTRATION OF PLAN; ADMINISTRATOR AUTHORITY TO SELECT GRANTEES AND DETERMINE AWARDS

(a) Administration of Plan. The Plan shall be administered by the Administrator.

(b) Powers of Administrator. The Administrator shall have the power and authority to grant Awards consistent with the terms of the Plan, including the power and authority:

(i) to select the individuals to whom Awards may from time to time be granted;

(ii) to determine the time or times of grant, and the extent, if any, of Incentive Stock Options, Non-Qualified Stock Options, Stock Appreciation Rights, Restricted Stock Awards, Restricted Stock Units, Unrestricted Stock Awards, Cash-Based Awards, and Dividend Equivalent Rights, or any combination of the foregoing, granted to any one or more grantees;

(iii) to determine the number of shares of Stock to be covered by any Award;

(iv) to determine and modify from time to time the terms and conditions, including restrictions, not inconsistent with the terms of the Plan, of any Award, which terms and conditions may differ among individual Awards and grantees, and to approve the forms of Award Agreements;

(v) to accelerate at any time the exercisability or vesting of all or any portion of any Award;

(vi) subject to the provisions of Section 5(c) or 6(d), to extend at any time the period in which Stock Options or Stock Appreciation Rights, respectively, may be exercised; and

(vii) at any time to adopt, alter and repeal such rules, guidelines and practices for administration of the Plan and for its own acts and proceedings as it shall deem advisable; to interpret the terms and provisions of the Plan and any Award (including related written instruments); to make all determinations it deems advisable for the administration of the Plan; to decide all disputes arising in connection with the Plan; and to otherwise supervise the administration of the Plan.

All decisions and interpretations of the Administrator shall be binding on all persons, including the Company and Plan grantees.

4

(c) Delegation of Authority to Grant Awards. Subject to applicable law, the Administrator, in its discretion, may delegate to a committee consisting of one or more officers of the Company, including the Chief Executive Officer of the Company, all or part of the Administrator’s authority and duties with respect to the granting of Awards to individuals who are (i) not subject to the reporting and other provisions of Section 16 of the Exchange Act and (ii) not members of the delegated committee. Any such delegation by the Administrator shall include a limitation as to the amount of Stock underlying Awards that may be granted during the period of the delegation and shall contain guidelines as to the determination of the exercise price and the vesting criteria. The Administrator may revoke or amend the terms of a delegation at any time but such action shall not invalidate any prior actions of the Administrator’s delegate or delegates that were consistent with the terms of the Plan.

(d) Award Agreement. Awards under the Plan shall be evidenced by Award Agreements that set forth the terms, conditions and limitations for each Award which may include, without limitation, the term of an Award and the provisions applicable in the event the Service Relationship terminates.

(e) Indemnification. Neither the Board nor the Administrator, nor any member of either or any delegate thereof, shall be liable for any act, omission, interpretation, construction or determination made in good faith in connection with the Plan, and the members of the Board and the Administrator (and any delegate thereof) shall be entitled in all cases to indemnification and reimbursement by the Company in respect of any claim, loss, damage or expense (including, without limitation, reasonable attorneys’ fees) arising or resulting therefrom to the fullest extent permitted by law and/or under the Company’s articles or bylaws or any directors’ and officers’ liability insurance coverage which may be in effect from time to time and/or any indemnification agreement between such individual and the Company.

(f) Non-U.S. Award Recipients. Notwithstanding any provision of the Plan to the contrary, in order to comply with the laws in other countries in which the Company and its Affiliates operate or have employees or other individuals eligible for Awards, the Administrator, in its sole discretion, shall have the power and authority to: (i) determine which Affiliates shall be covered by the Plan; (ii) determine which individuals outside the United States are eligible to participate in the Plan; (iii) modify the terms and conditions of any Award granted to individuals outside the United States to comply with applicable laws; (iv) establish subplans and modify exercise procedures and other terms and procedures, to the extent the Administrator determines such actions to be necessary or advisable (and such subplans and/or modifications shall be incorporated into and made part of this Plan); provided, however, that no such subplans and/or modifications shall increase the share limitations contained in Section 3(a) hereof; and (v) take any action, before or after an Award is made, that the Administrator determines to be necessary or advisable to obtain approval or comply with any local governmental regulatory exemptions or approvals. Notwithstanding the foregoing, the Administrator may not take any actions hereunder, and no Awards shall be granted, that would violate the Exchange Act or any other applicable United States securities law, the Code, or any other applicable United States governing statute or law.

5

SECTION 3. STOCK ISSUABLE UNDER THE PLAN; MERGERS; SUBSTITUTION

(a) Stock Issuable. The maximum number of shares of Stock reserved and available for issuance under the Plan shall be shares (the “Initial Limit”), plus on January 1, 2024 and on each January 1 thereafter, the number of shares of Stock reserved and available for issuance under the Plan shall be cumulatively increased by five percent (5%) of the number of shares of Common Stock issued and outstanding on the immediately preceding December 31, or such lesser number of shares as approved by the Administrator, in all cases subject to adjustment as provided in this Section 3(c) (the “Annual Increase”). Subject to such overall limitation, the maximum aggregate number of shares of Stock that may be issued in the form of Incentive Stock Options shall not exceed the Initial Limit cumulatively increased on January 1, 2024 and on each January 1 thereafter by the lesser of the Annual Increase for such year or shares of Stock, subject in all cases to adjustment as provided in Section 3(c). For purposes of this Plan, the shares of Stock underlying any awards under the Plan and the shares of Common Stock of the Company underlying any awards under the Company’s 2019 Stock Incentive Plan, Frequency Therapeutics, Inc. 2014 Equity Incentive Plan or the Frequency Therapeutics, Inc. 2019 Incentive Award Plan, each as amended from time to time, that are forfeited, canceled, held back upon exercise of an Option or settlement of an Award to cover the exercise price or tax withholding, reacquired by the Company prior to vesting, satisfied without the issuance of Stock or otherwise terminated (other than by exercise) shall be added back to the shares of Stock available for issuance under the Plan and, to the extent permitted under Section 422 of the Code and the regulations promulgated thereunder, the shares of Stock that may be issued as Incentive Stock Options. In the event the Company repurchases shares of Stock on the open market, such shares shall not be added to the shares of Stock available for issuance under the Plan. Subject to such overall limitations, shares of Stock may be issued up to such maximum number pursuant to any type or types of Award. The shares available for issuance under the Plan may be authorized but unissued shares of Stock or shares of Stock reacquired by the Company. Awards that may be settled solely in cash shall not be counted against the share reserve, nor shall they reduce the shares of Stock authorized for grant to a grantee in any calendar year.

(b) Maximum Awards to Non-Employee Directors. Notwithstanding anything to the contrary in this Plan, the value of all Awards awarded under this Plan and all other cash compensation paid by the Company to any Non-Employee Director for services as a Non-Employee Director in any calendar year shall not exceed: (i) $1,000,000 in the first calendar year an individual becomes a Non-Employee Director and (ii) $750,000 in any other calendar year. For the purpose of this limitation, the value of any Award shall be its grant date fair value, as determined in accordance with ASC Topic 718 or successor provision but excluding the impact of estimated forfeitures related to service-based vesting provisions.

