BIVV Bioverativ Inc. (delisted)

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Employee Benefits

        Pursuant to the Merger Agreement, from and after the Effective Time, Sanofi is required to honor, and will cause the Surviving Corporation to honor, all employee plans and all employment, severance and termination plans and agreements, in each case in accordance with their terms as in effect immediately before the Effective Time and will assume any employee plans that require or contemplate assumption by their terms by an acquirer or successor. Sanofi will provide, or will cause to be provided, to each Bioverativ employee immediately before the Effective Time (including any of our executive officers) who is employed by the Surviving Corporation or any Subsidiary of the Surviving Corporation immediately following the Effective Time (which we refer to as " Continuing Employees ") for a period of one year following the Effective Time, (i) base salary and base wages, short-term cash incentive compensation opportunities and severance payments and severance benefits (in the case of severance plans and benefits, in each case, in accordance with the severance plans and guidelines described in the Company's disclosure schedules to the Merger Agreement), in each case in an amount no less favorable than that in effect immediately prior to the execution of the Merger Agreement and (ii) benefits (other than equity compensation) that are substantially comparable in the aggregate to the other such benefits provided to such Continuing Employees immediately prior to the execution of the Merger Agreement.

        From and after the closing of the Merger, with respect to Continuing Employees, Sanofi will cause the service of each such Continuing Employee with Bioverativ and its subsidiaries prior to the closing date of the Merger to be recognized for purposes of eligibility to participate, levels of benefits (but not for benefit accruals or participation eligibility under any defined benefit pension plan or plan providing post-retirement medical or other similar benefits) and vesting under each compensation, vacation, fringe or other welfare benefit plan, program or arrangement of the Surviving Corporation, but not including any sabbatical or equity compensation plans, programs, agreements or arrangements (which we refer to collectively as the " Sanofi Benefit Plans ") in which any Continuing Employee is or becomes eligible to participate, but solely to the extent that service was credited to such employee for such purposes under a comparable Bioverativ employee plan immediately prior to the closing date and to the extent that such credit would not result in a duplication of benefits.

        From and after the closing date of the Merger, with respect to each Sanofi Benefit Plan that is an "employee welfare benefit plan," in which any Continuing Employee is or becomes eligible to participate, Sanofi will use commercially reasonable efforts to cause each such Sanofi Benefit Plan to waive all limitations as to pre-existing conditions, waiting periods, required physical examinations and exclusions with respect to participation and coverage requirements applicable under such Sanofi Benefit Plan for such Continuing Employees and their eligible dependents to the same extent that such pre-existing conditions, waiting periods, required physical examinations and exclusions would not have applied or would have been waived under the corresponding Bioverativ employee plan in which such Continuing Employee was a participant immediately prior to his commencement of participation in such Sanofi Benefit Plan but only to the extent permitted under the terms and conditions of Sanofi's applicable insurance contracts in effect as of the closing date of the Merger.

        With respect to any accrued but unused personal, sick or vacation time to which any Continuing Employee is entitled pursuant to the personal, sick or vacation policies applicable to such Continuing Employee immediately prior to the Effective Time, Sanofi will, or will cause the Surviving Corporation to and instruct its affiliates to, as applicable (and without duplication of benefits), assume the liability for such accrued but unused personal, sick or vacation time and allow such Continuing Employee to use such accrued personal, sick or vacation time in accordance with the practice and policies of Bioverativ, as they may be amended from time to time.

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Section 16 Matters

        Prior to the consummation of the Offer, the Company and our Board of Directors are required to take all actions to the extent necessary or as may be reasonably requested by any party to the Merger Agreement to cause the transactions with respect to outstanding Company Equity Awards and any and all other dispositions or cancellations of Company equity securities (including any deemed dispositions or cancellations and any derivative securities with respect to any equity securities of the Company), in each case, by each individual who is a Company director or officer, and who would otherwise be subject to Rule 16b-3 under the Exchange Act, to be exempt under Exchange Act Rule 16b-3.

Rule 14d-10(d) Matters

        In connection with approving the Company's entry into the Merger Agreement and the Transactions, the Compensation Committee of our Board of Directors approved each agreement, arrangement or understanding that has been, or will be, entered into by the Company with any of its officers, directors or employees pursuant to which compensation, severance or other benefits is paid to such officer, director or employee as an "employment compensation, severance or other employee benefit arrangement" within the meaning of Rule 14d-10(d)(1) under the Exchange Act and otherwise took all necessary and appropriate actions to satisfy the requirements of the non-exclusive safe harbor set forth in Rule 14d-10(d) under the Exchange Act.

Potential for Future Arrangements

        To our knowledge, except for certain agreements described in this Schedule 14D-9, or in the documents incorporated by reference herein between the Company and its executive officers and directors, no employment, equity contribution or other agreement, arrangement or understanding between any executive officer or director of the Company, on the one hand, and Sanofi, Purchaser, any of their respective affiliates or the Company, on the other hand, existed as of the date of this Schedule 14D-9, and neither the Offer nor the Merger is conditioned upon any executive officer or director of the Company entering into any such agreement, arrangement or understanding.

        Although such arrangements have not, to our knowledge, been discussed as of the date of this Schedule 14D-9, it is possible that additional members of our current management team will enter into new employment or consulting arrangements with the Surviving Corporation. Such arrangements may include the right to purchase or participate in the equity of Purchaser or its affiliates. Any such arrangements with our existing management team are currently expected to be entered into after the completion of the Offer and will not become effective until after the Merger is completed, if at all. There can be no assurance that the applicable parties will reach an agreement on any terms, or at all.

Director Compensation

        Annual compensation for our non-employee directors is as follows:

•

An annual cash retainer of $60,000, which may, at the election of the director, be paid in Shares in lieu of such cash retainer; and



•

For each term of service after the initial term, an annual equity retainer with a grant date value of $300,000, divided equally between Options and full value awards such as RSUs. The annual equity retainer will generally vest on the first anniversary of the date of grant (subject to continued service) and will be granted pursuant to the Directors Plan.

        In addition to the foregoing remuneration (i) our non-executive chair of the Board of Directors is entitled to receive an additional $100,000 annual retainer, $50,000 of which is payable in cash, and, in 2017, the remaining $50,000 was an initial supplemental grant of Options vesting ratably on each of the first three anniversaries of the date of grant and, for years subsequent to 2017, the remaining $50,000

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will be a supplemental grant of RSUs generally vesting on the first anniversary of the date of grant (subject to continued service); (ii) the chair of each of the Audit Committee, Compensation Committee and the Corporate Governance Committee is entitled to receive an additional annual cash retainer of $25,000, $20,000 and $15,000, respectively; and (iii) directors serving on each of the Audit Committee, Compensation Committee and the Corporate Governance Committee, other than the chairs of such committees, receive an additional annual cash retainer of $10,000, $8,000 and $6,000, respectively.

        Each director received an initial election grant of Options with a grant date value of $450,000. The initial election grant will generally vest ratably on each of the first three anniversaries of the date of grant (subject to continued service) and be granted pursuant to the Directors Plan.

        On January 31, 2018, the Company granted each of our non-employee directors 5,455 RSUs, and the non-executive chair received an additional 909 RSUs as the 2018 supplemental grant. These FY18 RSUs are the annual equity retainers for the non-employee directors, which were all granted as RSUs instead of Options. The terms of these awards are otherwise substantially consistent with the terms described in the paragraphs above, provided that such equity awards are also subject to accelerated vesting as provided by the Merger Agreement, as described in more detail in "—Arrangements between the Company and its Executive Officers, Directors and Affiliates—Treatment of Company Equity Awards" of this Schedule 14D-9.

Indemnification of Directors and Officers; Insurance

        The Merger Agreement requires that, prior to the closing of the Merger, the Company is required to use its reasonable best efforts to purchase (in consultation with Parent) a " tail " or " runoff " officers' and directors' liability insurance policy (a " Tail Policy ") in respect of acts or omissions occurring prior to the Effective Time covering each such person currently covered by the Company's officers' and directors' liability insurance policy (the " Current Policy "). The Merger Agreement requires that the terms with respect to coverage, deductibles and amounts of the Tail Policy are no less favorable than those of such policy in effect on the date of the Merger Agreement for the six year period following the closing of the Merger and at a price not to exceed 300% of the amount per annum the Company paid in its last full fiscal year prior to the date of the Merger Agreement (the " Current Premium "). If the Company or Parent obtains a prepaid Tail Policy prior to the Effective Time in accordance with the Merger Agreement, the Surviving Corporation is required to, and Parent is required to cause the Surviving Corporation to, maintain such policies in full force and effect for their full term, and continue to honor the obligations thereunder. If the Company fails to purchase such Tail Policy prior to the closing of the Merger, then either (i) Parent may purchase such Tail Policy on behalf of the Company or the Surviving Corporation or (ii) the Surviving Corporation is required to, and Parent is required to cause the Surviving Corporation to, maintain an officers' and directors' liability insurance policy in respect of acts or omissions occurring prior to the Effective Time covering each such person currently covered by the Current Policy on terms with respect to coverage and amount no less favorable than those of such policy in effect as of the date of the Merger Agreement for a period of six years after the Effective Time (provided that neither Parent nor the Surviving Corporation is required to pay annual premiums in excess of 300% of the Current Premium, and if such premiums would at any time exceed 300% of the Current Premium, Parent or the Surviving Corporation are required to maintain insurance policies that, in their good faith judgment, provide the maximum coverage available at an annual premium equal to 300% of the Current Premium).

