Proxy Statement (Form DEF 14A)

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.)

ANAPTYSBIO, INC.

(Name of Registrant as Specified In Its Charter)

N/A

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

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

June 29, 2026

Dear Stockholder:

You are cordially invited to attend the 2026 Annual Meeting of Stockholders of AnaptysBio, Inc. ("AnaptysBio") to be held at AnaptysBio's corporate office at 10770 Wateridge Circle, Suite 210, San Diego, CA 92121, on Tuesday, August 11, 2026 at 9:00 a.m. (Pacific Time).

The Securities and Exchange Commission rules allow companies to furnish proxy materials to stockholders over the Internet. We have elected to do so, thus reducing the environmental impact and lowering the costs of printing and distributing proxy materials without impacting your timely access to this important information. On or about June 29, 2026, we expect to mail to stockholders a Notice of Internet Availability of Proxy Materials containing instructions on how to access our proxy statement for our 2026 Annual Meeting of Stockholders and our Annual Report on Form 10-K for the year ended December 31, 2025 to stockholders. The Notice of Internet Availability of Proxy Materials also provides instructions on how to vote through the Internet or by telephone and includes instructions on how to receive paper copies of the proxy materials by mail, if desired.

The matters to be acted upon at the meeting are described in the accompanying notice of annual meeting and proxy statement.

Your vote is important.

Whether or not you plan to attend the meeting in person, please vote on the Internet or by telephone, or request, sign and return a proxy card to ensure that your shares are represented at the meeting.

ANAPTYSBIO, INC.

10770 Wateridge Circle, Suite 210

San Diego, California 92121

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held Tuesday, August 11, 2026

To Our Stockholders:

NOTICE IS HEREBY GIVEN that the 2026 Annual Meeting of Stockholders of AnaptysBio, Inc. ("AnaptysBio") will be held at AnaptysBio's corporate office at 10770 Wateridge Circle, Suite 210, San Diego, California 92121, on Tuesday, August 11, 2026 at 9:00 a.m. (Pacific Time).

We are holding the meeting for the following purposes, which are more fully described in the accompanying proxy statement:

In addition, stockholders may be asked to consider and vote upon such other business as may properly come before the meeting or any adjournment or postponement thereof.

Only stockholders of record at the close of business on June 22, 2026 are entitled to notice of, and to vote at, the meeting and any adjournments thereof. For ten days prior to the meeting, a complete list of the stockholders entitled to vote at the meeting will be available for examination by any stockholder for any purpose relating to the meeting during ordinary business hours at our headquarters.

Your vote as an AnaptysBio stockholder is very important. Each share of stock that you own represents one vote.

Whether or not you expect to attend the meeting, we encourage you to read the proxy statement and vote through the Internet or by telephone, or request, sign and return your proxy card as soon as possible, so that your shares may be represented at the meeting. For specific instructions on how to vote your shares, please refer to the section entitled "General Information About the Meeting" in the proxy statement and the instructions on the Notice of Internet Availability of Proxy Materials. Only stockholders entitled to vote, or their duly authorized representatives, are entitled to attend the meeting. If you intend to attend the meeting in person, you must email [email protected] no later than 5:00 p.m. on August 4, 2026 to confirm your attendance.

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ANAPTYSBIO, INC.

10770 Wateridge Circle, Suite 210

San Diego, California 92121

PROXY STATEMENT FOR THE 2026 ANNUAL MEETING OF STOCKHOLDERS

To Be Held Tuesday, August 11, 2026

INFORMATION ABOUT SOLICITATION AND VOTING

The accompanying proxy is solicited on behalf of AnaptysBio, Inc.'s ("AnaptysBio") board of directors ("Board") for use at AnaptysBio's 2026 Annual Meeting of Stockholders ("Annual Meeting") to be held at AnaptysBio's corporate office at 10770 Wateridge Circle, Suite 210, San Diego, California 92121, on Tuesday, August 11, 2026 at 9:00 a.m. (Pacific Time), and any adjournment or postponement thereof.

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GENERAL PROXY INFORMATION

Voting Rights

Each holder of shares of common stock is entitled to one vote for each share of common stock held as of the close of business on June 22, 2026, the record date. You may vote all shares owned by you at such date, including (i) shares held directly in your name as the stockholder of record and (ii) shares held for you as the beneficial owner in street name through a broker, bank, trustee or other nominee. Dissenters' rights are not applicable to any of the matters being voted on.

Stockholder of Record: Shares Registered in Your Name. If, on June 22, 2026, your shares were registered directly in your name with our transfer agent, Equiniti Trust Company, LLC, then you are considered the stockholder of record with respect to those shares. As a stockholder of record, you may vote at the meeting, or vote in advance through the Internet or by telephone, or if you request to receive paper proxy materials by mail, by filling out and returning the proxy card.

Beneficial Owner: Shares Registered in the Name of a Broker or Nominee. If on June 22, 2026, your shares were held in an account with a brokerage firm, bank or other nominee, then you are the beneficial owner of the shares held in street name. As a beneficial owner, you have the right to direct your broker on how to vote the shares held in your account, and your broker has enclosed or provided voting instructions for you to use in directing it on how to vote your shares. Because the brokerage firm, bank or other nominee that holds your shares is the stockholder of record, if you wish to attend the meeting and vote your shares you must obtain a valid proxy from the firm that holds your shares giving you the right to vote the shares at the meeting.

Broker Non-Votes

For banks, brokers or other nominee accounts, they are entitled to vote shares held for a beneficial owner on "routine" matters without instructions from the beneficial owner of those shares. For "non-routine" matters, the beneficial owner of such shares is required to provide instructions to the bank, broker or other nominee in order for them to be entitled to vote the shares held for the beneficial owner. If you hold shares beneficially in street name and do not provide your broker or other agent with voting instructions, your shares may constitute "broker non-votes." A "broker non-vote" occurs when shares held by a broker that are represented at the meeting are not voted with respect to a particular proposal because the broker has not received voting instructions from its client(s) with respect to such shares on how to vote and does not have or did not exercise discretionary authority to vote on the matter. 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, 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. If a stockholder does not return voting instructions to their broker on how to vote their shares of common stock, such broker may be prevented from voting, or may otherwise choose not to vote, such shares held by such broker, resulting in broker non-votes with respect to such shares. To make sure that your vote is counted, you should instruct your broker to vote your shares of common stock, following the procedures provided by your broker.

Required Vote

Proposal 1: Each director will be elected by a plurality of the votes present in person or represented by proxy at the meeting and entitled to vote on the election of directors. This means that the two individuals nominated for election to the Board at the meeting receiving the highest number of "FOR" votes will be elected. You may either vote "FOR" one or more of the nominees or "WITHHOLD" your vote with respect to any or all of the nominees. You may not cumulate votes in the election of directors.

Proposal 2: Approval of the ratification of the appointment of our independent registered public accounting firm will be obtained if the number of votes cast "FOR" the proposal at the meeting exceeds the number of votes cast "AGAINST" the proposal.

Proposal 3: The advisory vote on named executive officer compensation will be obtained if the number of votes cast "FOR" the proposal at the meeting exceeds the number of votes cast "AGAINST" the proposal. This vote is advisory and non-binding in nature.

Proposal 4: Approval of the amendment of our 2017 Equity Incentive Plan will be obtained if the number of votes cast "FOR" the proposal at the meeting exceeds the number of votes cast "AGAINST" the proposal.

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A proxy submitted by a stockholder may indicate that the shares represented by the proxy are not being voted (stockholder withholding) with respect to a particular matter. In addition, a broker may not be permitted to vote on shares held in street name on a particular matter in the absence of instructions from the beneficial owner of the stock (broker non-vote). The shares subject to a proxy which are not being voted on a particular matter because of either stockholder withholding or abstaining or broker non-votes will count for purposes of determining the presence of a quorum, but are not treated as votes cast for or against a matter and, therefore, will have no effect on the election of directors, the ratification of the appointment of KPMG LLP, the advisory vote on our named executive officer compensation, or the amendment of our 2017 Equity Incentive Plan. Proposal 2 is considered a routine proposal and is subject to the discretionary vote of the broker.

Recommendations of the Board on Each of the Proposals Scheduled to be Voted on at the Meeting

The Board recommends that you vote "FOR" the election of each of the Class III directors named in this proxy statement (Proposal 1), "FOR" the ratification of the appointment of KPMG LLP as our independent registered public accounting firm for the fiscal year ending June 30, 2027 (Proposal 2), "FOR" the non-binding advisory vote on named executive officer compensation (Proposal 3), and "FOR" the approval of the amendment of our 2017 Equity Incentive Plan (Proposal 4).

Voting Instructions; Voting of Proxies

If you are a stockholder of record, you may:

Votes submitted through the Internet or by telephone must be received by 11:59 p.m., Eastern Time, on August 10, 2026. Submitting your proxy, whether by telephone, through the Internet or by mail if you request or received a paper proxy card, will not affect your right to vote in person should you decide to attend the meeting. If you are not the stockholder of record, please refer to the voting instructions provided by your nominee to direct it how to vote your shares.

For Proposal 1, you may vote "FOR" each of the nominees to the Board or you may "WITHHOLD" your vote from any nominee you specify. A "WITHHOLD" vote will have the same effect as a vote to abstain.

For Proposal 2, Proposal 3, and Proposal 4, you may vote "FOR" or "AGAINST" or "ABSTAIN" from voting. Your vote is important. Whether or not you plan to attend the meeting, we urge you to vote by proxy to ensure that your vote is counted.

All proxies will be voted in accordance with the instructions specified on the proxy card. If you sign a physical proxy card and return it without instructions as to how your shares should be voted on a particular proposal at the meeting, your shares will be voted in accordance with the recommendations of our Board stated above.

If you received a Notice of Internet Availability, please follow the instructions included on the notice on how to access your proxy card and vote by telephone or through the Internet. If you do not vote and you hold your shares in street name, and your broker does not have discretionary power to vote your shares, your shares may constitute "broker non-votes" (as described above) and will not be counted in determining the number of shares necessary for approval of the proposals. However, shares that constitute broker non-votes will be counted for the purpose of establishing a quorum for the meeting.

If you receive more than one proxy card or Notice of Internet Availability, your shares are registered in more than one name or are registered in different accounts. To make certain all of your shares are voted, please follow the instructions included on the Notice of Internet Availability on how to access each proxy card and vote each proxy card by telephone or through the Internet. If you requested or received paper proxy materials by mail, please complete, sign and return each proxy card to ensure that all of your shares are voted.

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Expenses of Soliciting Proxies

We will pay the expenses associated with soliciting proxies. Following the original distribution and mailing of the solicitation materials, we or our agents may solicit proxies by mail, electronic mail, telephone, facsimile, by other similar means, or in person. Our directors, officers and other employees, without additional compensation, may solicit proxies personally or in writing, by telephone, e-mail or otherwise. Following the original distribution and mailing of the solicitation materials, we will request brokers, custodians, nominees and other record holders to forward copies of those materials to persons for whom they hold shares and to request authority for the exercise of proxies. In such cases, we, upon the request of the record holders, will reimburse such holders for their reasonable expenses. If you choose to access the proxy materials and/or vote through the Internet, you are responsible for any Internet access charges you may incur.

Revocability of Proxies

A stockholder of record who has given a proxy may revoke it at any time before the closing of the polls by the inspector of election at the meeting by:

Please note, however, that if your shares are held of record by a brokerage firm, bank or other nominee and you wish to revoke a proxy, you must contact that firm to revoke or change any prior voting instructions.

Electronic Access to the Proxy Materials

The Notice of Internet Availability will provide you with instructions regarding how to:

Choosing to receive your future proxy materials by email will reduce the impact of our annual meetings of stockholders on the environment and lower the costs of printing and distributing our proxy materials. If you choose to receive future proxy materials by email, you will receive an email next year with instructions containing a link to those materials and a link to the proxy voting site. Your election to receive proxy materials by email will remain in effect until you terminate it.

Voting Results

Voting results will be tabulated and certified by the inspector of election appointed for the meeting. The preliminary voting results will be announced at the meeting. The final results will be tallied by the inspector of election and filed with the SEC in a current report on Form 8-K within four business days of the meeting.

Implications of being a "Smaller Reporting Company"

We are a "smaller reporting company," as defined in Rule 12b-2 under the Exchange Act of 1934, as amended (the "Exchange Act"), and have elected to provide in this proxy statement certain scaled disclosures permitted under the Exchange Act for smaller reporting companies. We will remain a "smaller reporting company" until the fiscal year following the determination that our voting and non-voting common shares held by non-affiliates is at least $250 million measured on the last business day of our second fiscal quarter, or our annual revenues are at least $100 million during the most recently completed fiscal year and our voting and non-voting common shares held by non-affiliates is at least $700 million measured on the last business day of our second fiscal quarter. Accordingly, the information contained in this proxy statement and the matters to be voted on at the Annual Meeting may not be as extensive as the information and proxy proposals submitted by other public companies that are not smaller reporting companies.

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CORPORATE GOVERNANCE STANDARDS AND DIRECTOR INDEPENDENCE

We are committed to good corporate governance practices. These practices provide an important framework within which our Board and management pursue our strategic objectives for the benefit of our stockholders.

Corporate Governance Guidelines

Our Board has adopted Corporate Governance Guidelines that set forth expectations for directors, director independence standards, board committee structure and functions and other policies for the governance of the company. Our Corporate Governance Guidelines are available without charge on the investor relations section of our website at http://ir.anaptysbio.com.

