Table of Contents

PROXY STATEMENT

INFORMATION CONCERNING VOTING AND SOLICITATION

General

Your proxy is solicited on behalf of the board of directors of Adaptive Biotechnologies Corporation (“Adaptive,” the “Company,” “we,” “us” or “our”), a Washington corporation, for use at our 20212024 Annual Meeting of Shareholders (the “Annual Meeting”) to be held on Friday, June 11, 2021,7, 2024, at 9:00 a.m., Pacific Time, or at any continuation, postponement or adjournment thereof, for the purposes discussed in this proxy statement, as well as any business properly brought before the Annual Meeting. Proxies are solicited to give all shareholders of record an opportunity to vote on matters properly presented at the Annual Meeting. The Annual Meeting will be held entirely via the Internet. To be admitted to and participate in the Annual Meeting, you must register prior to Wednesday, June 9, 2021,5, 2024, 2:00 p.m., Pacific Time at www.proxydocs.com/ADPT and enter the control number found on your proxy card, voting instruction form or Notice of Internet Availability of Proxy Materials you previously received. Upon completing your registration, you will receive further instructions via email one hour prior to the start of the Annual Meeting, including your unique link that will allow you access to the Annual Meeting. You will have the ability to submit questions prior to and during the Annual Meeting. Please be sure to follow instructions found on your proxy card and/or Voting Authorization Form and subsequent instructions that will be delivered to you via email.

Technical assistance will be available one hour prior to and during the Annual Meeting. Information related to technical assistance will be provided in the email with the sign-in instructions. We recommend that you log in at least 15 minutes before the Annual Meeting to ensure you are logged in when the Annual Meeting starts. You may vote during the Annual Meeting by following the instructions available on the meeting access email.

We have elected to provide access to our proxy materials over the Internet. Accordingly, on or about April 23, 2021,26, 2024, we are mailing a Notice of Internet Availability of Proxy Materials to most of our shareholders of record and we are mailing paper copies of the proxy materials to certain other shareholders of record. All shareholders will have the ability to access the proxy materials on the website referred to in the notice or request to receive a printed set of the proxy materials. You can find instructions on how to request a printed copy by mail or electronically on the notice and on the website referred to in the notice, including an option to request paper copies on an ongoing basis. On April 23, 2021,26, 2024, we intend to make this proxy statement available on the Internet and to commence mailing of the Notice of Internet Availability of Proxy Materials to all shareholders entitled to vote at the Annual Meeting. We intend to mail this proxy statement, together with a proxy card, to those shareholders entitled to vote at the Annual Meeting who have properly requested paper copies of such materials, within three business days of such request.

Availability of Proxy Materials for the 20212024 Annual Meeting

This proxy statement and our 20202023 Annual Report are available at www.proxydocs.com/ADPT. This website address contains: the Notice of Annual Meeting of Shareholders, the proxy statement and proxy card sample and the 20202023 Annual Report. You are encouraged to access and review all of the important information contained in the proxy materials before voting.

Who Can Vote, Outstanding Shares

Record holders of our common stock as of the close of business on April 14, 2021,10, 2024, the record date for the Annual Meeting (the “Record Date”), are entitled to vote at the Annual Meeting on all matters to be voted upon. As of the Record Date, there were 140,004,251147,368,324 shares of our common stock outstanding. On each matter presented to our shareholders for vote, the holders of common stock are entitled to one vote per share held as of the Record Date.

Voting of Shares

You may vote by attending the Annual Meeting and voting via the Internet, via our toll-free telephone number at 866-390-5390 or by submitting a proxy. The method of voting by proxy differs (1) depending on

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whether you are viewing this proxy statement on the Internet or receiving a paper copy and (2) for shares held as a record holder and shares held in “street name.” If you are a shareholder of record on the Record Date, you can participate in the Annual Meeting online at www.proxypush.com/www.proxydocs.com/ADPT and vote your shares during the Annual Meeting.

Record Holder. If you hold your shares of common stock as a record holder and you are viewing this proxy statement on the Internet, you may vote by submitting a proxy over the Internet by following the instructions on the website

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referred to in the Notice of Internet Availability of Proxy Materials previously mailed to you. If you hold your shares of common stock as a record holder and you are reviewing a paper copy of this proxy statement, you may vote your shares by completing, dating and signing the proxy card that was included with the proxy statement and promptly returning it in the preaddressed, postage-paid envelope provided to you, or by submitting a proxy over the Internet or by telephone by following the instructions on the proxy card.

Hold in Street Name.If you hold your shares of common stock in street name, which means your shares are held of record by a broker, bank or other nominee, you will receive a notice from your broker, bank or other nominee that includes instructions on how to vote your shares. Your broker, bank or other nominee will allow you to deliver your voting instructions over the Internet and may also permit you to vote by telephone. In addition, you may request paper copies of the proxy statement and proxy card from your broker by following the instructions on the notice provided by your broker.

General. If you vote through these facilities, you should be aware that you may incur costs such as usage charges from telephone companies or Internet service providers and that these costs must be borne by you. If you vote through these facilities, then you need not return a written proxy card by mail. The cost of soliciting proxies will be borne by us. We may reimburse banks and brokers and other persons representing beneficial owners for their reasonable out-of-pocket costs. We may use the services of our officers, directors and others to solicit proxies, personally or by telephone, facsimile or electronic mail, without additional compensation.

YOUR VOTE IS VERY IMPORTANT.IMPORTANT. You should submit your proxy even if you plan to attend the Annual Meeting via the Internet. If you are a shareholder of record on the Record Date, you can participate in the Annual Meeting online at www.proxypush.com/www.proxydocs.com/ADPT and vote your shares during the Annual Meeting. If you properly give your proxy and submit it to us in time to vote, one of the individuals named as your proxy will vote your shares as you have directed.

All shares entitled to vote and represented by properly submitted proxies (including those submitted electronically, telephonically and in writing), and not revoked or superseded, will be voted at the Annual Meeting in accordance with the instructions indicated on those proxies. If no direction is indicated on a proxy, your shares will be voted as follows:

The proxy gives each of Chad Robins, Chad CohenKyle Piskel and Stacy Taylor discretionary authority to vote your shares in accordance with their best judgment with respect to all additional matters that might come before the Annual Meeting. If you receive more than one proxy card or Notice of Internet Availability of Proxy Materials, it means you hold shares that are registered in more than one account. To ensure that all of your shares are voted, sign and return each proxy card or, if you submit a proxy by telephone or the Internet, submit one proxy for each proxy card or Notice of Internet Availability of Proxy Materials you receive.

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Revocation of Proxy

If you are a shareholder of record, you may revoke your proxy at any time before your proxy is voted at the Annual Meeting by taking any of the following actions:

Written notices of revocation and other communications with respect to the revocation of Company proxies should be addressed to:

Adaptive Biotechnologies Corporation
1551

1165 Eastlake Avenue East Suite 200

Seattle, WA 98102
98109

Attention: SVP, General Counsel and Corporate Secretary

If your shares are held in “street name,” you may change your vote by submitting new voting instructions to your broker, bank or other nominee. You must contact your broker, bank or other nominee to find out how to do so. See below regarding how to vote live if your shares are held in street name.

Attendance at the Annual Meeting

We are excited to once again hold a virtual-only meeting. Based on our experience in 2020,prior years, this format provides broad shareholder access to our meeting, allowing all shareholders with Internet connectivity to have a consistent experience regardless of location, ability to travel or similar factors.  We have found it also reduces costs forfactors, while saving us and our shareholders time and for us.travel expenses, and, importantly, reducing our environmental impact. We have paid special attention to the meeting platform features, which provide shareholders the opportunity to vote, ask questions and otherwise participate in the meeting in a manner similar to – to—and in some ways superior to –to— traditional in-person shareholder meetings.  While thismeetings, and have found it also reduces costs. The format is particularly useful in light of the continuing COVID-19 pandemic and relatedwhen practical limitations on in-person interaction we believe this format has the potential to facilitate more participationlimit shareholder engagement and shareholder engagement.participation.

If you are the record holder of your shares, you may attend the meeting by registering at the following website: www.proxydocs.com/ADPT. To participate in the Annual Meeting, you will need the control number included on the Notice of Internet Availability of Proxy Materials, your proxy card or the instructions that accompanied your proxy materials. We refer to attending the meeting through this website as attendance “via Internet,” and it is considered the same as attendance in person for all corporate purposes.

If your shares are held in “street name,” in the name of a broker, trustee or other nominee, you may change your vote by submitting new voting instructions to your broker, trustee or other nominee, or, if you have obtained a legal proxy from your broker or other nominee giving you the right to vote your shares, by attending the meeting and voting via the Internet.

Broker Non-Votes

Brokers or other nominees who hold shares of common stock in “street name” for a beneficial owner of those shares typically have the authority to vote in their discretion on “routine” proposals when they have not received instructions from beneficial owners.