        In addition, the Merger Agreement requires Parent, from and after the Effective Time, to cause the Surviving Corporation to fulfill and honor in all respects the obligations of the Company and its subsidiaries pursuant to (i) any indemnification agreement in effect between the Company or any of its subsidiaries and any individual who, at the Effective Time is, or at any time prior to such time was, a director or officer of the Company or of a subsidiary (each, an " Indemnified Party ") that was made publicly available on the EDGAR website or made available to Parent prior to the execution of the

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Merger Agreement, and (ii) any indemnification or exculpation provision set forth in the certificate of incorporation or bylaws of the Company, in each case as in effect on the date of the Merger Agreement. In addition, from the Effective Time through the sixth anniversary of the Effective Time, the certificate of incorporation and bylaws of the Surviving Corporation is required to contain provisions no less favorable with respect to indemnification of each Indemnified Party than are set forth in the certificate of incorporation and bylaws of the Company as in effect on the date of the Merger Agreement.

(b)

Arrangements with Purchaser and Parent and their Affiliates .

Merger Agreement

        On January 21, 2018, the Company, Parent and Purchaser entered into the Merger Agreement. The summary of the material provisions of the Merger Agreement contained in Section 11—"The Merger Agreement; Other Agreements" and the description of the conditions of the Offer contained in Section 15—"Conditions of the Offer" of the Offer to Purchase, which is filed as Exhibit (a)(1)(A) of Schedule TO, are incorporated herein by reference. Such summary and description are qualified in their entirety by reference to the Merger Agreement, which is filed as Exhibit (e)(1) hereto and is incorporated herein by reference.

        The Merger Agreement has been filed as an exhibit to the Current Report on Form 8-K filed by the Company with the SEC on January 22, 2018 to provide stockholders with information regarding its terms. The Merger Agreement and the summary of its terms contained in the Current Report on Form 8-K filed by the Company with the SEC on January 22, 2018, are incorporated herein by reference. The assertions embodied in the representations and warranties contained in the Merger Agreement are qualified by information in confidential disclosure schedules delivered by the Company to Parent and Purchaser in connection with the signing of the Merger Agreement. Moreover, certain representations and warranties in the Merger Agreement were made as of a specified date, may be subject to a contractual standard of materiality different from what might be viewed as material to stockholders, or may have been used for the purpose of allocating risk between the parties to the Merger Agreement. Accordingly, the representations and warranties in the Merger Agreement should not be relied on by any persons as characterizations of the actual state of facts and circumstances of the Company at the time they were made and the information in the Merger Agreement should be considered in conjunction with the entirety of the factual disclosure about the Company in the Company's public reports filed with the SEC. Information concerning the subject matter of the representations and warranties may change after the date of the Merger Agreement, which subsequent information may or may not be fully reflected in the Company's public disclosures. The Merger Agreement should not be read alone, but should instead be read in conjunction with the other information regarding the Transactions, the Company, Parent, Purchaser, their respective affiliates and their respective businesses that are contained in, or incorporated by reference into, the Tender Offer Statement on Schedule TO and related exhibits, including the Offer to Purchase, and this solicitation/recommendation statement on Schedule 14D-9, as well as in the Company's other public filings.

Confidentiality Agreement

        On December 5, 2017, the Company and Parent entered into a customary Confidentiality Agreement (which was effective as of December 4, 2017) (the " Confidentiality Agreement ") in connection with a possible transaction involving Bioverativ. Under the terms of the Confidentiality Agreement, Parent and the Company agreed that, subject to certain exceptions, Parent and its representatives would keep the "Confidential Information" (as defined in the Confidentiality Agreement) strictly confidential and would not (except as required by law but only after compliance with the Confidentiality Agreement or with the Company's prior written consent) disclose any Confidential Information in any manner whatsoever, and would not use any Confidential Information

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other than in connection with evaluating, negotiating or implementing a possible transaction with the Company.

        The Confidentiality Agreement includes a standstill provision for the benefit of the Company that expires on December 4, 2018, but which does not restrict Parent from making a confidential proposal to the Chief Executive Officer or the Board of Directors of the Company regarding certain matters set forth in the standstill provision. The standstill provision will be of no further force and effect if (A) the Company enters into a definitive agreement with a person or "group" of persons involving the direct or indirect acquisition of all or a majority of the Company's equity securities or all or substantially all of the Company's assets, other than in connection with an internal restructuring transaction involving only the Company, one or more of its subsidiaries and/or any holding company formed for the purpose of such transaction or (B) a tender or exchange offer is commenced that, if consummated, would result in all or a majority of the Company's equity securities being owned by persons other than the Company or current holders of the Company's equity securities and the Board of Directors of the Company (or a committee thereof) fails to recommend within ten business days form the date of commencement of such offer that its stockholders reject such offer.

        This summary and description of the Confidentiality Agreement is only a summary and is qualified in its entirety by reference to the Confidentiality Agreement, which is filed as Exhibit (e)(2) hereto and incorporated herein by reference.

Exclusivity Agreement

        The Company and Parent entered into an exclusivity agreement on January 6, 2018 (which was dated as of January 5, 2018) (the " Exclusivity Agreement "), whereby, in connection with Parent's consideration of a possible transaction between the Company and Parent and the requirement that Parent expend a substantial amount of time and resources to evaluate such transaction, the Company and Parent agreed that, from January 5, 2018 through 11:59 p.m. EST on January 26, 2018 (or the earlier execution and delivery of a definitive written agreement providing for a transaction between Parent and the Company), the Company and its representatives would not, directly or indirectly, solicit, initiate, pursue, knowingly facilitate, knowingly encourage, engage in or otherwise enter into any discussions, negotiations, agreements or arrangements (including by providing any non-public information) with any person or entity (other than Parent or its representatives) concerning an Alternative Transaction (as defined in the Exclusivity Agreement). The obligations under the Exclusivity Agreement terminated upon the execution of the Merger Agreement.

        This summary and description of the Exclusivity Agreement is only a summary and is qualified in its entirety by reference to the Exclusivity Agreement, which is filed as Exhibit (e)(3) to this Schedule 14D-9 and is incorporated herein by reference.

Letter Agreement

        On January 21, 2018, Biogen, Parent and the Company entered into a letter agreement (the " Letter Agreement ") in connection with the Merger, which, among other things, addresses aspects of that certain Tax Matters Agreement, dated as of January 31, 2017, by and between Biogen and the Company (the " Tax Matters Agreement "), which was previously filed as Exhibit 2.3 to the Company's Current Report on Form 8-K filed with the SEC on February 2, 2017. Under the Tax Matters Agreement at the time of the Spin-Off, we would potentially be required to indemnify Biogen against taxes incurred by Biogen that arise as a result of our taking or failing to take, as the case may be, certain actions that result in the distribution failing to meet the requirements of a tax-free distribution under Section 355 of the Internal Revenue Code of 1986, as amended (including as a result of the Merger).

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        The Tax Matters Agreement required that, prior to entering into certain significant transactions, the Company obtain a tax opinion, reasonably satisfactory to Biogen, addressing whether the transaction would result in taxes being imposed on Biogen. In the Letter Agreement, Biogen acknowledged that, in connection with the execution and delivery of the Merger Agreement, Biogen received a copy of the opinion from the Company's tax advisor, Paul, Weiss, Rifkind, Wharton & Garrison LLP (" Paul, Weiss "), based on, among other items, representation letters delivered by Parent and the Company, and agreed that the opinion satisfied the applicable requirements under the Tax Matters Agreement with respect to such opinion. Under the Letter Agreement, immediately prior to the closing of the Offer, Parent and the Company have agreed to again deliver representation letters to Paul, Weiss substantially in the form of those delivered prior to the execution of the Merger Agreement. The Letter Agreement also provides that the Company will use its reasonable best efforts to cause Paul, Weiss to deliver the tax opinion required by the Letter Agreement immediately prior to the closing of the Offer. Biogen has agreed that the tax opinion delivered immediately prior to the closing of the Offer, if substantially the same in form and substance as the tax opinion delivered in connection with the execution of the Merger Agreement, will satisfy the applicable requirements under the Tax Matters Agreement with respect to the delivery of such opinion in connection with the consummation of the Offer and Merger.