Board Composition and Leadership Structure

The positions of Chief Executive Officer and Chairman of our Board are held by two different individuals. Daniel Faga has served as our President and Chief Executive Officer since August 3, 2023 and was our Interim President and Chief Executive Officer from March 21, 2022 through August 2, 2023. John Orwin currently serves as Chairman of our Board and Oleg Nodelman has been elected to serve as Chairman of our Board, effective immediately following the Annual Meeting. This separated structure allows our Chief Executive Officer to focus on our day-to-day business while our Chairman leads our Board in its fundamental role of providing advice to, and independent oversight of, management. Our Board believes such separation is appropriate, as it enhances the accountability of the Chief Executive Officer to the Board and strengthens the independence of the Board from management.

Board's Role in Risk Oversight

Our Board believes that open communication between management and the Board is essential for effective risk management and oversight. Our Board meets with our Chief Executive Officer and other members of the senior management team at quarterly Board meetings, where, among other topics, they discuss strategy and risks in the context of reports from the management team and evaluate the risks inherent in significant transactions. While our Board is ultimately responsible for risk oversight, our board committees assist the Board in fulfilling its oversight responsibilities in certain areas of risk. The audit committee assists our Board in fulfilling its oversight responsibilities with respect to risk management in the areas of cybersecurity assessment and internal control over financial reporting and disclosure controls and procedures. The compensation committee assists our Board in assessing risks created by the incentives inherent in our compensation policies. The nominating and corporate governance committee assists our Board in fulfilling its oversight responsibilities with respect to the management of corporate, legal and regulatory risk.

Cybersecurity Risk Oversight

Securing the information of participants in our team members, stakeholders, and other third parties is important to us. Moreover, our Board recognizes the critical importance of maintaining the trust and confidence of our investors, business partners and employees. We have adopted physical, technological, and administrative controls on data security, and have a defined procedure for data incident detection, containment, response, and remediation. While everyone at our company plays a part in managing these risks, oversight responsibility is shared by our Board, our audit committee, and management. Additional information relating to cybersecurity and information security is contained in the section titled "Cybersecurity" in our Annual Report on Form 10-K for the year ended December 31, 2025.

Director Independence

Our common stock is listed on The Nasdaq Global Select Market ("Nasdaq"). Under Nasdaq rules, independent directors must comprise a majority of a listed company's Board. In addition, Nasdaq rules require that, subject to specified exceptions, each member of a listed company's audit, compensation and nominating and corporate governance committees be independent. Under Nasdaq rules, a director will only qualify as an "independent director" if, in the opinion of that company's Board, that person does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director.

Audit committee members must also satisfy the independence criteria set forth in Rule 10A-3 under the Exchange Act. In order to be considered independent for purposes of Rule 10A-3, a member of an audit committee of a listed company may not, other than in his or her capacity as a member of the audit committee, the Board or any other board committee: (i) accept, directly or indirectly, any consulting, advisory or other compensatory fee from the listed company or any of its subsidiaries; or (ii) be an affiliated person of the listed company or any of its subsidiaries. Additionally, compensation

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committee members must not have a relationship with the listed company that is material to the director's ability to be independent from management in connection with the duties of a compensation committee member.

Our Board has undertaken a review of the independence of each director and considered whether each director has a material relationship with us that could compromise his or her ability to exercise independent judgment in carrying out his or her responsibilities. As a result of this review, our Board determined that Dennis Fenton, Ph.D., Rita Jain, M.D., Magda Marquet, Ph.D., Hollings Renton, John P. Schmid, John Orwin, Oleg Nodelman and J. Anthony Ware, M.D., representing eight of the nine persons who served as directors in 2025, were "independent directors" as defined under the applicable rules and regulations of the SEC, and the listing requirements and rules of Nasdaq. Mr. Faga is not independent given his role as our President and Chief Executive Officer. Also as a result of this review, our Board determined that Ms. Gray, who was appointed as a director on March 26, 2026, and Mr. Hughes, who was appointed as a director on May 11, 2026, are "independent directors" as defined under the applicable rules and regulations of the SEC and the listing requirements and rules of Nasdaq. In making these determinations, our Board reviewed and discussed information provided by the directors and us with regard to each director's business and personal activities and relationships as they may relate to us and our management, including the beneficial ownership of our capital stock by each non-employee director and the transactions involving them described in the section entitled "Certain Relationships and Related-Party Transactions."

Committees of Our Board

Our Board has an audit committee, a compensation committee, and a nominating and corporate governance committee, each of which has the composition and responsibilities described below. Members serve on these committees until their resignation or until otherwise determined by our Board. Each committee operates under a charter approved by our Board. Copies of each committee's charter are posted on the investor relations section of our website at http://ir.anaptysbio.com.

Audit Committee

Our audit committee is composed of Ms. Gray, Mr. Orwin and Mr. Schmid. Mr. Schmid is the chairperson of our audit committee. Ms. Gray, Mr. Orwin and Mr. Schmid each meet the requirements for independence under the current Nasdaq listing standards and SEC rules and regulations. Each member of our audit committee is financially literate. In addition, our Board has determined that Mr. Schmid is an "audit committee financial expert" as defined in Item 407(d)(5)(ii) of Regulation S-K promulgated under the Securities Act. This designation does not impose any duties, obligations or liabilities that are greater than are generally imposed on members of our audit committee and our Board. Our audit committee is responsible for, among other things:

Compensation Committee

Our compensation committee is composed of Mr. Orwin and Mr. Schmid. Mr. Orwin is the chairperson of our compensation committee. The composition of our compensation committee meets the requirements for independence under the current Nasdaq listing standards and SEC rules and regulations. Each member of this committee is (i) an outside director, as defined pursuant to Section 162(m) of the Internal Revenue Code of 1986, as amended (the "Code"), and (ii) a non-employee director, as defined in Rule 16b-3 promulgated under the Exchange Act. Our compensation committee is responsible for, among other things:

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Our compensation committee retained an independent compensation consultant, Alpine Rewards ("Alpine Rewards"), a national compensation consulting firm, to assist in structuring our executive officer and director compensation on an ongoing basis.

Alpine Rewards provided our compensation committee with market data and analyses from a peer group of biotechnology companies with product candidates in a similar stage of development and similar financial and size characteristics. Alpine Rewards has not provided us or our compensation committee with any other services that would compromise their independence or pose a conflict of interest.

Nominating and Corporate Governance Committee

Our nominating and corporate governance committee is composed of Mr. Nodelman, Mr. Orwin and Mr. Renton. Mr. Renton is the chairperson of our nominating and corporate governance committee. The composition of our nominating and corporate governance committee meets the requirements for independence under the current Nasdaq listing standards and SEC rules and regulations. Our nominating and corporate governance committee is responsible for, among other things:

Code of Business Conduct and Ethics

Our Board has adopted a Code of Conduct and Ethics that applies to all of our employees, officers and directors, including our Chief Executive Officer, Chief Financial Officer and other executive and senior financial officers. The full text of our Code of Conduct is posted on the investor relations section of our website at http://ir.anaptysbio.com by clicking on "Governance." Any amendments or waivers of our Code of Conduct pertaining to a member of our Board or one of our executive officers will be disclosed on our website at the above-referenced address.

Insider Trading Policy

We have adopted an Insider Trading Policy governing the purchase, sale, and other dispositions of our securities that applies to all of our personnel, including directors, officers, employees, and other covered persons. The Insider Trading Policy also provides that the Company will not transact in its own securities unless in compliance with U.S. federal and state securities laws. We believe that our Insider Trading Policy is reasonably designed to promote compliance with insider trading laws, rules and regulations, and listing standards applicable to the Company. A copy of the Insider Trading Policy is filed as Exhibit 19.1 to our Annual Report on Form 10-K, filed on March 3, 2026.

Hedging and Pledging Prohibitions

Under our Insider Trading Policy, our employees, executive officers, and members of our Board are prohibited from engaging in certain speculative transactions including, among other things: (i) acquiring, selling, or trading in any interest or position relating to the future price of our securities, such as a put option, a call option, or a short sale (including a short sale "against the box"); (ii) engaging in hedging or monetization transactions, including prepaid variable forward contracts,

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equity swaps, collars and exchange funds; or (iii) purchasing our securities on margin, borrowing against any account in which our securities are held, or pledging our securities as collateral for a loan.

Timing of Equity Grants

Compensation Committee Interlocks and Insider Participation

None of our executive officers has served as a member of the board of directors, or as a member of the compensation or similar committee, of any entity that has one or more executive officers who served on our Board or compensation committee during the year ended December 31, 2025.

Board and Committee Meetings and Attendance

The Board and its committees meet regularly throughout the year and also hold special meetings and act by written consent from time to time. During 2025, the Board held 14 meetings, including by videoconference, the audit committee held 4 meetings, our compensation committee held 4 meetings and the nominating and corporate governance committee held 2 meetings. During 2025, none of the directors attended fewer than 75% of the aggregate of the total number of meetings held by the Board during his or her tenure and the total number of meetings held by all committees of the Board on which such director served during his or her tenure. The independent members of the Board also meet separately without management directors on a regular basis to discuss such matters as the independent directors consider appropriate.

Board Attendance at Annual Stockholders' Meeting

Nine directors were in attendance at our 2025 annual meeting of stockholders. We invite and encourage each member of our Board to attend our annual meetings of stockholders; however, we do not have a formal policy regarding attendance of annual meetings by the members of our Board.

Communication with Directors

Stockholders and interested parties who wish to communicate with our Board, non-management members of our Board as a group, a committee of the Board or a specific member of our Board (including our Chairman) may do so by letters addressed to the attention of our Corporate Secretary, AnaptysBio, Inc., 10770 Wateridge Circle, Suite 210, San Diego, CA 92121.

All communications by letter addressed to the attention of our Corporate Secretary will be reviewed by the Corporate Secretary and provided to the members of the Board unless such communications are unsolicited items, sales materials and other routine items and items unrelated to the duties and responsibilities of the Board.

Board Diversity

Due to the complex nature of our business, the Board believes it is important to consider diversity of race, ethnicity, gender, sexual orientation, age, education, cultural background, and professional experiences in evaluating board candidates in order to provide practical insights and diverse perspectives.

Considerations in Evaluating Director Nominees

The nominating and corporate governance committee is responsible for identifying, evaluating and recommending candidates to the Board for board membership. A variety of methods are used to identify and evaluate director nominees, with the goal of maintaining and further developing a diverse, experienced and highly qualified Board. Candidates may come to our attention through current members of our Board, professional search firms, stockholders or other persons.

The nominating and corporate governance committee will recommend to the Board for selection all nominees to be proposed by the Board for election by the stockholders, including approval or recommendation of a slate of director

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nominees to be proposed by the Board for election at each annual meeting of stockholders, and will recommend all director nominees to be appointed by the Board to fill interim director vacancies.

Our Board encourages selection of directors who will contribute to the Company's overall corporate goals. The nominating and corporate governance committee may from time to time review and recommend to the Board the desired qualifications, expertise and characteristics of directors, including such factors as business experience, diversity and personal skills in life sciences and biotechnology, finance, marketing, financial reporting and other areas that are expected to contribute to an effective Board. Exceptional candidates who do not meet all of these criteria may still be considered. In evaluating potential candidates for the Board, the nominating and corporate governance committee considers these factors in the light of the specific needs of the Board at that time.

In addition, under our Corporate Governance Guidelines, a director is expected to spend the time and effort necessary to properly discharge such director's responsibilities. Accordingly, a director is expected to regularly attend meetings of the Board and committees on which such director sits, and to review prior to meetings material distributed in advance for such meetings. Thus, the number of other public company boards and other boards (or comparable governing bodies) on which a prospective nominee is a member, as well as his or her other professional responsibilities, will be considered. Under our Corporate Governance Guidelines, there are no limits on the number of three-year terms that may be served by a director. However, in connection with evaluating recommendations for nomination for reelection, the nominating and corporate governance committee considers director tenure. We value diversity on a company-wide basis, but have not adopted a specific policy regarding board diversity.

Stockholder Recommendations for Nominations to the Board

The nominating and corporate governance committee will consider properly submitted stockholder recommendations for candidates for our Board who meet the minimum qualifications as described above. The nominating and corporate governance committee does not intend to alter the manner in which it evaluates candidates, including the minimum criteria set forth above, based on whether or not the candidate was recommended by a stockholder. A stockholder of record can nominate a candidate for election to the Board by complying with the procedures in Article I, Section 1.12 of our Bylaws. Any eligible stockholder who wishes to submit a nomination should review the requirements in the Bylaws on nominations by stockholders. Any nomination should be sent in writing to our Corporate Secretary, AnaptysBio, Inc., 10770 Wateridge Circle, Suite 210, San Diego, CA 92121. Submissions must include the full name of the proposed nominee, complete biographical information, a description of the proposed nominee's qualifications as a director, other information regarding the nominee and proposing stockholder as specified in our Bylaws, and certain representations regarding the nomination. Any such submission must be accompanied by the written consent of the proposed nominee to be named as a nominee and to serve as a director if elected. These candidates are evaluated at meetings of the nominating and corporate governance committee, and may be considered at any point during the year. If any materials are provided by a stockholder in connection with the recommendation of a director candidate, such materials are forwarded to the nominating and corporate governance committee.