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However, brokers are not allowed to exercise their voting discretion with respect to the election of directors or for the approval of other matters that are considered “non-routine” matters without specific voting instructions from the beneficial owner. These non-voted shares are referred to as “broker non-votes.” If your broker holds your common stock in “street name,” your broker will vote your shares on “non-routine” proposals only if you provide instructions on how to vote by filling out the voter instruction form sent to you by your broker with this proxy statement.

Only Proposal No. 43 (ratifying the appointment of our independent registered public accounting firm) is considered a routine matter. Proposals No. 1 (election of directors), and No. 2 (Say-on-Pay) and No. 3 (Say-on-Frequency) are not considered routine matters, and without your instruction, your broker cannot vote your shares for those proposals.

Quorum and Votes Required

The inspector of elections appointed for the Annual Meeting will tabulate votes cast by proxy or live via Internet at the Annual Meeting. The inspector of elections will also determine whether a quorum is present. In order to constitute a quorum for the conduct of business at the Annual Meeting, a majority of the votes entitled to be cast must be represented in person (via Internet) or by proxy at the Annual Meeting. Shares that abstain from voting on any proposal, or that are represented by broker non-votes, will be treated as shares that are present and entitled to vote at the Annual Meeting for purposes of determining whether a quorum is present.

Proposal No. 1: 1: Election of Directors.Directors. A plurality of the votes cast in the election of directors at the Annual Meeting is required for the election of directors. Accordingly, the threetwo Class II director nominees receiving the highest number of

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votes will be elected. Abstentions, “withhold” votes and broker non-votes will have no effect on the outcome of the election of directors. Shareholders are not permitted to cumulate votes with respect to the election of directors.

Proposal No. 2:2: Say-on-Pay Vote. We will consider the advisory approval of the compensation of our named executive officers to have been obtained if the number of votes cast for the proposal at the Annual Meeting exceeds the number of votes against the proposal. Because abstentions and brokernon-votes are neither votes for or against the proposal, they will have no effect on the outcome of the vote. This vote is advisory and not binding on us, our board of directors or our compensation and human capital committee.

Proposal No. 3: Say-on-Frequency Vote. We will consider the advisory approval of the frequency of Say-on-Pay votes to be the frequency alternative (every one year, two years or three years) that receives a number of votes cast for the alternative that exceeds the number of votes cast for the other alternatives.  Because abstentions and brokernon-votes are not votes for any of the alternatives, they will have no effect on the outcome of the vote.  If none of the frequency alternatives receives a majority of the votes cast, the frequency that receives the highest number of votes cast will be deemed to be the frequency recommended by the shareholders.  This vote is advisory and not binding on us, our board of directors or our compensation committee.

Proposal No. 4: 3:Ratification of Independent Registered Public Accounting Firm.Firm. The number of votes for must exceed the number of votes against in order to ratify the selection of Ernst & Young LLP as our independent registered public accounting firm. Abstentions are considered to be votes not cast on this proposal and thus will have no effect. Brokers generally have discretionary authority to vote on the ratification of our independent registered public accounting firm, thus broker non-votes are not expected to result from the vote on Proposal No. 4.3.

In their discretion, the proxy holders named in the proxy are authorized to vote on any other matters that may properly come before the Annual Meeting and at any continuation, postponement or adjournment thereof. The board of directors knows of no other items of business that will be presented for consideration at the Annual Meeting other than those described in this proxy statement. In addition, no shareholder proposal or nomination was received on a timely basis, so no such matters may be brought to a vote at the Annual Meeting.

Solicitation of Proxies

Our board of directors is soliciting proxies for the Annual Meeting from our shareholders. We will bear the entire cost of soliciting proxies from our shareholders. In addition to the solicitation of proxies by delivery of the Notice of Internet Availability of Proxy Materials or proxy statement by mail, we will request that brokers, banks and other nominees that hold shares of our common stock, which are beneficially owned by our shareholders, send Notices of Internet Availability of Proxy Materials, proxies and proxy materials to those beneficial owners

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and secure those beneficial owners’ voting instructions. We will reimburse those record holders for their reasonable expenses. We do not intend to hire a proxy solicitor to assist in the solicitation of proxies. We may use several of our regular employees, who will not be specially compensated, to solicit proxies from our shareholders, either personally or by telephone, Internet, facsimile or special delivery letter.

Communicating with our Board of Directors

Shareholders who wish to communicate with our board of directors or specific individual directors may do so by letter sent to our principal executive offices, addressed to the attention of our Corporate Secretary. Our Corporate Secretary reviews all communications and forwards them to the intended recipient(s) consistent with a screening policy, which provides that sales materials, routine items and items unrelated to the duties and responsibilities of the board of directors are not relayed to directors.

Shareholder Recommendations for Director Nominees

In evaluating potential director nominees, our nominating and corporate governance committee will consider director candidates recommended by our shareholders, provided such recommendations are validly made by the Company’sour shareholders pursuant to Rule 14a-8 under the Securities Exchange Act of 1934 (the “Exchange Act”) and our Bylaws. Shareholders who wish to recommend a candidate to our nominating and corporate governance committee for consideration for nomination should send to us, at our principal executive offices, information regarding the candidate.

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ShareholderShareholder List

A list of shareholders eligible to vote at the Annual Meeting will be available for inspection, for any purpose germane to the Annual Meeting, at our principal executive offices during regular business hours for a period of no less than ten days prior to the Annual Meeting. Information required to gain access to the list of shareholders eligible will also be provided upon request during the same time period.

Forward-Looking Statements

This proxy statement contains “forward-looking statements” (as defined in the Private Securities Litigation Reform Act of 1995). These statements are based on our current expectations and involve risks and uncertainties, which may cause results to differ materially from those set forth in the statements. The forward-looking statements may include statements regarding actions to be taken by us. We undertake no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by law. Forward-looking statements should be evaluated together with the many uncertainties that affect our business, particularly those mentioned in the risk factors in Item 1A of our Annual Report on Form 10-K for the year ended December 31, 2020,2023, and in our periodic reports on Form 10-Q andas well as our current reports on Form 8-K.

CORPORATE GOVERNANCE

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2023 COMPANY HIGHLIGHTS

Selected 2023 Corporate Performance Highlights

Summary of Performance

In 2023, we continued to pursue our business around two main areas: clinical assessment of minimal residual disease (“MRD”) in lymphoid malignancies and immune medicine (“IM”)-driven drug discovery and development.

Our boardrevenue in 2023 was $170.3 million compared to $185.3 million in 2022, with the reduction being accounted for in large part by a decline in the amortization of directors consiststhe upfront payment made in 2019 by our cell therapy partner, Genentech, Inc. (“Genentech”), a slowdown in pharma services largely due to broader macroeconomic factors impacting the biopharmaceutical industry and no MRD milestones.

At the same time, our operating expenses were significantly leveraged as a result of eight members.  Our directors hold office until their successors have been electedcontinued streamlining of our operations during the year. Operating expenses were $397.3 million during 2023, of which $25.4 million represented non-cash impairment charges, as compared to $385.5 million during 2022. As of December 31, 2023, cash, cash equivalents and qualified or untilmarketable securities was $346.4 million. We estimate positive adjusted EBITDA for the earlier of their resignation or removal.  Our Articles of Incorporation and Bylaws provide that our directors may only be removed for cause and then onlyMRD business by the holdersend of 2025, and cash flow breakeven by the shares entitledend of 2026.¹

Selected 2023 Results

MRD Highlights

IM Highlights

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Selected Environmental and the Securities and Exchange Commission (“SEC”).  In making this determination, our board of directors considered the relationships that each non-employee director has with us and all other facts and circumstances that our board of directors deemed relevant, including the beneficial ownership of our common stock by each non-employee director.  The composition and functioning of our board of directors and each of our committees complies with all applicable requirements of Nasdaq and the rules and regulations of the SEC.Social Responsibility Highlights

Family Relationships

Chad Robins, our Chief Executive Officer and Chairman of our board of directors, is the brother of Dr. Harlan Robins, our Chief Scientific Officer.  There are no other family relationships among any of our directors or executive officers.

Staggered Board

In accordance with the terms of our Articles of Incorporation and Bylaws, our board of directors is divided into three staggered classes of directors and each director is assigned to one of the three classes.  At each annual meeting of the shareholders, a class of directors will be elected for a three-year term to succeed the directors of the same class whose terms are then expiring.  The terms of the directors will expire upon the election and qualification of successor directors at the annual meeting of shareholders to be held during the years 2021 for Class II directors, 2022 for Class III directors and 2023 for Class I directors.

Our Articles of Incorporation and Bylaws provide that the number of directors shall be fixed from time to time by a resolution of the majority of our board of directors.

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The division of our board of directors into three classes with staggered three-year terms may delay or prevent shareholder efforts to effect a change of our management or a change in control.