(c) Changes in Stock. Subject to Section 3(d) hereof, if, as a result of any reorganization, recapitalization, reclassification, stock dividend, extraordinary cash dividend, stock split, reverse stock split or other similar change in the Company’s capital stock, the outstanding shares of Stock are increased or decreased or are exchanged for a different number or kind of shares or other securities of the Company, or additional shares or new or different shares or other securities of the Company or other non-cash assets are distributed with respect to such shares of Stock or other securities, or, if, as a result of any merger or consolidation, sale of all or substantially all of the assets of the Company, the outstanding shares of Stock are converted into or exchanged for securities of the Company or any successor entity (or a parent or subsidiary thereof), the Administrator shall make an appropriate or proportionate adjustment in (i) the maximum number of shares reserved for issuance under the Plan, including the maximum number of shares that may be issued in the form of Incentive Stock Options, (ii) the number and kind of shares or other securities subject to any then outstanding Awards under the Plan, (iii) the

6

repurchase price, if any, per share subject to each outstanding Restricted Stock Award, and (iv) the exercise price for each share subject to any then outstanding Stock Options and Stock Appreciation Rights under the Plan, without changing the aggregate exercise price (i.e., the exercise price multiplied by the number of shares subject to Stock Options and Stock Appreciation Rights) as to which such Stock Options and Stock Appreciation Rights remain exercisable. The Administrator shall also make equitable or proportionate adjustments in the number of shares subject to outstanding Awards and the exercise price and the terms of outstanding Awards to take into consideration cash dividends paid other than in the ordinary course or any other extraordinary corporate event. The adjustment by the Administrator shall be final, binding and conclusive. No fractional shares of Stock shall be issued under the Plan resulting from any such adjustment, but the Administrator in its discretion may make a cash payment in lieu of fractional shares.

(d) Mergers and Other Transactions. In the case of and subject to the consummation of a Sale Event, the parties thereto may cause the assumption or continuation of Awards theretofore granted by the successor entity, or the substitution of such Awards with new Awards of the successor entity or parent thereof, with appropriate adjustment as to the number and kind of shares and, if appropriate, the per share exercise prices, as such parties shall agree. To the extent that the parties to such Sale Event do not provide for the assumption, continuation or substitution of Awards, upon the effective time of the Sale Event, the Plan and all outstanding Awards granted hereunder shall terminate. In such case, except as may be otherwise provided in the relevant Award Agreement, all Options and Stock Appreciation Rights with time-based vesting conditions or restrictions that are (i) not vested and/or exercisable immediately prior to the effective time of the Sale Event and (ii) held by grantees who have had a continuous Service Relationship with the Company or any of its Affiliates for at least one year prior to the effective time of the Sale Event shall become fully vested and exercisable as of the effective time of the Sale Event, all other Awards held by grantees (A) who have had a continuous Service Relationship with the Company or any of its Affiliates for at least one year prior to the effective time of the Sale Event and (B) that are subject solely to time-based vesting, conditions or restrictions shall become fully vested and nonforfeitable as of the effective time of the Sale Event, and all Awards with conditions and restrictions relating to the attainment of performance goals may become vested and nonforfeitable in connection with a Sale Event in the Administrator’s discretion or to the extent specified in the relevant Award Agreement. In the event of such termination, (i) the Company shall have the option (in its sole discretion) to make or provide for a payment, in cash or in kind, to the grantees holding Options and Stock Appreciation Rights, in exchange for the cancellation thereof, in an amount equal to the difference between (A) the Sale Price multiplied by the number of shares of Stock subject to outstanding Options and Stock Appreciation Rights (to the extent then exercisable at prices not in excess of the Sale Price) and (B) the aggregate exercise price of all such outstanding Options and Stock Appreciation Rights (provided that, in the case of an Option or Stock Appreciation Right with an exercise price equal to or greater than the Sale Price, such Option or Stock Appreciation Right shall be cancelled for no consideration); or (ii) each grantee shall be permitted, within a specified period of time prior to the consummation of the Sale Event as determined by the Administrator, to exercise all outstanding Options and Stock Appreciation Rights (to the extent then exercisable) held by such grantee. The Company shall also have the option (in its sole discretion) to make or provide for a payment, in cash or in kind, to the grantees holding other Awards in an amount equal to the Sale Price multiplied by the number of vested shares of Stock under such Awards.

7

SECTION 4. ELIGIBILITY

Grantees under the Plan will be such employees, Non-Employee Directors or Consultants of the Company and its Affiliates as are selected from time to time by the Administrator in its sole discretion; provided that Awards may not be granted to employees, Non-Employee Directors or Consultants who are providing services only to any “parent” of the Company, as such term is defined in Rule 405 of the Act, unless (i) the stock underlying the Awards is treated as “service recipient stock” under Section 409A or (ii) the Company has determined that such Awards are exempt from or otherwise comply with Section 409A.

SECTION 5. STOCK OPTIONS

(a) Award of Stock Options. The Administrator may grant Stock Options under the Plan. Any Stock Option granted under the Plan shall be in such form as the Administrator may from time to time approve.

Stock Options granted under the Plan may be either Incentive Stock Options or Non-Qualified Stock Options. Incentive Stock Options may be granted only to employees of the Company or any Subsidiary that is a “subsidiary corporation” within the meaning of Section 424(f) of the Code. To the extent that any Option does not qualify as an Incentive Stock Option, it shall be deemed a Non-Qualified Stock Option.

Stock Options granted pursuant to this Section 5 shall be subject to the following terms and conditions and shall contain such additional terms and conditions, not inconsistent with the terms of the Plan, as the Administrator shall deem desirable. If the Administrator so determines, Stock Options may be granted in lieu of cash compensation at the optionee’s election, subject to such terms and conditions as the Administrator may establish.

(b) Exercise Price. The exercise price per share for the Stock covered by a Stock Option granted pursuant to this Section 5 shall be determined by the Administrator at the time of grant but shall not be less than 100 percent of the Fair Market Value on the date of grant. In the case of an Incentive Stock Option that is granted to a Ten Percent Owner, the exercise price of such Incentive Stock Option shall be not less than 110 percent of the Fair Market Value on the date of grant. Notwithstanding the foregoing, Stock Options may be granted with an exercise price per share that is less than 100 percent of the Fair Market Value on the date of grant (i) pursuant to a transaction described in, and in a manner consistent with, Section 424(a) of the Code, (ii) to individuals who are not subject to U.S. income tax on the date of grant or (iii) if the Stock Option is otherwise compliant with Section 409A.

(c) Option Term. The term of each Stock Option shall be fixed by the Administrator, but no Stock Option shall be exercisable more than ten years after the date the Stock Option is granted. In the case of an Incentive Stock Option that is granted to a Ten Percent Owner, the term of such Stock Option shall be no more than five years from the date of grant.