All proposals of stockholders that are intended to be presented by such stockholder at an annual meeting of stockholders must be in writing and notice must be delivered to the Corporate Secretary at our principal executive offices not later than the close of business on the 75th day nor earlier than the close of business on the 105th day prior to the first anniversary of the preceding year's annual meeting. Stockholders are also advised to review our Bylaws, which contain additional requirements with respect to advance notice of stockholder proposals and director nominations. In addition to satisfying the foregoing requirements under the Bylaws, to comply with the universal proxy rules, stockholders who intend to solicit proxies in support of director nominees other than the Company's nominees for the 2027 Annual Meeting of Stockholders must provide notice that sets forth the information required by Rule 14a-19 under the Exchange Act.

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PROPOSAL NO. 1
ELECTION OF CLASS III DIRECTORS

Our Board is divided into three classes. Each class serves for three years, with the terms of office of the respective classes expiring in successive years. Directors and director nominees in Class III will stand for election at this meeting. The terms of office of directors in Class I and Class II do not expire until the annual meetings of stockholders to be held in 2027 and 2028, respectively.

Our Class III directors, whose terms will expire at this Annual Meeting, are Mr. Renton and Mr. Schmid.

At the recommendation of our nominating and corporate governance committee, our Board proposes that each of Mr. Renton and Mr. Schmid, each an incumbent Class III director, be elected as a Class III director for a three-year term expiring at the annual meeting of stockholders to be held in 2029 and until such director's successor is duly elected and qualified or until such director's earlier resignation or removal.

Each director will be elected by a plurality of the votes present in person or represented by proxy at the meeting and entitled to vote on the election of directors. This means that the two individuals nominated for election to the Board at the meeting receiving the highest number of "FOR" votes will be elected. You may either vote "FOR" one or more nominees or "WITHHOLD" your vote with respect to any or all of the individuals nominated for election to the Board. A "WITHHOLD" vote will have the same effect as an abstention. You may not cumulate votes in the election of directors. Shares represented by proxies will be voted "FOR" the election of each of the Class III nominees, unless the proxy is marked to withhold authority to so vote. If any nominee for any reason is unable to serve, the proxies may be voted for such substitute nominee as the proxy holders, who are officers of our company, determine. Each nominee has consented to being named in this proxy statement and to serve if elected. Proxies may not be voted for more than two directors.

Nominees to the Board

The nominees and their ages are provided in the table below. Additional biographical information for each nominee is set forth in the text below the table.

Hollings Renton has served as a member of our Board since June 2015. Mr. Renton previously served as the Chief Executive Officer and President of Onyx Pharmaceuticals, Inc. from 1993 to 2008 and as the chairperson of its board of directors from 2000 to 2008. Before joining Onyx Pharmaceuticals, Mr. Renton served as the President and Chief Operating Officer of Chiron Corporation, a pharmaceutical company, from 1991 to 1993, following its acquisition of Cetus Corporation. Mr. Renton served as the President of Cetus Corporation from 1990 to 1991, as Chief Operating Officer from 1987 to 1990, and as Chief Financial Officer from 1983 to 1987. Mr. Renton previously served on the board of directors of Zymeworks, Inc., a publicly traded company, from 2017 to 2024, and Portola Pharmaceuticals, Inc., a publicly traded company, from March 2010 to June 2020. Mr. Renton received his M.B.A. from the University of Michigan and his B.S. in Mathematics from Colorado State University. Our Board believes that Mr. Renton's extensive industry experience and board memberships provide him with the qualifications and skills to serve on our Board.

John P. Schmid has served as a member of our Board since June 2015. Mr. Schmid served as Chief Financial Officer of Auspex Pharmaceuticals, Inc. from September 2013 to June 2015. Before joining Auspex Pharmaceuticals, Mr. Schmid co-founded Trius Therapeutics, a publicly traded biopharmaceutical company, where he served as the Chief Financial Officer from June 2004 until its merger with Cubist Pharmaceuticals, Inc., in September 2013. Before he joined Trius Therapeutics, Mr. Schmid served as the Chief Financial Officer at Gene Formatics, Inc., a private biotechnology company, from 1998 to 2003, and at Endonetics, a private medical device company, from 1995 to 1998. Mr. Schmid currently serves as a member of the board of directors of the publicly traded company Design Therapeutics Inc., a pharmaceutical company, First Tracks Biotherapeutics, Inc., a publicly traded pharmaceutical company, Bright Peak Therapeutics, a private biotechnology company, and BlossomHill Therapeutics, Inc., a private pharmaceutical company. In the last five years, Mr. Schmid has

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previously served on the boards of directors of Helix Acquisition Corp. and Helix Acquisition Corp. II, both special purpose acquisition companies, Neos Therapeutics, Poseida Therapeutics, Inc., and Xeris Pharmaceuticals, all pharmaceutical companies. Mr. Schmid received his M.B.A. from the University of San Diego and his B.A. from Wesleyan University. Our Board believes that Mr. Schmid's extensive industry experience and executive positions at multiple biopharmaceutical companies qualify him to serve on our Board.

Continuing Directors

The directors who are serving or who have been appointed for terms that end following the meeting, and their ages (as of the date of this Proxy Statement), occupations and length of board service are provided in the table below. Additional biographical information for each nominee is set forth in the text below the table.

Daniel Faga has served as a member of our Board since November 2021, and has served as our President and Chief Executive Officer since August 2023. Mr. Faga previously served as our Interim President and Chief Executive Officer from March 2022 to August 2023. From January 2020 to November 2021, Mr. Faga served as Chief Operating Officer at Mirati Therapeutics, responsible for leading the company's corporate strategy, finance, legal and other business operations. Prior to joining Mirati, Mr. Faga served as the Chief Business Officer for Spark Therapeutics, Inc. from May 2016 through December 2019, where he was responsible for leading the company's corporate strategy, portfolio and new product planning, patient advocacy, business development, alliance management, asset & program management and corporate communications functions. From July 2009 until April 2016, Mr. Faga was a Managing Director at Centerview Partners, an investment banking and advisory firm, where he served as a founding member of Centerview's healthcare advisory practice. Prior to Centerview, Mr. Faga worked at Merrill Lynch in its healthcare investment banking group and as a management consultant in the Life Sciences Practice at PRTM. Mr. Faga earned a B.S. in Engineering from Cornell University and an M.B.A. in Health Care Management from The Wharton School at the University of Pennsylvania. Our Board believes that Mr. Faga's extensive industry experience and executive experience provides him with the qualifications and skills to serve on our Board.

Oleg Nodelman has served as a member of our Board since April 2021 and will be Chairman of our Board effective immediately following the Annual Meeting. Mr. Nodelman has served as the Founder and Portfolio Manager of EcoR1 Capital LLC, a biotech-focused investment advisory firm established in 2013, and one of our principal stockholders, since its inception. Previously, Mr. Nodelman served as a Portfolio Manager at BVF Partners from 2001 to 2012. Mr. Nodelman earned a B.S.F.S. in Science and Technology from Georgetown University, School of Foreign Service in 1999. Mr. Nodelman currently serves on the board of directors of both Galapagos NV and Zymeworks, and previously served on the board of directors of Prothena Corporation plc from 2019 to 2024, Nuvation Bio Inc. from February 2021 to December 2023 and Panacea Acquisition Corp. II from April 2020 to February 2021. Our Board believes that Mr. Nodelman's extensive industry experience provides him with the qualifications and skills to serve on our Board.

Susannah Gray has served as a member of our Board since March 2026. Ms. Gray also currently serves on the board of directors of Maravai LifeSciences Holdings, Inc., a life science company, 4D Molecular Therapeutics, Inc., a biotech company, and Theravance BioPharma, Inc., a biopharmaceutical company. Ms. Gray previously served on the board of directors of Morphic Holding, Inc. (the parent company of Morphic Therapeutic, Inc.), a biotech company, from April 2021 to August 2024 and Apria, Inc., a healthcare company, from May 2021 to March 2022, when Apria, Inc. was acquired by Owens & Minor, Inc. Ms. Gray served as the Chief Financial Officer of Royalty Pharma Management LLC ("Royalty Pharma"), a buyer of pharmaceutical royalties, from January 2005 to December 2018. Ms. Gray was promoted to Executive Vice President of Finance and Strategy in December 2018 and retired from Royalty Pharma in September 2019. Prior to

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Royalty Pharma, Ms. Gray served as a managing director and senior analyst covering the healthcare sector of CIBC World Markets' high yield group from 2002 to 2004 and previously served in similar roles at Merrill Lynch and Chase Securities (predecessor of J.P. Morgan Securities). Ms. Gray holds a B.A. in Social Studies from Wesleyan University and an MBA from Columbia University. Our Board believes that Ms. Gray's extensive executive experience in the pharmaceutical industry, as well as her financial expertise, qualify her to serve on our Board.

John Orwin has served as a member of our Board and Chairman of our Board since September 2023. Mr. Orwin has been a venture partner at Samsara BioCapital, L.P., a venture capital group, since 2024, and currently serves as the chair of the board of directors of the publicly traded First Tracks Biotherapeutics, Inc., a pharmaceutical company, Nested Therapeutics, Inc., a privately held company, serves on the board of directors of Ambrosia Biosciences, Inc., a privately held company, and as executive chairman of the board of directors of Agni Bio, Inc., a privately held company. Mr. Orwin served as the President and Chief Executive Officer of Atreca, Inc. from April 2018 to June 2024. He also has served as a member of the board of directors of CARGO Therapeutics, Inc. since August 2022, and Travere Therapeutics, Inc. since March 2017. He previously served as a member of the boards of directors of Seagen, Inc. from January 2014 until its acquisition by Pfizer Inc. in December 2023 and Array BioPharma, Inc. from November 2012 to July 2019. Mr. Orwin received a B.A. in Economics from Rutgers, The State University of New Jersey and an M.B.A. from New York University. Our Board believes that Mr. Orwin's extensive industry experience and executive positions at multiple biopharmaceutical companies qualify him to serve on our Board.

Owen Hughes has served as a member of our Board since May 2026. Mr. Hughes has served as Chief Executive Officer of Xoma Royalty Corp., a publicly traded royalty aggregator, since January 2024, and prior to that served as Executive Chairman of the Board of Xoma Royalty Corp. and Interim Chief Executive Officer from January 2023 through January 2024. Mr. Hughes has served as the Chief Executive Officer of Sail Bio, Inc., a private biotechnology company focused on addressing toxic proteinopathies, a rare genetic kidney disease, since February 2022 and served as the Chief Executive Officer and co-founder of Cullinan Therapeutics, Inc. (formerly Cullinan Oncology, Inc.), a publicly-traded oncology company, from September 2017 to October 2021. Previously, Mr. Hughes served as the Chief Business Officer and Head of Corporate Development at Intarcia Therapeutics, Inc., a biotechnology company focused on type II diabetes, from February 2013 to August 2017. Prior to his operating roles, Mr. Hughes spent 16 years on Wall Street in various capacities, including roles at Brookside Capital, an operating division of Bain Capital, and Pyramis Global Advisors, a Fidelity Investments Company. Mr. Hughes has served as the Chairman of the Board of Ikena Oncology, Inc., a formerly publicly-traded oncology company, since December 2022 and as a member of the Board of Directors of C4 Therapeutics, a publicly traded biopharmaceutical company, since December 2023. Mr. Hughes served on the Board of Radius Health, Inc., a formerly publicly-traded biopharmaceutical company, from April 2013 to August 2022, until its sale to Gurnet Point Capital and Patient Square Capital; Translate Bio, Inc., a messenger RNA therapeutics company, from July 2016 until its acquisition by Sanofi in September 2021; and FS Development Corp. II, a special purpose acquisition company sponsored by Foresite Capital, from February 2021 to December 2021. Mr. Hughes received a B.A. in History from Dartmouth College. Our Board believes that Mr. Hughes' extensive executive experience in the pharmaceutical industry, in particular in the royalty financing space, qualifies him to serve on our Board.

There are no familial relationships among any of our directors and executive officers.

Non-Employee Director Compensation

The following table presents the total compensation for each person who served as a non-employee member of our Board in the year ended December 31, 2025. Mr. Faga is not paid any fees or other compensation for services as a member of our Board. For Mr. Faga's compensation as our President and Chief Executive Officer, see the section below entitled "Executive Compensation."

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Our compensation arrangements for non-employee directors are reviewed periodically by our compensation committee and our Board. In addition, Alpine Rewards provided a competitive analysis of director compensation levels, practices and design features as compared to the general market as well as to our compensation peer group. Based on this analysis, there were no changes in compensation for 2025.

Cash Compensation

Pursuant to our non-employee director compensation policy each of our non-employee directors is provided with an annual cash compensation. Cash compensation is paid quarterly in arrears, and is prorated for partial service during a quarter.

The table below summarizes the cash compensation of our non-employee directors for 2025 pursuant to our director compensation policy, as well as the changes from 2024.

Equity Compensation

Our non-employee director compensation policy is designed to enable us to attract and retain, on a long-term basis, highly qualified non-employee directors. Under our non-employee director compensation policy, each non-employee director will be eligible to receive the following amounts for their service on our Board:

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All equity awards held by our non-employee directors will accelerate in full upon a change in control.

OUR BOARD RECOMMENDS A VOTE "FOR" THE ELECTION OF EACH OF THE NOMINATED CLASS III DIRECTORS.