Diversity, Equity and Inclusion

We pride ourselves on inclusive team building, product design and gender diversity at all levels of management, including the board of directors.  We are committed to creating and maintaining a culture of belonging.  In 2020, we expanded and implemented several diversity and inclusion initiatives.  We launched multiple employee resource groups, including Women@Adaptive, Adaptive PRIDE, Black Adapter Network and Working Life and Wellness.  We developed diversity sourcing programs and implemented hiring manager diversity training.  We also established an Equity Advisory Council of senior leaders focused on specific objectives looking at clinical studies, commercial engagement, recruiting and retention through a diversity and inclusion lens.  We also integrated hidden bias training into our Leader of People Program.  Most recently, we launched a STEM minority mentoring program with a local university.  Further, the recent addition of Ms. Trigg and Dr. Owen to the board of directors affirms our commitment to gender diversity at a board level.

Employee Development and Training

We prioritize employee development and training and have established programs to support a culture of employee development. Specifically, in 2020, we offered multiple learning solutions, including our Leader Orientation Program, our Leader of People Program, and our L-re:combinator Program. Our Leader Orientation Program is an eight-week blended learning program that features self-paced online learning and live virtual training, designed to train new line to mid-level leaders about our culture, HR policies, communication, motivation and more. Our Leader of People Program is a three-part, 15-week program designed to train leaders on change management, interviewing and hiring the best talent, having difficult discussions and creating alignment. Our L-re:combinator Program is a peer-to-peer learning group that provides mid-level managers with education, support and collaboration opportunities.  In 2020, over 100 Adapters attended leadership development programs and consumed over 2,000 hours of training.

Environmental Stewardship

We are committed to operating in an environmentally responsible and efficient manner to minimize adverse impacts on the environment.  Asenvironment and have submitted materials relating to our environmental, sustainability and social programs to third party Ecovadis for scoring.

For example, as part of our AdaptiGREEN initiative, we have implemented a variety of composting and recycling programs, including recycling of cardboard, Styrofoam, batteries, Keurig Coffee Pods and sustainable disposition of biohazard waste. Our biohazard waste is destroyed by incineration and the energy generated is captured and used to heat homes on the west coast. Our laboratories reduce energy consumption by utilizing a “night set back” function, which reduces the number of air changes per hour and the flow of ventilation in our fume hoods at night.

With respect to Adaptiveour commuter programs, Adaptive followswe follow the King County Commuter Trip Reduction program; we actively support commuting via bikebicycle and we provide all the amenities required – secure bike storage, onsite self-serve maintenance tools and equipment, and full-service shower rooms. Our all-in-one commuter platform, Luum, enables employees to log their daily commute and obtain “Green Credits” when they commute to work by either bicycle or walking. This credit is in the form of a daily stipend that is paid to eligible employees twice a month and can be used for things like bicycle parts and walking shoes. The Luum platform tracks CO2 avoidance for each employee based on the form of commute transportation they choose each day. We also offer free transit cards (ORCA sound transit) to eligible employees that can be used across multiple public transportation systems. Charging stations for electric carcars and bike charging stationsbikes are also provided in the buildings utilized by Adaptive staff.employees. In addition, a substantial number of our employees work from home either part-or full-time, which presents the opportunity for a reduced carbon footprint.  In connection

We also work with our expansion into a new corporate headquarters at 1165 Eastlake Avenue East, we are collaborating with our landlordlandlords to establishsupport sustainability programs such as those associated with the Green Chemistry Institute, laboratory equipment and electronics recycling. At our headquarters, we operate an urban beekeeping program in association with Alveolé, with rooftop hives to help bolster our commitment to local sustainability. The rooftop of our headquarters also includes gardens maintained by employees in conjunction with our Environmental & Sustainability ERG from which vegetables are sourced for local food insecurity programs.

We also expect our suppliers to operate in an environmentally responsible and efficient manner. Our supplier codeSupplier Code of conductConduct requires suppliers to comply with all applicable environmental regulations; to have systems in place to ensure safe handling, movement, storage, recycling, reuse or management of waste, air emissions and wastewater discharges; and to have systems in place to prevent and mitigate accidental spills and releases of fuels, raw materials, chemicals, intermediates, products and other hazardous materials to the environment.

Clinical Studies / ImmuneCODE

In 2020, in response7

Our People

Our employees, internally referred to the COVID-19 pandemic, we extendedas “Adapters,” are passionate about immune medicine, empowered by scientific discipline and fueled by our collaboration with Microsoftforesight and initiated the ImmuneCODE Program to collect, analyze and publicize datacuriosity about the T cell receptors specific to SARS-CoV-2. We opened our own prospective 1,000 patient study called ImmuneRACE to collect blood samples from people who have been exposed, are actively fighting or have recently recovered from COVID-19 and we are also collecting approximately 4,000 samples from participating institutions around the world that are interested in contributing to this massive effort. Our goal is to leverage the existing capabilities of our high throughput platform to generate an unprecedented amount of T cell data from these patients to understand the adaptive immune responsesystem. As of December 31, 2023, we had 709 full-time employees of which 132 hold medical or doctoral degrees. None of our employees are subject to COVID-19. Importantly,a collective bargaining agreement and we have not experienced any work stoppages. We believe relations with our employees are making these data freely availablegood. For example, we were named the Work Place of the Year by GeekWire in 2023.

Diversity and Inclusion

We pride ourselves on inclusive team building, product design and gender diversity at all levels of management. We are committed to researchers, publiccreating and maintaining a culture of belonging.

Compensation and Benefits

We strive to provide compensation and benefits that are competitive to market and create incentives to attract and retain employees. Our compensation package includes market-competitive base pay, performance-based short-term incentives, health officialscare, retirement benefits, paid time off and organizations aroundfamily leave. In addition, we offer employees the world via an open databenefit of equity ownership in the Company through restricted stock unit awards. We also provide access portalto a variety of health and wellness resources.

Employee Development and Training

We prioritize employee development and training and have established programs to support a culture of employee development. Our Adaptive Leadership Council provides senior employees with the goalaccess to, advance solutions to the pandemic.and a voice in, management decisions.

Product Safety

We are committed to ensuring that our products are manufactured and supplied at high standards of quality. Our manufacturing operations are conducted in compliance with applicable regulatory requirements, Good Clinical Laboratory Practices and our own internal rigorous quality standards. We also require that our suppliers and partners adhere to high standards, and we conduct audits and oversight of our supply chain.

In addition, it is our policy to comply with all applicable drug, medical device, diagnostic, clinical laboratory and research laws and regulations, including Food and Drug Administration (“FDA”) registration, notification, and/or approval, marketing and sales, research and manufacturing requirements, such as Good Laboratory Practices, Good Manufacturing Practices and Good Clinical Practices, as applicable. We also comply with Clinical Laboratory Improvement Amendments of 1988 requirements and related regulations for clinical laboratory testing, where applicable.

BOARD LEADERSHIP STRUCTURE

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CORPORATE GOVERNANCE

Our Board

Our continuing directors and their respective ages (as of April 10, 2024) and class designations are as follows:

Our Criteria for Board Nomination and Service

Our criteria for board membership include specific measures for determining whether a director will be able to devote sufficient time and effort to the role, including consideration of the potential impact of service on other public company boards. This determination is made at the time of nomination and as appropriate during a director’s service on our board if their circumstances change, recognizing that the ability to fully engage in multiple activities will vary depending on the director and the activities.

In that respect, our criteria relating to devotion of time and effort to the Company board include:

In addition, our Bylaws currently address the question of what levels of service on other companies’ boards will be considered permissible for our board directors as follows:

In addition, the nominating and corporate governance guidelines covering, amongcommittee considers individual qualifications, including relevant career experience, strength of character, maturity of judgment and familiarity with our business and industry, as well as all other things,factors it considers appropriate for all board nominations, whether made by shareholders or others.

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The following skills and experiences were considered by the dutiesnominating and responsibilities of and independence standards applicable to our directors and board committee structures and responsibilities.  These guidelines are available on the “Corporate Governance” section of our website at https://investors.adaptivebiotech.com/governance/governance-documents.  Our corporate governance guidelines providecommittee in nominating our non-employee directors:

All board members have global expansion and distribution experience, as well as high level strategic corporate development knowledge.

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While we do not have a formal policy on diversity for members of the board of directors, with flexibility to combinethe nominating and corporate governance committee values and, as reasonable, acts on the need for diversity of director demographics, skills and viewpoints when considering new candidates. The diversity characteristics of our directors are below. None identify as LGBTQ+ or separate the positions of chairpersonas an underrepresented minority; however, future candidates which do so identify and meet our criteria for board service will be considered, as appropriate.

Family Relationships

Chad Robins, our Chief Executive Officer and Chairman of our board of directors, and Chief Executive Officer and to appoint a lead independent director in accordance with its determination that using one or the other structure would be in our best interests.  Chad Robins is the current chairmanbrother of Dr. Harlan Robins, our Chief Scientific Officer. There are no other family relationships among any of our board of directors and Peter Neupert currently serves as the lead independent director of our board of directors.or executive officers.