8

(d) Exercisability; Rights of a Stockholder. Stock Options shall become exercisable at such time or times, whether or not in installments, as shall be determined by the Administrator at or after the date of grant. The Administrator may at any time accelerate the exercisability of all or any portion of any Stock Option. An optionee shall have the rights of a stockholder only as to shares acquired upon the exercise of a Stock Option and not as to unexercised Stock Options.

(e) Method of Exercise. Stock Options may be exercised in whole or in part, by giving written or electronic notice of exercise to the Company, specifying the number of shares to be purchased. Payment of the purchase price may be made by one or more of the following methods except to the extent otherwise provided in the Award Agreement:

(i) In cash, by certified or bank check or other instrument acceptable to the Administrator;

(ii) Through the delivery (or attestation to the ownership following such procedures as the Company may prescribe) of shares of Stock that are not then subject to restrictions under any Company plan. Such surrendered shares shall be valued at Fair Market Value on the exercise date;

(iii) By the optionee delivering to the Company a properly executed exercise notice together with irrevocable instructions to a broker to promptly deliver to the Company cash or a check payable and acceptable to the Company for the purchase price; provided that in the event the optionee chooses to pay the purchase price as so provided, the optionee and the broker shall comply with such procedures and enter into such agreements of indemnity and other agreements as the Company shall prescribe as a condition of such payment procedure; or

(iv) With respect to Stock Options that are not Incentive Stock Options, by a “net exercise” arrangement pursuant to which the Company will reduce the number of shares of Stock issuable upon exercise by the largest whole number of shares with a Fair Market Value that does not exceed the aggregate exercise price.

Payment instruments will be received subject to collection. The transfer to the optionee on the records of the Company or of the transfer agent of the shares of Stock to be purchased pursuant to the exercise of a Stock Option will be contingent upon receipt from the optionee (or a purchaser acting in his stead in accordance with the provisions of the Stock Option) by the Company of the full purchase price for such shares and the fulfillment of any other requirements contained in the Award Agreement or applicable provisions of laws (including the satisfaction of any taxes that the Company or an Affiliate is obligated to withhold with respect to the optionee). In the event an optionee chooses to pay the purchase price by previously-owned shares of Stock through the attestation method, the number of shares of Stock transferred to the optionee upon the exercise of the Stock Option shall be net of the number of attested shares. In the event that the Company establishes, for itself or using the services of a third party, an automated system for the exercise of Stock Options, such as a system using an internet website or interactive voice response, then the paperless exercise of Stock Options may be permitted through the use of such an automated system.

9

(f) Annual Limit on Incentive Stock Options. To the extent required for “incentive stock option” treatment under Section 422 of the Code, the aggregate Fair Market Value (determined as of the time of grant) of the shares of Stock with respect to which Incentive Stock Options granted under this Plan and any other plan of the Company or its parent and subsidiary corporations become exercisable for the first time by an optionee during any calendar year shall not exceed $100,000. To the extent that any Stock Option exceeds this limit, it shall constitute a Non-Qualified Stock Option. For purposes of this Section 5(f), Incentive Stock Options will be taken into account in the order in which they were granted, the Fair Market Value of the shares of Stock will be determined as of the time the Stock Option with respect to such shares of Stock is granted, and calculation will be performed in accordance with Section 422 of the Code and Treasury Regulations promulgated thereunder.

SECTION 6. STOCK APPRECIATION RIGHTS

(a) Award of Stock Appreciation Rights. The Administrator may grant Stock Appreciation Rights under the Plan. A Stock Appreciation Right is an Award entitling the recipient to receive shares of Stock (or cash, to the extent explicitly provided for in the applicable Award Agreement) having a value equal to the excess of the Fair Market Value of a share of Stock on the date of exercise over the exercise price of the Stock Appreciation Right multiplied by the number of shares of Stock with respect to which the Stock Appreciation Right shall have been exercised.

(b) Exercise Price of Stock Appreciation Rights. The exercise price of a Stock Appreciation Right shall not be less than 100 percent of the Fair Market Value of the Stock on the date of grant. Notwithstanding the foregoing, Stock Appreciation Rights may be granted with an exercise price per share that is less than 100 percent of the Fair Market Value on the date of grant (i) pursuant to a transaction described in, and in a manner consistent with, Section 424(a) of the Code, (ii) to individuals who are not subject to U.S. income tax on the date of grant, or (iii) if the Stock Appreciation Right is otherwise compliant with Section 409A.

(c) Grant and Exercise of Stock Appreciation Rights. Stock Appreciation Rights may be granted by the Administrator independently of any Stock Option granted pursuant to Section 5 of the Plan.

(d) Terms and Conditions of Stock Appreciation Rights. Stock Appreciation Rights shall be subject to such terms and conditions as shall be determined on the date of grant by the Administrator. The term of a Stock Appreciation Right may not exceed ten years. The terms and conditions of each such Award shall be determined by the Administrator, and such terms and conditions may differ among individual Awards and grantees.

SECTION 7. RESTRICTED STOCK AWARDS

(a) Nature of Restricted Stock Awards. The Administrator may grant Restricted Stock Awards under the Plan. A Restricted Stock Award is any Award of Restricted Shares subject to such restrictions and conditions as the Administrator may determine at the time of grant. Conditions may be based on continuing employment (or other Service Relationship) and/or achievement of pre-established performance goals and objectives.

10

(b) Rights as a Stockholder. Upon the grant of the Restricted Stock Award and payment of any applicable purchase price, a grantee shall have the rights of a stockholder with respect to the voting of the Restricted Shares and receipt of dividends; provided that if the lapse of restrictions with respect to the Restricted Stock Award is tied to the attainment of vesting conditions, any dividends paid by the Company shall accrue and shall not be paid to the grantee until and to the extent the vesting conditions are met with respect to the Restricted Stock Award. Unless the Administrator shall otherwise determine, (i) uncertificated Restricted Shares shall be accompanied by a notation on the records of the Company or the transfer agent to the effect that they are subject to forfeiture until such Restricted Shares are vested as provided in Section 7(d) below, and (ii) certificated Restricted Shares shall remain in the possession of the Company until such Restricted Shares are vested as provided in Section 7(d) below, and the grantee shall be required, as a condition of the grant, to deliver to the Company such instruments of transfer as the Administrator may prescribe.

(c) Restrictions. Restricted Shares may not be sold, assigned, transferred, pledged or otherwise encumbered or disposed of except as specifically provided herein or in the Restricted Stock Award Agreement. Except as may otherwise be provided by the Administrator either in the Award Agreement or, subject to Section 16 below, in writing after the Award is issued, if a grantee’s employment (or other Service Relationship) with the Company and its Affiliates terminates for any reason, any Restricted Shares that have not vested at the time of termination shall automatically and without any requirement of notice to such grantee from or other action by or on behalf of, the Company be deemed to have been reacquired by the Company at its original purchase price (if any) from such grantee or such grantee’s legal representative simultaneously with such termination of employment (or other Service Relationship), and thereafter shall cease to represent any ownership of the Company by the grantee or rights of the grantee as a stockholder. Following such deemed reacquisition of Restricted Shares that are represented by physical certificates, a grantee shall surrender such certificates to the Company upon request without consideration.

