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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

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

Filed by the Registrant ☒
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Filed by a party other than the Registrant  ☐
Check the appropriate box:

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Preliminary Proxy Statement

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Confidential, for Use of the Commission Only (as permitted by Rule14a-6(e)(2))

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Definitive Proxy Statement

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Definitive Additional Materials

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Soliciting Material Under§240.14a-12

§240.14a-12

GRITSTONE ONCOLOGY,BIO, INC.


(Name of Registrant as Specified In Its Charter)

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

Payment of Filing Fee (Check the appropriate box):

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Check box if any part of the fee is offset as provided by Exchange Act Rule0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
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Gritstone Oncology,bio, Inc.

Dear Stockholder:

I am pleased to invite you to attend the 2019virtual 2022 Annual Meeting of Stockholders (the “Annual Meeting”) of Gritstone Oncology,bio, Inc. (“Gritstone”), which will be held online atwww.virtualshareholdermeeting.com/GRTS2019GRTS2022, on June 19, 201917, 2022 at 9:00 a.m. Pacific Time.

The attached Notice of Annual Meeting of Stockholders and Proxy Statement contain details of the business to be conducted at the Annual Meeting.

Whether or not you attend the Annual Meeting, it is important that your shares be represented and voted at the meeting. Therefore, I urge you to promptly vote and submit your proxy via the Internet,internet, by phone or by mail. If you decide to attend the Annual Meeting, you will be able to vote electronically or via phone, using the control number on your proxy card, even if you have previously submitted your proxy.

On behalf of the Board of Directors, I would like to express our appreciation for your interest in Gritstone.

Sincerely,

LOGO


Andrew Allen, M.D., Ph.D.


President and Chief Executive Officer

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GRITSTONE ONCOLOGY,BIO, INC.

5858

5959 Horton Street, Suite 210

300

Emeryville, CA 94608

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON JUNE 19, 2019

To the Stockholders of Gritstone Oncology, Inc.:

NOTICE IS HEREBY GIVEN that the Annual Meeting of Stockholders (the “Annual Meeting”) of Gritstone Oncology, Inc., a Delaware corporation (the “Company”), will be held on June 19, 2019, at 9:00 a.m. Pacific Time. The Annual Meeting will be held entirely online to allow greater participation and improved communication, and provide cost savings for our stockholders and the Company. You will be able to attend and participate in the Annual Meeting online by visitingwww.virtualshareholdermeeting.com/GRTS2019, where you will be able to listen to the meeting live, submit questions and vote. The Annual Meeting will be held for the following purposes:

Time and Date
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June 17, 2022, at 9:00 a.m. Pacific Time
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Place
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The Annual Meeting will be an entirely virtual meeting to be conducted via live webcast at www.virtualshareholdermeeting.com/GRTS2022. To join the Annual Meeting, you will need to have your 16-digit control number included on your Notice of Internet Availability of Proxy Materials and your Proxy Card. The virtual format allows us to increase stockholder access, particularly during a time of continued restrictions on travel and public gatherings, while also saving time and money for both us and our stockholders.
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Items of Business
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To elect two Class I directors to hold office until the 20222025 annual meeting of stockholders or until their successors are elected and qualified;

qualified.

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To ratify the selection, by the audit committee of the Company’s board of directors, of Ernst & Young LLP, as the independent registered public accounting firm of the Company for its fiscal year ending December 31, 2019; and

2022.

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To transact such other business as may properly come before the Annual Meeting or any adjournment or postponement thereof.

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Record Date
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Only stockholders who owned common stock of the Company at the close of business on April 20, 2022 (the “Record Date”) are entitled to receive notice of and vote at the Annual Meeting or any adjournments that take place.
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Board of Directors Recommendations
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The board of directors of the Company (the “Board of Directors”) recommends that you vote:
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FOR the election of the director nominees named in Proposal No. 1 of the Proxy Statement; and
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FOR the ratification of the appointment of Ernst & Young LLP, as the independent registered public accounting firm, as described in Proposal No. 2 of the Proxy Statement.

The foregoing items of business are more fully described in the Proxy Statement accompanying this Notice of Annual Meeting of Stockholders. Only stockholders who owned common stock of the Company at the close of business on April 22, 2019 (the “Record Date”) can vote at this meeting or any adjournments that take place.

The board of directors recommends that you vote:

FOR the election of the director nominees named in Proposal No. 1 of the Proxy Statement; and

FOR the ratification of the appointment of Ernst & Young LLP, as the independent registered public accounting firm, as described in Proposal No. 2 of the Proxy Statement.

YOUR VOTE IS IMPORTANT. WHETHER OR NOT YOU PLAN TO ATTEND THE ANNUAL MEETING ONLINE, WE ENCOURAGE YOU TO READ THE ACCOMPANYING PROXY STATEMENT AND OUR ANNUAL REPORT ON FORM10-K FOR THE YEAR ENDED DECEMBER 31, 2018,2021, AND SUBMIT YOUR PROXY AS SOON AS POSSIBLE USING ONE OF THE THREE CONVENIENT VOTING METHODS DESCRIBED IN THE “INFORMATION ABOUT THE PROXY PROCESS AND VOTING” SECTION IN THE PROXY STATEMENT. IF YOU RECEIVE MORE THAN ONE SET OF PROXY MATERIALS OR NOTICE OF INTERNET AVAILABILITY BECAUSE YOUR SHARES ARE REGISTERED IN DIFFERENT NAMES OR ADDRESSES, EACH PROXY SHOULD BE SIGNED AND SUBMITTED TO ENSURE THAT ALL OF YOUR SHARES WILL BE VOTED.

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By Order of the Board of Directors

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/s/ Andrew Allen

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Andrew Allen, M.D., Ph.D.


President and Chief Executive Officer

Emeryville, California


April 26, 2019

28, 2022

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PROXY STATEMENT FOR THE 20192022 ANNUAL MEETING OF STOCKHOLDERS TO BE HELD ON JUNE 19, 201917, 2022

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INFORMATIONQUESTIONS AND ANSWERS ABOUT THE ANNUAL MEETING, THE PROXY PROCESS AND VOTING

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PROPOSAL NO. 1 ELECTION OF DIRECTORS

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PROPOSAL NO. 2 RATIFICATION OF SELECTION OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

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REPORT OF THE AUDIT COMMITTEE OF THE BOARD OF DIRECTORS

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CORPORATE GOVERNANCE

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Code of Business Conduct and Ethics

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Corporate Governance Guidelines

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Independence of the Board of Directors

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Leadership Structure of the Board

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Role of Board in Risk Oversight Process

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Board Committees

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Board Diversity

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Meetings of the Board of Directors, Board and Committee Member Attendance and Annual Meeting Attendance

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Stockholder Communications with the Board of Directors

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Compensation Committee Interlocks and Insider Participation

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Derivatives Trading, Hedging, and Pledging Policies
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CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS

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EXECUTIVE OFFICERS

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EXECUTIVE COMPENSATION

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Summary Compensation Table

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Outstanding Equity Awards at 20182021 Fiscal Year End

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Narrative to Summary Compensation Table and Outstanding Equity Awards at 20182021 Fiscal Year End

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Equity Compensation Plan Information

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DIRECTOR COMPENSATION

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

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SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

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ADDITIONAL INFORMATION

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Householding of Proxy Materials

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Incorporation by Reference
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Other Matters

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GRITSTONE ONCOLOGY,BIO, INC.

5858

5959 Horton Street, Suite 210

300

Emeryville, CA 94608



PROXY STATEMENT



FOR THE 20192022 ANNUAL MEETING OF STOCKHOLDERS



IMPORTANT NOTICE REGARDING THE INTERNET AVAILABILITY OF PROXY MATERIALS FOR THE STOCKHOLDER MEETING TO BE HELD ON



JUNE 19, 2019

17, 2022

We have sent you this Proxy Statement and the enclosed proxy card (“Proxy CardCard”) because the board of directors (the “Board of Directors”) of Gritstone Oncology,bio, Inc. (referred to herein as the “Company,” “Gritstone,” “we,” “us” or “our”) is soliciting your proxy to vote at our 2019 annual meeting2022 Annual Meeting of stockholders (the “Annual Meeting”) to be held on Wednesday,Friday, June 19, 2019,17, 2022, at 9:00 a.m. Pacific Time. The Annual Meeting can be accessed by visiting www.virtualshareholdermeeting.com/GRTS2019,GRTS2022, where you will be able to listen to the meeting live, submit questions and vote online.

This Proxy Statement summarizes information about the proposals to be considered at the Annual Meeting and other information you may find useful in determining how to vote.

The Proxy Card is the means by which you actually authorize another person to vote your shares in accordance with your instructions.

In addition to solicitations by mail, our directors, officers and regular employees, without additional remuneration, may solicit proxies by telephone,e-mail and personal interviews. We may retain outside consultants to solicit proxies on our behalf as well. All costs of solicitation of proxies will be borne by us. Brokers, custodians and fiduciaries will be requested to forward proxy soliciting material to the owners of stock held in their names, and we will reimburse them for their reasonableout-of-pocket expenses incurred in connection with the distribution of proxy materials.

Pursuant to the rules adopted by the Securities and Exchange Commission (the “SEC”), we have elected to provide access to our Annual Meeting materials, which include this Proxy Statement and our Annual Report on Form10-K for the year ended December 31, 20182021 (the “Form10-K”), over the internet in lieu of mailing printed copies. We will begin mailing the Notice of Internet Availability to our stockholders of record as of the close of business on April 22, 201920, 2022 (the “Record Date”) for the first time on or about May 3, 2019.April 28, 2022. The Notice of Internet Availability will contain instructions on how to access and review the Annual Meeting materials and will also contain instructions on how to request a printed copy of the Annual Meeting materials. In addition, we have provided brokers, dealers, banks, voting trustees and their nominees, at our expense, with additional copies of our proxy materials and the Form10-K so that our record holders can supply these materials to the beneficial owners of shares of our common stock as of the Record Date. The Form10-K is also available in the “Investors & Media – SEC Filings” section of our website at http://www.gritstoneoncology.com.

www.gritstonebio.com.