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PROPOSAL NO. 2
RATIFICATION OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Our audit committee has selected KPMG LLP as our principal independent registered public accounting firm to perform the audit of our consolidated financial statements for the fiscal year ending June 30, 2027. KPMG LLP audited our financial statements for the fiscal years ended December 31, 2025 and 2024, and will audit our financial statements for the fiscal year ended June 30, 2026. We expect that representatives of KPMG LLP will be present at the Annual Meeting, will be able to make a statement if they so desire and will be available to respond to appropriate questions.

At the Annual Meeting, the stockholders are being asked to ratify the appointment of KPMG LLP as our independent registered public accounting firm for the fiscal year ending June 30, 2027. Our audit committee is submitting the selection of KPMG LLP to our stockholders because we value our stockholders' views on our independent registered public accounting firm and as a matter of good corporate governance. If this proposal does not receive the affirmative approval of a majority of the votes cast for or against the proposal, the audit committee would reconsider the appointment. Notwithstanding its selection and even if our stockholders ratify the selection, our audit committee, in its discretion, may appoint another independent registered public accounting firm at any time during the year if the audit committee believes that such a change would be in our best interests and the interests of our stockholders.

The following table presents fees for services rendered by KPMG LLP for the years ended December 31, 2025 and 2024 (in thousands).

Principal Accountant Fees and Services

The audit committee must pre-approve all services to be performed for us by KPMG LLP. Pre-approval is granted usually at regularly scheduled meetings of the audit committee. The audit committee also may approve the additional unanticipated services by either convening a special meeting of the audit committee or acting by unanimous written consent. During 2025, all services billed by KPMG LLP were pre-approved by the audit committee in accordance with this policy.

These services may include audit services, audit-related services, tax services and other services. Pre-approval is detailed as to the particular service or category of services and is generally subject to a specific budget. The independent registered public accounting firm and management are required to periodically report to the audit committee regarding the extent of services provided by the independent registered public accounting firm in accordance with this pre-approval, and the fees for the services performed to date. Our audit committee may also pre-approve particular services on a case-by-case basis. All of the services relating to the fees described in the table above were approved by our audit committee.

OUR BOARD RECOMMENDS A VOTE "FOR" APPROVAL OF PROPOSAL NO. 2.

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REPORT OF THE AUDIT COMMITTEE

The information contained in the following report of the audit committee is not considered to be "soliciting material," "filed" or incorporated by reference in any past or future filing by us under the Securities Exchange Act of 1934, as amended, or the Securities Act of 1933, as amended, unless and only to the extent that we specifically incorporate it by reference.

The audit committee has reviewed and discussed with our management and KPMG LLP our audited consolidated financial statements as of and for the year ended December 31, 2025. The audit committee has also discussed with KPMG LLP the matters required to be discussed by applicable standards of the Public Company Accounting Oversight Board (United States).

The audit committee has received and reviewed the written disclosures and the letter from KPMG LLP required by applicable requirements of the Public Company Accounting Oversight Board regarding the independent accountant's communications with the audit committee concerning independence and has discussed with KPMG LLP its independence.

Based on the review and discussions referred to above, the audit committee recommended to our Board that the audited consolidated financial statements as of and for the year ended December 31, 2025 be included in our Annual Report on Form 10-K for the year ended December 31, 2025 for filing with the Securities and Exchange Commission.

Submitted by the Audit Committee

John P. Schmid (Chair)

Susannah Gray

John Orwin

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PROPOSAL NO. 3

NON-BINDING ADVISORY VOTE ON COMPENSATION OF OUR NAMED EXECUTIVE OFFICERS

We are seeking a non-binding, advisory stockholder vote on the compensation awarded to our named executive officers for the fiscal year ended December 31, 2025, known as a "Say-on-Pay" vote.

The Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (the "Dodd-Frank Act") enables our stockholders to vote to approve, on an advisory, non-binding basis, the compensation of our named executive officers as disclosed in this proxy statement in accordance with Section 14A of the Exchange Act. At our 2025 annual meeting of stockholders, we asked our stockholders to express a preference for the frequency of our Say-on-Pay vote. The majority of our stockholders voted to hold the Say-on-Pay vote on an annual basis, and therefore, based on that vote, we present this vote every year.

As described in detail in the "Executive Compensation" section of this proxy statement, our compensation program is designed to reward our executive officers at a level consistent with our overall strategic and financial performance and to provide remuneration sufficient to attract, retain and motivate them to exert their best efforts and create a successful company. Our philosophy is to tie a greater percentage of an executive officer's compensation to stockholder returns and to keep cash compensation at a competitive level while providing the opportunity to be well-rewarded through equity if we perform well over time. We believe that our executive compensation program, with its balance of short-term incentives (including base salary and annual cash incentives tied to performance measures) and long-term incentives (including equity awards) reward sustained performance, is aligned with long-term stockholder interests. Stockholders are encouraged to read the Executive Compensation section of this proxy statement.

Based on the above, we request that stockholders approve, on a non-binding advisory basis, the compensation of our named executive officers as described in this proxy statement pursuant to the following resolution:

RESOLVED, that the compensation paid to AnaptysBio's named executive officers, as disclosed in this proxy statement, including the "Executive Compensation" section, compensation tables and narrative discussion, is hereby APPROVED.

Vote Required

Approval of named executive officer compensation requires the approval of a majority of the votes present or represented by proxy and voted for or against the matter.

As an advisory vote, this proposal is non-binding. Although the vote is non-binding, our Board and compensation committee value the opinions of our stockholders and will consider the outcome of the vote when making future compensation decisions for our named executive officers.

OUR BOARD RECOMMENDS A VOTE "FOR" APPROVAL OF PROPOSAL NO. 3.

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PROPOSAL NO. 4

APPROVE AMENDMENT TO OUR 2017 EQUITY INCENTIVE PLAN

Our 2017 Equity Incentive Plan was adopted in connection with our initial public offering in 2017. On June 17, 2025, our stockholders approved the amendment and restatement of our 2017 Plan. We refer to our 2017 Plan as amended and restated as the "2017 Plan" in this proxy statement.

We are asking our stockholders to approve a limited amendment ("Amendment No. 1") to our 2017 Plan (as amended by Amendment No. 1, the "Amended Plan"). Our Board has approved the Amended Plan, subject to stockholder approval. If the Amended Plan is approved by our stockholders, it will become effective on the date of such stockholder approval (the "Amendment Effective Date"). If the Amended Plan is not approved, our current 2017 Plan will remain as-is and will terminate pursuant to its terms on January 12, 2027.

What the Amended Plan Does

No Increase to Share Reserve

We are not seeking stockholder approval to authorize any additional shares for the Amended Plan as the existing share reserve is expected to be sufficient to meet our needs for the foreseeable future.

Rationale For and Reasons Why the Board Recommends a Vote FOR the Amended Plan

Equity Compensation is a Critical Element of Our Compensation Program

The use of equity compensation, including the grant of options and RSUs, has been an important part of our overall compensation philosophy. We believe that the adoption of the Amended Plan is in the best interests of the Company and our stockholders for the following reasons:

If the Amended Plan is not approved by our stockholders, our 2017 Plan will remain in effect and then terminate on January 12, 2027, which is the expiration of its term. The term extension is necessary to allow us to continue making equity grants to directors and employees.

Current 2017 Plan Information

As of June 1, 2026:

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The above information reflects the effects of the Spin-Off (as defined below), which was completed on April 20, 2026. See "Impact of the 2026 Spin-Off on Executive Officers and Executive Compensation Arrangements" below for more information.

Summary of the Amended Plan

The following is a summary of the principal features of the Amended Plan. This summary, however, does not purport to be a complete description of all of the provisions of the Amended Plan. It is qualified in its entirety by reference to the full text of the 2017 Plan, a copy of which is attached hereto as Annex A, and Amendment No. 1 to the 2017 Plan, a copy of which is attached hereto as Annex B.

Background; Purpose

The 2017 Plan was adopted by our Board on January 12, 2017 and became effective on January 24, 2017 (the "Original Effective Date"). The Amended Plan was adopted by the Board on June 20, 2026. If the Amended Plan is approved by stockholders, it will terminate on June 20, 2036, ten years after the Board approved the amendment. The purpose of the Amended Plan is to provide incentives to attract, retain and motivate eligible persons whose present and potential contributions are important to our success.

Eligibility

Employees, officers, directors, consultants, independent contractors and advisors of the Company or any parent, subsidiary or affiliate of the Company are eligible to receive awards. As of June 1, 2026, we had two executive officers (as such term is defined under Rule 16a-1(f)) and six non-employee directors who would be eligible to participate in the Amended Plan.

Administration

The Amended Plan will be administered by our compensation committee, all of the members of which are non-employee directors under applicable federal securities laws and outside directors as defined under applicable federal tax laws. Our compensation committee will act as the plan administrator and have the authority to construe and interpret the Amended Plan, grant awards, determine the terms and conditions of awards and make all other determinations necessary or advisable for the administration of the Amended Plan (subject to the limitations set forth in the Amended Plan). However, our Board establishes the terms for the grant of awards to non-employee directors as discussed above under "Proposal No. 1 Election of Class III Directors-Non-Employee Director Compensation".

Share Reserve

The number of shares authorized under the Amended Plan will remain unchanged from the current 2017 Plan. The Amended Plan does not include an "evergreen" provision, and there will be no automatic annual increases thereunder.

In addition, the following shares of our common stock will be available for grant and issuance under our Amended Plan:

With respect to awards granted under the Amended Plan (including prior to its amendment):

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Shares that otherwise become available for grant and issuance shall not include shares subject to awards that initially became available because of the Company's substitution or assumption of awards granted by another company in connection with an acquisition of such company, or otherwise, as permitted under the Amended Plan.

Equitable Adjustments

In the event of a change in our common stock via a stock dividend, extraordinary dividend or distribution (whether in cash, shares, or other property, other than a regular cash dividend), recapitalization, stock split, reverse stock split, subdivision, combination, consolidation, reclassification, spin-off, or similar change in the capital structure of the company without consideration, proportionate adjustments will be made to (a) the number and class of shares reserved for issuance and future grant under the Amended Plan (including the maximum number and class of ISOs (as defined below)), (b) the exercise prices of and number and class of shares subject to outstanding options and stock appreciation rights, (c) the number and class of shares subject to outstanding awards (other than options and stock appreciation rights), and (d) the number and class of shares that may be granted as awards to non-employee directors, subject to any required action by the Board or the stockholders of the Company.

Equity Awards

The Amended Plan will permit us to grant the following types of awards:

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Performance Factors

The compensation committee may establish performance goals from the performance criteria set forth in the Amended Plan, which include the following: profit before tax; billings; revenue; net revenue; earnings (which may include earnings before interest and taxes, earnings before taxes, net earnings, stock-based compensation expenses, depreciation, and amortization); operating income; operating margin; operating profit; controllable operating profit or net operating profit; net profit; gross margin; operating expenses or operating expenses as a percentage of revenue; net income; earnings per share; total stockholder return; market share; return on assets or net assets; the Company's stock price; growth in stockholder value relative to a pre-determined index; return on equity; return on invested capital; cash flow (including free cash flow or operating cash flows); cash conversion cycle; economic value added; individual confidential business objectives; contract awards or backlog; overhead or other expense reduction; credit rating; strategic plan development and implementation; succession plan development and implementation; improvement in workforce diversity; customer indicators and/or satisfaction; new product invention or innovation; attainment of research and development milestones; improvements in productivity; bookings; attainment of objective operating goals and employee metrics; sales; expenses; balance of cash, cash equivalents, and marketable securities; completion of an identified special project; completion of a joint venture or other corporate transaction; employee satisfaction and/or retention; research and development expenses; working capital targets and changes in working capital; and any other metric that is capable of measurement as determined by the compensation committee. The compensation committee may provide for one or more equitable adjustments to the performance criteria, including to preserve compensation committee's original intent regarding such criteria at the time of the initial award grant, such as but not limited to, adjustments in recognition of unusual or non-recurring items such as acquisition related activities or changes in applicable accounting rules.

Stockholder Approval Required for Repricing, Exchange and Buyout

The compensation committee may not, without the approval of our stockholders, reprice options or stock appreciation rights, including pursuant to an exchange program whereby cash or new awards are issued in exchange for the surrender and cancellation of any, or all, outstanding awards.

Insider Trading; Clawback Policy

Each participant who receives an award will comply with any policy adopted by the Company from time to time covering transactions in our securities by employees, officers and/or directors.

All awards will be subject to clawback or recoupment pursuant to any compensation clawback or recoupment policy adopted by the Board or required by law during the term of the participant's employment or other service, and in addition to any other remedies available under such policy and applicable law, we may require the cancellation of outstanding awards and the recoupment of any gains realized with respect to awards.

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Restrictions on Dividends and Dividend Equivalents

A participant will have no right to payment of stock dividends or stock distributions with respect to unvested shares, and any such dividends or stock distributions will be accrued and paid only at such time, if any, as such unvested shares become vested shares and are no longer subject to restrictions and risk of forfeiture.