        Under the Letter Agreement, from and after the closing of the Offer, the Company agreed to continue to indemnify, and Parent agreed to guarantee the Company's performance under such indemnity to, Biogen and each of its affiliates and each of their respective officers, directors and employees against certain tax-related losses resulting from the Transactions.

        The Letter Agreement may be terminated (i) by mutual written consent of the Company, Biogen and Parent or (ii) by Parent or the Company upon termination of the Merger Agreement, in each case, subject to the terms of the Letter Agreement.

        This summary and description of the Letter Agreement is only a summary and is qualified in its entirety by reference to the Letter Agreement, which is filed as Exhibit 99.1 to the Company's Schedule 14D-9C filed with the SEC on January 22, 2018 and is incorporated herein by reference.

Item 4.     The Solicitation or Recommendation.

(i)

Recommendation of the Board of Directors

        On January 21, 2018, our Board of Directors unanimously (i) declared that the Merger Agreement, the Merger and the other Transactions, including the Offer, are advisable, fair to, and in the best interests of, the Company and its stockholders, (ii) adopted and approved the Merger Agreement, the entry by Bioverativ into the Merger Agreement, and the consummation of the Transactions, including the Offer and the Merger, on the terms and subject to the conditions set forth therein, (iii) determined to recommend that the Company's stockholders (other than Parent and its subsidiaries) accept the Offer and tender their Shares to Purchaser pursuant to the Offer, (iv) resolved to take all actions necessary so that the restrictions on business combinations and stockholder vote requirements contained in Section 203 of the DGCL and any other applicable law with respect to a "moratorium," "control share acquisition," "business combination," "fair price" or other forms of anti-takeover laws or regulations that may purport to be applicable will not apply with respect to or as a result of the Merger, the Merger Agreement and the Transactions (including the Offer) and (v) agreed and authorized that the Merger be governed by Section 251(h) of the DGCL and consummated as soon as practicable following the consummation of the Offer. Accordingly, and for other reasons described in more detail below, our Board of Directors unanimously recommends that stockholders tender their Shares to Purchaser pursuant to the Offer. See "Item 4. The Solicitation or Recommendation—Reasons for Recommendation" of this Schedule 14D-9.

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(ii)

Background of the Offer and Merger

        The Company became an independent, publicly traded company on February 1, 2017, when the Company separated from Biogen as a result of a pro rata dividend distribution of all the outstanding shares of common stock of the Company to Biogen stockholders, which we refer to as the " Spin-Off ." Following such time, the Company has regularly evaluated different strategies for improving its competitive position and enhancing stockholder value. As part of these evaluations, the Company has, from time to time, considered various strategic alternatives in pursuing its business plan, including acquisitions, joint ventures, collaborations and other potential business opportunities.

        In May 2017, a representative of Lazard Fréres & Co. LLC (" Lazard "), contacting on behalf of Sanofi, contacted Dr. Alexander Denner, Chief Investment Officer of Sarissa Capital and a member of our Board of Directors, and stated that Sanofi would be interested in having a discussion with the Company. Following this contact, on May 12, 2017, Serge Weinberg, the Chairman of Sanofi, contacted Brian Posner, Chairman of our Board of Directors, to request an opportunity to meet to discuss Sanofi's interest in acquiring the Company. Mr. Posner stated that the Company was not for sale. Following this discussion, the Company contacted a representative of Paul, Weiss to provide legal advice in connection therewith.

        On May 15, 2017, Mr. Weinberg and Mr. Posner had a follow-up call, during the course of which a meeting was scheduled for May 19, 2017.

        A meeting was held on May 19, 2017, in Greenwich, CT, with Dr. Olivier Brandicourt, Chief Executive Officer of Sanofi, Mr. Weinberg, Dr. Denner and Mr. Posner in attendance. During the course of this meeting, Mr. Weinberg discussed Sanofi's interest in acquiring the Company. Mr. Weinberg stated that Sanofi was only interested in pursuing a friendly transaction. At the conclusion of this meeting, Mr. Posner stated that the Company was focused on executing its current business plan and growing its operations as a standalone business but that he would convey Mr. Weinberg's interest to our Board of Directors. Following the meeting, Mr. Posner updated each member of our Board of Directors regarding the substance of the May 19, 2017 meeting.

        On May 23, 2017, Mr. Posner called Mr. Weinberg, confirming that the Company was focused on executing its current business objectives and growing its operations as a standalone business and was not for sale. During that call, Mr. Weinberg acknowledged that he understood and, that from Sanofi's perspective, the matter was now closed. Following the May 23, 2017 call, Mr. Posner sent an email to each member of our Board of Directors with an update on the substance of the May 23, 2017 call, and confirming that Mr. Weinberg informed him that the matter was now closed.

        On September 12, 2017, Mr. Posner received a message from Mr. Weinberg requesting a telephonic conversation. On September 13, 2017, Mr. Posner reported the outreach from Sanofi to the directors at a regularly scheduled meeting of our Board of Directors. During the course of this meeting, our Board of Directors discussed the fact that the Company was not for sale and was focused on executing its current business plan and growing its operations as a standalone business. However, our Board of Directors authorized Mr. Posner to schedule a telephonic discussion with Mr. Weinberg and to report back to our Board of Directors.

        Following the September 13, 2017 meeting of our Board of Directors, Mr. Posner and Mr. Weinberg spoke by telephone on September 15, 2017. In the course of this discussion, Mr. Weinberg expressed Sanofi's interest in pursuing an acquisition of the Company and Mr. Posner stated that our Board of Directors remained confident in the future of the Company as a standalone business and was not interested in pursuing such a transaction at that time. Following the phone call with Mr. Weinberg, Mr. Posner provided a further update to our Board of Directors regarding the substance of the conversation.

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        In late October, 2017, Dr. Denner was contacted by a representative of Lazard inquiring as to the Company's interest in engaging in discussions about a potential transaction with Sanofi. The representatives of Lazard conveyed to Dr. Denner the possibility of Sanofi submitting a private proposal letter with respect to a potential acquisition. Dr. Denner indicated that in order for our Board of Directors to consider entering into discussions with Sanofi regarding a potential transaction, Sanofi must offer a "preemptive" price; i.e., a price that is sufficiently high that it would obviate the need for a pre-signing market check. Dr. Denner reported Lazard's outreach to Mr. Posner. This outreach was then conveyed to the members of our Board of Directors.

        On November 3, 2017, Mr. Posner and Mr. Weinberg spoke by telephone. Mr. Weinberg conveyed details of Sanofi's non-binding acquisition proposal, which included a proposed price of $98.50 per Share, payable in cash. During the course of this discussion, Mr. Posner indicated that the Company was not for sale, but that he would present the Sanofi proposal to our Board of Directors.  Following this discussion, Mr. Weinberg delivered an email to Mr. Posner attaching the Sanofi proposal letter (the " November 3 Proposal "). The November 3 Proposal noted that the price represented an 84% premium to the closing price of the Shares of $53.65 on November 2, 2017, and a premium of 73% to the sixty trading day volume weighted average closing price of $56.92.

        On November 7, 2017, our Board of Directors held a special telephonic meeting with certain members of senior management and representatives from Paul, Weiss in attendance. At the meeting, our Board of Directors reviewed the non-binding November 3 Proposal submitted by Sanofi and discussed next steps with respect to its response to Sanofi. During the course of this meeting, our Board of Directors requested that the Company's management team prepare an overview of the Company's long-range plan as a standalone business. A representative of Paul, Weiss then reviewed certain legal matters for our Board of Directors' consideration in connection with its evaluation of the non-binding November 3 Proposal from Sanofi and reviewed the fiduciary obligations of our Board of Directors. In addition, our Board of Directors discussed the potential engagement of J.P. Morgan Securities LLC (" J.P. Morgan ") and Guggenheim Securities, LLC (" Guggenheim Securities ") as outside financial advisors to the Company, based on, among other things, J.P. Morgan's and Guggenheim Securities' respective credentials as sophisticated investment banks with substantial knowledge and experience in the biopharmaceutical industry and mergers and acquisitions generally, as well as each firm's familiarity with the Company.

        Following this meeting, our Board of Directors voted by written consent to approve the engagement of each of J.P. Morgan, Guggenheim Securities and Paul, Weiss by the Company, subject to finalization of the terms of each such engagement and management initiated negotiation of such engagement letters.

        On November 16, 2017, Mr. Weinberg contacted Mr. Posner requesting an update on when Sanofi could expect a response from the Company regarding Sanofi's non-binding November 3 Proposal. Mr. Posner responded that the Company was reviewing the November 3 Proposal with management and the Company's legal and financial advisors and that the Company would respond to Sanofi as soon as it could.