(d) Vesting of Restricted Shares. The Administrator at the time of grant shall specify the date or dates and/or the attainment of pre-established performance goals, objectives and other conditions on which the non-transferability of the Restricted Shares and the Company’s right of repurchase or forfeiture shall lapse. Subsequent to such date or dates and/or the attainment of such pre-established performance goals, objectives and other conditions, the shares on which all restrictions have lapsed shall no longer be Restricted Shares and shall be deemed “vested.”

SECTION 8. RESTRICTED STOCK UNITS

(a) Nature of Restricted Stock Units. The Administrator may grant Restricted Stock Units under the Plan. A Restricted Stock Unit is an Award of stock units that may be settled in shares of Stock (or cash, to the extent explicitly provided for in the Award Agreement) upon the satisfaction of such restrictions and conditions at the time of grant. Conditions may be based on continuing employment (or other Service Relationship) and/or achievement of pre-established performance goals and objectives. The terms and conditions of each such Award shall be determined by the Administrator, and such terms and conditions may differ among individual Awards and grantees. Restricted Stock Units with deferred settlement dates are subject to Section 409A and shall contain such additional terms and conditions as the Administrator shall determine in its sole discretion in order to comply with the requirements of Section 409A.

11

(b) Election to Receive Restricted Stock Units in Lieu of Compensation. The Administrator may, in its sole discretion, permit a grantee to elect to receive a portion of future cash compensation otherwise due to such grantee in the form of an award of Restricted Stock Units. Any such election shall be made in writing and shall be delivered to the Company no later than the date specified by the Administrator and in accordance with Section 409A and such other rules and procedures established by the Administrator. Any such future cash compensation that the grantee elects to defer shall be converted to a fixed number of Restricted Stock Units based on the Fair Market Value of Stock on the date the compensation would otherwise have been paid to the grantee if such payment had not been deferred as provided herein. The Administrator shall have the sole right to determine whether and under what circumstances to permit such elections and to impose such limitations and other terms and conditions thereon as the Administrator deems appropriate. Any Restricted Stock Units that are elected to be received in lieu of cash compensation shall be fully vested, unless otherwise provided in the Award Agreement.

(c) Rights as a Stockholder. A grantee shall have the rights as a stockholder only as to shares of Stock acquired by the grantee upon settlement of Restricted Stock Units; provided, however, that the grantee may be credited with Dividend Equivalent Rights with respect to the stock units underlying his or her Restricted Stock Units, subject to the provisions of Section 11 and such terms and conditions as the Administrator may determine.

(d) Termination. Except as may otherwise be provided by the Administrator either in the Award Agreement or, subject to Section 16 below, in writing after the Award is issued, a grantee’s right in all Restricted Stock Units that have not vested shall automatically terminate upon the grantee’s termination of employment (or cessation of Service Relationship) with the Company and its Affiliates for any reason.

SECTION 9. UNRESTRICTED STOCK AWARDS

Grant or Sale of Unrestricted Stock. The Administrator may grant (or sell at par value or such higher purchase price determined by the Administrator) an Unrestricted Stock Award under the Plan. An Unrestricted Stock Award is an Award pursuant to which the grantee may receive shares of Stock free of any restrictions under the Plan. Unrestricted Stock Awards may be granted in respect of past services or other valid consideration, or in lieu of cash compensation due to such grantee.

SECTION 10. CASH-BASED AWARDS

Grant of Cash-Based Awards. The Administrator may grant Cash-Based Awards under the Plan. A Cash-Based Award is an Award that entitles the grantee to a payment in cash upon the attainment of specified performance goals, including continued employment (or other Service Relationship). The Administrator shall determine the maximum duration of the Cash-Based Award, the amount of cash to which the Cash-Based Award pertains, the conditions upon which the Cash-Based Award shall become vested or payable, and such other provisions as the Administrator shall determine. Each Cash-Based Award shall specify a cash-denominated payment amount, formula or payment ranges as determined by the Administrator. Payment, if any, with respect to a Cash-Based Award shall be made in accordance with the terms of the Award and may be made in cash.

12

SECTION 11. DIVIDEND EQUIVALENT RIGHTS

(a) Dividend Equivalent Rights. The Administrator may grant Dividend Equivalent Rights under the Plan. A Dividend Equivalent Right is an Award entitling the grantee to receive credits based on cash dividends that would have been paid on the shares of Stock specified in the Dividend Equivalent Right (or other Award to which it relates) if such shares had been issued to the grantee. A Dividend Equivalent Right may be granted hereunder to any grantee as a component of an award of Restricted Stock Units or as a freestanding award. The terms and conditions of Dividend Equivalent Rights shall be specified in the Award Agreement. Dividend equivalents credited to the holder of a Dividend Equivalent Right may be paid currently or may be deemed to be reinvested in additional shares of Stock, which may thereafter accrue additional equivalents. Any such reinvestment shall be at Fair Market Value on the date of reinvestment or such other price as may then apply under a dividend reinvestment plan sponsored by the Company, if any. Dividend Equivalent Rights may be settled in cash or shares of Stock or a combination thereof, in a single installment or installments. A Dividend Equivalent Right granted as a component of an Award of Restricted Stock Units shall provide that such Dividend Equivalent Right shall be settled only upon settlement or payment of, or lapse of restrictions on, such other Award, and that such Dividend Equivalent Right shall expire or be forfeited or annulled under the same conditions as such other Award.

(b) Termination. Except as may otherwise be provided by the Administrator either in the Award Agreement or, subject to Section 16 below, in writing after the Award is issued, a grantee’s rights in all Dividend Equivalent Rights shall automatically terminate upon the grantee’s termination of employment (or cessation of Service Relationship) with the Company and its Affiliates for any reason.

SECTION 12. TRANSFERABILITY OF AWARDS

(a) Transferability. Except as provided in Section 12(b) below or otherwise determined by the Administrator, during a grantee’s lifetime, his or her Awards shall be exercisable only by the grantee, or by the grantee’s legal representative or guardian in the event of the grantee’s incapacity. No Awards shall be sold, assigned, transferred or otherwise encumbered or disposed of by a grantee other than by will or by the laws of descent and distribution or pursuant to a domestic relations order. No Awards shall be subject, in whole or in part, to attachment, execution, or levy of any kind, and any purported transfer in violation hereof shall be null and void.