The only outstanding voting securities of Gritstone are shares of common stock, $0.0001 par value per share (the “common stock”), of which there were 29,206,40572,812,833 shares outstanding as of the Record Date (excluding any treasury shares). The holders of a majority in voting power of the shares of common stock issued and outstanding and entitled to vote, present in attendance online or represented by proxy, are required to hold the Annual Meeting.

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QUESTIONS AND ANSWERS ABOUT THE ANNUAL MEETING, THE PROXY PROCESS AND VOTING

The information provided in the “question and answer” format below addresses certain frequently asked questions but is not intended to be a summary of all matters contained in this Proxy Statement. Please read the entire Proxy Statement carefully before voting your shares.
Why am I receiving these materials?

We have made this Proxy Statement and Proxy Card available to you on the internet or, upon your request, have delivered printed proxy materials to you, because the boardBoard of directorsDirectors is soliciting your proxy to vote at the Annual Meeting, including at any adjournments or postponements of the Annual Meeting. You are invited to attend the Annual Meeting online to vote on the proposals described in this Proxy Statement. However, you are not required to attend the Annual Meeting to vote your shares. Instead, you may simply complete, sign and return the Proxy Card, or follow the instructions below to submit your proxy over the telephone or on the internet.

This Proxy Statement, the Notice of Internet Availability, the Notice of Annual Meeting and accompanying Proxy Card were first made available for access, by our stockholders on or about April 26, 201928, 2022, to all stockholders of record entitled to vote atas of the Annual Meeting.

Record Date.

Who can vote at the Annual Meeting?

Only stockholders

Holders of recordour common stock at the close of business on April 20, 2022, the Record Date will befor the Annual Meeting, are entitled to notice of and to vote at the Annual Meeting. Each stockholder of record is entitled to one vote for each share of our common stock held as of the Record Date. At the close of business on the Record Date, there were 29,206,40572,812,833 shares of common stock issued and outstanding and entitled to vote.

Stockholder of Record: Shares Registered in Your Name

If, on the Record Date, your shares were registered directly in your name with the transfer agent for our common stock, American Stock Transfer & Trust Company, LLC, then you are a stockholder of record. As a stockholder of record, you may vote at the Annual Meeting by attending the Annual Meeting online and following the instructions posted atwww.virtualshareholdermeeting.com/GRTS2019GRTS2022 or you may vote by proxy. Whether or not you plan to attend the Annual Meeting online, we encourage you to fill out and return the Proxy Card or vote by proxy over the telephone or on the internet as instructed below to ensure your vote is counted.

Beneficial Owner: Shares Registered in the Name of a Broker, Bank or Other Agent

If, on the Record Date, your shares were held in an account at a brokerage firm, bank, dealer or other similar organization, then you are the beneficial owner of shares held in “street name” and these proxy materials are being forwarded to you by that organization. The organization holding your account is considered the stockholder of record for purposes of voting at the Annual Meeting. As a beneficial owner, you have the right to direct your broker or other agent on how to vote the shares in your account. You are also invited to attend the Annual Meeting online at www.virtualshareholdermeeting.com/GRTS2019.GRTS2022. However, since you are not the stockholder of record, you may not vote your shares at the Annual Meeting by attending the Annual Meeting online unless you request and obtain a valid Proxy Card from your broker or other agent.

What am I being asked to vote on?

You are being asked to vote on two proposals:

Proposal 1—the election of two Class I directors to hold office until our 20222025 annual meeting of stockholders; and

Proposal 2—the ratification of the selection, by the audit committee of our board of directors, of Ernst & Young LLP, as our independent registered public accounting firm for the year ending December 31, 2019.

2022.

In addition, you are entitled to vote on any other matters that are properly brought before the Annual Meeting.

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How do I attend the Virtual Annual Meeting?

This year’s Annual Meeting will be held entirely online to allow greater participation and improved communication and provide cost savings for our stockholders and the Company. Stockholders of record as of the close of business on April 22, 201920, 2022 will be able to attend and participate in the Annual Meeting online by accessing www.virtualshareholdermeeting.com/GRTS2019.GRTS2022. To join the Annual Meeting, you will need to have your16-digit control number which is included on your Notice of Internet Availability of Proxy Materials and your proxy card.

Even if you plan to attend the Annual Meeting online, we recommend that you also vote by proxy as described herein so that your vote will be counted if you decide not to attend the Annual Meeting.

Could developments regarding COVID-19 impact the date, time or location of the meeting?
We are actively monitoring the public health and travel safety concerns relating to COVID-19 and the advisories or mandates that federal, state and local governments, and related agencies, may issue. Our Annual Meeting is a completely virtual meeting of stockholders, to be conducted via live webcast in order to accommodate social distancing of those attending the meeting, and as such we do not anticipate an impact to the date, time or location of our Annual Meeting. If we determine that it is not possible or advisable to hold our Annual Meeting as currently planned, we will announce by press release as well as through a filing with the SEC.
How do I vote?

For Proposal 1, you may either vote “For” or “Withhold” your vote from any of the nominees of the board of directors.

For Proposal 2, you may either vote “For” or “Against” or abstain from voting.

Please note that by casting your vote by proxy you are authorizing the individuals listed on the Proxy Card to vote your shares in accordance with your instructions and in their discretion with respect to any other matter that properly comes before the Annual Meeting or any adjournments or postponements thereof.

The procedures for voting are as follows:

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you may vote at the Annual Meeting. Alternatively, you may vote by proxy by using the accompanying Proxy Card, over the internet or by telephone. Whether or not you plan to attend the Annual Meeting online, we encourage you to vote by proxy to ensure your vote is counted. Even if you have submitted a proxy before the Annual Meeting, you may still attend the Annual Meeting and vote online. In such case, your previously submitted proxy will be disregarded.

You may vote via the Annual Meeting Website. To vote at the Annual Meeting, attend the Annual Meeting online and follow the instructions posted at www.virtualshareholdermeeting.com/GRTS2019.

GRTS2022.

You may vote by mail. To vote by mail using the Proxy Card, simply complete, sign and date the accompanying Proxy Card and return it promptly in the envelope provided.provided so that it is received no later than June 16, 2022 (or, if applicable, an earlier date indicated on the Proxy Card). If you return your signed Proxy Card before the Annual Meeting,as instructed, we will vote your shares in accordance with the Proxy Card.

You may vote via the Internet. To vote by proxy over the internet, follow the instructions provided on the Notice of Internet Availability.

Your vote must be received by 11:59 p.m. Eastern Time on June 16, 2022 to be counted.

You may vote by telephone. To vote by telephone, you may vote by proxy by calling the toll freetoll-free number found on the Notice of Internet Availability.

Proxy Card. Your vote must be received by 11:59 p.m. Eastern Time on June 16, 2022 to be counted.

Beneficial Owner: Shares Registered in the Name of Broker, Bank or Other Agent

If you are a beneficial owner of shares registered in the name of your broker, bank or other agent, you should have received a voting instruction card and voting instructions with these proxy materials from that organization
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rather than from us. Simply complete and mail the voting instruction card to ensure that your vote is counted. To vote at the Annual Meeting, you must obtain a valid proxy from your broker, bank or other agent. Follow the instructions from your broker, bank or other agent included with these proxy materials, or contact your broker, bank or other agent to request a proxy form.

We provide internet proxy voting to allow you to vote your shares online before the Annual Meeting takes place, with procedures designed to ensure the authenticity and correctness of your proxy vote instructions. However, please be aware that you must bear any costs associated with your internet access, such as usage charges from internet access providers and telephone companies.

Who counts the votes?

We have engaged Broadridge Financial Solutions, Inc. (“Broadridge”) as our independent agent to tabulate stockholder votes or Inspector(the “Inspector of Election.Election”). If you are a stockholder of record, your executed Proxy Card is returned directly to Broadridge for tabulation. As noted above, if you hold your shares through a broker, your broker returns one Proxy Card to Broadridge on behalf of all its clients.

How are votes counted?

With respect to the election of directors (Proposal 1), you may vote “for” or “withhold” authority to vote for each of the nominees for the boardBoard of directors.Directors. If you “withhold” authority to vote with respect to one or more director nominees, your vote will have no effect on the election of such nominees. Brokernon-votes will have no effect on the election of the nominees.

With respect to the ratification of Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 20192022 (Proposal 2), you may vote “for,” “against” or “abstain.” If you “abstain” from voting with respect to this proposal, your vote will have the same effect as a vote “against” the proposal. BrokerAs explained below, broker non-votes will have no effect on the vote for this proposal.

Votes will be counted by the Inspector of Election appointed for the Annual Meeting, who will separately count “For” and, with respect to Proposal 2, “Against” votes, abstentions and brokernon-votes. If your shares are held by your broker as your nominee (that is, in “street name”), you will need to obtain a proxy form from the institution that holds your shares and follow the instructions included on that form regarding how to instruct your broker to vote your shares. If you do not give instructions to your broker, your broker can vote your shares with respect to “routine” items, but not with respect to“non-routine” “non-routine” items. See below for more information regarding: “What are “brokernon-votes”?”and “Which ballot measures are considered “routine” or“non-routine” “non-routine”?”

What are “brokernon-votes”?

Brokernon-votes occur when a beneficial owner of shares held in “street name” does not give instructions to the broker or nominee holding the shares as to how to vote on matters deemed“non-routine. “non-routine.” Generally, if shares are held in street name, the beneficial owner of the shares is entitled to give voting instructions to the broker or nominee holding the shares. If the beneficial owner does not provide voting instructions, the broker or nominee can still vote the shares with respect to matters that are considered to be “routine,” but not with respect to“non-routine” “non-routine” matters. In the event that a broker, bank, custodian, nominee or other record holder of common stock indicates on a proxy that it does not have discretionary authority to vote certain shares on a particular proposal, then those shares will be treated as brokernon-votes with respect to that proposal. Accordingly, if you own shares through a nominee, such as a broker or bank, please be sure to instruct your nominee how to vote to ensure that your vote is counted on each of the proposals.