Change in Control

If we undergo a Corporate Transaction (as defined in the Amended Plan), any or all outstanding awards may be assumed or replaced by the successor corporation, which assumption or replacement shall be binding on all participants. In the alternative, the successor corporation may substitute equivalent awards or provide substantially similar consideration to participants as was provided to stockholders (after taking into account the existing provisions of the awards). The successor corporation may also issue, in place of outstanding shares of the Company held by the participant, substantially similar shares or other property subject to repurchase restrictions no less favorable to the participant. In the event such successor or acquiring corporation (if any) refuses to assume, convert, replace or substitute awards, as provided above, pursuant to a Corporate Transaction, then notwithstanding any other provision in the Amended Plan to the contrary, such awards will expire on such transaction at such time and on such conditions as the Board will determine; the Board (or, the compensation committee, if so designated by the Board) may, in its sole discretion, accelerate the vesting of such awards in connection with a Corporate Transaction. In addition, in the event such successor or acquiring corporation (if any) refuses to assume, convert, replace or substitute awards, as provided above, pursuant to a Corporate Transaction, the compensation committee will notify the participant in writing or electronically that such award will be exercisable for a period of time determined by the compensation committee in its sole discretion, and such award will terminate upon the expiration of such period. Awards need not be treated similarly in a Corporate Transaction and treatment may vary from award to award and/or from participant to participant.

In the event of a Corporate Transaction, the vesting of all awards granted to our non-employee directors will accelerate and such awards will become exercisable (as applicable) in full upon the consummation of such event at such times and on such conditions as the compensation committee determines.

Foreign Award Recipients

In order to comply with the laws in other countries in which we and our subsidiaries and affiliates operate or have employees or other individuals eligible for awards, the compensation committee will have the power and authority to modify the terms and conditions of any award granted to individuals outside the United States to comply with applicable foreign laws, establish subplans and modify exercise procedures and other terms and procedures, and take any action that the compensation committee determines to be necessary or advisable to comply with any local governmental regulatory exemptions or approvals.

Transferability of Awards

Unless the compensation committee provides otherwise, the Amended Plan does not allow for the transfer of awards, other than by will or the laws of descent and distribution, and generally only the recipient of an award may exercise it during his or her lifetime.

Grants to Non-Employee Directors

Non-employee directors are eligible to receive any type of award offered under the Amended Plan except ISOs. Awards to non-employee directors under the Amended Plan may be automatically made pursuant to a policy adopted by the Board, or made from time to time as determined in the discretion of the Board. The Amended Plan limits the aggregate amount of cash compensation and the grant date fair value of awards that may be paid or granted to a non-employee director during any fiscal year of service to $1,000,000 for the director's first fiscal year of service and $750,000 for each subsequent fiscal year of service, effective for fiscal years commencing on or after July 1, 2026.

Amendment and Termination

The Board is permitted to amend or terminate the Amended Plan at any time, subject to stockholder approval where required. In any event, no termination or amendment of the Amended Plan or any outstanding award may adversely affect

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any then outstanding award without the consent of the participant, unless such termination or amendment is necessary to comply with applicable law, regulation or rule.

The 2017 Plan originally became effective on the Original Effective Date. Unless earlier terminated as provided in the Amended Plan, the Amended Plan will become effective on the Amendment Effective Date and will terminate ten years from the date the Amended Plan was approved by the board.

Federal Income Tax Consequences

The following is a general summary under current law of certain U.S. federal income tax consequences to participants who are citizens or individual residents of the United States relating to the types of equity awards that may be granted under the Amended Plan. This summary deals with the general tax principles and is provided only for general information. Certain kinds of taxes, such as foreign taxes, state and local income taxes, payroll taxes and the alternative minimum tax, are not discussed.

In each of the foregoing cases, we will generally have a corresponding deduction at the time the participant recognizes ordinary income, subject to Section 162(m) of the Internal Revenue Code and the relevant income tax regulations. Section 162(m) places a limit of $1 million on the amount of compensation that we may deduct as a business expense in any year with respect to certain of our most highly paid executive officers. We may from time to time pay compensation to our executives that may not be deductible if the compensation committee believes that doing so is in the best interests of our stockholders.

ERISA Information

The Amended Plan is not subject to the provisions of the Employee Retirement Income Security Act of 1974, as amended.

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New Plan Benefits

Our named executive officers and members of our Board have an interest in this proposal by virtue of them being eligible to receive equity awards under the Amended Plan. No awards have been granted that are contingent on the approval of the Amended Plan. Future awards under the Amended Plan to executive officers, employees or other eligible participants are discretionary and cannot be determined at this time. Currently, our non-employee directors are entitled to receive cash and equity compensation for their service as directors as described above under "Proposal No. 1 Election of Class III Directors-Non-Employee Director Compensation".

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Historical Plan Benefits Table

The following table sets forth the number of shares subject to stock options or restricted or performance stock unit awards granted under the 2017 Plan from its Original Effective Date through December 31, 2025, excluding shares underlying options or awards that were granted under the 2017 Plan that expired unexercised or were canceled:

(1) Dr. Lizzul and Mr. Mulroy separated from the Company on April 20, 2026.

Vote Required

The approval of the Amended Plan requires the approval of a majority of the votes present or represented by proxy and voted for or against the matter.

OUR BOARD RECOMMENDS A VOTE "FOR" APPROVAL OF PROPOSAL NO. 4.

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth certain information with respect to the expected beneficial ownership of shares of our common stock as of June 1, 2026 for:

We have determined beneficial ownership in accordance with the rules of the SEC, and the information is not necessarily indicative of beneficial ownership for any other purpose. Except as indicated by the footnotes below, we believe, based on information furnished to us, that the persons and entities named in the table below have sole voting and sole investment power with respect to all shares of common stock that they beneficially owned, subject to applicable community property laws.

Applicable percentage ownership is based on 29,302,112 shares of common stock issued and outstanding as of June 1, 2026. In computing the number of shares of common stock beneficially owned by a person and the percentage ownership of that person, we deemed to be outstanding all shares of common stock subject to options held by that person or entity that are currently exercisable or that will become exercisable within 60 days of June 1, 2026. We did not deem these shares outstanding, however, for the purpose of computing the percentage ownership of any other person. Unless otherwise indicated, the address of each beneficial owner listed in the table on the following page is c/o AnaptysBio, Inc., 10770 Wateridge Circle, Suite 210, San Diego, CA 92121.

* Represents beneficial ownership of less than one percent.

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EXECUTIVE OFFICERS

The following table sets forth the names, ages and certain other information about our executive officers as of the date of this filing:

Mr. Faga's biographical information is set forth above under "Proposal No. 1 Election of Class III Directors-Non-Employee Director Compensation".

Mr. Murphy was appointed as Chief Financial Officer on May 11, 2026. His biographical information is set forth below.

On April 20, 2026, we distributed all outstanding shares of common stock of our subsidiary First Tracks Biotherapeutics, Inc. ("First Tracks Biotherapeutics") to holders of our stock as a pro rata dividend. In connection with the Spin-Off (as defined below), Eric Loumeau, the former Chief Legal Officer, separated from the Company as an executive officer and Paul Lizzul, M.D., Ph.D., the former Chief Medical Officer and Dennis Mulroy, the former Chief Financial Officer, separated from the Company, effective as of April 20, 2026.

Our executive officers are appointed by, and serve at the discretion of, our Board. There are no family relationships among any of our directors or executive officers.

None of our directors, executive officers, significant employees or control persons has been involved in any legal proceeding listed in Item 401(f) of Regulation S-K in the past 10 years.

Christopher M. Murphy has served as our Chief Financial Officer since May 2026. Prior to joining us, Mr. Murphy served as Chief Financial and Business Officer of Third Harmonic Bio, Inc. from January 2024 through December 2025. Prior to that, Mr. Murphy held positions of increasing responsibility at Horizon Therapeutics PLC, or Horizon, from March 2014 to May 2020, serving as Vice President of Business Development from March 2014 to November 2015, Group Vice President of Corporate Development from November 2015 to October 2017, Group Vice President of Operations, Inflammation Business Unit from October 2017 to June 2018, and most recently as Group Vice President, Commercial Operations and Analytics from June 2018 to May 2020. Prior to Horizon, Mr. Murphy held positions of increasing responsibility in the Life Sciences Investment Banking Group at JMP Securities LLC, or JMP, from July 2008 to March 2014, serving most recently as a Director from February 2014 to March 2014. Prior to JMP, Mr. Murphy served as a Consultant in the Litigation and Investigation Group of Navigant Consulting, Inc. from July 2006 to June 2008. Mr. Murphy holds a B.B.A. in Finance from the University of Notre Dame.

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EXECUTIVE COMPENSATION

This overview and narrative ("Compensation Disclosure") describes the key elements of our executive compensation program and compensation decisions for our named executive officers for 2025. This Compensation Disclosure is intended to be read in conjunction with the tables that immediately follow this section, which provide additional compensation information for our named executive officers. As a "smaller reporting company" as defined in Item 10(f)(1) of Regulation S-K, we are not required to include a Compensation Discussion and Analysis section and have elected to comply with the scaled disclosure requirements applicable to smaller reporting companies. However, we believe the additional narrative disclosure with respect to our executive compensation program will provide our stockholders with further information regarding our company and our executive compensation program and practices and therefore will assist in their consideration of the non-binding advisory vote with respect to named executive officer compensation that will be included in our proxy statement for the upcoming annual meeting.

For the fiscal year ended December 31, 2025, our "named executive officers" ("NEOs") were:

On April 20, 2026, we completed the previously announced separation (the "Spin-Off") of First Tracks Biotherapeutics from the Company. The impact of the Spin-Off on our executive compensation program is described below under "Impact of the 2026 Spin-Off on Named Executive Officers and Executive Compensation Arrangements." In connection with the Spin-Off, Eric Loumeau separated from the Company as an executive officer, and Paul Lizzul, M.D., Ph.D. and Dennis Mulroy separated from the Company, effective as of April 20, 2026. Mr. Loumeau continued to provide services as a consultant following his separation.

2025 Corporate Performance Summary

We made progress on several programs and corporate milestones during 2025, including the following:

Executive Compensation Policies and Practices

We endeavor to maintain sound compensation governance standards consistent with our executive compensation policies and practices. Our compensation committee evaluates our executive compensation program on a regular basis (and no less than annually) to ensure that it is consistent with our short-term and long-term goals given the dynamic nature of our business and the market in which we compete for executive talent. The following summarizes our executive compensation and related policies and practices:

What We Do

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What We Do Not Do

Stockholder Advisory Vote to Approve Named Executive Officer Compensation

At our 2025 Annual Meeting of Stockholders, we conducted a non-binding stockholder advisory vote on the compensation of our named executive officers (commonly known as a "Say-on-Pay" vote). Our Board and our compensation committee consider the results of the Say-on-Pay vote in determining the compensation of our executive officers, including our named executive officers. At our 2025 Annual Meeting of Stockholders, approximately 73% of the votes cast approved our executive compensation program.

We value the opinion of our stockholders. Our Board and our compensation committee will continue to consider the result of the Say-on-Pay vote, as well as feedback received throughout the year, when making compensation decisions for our executive officers.

In addition, consistent with the recommendation of our Board and the preference of our stockholders as reflected in the non-binding stockholder advisory vote on the frequency of future Say-on-Pay votes held at our 2025 Annual Meeting of Stockholders, we continue to hold future Say-on-Pay votes on an annual basis.

Executive Compensation Philosophy & Objectives

The principal objectives of our executive compensation program, policies, and practices are to:

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Our compensation committee believes an appropriate, well-designed compensation program should align executive interests with the drivers of growth and stockholder returns by supporting the achievement of our primary business goals. Further, the compensation program must enable us to attract and retain employees whose talents, expertise and leadership can drive our success and sustained growth in long-term stockholder value.

Our executive compensation program has reflected our industry and life-cycle stage, including the fact that we are a biotechnology company whose product candidates are in pre-clinical and clinical development and remain subject to regulatory approval. As a result, our revenues have been limited. Our historical compensation programs have focused on long-term incentive compensation in the form of equity awards relative to cash compensation. This approach seeks to place a substantial portion of executive compensation at risk by rewarding our named executive officers, in a manner comparable to our stockholders, for achieving our business and financial objectives.

In addition, we have a performance-oriented compensation philosophy focused on creating long-term value. Our executive compensation program is heavily weighted toward variable, at-risk performance-based bonuses, long-term equity awards, and performance-based equity awards.

We maintain an annual performance-based cash bonus plan for our named executive officers. Payments under this cash bonus plan are based primarily on our level of achievement of pre-established corporate performance goals to tie compensation of our named executive officers to achievement of key corporate objectives, which will ultimately create stockholder value. We also provide long-term equity awards to motivate our named executive officers in a manner that directly aligns their interest with our long-term strategic direction and the interests of our stockholders, as well as providing our executive officers with an incentive to remain with us as their equity awards vest.

When considering the total variable pay-mix for our executive officers, we seek to design and implement a competitive executive compensation program that combines both cash and incentive elements based on annual performance objectives and long-term equity elements that will be flexible and complementary to meet our compensation objectives. Our compensation committee has not adopted any formal policies or guidelines for allocating compensation between current and long-term compensation, between cash and non-cash compensation, or among different forms of non-cash compensation. The factors taken into account by our compensation committee in setting the level of fixed and variable cash compensation and non-cash compensation are described in greater detail below in "Compensation-Setting Process" and "Compensation Elements."

Compensation-Setting Process

Our compensation committee has overall responsibility for overseeing our compensation and benefits policies generally, and overseeing and evaluating the compensation plans, policies and practices applicable to our Chief Executive Officer and other named executive officers.

In carrying out its responsibilities, our compensation committee evaluates our compensation policies and practices with a focus on the degree to which these policies and practices reflect our executive compensation philosophy, develops strategies and makes decisions that it believes further our philosophy or align with developments in best compensation practices, and reviews the performance of our named executive officers when making decisions with respect to their compensation.