(b) Administrator Action. Notwithstanding Section 12(a), the Administrator, in its discretion, may provide either in the Award Agreement regarding a given Award or by subsequent written approval that the grantee (who is an employee or Non-Employee Director) may transfer his or her Non-Qualified Stock Options to his or her immediate family members, to trusts for the benefit of such family members, or to partnerships in which such family members are the only partners, provided that the transferee agrees in writing with the Company to be bound by all of the terms and conditions of this Plan and the applicable Award Agreement. In no event may an Award be transferred by a grantee for value.

13

(c) Family Member. For purposes of Section 12(b), “family member” shall mean a grantee’s child, stepchild, grandchild, parent, stepparent, grandparent, spouse, former spouse, sibling, niece, nephew, mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law, or sister-in-law, including adoptive relationships, any person sharing the grantee’s household (other than a tenant of the grantee), a trust in which these persons (or the grantee) have more than 50 percent of the beneficial interest, a foundation in which these persons (or the grantee) control the management of assets, and any other entity in which these persons (or the grantee) own more than 50 percent of the voting interests.

(d) Designation of Beneficiary. To the extent permitted by the Company and valid under applicable law, each grantee to whom an Award has been made under the Plan may designate a beneficiary or beneficiaries to exercise any Award or receive any payment under any Award payable on or after the grantee’s death. Any such designation shall be on a form provided for that purpose by the Administrator and shall not be effective until received by the Administrator. If no beneficiary has been designated by a deceased grantee, or if the designated beneficiaries have predeceased the grantee, the beneficiary shall be the grantee’s estate or legal heirs.

SECTION 13. TAX WITHHOLDING

(a) Payment by Grantee. Each grantee shall, no later than the date as of which the value of an Award or of any Stock or other amounts received thereunder first becomes includable in the gross income of the grantee for tax purposes, pay to the Company or any applicable Affiliate, or make arrangements satisfactory to the Administrator regarding payment of, any U.S. and non-U.S. federal, state, or local taxes of any kind required by law to be withheld by the Company or any applicable Affiliate with respect to such income. The Company and its Affiliates shall, to the extent permitted by law, have the right to deduct any such taxes from any payment of any kind otherwise due to the grantee or to satisfy any applicable withholding obligations by any other method of withholding that the Company and its Affiliates deem appropriate. The Company’s obligation to deliver evidence of book entry (or stock certificates) to any grantee is subject to and conditioned on tax withholding obligations being satisfied by the grantee.

(b) Payment in Stock. The Administrator may cause any tax withholding obligation of the Company or any applicable Affiliate to be satisfied, in whole or in part, by the Company withholding from shares of Stock to be issued pursuant to any Award a number of shares with an aggregate Fair Market Value (as of the date the withholding is effected) that would satisfy the withholding amount due; provided, however, that the amount withheld does not exceed the maximum statutory rate or such lesser amount as is necessary to avoid liability accounting treatment. For purposes of share withholding, the Fair Market Value of withheld shares shall be determined in the same manner as the value of Stock includible in income of the grantees. The Administrator may also require any tax withholding obligation of the Company or any applicable Affiliate to be satisfied, in whole or in part, by an arrangement whereby a certain number of shares of Stock issued pursuant to any Award are immediately sold and proceeds from such sale are remitted to the Company or any applicable Affiliate in an amount that would satisfy the withholding amount due.

14

SECTION 14. SECTION 409A AWARDS

Awards are intended to be exempt from Section 409A to the greatest extent possible and to otherwise comply with Section 409A. The Plan and all Awards shall be interpreted in accordance with such intent. To the extent that any Award is determined to constitute “nonqualified deferred compensation” within the meaning of Section 409A (a “409A Award”), the Award shall be subject to such additional rules and requirements as specified by the Administrator from time to time in order to comply with Section 409A. In this regard, if any amount under a 409A Award is payable upon a “separation from service” (within the meaning of Section 409A) to a grantee who is then considered a “specified employee” (within the meaning of Section 409A), then no such payment shall be made prior to the date that is the earlier of (i) six months and one day after the grantee’s separation from service, or (ii) the grantee’s death, but only to the extent such delay is necessary to prevent such payment from being subject to interest, penalties and/or additional tax imposed pursuant to Section 409A. Further, the settlement of any 409A Award may not be accelerated except to the extent permitted by Section 409A. The Company makes no representation that any or all of the payments or benefits described in the Plan will be exempt from or comply with Section 409A of the Code and makes no undertaking to preclude Section 409A of the Code from applying to any such payment. The grantee shall be solely responsible for the payment of any taxes and penalties incurred under Section 409A.

SECTION 15. TERMINATION OF SERVICE RELATIONSHIP, TRANSFER, LEAVE OF ABSENCE, ETC.

(a) Termination of Service Relationship. If the grantee’s Service Relationship is with an Affiliate and such Affiliate ceases to be an Affiliate, the grantee shall be deemed to have terminated his or her Service Relationship for purposes of the Plan.

(b) For purposes of the Plan, the following events shall not be deemed a termination of a Service Relationship:

(i) a transfer to the Service Relationship of the Company from an Affiliate or from the Company to an Affiliate, or from one Affiliate to another; or

(ii) an approved leave of absence, if the employee’s right to re-employment is guaranteed either by a statute or by contract or under the policy pursuant to which the leave of absence was granted or if the Administrator otherwise so provides in writing.

SECTION 16. AMENDMENTS AND TERMINATION

The Board may, at any time, amend or discontinue the Plan and the Administrator may, at any time, amend or cancel any outstanding Award for the purpose of satisfying changes in law or for any other lawful purpose, but no such action shall materially and adversely affect rights under any outstanding Award without the holder’s consent. Except as provided in Section 3(c) or 3(d), without prior stockholder approval, in no event may the Administrator exercise its discretion to reduce the exercise price of outstanding Stock Options or Stock Appreciation Rights or effect

15

repricing through cancellation and re-grants or cancellation of Stock Options or Stock Appreciation Rights in exchange for cash or other Awards. To the extent required under the rules of any securities exchange or market system on which the Stock is listed, or to the extent determined by the Administrator to be required by the Code to ensure that Incentive Stock Options granted under the Plan are qualified under Section 422 of the Code, Plan amendments shall be subject to approval by Company stockholders. Nothing in this Section 16 shall limit the Administrator’s authority to take any action permitted pursuant to Section 3(c) or 3(d).

SECTION 17. STATUS OF PLAN

With respect to the portion of any Award that has not been exercised and any payments in cash, Stock or other consideration not received by a grantee, a grantee shall have no rights greater than those of a general creditor of the Company unless the Administrator shall otherwise expressly determine in connection with any Award or Awards. In its sole discretion, the Administrator may authorize the creation of trusts or other arrangements to meet the Company’s obligations to deliver Stock or make payments with respect to Awards hereunder, provided that the existence of such trusts or other arrangements is consistent with the foregoing sentence.

SECTION 18. GENERAL PROVISIONS

(a) No Distribution. The Administrator may require each person acquiring Stock pursuant to an Award to represent to and agree with the Company in writing that such person is acquiring the shares without a view to distribution thereof.