Which ballot measures are considered “routine” or“non-routine?”

“non-routine”?

The ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 20192022 (Proposal 2), is considered routine under applicable rules. A broker or other nominee may generally vote on routine matters, and therefore no brokernon-votes are expected to exist

in connection with Proposal 2. The election of directors (Proposal 1) is considerednon-routine under applicable rules. A broker or other nominee cannot vote without instructions onnon-routine matters, and therefore there may be brokernon-votes on Proposal 1.

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How many votes are needed to approve the proposal?

Election of Directors (Proposal 1)—Directors shall be elected by a plurality of the votes cast (meaning that the two director nominees who receive the highest number of shares voted “For” their election are elected). “Withhold” votes and brokernon-votes are not considered votes cast for the foregoing purpose and will have no effect on the election of the nominees.

Ratification of Independent Registered Public Accounting Firm (Proposal 2)—The ratification of Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 20192022 requires the affirmative vote of the majority of the votes cast (meaning the number of shares voted “for” the proposal must exceed the number of shares voted “against” the proposal). Abstentions and brokernon-votes are not considered votes cast for the foregoing purpose and will have no effect on the vote for this proposal.

How many votes do I have?

On each matter to be voted upon, you have one vote for each share of common stock you own as of the Record Date.

What if I return a Proxy Card but do not make specific choices?

If we receive a signed and dated Proxy Card and the Proxy Card does not specify how your shares are to be voted, your shares will be voted “For” the election of each of the two nominees for director, and “For” the ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm. If any other matter is properly presented at the Annual Meeting, your proxy (one of the individuals named on your Proxy Card) will vote your shares in his or her discretion.

Who is paying for this proxy solicitation?

We will pay for the entire cost of soliciting proxies. In addition to these mailed proxy materials, our directors, officers and employees may also solicit proxies in person, by telephone or by other means of communication. Directors, officers and employees will not be paid any additional compensation for soliciting proxies. We may also reimburse brokerage firms, banks and other agents for the cost of forwarding proxy materials to beneficial owners.

What does it mean if I receive more than one set of materials?

If you receive more than one set of materials, your shares are registered in more than one name or are registered in different accounts. In order to vote all the shares you own, you must either sign and return all of the Proxy Cards or follow the instructions for any alternative voting procedure on each of the Proxy Cards.

Can I change my vote after submitting my proxy?

Yes. You can revoke your proxy at any time before the final vote at the Annual Meeting. If you are the record holder of your shares, you may revoke your proxy in any one of three ways:

You may submit another properly completed proxy,Proxy Card, bearing a date later than the date of the original proxy.

Proxy Card.

You may senddeliver a written notice, bearing a date later than the date of the original proxy,Proxy Card, that you are revoking your proxy to our Corporate Secretary at 58585959 Horton Street, Suite 210,300, Emeryville, CA 94608.

94608 by 11:59 p.m. Eastern Time on June 16, 2022.

You may attend the Annual Meeting online and vote by following the instructions at www.virtualshareholdermeeting.com/GRTS2019.GRTS2022. Simply attending the Annual Meeting online will not, by itself, revoke your proxy.

If your shares are held in “street name” by your broker, bank or other agent, you should follow the instructions provided by them to change your vote.

When are stockholder proposals due for next year’s Annual Meeting?

To be considered for inclusion in next year’s proxy materials, your proposal must be submitted in writing by December 28, 2019,29, 2022, to our Corporate Secretary at our principal executive offices; provided that, if the date of the annual meeting is more than 30 days from June 19, 2020,17, 2023, the deadline is a reasonable time before we begin to
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print and send our proxy materials for next year’s annual meeting. Pursuant to theour bylaws, in order for a stockholder to present a proposal for next year’s annual meeting, other than proposals to be included in the proxy statement as described above, or to nominate a director, you must do so between February 19, 202017, 2023 and March 21, 2020;29, 2023; provided that if the date of that annual meeting is more than 30 days before or more than 60 days after June 19, 2020,17, 2023, you must give notice not later than the 90th90th day prior to the annual meeting date or, if later, the 10th10th day following the day on which public disclosure of the annual meeting date is first made. You are also advised to review our bylaws, which contain additional requirements about advance notice of stockholder proposals and director nominations.

In addition to satisfying the foregoing requirements under our bylaws, to comply with the SEC’s universal proxy rules (once they become effective), stockholders who wish to solicit proxies in support of director nominees other than our proposed nominees must provide a notice that sets forth the information required by Rule 14a-19 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), no later than April 18, 2023.
What is the quorum requirement?

A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if the holders of a majority in voting power of the shares of common stock issued and outstanding and entitled to vote are present in attendance online or represented by proxy at the Annual Meeting. On the Record Date, there were 29,206,40572,812,833 shares outstanding and entitled to vote. Accordingly, 14,603,20336,406,417 shares must be represented by stockholders present at the Annual Meeting online or by proxy to have a quorum.

Your shares will be counted toward the quorum only if you submit a valid proxy or vote at the Annual Meeting. Abstentions and “Withhold” votes will be counted toward the quorum requirement. If there is no quorum, either the chair of the Annual Meeting or a majority in voting power of the stockholders entitled to vote at the Annual Meeting, in attendance online or represented by proxy, may adjourn the Annual Meeting to another time or place.

How can I find out the results of the voting at the Annual Meeting?

Voting results will be announced by the filing of a Current Report on Form8-K within four (4) business days after the Annual Meeting. If final voting results are unavailable at that time, we will file an amended Current Report on Form8-K within four (4) business days of the day the final results are available.

Implications of being an “emerging growth company.”

We are an “emerging growth company” as that term is used in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”) and, as such, have elected to comply with certain reduced public company reporting requirements. These reduced reporting requirements include reduced disclosure about our executive compensation arrangements and nonon-binding advisory votes on executive compensation. We will remain an emerging growth company until the earlier of: (1) December 31, 2023, (2) the last day of the fiscal year in which we have total annual gross

revenue of at least $1.07 billion, (3) the last day of the fiscal year in which we are deemed to be a “large accelerated filer” as defined in Rule12b-2 under the Securities Exchange Act of 1934, as amended, which would occur if the market value of our common stock held bynon-affiliates exceeded $700.0 million as of the last business day of the second fiscal quarter of such year or (4) the date on which we have issued more than $1.0 billion innon-convertible debt securities during the prior three-year period.

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PROPOSAL NO. 1


ELECTION OF DIRECTORS

Our boardBoard of directorsDirectors is divided into three classes. Each class consists, as nearly as possible, ofone-third of the total number of directors, and each class has a staggered, three-year term. Unless the boardBoard of directorsDirectors determines that vacancies (including vacancies created by increases in the number of directors) shall be filled by the stockholders, and except as otherwise provided by law, vacancies on the boardBoard of directorsDirectors may be filled only by the affirmative vote of a majority of the remaining directors. A director elected by the boardBoard of directorsDirectors to fill a vacancy (including a vacancy created by an increase in the number of directors) shall serve for the remainder of the full term of the class of directors in which the vacancy occurred and until such director’s successor is elected and qualified.

The board

Our Board of directorsDirectors currently consists of seven seated directors, divided into the three following classes:

•

Class I directors:Andrew Allen, M.D., Ph.D. and Judith Li, whose current terms will expire at the Annual Meeting;

•

Class II directors:Richard Heyman, Ph.D., Thomas Woiwode, Ph.D., and Nicholas Simon, whose current terms will expire at the annual meeting of stockholders to be held in 2020; and

•

Class III directors:Steve Krognes and Peter Svennilson, whose current terms will expire at the annual meeting of stockholders to be held in 2021.

Class I directors: Andrew Allen, M.D., Ph.D., and Naiyer Rizvi, M.D., whose current terms will expire at the Annual Meeting;
Class II directors: Richard Heyman, Ph.D., and Shefali Agarwal, M.D., M.P.H., whose current terms will expire at the annual meeting of stockholders to be held in 2023; and
Class III directors: Steve Krognes, Clare Fisher and Elaine Jones, Ph.D., whose current terms will expire at the annual meeting of stockholders to be held in 2024.
At each annual meeting of stockholders, the successors to directors whose terms will then expire will be elected to serve from the time of election and qualification until the third subsequent annual meeting of stockholders.

Dr.

Drs. Allen and Ms. LiRizvi have been nominated to serve as Class I directors and have each elected to stand for reelection. Each director to be elected will hold office from the date of theirhis or her election by the stockholders until the third subsequent annual meeting of stockholders or until his or her successor is elected and has been qualified, or until such director’s earlier death, resignation or removal.

Shares represented by executed proxies will be voted, if authority to do so is not withheld, for the election of the two nominees named below. In the event that any nominee should be unavailable for election as a result of an unexpected occurrence, such shares will be voted for the election of such substitute nominee as the boardBoard of directorsDirectors may propose. Each person nominated for election has agreed to serve if elected, and management has no reason to believe that any nominee will be unable to serve. Directors are elected by a plurality of the votes cast at the meeting.

The following table sets forth, for the Class I nominees (who are currently standing forre-election) and for our other current directors who will continue in office after the Annual Meeting, information with respect to their ages as of April 22, 201920, 2022 and position/office held within the Company:

Name

  Age  

Position/Office Held With the Company

  Director
Since		 

Class I Directors whose terms expire at the Annual Meeting

 

Andrew Allen, M.D., Ph.D.