Board Leadership Structure

Our board of directors has concluded that our current board leadership structure is appropriate for Adaptive’s needs at this time. Our board of directors continues to believe that the combined role of chairperson and Chief Executive Officerchief executive officer promotes united leadership and direction and provides management a clear focus to execute our strategy and business plans. As Chief Executive Officer, Mr. Robins is best suited to ensure that critical business issues are brought before our board of directors, which enhances our board of directors’ ability to develop and implement business strategies.

In his role as lead independent director, Mr. Neupert presides over the independent director sessions of our board of directors in which Mr. Robins, as our Chief Executive Officer, does not participate and serves as a liaison to management on behalf of the non-employee members of our board of directors. Mr. Neupert has been on our board of directors since December 2013, is an independent director who serves on our compensation and human capital committee, audit committee and our nominating and corporate governance committee, has been an executive officer of public companies, and has meaningful experience as an independent director for other public companies. Accordingly, we believe Mr. Neupert provides a strong voice for our independent directors.

All directors are encouraged to suggest the inclusion of agenda items and meeting materials, and any director is free to raise at any board meeting items that are not on the agenda for that meeting.

Our non-employee directors regularly meet in executive sessions without the presence of any members of management. The lead independent director presides at these meetings and provides the guidance and feedback of our non-employee directors to our Chairman and management team.

Our board of directors, as a whole, has responsibility for risk oversight, and each committee of our board of directors oversees and reviews risk in areas that are relevant to it, including: (1) for the compensation and human capital committee, risks associated with the Company’sour compensation arrangements and policies;policies (including, as relevant, matters pertaining to our environmental and social policies and practices); (2) for the nominating and corporate governance committee, periodic review and update of our code of conduct and ethics;ethics as well as corporate governance-specific policies; and (3) for the audit committee, internal controls and regulatory risks related to accounting and finance.finance, as well as periodic review of cybersecurity and privacy risks. The risk oversight responsibility of our board of directors and its committees is supported by our management reporting processes, which are designed to provide visibility to our board of directors and to our personnel who are responsible for risk assessment information about the identification, assessment and management of critical risks.

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Size of Board

Our board of directors consists of six members. Our directors hold office until their successors have been elected and qualified or until the earlier of their resignation or removal. Our Articles of Incorporation and Bylaws provide that our directors may only be removed for cause and then only by the holders of the shares entitled to elect the director or directors whose removal is sought if, with respect to a particular director, the number of votes cast in favor of removing such director (or the entire board of directors) exceeds the number of votes cast against removal, and that any vacancy on our board of directors, including a vacancy resulting from an enlargement of our board of directors, may be filled only by the affirmative vote of a majority of our directors then in office.

Staggered Board and Shareholder Proposals

In accordance with the terms of our Articles of Incorporation and Bylaws, our board of directors is divided into three staggered classes of directors and each director is assigned to one of the three classes. We continue to believe that this board structure is the best choice for Adaptive at this time.

At each annual meeting of the shareholders, a class of directors will be elected for a three-year term to succeed the directors of the same class whose terms are then expiring. The terms of the directors will expire upon the election and qualification of successor directors at the annual meeting of shareholders to be held during the years 2024 for Class II directors, 2025 for Class III directors and 2026 for Class I directors.

Our Articles of Incorporation and Bylaws provide that the number of directors shall be fixed from time to time by a resolution of the majority of our board of directors.

Shareholder proposals may be tendered in the first quarter; however, the division of our board of directors into three classes with staggered three-year terms may delay or prevent shareholder efforts to effect an immediate change of our management or a change in control.

While we have no formal policy with respect to shareholder nominees, the committee will consider recommendations validly made by our shareholders pursuant to Rule 14a-8 under the Exchange Act and our Bylaws.

Board Governance Guidelines

Our board of directors has adopted corporate governance guidelines covering, among other things, the duties and responsibilities of and independence standards applicable to our directors and board committee structures and responsibilities. These guidelines are available on the “Governance” section of our website at https://investors.adaptivebiotech.com/governance/governance-documents.

Our corporate governance guidelines provide our board of directors with flexibility to combine or separate the positions of chairperson of our board of directors and chief executive officer and to appoint a lead independent director in accordance with its determination that using one or the other structure would be in our best interests. Chad Robins is the current chairman of our board of directors and Peter Neupert currently serves as the lead independent director of our board of directors.

Attendance by Members of the Board at Meetings

Our board of directors held sixeight meetings and acted by unanimous written consent sevenfour times during the year ended December 31, 2020.2023. During 2020,2023, all then incumbent directors attended at least 75%all but one of the combined total of (1) all board meetings and (2) all meetings of committees of our board of which the incumbent director was a member. Currently, we do not maintain a formal policy regarding director attendance at the Annual Meeting; however, it is expected that, absent compelling circumstances, each of our directors will attend our Annual Meeting via the Internet. All directors attended the virtual annual meeting in 2020.2023.

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Executive Sessions

Our non-employee directors meet regularly in executive sessions without management to consider such matters as they deem appropriate. Our lead independent director, Mr. Neupert, presides over all executive sessions.

Committees of our Board of Directors

Our board of directors has established an audit committee, a compensation and human capital committee and a nominating and corporate governance committee, each of which operates pursuant to a written charter adopted by our board of directors. Our board of directors may also establish other committees from time to time to assist the board of directors. The composition and functioning of all of our committees comply with all applicable requirements of the Sarbanes-Oxley Act, Nasdaq and SECSecurities and Exchange Commission (“SEC”) rules and regulations, subject to applicable phase-in periods for committees. Each committee has a charter, which is available on our website at www.adaptivebiotech.com.

Independence and Current Committee Positions

Our board of directors has determined that all members of our board of directors, except Chad Robins, are independent directors for purposes of the rules of Nasdaq and the SEC. In making this determination, our board of directors considered the relationships that each non-employee director has with us and all other facts and circumstances that our board of directors deemed relevant, including the beneficial ownership of our common stock by each non-employee director. The composition and functioning of our board of directors and each of our committees complies with all applicable requirements of Nasdaq and the rules and regulations of the SEC.

Audit Committee Service and Responsibilities

During 2020,the first half of 2023, Michelle Griffin, Eric Dobmeier and Michael Pellini, MD and former director Leslie Trigg served on the audit committee, which is currently chaired by Ms. Griffin. David Goel also servedPeter Neupert replaced Ms. Trigg on the audit committee untilafter her resignation from our board in June 2020, and in March 2021, Ms. Trigg replaced Mr. Dobmeier on the audit committee.2023. The audit committee met sevenfive times during fiscal year 2020.2023. Our board of directors has determined that each member of the audit committee during 2023 was and is “independent” as that term is defined in Nasdaq rules and has sufficient knowledge in financial and auditing matters to serve on the audit committee. In addition, our board of directors has determined that Ms. Griffin, Dr. Pellini, and Mr. Neupert each meet (and, during her service, Ms. Trigg and Dr. Pellini each meetmet) the heightened independence requirements for audit committee members required under Section 10A of the Exchange Act and related SEC and Nasdaq rules.  Mr. Dobmeier met these requirements prior to his resignation in March 2021.  For 2020, Mr. Goel did not meet these heightened independence requirements because he may have been deemed to have investment and voting power over the shares of our common stock held by Matrix Fund in his capacity as the sole Managing General Partner of Matrix Capital Management, LP, and we relied, until June 2020, on the phase-in schedules set forth in Rule 10A-3(b)(1)(iv)(A) under the Exchange Act with respect to Mr. Goel’s service on the audit committee, which ended prior to the first anniversary of our initial public offering.  We do not believe such reliance materially adversely affected the ability of the audit committee to act independently and to satisfy the other applicable legal requirements during Mr. Goel’s service.  

Our board of directors has determined that each member of the audit committee is an “audit committee financial expert,” as defined in Item 407(d)(5)(ii) of Regulation S-K. The audit committee’s responsibilities include:

In addition, the audit committee periodically reviews our insider trading policy, which prohibits short sales, pledging, hedging or other monetization transactions, and other transactions which would, if consummated, allow insiders to continue to own our securities without the full risks and rewards of ownership.

