THRY Thryv Holdings Inc

The selling stockholders named in this prospectus are offering 4,238,426 shares of our common stock, par value $0.01 per share (“common stock”). We will not receive any proceeds from the sale of the shares by the selling stockholders, but we have agreed to pay certain registration expenses, other than commissions or discounts of underwriters, broker-dealers, or agents.

Our common stock is listed on The Nasdaq Capital Market (“Nasdaq”) under the symbol “THRY”. On May 25, 2021, the closing price of our common stock as reported on Nasdaq was $25.22 per share.

In reviewing this prospectus, you should carefully consider the matters described under the caption “Risk Factors” beginning on page 4, as well as the risk factors and other information contained in our Annual Report on Form 10-K for the year ended December 31, 2020 and our Quarterly Report on Form 10-Q for the quarter ended March 31, 2021, which are incorporated by reference into this prospectus.

The selling stockholders have granted the underwriters an option to purchase up to 635,763 additional shares of common stock at the public offering price less the underwriting discount for a period of 30 days from the date of this prospectus.

The underwriters expect to deliver the shares of common stock to purchasers on or about June 1, 2021.

Neither the Securities and Exchange Commission (“SEC”) nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Pursuant to Rule 429 under the Securities Act of 1933, as amended (the “Securities Act”), this prospectus is a combined prospectus relating to 4,874,189 shares of common stock offered by the selling stockholders that are currently registered and remain outstanding under Registration No. 333-256294 that we filed with the SEC.

You should rely only on the information contained in this prospectus. See “Where You Can Find More Information.”

Neither we, the selling stockholders nor the underwriters have authorized anyone to provide any information other than that contained in this prospectus or in any free writing prospectus prepared by or on behalf of us or to which we may have referred you. Neither we, the selling stockholders, nor the underwriters take any responsibility for, nor can we or they provide assurance as to the reliability of, any other information that others may give you. Neither we, the selling stockholders nor the underwriters have authorized any other person to provide you with different or additional information, and neither we nor they are making an offer to sell the shares in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus is accurate only as of the date on the front cover of this prospectus, regardless of the time of delivery of the prospectus or any sale of the common stock. Our business, financial condition, results of operations and prospects may have changed since the date on the front cover of this prospectus.

For investors outside of the United States, neither we, the selling stockholders, nor the underwriters have done anything that would permit the offering or possession or distribution of this prospectus in any jurisdiction where action for that purpose is required, other than in the United States. You are required to inform yourselves about and to observe any restrictions relating to the offering and the distribution of this prospectus outside of the United States.

The forward-looking statements included in this prospectus and the documents incorporated by reference into this prospectus are made only as of the date hereof and thereof. You should not rely upon forward-looking statements as predictions of future events. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee that the future results, levels of activity, performance or events and circumstances reflected in the forward-looking statements will be achieved or occur. Moreover, neither we nor any other person assumes responsibility for the accuracy and completeness of the forward-looking statements. We undertake no obligation to update publicly any forward-looking statements for any reason after the date of this prospectus or the documents incorporated by reference into this prospectus to conform these statements to actual results or to changes in our expectations, except as may be required by law.

You should read this prospectus and the documents incorporated by reference into this prospectus with the understanding that our actual future results, levels of activity, performance and events and circumstances may be materially different from what we expect.

In addition, stock markets have experienced price and volume fluctuations that have affected and continue to affect the market prices of equity securities of many companies. Stock prices of many companies have fluctuated in a manner often unrelated to the operating performance of those companies. These fluctuations may be even more pronounced in the trading market for our common stock as a result of the supply and demand forces described above. In the past, stockholders have instituted securities class action litigation following periods of market volatility. If we were to become involved in securities litigation, it could subject us to substantial costs, divert resources and the attention of management from our business and harm our business, results of operations and financial condition.

Our common stock is listed and traded on Nasdaq. Prior to listing on Nasdaq on October 1, 2020, there had been no public market for our common stock and there had not been a sustained history of trading in our common stock in “over-the-counter” markets. While our common stock may currently be sold by the selling stockholders pursuant to the Registration Statement or by our other existing stockholders in accordance with Rule 144 of the Securities Act of 1933, as amended, or the Securities Act, there can be no assurance that any selling stockholders or other existing stockholders will sell any of their shares of common stock and there may be, from time to time, a lack of supply of, or demand for, common stock on Nasdaq. Conversely, the selling stockholders and other existing stockholders may sell all of their shares of common stock, resulting in an oversupply of our common stock on Nasdaq. In the case of a lack of supply of our common stock, the trading price of our common stock may rise to an unsustainable level. Further, institutional investors may be discouraged from purchasing our common stock if they are unable to purchase a block of our common stock in the open market due to a potential unwillingness of our existing stockholders to sell a sufficient amount of common stock at the price offered by such institutional investors and the greater influence individual investors have in setting the trading price. If institutional investors are unable to purchase our common stock, the market for our common stock may be” more volatile without the influence of long-term institutional investors holding significant amounts of our common stock. In the case of a lack of market demand for our common stock, the trading price of our common stock could decline significantly and rapidly. Furthermore, the decision by Mudrick Capital, who retains significant ownership of our common stock, to sell, or refrain from selling, shares of common stock from time to time, could impact the market supply and trading volumes of our common stock, thereby affecting market prices and creating additional volatility, which impact will increase if the percentage of shares sold by non-affiliated stockholders or other existing stockholders from time to time decreases. Therefore, an active, liquid and orderly trading market for our common stock may not be sustained, which could significantly depress the public price of our common stock and/or result in significant volatility, which could affect your ability to sell your shares of common stock.