  52  President, Chief Executive Officer and Director   2015 

Judith Li(1)

  35  Director   2017 

Class II Directors whose terms expire at the 2020 Annual Meeting of Stockholders

 

Richard Heyman, Ph.D.(1)(2)

  61  Director   2015 

Thomas Woiwode, Ph.D.(1)(2)

  47  Director   2015 

Nicholas Simon(3)

  65  Director   2015 

Class III Directors whose terms expire at the 2021 Annual Meeting of Stockholders

 

Steve Krognes(2)(3)

  50  Director   2018 

Peter Svennilson(3)

  57  Director   2015 

Name
​​
Class
​​
Age
​​
Position/Office
​​
Director Since
Andrew Allen, M.D., Ph.D.
​​
I
​​
55
​​
President, Chief Executive Officer and Director
​​
2015
Naiyer Rizvi, M.D.(3)
​​
I
​​
58
​​
Director
​​
2021
Richard Heyman, Ph.D.(1)(2)
​​
II
​​
64
​​
Director
​​
2015
Shefali Agarwal, M.D., M.P.H.(2)
​​
II
​​
48
​​
Director
​​
2021
Steve Krognes(2)(3)
​​
III
​​
53
​​
Director
​​
2018
Clare Fisher(1)
​​
III
​​
49
​​
Director
​​
2022
Elaine Jones, Ph.D.(1)(3)
​​
III
​​
67
​​
Director and Chairperson of the Board of Directors
​​
2020

(1)

Member of the nominating and corporate governance committee.

(2)

Member of the compensation committee.

(3)

Member of the audit committee.

Set forth below is biographical information for the nominees and each person whose term of office as a director will continue after the Annual Meeting. The following includes certain information regarding our directors’ individual experience, qualifications, attributes and skills that led the boardBoard of directorsDirectors to conclude that they should serve as directors.
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Nominees for Election to a Three-Year Term Expiring at the 20222025 Annual Meeting of Stockholders

Andrew Allen, M.D., Ph.D. has served as a member of our Board of Directors since August 2015. Dr. Allen co-founded Gritstone Oncology, Inc. and has served as our President and Chief Executive Officer and a member of our board of directors since SeptemberAugust 2015. Prior to Gritstone, in April 2009, Dr. Allenco-founded Clovis Oncology, Inc., a public pharmaceutical development company, and served as its executive vice presidentExecutive Vice President of clinicalClinical and preclinical developmentPreclinical Development and chief medical officerChief Medical Officer from April 2009 to July 2015. Prior to that, he was chief medical officerChief Medical Officer at Pharmion Corporation, a biotechnology company that was ultimately acquired by Celgene Corporation, from 2006 to 2008. Previously, Dr. Allen served in clinical development leadership roles at Chiron Corporation, a biotechnology company that was ultimately acquired by Novartis International AG, and Abbott Laboratories, a public medical devices and healthcare company, and worked at McKinsey & Company, where he advised life science companies on strategic issues. He currently serves on the boardboards of directors of Epizyme, Inc., a publicly traded biopharmaceutical company, Sierra Oncology, Inc., a public biopharmaceutical company, TCR2TCR2 Therapeutics Inc, a public biopharmaceutical company, and Revitope Inc., a privately-heldprivate biotechnology company, and Verge Genomics, Inc., a private biotechnology company. Dr. Allen previously served on the boardboards of directors of Cell Design Labs, Inc. a private biotechnology company, from November 2015 until its acquisition by Gilead Sciences, Inc. in December 2017.2017, and Epizyme, Inc. (“Epizyme”), a public biopharmaceutical company, from June 2014 until November 2021. Dr. Allen qualified in medicine at Oxford University and received a Ph.D. in immunology from Imperial College of Science, Technology and Medicine in London.
We believe that Dr. Allen is qualified to serve on our boardBoard of directorsDirectors due to his educational experience and his experience as a senior executive of public and private biotechnology and pharmaceutical companies, including his service as our chief executive officer.

Judith LiChief Executive Officer.

Dr. Naiyer A. Rizvi is our co-founder and has served as a member of our boardBoard of directorsDirectors since September 2017. Ms. Li has served asJune 2021. Dr. Rizvi is Chief Medical Officer at Synthekine, a partnerprivate, engineered and synthetic cytokine therapeutics company. Until May 2021, he was the Price Family Professor of Medicine, Director of Thoracic Oncology and Co-Director of Cancer Immunotherapy at Lilly Asia Ventures, or LAV, which is basedColumbia University Medical Center. He received an M.D. at the University of Manitoba in Hong KongWinnipeg, Canada, and Shanghaicompleted a fellowship in medical oncology at Beth Israel Hospital/Harvard Medical School. From 1990 to 1995, Dr. Rizvi was an attending physician in thoracic oncology and focusesearly drug development at Memorial Sloan Kettering Cancer Center, where his translational research focused on early and growth stage investments across biopharmaceuticals, medical devices, and diagnostics both domestically and cross-border, since 2013. Judith currently holds board appointments at a variety of LAV’s private portfolio companies, including Just Biotherapeutics, Inc., Veritas Genetics Inc., and Nextcure, Inc. From April 2014 to October 2017, she served on the board of Crown BioScience Inc., a biotechnology company which was publicly listed on the Taiwan Stock Exchange until it was acquired in December 2017. Currently, Ms. Li serves on the board of directors of Inhibrx, Inc. a public biopharmaceutical company. Previously, Ms. Li served as a senior business analyst at McKinsey & Company, worked in hospital administration at Partners Healthcare, andco-foundedimmune-checkpoint blockade drug development. an interventional nephrology medical device venture. Judith holds a B.A. in biology from Harvard and an M.B.A. from Harvard Business School.
We believe that Ms. LiDr. Rizvi is qualified to serve on our boardBoard of directorsDirectors due to herhis educational background and his experience as a board member and senior executive of biotechnology and pharmaceutical companies, and her experience as an investor in new life sciences companies.

THE BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS A VOTE “FOR”

“FOR”

THE ELECTION OF EACH NAMED NOMINEE.
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Directors Continuing in Office Until the 20202023 Annual Meeting of Stockholders

Richard Heyman, Ph.D. has served as a member of our boardBoard of directorsDirectors since November 2015. Dr. Heyman is executive chairman andco-founder of Metacrine, Inc., a public biotechnology company developing new therapeutics for the treatment of liver and gastrointestinal diseases. He also is theco-founder and chairman of ORIC Pharmaceuticals, which isInc., a public biotechnology company developing drugs to overcome resistance in cancer. Previously, Dr. Heyman

served as presidentPresident and chief executive officerChief Executive Officer of Seragon Pharmaceuticals Inc. (“Seragon”), or Seragon, a privately-heldprivate biotechnology company, which was acquired by Genentech, Inc. (“Genentech”) in 2014. Prior to Seragon, heco-founded and served as presidentPresident and chief executive officerChief Executive Officer of Aragon Pharmaceuticals, Inc., or Aragon, until it was purchased by Johnson & Johnson in 2013. He has been involved in the discovery and development of multiple therapeutic agents approved by the FDA, including the recently approved prostate cancer drug, Erleada. Dr. Heyman is a venture partner for Arch Ventures and serves on the Board of Directors for YmanityYumanity Therapeutics Inc., a public biotechnology company and Vividion Therapeutics.chairman of PMV Pharmaceuticals, Inc., a public precision oncology company. He is Vice Chair of the Board of Trustees at the Salk Institute, on the Board Foundation for the American Association for Cancer Research or AACR,(AACR) and on the executive committee at the University of California at San Diego Moores Cancer Center. He has won numerous awards, including Ernst and Young San Diego Regional Entrepreneur of the Year and the Endocrine Society Outstanding Innovation Award. Dr. Heyman received a B.S. in chemistry from the University of Connecticut and a Ph.D. in pharmacology from the University of Minnesota. He was an NIH post-doctoral fellow and staff scientist at the Salk Institute.

We believe that Dr. Heyman is qualified to serve on our boardBoard of directorsDirectors due to his educational background and his experience as a board member and senior executive of biotechnology and pharmaceutical companies.

Nicholas Simon

Dr. Shefali Agarwal has served as a member of our boardBoard of directorsDirectors since September 2015. Mr. SimonJune 2021. Dr. Agarwal is President and Chief Executive Officer of Onxeo S.A. (“Onxeo”), a Senior Managing Directorpublic clinical stage biotechnology company specializing in the Blackstone Life Sciences group, having joined Blackstonedevelopment of innovative drugs targeting tumor DNA damage response. Dr. Agarwal also serves as part of its acquisition of Clarus Ventures, LLC, or Clarus, in December of 2018.Acting Chief Medical and Development Officer at Epizyme, a public fully-integrated, commercial-stage biopharmaceutical company developing and delivering novel epigenetic therapies. Previously, until April 2022, Dr. Agarwal served as Executive Vice President and Chief Medical and Development Officer at Epizyme. Prior to joining Blackstone, Mr. Simon wasco-founderEpizyme in 2018, she held leadership positions across medical research, clinical development, clinical operations and Managing Director of Clarus,medical affairs. Dr. Agarwal also served as Chief Medical Officer at SQZ Biotech, Inc. (“SQZ Biotech”), a venture capital firm focused on life sciences companies, sincepublic biotechnology company, where she built and led the firm’s inception in 2005. Prior to Clarus, Mr. Simon was a general partnerclinical development organization, which included clinical research operations and the regulatory function. Before SQZ Biotech, Dr. Agarwal also held leadership positions at MPM Capital,Curis, Inc., a healthcare venture capital firm. Hepublic biotechnology company, and Tesaro, Inc., a biotechnology company that was ultimately acquired by GlaxoSmithKline plc. Dr. Agarwal has more than 20 yearsalso held positions of operatingincreasing responsibility at Covidien, AVEO Pharmaceuticals, Inc. and investment experience in the biopharmaceutical industry including serving as vice president of business and corporate development at Genentech from 1989 to 2000. In addition to Gritstone, Mr. Simon is currently a member of the board of directors of Nuvelution Pharma,Pfizer, Inc. (“Pfizer”), a public pharmaceutical company, andcompany. Dr. Agarwal currently sits on the Board of Lycera Corp., a private pharmaceutical company, as well as chairmanDirectors of the board of Sientra,Fate Therapeutics, Inc., a public biotechnology company. In addition to receiving her medical aesthetics company. He has also beendegree from Bangalore University, Dr. Agarwal holds a membermaster of the boardpublic health from Johns Hopkins University and a master of directors of numerous private and public life sciences companies including Achillion Pharmaceuticals, Inc., Avanir Pharmaceuticals, Inc., Barrier Therapeutics, Inc., Biovitrum AB, CoTherix, Inc., InterMune, Inc., Pearl Therapeutics Inc., QuatRx Pharmaceuticals Co., Rigel Pharmaceuticals, Inc., and Sangstat Medical Corporation. Mr. Simon is also a trustee at the Gladstone Institute, a privatenot-for-profit research institute affiliated with the University of California, San Francisco. Mr. Simon received a B.S.science in microbiologybusiness from the University of Maryland and an M.B.A. from Loyola University. Maryland.
We believe that Mr. SimonDr. Agarwal is qualified to serve on our boardBoard of directorsDirectors due to his experience as a board member of biotechnology and pharmaceutical companies, and his experience as an investor in new life sciences companies.