In discharging its responsibilities, our compensation committee engages an external compensation consultant to assist it by providing information, analysis and other advice relating to our executive compensation program. Our compensation committee also takes into consideration input from our Chief Executive Officer (other than with respect to himself) and other members of our management team.

Our compensation committee's authority, duties, and responsibilities are further described in its charter, which is reviewed annually and revised and updated as warranted. The charter is available on our company website. Our compensation

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committee also retains an independent compensation consultant (as described below) to provide support in its review and assessment of our executive compensation program.

Updated Competitive Positioning

During 2024, our compensation committee directed Alpine Rewards to refresh our compensation peer group for 2025. In evaluating the companies to comprise the compensation peer group at that time, Alpine Rewards considered the following criteria: (i) biotechnology and pharmaceutical companies with therapeutic similarity in inflammation, immune-oncology, and other antibody-based therapies; (ii) with lead drugs in phase II or III or pending approval; (iii) ~50 - ~250 employees (~0.5 to ~2.5 of our current headcount); and (iv) a market capitalization of 0.33x to 3.0x our market capitalization.

Based on a review of the analysis prepared by Alpine Rewards in December 2024, our compensation committee approved an updated compensation peer group, referred to as the 2025 peer group, consisting of the following companies:

Our compensation committee used the 2025 peer group as a reference in December 2024 for its compensation decisions regarding 2025.

The compensation practices of the peer group were the primary guide used by our compensation committee to compare the competitiveness of each compensation element and overall compensation levels (base salary, target annual cash bonus opportunities, and long-term incentive compensation) for purposes of decisions relating to compensation.

Our compensation committee reviews our compensation peer group each year (or more frequently if there have been significant changes to either our business model or market capitalization) and makes adjustments to its composition if warranted, taking into account changes in both our business and the businesses of the companies in the peer group.

Compensation Elements

In 2025, the principal elements of our executive compensation program, and the objective for each element, were as follows:

Base Salary

Base salary represents the fixed portion of the compensation of our named executive officers and is an important element of compensation intended to attract and retain highly-talented individuals by providing an amount of fixed pay that compensates executives for their scope of responsibility, skill-level and performance.

In December 2024, our compensation committee reviewed the base salaries of our named executive officers, taking into consideration a competitive market analysis prepared by its compensation consultant using the then-current peer group and the other factors described in "Compensation-Setting Process" above. Following this review, our compensation committee

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approved base salary increases for each of our named executive officers, effective January 1, 2025, to bring their base salaries to levels that were comparable to those of similarly-situated executives at the companies in our compensation peer group.

The base salaries paid to our named executive officers during 2025 are set forth in the "Executive Compensation 2025 Summary Compensation Table" below.

Annual Performance-Based Cash Bonuses

We use an annual performance-based cash bonus plan to motivate our employees, including our named executive officers, to achieve our key annual corporate business objectives. In December 2024, our compensation committee and Board adopted an annual cash bonus plan for 2025 (the "2025 Cash Bonus Plan") to provide financial incentives related to the achievement of principal goals set forth in our 2025 annual operating plan. The 2025 Cash Bonus Plan provided for bonus payments to be funded based on our level of achievement with respect to corporate performance goals (as described below).

For purposes of the 2025 Cash Bonus Plan, cash bonus payments were based upon a specific percentage of each participant's base salary. In December 2024, our compensation committee reviewed the target annual cash bonus opportunities of our named executive officers, taking into consideration the factors described in "Compensation-Setting Process" above and approved the target annual cash bonus opportunities for each of the named executive officers.

The table below shows the 2025 target annual cash bonus opportunities for our named executive officers, expressed as a percentage of base salary, which targets remain unchanged from 2024:

Corporate Performance Goals

Participants in the 2025 Cash Bonus Plan were eligible to receive a bonus payment based upon the attainment of one or more corporate performance goals that were selected and approved by our compensation committee and which related to financial and operational metrics that were important to us. The corporate performance component of the 2025 Cash Bonus Plan was to be funded based on our actual results for the year as evaluated against these performance goals and account for 100% of the NEOs total bonus opportunity.

In December 2024, our compensation committee and Board approved corporate performance goals in each of the following categories for purposes of the 2025 Cash Bonus Plan:

i Rosnilimab RA - (a) Read out RA Phase 2b top-line results in Q1 2025 and (b) Enable Phase 3 development plan;

ii Rosnilimab UC - (a) Read out UC Phase 2 top-line results by Q4 2025 and (b) Enable Phase 3 development plan;

iii Early Portfolio and Expansion - (a) ANB033 (CD122 antagonist): on track to read out top-line Phase 1b results in celiac disease in 2026; (b) ANB101 (BDCA2 modulator): on track for Phase 1 results in 2026; (c) conduct certain business development activities;

iv Capitalization - Manage operating expenses within approved budget, extend cash runway, conduct certain business development activities; and

v Organizational Talent and Culture - Retain, develop and recruit leadership to support future growth expectations and ensure consistent company culture, vision and values.

Each corporate performance goal was evaluated and selected according to our compensation committee's assessment of its relative importance to the execution of our annual business plan. Our primary focus was on our clinical development and research programs, as they are key drivers of our business. We allocated the remainder of the bonus opportunity to managing operations such as finance, retaining, developing and recruiting leadership to support future growth, and ensuring consistent company culture, which are also necessary for the execution of our business plan.

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For purposes of the 2025 Cash Bonus Plan, our compensation committee reserved the discretion to consider the level of achievement of a particular performance goal, or other corporate achievements during 2025 when determining the actual funding level for the plan. This discretion enables our executive officers to focus on the pre-established corporate goals, while also providing flexibility for our executive officers to be nimble in responding to new developments and setbacks, which is necessary for the execution of our business plan.

In December 2025, our compensation committee reviewed performance against the corporate goals. Our compensation committee recognized the effective execution and significant progress made on certain critical business goals, including the advancement of clinical programs and the achievement of internal research goals and those related to our partnered programs; however, our compensation committee also acknowledged the achievement of a positive stockholder return in 2025. Accordingly, our compensation committee recommended and our Board determined that our corporate goals were achieved at 110% of target.

The 2025 bonuses earned by our named executive officers are set forth in "Executive Compensation 2025 Summary Compensation Table" below.

Long-Term Incentive Compensation

Our long-term, equity-based incentive awards are designed to align the interests of our named executive officers with the interests of our stockholders. Because vesting of our equity awards is generally subject to continued service over a period of several years following the date of grant, our equity-based incentives also serve as a retention device for our named executive officers. We generally provide initial equity-based incentive awards in connection with the commencement of employment of our named executive officers as an inducement to commencement of employment. We award annual equity-based incentive awards at or shortly following the end of each year. Awards are subject to vesting over a period of multiple years to provide long-term incentives to deliver sustained stockholder value and to facilitate retention. From time to time, we may also grant awards with performance-based metrics to incentivize and reward targeted corporate goals.

The compensation committee believes that a combination of stock options and RSUs, each with multi-year vesting, provide a balance of incentive and retention and, accordingly, are the most effective compensation strategy for us at this time. The compensation committee views stock options as inherently performance-based compensation that provides a direct link between executive pay and stockholder return, as the value realized, if any, by the executive, is dependent upon, and directly proportionate to, appreciation in stock price over the exercise period and throughout the remaining term prior to exercise. Additionally, stock options will not provide value to the holder if the value of our stock price does not increase after the award is granted. RSUs are a common incentive used by many of our talent competitors, and provide retentive value to executives, particularly during any periods of stock price volatility.

For our 2025 executive long-term incentive mix, the compensation committee determined, in consultation with its compensation consultant, to again include stock options and RSUs.

Typically, we have granted equity-based awards of our common stock to our named executive officers as part of our compensation committee's annual review of executive compensation. To date, our compensation committee has not applied a rigid formula in determining the size of these equity awards. Instead, our compensation committee determines the amount of the equity award for each named executive officer after taking into consideration a compensation analysis performed by its compensation consultant using market data, the equity award recommendations of our Chief Executive Officer (except with respect to his own award), the amount of equity compensation held by the named executive officer (including the current economic value of his or her unvested equity and the ability of these unvested holdings to satisfy our retention objectives), and the factors described in "Compensation-Setting Process" above.

The impact of the Spin-Off on our executive compensation program is described below under "Impact of the 2026 Spin-Off on Named Executive Officers and Executive Compensation Arrangements."

2025 "Refresh" Equity Awards

In January 2025, based upon the considerations and analysis described above, our compensation committee determined to grant options to purchase shares of our common stock and RSUs to our named executive officers in amounts that it considered to be consistent with our compensation philosophy and its desired market positioning and which also recognized

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the performance of each of our named executive officers. The stock options and RSUs granted to our named executive officers in January 2025 were as follows:

2024 Share Price-Based Performance RSUs

In July 2024, after undertaking a comprehensive review and analysis with Compensia, our former independent compensation consultant, our compensation committee determined to grant contingent Performance Stock Units (the "2024 PSUs") to our named executive officers, with each performance stock unit ("PSU") representing a contingent right to receive one share of common stock upon the achievement of $50, $75, and $100 share price, which is approximately a 100%, 200% and 300% price increase above the share price at time of grant. At the time of grant, our 30-day average closing price was $26.29 per share. The 2024 PSUs have the potential to provide meaningful compensation to our executives, but only if they deliver exceptional performance that creates significant returns for the stockholders. The 2024 PSUs were designed to incentivize significant and sustained out performance, with vesting only occurring at stock price targets significantly above our historical stock price and such targets must be satisfied over a 60-trading day average. Moreover, 2024 PSUs were designed to drive our strategic direction and value creation over the long-term by encouraging leadership continuity and collaboration and motivating the executives with equity that rewards them for providing sustained meaningful increases in stockholder value.

The PSUs have a four-year performance period and are divided into three equal tranches, with each tranche eligible to vest based on the achievement, within the performance period, of certain share price targets. If a share price target is achieved, the PSUs allocated to such share price target shall become eligible to vest (the "Eligible PSUs") with (i) 50% of the Eligible PSUs vesting on the one-year anniversary of the later to occur of the date our compensation committee determines achievement of a share price target and July 1, 2025 (such later date the "Service Vesting Commencement Date") and (ii) the remaining 50% of the Eligible PSUs vesting on the two-year anniversary of the Service Vesting Commencement Date. As of December 31, 2025, none of the share price targets were achieved and none of the PSUs were eligible to vest. As of March 2026, the $50 share price target was achieved and the applicable tranche of PSUs was earned and was converted into time-based RSUs vesting such that 50% of such tranche will vest on March 12, 2027 and 50% of such tranche will vest on March 12, 2028.

The impact of the Spin-Off on our executive compensation program, including on our PSUs, is described below under "Impact of the 2026 Spin-Off on Named Executive Officers and Executive Compensation Arrangements."

Welfare and Health Benefits

Our named executive officers participate in our company-sponsored benefit programs on generally the same basis as other salaried employees, including with respect to our 401(k) plan and health and welfare benefits.

Perquisites and Other Personal Benefits

Currently, we do not view perquisites or other personal benefits as a significant component of our executive compensation program. Accordingly, we do not provide significant perquisites or other personal benefits to our named executive officers, except as generally made available to our employees, or in situations where we believe it is appropriate to assist an individual in the performance of his or her duties, to make him or her more efficient and effective, and for recruitment and

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retention purposes. During 2025, none of our named executive officers received perquisites or other personal benefits that were, in the aggregate, $10,000 or more for each individual.

In the future, we may provide perquisites or other personal benefits in limited circumstances, such as those described in the preceding paragraph. All future practices with respect to perquisites or other personal benefits will be approved and subject to periodic review by our compensation committee.

Impact of the 2026 Spin-Off on Named Executive Officers and Executive Compensation Arrangements

On April 20, 2026, we completed the previously announced Spin-Off. The following briefly describes the executive officer transitions and compensatory changes occurring in connection with the Spin-Off.

Spin-Off Named Executive Officer Transitions

Following the Spin-Off, Daniel Faga was our only executive officer. On April 20, 2026, we entered into a consulting agreement with Daniel Faga (the "Faga Consulting Agreement"), pursuant to which Mr. Faga will be engaged as a consultant to serve as Chief Executive Officer of the Company at least through January 15, 2027. Under the Faga Consulting Agreement, we agreed to pay Mr. Faga $100 per month in exchange for such consulting services. Mr. Faga's outstanding equity awards will continue vesting pursuant to their terms during his consultancy, and Mr. Faga remains eligible for accelerated vesting in the event he is terminated prior to January 15, 2027.

On March 26, 2026, we entered into a transition and separation agreement with Dennis Mulroy (the "Mulroy Separation Agreement"), which was effective upon the Spin-Off. The Mulroy Separation Agreement provides that, among other things, the Mulroy Employment Agreement (as defined below) was terminated effective as of the Spin-Off, and in exchange for executing a general release of claims in favor of the Company, Mr. Mulroy received a lump sum payment equal to nine months of base pay and reimbursement for his COBRA premiums for a period of 9 months.

In connection with the Spin-Off, Paul Lizzul's employment as our Chief Medical Officer ceased.