Compensation and Human Capital Committee Service and Responsibilities

Until September 2023, Robert Hershberg, PhD, MD, Peter Neupert and former director Kevin Conroy serve on the compensation committee, which has been chaired by Dr. Hershberg since June 2020. Dr. Andris Zoltners served on the compensation and human capital committee, until June 2020.chaired by Dr. Hershberg. Katey Owen replaced Mr. Conroy on the committee after his resignation from our board in September 2023. The compensation committee met fivefour times during fiscal year 2020, and each member attended all meetings.2023. Our board of directors has determined that each member of the compensation and human capital committee during 2023 was and is “independent” as that term is defined in Nasdaq rules and is a “non-employee“non-employee director” under Rule 16b-3 under the Exchange Act. In addition, our board of directors has determined that Dr. Hershberg, Mr. Neupert and Ms. Owen each meet (and, during his service, Mr. Conroy each meetmet) the heightened independence requirements for compensation and human capital committee purposes under Section 10C of the Exchange Act and related SEC and Nasdaq rules. The compensation and human capital committee’s responsibilities include:

The compensation committee, during its first meeting of the year, addresses achievements of the prior year’s corporate goals for purposes of determining annual cash incentive awards.  Following that, most of the significant adjustments to compensation are made to base salary, annual cash incentive and equity awards at the compensation committee’s second meeting of the year, typically held during the first quarter.  Specific issues considered with respect to compensation for fiscal year 2020 included salary, annual cash incentives and equity compensation in light of our second year as a public company and the impact of the COVID-19 pandemic, as well as executive officer compensation in light of

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the products and services developed in response to the pandemic, such as immunoSEQ T-MAP COVID and T-Detect COVID; equity compensation programming, including the development of guidelines to be used for future equity grant cycles, the proper mix of equity vehicles, providing overall pool budgeting and modeling and providing updates with regards to long-term incentive trends among peers; and the non-executive equity compensation program.

The compensation committee also considers at various meetings throughout the year matters related to individual current and future officer compensation, such as compensation for prospective new hires for both our established and emerging lines of business, as well as high-level issues related to compensation strategy, such as efficacy of the current strategy, potential modifications to the strategy, risks created by the strategy, new regulatory requirements and/or the adoption of new trends, and recruitment and retention concerns.  

Nominating and Corporate Governance Committee Service and Responsibilities

Kevin Conroy, Michael Pellini, MD, and Peter Neupert serve on the nominating and corporate governance committee, which has been chaired by Mr. Neupert since June 2020.Neupert. Mr. Conroy also served on the committee until his departure from our board in September 2023. The nominating and corporate governance committee met twiceonce during 2020.2023. Our board of directors has determined that each of Mr. Conroy, Dr. Pellini and Mr. Neupert is (and, during his service, Mr. Conroy was) “independent” as defined in Nasdaq rules.  Mr. Chad Robins, who served as chair of the nominating and corporate governance committee until June 2020, is not “independent” because he is our Chief Executive Officer and we relied on the phase-in schedules set forth in Nasdaq listing rule 5615(b)(1) with respect to Mr. Robins’ historical service on the nominating and corporate governance committee. The nominating and corporate governance committee’s responsibilities include:

The nominating and corporate governance committee will consider director candidates recommended by shareholders on the same basis that it evaluates other nominees for director. Shareholders who wish to recommend a candidate to our nominating and corporate governance committee for consideration for nomination should send to us, at our principal executive offices, information regarding the candidate. In order to identify potential director candidates, the committee may utilize its or our existing networks or retrainretain a third-party recruiting firm.

At a minimum, the nominatingCompensation and corporate governance committee considers individual qualifications, including relevant career experience, strength of character, maturity of judgment and familiarity with our business and industry, in addition to the factors set forth in Appendix A of this proxy statement, as well as all other factors it considers appropriate.  With respect to nominations made directly by shareholders, the committee will consider the factors enumerated above. While we have no formal policy with respect to shareholder nominees, the committee will consider recommendations validly made by our shareholders pursuant to Rule 14a-8 under the Exchange Act and our Bylaws.

While we do not have a formal policy on diversity for members of the board of directors, the nominating and corporate governance committee values the need for diversity of director skills and viewpoints when considering new candidates, as evidenced by the recent recruitment and appointment of Ms. Trigg and Dr. Owen.

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CompensationHuman Capital Committee InterlocksInterlocks and Insider Participation

During 2020,At times as noted above, Kevin Conroy, Robert Hershberg, PhD, MD, Peter Neupert, and Andris Zoltners, PhDKatey Owen served as members of our compensation committee.  Noneand human capital committee during 2023. During 2023, none of the members of our compensation and human capital committee has during the prior fiscal year been one of ourwere officers or employees or except for Dr. Zoltners, had a relationship requiring disclosure under “Relationships“Relationships and Related Party Transactions.Transactions.” None of our executive officers currently serves, nor in the past fiscal year has served, as a member of the board of directors or compensation and human capital committee of any entity that has one or more executive officers serving on our board of directors or compensation and human capital committee.

With respect to Dr. Zoltners, we were historically party to a management services agreement with ZS Associates (“ZS Agreement”), pursuant to which ZS Associates provided us with certain sales and marketing services pursuant to agreed-upon work orders.  We amended and restated the ZS Agreement in 2020.  Dr. Zoltners was one of our directors and a founding director of ZS Associates.  For the fiscal year ended December 31, 2020, we paid ZS Associates $127,000 for services provided under the ZS Agreement.  See “Relationships and Related Party Transactions.”  Dr. Zoltners resigned from our board of directors in October 2020.

CODE OF CONDUCT

We have adopted a written code of business conduct and ethics that applies to our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer or controller or persons performing similar functions. AThe code is updated periodically; a current copy of the code is posted on our website at www.adaptivebiotech.com. IfWhile we make ministerial and technical amendments to the code of conduct and ethics from time to time, if we make any substantive amendments to, or grant any waivers from, the code for any officer or director, we will disclose the nature of such amendment or waiver on our website or in a current report on Form 8-K.

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DIRECTOR COMPENSATION

The following table presents the total compensation for each person who served as a non-employee member of our board of directors at any time during the year ended December 31, 2020.2023. Other than as set forth in the table and described more fully below, we did not pay any compensation, make any additional equity awards or non-equity awards to or pay any other compensation to any of the non-employee members of our board of directors in 2020.2023. We reimburse non-employee members of our board of directors for reasonable travel and out-of-pocket expenses incurred in attending meetings of our board of directors and committees of our board of directors.

We also do not, and do not expect to, provide separate compensation to our directors who are also our employees, such as Chad Robins, our Chief Executive Officer. Mr. Robins’ compensation as our principal executive officer in 20202023 is reported in the “Executive Compensation” section of this proxy statement.

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Our board of directors has adopted a non-employee director compensation policy amended on February 14, 2021, that is designed to enable us to attract and retain, on a long-term basis, highly qualified non-employee directors. Specifically, we provide $50,000provided $60,000 annual cash retainer payments payable quarterly in arrears, to each director who is not an employee of ours, with additional amounts for those serving as Lead Independent Director and chairpersons of our audit, compensation, and nominating and corporate governance committees, as set forth below:

In addition, subject to board discretion, each non-employee director initially elected or appointed to our board of directors will receive a grant of stock options and restricted stock units with a total target economic value equivalent to $400,000, with value determined in accordance with the director compensation policy.comprised 50% of stock options and 50% of RSUs. With respect to the stock option grant, 25% of the shares vest on the first anniversary of the vesting commencement date and 1/48th of the shares vest in monthly installments thereafter, subject to continuous service through each applicable vesting date. With respect to the restricted stock unitRSU grant, 25% of the shares vest on each of the first four anniversaries of the vesting commencement date, subject to continuous service through each applicable vesting date.

On or following the first meeting of our board of directors of each calendar year, each continuingOur non-employee director will also receive a grantcompensation policy sets the total target economic value of the annual director equity grants, comprised 50% of stock options and restricted stock units with a target economic value equivalent to $200,000 with value determined in accordance with the director compensation policy.50% of RSUs, at $250,000. With respect to the stock option grant, 1/12th of the shares vest on each of the first twelve months following the vesting commencement date, subject to continuous service through each applicable vesting date. With respect to the restricted stock unitRSU grant, 100% of the shares vest on the first anniversary of the vesting commencement date, subject to continuous service through each applicable vesting date.

The aggregate amount of compensation under our 2019 Equity Incentive Plan (the “2019 Plan”), including both the grant date fair value of equity compensation and cash compensation, paid to any non-employee director in a calendar year will not exceed $750,000 for the first year of service and $600,000 for each year of service thereafter.

PROPOSAL 1

1:ELECTION OF DIRECTORS

Pursuant to our Articles of Incorporation and our Bylaws, the total number of directors constituting the board of directors is fixed from time to time by the board. The current authorized number of directors is fixed at eight.six. The board of directors is divided into three classes, each containing as nearly as possible an equal number of directors. The current term of office of our Class II directors expires at the Annual Meeting, while the term for our Class III directors will expire at our 20222025 annual meeting of shareholders and the term for our Class I directors expires at our 20232026 annual meeting of shareholders.

Based upon the recommendation of our nominating and corporate governance committee, the board has nominated Michelle Griffin, Peter Neupert and Leslie Trigg, allMichelle Griffin, both current Class II directors, for election at the Annual Meeting. Each director elected at the Annual Meeting will serve a three-year term expiring at our 20242027 annual meeting of shareholders and until his or her successor is duly elected and qualified as a Class II Director,director, or until his or her earlier death, resignation or removal. At the Annual Meeting, proxies cannot be voted for a greater number of individuals than the threetwo nominees named in this proxy statement.