(b) Issuance of Stock. To the extent certificated, stock certificates to grantees under this Plan shall be deemed delivered for all purposes when the Company or a stock transfer agent of the Company shall have mailed such certificates in the United States mail, addressed to the grantee, at the grantee’s last known address on file with the Company. Uncertificated Stock shall be deemed delivered for all purposes when the Company or a Stock transfer agent of the Company shall have given to the grantee by electronic mail (with proof of receipt) or by United States mail, addressed to the grantee, at the grantee’s last known address on file with the Company, notice of issuance and recorded the issuance in its records (which may include electronic “book entry” records). Notwithstanding anything herein to the contrary, the Company shall not be required to issue or deliver any evidence of book entry or certificates evidencing shares of Stock pursuant to the exercise or settlement of any Award, unless and until the Administrator has determined, with advice of counsel (to the extent the Administrator deems such advice necessary or advisable), that the issuance and delivery is in compliance with all applicable laws, regulations of governmental authorities and, if applicable, the requirements of any exchange on which the shares of Stock are listed, quoted or traded. Any Stock issued pursuant to the Plan shall be subject to any stop-transfer orders and other restrictions as the Administrator deems necessary or advisable to comply with federal, state or foreign jurisdiction, securities or other laws, rules and quotation system on which the Stock is listed, quoted or traded. The Administrator may place legends on any Stock certificate or notations on any book entry to reference restrictions applicable to the Stock. In addition to the terms and conditions provided herein, the Administrator may require that an individual make such reasonable covenants, agreements, and representations as the Administrator, in its discretion, deems necessary or advisable in order to comply with any such laws, regulations, or requirements. The Administrator shall have the right to require any individual to comply with any timing or other restrictions with respect to the settlement or exercise of any Award, including a window-period limitation, as may be imposed in the discretion of the Administrator.

16

(c) Stockholder Rights. Until Stock is deemed delivered in accordance with Section 18(b), no right to vote or receive dividends or any other rights of a stockholder will exist with respect to shares of Stock to be issued in connection with an Award, notwithstanding the exercise of a Stock Option or any other action by the grantee with respect to an Award.

(d) Other Incentive Arrangements; No Rights to Continued Service Relationship. Nothing contained in this Plan shall prevent the Board from adopting other or additional incentive arrangements, including trusts, and such arrangements may be either generally applicable or applicable only in specific cases. The adoption of this Plan and the grant of Awards do not confer upon any grantee any right to continued employment or other Service Relationship with the Company or any Affiliate.

(e) Trading Policy Restrictions. Option exercises and other Awards under the Plan shall be subject to the Company’s insider trading policies and procedures, as in effect from time to time.

(f) Clawback Policy. Awards under the Plan shall be subject to the Company’s clawback policy, as in effect from time to time. In addition, the Administrator may impose such other clawback, recovery, or recoupment provisions in an Award Agreement as the Administrator determines necessary or appropriate, including, but not limited to, a reacquisition right in respect of previously acquired shares of Stock or other cash or property upon the occurrence of a termination for “cause” under any agreement with the Company or an Affiliate thereof. No recovery of compensation under such a clawback policy will be an event giving rise to a right to resign for “good reason” or “constructive termination” (or similar term) under any agreement with the Company or an Affiliate thereof.

(g) Fractional Shares. No fractional Shares shall be issued or delivered pursuant to the Plan or any Award, and the Administrator shall determine whether cash, other securities or other property shall be paid or transferred in lieu of any fractional Shares, or whether such fractional Shares or any rights thereto shall be canceled, terminated or otherwise eliminated.

SECTION 19. EFFECTIVE DATE OF PLAN

This Plan shall become effective upon the Closing Date subject to stockholder approval in accordance with applicable state law, the Company’s bylaws and articles of incorporation, and applicable stock exchange rules. No grants of Awards may be made hereunder after the tenth anniversary of the Effective Date and no grants of Incentive Stock Options may be made hereunder after the tenth anniversary of the date the Plan is approved by the Board.

SECTION 20. GOVERNING LAW

This Plan and all Awards and actions taken thereunder shall be governed by, and construed in accordance with the General Corporation Law of the State of Delaware as to matters within the scope thereof, and as to all other matters shall be governed by and construed in accordance with the internal laws of the State of Delaware applied without regard to conflict of law principles.

17

INCENTIVE STOCK OPTION AGREEMENT

UNDER THE KORRO BIO, INC.

2023 STOCK OPTION AND INCENTIVE PLAN

Pursuant to the Korro Bio, Inc. 2023 Stock Option and Incentive Plan as amended through the date hereof (the “Plan”), Korro Bio, Inc. (the “Company”) hereby grants to the Optionee named above an option (the “Stock Option”) to purchase on or prior to the Expiration Date specified above all or part of the number of shares of Common Stock, par value $0.001 per share (the “Stock”), of the Company specified above at the Option Exercise Price per Share specified above subject to the terms and conditions set forth herein and in the Plan.

1. Exercisability Schedule. No portion of this Stock Option may be exercised until such portion shall have become exercisable. Except as set forth below, and subject to the discretion of the Administrator (as defined in Section 2 of the Plan) to accelerate the exercisability schedule hereunder, this Stock Option shall be exercisable with respect to the following number of Option Shares on the dates indicated below so long as the Optionee continues to have a Service Relationship with the Company or a Subsidiary on such dates:

Once exercisable, this Stock Option shall continue to be exercisable at any time or times prior to the close of business on the Expiration Date, subject to the provisions hereof and of the Plan.

2. Manner of Exercise.

(a) The Optionee may exercise this Stock Option only in the following manner: from time to time on or prior to the Expiration Date of this Stock Option, the Optionee may give written notice to the Administrator of his or her election to purchase some or all of the Option Shares purchasable at the time of such notice. This notice shall specify the number of Option Shares to be purchased.

Payment of the purchase price for the Option Shares may be made by one or more of the following methods: (i) in cash, by certified or bank check or other instrument acceptable to the Administrator; (ii) through the delivery (or attestation to the ownership) of shares of Stock that have been purchased by the Optionee on the open market or that are beneficially owned by the Optionee and are not then subject to any restrictions under any Company plan and that otherwise satisfy any holding periods as may be required by the Administrator; or (iii) by the Optionee delivering to the Company a properly executed exercise notice together with irrevocable instructions to a broker to promptly deliver to the Company cash or a check payable and acceptable to the Company to pay the option purchase price, provided that in the event the Optionee chooses to pay the option purchase price as so provided, the Optionee and the broker shall comply with such procedures and enter into such agreements of indemnity and other agreements as the Administrator shall prescribe as a condition of such payment procedure; or (iv) a combination of (i), (ii) and (iii) above. Payment instruments will be received subject to collection.