Treatment of Equity in Spin-Off

In connection with the Spin-Off, each of our outstanding equity awards, including the outstanding equity awards held by our NEOs as of the Spin-Off, were treated as follows:

Options. Each outstanding option was converted into (i) an adjusted AnaptysBio option covering the same number of shares and (ii) a new First Tracks Biotherapeutics option covering a number of shares equal to the original share number multiplied by the distribution ratio (which was 1:1). The aggregate exercise price was allocated between the two options based on the respective first closing prices of AnaptysBio common stock and First Tracks Biotherapeutics common stock following the Spin-Off. The new First Tracks Biotherapeutics options were issued under the First Tracks Biotherapeutics 2026 Equity Incentive Plan (the "2026 Plan") on substantially similar terms and conditions as the original AnaptysBio options, including vesting, except that references to AnaptysBio were adjusted to refer to First Tracks Biotherapeutics.

Restricted Stock Units. Each holder of our RSUs received one First Tracks Biotherapeutics RSU for every AnaptysBio RSU and continues to hold the original AnaptysBio RSU in accordance with the applicable award agreement. The First Tracks Biotherapeutics RSUs were issued under the 2026 Plan on substantially similar terms and conditions as the original AnaptysBio RSUs, including vesting, except that references to AnaptysBio were adjusted to refer to First Tracks Biotherapeutics.

Performance Stock Units. Outstanding PSUs that related to the $75 and $100 stock-price hurdles were cancelled and replaced with new PSUs covering shares of First Tracks Biotherapeutics common stock equal in value to the cancelled awards, rounded down to the nearest whole share. The replacement PSUs are subject to substantially equivalent terms and conditions as the cancelled PSUs, except that the stock-price hurdles were equitably adjusted to retain the same ratio relative to the First Tracks Biotherapeutics stock price following the Spin-Off as the original hurdles bore to our stock price prior to the Spin-Off, and performance will be measured based on the First Tracks Biotherapeutics stock price.

Change in Control. If, following the Spin-Off, a change in control of AnaptysBio occurs, all outstanding AnaptysBio equity awards as of the Spin-Off shall accelerate and vest "single-trigger".

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Summary Compensation Table

The following table presents summary information regarding the total compensation that was awarded to, earned by or paid to our named executive officers for services rendered during the years ended December 31, 2025 and 2024.

Outstanding Equity Awards at Fiscal Year-End Table

The following table presents, for each of our named executive officers, information regarding outstanding stock options, RSUs and PSUs held as of December 31, 2025.

This table does not take into account the treatment of outstanding equity awards in 2026 in connection with the Spin-Off. See "Impact of the 2026 Spin-Off on Named Executive Officers and Executive Compensation Arrangements - Treatment of Equity in Spin-Off" above for more information.

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Pay-Versus-Performance

As required by Section 953(a) of the Dodd-Frank Wall Street Reform and Consumer Protection Act and Item 402(v) of Regulation S-K, we are providing the following disclosure regarding executive compensation for our NEOs our total shareholder return and our net income. Those rules require amounts included in the "compensation actually paid" columns of the table to be calculated according to a particular formula intended to demonstrate the relationship between executive compensation actually paid to a company's NEOs and the company's performance. The formula reflects a number of fair value adjustments to equity awards intended to show the change in value of those awards from one year to another. They do not reflect, however, the precise amounts actually earned by or paid to our executives during the years shown in the table.

The compensation committee approves and administers our executive compensation program to align executive compensation with stockholder interests by linking pay to performance. Our overall compensation program includes a mix of short-term and long-term components through our annual incentive plan and equity awards.

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Compensation Actually Paid and Company TSR1

Compensation Actually Paid and Net Income1

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Employment Agreements

The terms and conditions of employment of each of Mr. Faga, Dr. Lizzul and Mr. Mulroy are set forth in written employment agreements. Each of these arrangements was approved by our Board. We believed these employment agreements were necessary to induce these individuals to forego other employment opportunities or leave their current employer for the uncertainty of a demanding position in a new and unfamiliar organization.

Mr. Faga's Employment Agreement

Before the Spin-off, Mr. Faga was party to an employment agreement, effective as of August 3, 2023 (the "Faga Employment Agreement," which amends, restates and supersedes Mr. Faga's previous employment agreement dated March 21, 2022), pursuant to which Mr. Faga served as AnaptysBio's President and Chief Executive Officer until April 20, 2026. The Faga Employment Agreement set forth the principal terms and conditions of his employment as AnaptysBio's President and Chief Executive Officer, including his initial annual base salary and initial annual target cash bonus opportunity, which bonus may be earned based upon the achievement of specified performance goals (and which will be prorated for his partial year of service).

In connection with the Spin-Off and effective April 20, 2026, Mr. Faga is engaged as a consultant to serve as President and Chief Executive Officer of the Company at least through January 15, 2027, pursuant to the Faga Consulting Agreement. Under the Faga Consulting Agreement, we agreed to pay Mr. Faga $100 per month in exchange for such consulting services. Mr. Faga's outstanding equity awards will continue vesting pursuant to their terms during his consultancy, and Mr. Faga remains eligible for accelerated vesting in the event he is terminated prior to January 15, 2027.

Dr. Lizzul's Employment Agreement

Pursuant to an employment agreement effective as of July 31, 2020, as amended and restated on April 25, 2022 (the "Lizzul Employment Agreement"), Dr. Lizzul served as AnaptysBio's Chief Medical Officer. The Lizzul Employment Agreement sets forth the principal terms and conditions of his employment, including his annual base salary, subject to periodic review and an initial annual target cash bonus opportunity, which bonus may be earned based upon the achievement of specified performance goals. Dr. Lizzul's employment was at will and could have been terminated at any time, with or without cause. However, pursuant to the terms of the Lizzul Employment Agreement, Dr. Lizzul would have been entitled to severance benefits upon a qualifying termination of employment as described in "-Potential Payments upon Termination or Change in Control" below. Dr. Lizzul was not entitled to and did not receive severance upon his separation from AnaptysBio.

In connection with the Spin-Off, Dr. Lizzul has ceased to be our Chief Medical Officer, effective as of April 20, 2026.

Mr. Mulroy's Employment Agreement

Pursuant to an employment agreement effective as of July 13, 2020, as amended on April 25, 2022 (the "Mulroy Employment Agreement"), Mr. Mulroy served as our Chief Financial Officer. The Mulroy Employment Agreement set forth the principal terms and conditions of his employment, including his annual base salary, subject to periodic review and an initial annual target cash bonus opportunity, which bonus may be earned based upon the achievement of specified performance goals. Mr. Mulroy's employment was at will and could have been terminated at any time, with or without cause. However, pursuant to the terms of the Mulroy Employment Agreement, Mr. Mulroy would be entitled to severance benefits upon a qualifying termination of employment as described in "-Potential Payments upon Termination or Change in Control" below.

On March 26, 2026, we entered into the Mulroy Separation Agreement, conditioned upon and effective as of the Spin-Off on April 20, 2026. The Mulroy Separation Agreement provides that, among other things, the Mulroy Employment Agreement was terminated, and in exchange for executing a general release of claims in favor of the Company, Mr. Mulroy received a lump sum payment equal to nine months of base pay and reimbursement for his COBRA premiums for a period of nine months.

Mr. Murphy's Employment Agreement

Pursuant to a consulting agreement effective as of May 11, 2026 (the "Murphy Consulting Agreement"), Mr. Murphy serves as our Chief Financial Officer The Murphy Consulting Agreement sets forth the principal terms and conditions of his engagement, including his base consulting fee and an initial annual target cash bonus opportunity, which bonus may be earned based upon the achievement of specified performance goals. Mr. Murphy's consulting role is at will and could be terminated at any time. However, pursuant to the terms of the Murphy Consulting Agreement, Mr. Murphy would be

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entitled to certain benefits upon a termination of his consulting role as described in "-Potential Payments upon Termination or Change in Control" below.

Potential Payments upon Termination or Change in Control

i. Termination

Pursuant to the Faga Employment Agreement, the Lizzul Employment Agreement and the Mulroy Employment Agreement, in the event that, prior to the Spin-Off, Mr. Faga, Dr. Lizzul or Mr. Mulroy was terminated without "cause" or resigns for "good reason" (each as defined in the applicable employment agreement), provided that each delivers a signed settlement and general release in favor of us and satisfies all conditions to make such release effective, (i) in the case of Mr. Faga, he will receive continued severance payments for twelve months, and in the case of Dr. Lizzul and Mr. Mulroy, nine months, (ii) and if each elects continuation coverage under the Consolidated Omnibus Budget Reconciliation Act of 1985 ("COBRA"), we will pay directly to the insurance provider of our group health plans, the monthly premium for such continuation coverage for each officer and his family, for twelve months, in the case of Mr. Faga, and nine months, in the case of Dr. Lizzul and Mr. Mulroy, or such earlier date on which coverage with a new employer is obtained and (iii) in the case of Mr. Faga, 12 months' accelerated vesting of his equity awards (other than the 2024 PSUs, for which only 50% of Eligible PSUs shall vest).

Pursuant to the Murphy Consulting Agreement, in the event that we terminate the Murphy Consulting Agreement without "cause" (and not in connection with a "corporate transaction" as defined in our 2017 Equity Incentive Plan), provided that Mr. Murphy delivers a signed waiver and release of claims in favor of us and satisfies all conditions to make such release effective, Mr. Murphy will receive continued consulting fee payments for nine (9) months following the termination date.

ii. Change in Control

If, following the Spin-Off, a change in control of AnaptysBio occurs, all outstanding AnaptysBio equity awards as of the Spin-Off shall accelerate and vest "single-trigger."

Prior to the Spin-Off and pursuant to the Faga Employment Agreement that was in effect prior to the Spin-Off, if we experienced a change of control prior to the Spin-Off and Mr. Faga was terminated without "cause" or resigns for "good reason" (each as defined in the Faga Employment Agreement) upon the occurrence of, or within 13 months following, such change of control, and provided that Mr. Faga delivers a signed settlement and general release in favor of us and satisfies all conditions to make such release effective, (i) Mr. Faga would receive the continued severance payments and COBRA premiums described above for 18 months, (ii) a bonus payment equal to his target bonus payment for the year, (iii) a prorated bonus based on actual achievement by the Company of goals for the year, and (iv) all of Mr. Faga's outstanding equity awards will vest in full (other than the 2024 PSUs, for which the Board shall determine the number of Eligible PSUs based on the achievement of the share price targets on the date of the change of control and such Eligible PSUs shall fully vest).

Prior to the Spin-Off and pursuant to the Lizzul Employment Agreement and the Mulroy Employment Agreement that were in effect prior to the Spin-Off, if we experienced a change in control prior to the Spin-Off and Dr. Lizzul or Mr. Mulroy, as applicable, was terminated without "cause" or resigns for "good reason" (each as defined in each of the Lizzul Employment Agreement and the Mulroy Employment Agreement) upon the occurrence of, or within 13 months following, such change of control, and provided that Dr. Lizzul or Mr. Mulroy, as applicable, delivers a signed settlement and general release in favor of us and satisfies all conditions to make such release effective, (i) Dr. Lizzul or Mr. Mulroy, as applicable, will receive the severance payments and COBRA premiums described above for 12 months, (ii) Dr. Lizzul's or Mr. Mulroy's, as applicable, currently outstanding equity awards will vest in full (other than the 2024 PSUs, for which the Board shall determine the number of Eligible PSUs based on the achievement of the share price targets on the date of the change of control and such Eligible PSUs shall fully vest) and (iii) Dr. Lizzul or Mr. Mulroy, as applicable, will receive the full payment of his target bonus and a prorated payment of his actual bonus for the applicable year of termination.

Each of the Faga Employment Agreement, the Lizzul Employment Agreement and the Mulroy Employment Agreement contained a "better after-tax" provision, which provides that if any of the payments to Mr. Faga, Dr. Lizzul or Mr. Mulroy, respectively, constitutes a parachute payment under Section 280G of the Code, the payments will either be (i) reduced or (ii) provided in full to the executive, whichever results in the executive receiving the greater amount after taking into consideration the payment of all taxes, including the excise tax under Section 4999 of the Code, in each case based upon the highest marginal rate for the applicable tax.

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If we terminate the Murphy Consulting Agreement without "cause" upon the occurrence of, or within thirteen (13) months following, a "corporate transaction" (as defined in our 2017 Equity Incentive Plan), and provided that Mr. Murphy delivers a signed waiver and release of claims in favor of us and satisfies all conditions to make such release effective, Mr. Murphy will receive (i) continued consulting fee payments for a period of twelve (12) months, (ii) a lump-sum cash amount equal to (a) the Bonus plus (b) an amount equal to the product of (A) his annual bonus, calculated based upon actual achievement of performance goals as determined by the Board, multiplied by (B) the quotient of (x) the number of days elapsed in such fiscal year through the effective date of Mr. Murphy's termination divided by (y) 365, and (iii) all of Mr. Murphy's outstanding equity awards, including the Equity Award, will vest in full.

As noted above in the section entitled "Impact of the 2026 Spin-Off on Executive Officers and Executive Compensation Arrangements-Spin-Off Named Executive Officer Transitions", the employment agreements of our NEOs were terminated at the Spin-Off.

Executive Benefits

Our named executive officers are eligible to participate in our employee benefit plans on the same basis as our other employees, including our health and welfare plans.

Clawback Policy

In September 2023, our Board adopted a clawback policy providing for the recovery of all or any portion of an executive officer's incentive-based compensation in the event that we restate our financial results in compliance with the final rules promulgated by the SEC under Section 954 of the Dodd-Frank Act, Rule 10D-1 and Nasdaq. The policy applies to our Chief Executive Officer, Chief Financial Officer, and other executive officers, including each of our named executive officers. The recovery period extends up to three most recently-completed fiscal years prior to the date of the restatement, with respect to incentive-based compensation granted or received after the effective date of the SEC rules.