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The board of directors and the nominating and governance committee believe the skills, qualities, attributes and experience of our directors provide us with business acumen and a diverse range of perspectives to engage each other and management to effectively address our evolving needs and represent the best interests of our shareholders.

VacanciesIf any nominee should become unavailable for election prior to the Annual Meeting, an event that currently is not anticipated, the proxies will be voted in favor of the election of a substitute nominee or nominees proposed by the board of directors or the number of directors may be reduced accordingly. Each nominee has agreed to serve if elected and the board of directors has no reason to believe that any nominee will be unable to serve.

We confirm as well that vacancies on the board, including any vacancy created by an increase in the size of the board, may be filled only by a majority of the directors remaining in office, even though less than a quorum of the board, or a sole remaining director. A director elected by the board to fill a vacancy will serve until the next election of the class of directors for which such director was chosen and until such director’s successor is elected and qualified, or until such director’s earlier retirement, resignation, disqualification, removal or death.

If any nominee should become unavailable for election prior to the Annual Meeting, an event that currently is not anticipated, the proxies will be voted in favor of the election of a substitute nominee or nominees proposed by the board of directors or the number of directors may be reduced accordingly.  Each nominee has agreed to serve if elected and the board of directors has no reason to believe that any nominee will be unable to serve.

Our Directors

Our continuing directors and their respective ages (as of April 23, 2021) and class designation are as follows:

Information about Class II Director Nominees Biographies

Set forth below is biographical information for each nominee and a summary of the specific qualifications, attributes, skills and experiences which led our board of directors to conclude that each nominee should serve on the board of directors at this time.  In order to better understand the biographical information set forth below, please note that Adaptive Biotechnologies Corporation was formed in September 2009 and our initial public offering closed in July 2019.

Michelle Griffin has served on our board of directors since March 2019.  Ms. Griffin currently serves on the board of directors of Acer Therapeutics, Inc., a public company, including as chair of the audit committee.  Ms. Griffin also currently serves on the board of directors of HTG Molecular Diagnostics, Inc., a public company, including as chair of the audit committee as well as serves on the board of directors of Chinook Therapeutics, Inc., a public company, including as chair of the audit committee.  Ms. Griffin previously served on the board of directors and as chair of the audit committee of PhaseRx, Inc., formerly a public company, from 2016 to 2018, OncoGenex Pharmaceuticals Inc. (now Achieve Life Sciences, Inc.) from 2008 to 2011 and Sonus Pharmaceuticals, Inc. (now Achieve Life Sciences, Inc.), from 2004 to 2008.  Ms. Griffin served as Executive Vice President, Operations, and Chief Financial Officer at OncoGenex Pharmaceuticals, Inc. from 2011 to 2013, served as Acting Chief Executive, Senior Vice President and Chief Operating Officer at Trubion Pharmaceuticals, Inc. from 2009 until its acquisition in 2010 and as its Chief Financial Officer from 2006 to 2009 and served as Senior Vice President and Chief Financial Officer of Dendreon Corp. from 2005 to 2006.  Ms. Griffin holds a BS in marketing from George Mason University and an MBA from Seattle University.  We believe Ms. Griffin is qualified to serve as a member of our board of directors based on our review of her extensive operational experience in the biotechnology industry and deep experience in public company financial matters.

Peter Neupert has served as a member of our board of directors since December 2013. Mr. Neupert served as an Operating Partner at Health Evolution Partners, a private equity fund, from February 2012 to July 2014. Prior to joining Health Evolution Partners, Mr. Neupert served as Corporate Vice President, Health Solutions Group at Microsoft from August 2005 to January 2012, and as the Chief Executive Officer and Chairman of the board of directors of Drugstore.com, which he foundedjoined in July 1998. Mr. Neupert currently serves on the board of directors of Laboratory Corporation of America Holdings, a public clinical laboratory company, and heFortrea, a clinical research organization. He has previously served as a member of the board of directors of NextGen Healthcare, Inc., a public software company, and several private companies. Mr. Neupert served as a member of the Board of Trustees of Fred Hutchinson Cancer Research Center from June 2007 to June 2020. Mr. Neupert holds an MBA from the Tuck

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School of Business at Dartmouth College and a BA in Philosophy from Colorado College. We believe Mr. Neupert is qualified to serve on our board of directors based on his extensive experience in leadership roles in the health services sector and as a member of the board of directors of several organizations in the biotechnology industry.

Leslie TriggMichelle Griffin has served on our board of directors since March 2019. Ms. Griffin previously served on the boards of directors of Acer Therapeutics, Inc., formerly a public pharmaceutical company, (including as chair of the compensation and human capital committee), HTG Molecular Diagnostics, Inc., formerly a public commercial-stage life sciences company, Chinook Therapeutics, formerly a public clinical-stage biotechnology company, (including as chair of the audit committee), PhaseRx, Inc., formerly a public life sciences company, OncoGenex Pharmaceuticals Inc. (now Achieve Life Sciences, Inc.) and Sonus Pharmaceuticals, Inc. (now Achieve Life Sciences, Inc.). Ms. Griffin also served as Executive Vice President, Operations, and Chief Financial Officer at OncoGenex Pharmaceuticals, Inc. from January 2011 to April 2013, served as Acting Chief Executive, Senior Vice President and Chief Operating Officer at Trubion Pharmaceuticals, Inc. from November 2009 until its acquisition in October 2010 and as its Chief Financial Officer from January 2006 to November 2009; served as Senior Vice President and Chief Financial Officer of Dendreon Corp. from August 2005 to January 2006, and served as Chief Financial Officer of Corixa Corp from October 1997 until its acquisition in August 2005. Ms. Griffin holds a BS in marketing from George Mason University and an MBA from Seattle University. We believe Ms. Griffin is qualified to serve as a member of our board of directors since March 2021.  Ms. Trigg is President and Chief Executive Officer and member of the board of directors of Outset Medical Inc., a medical technology company transforming dialysis care.  Prior to November 2014, Ms. Trigg was an Executive in Residence at Warburg Pincus, a private equity firm, from March 2012 to March 2014. Prior to that, Ms. Trigg served in several roles at Lutonix (acquired by CR Bard), a medical device company, from January 2010 to February 2012, most recently as Executive Vice President, and as Chief Business Officer of AccessClosure (acquired by Cardinal Health), a medical device company, from September 2006 to June 2009. She also previously held positions with FoxHollow Technologies (acquired by ev3/Covidien), a manufacturer of devices to treat peripheral artery disease, Cytyc, a diagnostic and medical device company, Pro-Duct Health (acquired by Cytyc), a medical device company, and Guidant, a cardiovascular medical device company. Ms. Trigg holds a BS from Northwestern University and an MBA from The Haas School of Business, UC Berkeley.  We believe Ms. Trigg is qualified to servebased on our boardreview of directors based on her executive leadershipextensive operational experience in the biotechnology industry includingand deep experience managing sustained revenue and commercial growth in a strategic manner.public company financial matters.

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Board Recommendation

THE BOARD RECOMMENDS A VOTE “FOR” EACH OF THE THREETWO NAMED CLASS II DIRECTOR NOMINEES.

Additional Biographical Information about Other Directors Not Standing for Election at this Meeting

Class III Directors with Terms Expiring at the 20222025 Annual Meeting Biographies

Kevin Conroy has served on our board of directors since April 2019.  Mr. Conroy has served as the President, Chief Executive Officer and Chairman of the board of directors of Exact Sciences Corporation, a public molecular diagnostic company, since March 2009.  Mr. Conroy also serves on the board of directors of Epizyme, Inc., a public clinical-stage biopharmaceutical company, and CM Life Sciences II, Inc., a public special purpose acquisition company sponsored by affiliates of Casdin Capital, LLC and Corvex Management LP.  Prior to joining Exact Sciences Corporation, Mr. Conroy served as President and Chief Executive Officer of Third Wave Technologies, Inc., a molecular diagnostics company, from 2005 to 2008.  From 2019 to 2021, Mr. Conroy served on the board of directors of ARYA Sciences Acquisition Corp., a public special purpose acquisition company sponsored by an affiliate of Perceptive Advisors LLC. Mr. Conroy holds a JD from the University of Michigan Law School and a BS in Electrical Engineering from Michigan State University.  We believe Mr. Conroy is qualified to serve on our board of directors because of his extensive business, legal and executive leadership experience in the biotechnology industry.

Michael Pellini, MD, has served on our board of directors since February 2018.  Dr. Pellini currently serves as a Managing Partner of Section 32, LLC, a technology and life sciences-based venture capital fund.  Dr. Pellini currently serves as a member of the board of directors of the Personalized Medicine Coalition and the Mission Hospital Foundation and several private companies.  Dr. Pellini previously served as Chairman of the board of directors, Chief Executive Officer and President at Foundation Medicine, Inc., a molecular information company, which was acquired by F. Hoffmann-La Roche Ltd. in 2018.  Dr. Pellini holds an MD from Jefferson Medical College, an MBA from Drexel University and a BA in Economics from Boston College.  We believe Dr. Pellini is qualified to serve on our board of directors because of his medical and clinical experience in the biotechnology industry.