        On November 21, 2017, a meeting of our Board of Directors was convened to discuss the Company's preliminary long-range plan as a standalone business and the Company's response to Sanofi's non-binding November 3 Proposal. Representatives from J.P. Morgan, Guggenheim Securities, and Paul, Weiss were in attendance as well as members of senior management. At the meeting, certain members of senior management presented the Company's long-range plan as a standalone business, which had been developed to reflect management's views on each of the Company's products and product candidates. Our Board of Directors discussed in detail the financial model, and members of management responded to questions from our Board of Directors in relation to management's projections, including the November 20, 2017 announcement of positive results from Roche's phase III

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Haven 3 study evaluating Hemlibra and its potential impact on the competitive marketplace. The members of senior management, representatives of J.P. Morgan and Guggenheim Securities and our Board of Directors also discussed the Company's performance and its portfolio and product pipeline, as well as assumptions used in preparing the management projections.

        During this meeting, representatives of J.P. Morgan and Guggenheim Securities made a joint presentation with respect to Sanofi's non-binding November 3 Proposal and discussed with our Board of Directors certain financial and market information, including a preliminary illustrative valuation analysis regarding the Company. As part of this discussion, our Board of Directors considered a list prepared by J.P. Morgan and Guggenheim Securities at the direction of our Board of Directors of other industry participants that might be interested in potentially acquiring the Company. In addition, during the course of this meeting, representatives of Paul, Weiss reviewed certain legal matters for the consideration of our Board of Directors in connection with its evaluation of the non-binding offer from Sanofi, including certain tax considerations relevant to any strategic transaction involving the Company in light of the restrictions and obligations under the Tax Matters Agreement and the requirement thereunder to deliver to Biogen a copy of an "unqualified tax opinion" reasonably satisfactory to Biogen with respect to any transaction resulting in a change of control of the Company. Our Board of Directors also discussed the benefits to the Company of avoiding a protracted sales process that could potentially distract the management team at a critical time for the Company. Our Board of Directors weighed the potential benefits and risks, including the potential risk of leaks and the impact that a leak could have on the Company as well as the risk that Sanofi might withdraw its offer if a leak were to occur, of reaching out to a broader or narrower group of other industry participants in order to gauge their interest in submitting a proposal to acquire the Company. Our Board of Directors then determined to reconvene thereafter to continue its deliberations regarding the November 3 Proposal.

        On November 25, 2017, a meeting of our Board of Directors was convened by teleconference to discuss the Company's potential response to the November 3 Proposal. Representatives of J.P. Morgan, Guggenheim Securities and Paul, Weiss were in attendance, as were certain members of senior management. During the course of this meeting, our Board of Directors determined, after careful consideration of the factors that our Board of Directors deemed relevant to its determination, including the potential risk of a leak and the impact that a leak could have on the Company as well as the risk that Sanofi might withdraw its offer if a leak were to occur, not to contact a targeted group of industry participants at that time because, among other reasons, of the tax considerations relevant to any strategic transaction involving the Company in light of the restrictions and obligations under the Tax Matters Agreement, including the requirement thereunder to deliver to Biogen a copy of an "unqualified tax opinion" with respect to any transaction resulting in a change of control of the Company, and the benefits to the Company of avoiding a protracted sales process that could potentially distract the management team at a critical time for the Company. Our Board of Directors also authorized the Company to negotiate and enter into a confidentiality agreement with Sanofi that would include customary standstill provisions with a customary "fall away" provision providing that the standstill obligations would terminate in certain circumstances, including upon the Company entering into a binding agreement related to a change of control of the Company, in order to facilitate discussions between the parties. At the conclusion of this meeting, our Board of Directors based on the foregoing directed Mr. Posner to communicate to Sanofi that the offer price of $98.50 per Share did not reflect the full value of the Company, but that the Company was willing to have members of the Company's senior management meet with Sanofi to discuss the Company's long-range plan as a standalone business and other sources of value with a view toward Sanofi submitting a revised proposal if it wished to do so.

        On November 27, 2017, Mr. Posner had a telephonic discussion with Mr. Weinberg, during which Mr. Posner communicated the message that had been authorized by our Board of Directors regarding the insufficiency of the November 3 Proposal and an offer for a management presentation. On the call,

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Mr. Weinberg stated that he would need to confer with others at Sanofi prior to agreeing to a management presentation.

        On November 29, 2017, Mr. Weinberg called Mr. Posner, and accepted the Company's offer to participate in a management presentation, which was subsequently arranged to be held on December 18, 2017.

        On December 1, 2017, Paul, Weiss delivered a draft confidentiality agreement to Weil, Gotshal & Manges LLP (" Weil "), counsel to Sanofi, which contained customary standstill provisions with a customary "fall away" provision providing that the standstill obligations would terminate in certain circumstances, including upon the Company entering into a binding agreement related to a change of control of the Company. Over the next three days, Paul, Weiss and Weil negotiated the terms of such confidentiality agreement. On December 5, 2017, the Company and Sanofi entered into the Confidentiality Agreement (which was effective as of December 4, 2017 and included customary standstill provisions for a period of one year with a customary "fall away" provision providing that the standstill obligations would terminate in certain circumstances) in connection with the sharing of certain confidential information of the Company with Sanofi, a copy of which is filed as Exhibit (e)(2) hereto and incorporated herein by reference. See "Item 3. Past Contacts, Transactions, Negotiations and Agreements—Arrangements with Purchaser and Parent and their Affiliates—Confidentiality Agreement."

        On, December 14, 2017, our Board of Directors convened a meeting with certain members of senior management by teleconference to discuss the upcoming management meeting with Sanofi to be held on December 18, 2017. This meeting was attended by J.P. Morgan, Guggenheim Securities and Paul, Weiss. Certain members of senior management provided our Board of Directors with an overview of the management presentation that would be presented on December 18, 2017. During the course of the meeting, our Board of Directors discussed the agenda for the upcoming meeting as well the management projections contained in the management presentation and the assumptions underlying such projections with members of senior management and representatives of J.P. Morgan and Guggenheim Securities.

        On December 15, 2017, a meeting of the independent directors of our Board of Directors was convened to discuss the Company's upcoming management meeting with Sanofi to be held on December 18, 2017. This meeting was attended by representatives of Paul, Weiss. During the course of this meeting, our Board of Directors discussed the Company's long-range plan as a standalone business, the assumptions underlying the management projections, the benefits of a cash payment to the Company's stockholders as compared to the risk of achieving the goals of the Company's long-range plan and the Company's strategy for engaging in discussions with Sanofi.

        On December 17, 2017, our Board of Directors convened a meeting to discuss the Company's upcoming management presentation to Sanofi. This meeting was attended by representatives of Paul, Weiss. During the course of this meeting, our Board of Directors discussed the Company's long-range plan as a standalone business, the assumptions underlying the management projections and the Company's strategy for engaging in discussions with Sanofi.

        On December 18, 2017, the management presentation meeting was held in-person at the offices of Paul, Weiss in New York City. During this meeting, Richard Brudnick, Lucia Celona, John Cox, Chief Executive Officer of the Company, Dr. Denner, Andrea DiFabio, Chief Legal Officer of the Company, Tim Harris, John Greene, Chief Financial Officer of the Company, Mr. Posner and Dr. Rogerio Vivaldi on behalf of the Company, and representatives of J.P. Morgan and Guggenheim Securities, met with senior representatives of Sanofi and representatives of Lazard and Weil to discuss management's projections and assumptions supporting management's projections, the Company's product pipeline and next generation products, various therapeutic approaches, as well as general trends in the hemophilia marketplace. At the conclusion of the meeting, Mr. Cox, Dr. Denner and Mr. Posner on behalf of the

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Company, and Dr. Brandicourt and Mr. Weinberg on behalf of Sanofi, met in a private session to discuss Sanofi's non-binding November 3 Proposal. During this meeting, the Company's representatives stated that they believed the management presentation highlighted the Company's value above and beyond the value presented in the November 3 Proposal and Sanofi's representatives indicated an intent to consider what the Company had presented during the management presentation and to determine what impact, if any, such presentation would have on Sanofi's views regarding the Company's value.

        On December 18 and 19, 2017, our Board of Directors held its regularly scheduled meeting at the offices of Paul, Weiss in New York City. In addition to addressing the regular business of the Company, our Board of Directors deliberated on the discussions with Sanofi, and portions of the meetings were attended by representatives of J.P. Morgan, Guggenheim Securities and Paul, Weiss.

        On December 20, 2017, representatives from Lazard provided J.P. Morgan and Guggenheim Securities with a list of additional questions from Sanofi, as follow up to the December 18 management presentation.

        On December 21, 2017, Mr. Posner notified our Board of Directors that the Company was responding to follow up questions from Sanofi.

        On December 21, 2017, representatives from J.P. Morgan and Guggenheim Securities had discussions with representatives from Lazard regarding the work plan for responding to Sanofi's additional questions.

        On December 23, 2017, our Board of Directors convened a telephonic meeting to discuss the Company's response to Sanofi's follow up requests and questions. During the course of this meeting, our Board of Directors instructed Mr. Cox to call Dr. Brandicourt directly to discuss the most efficient process for responding to the information requests. Our Board of Directors further discussed that while the Company was willing to provide further information to Sanofi, the Company was not engaging in negotiations with Sanofi regarding a potential transaction at such time.