Compensation Committee Report

The compensation committee reviewed and discussed the Compensation Discussion and Analysis with management. Based on the review and discussions, the compensation committee recommended to the board of directors that the Compensation Discussion and Analysis be included in our Form 10-K for the fiscal year ended December 31, 2025 and this proxy statement.

Submitted by the Compensation Committee

John Orwin (Chair)

John P. Schmid

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EQUITY PLAN COMPENSATION INFORMATION

The following table presents information as of December 31, 2025 with respect to compensation plans under which shares of our common stock may be issued.

This table does not take into account the treatment of outstanding equity awards in 2026 in connection with the Spin-Off. See "Impact of the 2026 Spin-Off on Named Executive Officers and Executive Compensation Arrangements - Treatment of Equity in Spin-Off" above for more information.

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CERTAIN RELATIONSHIPS AND RELATED-PARTY TRANSACTIONS

From January 1, 2023 to the present, there have been no transactions, and there are currently no proposed transactions, in which the amount involved exceeds the lesser of (i) $120,000 or (ii) 1% of the average of the Company's total assets at year-end for the prior two completed fiscal years and to which we or any of our subsidiaries was (or is to be) a party and in which any director, director nominee, executive officer, holder of more than 5% of our capital stock, or any immediate family member of or person sharing the household with any of these individuals, had (or will have) a direct or indirect material interest, except for payments set forth under "Proposal No. 1 Election of Class III Directors-Non-Employee Director Compensation" and "Executive Compensation" above.

Policies and Procedures for Related Party Transactions

We adopted a written related person transactions policy providing that our executive officers, directors, nominees for election as a director, beneficial owners of more than 5% of our common stock, and any members of the immediate family of and any entity affiliated with any of the foregoing persons, are not permitted to enter into a transaction with us in which the amount involved exceeds (i) $120,000 or (ii) 1% of the average of the Company's total assets at year-end for the prior two completed fiscal years without the review and approval of our audit committee, or a committee composed solely of independent directors in the event it is inappropriate for our audit committee to review such transaction due to a conflict of interest. In approving or rejecting any such proposal, our audit committee will consider the relevant facts and circumstances available and deemed relevant to the audit committee, including, but not limited to, whether the transaction is on terms no less favorable than terms generally available to an unaffiliated third party under the same or similar circumstances and the extent of the related person's interest in the transaction.

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ADDITIONAL INFORMATION

Stockholder Proposals to be Presented at the Next Annual Meeting

Requirements for Stockholder Proposals to be Brought Before an Annual Meeting. Our Bylaws provide that for stockholder nominations to our Board or other proposals to be considered at an annual meeting, the stockholder must give timely notice thereof in writing to the Corporate Secretary at AnaptysBio, Inc., 10770 Wateridge Circle, Suite 210, San Diego, CA 92121.

To be timely for our company's 2027 annual meeting of stockholders, a stockholder's notice must be delivered to or mailed and received by our Corporate Secretary at our principal executive offices not earlier than the close of business on April 28, 2027 and not later than the close of business on May 28, 2027. A stockholder's notice to the Corporate Secretary must set forth as to each matter the stockholder proposes to bring before the annual meeting the information required by applicable law and our Bylaws. In no event will the public announcement of an adjournment or a postponement of our annual meeting commence a new time period for the giving of a stockholder's notice as provided above.

Requirements for Stockholder Proposals to be Considered for Inclusion in our Proxy Materials. Stockholder proposals submitted pursuant to Rule 14a-8 under the Exchange Act and intended to be presented at our 2027 annual meeting of stockholders must be received by us not later than February 22, 2027 in order to be considered for inclusion in our proxy materials for that meeting. A stockholder's notice to the Corporate Secretary must set forth as to each matter the stockholder proposes to bring before the annual meeting the information required by applicable law and our Bylaws.

Available Information

We will mail without charge, upon written request, a copy of our Annual Report on Form 10-K for the year ended December 31, 2025, including the financial statements and list of exhibits, and any exhibit specifically requested. Requests should be sent to:

10770 Wateridge Circle, Suite 210

San Diego, CA 92121

Attn: Corporate Secretary

Our Annual Report on Form 10-K for the year ended December 31, 2025 is also available at http://ir.anaptysbio.com.

"Householding" - Stockholders Sharing the Same Address

The SEC has adopted rules that permit companies and intermediaries (such as brokers) to implement a delivery procedure called "householding." Under this procedure, multiple stockholders who reside at the same address may receive a single copy of our Annual Report on Form 10-K and proxy materials, including the Notice of Internet Availability, unless the affected stockholder has provided other instructions. This procedure reduces printing costs and postage fees and helps protect the environment as well.

We expect that a number of brokers with account holders who are our stockholders will be "householding" our Annual Report on Form 10-K and proxy materials, including the Notice of Internet Availability. A single Notice of Internet Availability and, if applicable, a single set of our Annual Report on Form 10-K and other proxy materials will be delivered to multiple stockholders sharing an address unless contrary instructions have been received from one or more of the affected stockholders. Once you have received notice from your broker that it will be "householding" communications to your address, "householding" will continue until you are notified otherwise or until you revoke your consent. You may revoke your consent at any time by contacting your broker.

Upon written or oral request, we will undertake to promptly deliver a separate copy of the Notice of Internet Availability and, if applicable, our Annual Report on Form 10-K and other proxy materials to any stockholder at a shared address to which a single copy of any of those documents was delivered. To receive a separate copy of the Notice of Internet Availability and, if applicable, Annual Report on Form 10-K and other proxy materials, you may write our Corporate Secretary at 10770 Wateridge Circle, Suite 210, San Diego, CA 92121, or call 1 (858) 362-6348.

Any stockholders who share the same address and currently receive multiple copies of our Notice of Internet Availability or our Annual Report on Form 10-K and other proxy materials who wish to receive only one copy in the future can contact

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their bank, broker or other holder of record to request information about "householding" or our Corporate Secretary at the address or telephone number listed above.

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OTHER MATTERS

Our Board does not presently intend to bring any other business before the meeting and, so far as is known to the Board, no matters are to be brought before the meeting except as specified in the notice of the meeting. As to any business that may arise and properly come before the meeting, however, it is intended that proxies, in the form enclosed, will be voted in respect thereof in accordance with the judgment of the persons voting such proxies.

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ANNEX A

ANAPTYSBIO, INC.

AMENDED AND RESTATED 2017 EQUITY INCENTIVE PLAN

(AS AMENDED AND RESTATED JUNE 17, 2025)

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The Committee may, in recognition of unusual or non-recurring items such as acquisition-related activities or changes in applicable accounting rules, provide for one or more equitable adjustments (based on objective standards) to the Performance Factors to preserve the Committee's original intent regarding the Performance Factors at the time of the initial award grant. It is within the sole discretion of the Committee to make or not make any such equitable adjustments.

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ANNEX B

AMENDMENT NO. 1

TO THE

ANAPTYSBIO, INC.

AMENDED AND RESTATED 2017 EQUITY INCENTIVE PLAN

[___], 2026

This Amendment No. 1 (this "Amendment") to the AnaptysBio, Inc. Amended and Restated 2017 Equity Incentive Plan (the "Plan") was approved and adopted by the Board of Directors (the "Board") of AnaptysBio, Inc. (the "Company") on the date first written above, and will be effective as of the date on which this Amendment is approved by the stockholders of the Company (the "Amendment Effective Date").

WHEREAS, the Company maintains the Plan, and pursuant to Section 24 of the Plan, the Board is authorized to amend the Plan;

WHEREAS, the Board desires to amend the Plan to (i) extend the term of the Plan for ten (10) years from the date this Amendment is approved by the Board and (ii) update the yearly non-employee director compensation limitations; and

WHEREAS, following approval by the Board, this Amendment will become effective as of and contingent upon approval by the Company's stockholders and if, for any reason, the Company's stockholders fail to approve this Amendment, this Amendment shall be void ab initio and the existing Plan shall continue in full force and effect.

NOW, THEREFORE, the Plan is hereby amended as follows, subject to and effective upon the Amendment Effective Date:

"Unless earlier terminated as provided herein, this Plan will terminate ten (10) years from the date this Amendment is approved by the Board."

"12.4. Fiscal Year Compensation Limitation. Commencing from July 1, 2026, no Non-Employee Director may receive Awards under the Plan that, when combined with cash compensation received for service as a Non-Employee Director, exceed $1,000,000 in value (as described below) in the fiscal year of his or her initial service as a Non-Employee Director, or $750,000 in value (as described below) in any subsequent fiscal year. The value of Awards for purposes of complying with this maximum will be determined as follows: (a) for Options and SARs, grant date fair value will be calculated using the Black-Scholes valuation methodology on the date of grant of such Option or SAR; and (b) for all other Awards other than Options and SARs, grant date fair value will be determined by either (i) calculating the product of the Fair Market Value per Share on the date of grant and the aggregate number of Shares subject to the Award, or (ii) calculating the product using an average of the Fair Market Value over a number of trading days as determined by the Board or Committee and the aggregate number of Shares subject to the Award. Awards granted, or cash compensation paid, to an individual while he or she was serving in the capacity as an Employee or while he or she was a Consultant but not a Non-Employee Director will not count for purposes of the limitations set forth in this Section 12.4."

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styleIPCP.O. BOX 8016, CARY, NC 27512-9903 Have your ballot ready and please use one of the methods below for easy voting: Your vote matters! Your control numberHave the 12 digit control number located in the box above available when you access the website and follow the instructions. P.O. BOX 8016, CARY, NC 27512-9903 Have your ballot ready and please use one of the methods below for easy voting: Your vote matters! Your control numberHave the 12 digit control number located in the box above available when you access the website and follow the instructions. Internet: ANAPTYSBIO, INC. Annual Meeting of Stockholders www.proxypush.com/ANAB • Cast your vote online • Have your Proxy Card ready • Follow the simple instructions to record your vote For Stockholders of record as of June 22, 2026 Phone: 1-866-813-1246 Tuesday, August 11, 2026 9:00 AM, Pacific Time • Use any touch-tone telephone 10770 Wateridge Circle, Suite 210 San Diego, California 92121 • Have your Proxy Card ready • Follow the simple recorded instructions Mail: • Mark, sign and date your Proxy Card • Fold and return your Proxy Card in the postage-paid envelope provided YOUR VOTE IS IMPORTANT! PLEASE VOTE BY: 11:59 PM, Eastern Time, August 10, 2026. This proxy is being solicited on behalf of the Board of Directors The undersigned hereby appoints Daniel Faga and Christopher M. Murphy, and each or either of them, as the true and lawful attorneys of the undersigned, with full power of substitution and revocation, and authorizes them, and each of them, to vote all the shares of capital stock of AnaptysBio, Inc. which the undersigned is entitled to vote at said meeting and any adjournment thereof upon the matters specified and upon such other matters as may be properly brought before the meeting or any adjournment thereof, conferring authority upon such true and lawful attorneys to vote in their discretion on such other matters as may properly come before the meeting and revoking any proxy heretofore given. THE SHARES REPRESENTED BY THIS PROXY WILL BE VOTED AS DIRECTED OR, IF NO DIRECTION IS GIVEN, SHARES WILL BE VOTED IDENTICAL TO THE BOARD OF DIRECTORS' RECOMMENDATION. This proxy, when properly executed, will be voted in the manner

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directed herein. In their discretion, the Named Proxies are authorized to vote upon such other matters that may properly come before the meeting or any adjournment or postponement thereof. You are encouraged to specify your choice by marking the appropriate box (SEE REVERSE SIDE) but you need not mark any box if you wish to vote in accordance with the Board of Directors' recommendation. The Named Proxies cannot vote your shares unless you sign (on the reverse side) and return this card. PLEASE BE SURE TO SIGN AND DATE THIS PROXY CARD AND MARK ON THE REVERSE SIDE Copyright © 2026 BetaNXT, Inc. or its affiliates. All Rights Reserved

ANAPTYSBIO, INC. Annual Meeting of Stockholders Please make your marks like this: THE BOARD OF DIRECTORS RECOMMENDS A VOTE: FOR ON PROPOSALS 1, 2, 3 AND 4 BOARD OF DIRECTORS PROPOSAL YOUR VOTE RECOMMENDS 1. To elect two Class III directors, each to serve three-year terms through the third annual meeting of stockholders following this meeting and until a successor has been elected and qualified or until earlier resignation or removal. FOR WITHHOLD 1.01 Hollings Renton FOR #P2# #P2# 1.02 John P. Schmid FOR #P3# #P3# FOR AGAINST ABSTAIN 2. To ratify the appointment of KPMG LLP as our independent registered public accounting firm for FOR #P4# #P4# #P4# the fiscal year ending June 30, 2027. 3. To conduct a non-binding advisory vote on the compensation of our named executive officers as FOR #P5# #P5# #P5# disclosed in the accompanying materials. 4. To approve an amendment to our 2017 Equity Incentive Plan. FOR #P6# #P6# #P6# Authorized Signatures - Must be completed for your instructions to be executed. Please sign exactly as your name(s) appears on your account. If held in joint tenancy, all persons should sign. rustees, administrators, etc., should include title and authority. Corporations should provide full name of corporation and title of authorized officer signing the Proxy/Vote Form. Signature (and Title if applicable) Signature (if held jointly)

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