Thomas Woiwode, Ph.D. has served as a member of our board of directors since September 2015. Dr. Woiwode has been with Versant Venture Management, LLC, or Versant Ventures, a healthcare investment firm, since 2002 in various capacities, serving as a managing director since July 2014 and previously as a venture partner from June 2011 to July 2014. He has also served in a number of operating roles over this time, most recently as the chief operating officer of Okairos AG, or Okairos, a biopharmaceutical company developing genetic vaccines for major infectious diseases, from April 2011 until May 2013. Prior to Okairos, Dr. Woiwodeco-founded EuroVentures, a wholly owned biotechnology incubator within Versant Ventures, and in this role, served as the founding chief business officer for three biotechnology companies created within Versant Ventures. Before joining Versant Ventures, Dr. Woiwode also served as a research scientist at XenoPort, Inc. Dr. Woiwode currently serves on the board of directors of CRISPR Therapeutics AG and Adverum Biotechnologies, Inc., and served on the board of directors of Audentes Therapeutics, Inc. from July 2013 to July 2017. Dr. Woiwode also serves on the board of directors of several private companies. Dr. Woiwode holds a B.A. in English and a B.S. in Chemistry from the University of California, Berkeley and a Ph.D. in Organic Chemistry as an NSF Fellow from Stanford University. We believe that Dr. Woiwode is qualified to serve on our board of directors due to hisher educational background hisand her experience as a board member and senior executive of biotechnology and pharmaceutical companies.

Directors Continuing in Office Until the 2024 Annual Meeting of Stockholders
Elaine Jones, Ph.D. has served as a member and chairperson of our Board of Directors since May 2020. Previously, Dr. Jones was a Vice President, Worldwide Business Development and Senior Partner at Pfizer Ventures, the venture capital arm of Pfizer Inc., from 2008, when she joined as an Executive Director, until her retirement in April 2019. At Pfizer Ventures, Dr. Jones was responsible for making and managing venture investments for Pfizer as well as serving on the boards of directors of several biotechnology platform and therapeutic companies. Prior to this, Dr. Jones held the position of General Partner at EuclidSR Partners, a venture firm specializing in investment in private and public equity within the health sciences, healthcare, and biopharmaceutical sectors, until 2008. Dr. Jones began her investment career at S.R. One, the corporate investment fund of GlaxoSmithKline plc, a public pharmaceutical company, where she served from 1999 to 2003. Prior to this, Dr. Jones served as Director of Scientific Licensing at SmithKline Beecham and as a research
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scientist in the Research and Development division of SmithKline Beecham Pharmaceuticals. During her venture career, Dr. Jones has served on the boards of directors of more than 20 early to mid-stage biotechnology, therapeutic and pharmaceutical companies. Dr. Jones holds a B.S. in biology from Juniata College and a Ph.D. in microbiology from the University of Pittsburgh.
We believe that Dr. Jones is qualified to serve on our Board of Directors due to her educational background, her knowledge of the pharmaceutical industry, her experience as a board member of biotechnology and pharmaceutical companies, and hisher experience as an investor in new life sciences companies.

Directors Continuing in Office Until the 2021 Annual Meeting of Stockholders

Steve Krognes has served as a member of our boardBoard of directorsDirectors since July 2018. Mr. Krognes has served as chief financial officerChief Financial Officer of Denali Therapeutics Inc. (“Denali”), or Denali, sincea public biotechnology company, from October 2015.2015 to March 2022. Mr. Krognes joined Denali from Genentech, a private biotechnology company, where he served as chief financial officerChief Financial Officer and a member of the executive committee from April 2009 to September 2015. Mr. Krognes also oversaw Genentech’s site services organization between 2011 and 2015, and Genentech’s information technology organization between 2009 and 2011. He chaired the Genentech Access to Care Foundation between 2009 and 2015. From January 2004 to April 2009, Mr. Krognes served as headHead of mergersMergers and acquisitionsAcquisitions and a member of the finance executive committee at Roche, a public Swiss biotechnology company. From July 2002 to December 2003, Mr. Krognes served as directorDirector of mergersMergers and acquisitionsAcquisitions at Danske Bank, based in Norway. From April 2000 to June 2002, he was a venture capitalist with Pylonia Ventures, a Swedish venture investments company. Prior to that, Mr. Krognes worked as a consultant at McKinsey & Company and an investment banker at Goldman Sachs, based in London and Boston. Mr. Krognes currently serves as a member of the boardsboard of directors of Corvus Pharmaceuticals, a publicly traded biopharmaceutical company, and RLS Global AB, a Swedish life sciences company. Mr.Mr Krognes also served as a board memberon the boards of directors of Corvus Pharmaceuticals between 2016 and 2020, the California Life Sciences Association between 2010 and 2015, and the California Academy of Sciences a private scientific and educational institution, between 2014 and 2018. He received his M.B.A. from Harvard Business School and his B.S. in economics from the Wharton School of the University of Pennsylvania.

We believe that Mr. Krognes is qualified to serve on our boardBoard of directorsDirectors due to his educational background and his experience as a board member and senior executive of biotechnology and pharmaceutical companies.

Peter Svennilson

Clare Fisher has served as a member of our boardBoard of directorsDirectors since September 2015. In February 2007, Mr. Svennilson founded The Column Group, LP, or The Column Group, a San Francisco-based biotechnology venture capital firm, andJanuary 2022. Ms. Fisher currently serves as its managing partner. Mr. Svennilson also currently serves asSenior Vice President of Business Development and Mergers and Acquisitions at BeiGene, Ltd. (“BeiGene”), a memberglobal, science-driven biotechnology company focused on developing innovative and affordable medicines to improve treatment outcomes and access for patients worldwide. Ms. Fisher has over 20 years of the boardexperience in healthcare corporate and business development, leading collaborations, licensing, mergers and acquisitions, investments and divestments across many technologies and therapeutic areas. Prior to joining BeiGene, Ms. Fisher was Chief Business Officer of two other public companies, NGM Biopharmaceuticals, Inc. and Constellation Pharmaceuticals. In addition, Mr. Svennilson serves on the board of ORIC Pharmaceuticals,Kaleido Bioscience, Inc., a private biotechnology company. Previously, he servedpublic company dedicated to targeting the microbiome to treat a variety of diseases, and held senior global roles at Shire plc, Cubist Pharmaceuticals, Blueprint Medicines, Corp. and Genzyme Corporation. Ms. Fisher holds a B.S. in Biochemistry from the University of Bath, as chairman of the board of Seragon from January 2008 until it was acquired by Genentech in August 2014. He was the chairman of the board of Aragon from May 2009 until it was acquired by Johnson & Johnson in August 2013. Mr. Svennilson was also a board member of Ribon Therapeutics, Inc., a private biotechnology company from 2017 to 2019, Immune Design Corp., from 2014 until 2018, and PTC Therapeutics, Inc. from 2012 until 2014. Prior to founding The Column Group, he founded Three Crowns Capital, where he servedwell as its managing partner from June 1996 to February 2007. From 1996 to 2006, Mr. Svennilson served as a board member of multiple biotechnology companies, including Rosetta Inpharmatics LLC, ChemoCentryx, Inc. and Somalogic, Inc. Prior to founding Three Crowns Capital, from 1987 to 1993 he was the associate managing director in charge of European Investment Banking Origination at Nomura Securities in London. Mr. Svennilson is currently a trustee for the Institute for Advanced Study in Princeton, New Jersey. Mr. Svennilson received an M.B.A. from Henley Management College in the Stockholm School of Economics and Finance. United Kingdom.
We believe that Mr. SvennilsonMs. Fisher is qualified to serve on our boardBoard of directorsDirectors due to hisher educational background and experience in the venture capital industryas senior executive of biotechnology and in serving as a director of other public life sciencepharmaceutical companies.
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PROPOSAL NO. 2


RATIFICATION OF SELECTION OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The audit committee of our boardBoard of directorsDirectors has engaged Ernst & Young LLP (“EY”), as our independent registered public accounting firm for the year ending December 31, 2019,2022, and is seeking ratification of such selection by our stockholders at the Annual Meeting. EY has audited our financial statements for each of our fiscal years since the fiscal year ended December 31, 2015. Representatives of EY are expected to be in attendance online at the Annual Meeting. They will have an opportunity to make a statement if they so desire and will be available to respond to appropriate questions.

Neither

Nothing in our bylaws noror other governing documents, or in any applicable law, requirerequires stockholder ratification of the selection of EY as our independent registered public accounting firm. However, the audit committee is submitting the selection of EY to our stockholders for ratification as a matter of good corporate practice. If our stockholders fail to ratify the selection, the audit committee will reconsider whether or not to retain EY. Even if the selection is ratified, the audit committee in its discretion may direct the appointment of a different independent registered public accounting firm at any time during the year if they determine that such a change would be in the best interests of the Company and our stockholders.