        Between December 24, 2017 and January 3, 2018, representatives of Sanofi and the Company and, in certain instances, their respective financial advisors held a series of telephone calls with respect to Sanofi's follow-up requests arising out of the December 18, 2017 management presentation.

        On December 27, 2017, a representative of Lazard sent an email to representatives of J.P. Morgan and Guggenheim Securities to suggest scheduling a meeting between Mr. Posner and Mr. Weinberg. On December 29, 2017, a representative of Lazard also contacted Dr. Denner by telephone to suggest scheduling a meeting between the companies, including their respective chief executive officers, on January 3, 2018.

        On December 27, 2017, our Board of Directors convened a special telephonic meeting with certain members of senior management and a representative from Paul, Weiss joining a portion of the call. Mr. Cox provided an update on the Company's responses to Sanofi's ongoing diligence. Mr. Posner provided an update on discussions with Sanofi and its representatives that he had received from the Company's financial advisors. Our Board of Directors also discussed Sanofi's request for a meeting between the parties on January 3, 2018. During the course of this meeting, our Board of Directors asked numerous questions of the Company's senior management team relating to the assumptions underlying, and potential adjustments to the management projections and the expected risks to the Company's long-range plan as a standalone business. Our Board of Directors also discussed certain tax considerations relevant to any transaction involving the Company in light of the restrictions and obligations under the Tax Matters Agreement, including the requirement to provide Biogen with a copy of an "unqualified tax opinion" reasonably satisfactory to Biogen with respect to any transaction resulting in a change of control of the Company.

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        On December 29, 2017, Dr. Denner received an unsolicited call from a representative of Lazard, during which the representative from Lazard suggested that the Chief Executive Officers of each company meet in New York City on January 3, 2018.

        On December 30, 2017, our Board of Directors convened a special telephonic meeting with certain members of senior management and a representative of Paul, Weiss in attendance. During the meeting, our Board of Directors continued its discussion from its prior meeting and discussed the further request from the representative of Lazard for a meeting between the two companies. Following these discussions, our Board of Directors discussed that it would be willing to proceed with negotiations with Sanofi regarding a potential sale of the Company if Sanofi were prepared to make a sufficiently compelling offer, and authorized Mr. Cox, Dr. Denner and Mr. Posner to meet with Sanofi on January 3, 2018.

        On January 3, 2018, an in-person meeting was held in New York City at the offices of Weil, with Dr. Brandicourt and Mr. Weinberg (participating by videoconference) representing Sanofi, and Mr. Cox, Dr. Denner and Mr. Posner (participating by videoconference) representing the Company. In the course of this meeting, Sanofi verbally conveyed a revised offer price of $101.50 per Share in cash and emphasized that Sanofi believed this price represented a full valuation of the Company. Mr. Posner expressed his disappointment to Mr. Weinberg at the level of the offer. Mr. Weinberg indicated to Mr. Posner, Mr. Cox and Dr. Denner that he was disappointed in the Company's response and that he was going to find it very difficult to go back to the board of directors of Sanofi and request a higher price.

        On the evening of January 3, 2018, our Board of Directors held a special telephonic meeting, with representatives of J.P. Morgan, Guggenheim Securities and Paul, Weiss, and certain members of senior management in attendance for part of the meeting. The directors who were in attendance at the meeting with Sanofi provided an update to our Board of Directors of that meeting and discussion ensued between our Board of Directors and its outside legal and financial advisors. During the course of this meeting, the Chairman of our Board of Directors asked each member of our Board of Directors whether he or she would consider a sale of the Company at this time. Our Board of Directors also discussed the benefits to the Company of avoiding a protracted sale process that could potentially distract the management team at a critical time for the Company. Our Board of Directors also discussed the assumptions underlying, and potential adjustments to, the management projections as well as the risks associated with their achievement, including new competitive entrants, such as Hemlibra, and probabilities of pipeline successes. Representatives of J.P. Morgan and Guggenheim Securities reviewed a list of potential alternative acquirors and our Board of Directors discussed their belief that Sanofi was financially prepared given its cash on hand and its significant interest in developing the hemophilia business and its desire to expeditiously complete its diligence and execute a transaction. No decision was taken at this meeting and our Board of Directors agreed to reconvene the following day.

        On January 4, 2018, a special telephonic meeting of our Board of Directors was held with certain members of senior management and representatives of J.P. Morgan, Guggenheim Securities and Paul, Weiss also in attendance to continue the discussion from the January 3 meeting of our Board of Directors. During the course of this discussion, our Board of Directors concluded that it would be willing to proceed with negotiations for a sale of the Company at a price of $105.00 per Share in cash and that Dr. Denner was authorized to negotiate with representatives of Lazard, acting on behalf of Sanofi, to determine whether Sanofi was prepared to proceed on this basis.

        During the course of the January 4, 2018 meeting of our Board of Directors, Dr. Denner received a call from a representative of Lazard. In the course of this phone call, and consistent with instruction from our Board of Directors, Dr. Denner informed the representative of Lazard that the Company was prepared to move forward with discussions if Sanofi committed to a price of $105.00 per Share in cash. After checking with certain representatives from Sanofi, the representative from Lazard called

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Dr. Denner back and conveyed that Sanofi was prepared to move forward on that basis, but that Sanofi would require the Company to agree to a period of exclusivity through January 26, 2018, during which, among other things, the Company would be prohibited from soliciting alternative proposals from other parties.

        Immediately following his discussion with the representative of Lazard, Dr. Denner rejoined the January 4, 2018 meeting of our Board of Directors. Dr. Denner provided a summary of his discussion with the representative of Lazard and reviewed the terms of Sanofi's latest offer. Our Board of Directors then discussed the terms of Sanofi's latest non-binding offer with representatives of J.P. Morgan, Guggenheim Securities and Paul, Weiss, as well as certain members of senior management. Following this discussion, a representative of Paul, Weiss reviewed certain legal considerations in connection with evaluating the latest offer from Sanofi, including its request for a period of exclusivity, during which, among other things, the Company would be prohibited from soliciting alternative proposals from other parties. At the conclusion of the meeting, after careful consideration by our Board of Directors of the factors that our Board of Directors deemed relevant to its determination, including (i) the significant premium offered by Sanofi (and the fact that Sanofi's latest offer price was conditioned upon, among other things, an exclusivity period through January 26, 2018), (ii) the level of interest and engagement demonstrated by Sanofi to date, (iii) the proposed accelerated timeline to announce the transaction, (iv) the risk that Sanofi might decide not to proceed with a transaction if the Company did not commit to move forward on the terms proposed in Sanofi's January 4, 2018 offer, (v) the risk of a leak, particularly given the upcoming J.P. Morgan Healthcare Conference, and (vi) the fact that the anticipated terms of the proposed transaction would not make it difficult for other potential interested parties to submit a superior proposal during the pendency of the transaction, our Board of Directors resolved by vote to authorize the grant of exclusivity to Sanofi until January 26, 2018 and to authorize certain members of the Company's senior management and the Company's outside legal and financial advisors to proceed with negotiations with Sanofi regarding the proposed transaction.

        Following the meeting of our Board of Directors on January 4, 2018, representatives of the Company advised representatives of Sanofi that the Company was prepared to proceed with Sanofi on the basis of Sanofi's January 4, 2018 offer to acquire the Company at a price of $105.00 per Share payable in cash.

        Later on January 4, 2018, representatives of Weil circulated to representatives of Paul, Weiss a draft exclusivity agreement to be entered into by the Company. Paul, Weiss subsequently sent Weil its proposed revisions to such exclusivity agreement.

        On January 6, 2018, the Company and Sanofi entered into the Exclusivity Agreement (which was dated as of January 5, 2018), whereby the Company granted Sanofi a period of exclusivity until January 26, 2018, a copy of which is filed as Exhibit (e)(3) hereto and incorporated herein by reference. See "Item 3. Past Contacts, Transactions, Negotiations and Agreements—Arrangements with Purchaser and Parent and their Affiliates—Exclusivity Agreement."

        On January 8, 2018, the Company provided representatives of Sanofi with access to an electronic data room in connection with Sanofi's confirmatory due diligence review of the Company. Sanofi continued to perform due diligence through the data room and in meetings with certain Company representatives through the execution of the Merger Agreement.

        On January 11, 2018, Weil delivered an initial draft of the proposed Merger Agreement to Paul, Weiss.

        Over the next ten days, the Company, Sanofi, Paul, Weiss and Weil discussed the terms of the Transactions, including the size of the termination fee, the circumstances under which the Company could negotiate alternative proposals and accept superior offers, the steps necessary to ensure compliance with the terms of the Tax Matters Agreement, Sanofi's obligations to obtain required regulatory approvals, the representations and warranties and the interim operating restrictions.