The transfer to the Optionee on the records of the Company or of the transfer agent of the Option Shares will be contingent upon (i) the Company’s receipt from the Optionee of the full purchase price for the Option Shares, as set forth above, (ii) the fulfillment of any other requirements contained herein or in the Plan or in any other agreement or provision of laws, and (iii) the receipt by the Company of any agreement, statement or other evidence that the Company may require to satisfy itself that the issuance of Stock to be purchased pursuant to the exercise of Stock Options under the Plan and any subsequent resale of the shares of Stock will be in compliance with applicable laws and regulations. In the event the Optionee chooses to pay the purchase price by previously-owned shares of Stock through the attestation method, the number of shares of Stock transferred to the Optionee upon the exercise of the Stock Option shall be net of the Shares attested to.

(b) The shares of Stock purchased upon exercise of this Stock Option shall be transferred to the Optionee on the records of the Company or of the transfer agent upon compliance to the satisfaction of the Administrator with all requirements under applicable laws or regulations in connection with such transfer and with the requirements hereof and of the Plan. The determination of the Administrator as to such compliance shall be final and binding on the Optionee. The Optionee shall not be deemed to be the holder of, or to have any of the rights of a holder with respect to, any shares of Stock subject to this Stock Option unless and until this Stock Option shall have been exercised pursuant to the terms hereof, the Company or the transfer agent shall have transferred the shares to the Optionee, and the Optionee’s name shall have been entered as the stockholder of record on the books of the Company. Thereupon, the Optionee shall have full voting, dividend and other ownership rights with respect to such shares of Stock.

2

(c) Notwithstanding any other provision hereof or of the Plan, no portion of this Stock Option shall be exercisable after the Expiration Date hereof.

3. Termination of Service Relationship. If the Optionee’s Service Relationship with the Company or a Subsidiary (as defined in the Plan) is terminated, the period within which to exercise the Stock Option may be subject to earlier termination as set forth below.

(a) Termination Due to Death. If the Optionee’s Service Relationship with the Company or a Subsidiary terminates by reason of the Optionee’s death, any portion of this Stock Option outstanding on such date, to the extent exercisable on the date of death, may thereafter be exercised by the Optionee’s legal representative or legatee for a period of 12 months from the date of death or until the Expiration Date, if earlier. Any portion of this Stock Option that is not exercisable on the date of death shall terminate immediately and be of no further force or effect.

(b) Termination Due to Disability. If the Optionee’s Service Relationship with the Company or a Subsidiary terminates by reason of the Optionee’s disability (as determined by the Administrator), any portion of this Stock Option outstanding on such date, to the extent exercisable on the date of such termination, may thereafter be exercised by the Optionee for a period of 12 months from the date the Optionee’s Service Relationship is terminated by reason of the Optionee’s disability or until the Expiration Date, if earlier. Any portion of this Stock Option that is not exercisable on the date of the termination of the Optionee’s Service Relationship by reason of the Optionee’s disability shall terminate immediately and be of no further force or effect.

(c) Termination for Cause. If the Optionee’s Service Relationship with the Company or a Subsidiary terminates for Cause, any portion of this Stock Option outstanding on such date shall terminate immediately and be of no further force and effect. For purposes hereof, “Cause” shall mean, unless otherwise provided in an employment or service agreement between the Company and the Optionee, a determination by the Administrator that the Optionee shall be dismissed as a result of (i) any material breach by the Optionee of any agreement between the Optionee and the Company; (ii) the conviction of, indictment for or plea of nolo contendere by the Optionee to a felony or a crime involving moral turpitude; or (iii) any material misconduct or willful and deliberate non-performance (other than by reason of disability) by the Optionee of the Optionee’s duties to the Company.

(d) Other Termination. If the Optionee’s Service Relationship with the Company or a Subsidiary terminates for any reason other than the Optionee’s death, the Optionee’s disability, or Cause, and unless otherwise determined by the Administrator, any portion of this Stock Option outstanding on such date may be exercised, to the extent exercisable on the date of termination, for a period of three months from the date of termination or until the Expiration Date, if earlier. Any portion of this Stock Option that is not exercisable on the date of termination shall terminate immediately and be of no further force or effect.

The Administrator’s determination of the reason for termination of the Optionee’s Service Relationship with the Company or a Subsidiary shall be conclusive and binding on the Optionee and his or her representatives or legatees.

3

4. Incorporation of Plan. Notwithstanding anything herein to the contrary, this Stock Option shall be subject to and governed by all the terms and conditions of the Plan, including the powers of the Administrator set forth in Section 2(b) of the Plan. Capitalized terms in this Agreement shall have the meaning specified in the Plan, unless a different meaning is specified herein.

5. Transferability. This Agreement is personal to the Optionee, is non-assignable and is not transferable in any manner, by operation of law or otherwise, other than by will or the laws of descent and distribution. This Stock Option is exercisable, during the Optionee’s lifetime, only by the Optionee, and thereafter, only by the Optionee’s legal representative or legatee.

6. Status of the Stock Option. This Stock Option is intended to qualify as an “incentive stock option” under Section 422 of the Internal Revenue Code of 1986, as amended (the “Code”), but the Company does not represent or warrant that this Stock Option qualifies as such. The Optionee should consult with his or her own tax advisors regarding the tax effects of this Stock Option and the requirements necessary to obtain favorable income tax treatment under Section 422 of the Code, including, but not limited to, holding period requirements and that this Stock Option must be exercised within three months after termination of employment as an employee (or 12 months in the case of death or disability) to qualify as an “incentive stock option.” To the extent any portion of this Stock Option does not so qualify as an “incentive stock option,” such portion shall be deemed to be a non-qualified stock option. If the Optionee intends to dispose or does dispose (whether by sale, gift, transfer or otherwise) of any Option Shares within the one-year period beginning on the date after the transfer of such shares to him or her, or within the two-year period beginning on the day after the grant of this Stock Option, he or she will so notify the Company within 30 days after such disposition.

7. Tax Withholding. The Optionee shall, not later than the date as of which the exercise of this Stock Option becomes a taxable event for Federal income tax purposes, pay to the Company or make arrangements satisfactory to the Administrator for payment of any Federal, state, and local taxes required by law to be withheld on account of such taxable event. The Company shall have the authority to cause the required tax withholding obligation to be satisfied, in whole or in part, by (i) withholding from shares of Stock to be issued to the Optionee a number of shares of Stock with an aggregate Fair Market Value that would satisfy the withholding amount due; or (ii) causing its transfer agent to sell from the number of shares of Stock to be issued to the Optionee, the number of shares of Stock necessary to satisfy the Federal, state and local taxes required by law to be withheld from the Optionee on account of such transfer.

8. No Obligation to Continue Service Relationship. Neither the Company nor any Subsidiary is obligated by or as a result of the Plan or this Agreement to continue the Optionee in a Service Relationship with the Company or a Subsidiary and neither the Plan nor this Agreement shall interfere in any way with the right of the Company or any Subsidiary to terminate the Optionee’s Service Relationship with the Company or a Subsidiary at any time.

4

9. Integration. This Agreement constitutes the entire agreement between the parties with respect to this Stock Option and supersedes all prior agreements and discussions between the parties concerning such subject matter.