Chad Robins co-founded our company in September 2009 and has served as our Chief Executive Officer and a member of our board of directors since incorporation. Mr. Robins currently serves on the board of directors of CM Life Sciences III, Inc., a public special purpose acquisition company sponsored by affiliates of Casdin Capital, LLC and Corvex Management LP. Mr. Robins served on the board of directors of ARYA Sciences Acquisition Corp II, a public special purpose acquisition company, from June 2020 to October 2020. Prior to co-founding our company, Mr. Robins held numerous executive-level positions in medical technology, investment and real estate companies. Mr. Robins holds an MBA from The Wharton School at the University of Pennsylvania and a BS in Managerial Economics from Cornell University. We believe Mr. Robins is qualified to serve as a member of our board of directors based on our review of his experience, qualifications, attributes and skills, including co-founding our company and his executive leadership experience in the biotechnology industry.

19Michael Pellini, MD, has served on our board of directors since February 2018. Dr. Pellini currently serves as a General Partner of Section 32, LLC, a technology and life sciences-based venture capital fund. Dr. Pellini currently serves as a member of the board of directors of the American Cancer Society (a nonprofit organization) and Singular Genomics Systems, Inc. (a public development-stage life sciences company), as well as several private companies. Dr. Pellini previously served as Chairman of the board of directors, Chief Executive Officer and President at Foundation Medicine, Inc., a molecular information company, which was acquired by the Roche Group in 2018. Dr. Pellini holds an MD from Jefferson Medical College, an MBA from Drexel University and a BA in Economics from Boston College. We believe Dr. Pellini is qualified to serve on our board of directors because of his medical and clinical experience in the biotechnology industry.

Class I Directors with Terms ExpiringExpiring at the 20232026 Annual Meeting Biographies

Katey Einterz Owen, PhD, has served as a member of our board of directors since March 2021. Dr. Owen has served as Director, Neglected Tropical Diseases atjoined the Bill &and Melinda Gates Foundation, a private foundation with the goal to enhance healthcare and reduce extreme poverty, since July 2017.  Atin 2013 as Deputy Director of Vaccine Development. In 2017, she stepped into the Bill & Melinda Gates Foundation,role of Director, Neglected Tropical Diseases. In this role, Dr. Owen holds end-to-end responsibilities for a portfolio of investments with the goal to eliminate tropical diseases from the planet. In addition, Dr. Owen joinedassumed the Gates Foundation in 2013 as Deputyposition of Director, for Vaccine Development supporting a portfolio of approximately 100 different vaccines in development.November 2022, with responsibility for target selection, development and commercialization focusing on 100+ vaccine candidates. Prior to joining the Gates Foundation, Dr. Owen held roles of increasing responsibility at Merck & Co., including Executive Director, Merck Vaccines, Sr. Director, Merck Manufacturing Division, and Director, Merck Research Laboratories. Dr. Owen holds a PhD in Molecular Virology and a BS in Genetic Biology from Purdue University. We believe Dr. Owen is qualified to serve on our board of directors based on her extensive scientific expertise and strategic insights into commercialization and manufacturing at scale.

Robert Hershberg, PhD, MD, has served on our board of directors since February 2013. Dr. Hershberg is currently Chairman and CEO of Hillevax, a position he has held since 2020 and has been a Venture Partner at Frazier Healthcare Partners since March 2020. Formerly, from April 2017 to March 2020, Dr. Hershberg was the executive vice president and head of business development and global alliances at Celgene (acquired by Bristol-Myers Squibb in November 2019). He was employed in positions of ascending responsibility at Celgene since joining the company in 2014, including his role as Chief Scientific Officer from January 2016 to March 2020. Dr. Hershberg previously served in several roles at VentiRx Pharmaceuticals, Inc., a clinical stage biopharmaceutical company, which he co-founded in 2006, and was Chief Executive Officer of VentiRx from

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2012 until the company’s acquisition by Celgene in February 2017. Dr. Hershberg currently serves on the board of directors of NanoString Technologies,Fate Therapeutics, Inc., a public company that specializes in the development of cancer diagnostics tools, Silverback Therapeutics, a public biopharmaceutical company specializing in tissue-targeted therapies, andcellular immunotherapies, on the board of directors of Recursion Pharmaceuticals, Inc., a digital biology company.   Dr. Hershberg ispublic company specializing in drug discovery, and as a clinical faculty member at the University of Washington School of Medicine. Dr. Hershberg holds a PhD in Biology from the University of California, San Diego’s Affiliated PhD Program with the Salk Institute for Biological Studies and an MD and a BA from the University of California, Los Angeles. We believe Dr. Hershberg is qualified to serve on our board of directors based on his extensive technical expertise and executive leadership in the biotechnology industry.

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EXECUTIVE OFFICERS

The following table sets forth certain information about our executive officers:

The following is a biographical summary of the experience of our executive officers, with the exception of ChadMr. Robins, whose biographical summary is set forth under the caption “Our “Additional Biographical Information about Other Directors – Class III Directors with Terms ExpiringNot Standing for Election at the 2022 Annual Meeting”this Meeting.”

Julie Rubinstein has served as our President since February 2018.  Prior to becoming our President, Ms. RubinsteinTycho Peterson served as our Chief BusinessFinancial Officer from January 2016June 2022 to February 2018, and our head of Corporate and Business Development from April 2011 to January 2016.2024. Prior to joining us, Ms. RubinsteinMr. Peterson held various worldwide commercial development roles of increasing responsibility at Pfizer Inc.’s Oncology division, primarily focusing on cancer immunotherapy.  She also served in various roles with JohnsonJ.P. Morgan Chase & Johnson Services, Inc., including in Europe.  Ms. Rubinstein currently serves on the Board of Trustees for The Valerie Fund, a pediatric oncology organization in New Jersey and New York.  Ms. Rubinstein holdsCo, an MBAinvestment bank, from Harvard Business School and dual undergraduate degrees from The Wharton School and Annenberg School of Communications at the University of Pennsylvania.

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Harlan Robins, PhD, co-founded our company in September 2009 and has served as either our Chief Scientific Officer or our Head of Innovation since incorporation.  Dr. Robins has served in various roles in the Computational Biology Program at Fred Hutchinson Cancer Research Center, including as an Assistant Faculty Member from 2006May 1999 to 2011, as an Associate from 2011 to April 2016 andJune 2022, most recently serving as a Full Member and the Head of the program from April 2016 to June 2019.  Dr. RobinsManaging Director, Global Equities. Mr. Peterson currently serves on the board of directors of CM Life Sciences III,SomaLogic, Inc., a public special purpose acquisition company sponsored by affiliates of Casdin Capital, LLC and Corvex Management LP.  Dr. Robinsclinical diagnostics company. Mr. Peterson holds a BS in Physics from Harvard Universityan MBA and a master’s degree and PhD in Physicsbiology from the University of California, Berkeley withOxford, and a visiting appointment to the California Institute of Technology.  Dr. Robins received postdoctoral appointmentsBS in the particle theory group at the Weizmann Institute of Science in Israel and at the Institute for Advanced Study at Princetonbiology from Cornell University.  At Princeton, Dr. Robins developed bioinformatics algorithms for micro RNA targets and bacterial genome analysis.

Chad Cohen has servedKyle Piskel succeeded Tycho Peterson as our Chief Financial Officer as of April 8, 2024. He joined us in September 2015 and has served in various roles of increasing levels of responsibility, including as Interim Chief Financial Officer from February 2022 to June 2022 and Principal Accounting Officer since October 2021. Prior to joining us, Mr. Piskel was an Accounting Manager at Expedia Group from October 2014 to August 2015. Prior to joining us,Expedia Group, Mr. Cohen served asPiskel was in the Chief Financial Officer of Zillow Group, Inc.,Assurance services practice at Ernst and Young, LLP from August 2007 to October 2014. Mr. Piskel is a certified public company that operates a real estate marketplace, from March 2011 to August 2015, where he also served as Corporate Controller from June 2006 to March 2011accountant and Vice President of Finance from September 2010 to March 2011.  Prior to joining Zillow, Mr. Cohen served as Assistant Controller and Financial Integrity Manager at Ticketmaster Entertainment, Inc. from 2003 to 2006.  Prior to becoming our Chief Financial Officer, Mr. Cohen served on our board of directors from February 2015 to August 2015.  Mr. Cohen also served on the board of directors of Trupanion, Inc., a public pet insurance company, including as chair of the audit committee, from December 2015 to June 2019.  Mr. Cohen holds a BSBA in Business Administration from Boston University.