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        During the period beginning January 12, 2018 and through the execution of the Merger Agreement, the Company held a number of diligence calls with Sanofi and its representatives on a variety of confirmatory matters, including the Company's human resources, manufacturing, research and development plans, medical and regulatory matters, tax compliance, operations and supply chain, finance, compliance, intellectual property and general legal matters.

        On January 15, 2018, our Board of Directors convened a meeting with certain members of senior management. Representatives of J.P. Morgan, Guggenheim Securities and Paul, Weiss were also in attendance. A representative of Paul, Weiss provided our Board of Directors with an update on the discussions with Sanofi, including the terms of the draft merger agreement. Our Board of Directors also discussed with members of senior management and the Company's legal and financial advisors a plan for contacting Biogen, which included a discussion of the Letter Agreement that would be sought to be entered into with Biogen and Sanofi relating to certain restrictions and obligations under the Tax Matters Agreement.

        On January 16, 2018, Paul, Weiss delivered comments on the draft Merger Agreement to Weil.

        On January 16, 2018, Paul, Weiss delivered to Weil a draft Letter Agreement addressing the Company's obligations under the Tax Matters Agreement to (i) provide Biogen with a copy of an "unqualified tax opinion" reasonably satisfactory to Biogen with respect to any transaction resulting in a change of control of the Company and (ii) indemnify Biogen in the event the proposed transaction caused the Spin-Off to fail to qualify as tax-free and Sanofi's agreement to guarantee the performance of such indemnity from and after the closing of the proposed transaction. During the course of the day of January 16, 2018 and into January 17, 2018, representatives from Paul, Weiss and Weil discussed and implemented changes to the initial draft Letter Agreement.

        On January 17, 2018, Mr. Cox contacted the Chief Executive Officer of Biogen regarding the potential transaction with Sanofi in order to discuss certain restrictions and limitations set forth in the Tax Matters Agreement. On January 17, 2018, the Company provided a draft of a Letter Agreement to Biogen, reflecting comments previously discussed between representatives from Paul, Weiss and Weil. The initial draft of the proposed Letter Agreement addressed the Company's obligations under the Tax Matters Agreement to provide Biogen with a copy of an "unqualified tax opinion" reasonably satisfactory to Biogen with respect to any transaction resulting in a change of control of the Company and to indemnify Biogen in the event the transaction caused the spinoff to not qualify as tax-free and a proposed guarantee of such indemnity by Sanofi from and after the closing of the proposed transaction. More specifically, the draft provided that the Company's obligations with respect to the execution and delivery of the Merger Agreement would be waived upon the delivery of an unqualified tax opinion prior to the execution of the Merger Agreement and would be waived with regard to closing of the Offer and Merger if a substantially similar tax opinion were delivered prior to the closing of the Offer and Merger. Between January 17, 2018, and the execution of the Merger Agreement, the Company, Biogen and Sanofi and their respective legal advisors exchanged various drafts of, and engaged in multiple negotiations related to, the Letter Agreement.

        Also, on January 17, 2018, Weil delivered a revised draft of the Merger Agreement to Paul, Weiss.

        On January 19, 2018, our Board of Directors held an in-person meeting with members of senior management that was also attended by representatives of J.P. Morgan, Guggenheim Securities and Paul, Weiss to discuss the outstanding terms of the Merger Agreement, the status of discussions with Sanofi related thereto and the status of discussions with Biogen and Sanofi with respect to the Letter Agreement. Management also presented updated projections as revised from its previous presentation on November 21, 2017. Our Board of Directors reviewed the terms of the Merger Agreement and the Letter Agreement, and focused in particular on provisions related to the termination fee, requesting that the Company attempt to lower the fee previously proposed by Sanofi. During the course of this meeting, a representative of Paul, Weiss reviewed with our Board of Directors their fiduciary duties

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under applicable law and representatives from J.P. Morgan, Guggenheim Securities and Paul, Weiss discussed the financial and legal terms of the current draft of the Merger Agreement.

        During the period from January 19, 2018 to January 21, 2018, the parties and their respective representatives continued to negotiate the terms of the draft agreements and exchanged several drafts of the Merger Agreement. In this same period, the Company and Sanofi exchanged drafts of the Letter Agreement with Biogen.

        On January 20, 2018, the Company entered into an engagement letter with Guggenheim Securities, and on January 21, 2018, the Company entered into an engagement letter with J.P. Morgan, effective as of November 15, 2017, pursuant to which each of J.P. Morgan and Guggenheim Securities, respectively, would be formally engaged as outside financial advisor in connection with the proposed transaction. See "Item 5. Person/Assets Retained, Employed, Compensated or Used."

        On January 21, 2018, a special telephonic meeting of our Board of Directors was held, which was also attended by representatives of senior management and representatives of J.P. Morgan, Guggenheim Securities and Paul, Weiss. At this meeting, a representative from Paul, Weiss reminded our Board of Directors of their fiduciary duties under applicable law and reviewed with our Board of Directors the terms of the Merger Agreement, focusing on certain changes to the terms discussed at the meeting of our Board of Directors on January 19, 2018.

        Each of J.P. Morgan and Guggenheim Securities then reviewed with our Board of Directors their respective financial analysis of the $105.00 per Share cash consideration to be paid in the Transactions to the holders of Shares pursuant to the Merger Agreement, which was consistent with the financial analysis that each of J.P. Morgan and Guggenheim Securities, respectively, had delivered to our Board of Directors at the meeting on January 19, 2018. Each of J.P. Morgan and Guggenheim Securities then rendered an oral opinion, which was subsequently confirmed by delivery of a written opinion from each of J.P. Morgan and Guggenheim Securities, each dated January 21, 2018, that, as of such date and based upon and subject to the various assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken by each of J.P. Morgan and Guggenheim Securities in preparing each of their respective written opinions, as set forth in each such opinion, the Offer Price to be paid pursuant to the Merger Agreement was fair, from a financial point of view, to the holders of Shares (in their capacity as such and other than Shares owned by Parent and Merger Sub) (see "—Opinions of Financial Advisors").

        After further discussing potential reasons for and against the proposed transaction including our Board of Directors' analysis of the possible alternatives to the proposed transactions, including continuing to operate as a standalone business, and the risks associated with such possible alternatives (see below under the heading "—Reasons for Recommendation"), our Board of Directors unanimously adopted resolutions (i) declaring that the Merger Agreement, the Merger and the other Transactions, including the Offer, are advisable, fair to, and in the best interests of, the Company and its stockholders, (ii) adopting and approving the Merger Agreement, the entry by the Company into the Merger Agreement, and the consummation of the Transactions, including the Offer and the Merger, (iii) recommending that the Company's stockholders (other than Parent and its Subsidiaries) accept the Offer and tender their Shares to Purchaser pursuant to the Offer, (iv) resolving to take all actions necessary so that the restrictions on business combinations and stockholder vote requirements contained in Section 203 of the DGCL and any other applicable law with respect to a "moratorium," "control share acquisition," "business combination," "fair price" or other forms of anti-takeover laws or regulations that may purport to be applicable will not apply with respect to or as a result of the Merger, the Merger Agreement and the Transactions (including the Offer) and (v) agreeing and authorizing that the Merger be governed by Section 251(h) of the DGCL and consummated as soon as practicable following the consummation of the Offer.

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        Following the meeting of our Board of Directors on January 21, 2018, the Company, Sanofi, Paul, Weiss and Weil finalized the terms of the Merger Agreement. During the evening of January 21, 2018, the Company, Sanofi and Merger Sub executed and delivered the Merger Agreement. Simultaneously with the execution of the Merger Agreement, the Company, Sanofi and Biogen executed and delivered the Letter Agreement. Simultaneously with the execution of the Merger Agreement, Paul, Weiss delivered the tax opinion contemplated by the Tax Matters Agreement and the Letter Agreement to the Company and, a copy of such opinion was provided to each of Biogen and Sanofi.

        On the morning of January 22, 2018, prior to the opening of trading of the Shares on the NASDAQ, Sanofi and the Company issued a joint press release announcing the execution of the Merger Agreement and the forthcoming commencement of the Offer to acquire all of the outstanding Shares at a price of $105.00 per Share in cash. The joint press release is included as Exhibit (a)(7) hereto and is incorporated herein by reference.

        On February 7, 2018, Merger Sub commenced the Offer and the Company filed this Schedule 14D-9.