Principal Accountant Fees and Services

The following table provides information regarding the fees incurred to EY during the years ended December 31, 20182021 and 2017.2020. The audit committee approved all of the fees described below and incurred since our initial public offering (“IPO”) in October 2018.

   Year Ended
December 31,		 
   2018   2017 

Audit Fees(1)

  $2,044,000   $281,000 

Audit-Related Fees(2)

   —      —   

Tax Fees(3)

   22,000    —   

All Other Fees(4)

   3,000    —   
  

 

 

   

 

 

 

Total Fees

  $2,069,000   $281,000 
  

 

 

   

 

 

 

the respective periods.
 
​​
Year Ended
December 31,
 
​​
2021
​​
2020
Audit Fees(1)
​​
$1,282,000
​​
$949,000
Audit-Related Fees(2)
​​
—
​​
—
Tax Fees(3)
​​
$23,000
​​
—
All Other Fees(4)
​​
—
​​
4,000
Total Fees
​​
$1,305,000
​​
$953,000
(1)

Audit fees are fees for professional services for the audit of the Company’s 2018our 2021 and 20172020 consolidated financial statements, the review of quarterly consolidated financial statements, and for services that are normally provided by the accountant in connection with other statutory and regulatory filings or engagements. Fees for the year ended December 31, 2018 include services associated with our IPO, which was completed in October 2018.

(2)

Audit-related fees are fees for assurance and related services that are reasonably related to the performance of the audit or review of a company’sour consolidated financial statements.

(3)

Tax fees are fees for tax compliance, tax advice and tax planning.

(4)

Represents fees related to accessing Ernst & Young LLP’sEY’s online research database in 2018.

database.

Pre-Approval Policies and Procedures

The audit committee, or a delegate of the audit committee,pre-approves, or provides pursuant topre-approvals, policies and procedures for thepre-approval of, all audit andnon-audit services provided by its independent registered public accounting firm. This policy is set forth in the charter of the audit committee and is available at http://www.gritstoneoncology.com.

www.gritstonebio.com.

The audit committee approved all of the audit, audit-related, tax and other services provided by EY for 2017 and alleach of the audit, audit-related, taxyears ended December 31, 2020 and other services provided by EY in 2018 following our IPO in October 20182021 and, in each case, the estimated costs of thosesuch services. Actual amounts billed, to the extent in excess of the estimated amounts, are periodically reviewed and approved by the audit committee.

THE BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS A VOTE “FOR”

“FOR”

THE RATIFICATION OF OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM.
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REPORT OF THE AUDIT COMMITTEE OF THE BOARD OF DIRECTORS

The material in this report is not “soliciting material,” is not deemed “filed” with the SEC and is not to be incorporated by reference into any filing of Gritstone under the Securities Act of 1933, as amended (the “Securities Act”), or the Securities Exchange Act of 1934, as amended.

Act.

The primary purpose of the audit committee is to oversee our financial reporting processes on behalf of our boardBoard of directors.Directors. The audit committee’s functions are more fully described in its charter, which is available on our website at http://www.gritstoneoncology.com.www.gritstonebio.com. Management has the primary responsibility for our consolidated financial statements and reporting processes, including our systems of internal controls. In fulfilling its oversight responsibilities, the audit committee reviewed and discussed with management Gritstone’s audited consolidated financial statements as of and for the year ended December 31, 2018.

2021.

The audit committee has discussed with Ernst & Young LLP (“EY”), the Company’s independent registered public accounting firm, the matters required to be discussed by Auditing Standard No. 1301, “Communications with Audit Committees” issued bythe applicable requirements of the Public Company Accounting Oversight Board (the “PCAOB”(“PCAOB”) and the Securities and Exchange Commission (“SEC”). In addition, the audit committee discussed with EY their independence and received from EY the written disclosures and the letter required by Ethics and Independence Rule 3526 of the PCAOB. Finally, the audit committee discussed with EY, with and without management present, the scope and results of EY’s audit of such financial statements.

Based on these reviews and discussions, the audit committee has recommended to our boardBoard of directorsDirectors that such audited consolidated financial statements be included in our Annual Report on Form10-K for the year ended December 31, 20182021 for filing with the SEC. The audit committee also has engaged EY as our independent registered public accounting firm for the fiscal year ending December 31, 20192022 and is seeking ratification of such selection by the stockholders.

Audit Committee


Steve Krognes, ChairChairperson
Naiyer Rizvi, M.D.
Elaine Jones, Ph.D.
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Nicholas Simon

Peter Svennilson

CORPORATE GOVERNANCE

Code of Business Conduct and Ethics

We have adopted a code of business conduct and ethics that applies to all of our employees, officers and directors, including those officers responsible for financial reporting. The code of business conduct and ethics is available on our website at http://www.gritstoneoncology.com.www.gritstonebio.com. Any amendments to the code, or any waivers of its requirements, will be disclosed on our website.

Corporate Governance Guidelines

We believe in sound corporate governance practices and have adopted formal corporate governance guidelines to enhance our effectiveness. Our boardBoard of directorsDirectors adopted these corporate governance guidelines in order to ensure that it has the necessary practices in place to review and evaluate our business operations as needed and to make decisions that are independent of our management. The corporate governance guidelines are also intended to align the interests of directors and management with those of our stockholders. The corporate governance guidelines set forth the practices our boardBoard of directorsDirectors follows with respect to boardBoard of directorsDirectors and committee composition and selection, boardmeetings of directors meetings,the Board of Directors, Chief Executive Officer performance evaluation and succession planning. A copy of our corporate governance guidelines is available on our website at http://www.gritstoneoncology.com.

www.gritstonebio.com.

Independence of the Board of Directors

As required under the

The Nasdaq Global Select MarketMarket’s (“Nasdaq”) rules and regulations, a majority of the members of a listed company’s board of directors must qualify as “independent,” as affirmatively determined by such board. The boardBoard of directorsDirectors consults with the Company’s counsel to ensure that the boardBoard of directors’Directors’ determinations are consistent with all relevant securities and other laws and regulations regarding the definition of “independent,” including those set forth in pertinent Nasdaq listing standards, as in effect from time to time.

Consistent with these considerations, our boardBoard of directorsDirectors has determined that all of our directors, other than Dr. Allen, qualify as “independent” directors in accordance with the Nasdaq listing requirements. Dr. Allen is not considered independent because he is an employee of Gritstone. The Nasdaq independence definition includes a series of objective tests, such as that the director is not, and has not been for at least three years, one of our employees and that neither the director nor any of his or her family members has engaged in various types of business dealings with us. In addition, as required by Nasdaq rules, our boardBoard of directorsDirectors has made a subjective determination as to each independent director that no relationships exist, which, in the opinion of our boardBoard of directors,Directors, would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In making these determinations, our boardBoard of directorsDirectors considered 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. There are no family relationships among any of our directors or executive officers.

As required under Nasdaq rules and regulations, our independent directors meet in regularly scheduled executive sessions at which only independent directors are present. All of the committees of our boardBoard of directorsDirectors are comprised entirely of directors determined by the boardBoard of directorsDirectors to be independent within the meaning of Nasdaq and SEC rules and regulations applicable to the members of such committees.

Leadership Structure of the Board

Our bylaws and corporate governance guidelines provide our boardBoard of directorsDirectors with flexibility to combine or separate the positions of Chairmanchair of the boardBoard of directorsDirectors and Chief Executive Officer and to implement a leadOfficer. Since May 2020, Elaine Jones, Ph.D., who is considered an independent director, in accordance with its determination that utilizing one or the other structure would be in the best interestshas served as chairperson of our Company. While we do not currently have an appointed Chairman or lead independent director,Board of Directors. Dr. HeymanJones presides over theour executive sessions of the board of directors and acts as a liaison between our management and the boardBoard of directors.

Directors.

Our boardBoard of directorsDirectors has concluded that our current leadership structure is appropriate at this time. However, our boardBoard of directorsDirectors will continue to periodically review our leadership structure and may make such changes in the future as it deems appropriate.

Role of Board in Risk Oversight Process

Risk assessment and oversight are an integral part of our governance and management processes. Our boardBoard of directorsDirectors encourages management to promote a culture that incorporates risk management into our corporate
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strategy andday-to-day business operations. Management discusses strategic and operational risks at regular management meetings and conducts specific strategic planning and review sessions during the year that include a focused discussion and analysis of the risks facing us. Throughout the year, senior management reviews these risks with the boardBoard of directorsDirectors at regular board meetings as part of management presentations that focus on particular business functions, operations or strategies and presents the steps taken by management to mitigate or eliminate such risks.

Our boardBoard of directorsDirectors does not have a standing risk management committee, but rather administers this oversight function directly through our boardBoard of directorsDirectors as a whole, as well as through various standing committees of our boardBoard of directorsDirectors that address risks inherent in their respective areas of oversight. In particular, our boardBoard of directorsDirectors is responsible for monitoring and assessing strategic risk exposure, and our audit committee is responsible for overseeing our major financial risk exposures and the steps our management has taken to monitor and control these exposures. The audit committee also monitors compliance with legal and regulatory requirements. Our nominating and governance committee monitors the effectiveness of our corporate governance guidelines and considers and approves or disapproves any related-person transactions. Our compensation committee assesses and monitors whether any of our compensation policies and programs has the potential to encourage excessive risk-taking.