10. Data Privacy Consent. In order to administer the Plan and this Agreement and to implement or structure future equity grants, the Company, its subsidiaries and affiliates and certain agents thereof (together, the “Relevant Companies”) may process any and all personal or professional data, including but not limited to Social Security or other identification number, home address and telephone number, date of birth and other information that is necessary or desirable for the administration of the Plan and/or this Agreement (the “Relevant Information”). By entering into this Agreement, the Optionee (i) authorizes the Company to collect, process, register and transfer to the Relevant Companies all Relevant Information; (ii) waives any privacy rights the Optionee may have with respect to the Relevant Information; (iii) authorizes the Relevant Companies to store and transmit such information in electronic form; and (iv) authorizes the transfer of the Relevant Information to any jurisdiction in which the Relevant Companies consider appropriate. The Optionee shall have access to, and the right to change, the Relevant Information. Relevant Information will only be used in accordance with applicable law.

11. Notices. Notices hereunder shall be mailed or delivered to the Company at its principal place of business and shall be mailed or delivered to the Optionee at the address on file with the Company or, in either case, at such other address as one party may subsequently furnish to the other party in writing.

12. [Clawback Acknowledgement. The Optionee acknowledges that the Optionee may become subject to the Korro Bio, Inc. Compensation Recovery Policy adopted pursuant to Rule 10D-1 promulgated under the Exchange Act and Nasdaq Rule 5608, or any successor rule (the “Clawback Policy”). The Optionee understands that if the Optionee is or becomes subject to the Clawback Policy, the Company and/or the Board shall be entitled to recover all Erroneously Awarded Compensation (as defined in the Clawback Policy) from the Optionee pursuant to such means as the Company and/or the Board may elect. The Optionee agrees that the Optionee shall take all required action to enable such recovery. The Optionee understands that such recovery may be sought and occur after the Executive’s employment or service with the Company terminates. The Optionee further agrees that the Optionee is not entitled to indemnification for any Erroneously Awarded Compensation or for any claim or losses arising out of or in any way related to Erroneously Awarded Compensation recovered pursuant to the Clawback Policy and, to the extent any agreement or organizational document purports to provide otherwise, the Optionee hereby irrevocably agrees to forego such indemnification. The Optionee acknowledges and agrees that the Optionee has received and has had an opportunity to review the Clawback Policy. Any action by the Company to recover Erroneously Awarded Compensation under the Clawback Policy from the Optionee shall not, whether alone or in combination with any other action, event or condition, be deemed (i) an event giving rise to a right to resign for a Good Reason Condition (as defined in the Optionee’s employment agreement with the Company) or serve as a basis for a claim of constructive termination under any benefits or compensation arrangement applicable to the Optionee, or (ii) to constitute a breach of a contract or other

5

arrangement to which the Optionee is a party. This Section 12 is a material term of this Agreement.] ¹

The foregoing Agreement is hereby accepted and the terms and conditions thereof hereby agreed to by the undersigned. Electronic acceptance of this Agreement pursuant to the Company’s instructions to the Optionee (including through an online acceptance process) is acceptable.

6

NON-QUALIFIED STOCK OPTION AGREEMENT

FOR NON-EMPLOYEE DIRECTORS

UNDER THE KORRO BIO, INC.

2023 STOCK OPTION AND INCENTIVE PLAN

Pursuant to the Korro Bio, Inc. 2023 Stock Option and Incentive Plan as amended through the date hereof (the “Plan”), Korro Bio, Inc. (the “Company”) hereby grants to the Optionee named above, who is a Non-Employee Director of the Company but is not an employee of the Company, an option (the “Stock Option”) to purchase on or prior to the Expiration Date specified above all or part of the number of shares of Common Stock, par value $0.001 per share (the “Stock”), of the Company specified above at the Option Exercise Price per Share specified above subject to the terms and conditions set forth herein and in the Plan. This Stock Option is not intended to be an “incentive stock option” under Section 422 of the Internal Revenue Code of 1986, as amended.

1. Exercisability Schedule. No portion of this Stock Option may be exercised until such portion shall have become exercisable. Except as set forth below, and subject to the discretion of the Administrator (as defined in Section 2 of the Plan) to accelerate the exercisability schedule hereunder, this Stock Option shall be exercisable with respect to the following number of Option Shares on the dates indicated below so long as the Optionee continues to serve as a member of the Company’s Board of Directors on such dates:

Notwithstanding the foregoing, in the event of a Sale Event, 100% of the then- outstanding and unvested Option Shares shall immediately be deemed vested and exercisable on the date of such Sale Event; provided, that the Optionee continues to serve as a member of the Company’s Board of Directors until the date of such Sale Event. Once exercisable, this Stock Option shall continue to be exercisable at any time or times prior to the close of business on the Expiration Date, subject to the provisions hereof and of the Plan.

2. Manner of Exercise.

(a) The Optionee may exercise this Stock Option only in the following manner: from time to time on or prior to the Expiration Date of this Stock Option, the Optionee may give written notice to the Administrator of his or her election to purchase some or all of the Option Shares purchasable at the time of such notice. This notice shall specify the number of Option Shares to be purchased.

Payment of the purchase price for the Option Shares may be made by one or more of the following methods: (i) in cash, by certified or bank check or other instrument acceptable to the Administrator; (ii) through the delivery (or attestation to the ownership) of shares of Stock that have been purchased by the Optionee on the open market or that are beneficially owned by the Optionee and are not then subject to any restrictions under any Company plan and that otherwise satisfy any holding periods as may be required by the Administrator; (iii) by the Optionee delivering to the Company a properly executed exercise notice together with irrevocable instructions to a broker to promptly deliver to the Company cash or a check payable and acceptable to the Company to pay the option purchase price, provided that in the event the Optionee chooses to pay the option purchase price as so provided, the Optionee and the broker shall comply with such procedures and enter into such agreements of indemnity and other agreements as the Administrator shall prescribe as a condition of such payment procedure; (iv) by a “net exercise” arrangement pursuant to which the Company will reduce the number of shares of Stock issuable upon exercise by the largest whole number of shares with a Fair Market Value that does not exceed the aggregate exercise price; or (v) a combination of (i), (ii), (iii) and (iv) above. Payment instruments will be received subject to collection.

The transfer to the Optionee on the records of the Company or of the transfer agent of the Option Shares will be contingent upon (i) the Company’s receipt from the Optionee of the full purchase price for the Option Shares, as set forth above, (ii) the fulfillment of any other requirements contained herein or in the Plan or in any other agreement or provision of laws, and (iii) the receipt by the Company of any agreement, statement or other evidence that the Company may require to satisfy itself that the issuance of Stock to be purchased pursuant to the exercise of Stock Options under the Plan and any subsequent resale of the shares of Stock will be in compliance with applicable laws and regulations. In the event the Optionee chooses to pay the purchase price by previously-owned shares of Stock through the attestation method, the number of shares of Stock transferred to the Optionee upon the exercise of the Stock Option shall be net of the Shares attested to.

2