(iii)

Reasons for Recommendation

        Our Board of Directors consulted with senior management of the Company regarding, among other things, the Company's industry, and its business and prospects as an independent company. Our Board of Directors consulted with its financial advisors regarding the financial aspects of the Transactions, as well as the fairness, from a financial point of view, to the Company's stockholders of the consideration to be received by such stockholders pursuant to the Transactions. Our Board of Directors also consulted with its legal counsel regarding the Board of Directors' legal duties, the terms of the Merger Agreement and related issues. In the course of reaching its unanimous determination, our Board of Directors carefully considered numerous factors, including the following non-exhaustive list of material factors and benefits that weighed positively in favor of its unanimous decision, among others and not necessarily in order of relative importance:

•

Premium to Market Price.   Our Board of Directors considered:



•

the current and historical market prices of the Shares, including the market performance of the Shares relative to those of other participants in the Company's industry and general market indices, and the fact that the Offer Price represents a compelling premium to historical market prices of the Shares, including (1) a 63.8% premium to the closing price of the Shares on January 19, 2018, the last full trading day prior to the public announcement of the transaction; (2) a 79.0% premium to the 30-day volume weighted average price (" VWAP ") for the Shares; (3) a 92.7% premium to the 60-day VWAP for the Shares; (4) a 83.6% premium to the closing price of the Shares on November 2, 2017, the last full trading day prior to Parent's initial offer of $98.50 per Share; and (5) a 89.6% premium to the closing price of the Shares on January 3, 2018, the last full trading day prior to the parties' agreement on the Offer Price of $105.00 per Share;



•

the fact that the Company negotiated an increase in the consideration payable in the Offer to $105.00 per Share from Sanofi's initial proposal of $98.50 per Share on November 3, 2017; and



•

the fact that since the Company's initial separation from Biogen on February 1, 2017, the per-Share trading price of the Shares has never exceeded the level of the Offer Price.



•

Cash Tender Offer; Certainty of Value.   Our Board of Directors considered that the Offer Price is all cash and that under the DGCL the second-step merger can be completed immediately following the consummation of the Offer, without a vote of the Company's stockholders, so that the Transactions provide certainty, immediate value and liquidity to our stockholders for their

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Shares, especially when viewed against any internal or external risks and uncertainties associated with the Company's standalone strategy.

•

The Company's Operating and Financial Condition; Prospects of the Company.   Our Board of Directors considered the Company's business, financial condition and results of operations and concluded that the Offer Price is more favorable to the Company's stockholders in the short term than the potential value that could be expected to be generated were the Company to remain independent and execute on its current business and financial plans. Our Board of Directors considered, among other factors, that its stockholders would continue to be subject to the risks and uncertainties of the Company if it remained independent. These execution risks and uncertainties included risks relating to revenue concentration and dependency on the Company's products, ELOCTATE and ALPROLIX; potential failure to compete effectively with other hemophilia treatments; potential difficulties and delays in clinical trials of product candidates; regulatory developments involving current and future products and product candidates; and other risks and uncertainties, including the risk factors set forth in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2016 and subsequent quarterly reports on Form 10-Q.



•

Potentially Interested Counterparties.   Our Board of Directors considered, after discussions with J.P. Morgan and Guggenheim Securities and senior management, that (i) a broader outreach to potential acquirors could delay a potential transaction and cause significant disruption at a critical stage of the Company's development, putting at risk a transaction with Sanofi at the price negotiated, (ii) other potential partners had not approached the Company to inquire about a strategic transaction with the Company and (iii) should any such potential counterparty be interested in pursuing a transaction on terms more favorable to the Company and its stockholders than those contemplated by the Merger Agreement, such counterparty would be able to pursue such an offer for the Company despite Sanofi and the Company having entered into the Merger Agreement.



•

Fairness Opinions.   The opinions, dated January 21, 2018, of each of J.P. Morgan and Guggenheim Securities to our Board of Directors as to the fairness, from a financial point of view and as of the date of the opinion, of the Offer Price to be paid to the Company's stockholders (in their capacity as such and other than Sanofi and Merger Sub), which opinion was based on and subject to the matters considered, the procedures followed, the assumptions made and various limitations of and qualifications to the review undertaken as more fully described under the section entitled " —Opinions of Bioverativ's Financial Advisors " below. The full text of the written opinions of J.P. Morgan and Guggenheim Securities have been included as Annex I and Annex II, respectively, to this Schedule 14D-9 and are incorporated herein by reference.



•

Likelihood and Speed of Consummation.   Our Board of Directors considered the likelihood of completion of the Transactions to be high, particularly in light of the terms of the Merger Agreement and the closing conditions to the Offer and the Merger, including:



•

the conditions to the Offer and the Merger being specific and limited;



•

the size and financial strength of Parent;



•

the likelihood of obtaining required regulatory approvals, and the commitments Sanofi agreed to in the Merger Agreement regarding regulatory approvals;



•

the remedy of specific performance available to the Company under the Merger Agreement in the event of breaches by Parent and Purchaser;

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•

the fact that the Offer and the Merger are not subject to the conditionality and execution risk of any required approval by Parent's stockholders; and



•

the structure of the transaction as a cash tender offer for all outstanding Shares, with the expected result that a relatively short period will elapse before our stockholders receive the Offer Price, followed by the Merger under Section 251(h) of the DGCL, which would not require Company stockholder approval, and in which stockholders who do not validly exercise appraisal rights will receive the same consideration received by those stockholders who tender their Shares in the Offer. Our Board of Directors considered that the potential for closing in a relatively short time frame could also reduce the amount of time during which the Company's business would be subject to the potential uncertainty of closing and related disruption.



•

Product Development and Regulatory Risks. Our Board of Directors considered that clinical trials can take years to complete, and the outcomes are uncertain. In addition to the risks inherent in the development and eventual commercialization of the Company's product candidates, our Board of Directors also considered the risks related to market acceptance of product candidates, if approved, and other factors affecting the revenues and profitability of biopharmaceutical product candidates generally.



•

Product Launch and Commercialization Risks and Costs. Our Board of Directors assessed the significant risks and considerable costs associated with a successful launch and commercialization by the Company of its product candidates that would impact the Company's prospects for substantially increasing stockholder value as a standalone company in excess of the Offer Price, given the risks and uncertainties in its business, including, among other things, the costs and risks associated with continuing the development of other pipeline drug candidates or acquisition of other commercial or pipeline assets; risks relating to competition from existing drugs and drugs under development; and risks relating to commercial drug sales.



•

Expansion Risk. The Company plans to expand the marketing of its two products into additional geographies. Regulators of other jurisdictions have their own procedures for approval of product candidates. Our Board of Directors considered that even if a product is approved, regulators may limit the indications for which the product may be marketed, require extensive warnings on the product labeling or require expensive and time-consuming clinical trials or reporting as conditions of approval. Our Board of Directors considered the risks inherent in obtaining regulatory approvals from regulatory authorities in additional jurisdictions to be able to sell the Company's products in such jurisdictions, which can take years to complete and the receipt of which are not guaranteed; the capital required to complete the regulatory approval processes; the timing and cost of product commercialization activities, including marketing and distribution arrangements, should the regulatory approvals be received; and the potential for revenue generation and profitability of the two products if sold in additional jurisdictions.



•

Best Strategic Alternative for Maximizing Stockholder Value.   Our Board of Directors determined, after a thorough review of strategic alternatives and discussions with our management and its financial and legal advisors, that the Offer Price is more favorable to the Company's stockholders in the short term than the potential value that might have resulted from other strategic options available, including, but not limited to, remaining a standalone public company.



•

Negotiation Process.   Our Board of Directors considered the enhancements that the Company and its advisors were able to obtain as a result of robust arm's-length negotiations with Parent, including the increase in the Offer Price proposed by Parent from the time of its initial indication of interest to the end of the negotiations, and the inclusion of provisions in the Merger Agreement that increase the likelihood of completing the Offer and consummating the Merger.

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•

No Financing Condition.   The Board considered the fact that Parent and Purchaser would have sufficient cash resources to pay the amounts required to be paid under the Merger Agreement without obtaining third-party financing and that the Transaction is not subject to a financing condition.



•

Industry and Economy.   Our Board of Directors considered the current state of the economy and assessed the stage of the pharmaceutical industry cycle, financing markets, uncertainty in drug pricing and uncertainty surrounding forecasted economic conditions both in the near term and the long term, generally and within the Company's industry in particular, in addition to other geopolitical risk considerations.



•

Certain Management Projections.   Our Board of Directors considered certain forecasts for the Company prepared by senior management of the Company, which reflected certain assumptions of the Company's senior management, including product revenue growth and future economic, competitive and regulatory conditions. For further discussion, see "—Certain Unaudited Prospective Financial Information."