As of May 17, 2021, we had outstanding warrants to purchase an aggregate of 5,253,850 shares of our common stock at an exercise price of $24.39 per share. The warrants may be exercised in whole or in part at any time prior to their expiration at 5:00 p.m., Pacific Time, on August 15, 2023. To the extent such warrants are exercised, additional shares of our common stock will be issued, which will result in dilution to the holders of our common stock and increase the number of shares eligible for resale in the public market. Resales of substantial numbers of shares

in the public market in close proximity to the day that our shares of common stock are initially listed on Nasdaq may increase price volatility which could adversely affect the price of our common stock.

As of May 17, 2021, Mudrick Capital beneficially owned and controlled common stock representing approximately 49.7% of the voting power of our outstanding common stock. As a result of this ownership or control of our voting securities, Mudrick Capital will significant influence over the outcome of certain matters submitted to our stockholders for approval, including the election of directors. This may delay or prevent an acquisition or cause the public price of our common stock to decline. Mudrick Capital may have interests different from yours. Therefore, the concentration of voting power by Mudrick Capital may have an adverse effect on the price of our common stock.

Growth forecasts are subject to significant uncertainty and are based on assumptions and estimates which may not prove to be accurate. Our forecasts, if any, relating to the expected growth in marketing and management software markets may prove to be inaccurate. Even if these markets experience such forecasted growth, we may not grow our business at similar rates, or at all. Our growth is subject to many factors, including our success in implementing our business strategy, which is subject to many risks and uncertainties. Accordingly, our forecasts of market growth should not be taken as necessarily indicative of our future growth.

The trading market for our common stock will depend in part on the research and reports that securities or industry analysts publish about us and/or our business. Securities and industry analysts do not currently and may never, publish research on our company. If few securities analysts commence coverage of us, or if industry analysts cease coverage of us, the trading price for our common stock would be adversely affected. If one or more of the analysts who cover us downgrade our common stock or publish inaccurate or unfavorable research about our business, our common stock price would likely decline. If one or more of these analysts cease coverage of us or fail to publish reports on us on a regular basis, demand for our common stock could decrease, which might cause our common stock price and trading volume to decline.

deferring, or preventing a change in control of our company without further action by the stockholders and may adversely affect the voting and other rights of the holders of our common stock. Our Board has not authorized the issuance of any shares of preferred stock, and we have no agreements or plans for the issuance of any shares of preferred stock.

On August 15, 2016, we entered into a Warrant Agreement by and among us, Computershare, Inc. and Computershare Trust Company, N.A. (as amended, the “Warrant Agreement”). The Warrant Agreement governs the terms and rights of our warrants to purchase shares of common stock at the applicable exercise price of such warrants. Each warrant represents the right to purchase one share of common stock at an initial exercise price of $24.39 per share. As of May 17, 2021, 9,456,931 warrants were outstanding and holders of such warrants are entitled to purchase, in the aggregate, up to 5,253,850 shares of common stock.

The warrants may be exercised in whole or in part at any time prior to the expiration time of 5:00 p.m. Pacific time on August 15, 2023. The warrants may be exercised upon delivery of a duly completed exercise notice on or prior to the expiration time at the offices of the warrant agent, accompanied by full payment of the exercise price for the number of warrants being exercised and a duly executed joinder to the Company’s Amended and Restated Stockholder’s Agreement.

No fractional shares will be issued upon the exercise of the warrants. If, upon exercise of the warrants, a holder would be entitled to receive a fractional interest in a share of common stock, we will, upon exercise, round down to the nearest whole number the number of shares of common stock to be issued to the warrant holder in accordance with the terms of the Warrant Agreement.

Each warrant not exercised prior to the expiration time shall become void, and all rights of the warrant holder under the Warrant Agreement shall cease. If a sale of the Company (as defined in the Warrant Agreement) is consummated prior to the expiration time in which 100% of the consideration paid to or received by non-employee holders of common stock in such sale of the Company consists of cash and the sale price is less than or equal to the exercise price on the date the sale of the Company is consummated, each warrant not exercised at or before that date shall also become void.

The warrant holders do not have the rights or privileges of holders of common stock including, without limitation, the right to vote or to consent or to receive notice as a stockholder in respect of any meeting of stockholders for the election of directors of the Company or any other matter, to receive dividends on warrant shares or any rights whatsoever as stockholders of the Company, until such warrant is duly exercised in accordance with the Warrant Agreement and such warrant holder is issued shares of common stock in connection therewith.

The warrants are transferable, provided that such transfer (i) would be permitted under the terms of our Amended and Restated Stockholders’ Agreement if such warrant constituted shares of common stock and (ii) is not made to a competitor without approval of our Board. The warrants are not transferable, however, if as a result of the transfer, the warrants would be held of record by 1,980 or more persons or 480 or more persons who are not “accredited investors”, or otherwise in circumstances that our Board determines would require us to file reports under the Exchange Act if we are not otherwise subject to such requirements.

The terms of the warrants may be amended, modified or waived by us together with the affirmative vote or consent of the majority holders of the warrants then outstanding; provided that if (i) the exercise price would be increased and/or the number of warrant shares would be decreased (other than pursuant to the adjustment) or (ii) the

expiration time is modified to occur earlier, then the consent of each warrant holder affected thereby is required. We and the warrant agent, however, may supplement or amend the Warrant Agreement as necessary without the approval of the warrant holders to cure any ambiguity or mistake so long as such amendment does not adversely affect, alter or change the interests of any warrant holder.

Our fourth amended and restated certificate of incorporation and second amended and restated bylaws contain provisions that delay, defer, or discourage transactions involving an actual or potential change in control of us or change in our management. These provisions, which are summarized below, discourage coercive takeover practices or inadequate takeover bids. These provisions are be designed to encourage persons seeking to acquire control of us to first negotiate with our Board, which we believe may result in an improvement of the terms of any such acquisition in favor of our stockholders. However, they also give our Board the power to discourage transactions that some stockholders may favor, including transactions in which stockholders might otherwise receive a premium for their shares or transactions that our stockholders might otherwise deem to be in their best interests. Accordingly, these provisions could adversely affect the price of our common stock.

Our fourth amended and restated certificate of incorporation provides that our Board will be divided into three classes, Class I, Class II and Class III, with members of each class serving staggered three-year terms. Our fourth amended and restated certificate of incorporation provides that the number of directors constituting the entire board may be changed only by the board of directors. Any additional directorships resulting from an increase in the number of directors will be distributed among the three classes so that, as nearly as possible, each class will consist of one-third of the directors. Our second amended and restated bylaws also provides that a director may be removed by the affirmative vote of the holders of a majority of our outstanding shares of capital stock entitled to vote generally in the election of directors, and only for cause. Any vacancy on our Board, including a vacancy resulting from an enlargement of our Board, may be filled only by the vote of a majority of our directors then in office. Our classified Board could have the effect of delaying or discouraging an acquisition of us or a change in our management.

Our second amended and restated bylaws provides that special meetings of the stockholders may be called upon the request of a majority of our Board, the Chairman of our Board or the President and our Chief Executive Officer. Our second amended and restated bylaws prohibit the conduct of any business at a special meeting other than as specified in the notice for such meeting. These provisions may have the effect of deferring, delaying or discouraging hostile takeovers or changes in control or management of our company.

Our second amended and restated bylaws establish advance notice procedures with respect to stockholder proposals and the nomination of candidates for election as directors, other than nominations made by or at the direction of our Board or a committee of our Board. In order for any matter to be “properly brought” before a meeting, a stockholder will have to comply with the advance notice requirements of directors, which may be filled only by a vote of a majority of directors then in office, even though less than a quorum, and not by the stockholders. Our second amended and restated bylaws allows the chairman of any meeting of stockholders to determine the order of business and the procedure at the meeting, including such regulation of the manner of voting and the conduct of discussion, which may have the effect of precluding the conduct of certain business at a meeting if the rules and regulations are not followed. These provisions may also defer, delay or discourage a potential acquirer from conducting a solicitation of proxies to elect the acquirer’s own slate of directors or otherwise attempting to obtain control of our company.

Our fourth amended and restated certificate of incorporation and our second amended and restated bylaws provide that after the time that Mudrick Capital and its affiliates collectively own less than 40% of our then outstanding common stock, subject to the rights of any holders of preferred stock to act by written consent instead of a meeting, stockholder action may be taken only at an annual meeting or special meeting of stockholders and may not be taken by written consent instead of a meeting. Failure to satisfy any of the requirements for a stockholder meeting could delay, prevent or invalidate stockholder action.

Our fourth amended and restated certificate of incorporation provides that the provisions of Section 203 of the DGCL, which relate to business combinations with interested stockholders, do not apply to us. Section 203 of the DGCL prohibits a publicly held Delaware corporation from engaging in a business combination transaction with an interested stockholder (a stockholder who owns more than 15% of our common stock) for a period of three years after the interested stockholder became such unless the transaction fits within an applicable exemption, such as Board approval of the business combination or the transaction that resulted in such stockholder becoming an interested stockholder. These provisions apply even if the business combination could be considered beneficial by some stockholders. Our fourth amended and restated certificate of incorporation contains provisions that have the same effect as Section 203 of the DGCL but provides that Mudrick Capital and any of its affiliates or successors, and any group as to which such persons are party do not constitute interested stockholders for purposes of these provisions for so long as they collectively own, directly or indirectly, 10% or more of the voting power of our then outstanding shares of voting stock. Although we have elected to opt out of the statute’s provisions, we could elect to be subject to Section 203 in the future.

Any amendment to our fourth amended and restated certificate of incorporation must first be approved by a majority of our Board and, if required by law, thereafter be approved by a majority of the outstanding shares entitled to vote on the amendment voting as a single class. Our second amended and restated bylaws may be amended (x) by the affirmative vote of a majority of the directors then in office, subject to any limitations set forth in the bylaws, without further stockholder action or (y) by the affirmative vote of at least a majority of the outstanding shares entitled to vote on the amendment, voting as a single class, without further action by our Board.

Our fourth amended and restated certificate of incorporation provides that, we renounce any interest or expectancy in, or in being offered an opportunity to participate in, any business opportunity that may from time to time be presented to Mudrick Capital, Paulson or GoldenTree or any of their respective affiliates (including, but not limited to, any entity that, directly or indirectly, controls, is controlled by or is under common control with it and including, in the case of Paulson, any individual nominated by Paulson and appointed as a director of the Board as of the date of the fourth amended and restated certificate of incorporation), successors, directly or indirectly managed funds or vehicles, partners, principals, directors, officers, members, managers and employees (other than our company and its subsidiaries) (“Exempted Persons”), even if the opportunity is one that we might reasonably have pursued or had the ability or desire to pursue if granted the opportunity to do so. No such Exempted Persons will be liable to us for breach of any fiduciary or other duty, as a director or officer or otherwise, by reason of the fact that such person pursues or acquires any such business opportunity, directs any such business opportunity to another person or fails to present any such business opportunity, or information regarding any such business opportunity, to us. None of the Exempted Persons has any fiduciary duty to refrain from engaging directly or indirectly in the same or similar business activities or lines of business as us or any of our subsidiaries.

Our second amended and restated bylaws provide, subject to limited exceptions, that the Court of Chancery of the State of Delaware will, to the fullest extent permitted by law, be the sole and exclusive forum for (i) any derivative action or proceeding brought on our behalf; (ii) any action asserting a claim of breach of a fiduciary duty owed by any of our directors, officers or other employees to us or our stockholders; (iii) any action asserting a claim against us, any director or our officers or employees arising pursuant to any provision of the DGCL, our fourth amended and restated certificate of incorporation or our second amended and restated bylaws; or (iv) any action asserting a claim against us, any director or our officers or employees that are governed by the internal affairs doctrine. This exclusive forum provision does not apply to claims arising under the Securities Act, the Exchange Act or other federal securities laws and rules and regulations promulgated thereunder for which there is exclusive federal or concurrent federal and state jurisdiction. The federal district courts of the United States of America shall be the sole and exclusive forum for the resolution of any action asserting a claim arising under the Securities Act, the Exchange Act or the rules and regulations promulgated thereunder, and investors cannot waive compliance with the federal securities laws and the rules and regulations thereunder. Any person or entity purchasing or otherwise acquiring any interest in shares of our capital stock shall be deemed to have notice of and to have consented to the provisions of our fourth amended and restated certificate of incorporation described above.

Our common stock listed on Nasdaq under the symbol “THRY”.

The transfer agent and registrar for our common stock is Computershare Inc.

THIS DISCUSSION IS FOR INFORMATIONAL PURPOSES ONLY AND IS NOT TAX ADVICE. INVESTORS CONSIDERING THE PURCHASE, OWNERSHIP AND DISPOSITION OF OUR COMMON STOCK ARE URGED TO CONSULT THEIR OWN TAX ADVISORS REGARDING THE APPLICATION OF U.S. FEDERAL INCOME TAX LAWS TO THEIR PARTICULAR SITUATIONS AND THE CONSEQUENCES OF OTHER FEDERAL, STATE, LOCAL AND FOREIGN TAX LAWS, AND APPLICABLE TAX TREATIES.

If we pay distributions on shares of our common stock, such distributions will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Distributions in excess of our current and accumulated earnings and profits will constitute a return of capital that is applied against and reduces, but not below zero, a non-U.S. holder’s adjusted tax basis in shares of our common stock. Any remaining excess will be treated as gain realized on the sale or other taxable disposition of our common stock. See “— Dispositions of Common Stock.”

Subject to the discussion below regarding effectively connected income, any dividend paid to a non-U.S. holder on our common stock will generally be subject to U.S. federal withholding tax at a 30% rate. The withholding tax might not apply, however, or might apply at a reduced rate, under the terms of an applicable income tax treaty. You are urged to consult your own tax advisor regarding your entitlement to benefits under a relevant income tax treaty. Generally, in order for the applicable withholding agent to withhold tax at a lower treaty rate, a non-U.S. holder must certify its entitlement to treaty benefits. A non-U.S. holder generally can meet this certification requirement by providing a valid Internal Revenue Service (the “IRS”) Form W-8BEN or IRS Form W-8BEN-E (or other applicable form or documentation), as applicable, to the applicable withholding agent. If the non-U.S. holder holds the stock through a financial institution or other agent acting on the non-U.S. holder’s behalf, the non-U.S. holder will be required to provide appropriate documentation to the agent. Even if our current or accumulated earnings or profits are less than the amount of the distribution, the applicable withholding agent may elect to treat the entire distribution as a dividend for U.S. federal withholding tax purposes. A non-U.S. holder that does not timely furnish the required documentation, but that qualifies for a reduced treaty rate, may obtain a refund of any excess amounts withheld by timely filing an appropriate claim for refund with the IRS.

Dividends received by a non-U.S. holder that are effectively connected with a U.S. trade or business conducted by the non-U.S. holder and, if required by an applicable income tax treaty, are attributable to a permanent establishment (or, in certain cases involving individual holders, a fixed base) maintained by the non-U.S. holder in the U.S., are generally not subject to such withholding tax. To obtain this exemption, a non-U.S. holder must provide the applicable withholding agent with a valid IRS Form W-8ECI properly certifying such exemption. Such effectively connected dividends, although not subject to withholding tax (provided certain certification and disclosure requirements are satisfied), are taxed at the same regular rates applicable to U.S. persons, net of certain deductions and credits. In addition to the regular tax described above, such effectively connected dividends, subject to certain adjustments, received by corporate non-U.S. holders may also be subject to a branch profits tax at a rate of 30% or such lower rate as may be specified by an applicable income tax treaty.

The foregoing discussion is subject to the discussion below under “— Backup Withholding and Information Reporting” and “— Other Withholding Taxes.”

Subject to the discussion below on backup withholding and other withholding requirements, gain realized by a non-U.S. holder on a sale, exchange or other taxable disposition of our common stock generally will not be subject to U.S. federal income or withholding tax, unless:

Generally, a corporation is a USRPHC if the fair market value of its “United States real property interests” equals 50% or more of the sum of the fair market value of (a) its worldwide real property interests and (b) its other assets used or held for use in a trade or business. The tax relating to the sale or other taxable disposition of stock in a USRPHC does not apply to a non-U.S. holder whose holdings, actual and constructive, amount to 5% or less of our common stock at all times during the shorter of the five-year period ending on the date of the sale or other taxable disposition or the non-U.S. Holder’s holding period for our common stock, provided that our common stock is regularly traded on an established securities market. No assurance can be provided that our common stock will be regularly traded on an established securities market at all times for purposes of the rules described above. Although there can be no assurances in this regard, we believe we have not been and are not currently a USRPHC, and do not anticipate being a USRPHC in the future. You are urged to consult your own tax advisor about the consequences that could result if we are, or become, a USRPHC.

If any gain from the sale, exchange or other taxable disposition of our common stock, (1) is effectively connected with a U.S. trade or business conducted by a non-U.S. holder and (2) if required by an applicable income tax treaty, is attributable to a permanent establishment (or, in certain cases involving individuals, a fixed base) maintained by such non-U.S. holder in the U.S., then the gain generally will be subject to U.S. federal income tax at the same regular rates applicable to U.S. persons, net of certain deductions and credits. If the non-U.S. holder is a corporation, under certain circumstances, such effectively connected gain, subject to certain adjustments, generally would also be subject to a “branch profits tax.” The branch profits tax rate is generally 30%, although an applicable income tax treaty might provide for a lower rate.

Any distributions on our common stock to a non-U.S. holder must be reported annually to the IRS and to the non-U.S. holder, regardless of whether such distributions constitute dividends or whether any tax was actually withheld. Copies of these information returns also may be made available to the tax authorities of the country in which the non-U.S. holder resides under the provisions of various treaties or agreements for the exchange of information. Dividends paid on our common stock and the gross proceeds from a sale or other taxable disposition of our common stock may be subject to additional information reporting and may also be subject to U.S. federal backup withholding if such non-U.S. holder fails to comply with applicable U.S. information reporting and certification requirements. Provision of an IRS Form W-8 appropriate to the non-U.S. holder’s circumstances will generally satisfy the certification requirements necessary to avoid the additional information reporting and backup withholding.

Backup withholding is not an additional tax. Any amounts so withheld under the backup withholding rules will be refunded by the IRS or credited against the non-U.S. holder’s U.S. federal income tax liability, provided that the required information is timely furnished to the IRS.

Provisions commonly referred to as “FATCA” impose withholding (separate and apart from, but without duplication of, the withholding tax described above) at a rate of 30% on payments of U.S.-source dividends (including our dividends) paid to “foreign financial institutions” (which is broadly defined for this purpose and in general includes investment vehicles) and certain other non-U.S. entities unless various U.S. information reporting and due diligence requirements (generally relating to ownership by U.S. persons of interests in or accounts with those entities) have been satisfied, or an exemption applies. Withholding imposed by FATCA may also apply to gross proceeds from the sale or other disposition of domestic corporate stock (including our stock); although, under proposed U.S. Treasury Regulations published on December 18, 2018, no withholding under FATCA would apply to

such gross proceeds. The preamble to the proposed U.S. Treasury regulations specifies that taxpayers (including withholding agents) are permitted to rely on the proposed U.S. Treasury regulations pending finalization. An intergovernmental agreement between the U.S. and an applicable foreign country may modify these requirements. Accordingly, the entity through which our common stock is held will affect the determination of whether such withholding is required. If FATCA withholding is imposed, a beneficial owner that is not a foreign financial institution generally will be entitled to a refund of any amounts withheld by filing a U.S. federal income tax return containing the required information (which may entail significant administrative burden). Non-U.S. holders are urged to consult their own tax advisors regarding the effects of FATCA on their investment in our common stock.

THE PRECEDING DISCUSSION OF U.S. FEDERAL INCOME TAX CONSIDERATIONS IS FOR GENERAL INFORMATION ONLY. IT IS NOT TAX ADVICE. EACH PROSPECTIVE INVESTOR IS URGED TO CONSULT ITS OWN TAX ADVISOR REGARDING THE PARTICULAR U.S. FEDERAL, STATE, LOCAL AND FOREIGN TAX CONSEQUENCES OF PURCHASING, OWNING AND DISPOSING OF OUR COMMON STOCK, INCLUDING THE CONSEQUENCES OF ANY PROPOSED CHANGE IN APPLICABLE LAWS AND TREATIES.

We have agreed with the underwriters, through and including the date that is 60 days after the date of this prospectus and subject to specified exceptions, not to (i) offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise transfer or dispose of, directly or indirectly, or file with the SEC a registration statement under the Securities Act relating to, any shares of our common stock or any securities that are substantially similar to our common stock, including but not limited to any options or warrants to purchase shares of our common stock or any securities that are convertible into or exchangeable for, or that represent the right to receive, common stock or any such substantially similar securities, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of our common stock, or any such other securities, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of our common stock or such other securities, in cash or otherwise, without the prior written consent of William Blair & Company, L.L.C.

Our directors, executive officers and the selling stockholders have agreed with the underwriters not to (i) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, make any short sale or otherwise transfer or dispose of, directly or indirectly, any shares of our common stock or any securities convertible into, exercisable or exchangeable for or that represent the right to receive our common stock (including without limitation, our common stock which may be deemed to be beneficially owned in accordance with the rules and regulations of the SEC and securities which may be issued upon exercise of a stock option or warrant), whether now owned or hereafter acquired, (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of our common stock, whether any such transaction is to be settled by delivery of our common stock or such other securities, in cash or otherwise (iii) make any demand for, or exercise any right with respect to registration under the Securities Act of our common stock or any security convertible into or exercisable or exchangeable for our common stock, or (iv) publicly disclose the intention to do any of the foregoing. These restrictions will apply through and including the date that is 60 days after the date of this prospectus. The restrictions described above are subject to certain customary exceptions for transfers, including exceptions related to open market transactions, the establishment of Rule 10b5-1 plans, bona fide gifts, certain transfers to trusts, partnerships, limited liability companies and other entities, certain affiliate transfers, transfers to the company pursuant to repurchase arrangements or transfers pursuant to any third-party tender offer or similar transaction. The lock-up agreement also permits the pledge, hypothecation, or grant and any related transfer of such shares in connection with any margin loan or other loans, advances and extensions of credit.

Our common stock is listed on Nasdaq under the symbol “THRY.”

Until the distribution of the shares is completed, SEC rules may limit the underwriters and selling group members from bidding for and purchasing shares of our common stock. However, the underwriters may engage in transactions that stabilize the price of our common stock, such as bids or purchases to peg, fix or maintain that price.

In connection with this offering, the underwriters may purchase and sell shares of our common stock in the open market. These transactions may include short sales, purchases on the open market to cover positions created by short sales and stabilizing transactions. Short sales involve the sale by the underwriters of a greater number of shares than they are required to purchase in this offering. “Covered” short sales are sales made in an amount not greater than the underwriters’ option to purchase additional shares described above. The underwriters may close out any covered short position by either exercising this option or purchasing shares in the open market. In determining the source of shares to close out the covered short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase shares through this option. “Naked” short sales are sales in excess of this option. The underwriters must close out any naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of our common stock in the open market after pricing that could adversely affect investors who purchase in this offering. Stabilizing transactions consist of various bids for or purchases of shares of our common stock made by the underwriters in the open market prior to the closing of this offering.

The representative may also impose a penalty bid. This occurs when a particular underwriter is required to repay to the representative a portion of the underwriting discount received by it because the representative has repurchased shares sold by or for the account of such underwriter in stabilizing or short covering transactions.

Similar to other purchase transactions, the underwriters’ purchases to cover short sales may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of our common stock. As a result, the price of our common stock may be higher than the price that might otherwise exist in the open market. The underwriters may conduct these transactions on The Nasdaq Capital Market, in the over-the-counter market or otherwise.

Neither we nor the underwriters make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of our common stock. In addition, neither we nor the underwriters make any representation that the underwriters will engage in these transactions or that these transactions, once commenced, will not be discontinued without notice.

In connection with this offering, the underwriters or securities dealers may distribute prospectuses by electronic means, such as e-mail. In addition, the underwriters may facilitate Internet distribution for this offering to certain of their Internet subscription customers. The underwriters may allocate a limited number of shares for sale to its online brokerage customers. An electronic prospectus is available on the Internet websites maintained by the underwriters. The information on the websites of such underwriters is not part of this prospectus.

The underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. The underwriters and their respective affiliates may engage in from time to time in the future certain investment banking and other commercial dealings in the ordinary course of business with us or our affiliates, for which they have received and may continue to receive customary fees and commissions. In the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers, and such investment and securities activities may involve securities and/or instruments of the issuer.

The underwriters and their respective affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

In relation to each Member State of the European Economic Area (each an “EEA State”), no shares of common stock have been offered or will be offered pursuant to the offering to the public in that EEA State prior to the publication of a prospectus in relation to the shares of common stock which has been approved by the competent authority in that EEA State or, where appropriate, approved in another EEA State and notified to the competent authority in that EEA State, all in accordance with the EU Prospectus Regulation, except that it may make an offer to the public in that EEA State of any shares of common stock at any time under the following exemptions under the EU Prospectus Regulation:

For the purposes of this provision, the expression an “offer to the public” in relation to any shares of common stock in any Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the shares of common stock to be offered so as to enable an investor to decide to purchase or subscribe the units, and the expression “EU Prospectus Regulation” means Regulation (EU) 2017/1129 (as amended or superseded).

In relation to the United Kingdom, no shares have been offered or will be offered pursuant to the offering to the public in the United Kingdom prior to the publication of a prospectus in relation to the shares of common stock which has been approved by the Financial Conduct Authority in accordance with the UK Prospectus Regulation, except that it may make an offer to the public in the United Kingdom of any shares of common stock at any time under the following exemptions under the UK Prospectus Regulation:

provided that no such offer of the shares of common stock shall require the company or any underwriter to publish a prospectus pursuant to Article 3 of the UK Prospectus Regulation or supplement a prospectus pursuant to Article 23 of the UK Prospectus Regulation.

In the United Kingdom, the offering is only addressed to, and is directed only at, “qualified investors” within the meaning of Article 2(e) of the UK Prospectus Regulation, who are also (i) persons having professional experience in matters relating to investments who fall within the definition of “investment professionals” in Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005 (the “Order”); (ii) high net worth bodies corporate, unincorporated associations and partnerships and trustees of high value trusts as described in Article 49(2) of the Order; or (iii) persons to whom it may otherwise lawfully be communicated (all such persons being referred to as “relevant persons”). This document must not be acted on or relied on by persons who are not relevant persons. Any investment or investment activity to which this document relates is available only to relevant persons and will be engaged in only with relevant persons.

For the purposes of this provision, the expression an “offer to the public” in relation to the shares of common stock in the United Kingdom means the communication in any form and by any means of sufficient information on the terms of the offering and any shares of common stock to be offered so as to enable an investor to decide to purchase or subscribe for any shares of common stock, and the expression “UK Prospectus Regulation” means the UK version of Regulation (EU) No 2017/1129 as amended by The Prospectus (Amendment etc.) (EU Exit) Regulations 2019, which is part of UK law by virtue of the European Union (Withdrawal) Act 2018.

Neither this prospectus nor any other offering material relating to the units described in this prospectus has been submitted to the clearance procedures of the Autorité des Marchés Financiers or by the competent authority of another member state of the European Economic Area and notified to the Autorité des Marchés Financiers. The units have not been offered or sold and will not be offered or sold, directly or indirectly, to the public in France. Neither this prospectus nor any other offering material relating to the units has been or will be:

Such offers, sales and distributions will be made in France only:

The units may be resold directly or indirectly, only in compliance with articles L.411-1, L.411-2, L.412- 1 and L.621-8 through L.621-8-3 of the French Code monétaire et financier.

The units may not be offered or sold in Hong Kong by means of any document other than (i) in circumstances which do not constitute an offer to the public within the meaning of the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32, Laws of Hong Kong), or (ii) to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder, or (iii) in other circumstances which do not result in the document being a “prospectus” within the meaning of the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32, Laws of Hong Kong) and no advertisement, invitation or document relating to the units may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the laws of Hong Kong) other than with respect to units which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder.

The shares may not be publicly offered in Switzerland and will not be listed on the SIX Swiss Exchange (“SIX”) or on any other stock exchange or regulated trading facility in Switzerland. This document has been prepared without regard to the disclosure standards for issuance prospectuses under art. 652a or art. 1156 of the Swiss Code of Obligations or the disclosure standards for listing prospectuses under art. 27 ff. of the SIX Listing Rules or the listing rules of any other stock exchange or regulated trading facility in Switzerland. Neither this document nor any other offering or marketing material relating to the shares or the offering may be publicly distributed or otherwise made publicly available in Switzerland.

Neither this document nor any other offering or marketing material relating to the offering, the Company, the shares have been or will be filed with or approved by any Swiss regulatory authority. In particular, this document will not be filed with, and the offer of shares will not be supervised by, the Swiss Financial Market Supervisory Authority FINMA (FINMA), and the offer of shares has not been and will not be authorized under the Swiss Federal Act on Collective Investment Schemes (“CISA”). The investor protection afforded to acquirers of interests in collective investment schemes under the CISA does not extend to acquirers of shares.

The shares of common stock may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the shares of common stock must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus (including any amendment or supplement thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 (or, in the case of securities issued or guaranteed by the government of a non-Canadian jurisdiction, section 3A.4) of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

No placement document, prospectus, product disclosure statement or other disclosure document has been lodged with the Australian Securities and Investments Commission (“ASIC”), in relation to the offering. This prospectus does not constitute a prospectus, product disclosure statement or other disclosure document under the Corporations Act 2001 (the “Corporations Act”), and does not purport to include the information required for a prospectus, product disclosure statement or other disclosure document under the Corporations Act.

Any offer in Australia of the shares of common stock may only be made to persons (the “Exempt Investors”) who are “sophisticated investors” (within the meaning of section 708(8) of the Corporations Act), “professional investors” (within the meaning of section 708(11) of the Corporations Act) or otherwise pursuant to one or more exemptions contained in section 708 of the Corporations Act so that it is lawful to offer the shares of common stock without disclosure to investors under Chapter 6D of the Corporations Act.

The shares of common stock applied for by Exempt Investors in Australia must not be offered for sale in Australia in the period of 12 months after the date of allotment under the offering, except in circumstances where disclosure to investors under Chapter 6D of the Corporations Act would not be required pursuant to an exemption under section 708 of the Corporations Act or otherwise or where the offer is pursuant to a disclosure document which complies with Chapter 6D of the Corporations Act. Any person acquiring shares of common stock must observe such Australian on-sale restrictions.

This prospectus contains general information only and does not take account of the investment objectives, financial situation or particular needs of any particular person. It does not contain any securities recommendations or financial product advice. Before making an investment decision, investors need to consider whether the information in this prospectus is appropriate to their needs, objectives and circumstances, and, if necessary, seek expert advice on those matters.

The shares of common stock have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (Law No. 25 of 1948, as amended) and, accordingly, will not be offered or sold, directly or indirectly, in Japan, or for the benefit of any Japanese Person or to others for re-offering or resale, directly or indirectly, in Japan or to any Japanese Person, except in compliance with all applicable laws, regulations and ministerial guidelines promulgated by relevant Japanese governmental or regulatory authorities in effect at the relevant time. For the purposes of this paragraph, “Japanese Person” shall mean any person resident in Japan, including any corporation or other entity organized under the laws of Japan.

This prospectus has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, the shares of common stock were not offered or sold or caused to be made the subject of an invitation for subscription or purchase and will not be offered or sold or caused to be made the subject of an invitation for subscription or purchase, and this prospectus or any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the shares of common stock, has not been circulated or distributed, nor will it be circulated or distributed, whether directly or indirectly, to any person in Singapore other than (i) to an institutional investor (as defined in Section 4A of the Securities and Futures Act (Chapter 289) of Singapore, as modified or amended from time to time (the “SFA”)) pursuant to Section 274 of the SFA, (ii) to a relevant person (as defined in Section 275(2) of the SFA) pursuant to Section 275(1) of the SFA, or any person pursuant to Section 275(1A) of the SFA, and in accordance with the conditions specified in Section 275 of the SFA, or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where the shares of common stock are subscribed or purchased under Section 275 of the SFA by a relevant person which is:

securities or securities-based derivatives contracts (each term as defined in Section 2(1) of the SFA) of that corporation or the beneficiaries’ rights and interest (howsoever described) in that trust shall not be transferred within six months after that corporation or that trust has acquired the shares of common stock pursuant to an offer made under Section 275 of the SFA except:

In connection with Section 309B of the SFA and the Capital Markets Products (the “CMP”) Regulations 2018, the shares of common stock are prescribed capital markets products (as defined in the CMP Regulations 2018) and Excluded Investment Products (as defined in Monetary Authority of Singapore Notice SFA 04-N12: Notice on the Sale of Investment Products and Monetary Authority of Singapore Notice FAA-N16: Notice on Recommendations on Investment Products).