Board Committees

Audit Committee

Our audit committee oversees our corporate accounting and financial reporting process. Among other matters, the audit committee:

appoints our independent registered public accounting firm;

evaluates the independent registered public accounting firm’s qualifications, independence and performance;

determines the engagement of the independent registered public accounting firm;

reviews and approves the scope of the annual audit and the audit fee;

discusses with management and the independent registered public accounting firm the results of the annual audit and the review of our quarterly consolidated financial statements;

approves the retention of the independent registered public accounting firm to perform any proposed permissiblenon-audit services;

monitors the rotation of partners of the independent registered public accounting firm on our engagement team in accordance with requirements established by the SEC;

is responsible for reviewing our consolidated financial statements and our management’s discussion and analysis of financial condition and results of operations to be included in our annual and quarterly reports to be filed with the SEC;

reviews our critical accounting policies and estimates;

reviews all related party transactions on an ongoing basis;

establishes procedures for the receipt, retention and treatment of complaints received by us regarding accounting, internal controls or auditing matters;

annually reviews and assesses treasury functions, including cash management process;

discusses on a periodic basis, or as appropriate, with management our policies, programs and procedurescontrols with respect to risk assessment;

assessment and risk management;
reviews our compliance and ethics programs, including legal and regulatory requirements;
consults with management to establish procedures and internal controls relating to cybersecurity;
reviews management’s report on its assessment of the effectiveness of internal control over financial reporting and any changes thereto;
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investigates any matters received, and reports to the Board periodically, with respect to ethics issues, complaints and associated investigations; and

reviews the audit committee charter and the committee’s performance at least annually.

The current

From January 1 to June 1, 2021, the members of our audit committee arewere Messrs. Krognes and Simon and Svennilson.Dr. Jones; following Mr. Simon’s resignation from the Board, effective June 1, 2021, Dr. Rizvi was appointed to fill Mr. Simon’s seat on the audit committee. Mr. Krognes and Drs. Rizvi and Jones continue to serve on the audit committee. Mr. Krognes serves as the chairperson of the committee. All members of our audit committee meet the requirements for financial literacy under the applicable rules and regulations of the SEC and Nasdaq. Our boardBoard of directorsDirectors has determined that Mr. Krognes is an audit committee financial expert as defined under the applicable rules of the SEC and has the requisite financial sophistication as defined under the applicable rules and regulations of Nasdaq. Under the rules of the SEC, members of the audit committee must also meet heightened independence standards. Our boardBoard of directorsDirectors has determined that each of the members of our audit committee areis independent under the applicable rules of the SEC and Nasdaq. The audit committee operates under a written charter that satisfies the applicable standards of the SEC and Nasdaq. A copy of the audit committee charter is available to security holders on the Company’s website at http://www.gritstoneoncology.com.

www.gritstonebio.com.

Compensation Committee

Our compensation committee oversees policies relating to compensation and benefits of our officers and employees.employees other than our Chief Executive Officer, with respect to whom our Board of Directors retains the authority to make compensation decisions. The compensation committee reviews and approves or recommends corporate goals and objectives relevant to compensation of our executive officers (other than our Chief Executive Officer), evaluates the performance of these officers in light of those goals and objectives and approves the compensation of these officers based on such evaluations. The compensation committee also reviews and approves or makes recommendations to our boardBoard of directorsDirectors regarding the issuance of stock options and other awards under our stock plans to our executive officers (other than our Chief Executive Officer). The compensation committee also reviews the performance of our Chief Executive Officer and makes recommendations to our boardBoard of directorsDirectors with respect to his compensation, and our boardwhile the Board of directors retains the authority to make compensation decisions relative to our Chief Executive Officer.Directors as a whole makes any final decisions. The compensation committee will review and evaluate, at least annually, the performance of the compensation committee and its members, including compliance by the compensation committee with its charter. The current members of our compensation committee are Mr. Krognes and Drs. WoiwodeAgarwal and Heyman and Mr. Krognes.Heyman. Dr. WoiwodeHeyman serves as the chairperson of theour compensation committee. Each of the membersmember of our compensation committee is independent under the applicable rules and regulations of Nasdaq and is a“non-employee “non-employee director” as defined in Rule16b-3 promulgated under the Exchange Act. The compensation committee operates under a written charter that satisfies the applicable standards of the SEC and Nasdaq. A copy of the compensation committee charter is available to security holders on the Company’s website at http://www.gritstoneoncology.com.

www.gritstonebio.com.

Our compensation committee has retained Radford, Inc.the Human Capital Solutions subdivision of Aon plc (“Radford”Aon”), a national compensation consulting firm, to serve as its independent compensation consultant and to conduct market research and analysis on our various executive positions, to assist the committee in developing appropriate incentive plans for our executives on an annual basis, to provide the committee with advice and ongoing recommendations regarding material executive compensation decisions, and to review compensation proposals of management. RadfordAon reports directly to the compensation committee and does not provide anynon-compensation related services to the Company. The compensation committee reviewed the independence of Radford,Aon, employing the independence factors specified in the listing requirements of Nasdaq. Based on this assessment, the compensation committee determined that the engagement of RadfordAon does not raise any conflicts of interest or similar concerns. In

addition, the compensation committee evaluated the independence of its other outside advisors, to the compensation committee, including outside legal counsel, considering the same independence factors, and concluded that their work for the compensation committee does not raise any conflicts of interest.

Nominating and Corporate Governance Committee

The nominating and corporate governance committee is responsible for making recommendations to our boardBoard of directorsDirectors regarding candidates for directorships and the size and composition of our boardBoard of directors.Directors. In addition, the nominating and corporate governance committee is responsible for overseeing our corporate governance policies and reporting and making recommendations to our boardBoard of directorsDirectors concerning
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governance matters. The current members of our nominating and corporate governance committee are Ms. Fisher and Drs. Heyman and Woiwode and Ms. Li. Ms. LiJones. Dr. Jones serves as the chairperson of the committee. Each of the membersmember of our nominating and corporate governance committee is an independent director under the applicable rules and regulations of Nasdaq relating to nominating and corporate governance committee independence. The nominating and corporate governance committee operates under a written charter that satisfies the applicable standards of the SEC and Nasdaq. A copy of the nominating and corporate governance committee charter is available to security holders on the Company’s website at http://www.gritstoneoncology.com.

www.gritstonebio.com.

The nominating and corporate governance committee will consider director candidates recommended by stockholders. ForPursuant to our bylaws, for a stockholder to make any nomination for election to the boardBoard of directorsDirectors at an annual meeting, the stockholder must provide notice to the Company, which notice must be delivered to, or mailed and received at, the Company’sour principal executive offices not less than 90 days and not more than 120 days prior to theone-year anniversary of the preceding year’s annual meeting; provided that, if the date of the annual meeting is more than 30 days before or more than 60 days after such anniversary date, the stockholder’s notice must be delivered, or mailed and received, not later than 90 days prior to the date of the annual meeting or, if later, the 10th day following the date on which public disclosure of the date of such annual meeting is made. Further updates and supplements to such notice may be required at the times, and in the forms, required under our bylaws. As set forth in our bylaws, submissions must include the name and address of the proposed nominee, information regarding the proposed nominee that is required to be disclosed in a proxy statement or other filings in a contested election pursuant to Section 14(a) under the Exchange Act, information regarding the proposed nominee’s indirect and direct interests in shares of the Company’s common stock, and a completed and signed questionnaire, representation and agreement of the proposed nominee. Our bylaws also specify further requirements as to the form and content of a stockholder’s notice. We recommend that any stockholder wishing to make a nomination for director review a copy of our bylaws, as amended and restated to date, which is available, without charge, from our Corporate Secretary, at 58585959 Horton Street, Suite 210,300, Emeryville, CA 94608.

In addition to satisfying the foregoing requirements under our bylaws, to comply with the SEC’s universal proxy rules (once they become effective), stockholders who wish to solicit proxies in support of director nominees other than our proposed nominees must provide notice that sets forth the information required by Rule 14a-19 under the Exchange Act no later than 60 calendar days prior to the one-year anniversary of the preceding year’s annual meeting.
Board Diversity

Our nominating and corporate governance committee is responsible for reviewing with the boardBoard of directors,Directors, on an annual basis, the appropriate characteristics, skills and experience required for the boardBoard of directorsDirectors as a whole and its individual members. In evaluating the suitability of individual candidates (both new candidates and current members), the nominating and corporate governance committee, in recommending candidates for election, and the boardBoard of directors,Directors, in approving (and, in the case of vacancies, appointing) such candidates, may take into account many factors, including but not limited to the following:

personal and professional integrity;

ethics and values;

practical and mature business judgment;

experience in corporate management, such as serving as an officer or former officer of a publicly held company;

professional and academic experience in the industries in which we compete;

relevant to our industry;

experience as a board member or executive officer of another publicly held company;

experience in finance and accounting and / or executive compensation practices;

diversity of expertise and experience in substantive matters pertaining to our business relative to other board members;

geographic background, gender, age and ethnicity; and

potential or actual conflicts of interest; and

interest.
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practical and mature business judgment.

Currently, our boardBoard of directorsDirectors evaluates each individual in the context of the boardBoard of directorsDirectors as a whole, with the objective of assembling a group that can best maximize the success of the business and represent stockholder interests through the exercise of sound judgment using its diversity of experience in these various areas.

Board Diversity Matrix
The table below provides certain highlights of the composition of our Board members as of April 28, 2022, according to their self-identification within the categories established pursuant to Nasdaq Rule 5605(f):
Board Diversity Matrix (As of April 20, 2022)
​​
 
​​
 
Number of Directors
​​
7
​​
 
Part I: Gender Identity
​​
Female
​​
Male
Directors
​​
3
​​
4
Part II: Demographic Background
​​
 
​​
 
Asian
​​
1
​​
1
White
​​
2
​​
3
Meetings of the Board of Directors, Board and Committee Member Attendance and Annual Meeting Attendance

During 2018,the year ended December 31, 2021, (i) our boardBoard of directorsDirectors met seventhirteen (13) times, the(i) our audit committee met twofour (4) times, the(iii) our compensation committee met threefour (4) times, and the(iv) our nominating and corporate governance committee met zero times. During 2018,three (3) times and (v) each boardmember of directors member, except for Judith Li and Peter Svennilson,the Board of Directors attended at least 75% of the meetings of the boardBoard of directorsDirectors and of the committees of the boardBoard of directorsDirectors on which he or she served, in each case, to the extent appointed as a board of directors member at the relevant time of each meeting.served. We encourage all of our directors and nominees for director to attend our annual meeting of stockholders.