Mark Adams, PhD, has served as our Chief Operating Officer since January 2021.  Prior to his appointment as Chief Operating Officer, Dr. Adams served as our Chief Technical Officer from April 2020 to January 2021.  Prior to joining us, Dr. Adams served as Managing Director of SVB Leerink, a health and life-sciences focused investment bank, from April 2018 to March 2020.  Before joining SVB Leerink, from September 2016 to April 2018, he served as Chief Information Officer for Celmatix, Inc., a biotechnology company specializing in reproductive health, and from September 2013 to April 2016, he served as Chief Information Officer for Good Start Genetics, a molecular genetic information company.  His other experience includes work developing unique data warehousing and machine learning approaches and the development of a leading biomedical informatics consulting practice. Dr. Adams holds a B.A. from Oberlin CollegeEastern Washington University and a PhDMaster of Accountancy from Baylor College of Medicine.Gonzaga University.

Lance Baldo, MDSharon Benzeno, PhD, has served as our Chief MedicalCommercial Officer, Immune Medicine since May 2019.  From March 2010 to April 2019, Dr. Baldo served in various roles of ascending responsibility with the Roche Group, a global healthcare company, and its affiliates, including most recently as Senior Vice President and Head of U.S. Medical Affairs of Genentech, Inc.  Prior to joining the Roche Group, Dr. Baldo2022. Before this, she served as Global Vice President, Medical Science and Affairs at The Medicines Company, a public biopharmaceuticals company, from October 2004 to February 2010.  Dr. Baldo holds an MD from the University of Connecticut School of Medicine and a BA in Biology from John Hopkins University.

Francis Lo, has served as our Chief People Officer since May 2019.  Prior to joining us, from March 2017 to April 2019, Mr. Lo served as Vice President, Human Resources at Whole Foods Market, Inc., an operator of natural and organic food supermarkets.  From August 2011 to March 2017, Mr. Lo also served in various roles of ascending responsibility with Starbucks Corporation, a public specialty coffee company, including as Director, Global Talent Management from October 2015 to March 2017.  Mr. Lo holds an MBA in Business Administration from Stanford University Graduate School of Business and a BA in the Plan II Honors Program (Interdisciplinary Studies with Business Focus) from the University of Texas at Austin.

Sharon Benzeno, PhD, has served as our Chief Business Development Officer sincefrom April 2020 and before this, ourto April 2022, Senior Vice President, Drug Discovery sincefrom February 2018 to April 2020 and before that, in business development roles of ascending responsibility with us sincefrom September 2014.2014 to February 2018. Prior to joining us, Dr. Benzeno served as Senior Director at Elsevier Inc., a healthcare informatics company, from December 2013 to September 2014, as Senior Manager in the oncology business unit at Capgemini SE, a French consulting and technology services company, from May 2011 to December 2013, and as Oncology Alliance Manager and Senior Scientific Manager at AstraZeneca plc from September 2005 to May 2011. Dr. Benzeno holds a PhD in Biomedical Sciences from New York University School of Medicine, an MBA in Finance and Leadership from New York University Stern School of Business and a BA in Biochemistry from New York University. Dr. Benzeno completed a postdoctoral fellowship in cancer biology at the University of Pennsylvania Abramson Cancer Center.

Jyoti PalaniappanSusan Bobulskyhas served as our Senior Vice President, Diagnostics, T-Detect (formerly immunoSEQ Dx)Chief Commercial Officer, MRD, since March 2020.January 2024. Before this, she served in commercial and strategic planning roles of ascending responsibility since joining Adaptive in September 2014. Prior to joining us, Mr. Palaniappan served as Chief Commercial Officer for Bigfoot Biomedical, Inc., a medical technology startup specializing in diabetes care, from July 2018 to March 2020.  Prior to Bigfoot, Mr. Palaniappan

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held various worldwide commercial executive roles at Abbott Laboratories, a public global health company, for their Diabetes Care Division from 2007 to 2018.  In addition, he served in various commercial leadership roles at Thermo Fisher Scientific Inc. from 2004 to 2007 and served as a consultant at McKinsey & Company from 2000 to 2004.  He holds an MBA/MPH from Emory University and a BS in Biology from University of Michigan.

Susan Bobulsky has served as Senior Vice President, Diagnostics, clonoSEQ since August 2020.  Prior to this role,Adaptive, Ms. Bobulsky served as our Vice President of clonoSEQ Commercialization from November 2016 to August 2020, as our Vice President of Strategic Planning from April 2016 to October 2016, and as our Senior Director, Market Development from September 2014 to March 2016.  Prior to joining us, Ms. Bobulsky worked inwas an Associate Principal with ZS Associates, a healthcare management consulting firm, where she worked for ZS Associates from September 2010 to September 2014.  Ms. Bobulsky currently serves on the board of directorsnine years specializing in commercialization

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strategy and execution for the Felton Institute, a provider of healthcaretherapeutic and social services, and for the Women’s Cancer Resource Center, a not-for-profit organization focused on addressing inequities in access and delivery of cancer care.diagnostic products. Ms. Bobulsky holds an MBA from the Stanford Graduate School of Business and an undergraduate degreea BS in Science, Technology and Society from Stanford University.

Francis Lo has served as our Chief People Officer since May 2019. Prior to joining us, from March 2017 to April 2019, Mr. Lo served as Vice President, Human Resources at Whole Foods Market, Inc., an operator of natural and organic food supermarkets. From August 2011 to March 2017, Mr. Lo also served in various roles of ascending responsibility with Starbucks Corporation, a public specialty coffee company, including as Director, Global Talent Management from October 2015 to March 2017. Mr. Lo holds an MBA in Business Administration from Stanford University Graduate School of Business and a BA in the Plan II Honors Program (Interdisciplinary Studies with Business Focus) from the University of Texas at Austin.

Harlan Robins, PhD, co-founded our company in September 2009 and has served as either our Chief Scientific Officer or our Head of Innovation since incorporation. Dr. Robins has served in various roles in the Computational Biology Program at Fred Hutchinson Cancer Research Center, including as an Assistant Faculty Member from 2006 to 2011, as an Associate from 2011 to April 2016 and as a Full Member and the Head of the program from April 2016 to June 2019. Dr. Robins currently serves on the board of directors of CM Life Sciences III, Inc., a public special purpose acquisition company sponsored by affiliates of Casdin Capital, LLC. and Corvex Management LP. Dr. Robins holds a BS in Physics from Harvard University and an MS and PhD in Physics from the University of California, Berkeley with a visiting appointment to the California Institute of Technology. Dr. Robins received postdoctoral appointments in the particle theory group at the Weizmann Institute of Science in Israel and at the Institute for Advanced Study at Princeton University. At Princeton, Dr. Robins developed bioinformatics algorithms for micro-RNA targets and bacterial genome analysis.

Julie Rubinstein has served as our President since February 2018 and assumed a strategic operating role as Chief Operating Officer in April 2023. Previously at Adaptive, Ms. Rubinstein served as our Chief Business Officer from January 2016 to February 2018, and our head of Corporate and Business Development from April 2011 to January 2016. Prior to joining us, Ms. Rubinstein held various worldwide commercial development roles at Pfizer Inc.’s Oncology division, primarily focusing on cancer immunotherapy. She also served in various roles with Johnson & Johnson Services, Inc., including in Europe. Ms. Rubinstein currently serves on the Board of Trustees for The Valerie Fund, a pediatric oncology organization in New Jersey and New York. Ms. Rubinstein holds an MBA from Harvard Business School and dual undergraduate degrees from The Wharton School and Annenberg School of Communications at the University of Pennsylvania.

Stacy Taylor has served as our Senior Vice President, and General Counsel since March 2019, and before that, in theour legal department in roles of ascending responsibility with us since March 2018. Prior to joining us, Ms. Taylor served as Senior Associate General Counsel for BTG International plc, a global specialist healthcare company, from July 2017 to March 2018. Prior to joining BTG, Ms. Taylor was a partner at the law firm of DLA Piper LLP (US) from 2007 to 2017, and prior to that practiced intellectual property law in private practice from 1985 to 2007. Ms. Taylor holds a JD from California Western School of Law and a BS in Biological Sciences, Anatomy and Physiology from California Polytechnic State University at San Luis Obispo.

Henning Thorsen has served as our Senior Vice President of Commercial Operations since March 2021.  Prior to joining us, Mr. Thorsen served as Vice President of Commercial Operations for Arrowhead Pharmaceuticals Inc., a public pharmaceutical company, from March 2020 to December 2020, as Vice President of Commercial Operations at Alder Biopharmaceuticals, Inc. a public biopharmaceutical company, from October 2018 to January 2020, as Vice President, Commercial Operations at Juno Therapeutics, a biopharmaceutical company that was acquired by Celgene Corporation in 2018, from January 2017 to July 2018 and as Senior Director, Commercial Operations at Medivation Inc., a biopharmaceutical company, from January 2013 to June 2017. Mr. Thorsen has a BA from the University of California, Santa Barbara.

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