•

Opportunity to Receive Unsolicited Proposals, Change Recommendation or Terminate the Transactions in Order to Accept a Superior Proposal.   Our Board of Directors considered the terms of the Merger Agreement permitting the Company to receive unsolicited proposals, and the other terms and conditions of the Merger Agreement, including:



•

that the Company may, subject to certain conditions, furnish, pursuant to entry into an acceptable confidentiality agreement, confidential information with respect to the Company and its subsidiaries and access thereto to third parties making such an unsolicited proposal and participate or engage in negotiations or discussions with such third parties regarding unsolicited proposals that are made prior to the time that the Offer is consummated;



•

the provisions of the Merger Agreement allowing our Board of Directors in certain circumstances to terminate the Merger Agreement in order to enter into a definitive agreement with respect to an unsolicited superior proposal, subject to payment of a termination fee of $326 million, which amount the directors believed to be reasonable under the circumstances and taking into account the range of such termination fees in similar transactions, and the unlikelihood that a fee of such size would be a meaningful deterrent to other acquisition proposals. Our Board of Directors also recognized that the provisions in the Merger Agreement relating to this fee were insisted on by Sanofi as a condition to entering into the Merger Agreement; and



•

its ability under the Merger Agreement to withdraw or modify its recommendation that the Company's stockholders tender their Shares to Purchaser pursuant to the Offer in certain circumstances, including in connection with a superior proposal or an event, occurrence or fact occurring or arising after the date of the Merger Agreement that was not known to our Board of Directors as of the date of the Merger Agreement.



•

Other Terms of the Merger Agreement.   Our Board of Directors considered other terms of the Merger Agreement, as more fully described in Section 11—"The Merger Agreement; Other Agreements" of the Offer to Purchase. Certain provisions of the Merger Agreement that the Board of Directors considered important included:



•

Termination Date.   The termination date under the Merger Agreement on which either Parent or the Company, subject to certain exceptions, can terminate the Merger Agreement, which is anticipated to allow for sufficient time to obtain required regulatory approvals and to consummate the Offer and the Merger while minimizing the length of time during which the Company would be required to operate subject to the restrictions on interim operations set forth in the Merger Agreement.

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•

Cooperation.   The Merger Agreement requires Parent and Purchaser to use their reasonable best efforts to consummate the Offer and the Merger.



•

Extension of the Offer.   Merger Sub's obligation to accept and pay for all Shares that have been validly tendered into the Offer and not validly withdrawn is subject to the satisfaction or waiver of a number of conditions. However, Sanofi and Merger Sub are required to extend the Offer beyond the initial Expiration Time if, at any otherwise scheduled Expiration Time (as such terms are defined in "Section 11—"Purpose of the Offer and Plans for Bioverativ; Summary of the Merger Agreement and Certain Other Agreements" in the Offer to Purchase), any condition has not been satisfied or waived, for up to 10 business days per extension (but not beyond the earlier to occur of (i) the valid termination of the Merger Agreement and (ii) the End Date (as such term is defined in "Section 11—"Purpose of the Offer and Plans for Bioverativ; Summary of the Merger Agreement and Certain Other Agreements" in the Offer to Purchase)).



•

Company Material Adverse Effect.   Our Board of Directors considered the provisions in the Merger Agreement that, among other things, specify that, subject to the terms of the Merger Agreement, any state of facts, circumstance, condition, event, change, development, occurrence, result or effect resulting from (i) the public announcement or pendency of the Transactions, including, in each case, the impact thereof on relationships, contractual or otherwise, with customers, suppliers, vendors, lenders, investors, licensors, licensees, venture partners or employees, (ii) changes in conditions generally affecting the industry in which the Company and the Company Subsidiaries operate (unless such changes have a disproportionate adverse impact on the Company and its subsidiaries as compared to any other participants in the industries in which the Company and its subsidiaries operate), (iii) the failure by the Company or any of the Company Subsidiaries to meet any internal or external projections or forecasts or any decline in the price of Shares, are excluded from the determination of whether a Company Material Adverse Effect (as defined and more fully described "Section 11—"Purpose of the Offer and Plans for Bioverativ; Summary of the Merger Agreement and Certain Other Agreements" in the Offer to Purchase) has occurred that would permit Sanofi to elect not to consummate the Offer.



•

Appraisal Rights.   Our Board of Directors considered the availability of statutory appraisal rights to the Company's stockholders who do not tender their Shares in the Offer and otherwise comply with all required procedures for demanding appraisal under the DGCL.

        Our Board of Directors also considered a variety of risks and other potentially adverse factors in determining whether to approve the Merger Agreement and the Transactions and recommend that stockholders tender their Shares pursuant to the Offer, including the following, which are not necessarily listed in order of relative importance:

•

the fact that the Company would no longer exist as an independent, publicly traded company, and the Company's stockholders would no longer have the opportunity to participate in any potential future earnings or growth of the Company or benefit from the successful execution of the Company's current strategy as a public company;



•

the fact that the Merger Agreement precludes the Company from actively soliciting alternative transaction proposals and restricts the Company's ability to engage in discussions regarding unsolicited alternative transaction proposals unless, subject to certain terms and conditions in the Merger Agreement, the Board of Directors determines, in good faith, a proposal constitutes or would be reasonably likely to constitute a superior proposal to the Transactions;

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•

the possibility that under certain circumstances, the Company may be required to pay Parent a termination fee of $326 million, including if the Company terminates the Merger Agreement to accept a superior proposal or the Board of Directors changes its recommendation;



•

the potential risk of diverting management attention and resources from the operation of the Company's business and towards completion of the Offer and the Merger;



•

the risk of incurring substantial expenses related to the Offer and the Merger;



•

the risk that all conditions to the parties' obligations to complete the Offer and the Merger are not satisfied, and as a result, the Merger is not completed;



•

the risks and costs to the Company if the Transactions do not close, including uncertainty about the effect of the proposed Offer and Merger on the Company's employees, customers and key relationships, which may impair the Company's ability to attract, retain and motivate key personnel, and could cause customers, suppliers and others to seek to change existing business relationships with the Company;



•

the possibility that another party might have been willing to pay a higher purchase price for the Company than the Offer Price;



•

the possibility that, although the Offer and the Merger provide the Company's stockholders the opportunity to realize a premium to the price at which the Shares traded prior to the public announcement of the proposed transaction, the price of the Shares might have increased in the future to a price greater than the Offer Price;



•

the potential conflict of interest created by the fact that the Company's executive officers and directors have financial interests in the Offer and the Merger that may be different from, or in addition to, those of other stockholders, as more fully described in "Item 3. Past Contacts, Transactions, Negotiations and Agreements—Arrangements between the Company and its Executive Officers, Directors and Affiliates."



•

the fact that the gain realized by the Company's stockholders as a result of the Offer and the Merger generally will be taxable to the stockholders for U.S. federal income tax purposes;



•

the restrictions in the Merger Agreement on the conduct of the Company's business prior to the consummation of the Merger, which may delay or prevent the Company from undertaking business or other opportunities that may arise prior to the consummation of the Offer or the Merger;



•

the potential effect of the public announcement of the Merger Agreement, including effects on the Company's revenues, customers, operating results and share price and the Company's ability to attract and retain key management and personnel; and



•

the risk of litigation in connection with the execution of the Merger Agreement, the completion of the Offer and the consummation of the Merger.

        Our Board of Directors concluded that the risks, uncertainties, restrictions and potentially negative reasons associated with the Offer and Merger were outweighed by the potential benefits of the Offer and Merger. Our Board of Directors collectively reached the unanimous conclusion to approve the Merger Agreement and the Transactions in light of these various factors.

        The foregoing discussion of our Board of Directors' reasons for its recommendation to accept the Offer is not meant to be exhaustive, but addresses the material information and factors considered by our Board of Directors in connection with its recommendation. In view of the wide variety of reasons considered by our Board of Directors in connection with the evaluation of the Offer and the complexity of these matters, our Board of Directors did not find it practicable to, and did not, quantify or

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otherwise assign relative weights to the specific reasons considered in reaching its determination and recommendation. Rather, our directors made their determinations and recommendations based on the totality of the information presented to them, and the judgments of individual members of our Board of Directors may have been influenced to a greater or lesser degree by different reasons.

        The foregoing description of the consideration by our Board of Directors of the reasons supporting the Merger Agreement, the Offer, the Merger and the other Transactions contemplated by the Merger Agreement and its recommendation that stockholders tender their Shares pursuant to the Offer is forward-looking in nature. This information should be read in light of the factors discussed in the section entitled " Cautionary Note Regarding Forward-Looking Statements ."

(iv)

Certain Unaudited Prospective Financial Information

        The Company does not, as a matter of course, publicly disclose forecasts or projections as to future performance, earnings or other results (with the exception of limited near-term guidance with respect to total revenue growth, operating margin and tax rate) due to the inherent unpredictability of projections and their underlying assumptions and estimates. However, in connection with the Transactions, senior management prepared certain internal financial analyses and forecasts relating to the long-term plan as a standalone company (the " Management Projections "). The Management Projections were provided to J.P. Morgan and Guggenheim Securities solely in connection with the rendering of their fairness opinions to our Board of Directors and performing their related financial analysis, as described above under the heading "—Opinions of Financial Advisors."

        The Management Projections are probability-adjusted and took into account certain financial, operating and commercial assumptions developed solely using the information available to our management at the time the Management Projections were created. Senior management assumed probabilities of success of products currently under development, considering certain assumptions that senior management believed to be common in the industry for assessing risks associated with development and commercialization.

        A summary of the Management Projections is set forth below: