UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.    )

Filed by the Registrant  ☒                            Filed by a Party other than the Registrant  ☐

Check the appropriate box:

Cogent Biosciences, Inc.

(Name of Registrant as Specified in Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

200 Cambridge Park Drive, Suite 2500, Cambridge, Massachusetts 02140

NOTICE OF THE 2022 ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON JUNE 7, 2022

To the Stockholders of Cogent Biosciences, Inc.:

Cogent Biosciences, Inc. (the “Company”) will hold its 2022 Annual Meeting of Stockholders (the “Annual Meeting”) on Tuesday, June 7, 2022, at 9:00 a.m. Eastern Time. The Annual Meeting will be a virtual meeting conducted exclusively online via live audio webcast at www.virtualshareholdermeeting.com/COGT2022. The Annual Meeting will be held for the following purposes, as more fully described in the accompanying proxy statement (the “Proxy Statement”):

The Board of Directors has fixed April 19, 2022 as the record date. Only stockholders of record at the close of business on that date will be entitled to notice of, and to vote at, the Annual Meeting or any adjournment or postponement thereof.

Instructions for accessing the virtual Annual Meeting are provided in the Proxy Statement. In the event of a technical malfunction or other situation that the meeting chair determines may affect the ability of the Annual Meeting to satisfy the requirements for a meeting of stockholders to be held by means of remote communication under the Delaware General Corporation Law, or that otherwise makes it advisable to adjourn the Annual Meeting, the meeting chair or secretary will convene the meeting at 10:00 a.m. Eastern Time on the date specified above and at the Company’s address specified above solely for the purpose of adjourning the meeting to reconvene at a date, time and physical or virtual location announced by the meeting chair or secretary. Under either of the foregoing circumstances, we will post information regarding the announcement on the Investors page of the Company’s website at https://investors.cogentbio.com/.

Whether or not you expect to participate in the virtual Annual Meeting, please vote as promptly as possible in order to ensure your representation at the Annual Meeting. You may vote online or, if you requested printed copies of the proxy materials, by telephone or by using the proxy card or voting instruction form provided with the printed proxy materials.

TABLE OF CONTENTS

LEGAL MATTERS

Important Notice Regarding the Availability of Proxy Materials for the 2022 Annual Meeting of Stockholders to Be Held on June 7, 2022. The Proxy Statement and Annual Report for the year ended December 31, 2021 are available at www.proxyvote.com.

Forward-Looking Statements. The Proxy Statement may contain “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, which statements are subject to substantial risks and uncertainties and are based on estimates and assumptions. All statements, other than statements of historical facts, included in the Proxy Statement are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as “may,” “might,” “will,” “objective,” “intend,” “should,” “could,” “can,” “would,” “expect,” “believe,” “design,” “estimate,” “predict,” “potential,” “plan” or the negative of these terms, and similar expressions intended to identify forward-looking statements. These statements involve known and unknown risks, uncertainties and other factors that could cause our actual results to differ materially from the forward-looking statements expressed or implied in the Proxy Statement. Such risks, uncertainties and other factors include those identified in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 filed with the U.S. Securities and Exchange Commission (“SEC”) and other subsequent documents we file with the SEC. The Company expressly disclaims any obligation to update or alter any statements whether as a result of new information, future events or otherwise, except as required by law.

Website References. Website references throughout this document are inactive textual references and provided for convenience only, and the content on the referenced websites is not incorporated herein by reference and does not constitute a part of the Proxy Statement.

200 Cambridge Park Drive, Suite 2500, Cambridge, Massachusetts 02140

PROXY STATEMENT

FOR THE 2022 ANNUAL MEETING OF STOCKHOLDERS

QUESTIONS AND ANSWERS ABOUT THE PROXY MATERIALS AND VOTING

What Is the Purpose of These Proxy Materials?

We are making these proxy materials available to you in connection with the solicitation of proxies by the Board of Directors (the “Board”) of Cogent Biosciences, Inc. (“we,” “us,” “our” or the “Company”) for use at the 2022 Annual Meeting of Stockholders (the “Annual Meeting”) to be held virtually on June 7, 2022 at 9:00 a.m. Eastern Time, or at any other time following adjournment or postponement thereof. You are invited to participate in the Annual Meeting and to vote on the proposals described in this Proxy Statement. The proxy materials are first being made available to our stockholders on or about April 26, 2022.

Why Did I Receive a Notice of Internet Availability?

Pursuant to U.S. Securities and Exchange Commission (“SEC”) rules, we are furnishing the proxy materials to our stockholders primarily via the Internet instead of mailing printed copies. This process allows us to expedite our stockholders’ receipt of proxy materials, lower the costs of printing and mailing the proxy materials and reduce the environmental impact of our Annual Meeting. If you received a Notice of Internet Availability of Proxy Materials (the “Notice”), you will not receive a printed copy of the proxy materials unless you request one. The Notice provides instructions on how to access the proxy materials for the Annual Meeting via the Internet, how to request a printed set of proxy materials and how to vote your shares.

Why Are We Holding a Virtual Annual Meeting?

We have adopted a virtual meeting format for the Annual Meeting to provide a consistent experience to all stockholders regardless of geographic location. We believe this expands stockholder access, improves communications and lowers our costs while reducing the environmental impact of the meeting. Utilizing a virtual meeting format also helps to protect our stockholders and employees in light of the public health and safety considerations posed by the ongoing coronavirus (COVID-19) pandemic. In structuring our virtual Annual Meeting, our goal is to enhance rather than constrain stockholder participation in the meeting, and we have designed the meeting to provide stockholders with the same rights and opportunities to participate as they would have at an in-person meeting.

Who Can Vote?

Only stockholders of record at the close of business on April 19, 2022 (the “Record Date”) are entitled to notice of the Annual Meeting and to vote on the proposals described in this Proxy Statement. At the close of business on the Record Date, 45,819,266 shares of our common stock were issued and outstanding.

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What Is the Difference between Holding Shares as a Registered Stockholder and as a Beneficial Owner?

Registered Stockholder: Shares Registered in Your Name

If your shares of common stock are registered directly in your name with our transfer agent, Computershare Trust Company, N.A., you are considered to be, with respect to those shares of common stock, the registered stockholder, and these proxy materials are being sent directly to you by us.

Beneficial Owner: Shares Registered in the Name of a Broker, Fiduciary or Custodian

If your shares of common stock are held by a broker, fiduciary or custodian, you are considered the beneficial owner of shares of common stock held in “street name,” and these proxy materials are being forwarded to you from that broker, fiduciary or custodian.

How Can I Participate in the Virtual Annual Meeting?

Stockholders of record as of the close of business on the record date are entitled to participate in and vote at the Annual Meeting. To participate in the Annual Meeting, including to vote, ask questions and view the list of registered stockholders as of the record date during the meeting, stockholders of record should go to the meeting website at www.virtualshareholdermeeting.com/COGT2022, enter the 16-digit control number found on your proxy card or Notice, and follow the instructions on the website. If your shares are held in street name and your voting instruction form or Notice indicates that you may vote those shares through www.proxyvote.com, then you may access, participate in and vote at the Annual Meeting with the 16-digit access code indicated on that voting instruction form or Notice. Otherwise, stockholders who hold their shares in street name should contact their bank, broker or other nominee (preferably at least five days before the Annual Meeting) and obtain a “legal proxy” in order to be able to attend, participate in or vote at the Annual Meeting.

We will endeavor to answer as many stockholder-submitted questions as time permits that comply with the Annual Meeting rules of conduct. We reserve the right to edit profanity or other inappropriate language and to exclude questions regarding topics that are not pertinent to meeting matters or Company business. If we receive substantially similar questions, we may group such questions together and provide a single response to avoid repetition.

The meeting webcast will begin promptly at 9:00 a.m. Eastern Time. Online check-in will begin approximately 15 minutes before then, and we encourage you to allow ample time for check-in procedures. If you experience technical difficulties during the check-in process or during the meeting, please call the number listed on the meeting website for technical support. Additional information regarding the rules and procedures for participating in the Annual Meeting will be set forth in our meeting rules of conduct, which stockholders can view during the meeting at the meeting website.

What Am I Voting on?

The proposals to be voted on at the Annual Meeting are as follows:

How Does the Board Recommend That I Vote?

The Board recommends that you vote your shares “FOR” each director nominee in Proposal 1 and “FOR” Proposal 2.

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What If Another Matter Is Properly Brought before the Annual Meeting?

As of the date of filing this Proxy Statement, the Board knows of no other matters that will be presented for consideration at the Annual Meeting. If any other matters are properly brought before the Annual Meeting, it is the intention of the persons named as proxies in the proxy card to vote on such matters in accordance with their best judgment.

How Many Votes Do I Have?

Each share of common stock is entitled to one vote on each proposal to be voted on at the Annual Meeting.

What Does It Mean If I Receive More Than One Set of Proxy Materials?

If you receive more than one set of proxy materials, your shares may be registered in more than one name or held in different accounts. Please cast your vote with respect to each set of proxy materials that you receive to ensure that all of your shares are voted.

How Do I Vote?

Even if you plan to attend the Annual Meeting, we recommend that you also submit your vote as early as possible in advance so that your vote will be counted if you later decide not to, or are unable to, virtually attend the Annual Meeting.

Registered Stockholder: Shares Registered in Your Name

If you are the registered stockholder, you may vote your shares online during the virtual Annual Meeting (see “How Can I Participate in the Virtual Annual Meeting?” above) or by proxy in advance of the Annual Meeting by Internet (at www.proxyvote.com) or, if you requested paper copies of the proxy materials, by completing and mailing a proxy card or by telephone (at (800) 690-6903).

Beneficial Owner: Shares Registered in the Name of a Broker, Fiduciary or Custodian

If you are the beneficial owner, you may vote your shares online during the virtual Annual Meeting (see “How Can I Participate in the Virtual Annual Meeting?” above) or you may direct your broker, fiduciary or custodian how to vote in advance of the Annual Meeting by following the instructions they provide.

What Happens If I Do Not Vote?

Registered Stockholder: Shares Registered in Your Name

If you are the registered stockholder and do not vote in one of the ways described above, your shares will not be voted at the Annual Meeting and will not be counted toward the quorum requirement.

Beneficial Owner: Shares Registered in the Name of a Broker, Fiduciary or Custodian

If you are the beneficial owner and do not direct your broker, fiduciary or custodian how to vote your shares, your broker, fiduciary or custodian will only be able to vote your shares with respect to proposals considered to be “routine” (which we expect includes Proposal 2). Your broker, fiduciary or custodian is not entitled to vote your shares with respect to “non-routine” proposals (which we expect includes Proposal 1), which we refer to as a “broker non-vote.” Whether a proposal is considered routine or non-routine is subject to stock exchange rules and final determination by the stock exchange. Even with respect to routine matters, some brokers are choosing not to exercise discretionary voting authority. As a result, we urge you to direct your broker, fiduciary or custodian how to vote your shares on all proposals to ensure that your vote is counted.

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What If I Sign and Return a Proxy Card or Otherwise Vote but Do Not Indicate Specific Choices?

Registered Stockholder: Shares Registered in Your Name

The shares represented by each signed and returned proxy will be voted at the Annual Meeting by the persons named as proxies in the proxy card in accordance with the instructions indicated on the proxy card. However, if you are the registered stockholder and sign and return your proxy card without giving specific instructions, the persons named as proxies in the proxy card will vote your shares in accordance with the recommendations of the Board. Your shares will be counted toward the quorum requirement.

Beneficial Owner: Shares Registered in the Name of a Broker, Fiduciary or Custodian

If you are the beneficial owner and sign and return your voting instruction form without giving specific instructions, your broker, fiduciary or custodian will only be able to vote your shares with respect to proposals considered to be “routine.” Your broker, fiduciary or custodian is not entitled to vote your shares with respect to “non-routine” proposals, resulting in a broker non-vote with respect to such proposals.

Can I Change My Vote after I Submit My Proxy?

Registered Stockholder: Shares Registered in Your Name

If you are the registered stockholder, you may revoke your proxy at any time before the final vote at the Annual Meeting in any one of the following ways:

(4) You may vote by attending the Annual Meeting virtually. However, your virtual attendance at the Annual Meeting will not, by itself, revoke your proxy.

Your last submitted vote is the one that will be counted.

Beneficial Owner: Shares Registered in the Name of a Broker, Fiduciary or Custodian

If you are the beneficial owner, you must follow the instructions you receive from your broker, fiduciary or custodian with respect to changing your vote.

What Is the Quorum Requirement?

The holders of a majority of the shares of common stock outstanding and entitled to vote at the Annual Meeting must be present at the Annual Meeting, either virtually or represented by proxy, to constitute a quorum. A quorum is required to transact business at the Annual Meeting.

Your shares will be counted toward the quorum only if you submit a valid proxy (or a valid proxy is submitted on your behalf by your broker, fiduciary or custodian) or if you attend the Annual Meeting virtually and vote. Abstentions and broker non-votes will be counted toward the quorum requirement. If there is no quorum, the chairman of the Annual Meeting or the holders of a majority of shares of common stock virtually present at the Annual Meeting, either personally or by proxy, may adjourn the Annual Meeting to another time or date.

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How Many Votes Are Required to Approve Each Proposal and How Are Votes Counted?

Votes will be counted by Borden Consulting Group, the Inspector of Elections appointed for the Annual Meeting.

Proposal 1: Election of Directors

A nominee will be elected as a director at the Annual Meeting if the nominee receives a plurality of the votes cast “FOR” his or her election. “Plurality” means that the individuals who receive the largest number of votes cast “FOR” are elected as directors. Broker non-votes and votes that are withheld will not be counted as votes cast on the matter and will have no effect on the outcome of the election. Stockholders do not have cumulative voting rights for the election of directors.

Proposal 2: Ratification of Independent Registered Public Accounting Firm

The majority of votes cast on the proposal is required for approval of Proposal 2. Abstentions and broker non-votes, if any, will not be counted as votes cast on the matter.

Who Is Paying for This Proxy Solicitation?

We will pay the costs associated with the solicitation of proxies, including the preparation, assembly, printing and mailing of the proxy materials, any solicitation by telephone or other electronic means, and any in-person solicitation. We may also reimburse brokers, fiduciaries or custodians for the cost of forwarding proxy materials to beneficial owners of shares of common stock held in “street name.”

Our employees, officers and directors may also solicit proxies, but we will not pay additional compensation for any of these services.

How Can I Find out the Voting Results?

We expect to announce preliminary voting results at the Annual Meeting. Final voting results will be published in a Current Report on Form 8-K to be filed with the SEC within four business days after the Annual Meeting.

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PROPOSAL 1: ELECTION OF DIRECTORS

In accordance with our Bylaws, the Board has fixed the number of directors constituting the Board at seven. At the Annual Meeting, the stockholders will vote to elect the two Class I director nominees named in this Proxy Statement to serve until the 2025 Annual Meeting of Stockholders or until their successors are duly elected and qualified or until their earlier resignation or removal. Our Board has nominated Dr. Karen Ferrante and Matthew E. Ros, each of whom is a current Class I director, for re-election to our Board.

Our director nominees have indicated that they are willing and able to serve as directors. However, if any of them becomes unable or, for good cause, unwilling to serve, proxies may be voted for the election of such other person as shall be designated by our Board, or the Board may decrease the size of the Board.

Information Regarding Director Nominees and Continuing Directors

Our Board is divided into three classes, with members of each class holding office for staggered three-year terms. There are currently two Class I directors, who are up for election for a term expiring at the 2025 Annual Meeting of Stockholders; three Class II directors, whose terms expire at the 2023 Annual Meeting of Stockholders; and two Class III directors, whose terms expire at the 2024 Annual Meeting of Stockholders.

Biographical and other information regarding our director nominees and directors continuing in office, including the primary skills and experiences considered by our Nominating and Corporate Governance Committee (the “Nominating Committee”) in determining to recommend them as nominees, is set forth below.

Class I Director Nominees

Karen Ferrante, M.D. Dr. Ferrante has served as a member of our Board since February 2018. Dr. Ferrante served as the Chief Medical Officer and Head of Research and Development of Tokai Pharmaceuticals, Inc (Nasdaq: TKAI), a biopharmaceutical company focused on developing treatments for prostate cancer and other hormonally driven diseases, from April 2014 until August 2016. From 2007 to July 2013, Dr. Ferrante held senior positions at Millennium Pharmaceuticals, Inc. and its parent company, Takeda Pharmaceutical Company Limited (NYSE: TAK), including Chief Medical Officer and subsequently, Oncology Therapeutic Area Head and Cambridge USA Site Head from May 2013 to July 2013. Dr. Ferrante previously held positions of increasing responsibility at Pfizer Global Research and Development and Bristol-Myers Squibb Company (NYSE: BMY). Dr. Ferrante serves on the board of directors of MacroGenics, Inc. (Nasdaq: MGNX) and HUTCHMED (China) Limited (Nasdaq: HCM). Dr. Ferrante also served as a director of Progenics Pharmaceuticals, Inc. from 2014 until its acquisition by Lantheus Holdings, Inc. (Nasdaq: LNTH) in 2020 and Baxalta Inc., a previously publicly-

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traded global biopharmaceutical company, from 2015 until its acquisition by Shire plc in 2016. She has also served as an advisory board member for Kazia Therapeutics Limited (Nasdaq: KZIA) since 2016 and Trillium Therapeutics Inc. (Nasdaq: TRIL) from 2020 until its acquisition by Pfizer in November 2021. Dr. Ferrante holds an M.D. from Georgetown University and a B.S. in Chemistry and Biology from Providence College.

We believe Dr. Ferrante is qualified to serve on our Board because of her extensive leadership, scientific, business and managerial experience in the biotechnology industry and her experience and expertise serving as a member of the board of directors of several biotechnology companies.

Matthew E. Ros. Mr. Ros has served as a member of our Board since July 2019. Mr. Ros has more than 30 years of experience in global pharmaceutical and early-stage biotechnology companies, building and leading teams across sales, marketing, franchise strategy and business operations. He was recently appointed as Chief Executive Officer of Fore Biotherapeutics Inc., a clinical-stage precision oncology company, in April 2022. Mr. Ros previously served as Chief Strategy and Business Officer of Epizyme, Inc. (Nasdaq: EPZM), a biopharmaceutical company, from September 2018 to October 2021. He served as Chief Operating Officer of Epizyme from May 2016 to September 2018. Prior to joining Epizyme, from September 2010 to May 2016, Mr. Ros served in increasing levels of responsibility at Sanofi S.A. (Nasdaq: SNY), a multinational pharmaceutical company, most recently as Chief Operating Officer/Global Head of the Oncology business unit from December 2014 to May 2016. Prior to that role, Mr. Ros served in the rare disease business of Genzyme Corporation, a Sanofi company, where he served as Vice President and Franchise Head of its Pompe disease unit from September 2012 to December 2014, and also served as the Associate Vice President and Iniparib Global Brand Leader in Sanofi’s Oncology business unit from September 2010 to September 2012. From October 2007 to June 2010, Mr. Ros served at ARIAD Pharmaceuticals, Inc., a global oncology company, most recently as Senior Vice President, Commercial Operations. He started his pharmaceutical career in Bristol-Myers Squibb’s Oncology Division, serving in roles with increasing responsibility from 1990 to 2007. He received a B.S. from the State University of New York, College at Plattsburgh and completed the Executive Education Program in Finance and Accounting for the Non-Financial Manager at Wharton School of the University of Pennsylvania.

We believe Mr. Ros is qualified to serve on our Board because of his extensive leadership, executive, managerial and business experience with life sciences companies.

Class II Directors Continuing in Office

Chris Cain, Ph.D. Dr. Cain has served as a member of our Board since July 2020 and is a designee of Fairmount Funds Management LLC (“Fairmount Funds”), a healthcare investment fund. Dr. Cain has served as Director of Research at Fairmount Funds since April 2020. From February 2019 to February 2020, Dr. Cain served as Vice President at Samsara BioCapital, a biotherapeutics-focused venture capital fund. Prior to that role, Dr. Cain worked at Apple Tree Partners, a life sciences-focused venture capital fund, from 2016 to January 2019, and at RA Capital Management, an investment management company, before that. Previously, Dr. Cain was a writer and editor at BioCentury Publications. He received a B.A. from the University of California, Santa Barbara and a Ph.D. in Biochemistry and Molecular Biology from the University of California, San Francisco.

We believe Dr. Cain is qualified to serve on our Board because of his extensive leadership, scientific, business and managerial experience in the biotechnology industry.

Arlene M. Morris. Ms. Morris has served as a member of our Board since July 2019. Ms. Morris has served as Chief Executive Officer of Willow Advisors, a consultancy advising biotech companies on financing, strategy and business development, since 2015. Previously, she spent over a decade leading public biotechnology companies. From 2012 to 2015, Ms. Morris served as Chief Executive Officer of Syndax Pharmaceuticals Inc. (Nasdaq: SNDX), a biopharmaceutical company focused on the development and commercialization of an epigenetic therapy for treatment-resistant cancers. Prior to this, she served as President and Chief Executive Officer of Affymax Inc. (OTCMKTS: AFFY), a biotechnology company, where she led the company through the

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development of peginesatide (Omontys^®). She spent 15 years at Johnson & Johnson (NYSE: JNJ), a pharmaceutical company, in marketing, sales and senior level business development positions. Ms. Morris served on the board of directors of Dimension Therapeutics, Inc. (Nasdaq: DMTX) from 2015 to 2018 and Neovacs, SA (Euronext: ALNEV) from 2011 to 2020. She was also a director of Biodel Inc., a publicly traded specialty pharmaceutical company, from 2015 until its merger with Albireo Limited in 2016. Ms. Morris is currently a member of the board of directors of Viveve Medical, Inc. (Nasdaq: VIVE), Palatin Technologies, Inc. (NYSE: PTN) and Viridian Therapeutics, Inc. (Nasdaq: VRDN). She received a B.A. in Biology and Chemistry from Carlow College.

We believe Ms. Morris is qualified to serve on our Board because of her extensive leadership, executive, managerial and board experience within pharmaceutical and biotechnology industries.

Todd Shegog. Mr. Shegog has served as a member of our Board since February 2021. Mr. Shegog has more than 25 years of financial, operations, corporate strategy and compliance expertise in the biotechnology and pharmaceutical industries. He has served as Senior Vice President and Chief Financial Officer of Forma Therapeutics, Inc. (Nasdaq: FMTX), a clinical-stage biopharmaceutical company, since September 2019. Prior to Forma Therapeutics, Mr. Shegog served as Chief Financial Officer of Synlogic, Inc. (Nasdaq: SYBX), a clinical-stage biopharmaceutical company, where he directed the company’s financial strategy and management as well as facilities and information systems from September 2016 to September 2019. From April 2014 to August 2016, Mr. Shegog served as Senior Vice President and Chief Financial Officer at Forum Pharmaceuticals, Inc., an early-stage biopharmaceutical company, where he was responsible for finance, operations and information systems during their pursuit of innovative therapies for schizophrenia and Alzheimer’s disease. He also served as the Chief Financial Officer of Millennium Pharmaceuticals, Inc., now Takeda Oncology, where he was responsible for management of the company’s financial resources, corporate planning, financial reporting and compliance from 1998 to 2014. Mr. Shegog earned a B.S. in Electrical Engineering from Lafayette College and an M.B.A. from the Tepper School of Management at Carnegie Mellon University.

We believe Mr. Shegog is qualified to serve on our Board because of his financial expertise, extensive leadership, executive, managerial and business experience with life sciences companies.

Class III Directors Continuing in Office

Andrew Robbins. Mr. Robbins has served as our Chief Executive Officer, President, principal executive officer and a member of our Board since October 2020. Prior to joining Cogent, Mr. Robbins served as Chief Operating Officer at Array BioPharma Inc., a pharmaceutical company, from March 2015 through its acquisition by Pfizer Inc. (NYSE: PFE), a pharmaceutical company, in July 2019, after serving as its Senior Vice President, Commercial Operations from July 2012 to March 2015. From January 2007 to July 2012, Mr. Robbins held management positions at Hospira, Inc., a pharmaceutical and medical device company, including General Manager and Vice President of the U.S. Alternate Site business unit and Vice President of Corporate Development. Prior to Hospira, Mr. Robbins held commercial and leadership positions within Pfizer’s oncology unit. Additionally, Mr. Robbins currently serves on the board of directors of Harpoon Therapeutics, Inc. (Nasdaq: HARP) and Turmeric Acquisition Corporation (Nasdaq: TMPMU). Mr. Robbins holds an M.B.A. from the Kellogg School of Management, Northwestern University and a bachelor’s degree from Swarthmore College.

We believe Mr. Robbins is qualified to serve on our Board because of his extensive commercial, development and strategic leadership experience in the pharmaceutical industry.

Peter Harwin. Mr. Harwin has served as a member of our Board since July 2020 and is a designee of Fairmount Funds. He is currently a managing member at Fairmount Funds, a healthcare investment fund he co-founded in April 2016. Prior to Fairmount Funds, Mr. Harwin served as a member of the investment team at Boxer Capital, LLC, part of the Tavistock Group, based in San Diego. Mr. Harwin also serves on the board of directors of Viridian Therapeutics, Inc. (Nasdaq: VRDN) and Paragon Therapeutics, Inc. Mr. Harwin received his B.B.A. from Emory University.

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We believe Mr. Harwin is qualified to serve on our Board because of his extensive leadership, executive, managerial and board experience within pharmaceutical and biotechnology industries.

Board Recommendation

The Board recommends a vote “FOR” the election of each of the Class I director nominees set forth above.

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PROPOSAL 2: RATIFICATION OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Our Audit Committee has selected PricewaterhouseCoopers LLP (“PwC”) as the Company’s independent registered public accounting firm for the year ending December 31, 2022. In this Proposal 2, we are asking stockholders to vote to ratify this selection. Representatives of PwC are expected to be present at the Annual Meeting. They will have the opportunity to make a statement, if they desire to do so, and will be available to respond to appropriate questions from stockholders.

Stockholder ratification of the selection of PwC as the Company’s independent auditor is not required by law or our bylaws. However, we are seeking stockholder ratification as a matter of good corporate practice. If our stockholders fail to ratify the selection, the committee will reconsider its selection. Even if the selection is ratified, the committee, in its discretion, may direct the selection of a different independent auditor at any time during the year if it determines that such a change would be in the best interests of the Company and our stockholders.

PwC has served as our independent auditor since 2015. The following table summarizes the audit fees billed and expected to be billed by PwC for the indicated fiscal years and the fees billed by PwC for all other services rendered during the indicated fiscal years. All services associated with such fees were pre-approved by our Audit Committee in accordance with the “Pre-Approval Policies and Procedures” described below.

Pre-Approval Policies and Procedures

Our Audit Committee has adopted policies and procedures relating to the approval of all audit and non-audit services performed by our independent auditor in order to ensure that these services do not impair the auditor’s independence. In accordance with these policies and procedures, we will not engage our independent auditor to render audit or non-audit services unless the service is specifically approved in advance by our Audit Committee or the engagement is entered into pursuant to the pre-approval procedure described below. The Audit Committee does not delegate its responsibility to approve services performed by the independent registered public accounting firm to any member of management.

From time to time, our Audit Committee may pre-approve specified types of services that are expected to be provided to us by our independent auditor during the next 12 months. Any such pre-approval details the particular service or type of services to be provided and is also generally subject to a maximum dollar amount.

Report of the Audit Committee

The Audit Committee has reviewed and discussed the audited financial statements for the year ended December 31, 2021 with the Company’s management and with PwC, the Company’s independent registered

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public accounting firm. The Audit Committee has discussed with PwC the matters required to be discussed by the applicable standards of the Public Company Accounting Oversight Board (“PCAOB”) and the SEC. The Audit Committee has also received the written disclosures and the letter from PwC pursuant to applicable PCAOB requirements regarding its communications with the Audit Committee concerning independence, and the Audit Committee has discussed with PwC its independence. Based on the foregoing, the Audit Committee recommended to the Board that the audited consolidated financial statements be included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 for filing with the SEC.

This report is provided by the following directors, who serve on the Audit Committee:

Todd Shegog (Chair)

Peter Harwin

Arlene M. Morris

Matthew E. Ros

Board Recommendation

The Board recommends a vote “FOR” the ratification of the selection of PwC to serve as our independent registered public accounting firm.

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CORPORATE GOVERNANCE

Our business affairs are managed under the direction of our Board. Our Board has adopted a set of Corporate Governance Guidelines as a framework for the governance of the Company, which is posted on our website located at https://investors.cogentbio.com/, under “Corporate Governance.”

Board Composition

Director Nomination Process

The Nominating Committee is responsible for, among other things, overseeing succession planning for directors and building a qualified board to oversee management’s execution of the Company’s strategy and safeguard the long-term interests of stockholders. In this regard, the committee is charged with developing and recommending Board membership criteria to the Board for approval, evaluating the composition of the Board annually to assess the skills and experience that are currently represented on the Board and the skills and experience that the Board may find valuable in the future, and identifying, evaluating and recommending potential director candidates.

In identifying potential candidates for Board membership, the Nominating Committee considers recommendations from directors, stockholders, management and others, including, from time to time, third-party search firms to assist it in locating qualified candidates. The committee does not distinguish between nominees recommended by stockholders and other nominee recommendations. Once potential director candidates are identified, the committee, with the assistance of management, undertakes a vetting process that considers each candidate’s background, independence and fit with the Board’s priorities. As part of this vetting process, the committee, as well as other members of the Board and the CEO, may conduct interviews with the candidates. If the committee determines that a potential candidate meets the needs of the Board and has the desired qualifications, it recommends the candidate to the full Board for appointment or nomination and to the stockholders for election at the annual meeting.

Criteria for Board Membership

In assessing potential candidates for Board membership and in assessing Board composition, the Nominating Committee considers a wide range of factors, including directors’ experience, knowledge, integrity, understanding of our business environment and specific skills they may possess that are helpful to the Company (including leadership experience, financial expertise and industry knowledge). The committee generally believes that it is important for all Board members to possess the following qualifications:

The Nominating Committee seeks to balance the experience, skills and characteristics represented on the Board and does not assign specific weight to any of these factors.

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Board Diversity

In addition to the factors discussed above, the Board and the Nominating Committee actively seek to achieve a diversity of occupational and personal backgrounds on the Board. The Nominating Committee considers a potential director candidate’s ability to contribute to the diversity of personal backgrounds on the Board, including with respect to gender, race, ethnic and national background, geography, age and sexual orientation. The Nominating Committee assesses its effectiveness in balancing these considerations in connection with its annual evaluation of the composition of the Board. In this regard, our current Board of 7 directors includes 2 directors who self-identify as female (28%).

In accordance with Nasdaq’s recently adopted board diversity listing standards, we are disclosing aggregated statistical information about our Board’s self-identified gender and racial characteristics and LGBTQ+ status as voluntarily confirmed to us by each of our directors.

Stockholder Recommendations for Directors

It is the Nominating Committee’s policy to consider written recommendations from stockholders for nominees for director. The committee considers nominees recommended by our stockholders in the same manner as a nominee recommended by our Board members or management. Any such recommendations should be submitted to the committee as described in the section titled “Stockholder Communications” below and should include the following information: (i) the name, age, business address and residence address of the nominee; (ii) the principal occupation or employment of the nominee; (iii) the class and number of shares of the Company that are held of record or are beneficially owned by the nominee and any derivative positions held or beneficially held by the nominee; (iv) whether and the extent to which any hedging or other transaction or series of transactions has been entered into by or on behalf of the nominee with respect to any securities of the Company, and a description of any other agreement, arrangement or understanding (including any short position or any borrowing or lending of shares), the effect or intent of which is to mitigate loss to, or to manage the risk or benefit of share price changes for, or to increase or decrease the voting power of the nominee; (v) a description of all arrangements or understandings between or among the stockholder and each nominee and any other person or persons (naming such person or persons) pursuant to which the nominations are to be made by the stockholder or concerning the nominee’s potential service on the Board; (vi) a written statement executed by the nominee acknowledging that as a director of the Company, the nominee will owe fiduciary duties under Delaware law with respect to the Company and its stockholders and (vii) all information relating to such person that is required to be disclosed in solicitations of proxies for election of directors in an election contest, or is otherwise required, in each case pursuant to Regulation 14A under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) (including such person’s written consent to being named in the proxy statement as a nominee and to serving as a director if elected).

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Board Leadership Structure

Mr. Harwin serves as our independent Chairman while Mr. Robbins serves as our President and Chief Executive Officer. Our Corporate Governance Guidelines provide our Board with the flexibility to combine or separate the positions of Chairman and CEO. Currently, the Board believes that the roles of Chairman and CEO should be separate and that the Chairman should be an independent director as this structure enables our independent Chairman to oversee corporate governance matters and our CEO to focus on leading the Company’s business.

The independent directors have the opportunity to meet in executive session without management present at every regular Board meeting and at such other times as may be determined by the Chairman. The purpose of these executive sessions is to encourage and enhance communication among independent directors.

The Board believes that its programs for overseeing risk, as described in the “Board Risk Oversight” section below, would be effective under a variety of leadership frameworks. Accordingly, the Board’s risk oversight function did not significantly impact its selection of the current leadership structure.

Director Independence

Nasdaq listing rules require a majority of a listed company’s board of directors to be comprised of independent directors who, in the opinion of the board of directors, do not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. Subject to specified exceptions, each member of a listed company’s audit, compensation and nominating committees must be independent, and audit and compensation committee members must satisfy additional independence criteria under the Exchange Act.

Our Board undertook a review of its composition and the independence of each director. Based upon information requested from and provided by each director concerning his or her background, employment and affiliations, our Board has determined that each of our current directors listed above under “Information Regarding Director Nominees and Continuing Directors,” with the exception of Andrew Robbins, is an “independent director” as defined under the Nasdaq listing rules. Mr. Robbins is not an independent director because he is our Chief Executive Officer. In making such determinations, our Board considered the relationships that each such non-employee director has with our Company and all other facts and circumstances our Board deemed relevant in determining independence, including the beneficial ownership of our capital stock by each non-employee director. Our Board also determined that each of the directors currently serving on the Audit Committee and the Compensation Committee satisfy the additional independence criteria under the Exchange Act.

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Board Committees

Our Board has a separately designated Audit Committee, Compensation Committee and Nominating Committee, each of which is comprised solely of independent directors with the membership and responsibilities described below. Members serve on these committees until their resignation or until otherwise determined by our Board. Each of these committees is empowered to retain outside advisors as it deems appropriate, regularly reports its activities to the full Board and has a written charter which is posted on our website located at https://investors.cogentbio.com/, under “Corporate Governance.”

Audit Committee. The primary responsibilities of our Audit Committee are to oversee the accounting and financial reporting processes of the Company and its subsidiaries, including the audits of the Company’s financial statements, the integrity of the financial statements and the annual review of the performance, effectiveness and independence of the outside auditor. This includes reviewing the financial information provided to stockholders and others and the adequacy and effectiveness of the Company’s internal controls. The committee also makes recommendations to the Board as to whether financial statements should be included in the Company’s Annual Report on Form 10-K.

Mr. Shegog qualifies as an “audit committee financial expert,” as that term is defined in the rules and regulations established by the SEC, and all members of the Audit Committee are “financially literate” under Nasdaq listing rules.

Compensation Committee. The primary responsibilities of our Compensation Committee are to periodically review and approve the compensation and other benefits for our senior officers and directors. This includes reviewing and approving corporate goals and objectives relevant to the compensation of our senior officers, evaluating the performance of these officers in light of the goals and objectives, and setting the officers’ compensation based on those evaluations. The committee also administers and makes recommendations to the Board regarding equity incentive plans that are subject to the Board’s approval and approves the grant of equity awards under the plans. For compensation matters and equity grants to our CEO and Board members, the committee makes recommendations to the Board, and the Board is responsible for reviewing and approving all such matters.

The Compensation Committee may delegate its authority to one or more subcommittees or to one member of the committee. The committee may also delegate authority to review and approve the compensation of our employees to certain of our executive officers. Even where the committee does not delegate authority, our executive officers will typically make recommendations to the committee regarding compensation to be paid to our employees and the size of equity awards under our equity incentive plans, but will not be present during voting or deliberations on their own compensation. The committee has the authority to engage independent advisors, such as compensation consultants, to assist it in carrying out its responsibilities. The committee engaged Radford, an AON company, in 2021 to provide advice regarding the amount and form of executive and director compensation.

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Nominating Committee. The primary responsibilities of our Nominating Committee are to engage in succession planning for the Board, develop and recommend to the Board criteria for identifying and evaluating qualified director candidates, and make recommendations to the Board regarding candidates for election or reelection to the Board at each annual stockholders’ meeting. In addition, the committee is responsible for overseeing our corporate governance practices and making recommendations to the Board concerning corporate governance matters. The committee is also responsible for making recommendations to the Board concerning the structure, composition and functioning of the Board and its committees.

Board Risk Oversight

We believe that risk management is an important part of establishing and executing on the Company’s business strategy. Our Board, as a whole and at the committee level, focuses its oversight on the most significant risks facing the Company and on its processes to identify, prioritize, assess, manage and mitigate those risks. The committees oversee specific risks within their purview, as follows:

Our Board and its committees receive regular reports from members of the Company’s senior management on areas of material risk to the Company, including strategic, operational, financial, legal and regulatory risks. While our Board has an oversight role, management is principally tasked with direct responsibility for management and assessment of risks and the implementation of processes and controls to mitigate their effects on the Company.

Other Corporate Governance Practices and Policies

Director Attendance

During the year ended December 31, 2021, the Board met seven times and acted by unanimous written consent two times. During 2021, each current member of the Board attended at least 75% of the aggregate number of meetings of the Board and the committees on which he or she served during the period in which he or she was on the Board or committee. Directors are encouraged to attend the annual meeting of stockholders. All of our directors then serving on the Board attended the 2021 Annual Meeting of Stockholders.

Stockholder Communications

Stockholders and other interested parties may communicate with our Board or a particular director by sending a letter addressed to the Board or a particular director to our Corporate Secretary at the address set forth on the first page of this Proxy Statement. These communications will be compiled and reviewed by our Corporate Secretary, who will determine whether the communication is appropriate for presentation to the Board or the particular director. The purpose of this screening is to allow the Board to avoid having to consider irrelevant or inappropriate communications (such as advertisements, solicitations and hostile communications).

To enable the Company to speak with a single voice, as a general matter, senior management serves as the primary spokesperson for the Company and is responsible for communicating with various constituencies, including stockholders, on behalf of the Company. Directors may participate in discussions with stockholders and other constituencies on issues where Board-level involvement is appropriate. In addition, the Board is kept informed by senior management of the Company’s stockholder engagement efforts.

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Code of Business Conduct and Ethics

Our Board has adopted a written code of business conduct and ethics that applies to our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. A current copy of the code is available on our website located at https://investors.cogentbio.com/, under “Corporate Governance.” We intend to disclose any amendments to the code, or any waivers of its requirements, on our website to the extent required by applicable rules.

Anti-Hedging Policy

Certain transactions in our securities (such as purchases and sales of publicly traded put and call options, and short sales) create a heightened compliance risk or could create the appearance of misalignment between management and stockholders. In addition, securities held in a margin account or pledged as collateral may be sold without consent if the owner fails to meet a margin call or defaults on the loan, thus creating the risk that a sale may occur at a time when an officer or director is aware of material, non-public information or otherwise is not permitted to trade in Company securities. Our insider trading policy expressly prohibits short sales of our stock by our executive officers, directors, employees and certain designated consultants and contractors. Our insider trading policy also expressly prohibits, without the advance approval of our audit committee, purchases or sales of puts, calls or other derivative securities of the Company or any derivative securities or any hedging transactions that provide the economic equivalent of ownership.

Director Compensation

Outside Director Compensation Policy

We adopted a policy for compensating our non-employee directors with a cash retainer for service on the Board and for service on each committee on which the director is a member. The chairman of each committee receives a higher retainer for such service. These fees are payable in arrears in four equal quarterly installments on the last day of each quarter, provided that the amount of such payment is prorated for any portion of such quarter that the director is not serving on our Board. The Compensation Committee periodically reviews compensation paid to our non-employee directors, considering input from the Compensation Committee’s independent compensation consultant, and makes recommendations for adjustments, as appropriate, to the full Board. The Board approved changes to the outside director compensation policy as reflected below, in order to provide compensation levels for our non-employee directors that are more in line with our peer companies. The fees payable to non-employee directors for service on the Board and for service on each committee of the Board on which the director is a member are as follows:

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We also reimburse our non-employee directors for reasonable travel and out-of-pocket expenses incurred in connection with attending our Board and committee meetings.

Pursuant to our director compensation policy, directors are given the opportunity to elect to receive all or a portion of their retainer and committee fees in the form of an equity award of (a) unrestricted shares having a grant date fair value equal to the amount (or portion thereof) of such retainer and committee fees or (b) fully vested stock options to purchase common stock based on the Black-Scholes option-pricing model as of the date of grant. Any such election must be made (i) for any continuing non-employee director, before the start of the calendar year with respect to any cash compensation for such calendar year and (ii) for any new non-employee director, within 30 days of her or his election to the Board. Any such stock options are fully vested upon grant and expire ten years from the date of grant.

In addition, our director compensation policy provides that each new non-employee director elected to our Board receives an initial, one-time stock option grant to purchase 37,500 (increased to 61,400 beginning in 2022) shares of our common stock (the “Initial Award”), which vests in equal monthly installments over three years, subject to continued service as a member of the Board. In addition, each continuing non-employee member of the Board, other than a director receiving an Initial Award, receives, at the time of the Company’s annual meeting, an annual equity grant of options to purchase 18,750 (increased to 30,700 beginning in 2022) shares of our common stock, which vests in full upon the earlier of the first anniversary of the date of grant or the date of the next annual meeting of the Company’s stockholders, subject to continued service as a member of the Board through such date. Notwithstanding the foregoing, in 2021 only, in lieu of the typical annual grants, each non-employee director received a stock option grant to purchase 60,000 shares in March prior to the 2021 annual meeting, and a portion of each grant was contingent on stockholder approval of our equity plan. These stock options vest in equal monthly installments over three years. This one-time change in our regular annual grant practice was made in order to provide grants following our stock split that would incentivize our directors over a three-year period and compensate them on a level commensurate with our peers. This program is intended to provide a total compensation package that enables us to attract and retain qualified and experienced individuals to serve as directors and to align our directors’ interests with those of our stockholders.

Fiscal Year 2021 Director Compensation Table

The table below shows all compensation paid to or earned in 2021 by our non-employee directors. Executives who serve as directors do not receive any compensation for service as a director. The compensation received by Mr. Robbins for his service to us during 2021 as our Chief Executive Officer is presented in the 2021 Summary Compensation Table in “Executive Compensation” below.

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Compensation Committee Interlocks and Insider Participation

None of the members of our Compensation Committee has at any time during the prior three years been one of our officers or employees. None of our executive officers currently serves, or in the past fiscal year has served, as a member of the board or compensation committee of any entity that has one or more executive officers serving on our Board or Compensation Committee.

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EXECUTIVE OFFICERS

Biographical and other information regarding our executive officers is set forth below. There are no family relationships among any of our directors or executive officers.

John Green. Mr. Green has served as our Chief Financial Officer, principal accounting officer and principal financial officer since July 2020. Prior to his promotion, Mr. Green was our Vice President of Finance and Controller from April 2018 to June 2020. Mr. Green brings nearly 20 years of strategic finance and accounting experience to his position, nearly half of which has been in the biotechnology industry for both public and private companies. Prior to joining Cogent, Mr. Green served as Principal Accounting Officer at Merrimack Pharmaceuticals, Inc. (Nasdaq: MACK), a biopharmaceutical company, from March 2017 to June 2018. From November 2015 to March 2017, he served as the Controller at Fractyl Laboratories, Inc., a medical technology company. From June 2014 to November 2015, Mr. Green served as Director of Accounting at Dicerna Pharmaceuticals, Inc. (Nasdaq: DRNA), a biopharmaceutical company. Mr. Green is a Chartered Professional Accountant and holds a B.S. in Chemistry and Biology from Acadia University.

Evan Kearns. Mr. Kearns has served as our Chief Legal Officer and Corporate Secretary since May 2021, where he is responsible for the Company’s legal and compliance functions. Prior to joining the Company, Mr. Kearns served as Vice President, General Counsel, Corporate Secretary and Chief Compliance Officer at Agenus Inc. (Nasdaq: AGEN), a biotechnology company, from July 2018 to April 2021, where he advised on corporate and securities law matters, as well as M&A, financing and licensing transactions. From December 2017 to July 2018, he served as Vice President, Associate General Counsel at Agenus in a similar capacity. Before joining Agenus, he served as a life sciences corporate associate with Goodwin Proctor LLP, a law firm in Boston. Mr. Kearns received his J.D. from the University of Toledo College of Law and his B.A. in Economics from Colby College.

John Robinson, Ph.D. Dr. Robinson has served as our Chief Scientific Officer since April 2021. He has over 20 years of small molecule drug discovery experience. Prior to joining the Company, Dr. Robinson served as Vice President of Medicinal Chemistry at Pfizer Boulder Research and Development, a drug discovery and development center, from July 2019 to March 2021. From December 2002 to July 2019, he served in a variety of scientific and leadership positions at Array BioPharma Inc., a biopharmaceutical company, including most recently, as Executive Director and Head of Chemistry. Dr. Robinson received his B.S. in Biochemistry from Indiana University of Pennsylvania and his Ph.D. in Synthetic Organic Chemistry from the University of Delaware.

Jessica Sachs, M.D. Dr. Sachs has served as our Chief Medical Officer since June 2019. Prior to assuming this role, she served as our Vice President of Clinical Sciences from April 2017 to June 2019, and she was responsible for the clinical development strategy and medical and translational oversight of the Cogent portfolio. Dr. Sachs has over 16 years of experience in oncology and pediatrics. From 2012 to April 2017, Dr. Sachs served as Senior Medical Director of Clinical Research at Takeda Pharmaceutical Company Limited (NYSE: TAK), a global biopharmaceutical company, where she led multiple clinical programs in oncology and transplantation.

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From 2010 to 2012, Dr. Sachs was Associate Director at Genzyme Corporation, a biotechnology company, where she was responsible for post-marketing safety surveillance and risk management activities for a variety of oncology products. Dr. Sachs has been a faculty member of the Harvard Medical School since 2007 and is an Assistant in Pediatrics in the Division of Pediatric Hematology/Oncology at the Massachusetts General Hospital. She completed her fellowship in pediatric hematology and oncology at the Dana Farber Cancer Institute and Children’s Hospital Boston. She received her M.D. from Washington University in St. Louis and her B.S. from Duke University.

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EXECUTIVE COMPENSATION

Our named executive officers (“NEOs”) for 2021, which consist of our principal executive officer and the next two most highly compensated executive officers, are:

2021 Summary Compensation Table

The following table summarizes the compensation awarded to, earned by or paid to our NEOs for 2021 and 2020.

Narrative to Summary Compensation Table

Our Board and Compensation Committee review compensation annually for all employees, including our executives. In setting executive base salaries and bonuses and granting equity incentive awards, they consider compensation for comparable positions in the market, the historical compensation levels of our executives, individual performance as compared to our expectations and objectives, our desire to motivate our employees to achieve short-and long-term results that are in the best interests of our stockholders and our desire to incentivize a long-term commitment to our Company. We target a general competitive position, based on independent third-party benchmark analytics to inform the mix of compensation of base salary, bonus and long-term incentives.

Our Compensation Committee has historically reviewed our executives’ compensation and made recommendations to the Board for approval of any changes. In 2021, our Compensation Committee assumed responsibility for approving all executive compensation matters other than for our CEO, which must still be recommended to the Board for approval. Our Compensation Committee typically reviews and discusses management’s proposed compensation with the CEO for all executives other than the CEO. Based on those discussions and its discretion, taking into account the factors noted above, the Compensation Committee then determines the compensation for each executive officer other than the CEO. In 2021, the Compensation

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Committee retained the services of Radford, an AON company, as its external compensation consultant and the Board and the Compensation Committee considered Radford’s input on certain compensation matters as they deemed appropriate. Our Compensation Committee has assessed the independence of Radford consistent with Nasdaq listing standards and has concluded that the engagement of Radford does not raise any conflict of interest.

Annual Base Salary

Each named executive officer’s base salary is a fixed component of annual compensation for performing specific duties and functions, and has been established by our Board taking into account each individual’s role, responsibilities, skills and experience. Base salaries for our named executive officers are reviewed annually by our Compensation Committee, typically in connection with our annual performance review process, and adjusted from time to time, based on the recommendation of the Compensation Committee, to realign salaries with market levels after taking into account individual responsibilities, performance and experiences.

Cash Bonus

From time to time, our Board or Compensation Committee may approve annual bonuses for our named executive officers based on individual performance, Company performance or as otherwise determined appropriate. Cash bonuses for the 2021 performance year were funded at 100% of target based on achievement of nearly all corporate goals, as well as other key accomplishments during the course of the year, particularly in relation to the research team and research pipeline.

Long-Term Equity Incentives

Our equity grant program is intended to align the interests of our named executive officers with those of our stockholders and to motivate them to make important contributions to our performance. During the year ended December 31, 2021, we made grants of stock options to each of our named executive officers. The grant date fair values of such awards are set forth in the “2021 Summary Compensation Table” above and the number of shares underlying such awards and the vesting terms of such awards are set forth in the “Outstanding Equity Awards at 2021 Fiscal Year End Table” below.

Outstanding Equity Awards at 2021 Fiscal Year End Table

The following table sets forth information regarding outstanding equity awards at the end of 2021 for each of our NEOs.

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Employment Arrangements with our Named Executive Officers

We have entered into employment agreements with each of our named executive officers. Each of our named executive officers is employed at will.

Andrew Robbins. Mr. Robbins’s employment agreement provides for “at will” employment. Pursuant to the terms of his employment agreement, Mr. Robbins is entitled to an annual base salary, which was set at $595,000 for 2021. Mr. Robbins is also eligible for annual incentive compensation targeted at 60% of his base salary. Mr. Robbins is eligible to participate in the employee benefit plans generally available to full-time employees, subject to the terms of those plans. Pursuant to the terms of his employment agreement, if Mr. Robbins’s employment is terminated by the Company without cause (as defined in his employment agreement) or by Mr. Robbins for good reason (as defined in his employment agreement), Mr. Robbins will receive any base salary through the date of termination, unpaid expense reimbursements, unused vacation accrued through the date of termination and any vested benefits under any employee benefit plan through the date of termination. Additionally, subject to Mr. Robbins’s execution of a release of potential claims against the Company, Mr. Robbins will be entitled to receive: (i) a lump sum in cash in an amount equal to 12 months of base salary, (ii) a monthly cash payment for 12 months for medical and dental benefits or Mr. Robbins’s COBRA health continuation period, whichever ends earlier, (iii) a lump sum in cash in an amount equal to 100% of Mr. Robbins’s target bonus for the then-current year and (iv) acceleration of vesting on any time-based options in which Mr. Robbins would have vested if he had remained employed for an additional 12 months. However, in the event that Mr. Robbins’s employment is terminated by the Company without cause, or Mr. Robbins terminates his employment with the Company for good reason, in either case for a period of 90 days prior to or 12 months following the occurrence of a change in control (as defined in his employment agreement), in lieu of the severance payments and benefits described in the preceding sentence and subject to Mr. Robbins’s execution of a release of potential claims against the Company, Mr. Robbins will be entitled to receive: (i) a lump sum in cash in an amount equal to 18 months of base salary, (ii) a lump sum in cash in an amount equal to 150% of Mr. Robbins’s target bonus for the then-current year, (iii) a monthly cash payment for 18 months for medical and dental benefits or Mr. Robbins’s COBRA health continuation period, whichever ends earlier and (iv) acceleration of vesting on any options.

Jessica Sachs, M.D. Jessica Sachs’s employment agreement provides for “at will” employment. Pursuant to the terms of her employment agreement, Dr. Sachs is entitled to an annual base salary, which was set at $460,000 for 2021. Dr. Sachs is also eligible for annual incentive compensation targeted at 40% of her base salary. Dr. Sachs is eligible to participate in the employee benefit plans generally available to full-time employees, subject to the terms of those plans. Pursuant to the terms of her employment agreement, if Dr. Sachs’s employment is terminated by us without cause (as defined in her employment agreement) or by Dr. Sachs for good reason (as defined in her employment agreement), Dr. Sachs will receive any base salary through the date of termination, unpaid expense reimbursements, unused vacation accrued through the date of termination and any vested benefits under any employee benefit plan through the date of termination. Additionally, subject to Dr. Sachs’s execution of a release of potential claims against us, Dr. Sachs will be entitled to receive: (i) a lump sum in cash in an amount equal to 12 months of base salary, (ii) a monthly cash payment for nine months for medical and dental benefits or Dr. Sachs’s COBRA health continuation period, whichever ends earlier, (iii) a lump sum in cash in an amount equal to Dr. Sachs’ target bonus for the then-current year pro-rated based on the portion of the year that Dr. Sachs was employed, and (iv) acceleration of vesting on any time-based equity awards in which Dr. Sachs would have vested if she had remained employed for an additional nine months. However, in the event that Dr. Sachs’s employment is terminated by us without cause, or Dr. Sachs terminates her employment with us for good reason, in either case within 12 months following the occurrence of a change in control (as defined in her employment agreement), in lieu of the severance payments and benefits described in the preceding sentence and subject to Dr. Sachs’s execution of a release of potential claims against us, Dr. Sachs

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will be entitled to receive: (i) a lump sum in cash in an amount equal to 12 months of base salary, (ii) a lump sum in cash in an amount equal to 100% of Dr. Sachs’s target bonus for the then-current year, (iii) a monthly cash payment for 12 months for medical and dental benefits or Dr. Sachs’s COBRA health continuation period, whichever ends earlier and (iv) acceleration of vesting on all equity awards.

John Robinson, Ph.D. John Robinson’s employment agreement provides for “at will” employment. Pursuant to the terms of his employment agreement, Dr. Robinson is entitled to an annual base salary, which was set at $425,000 for 2021. Dr. Robinson is also eligible for annual incentive compensation targeted at 40% of his base salary. Dr. Robinson is eligible to participate in the employee benefit plans generally available to full-time employees, subject to the terms of those plans. Pursuant to the terms of his employment agreement, if Dr. Robinson’s employment is terminated by us without cause (as defined in his employment agreement) or by Dr. Robinson for good reason (as defined in his employment agreement), Dr. Robinson will receive any base salary through the date of termination, unpaid expense reimbursements, unused vacation accrued through the date of termination and any vested benefits under any employee benefit plan through the date of termination. Additionally, subject to Dr. Robinson’s execution of a release of potential claims against us, Dr. Robinson will be entitled to receive: (i) a lump sum in cash in an amount equal to 12 months of base salary, (ii) a monthly cash payment for nine months for medical and dental benefits or Dr. Robinson’s COBRA health continuation period, whichever ends earlier, (iii) a lump sum in cash in an amount equal to Dr. Robinson’s target bonus for the then-current year pro-rated based on the portion of the year that Dr. Robinson was employed, and (iv) acceleration of vesting on any time-based equity awards in which Dr. Robinson would have vested if he had remained employed for an additional nine months. However, in the event that Dr. Robinson’s employment is terminated by us without cause, or Dr. Robinson terminates his employment with us for good reason, in either case within 12 months following the occurrence of a change in control (as defined in his employment agreement), in lieu of the severance payments and benefits described in the preceding sentence and subject to Dr. Robinson’s execution of a release of potential claims against us, Dr. Robinson will be entitled to receive: (i) a lump sum in cash in an amount equal to 12 months of base salary, (ii) a lump sum in cash in an amount equal to 100% of Dr. Robinson’s target bonus for the then-current year, (iii) a monthly cash payment for 12 months for medical and dental benefits or Dr. Robinson’s COBRA health continuation period, whichever ends earlier and (iv) acceleration of vesting on all equity awards.

Additional Narrative Disclosure

401(k) Plan

We maintain the Cogent Biosciences, Inc. 401(k) Plan, a tax-qualified retirement plan for our employees. The 401(k) Plan is intended to qualify under Section 401(k) of the Internal Revenue Service Code of 1986, as amended, so that contributions to the 401(k) Plan by employees or by us, and the investment earnings thereon, are not taxable to the employees until withdrawn from the 401(k) Plan, and so that contributions by us, if any, will be deductible by us when made. Under the 401(k) Plan, employees may elect to reduce their current compensation by up to the statutorily prescribed annual limit and to have the amount of such reduction contributed to the 401(k) Plan. We currently match 100% of an employee’s contributions to the 401(k) Plan up to 4% of an employee’s compensation.

Health and Welfare Benefits

All of our full-time employees, including our executive officers, are eligible to participate in certain medical, disability and life insurance benefit programs offered by us. We pay the premiums for term life insurance and long-term disability for all of our employees, including our executive officers. We also provide all employees, including executive officers, with a flexible spending account plan, an employee stock purchase plan and paid time off benefits, including vacation, sick time and holidays. We do not sponsor any qualified or non-qualified defined benefit plans for any of our employees or executives.

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Other Retirement Benefits

We do not maintain any defined benefit pension plans. In 2021, we adopted a nonqualified deferred compensation plan pursuant to which eligible participants, including our executive officers, may elect to defer a portion of their eligible compensation. None of the NEOs participated in the plan during 2021.

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CERTAIN INFORMATION ABOUT OUR COMMON STOCK

Security Ownership of Certain Beneficial Owners and Management

The following table presents information regarding beneficial ownership of our common stock as of March 1, 2022 by:

Beneficial ownership is determined in accordance with the rules of the SEC. Under such rules, beneficial ownership includes any shares of common stock over which the individual or entity has sole or shared voting power or investment power as well as any shares of common stock that the individual or entity has the right to acquire within 60 days after March 1, 2022. To our knowledge and subject to applicable community property rules, and except as otherwise indicated below, the persons and entities named in the table have sole voting and sole investment power with respect to all shares beneficially owned.

The percentage ownership information shown in the column titled “Percentage of Shares Beneficially Owned” in the table below is based on 45,813,667 shares of our common stock outstanding as of March 1, 2022 (plus, as to any particular beneficial owner, any shares as to which such person has the right to acquire beneficial ownership within 60 days thereafter). Unless otherwise indicated, the address of each beneficial owner listed in this table is the Company’s address set forth on the first page of this Proxy Statement.

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Delinquent Section 16(a) Reports

Section 16(a) of the Exchange Act requires our directors, officers and persons who beneficially own more than 10% of a registered class of our equity securities to file with the SEC initial reports of ownership and reports of changes in ownership of our common stock and other equity securities. To our knowledge, based solely on our review of Forms 3, 4 and 5 filed with the SEC or written representations that no Form 5 was required, during the year ended December 31, 2021 we believe that our directors, officers and persons who beneficially own more than 10% of a registered class of our equity securities timely filed all reports required under Section 16(a) of the Exchange Act, except that, due to administrative error, one Form 3 was filed late with respect to John Robinson, Ph.D.

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Securities Authorized for Issuance Under Equity Compensation Plans

The following table provides information as of December 31, 2021 with respect to the shares of our common stock that may be issued under our existing equity compensation plans.

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CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS

The following is a summary of each transaction or series of similar transactions since January 1, 2020, or any currently proposed transaction, to which we were or are a party in which:

Beneficial ownership of securities is determined in accordance with the rules of the SEC and generally includes voting or investment power with respect to such securities.

Related Party Transactions

Limitation of Liability

Our certificate of incorporation contains provisions that limit the liability of our directors for monetary damages to the fullest extent permitted by Delaware law. Consequently, our directors will not be personally liable to us or our stockholders for monetary damages for any breach of fiduciary duties as directors, except in certain circumstances. Any amendment to, or repeal of, these provisions will not eliminate or reduce the effect of these provisions in respect of any act, omission or claim that occurred or arose prior to that amendment or repeal. If the Delaware General Corporation Law is amended to provide for further limitations on the personal liability of directors of corporations, then the personal liability of our directors will be further limited to the greatest extent permitted by the Delaware General Corporation Law.

Indemnification

Our bylaws provide that we will indemnify, to the fullest extent permitted by law, any person who is or was a party or is threatened to be made a party to any action, suit or proceeding by reason of the fact that he or she is or was one of our directors or officers or is or was serving at our request as a director or officer of another corporation, partnership, joint venture, trust or other enterprise. Our bylaws provide that we may indemnify to the fullest extent permitted by law any person who is or was a party or is threatened to be made a party to any action, suit or proceeding by reason of the fact that he or she is or was one of our employees or agents or is or was serving at our request as an employee or agent of another corporation, partnership, joint venture, trust or other enterprise. Our bylaws also provide that we must advance expenses incurred by or on behalf of a director or officer in advance of the final disposition of any action or proceeding, subject to very limited exceptions. In addition, we have entered into and in the future plan to enter into agreements to indemnify our directors and executive officers. These agreements, among other things, require us to indemnify these individuals for certain expenses (including attorneys’ fees), judgments, fines and settlement amounts reasonably incurred by such person in any action or proceeding, including any action by or in our right, on account of any services undertaken by such person on behalf of our company or that person’s status as a member of our Board of Directors to the maximum extent allowed under Delaware law.

Sublease Agreement

In April 2021, we entered into a sublease agreement with Viridian Therapeutics, Inc. (“Viridian”), which was subsequently amended in November 2021 and April 2022. Entities associated with Fairmount Funds Management LLC beneficially own more than 5% of our capital stock and Viridian’s capital stock. Under the terms of the sublease, which is scheduled to expire in June 2022, we paid Viridian an aggregate of $0.1 million in rent payments plus $0.1 million in related taxes and lease operating costs. The lease was negotiated on an

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arm’s-length basis and was a market rate transaction on terms that we believed were no less favorable than would have been reached with an unrelated third party. Although we did not consider this transaction to be material to us, we are disclosing it in accordance with our related person transactions policy described below.

Related Person Transaction Policy

Our Board has adopted a written related person transactions policy providing that transactions with us and any related person (as defined above) must be approved by our Audit Committee. Pursuant to this policy, the Audit Committee has the primary responsibility for reviewing and approving or disapproving “related person transactions,” which are transactions between us and related persons in which the aggregate amount involved exceeds or may be expected to exceed $120,000 and in which a related person has or will have a direct or indirect material interest. In determining whether to approve any such transaction, the Audit Committee will review and consider:

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OTHER MATTERS

Stockholder Proposals and Director Nominations for Next Year’s Annual Meeting

Pursuant to Rule 14a-8 of the Exchange Act, stockholders who wish to submit proposals for inclusion in the proxy statement for the 2023 Annual Meeting of Stockholders must send such proposals to our Corporate Secretary at the address set forth on the first page of this Proxy Statement. Such proposals must be received by us as of the close of business (6:00 p.m. Eastern Time) on December 27, 2022 and must comply with Rule 14a-8 of the Exchange Act. Such proposals may or may not be included in the proxy statement.

As set forth in our bylaws, if a stockholder intends to make a nomination for director election or present a proposal for other business (other than pursuant to Rule 14a-8 of the Exchange Act) at the 2023 Annual Meeting of Stockholders, the stockholder’s notice must be received by our Corporate Secretary at the address set forth on the first page of this Proxy Statement no earlier than the 120th day and no later than the 90th day before the anniversary of the last annual meeting; provided, however, that if the date of the annual meeting is more than 30 days before or more than 60 days after such anniversary date, the stockholder’s notice must be delivered not later than the close of business on the later of the 90th day prior to such annual meeting or the 10th day following the date on which the first public announcement of the date of such annual meeting is made by the Company. Therefore, unless the 2023 Annual Meeting of Stockholders is more than 30 days before or more than 60 days after the anniversary of the Annual Meeting, notice of proposed nominations or proposals (other than pursuant to Rule 14a-8 of the Exchange Act) must be received by our Corporate Secretary no earlier than February 7, 2023 and no later than the close of business (6:00 p.m. Eastern Time) on March 9, 2023. Any such director nomination or stockholder proposal must be a proper matter for stockholder action and must comply with the terms and conditions set forth in our bylaws. If a stockholder fails to meet these deadlines and fails to satisfy the requirements of Rule 14a-4 of the Exchange Act, we may exercise discretionary voting authority under proxies we solicit to vote on any such proposal as we determine appropriate. In addition to satisfying the deadlines in the advance notice provisions of our bylaws, a stockholder who intends to solicit proxies in support of nominees submitted under these advance notice provisions for the 2023 Annual Meeting must provide the notice required under Rule 14a-19 of the Exchange Act to our Corporate Secretary in writing not later than the close of business (6:00 p.m. Eastern Time) on April 10, 2023.

Delivery of Documents to Stockholders Sharing an Address

A number of brokerage firms have adopted a procedure approved by the SEC called “householding.” Under this procedure, certain stockholders who have the same address and do not participate in electronic delivery of proxy materials will receive only one copy of the proxy materials, including this Proxy Statement, the Notice and our Annual Report on Form 10-K for the year ended December 31, 2021, until such time as one or more of these stockholders notifies us that they wish to receive individual copies. This procedure helps to reduce duplicate mailings and save printing costs and postage fees, as well as natural resources. If you received a “householding” mailing this year and would like to have additional copies of the proxy materials mailed to you, please send a written request to our Corporate Secretary at the address set forth on the first page of this Proxy Statement, or call (617) 945-5576, and we will promptly deliver the proxy materials to you. Please contact your broker if you received multiple copies of the proxy materials and would prefer to receive a single copy in the future, or if you would like to opt out of “householding” for future mailings.

Availability of Additional Information

We will provide, free of charge, a copy of our Annual Report on Form 10-K for the year ended December 31, 2021, including exhibits, on the written or oral request of any stockholder of the Company. Please send a written request to our Corporate Secretary at the address set forth on the first page of this Proxy Statement or call the number above.

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SCAN TO VIEW MATERIALS & VOTE COGENT BIOSCIENCES, INC. 200 CAMBRIDGE PARK DRIVE, SUITE 2500 CAMBRIDGE, MASSACHUSETTS 02140 VOTE BY INTERNET Before The Meeting - Go to www.proxyvote.com or scan the QR Barcode above Use the Internet to transmit your voting instructions and for electronic delivery of information up until 11:59 p.m. Eastern Time on June 6, 2022. Have your proxy card in hand when you access the web site and follow the instructions to obtain your records and to create an electronic voting instruction form. During The Meeting - Go to www.virtualshareholdermeeting.com/COGT2022 You may attend the meeting via the Internet and vote during the meeting. Have the information that is printed in the box marked by the arrow available and follow the instructions. VOTE BY PHONE - 1-800-690-6903 Use any touch-tone telephone to transmit your voting instructions up until 11:59 p.m. Eastern Time on June 6, 2022. Have your proxy card in hand when you call and then follow the instructions. VOTE BY MAIL Mark, sign and date your proxy card and return it in the postage-paid envelope we have provided or return it to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717. TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS: D81860-P73370 KEEP THIS PORTION FOR YOUR RECORDS THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED. DETACH AND RETURN THIS PORTION ONLY COGENT BIOSCIENCES, INC. For Withhold For All nominee(s), To withhold mark authority “For to All vote Except” for any and individual write the All All Except number(s) of the nominee(s) on the line below. The Board of Directors recommends you vote FOR ALL director nominees listed in Proposal 1 and FOR Proposal 2. 1. Election of Class I Directors for terms expiring in 2025 Nominees: 01) Karen Ferrante, M.D. For Against Abstain 02) Matthew E. Ros 2. Ratification of the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the year ending December 31, 2022. NOTE: Such other business as may properly come before the meeting or any adjournment or postponement thereof. Please sign exactly as your name(s) appear(s) hereon. When signing as attorney, executor, administrator, or other fiduciary, please give full title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or partnership name by authorized officer. Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting of Stockholders to Be Held on June 7, 2022: The Proxy Statement and Annual Report for the year ended December 31, 2021 are available at www.proxyvote.com. D81861-P73370 COGENT BIOSCIENCES, INC. Annual Meeting of Stockholders June 7, 2022 9:00 AM, ET This proxy is solicited by the Board of Directors The undersigned hereby appoint(s) Andrew Robbins, John Green and Evan Kearns, or any of them, as proxies, each with the power to appoint his substitute, and hereby authorize(s) them to represent and to vote, as designated on the reverse side of this form, all of the shares of common stock of COGENT BIOSCIENCES, INC. that the undersigned is/are entitled to vote at the Annual Meeting of Stockholders to be held at 9:00 AM, ET on June 7, 2022, live via the Internet, at www.virtualshareholdermeeting.com/COGT2022, and any adjournment or postponement thereof. This proxy, when properly executed and returned, will be voted in the manner directed herein. If no such direction is made but the card is signed, this proxy will be voted in accordance with the Board of Directors' recommendations and in the discretion of the proxies with respect to such other business as may properly come before the meeting or any adjournment or postponement thereof. In the event that any of the nominees named on the reverse side of this form are unavailable for election or unable to serve, the shares represented by this proxy may be voted for a substitute nominee selected by the Board of Directors. Continued and to be signed on reverse side