Stockholder Communications with the Board of Directors

Should stockholders wish to communicate with the boardour Board of directorsDirectors or any specified individual directors,director, such correspondence should be sent to the attention of the Corporate Secretary, at 58585959 Horton Street, Suite 210,300, Emeryville, CA 94608. The Corporate Secretary will forward the communication to the boardBoard of directors.

Directors.

Compensation Committee Interlocks and Insider Participation

During

From January 1 to June 1, 2021, the year ended December 31, 2018, Thomas Woiwode, Ph.D., Richard Heyman, Ph.D., Steve Krognes and Patrick Mahaffy (a former membermembers of our boardcompensation committee were Dr. Woiwode, Dr. Heyman and Mr. Krognes. Following Dr. Woiwode’s resignation from the Board, effective as of directors) servedJune 1, 2021, Dr. Agarwal was appointed to fill Dr. Woiwode’s seat on the compensation committee. Dr. Heyman. Dr. Agarwal and Mr. Krognes continue to serve as members of our compensation committee. Dr. Heyman serves as the chairperson of the committee. None of the members of ourthe compensation committee during 2018 nor any of the current members of the committee has at any time been one of our officers or employees. None of our executive officers currently serves or in the past fiscal year has served, as a member of the boardBoard of directorsDirectors or compensation committee of any entity that has one or more executive officers on our Board of Directors or compensation committee. During 2021, Dr. Allen, our President and Chief Executive Officer, served on the board of directors and compensation committee of Epizyme until his resignation in November 2021. During such time, Dr. Agarwal, served as the Executive Vice President and Chief Medical and Development Officer of Epizyme.
Derivatives Trading, Hedging, and Pledging Policies
Our Insider Trading Compliance Policy prohibits our officers, directors, employees and specified consultants (and members of their immediate family or compensation committee.household) from engaging in hedging transactions involving our equity securities, including but not limited to zero-cost collars and forward sale contracts, and from engaging in short sales or transactions in puts, calls, or other derivative securities involving our equity securities. In addition, our Insider Trading Compliance Policy prohibits these individuals from pledging our securities as collateral to secure loans. This prohibition means, among other things, that these individuals may not hold our securities in a “margin account,” which would allow the individual to borrow against their holdings to buy securities.
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CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS

The following is a description of transactions since January 1, 20182021 to which we have been a party, in which the amount involved exceeds $120,000, and in which any of our directors, executive officers or beneficial owners of more than 5% of our capital stock, or an affiliate or immediate family member thereof, had or will have a direct or indirect material interest.

Sales and Purchases of Securities

Series C Convertible Preferred Stock

PIPE Financing

In June, July and August 2018,September 2021, we issued an aggregate of 1,611,603completed a private placement transaction in which we sold 5,000,000 shares of our Series C convertible preferredcommon stock at a price of $11.00 per share pursuant to a securities purchase agreement entered into on September 16, 2021 (the “2021 PIPE Financing”). As a result of $13.04 (in each case,the 2021 PIPE Financing, we received aggregate net proceeds of approximately $52.7 million after giving effect todeducting placement agent commissions and offering expenses payable by the1-for-6.9 reverse stock split Company. In connection with the issuance and sale of our outstanding capitalcommon stock in the 2021 PIPE Financing, on October 15, 2021, we effectedfiled a registration statement on September 20, 2018) for aggregate proceeds to usForm S-3 with the SEC registering the resale of approximately $21.0 million. Of these shares, we sold 153,360all shares of Series C convertible preferredour common stock to entities affiliated with Redmile Group, which beneficially ownedissued in the 2021 PIPE Financing.
The following table includes information on (i) the beneficial owners of more than 5% of our capital stock immediately prior to and followingthat participated in the transaction.

Participation in IPO

Certain of our stockholders, including entities affiliated with certain of our directors, purchased, and we directed allocations for, an aggregate of approximately $31.0 million2021 PIPE Financing, (ii) number of shares of our common stock that each such beneficial owner purchased in our initial public offering at the public offering2021 PIPE Financing and (iii) the total purchase price and on the same terms as the other purchasers in this offering and not pursuant to anypre-existing contractual rights or obligations.

paid for purchased shares:

Name
​​
Shares of
Common Stock
​​
Total Purchase Price
($)
Entities affiliated with Redmile Group, LLC(1)
​​
909,091
​​
10,000,001
(1)
Entities affiliated with Redmile Group, LLC were the beneficial owners of, in the aggregate, more than 5% of our capital stock prior to the closing of the PIPE Financing.
Director and Executive Officer Compensation

See “Executive Compensation”“Executive Compensation” and “Director Compensation”“Director Compensation” for information regarding compensation of directors and executive officers.

Employment Agreements

We have entered into employment agreements with our executive officers. For more information regarding these agreements, see “Executive“Executive Compensation—Narrative to Summary Compensation Table and Outstanding Equity Awards at 20182021 Fiscal Year End.End.”

Investors’ Rights Agreement

We entered into an amended and restated investors’ rights agreement with the purchasers of our outstanding preferred stock and certain of our other stockholders, including entities with which certain of our directors are affiliated. As of December 31, 2018, the holders of approximately 19.4 million shares of our common stock are entitled to rights with respect to the registration of their shares under the Securities Act.

Indemnification Agreements and Directors’ and Officers’ Liability Insurance

We have entered into indemnification agreements with each of our directors and executive officers. These agreements require us to, among other things, indemnify each director and executive officer to the fullest extent permitted by Delaware law, including indemnification of expenses such as attorneys’ fees, judgments, penalties fines and settlement amounts incurred by the director or executive officer in any action or proceeding, including any action or proceeding by or in right of us, arising out of the person’s services as a director or executive officer. We also have obtained an insurance policy that insures our directors and executive officers against certain liabilities, including liabilities arising under applicable securities laws.

Policies and Procedures for Related PartyPerson Transactions

Our boardBoard of directorsDirectors has adopted a written related person transaction policy setting forth the policies and procedures for the review and approval or ratification of related person transactions. This policy covers, with certain exceptions set forth in Item 404 ofRegulation S-K under the Securities Act, any transaction, arrangement or relationship, or any series of similar transactions, arrangements or relationships in which we were or are to be a participant, where the amount involved exceeds $120,000 (or the transaction is otherwise material based on the facts and circumstances) and a related person had or will have a direct or indirect material interest, including without limitation purchases of goods or services by or from the related person or entities in which the related person has a material interest, indebtedness, guarantees of indebtedness and employment by us of a related person. In reviewing and approving any such transactions, our audit committee is tasked to consider all relevant
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facts and circumstances, including but not limited to whether the transaction is on terms comparable to those that could be obtained in an arm’s length transaction with an unrelated third party and the extent of the related person’s interest in the transaction. AllEach transaction required to be reported under Item 404(a) of Regulation S-K since the transactionsbeginning of last fiscal year was entered into in compliance with our related person transaction policy described in this section occurred prior to the adoption of this policy.above.
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EXECUTIVE OFFICERS

The following table sets forth certain information about our executive officers of Gritstone are set forth below withand their respective ages as of April 22, 2019:

20, 2022:
Name
​​
Age
​​
Position(s)

Name

Age

Position(s)

Andrew Allen, M.D., Ph.D.

​​52
55
​​
President, Chief Executive Officer and Director

Jean-Marc Bellemin

Celia Economides
​​47
42
​​
Executive Vice President and Chief Financial Officer

Matthew Hawryluk, Ph.D.

​​41
44
​​
Executive Vice President, Chief Business Officer

Erin Jones

​​47
50
​​
Executive Vice President Global Head of Regulatory Affairs and Quality AssuranceChief Operating Officer

Karin Jooss, Ph.D.

​​54
57
​​
Executive Vice President and Head of Research Chief Scientific Officerand Development

Raphaël Rousseau, M.D., Ph.D.

Rahsaan Thompson
​​50
51
​​
Executive Vice President Chief Medical Officer

Roman Yelensky, Ph.D.

40Executive Vice President, Chief Technology Officerand General Counsel

Executive Officers

The following biographical information is furnished with regardrespect to our executive officers (except foras of as of April 20, 2022. For the biography of Dr. Allen, whose biographical information appears above under “Nomineessee “Proposal No.1: Election of Directors— Nominees for Election to a Three-Year Term Expiring at the 20222025 Annual Meeting of Stockholders”) as of April 22, 2019:

Jean-Marc BelleminStockholders”.

Celia Economides has served as our Executive Vice President of Finance and Chief Financial Officer since January 2018.June 2021. Prior to Gritstone, from January 2008 to December 2017, Mr. BelleminMs. Economides served as senior vice president, market access, business solutionsSenior Vice President, Strategy and services of ActelionExternal Affairs at Kezar Life Sciences, Inc. (“Kezar”), a public company targeting immune-mediated diseases and cancer. Before joining Kezar in 2019, she served as Vice President, Corporate Affairs at Aurinia Pharmaceuticals, US Inc., or Actelion, a biotechnologypublic company until Actelion was acquired by Johnson & Johnsonthat delivered the first FDA-approved oral treatment (an immunotherapy) for lupus nephritis. Previously, Ms. Economides served as Director of Global Medical Affairs and director of Clinical Operations at BioMarin Pharmaceutical, Inc. after the company’s acquisition of Prosensa Holding N.V., where she led IR and corporate communications. Earlier in 2017. Prior to Actelion, Mr. Bellemin held severalher career, Ms. Economides led investor relations and program development at the Biotechnology Innovation Organization (BIO) and worked at a healthcare-focused hedge fund and in financial leadership roles at Guerbet Group. Mr. Belleminservices focusing on the biotech sector. Ms. Economides received a university degree in economics, a master’s degree in financeB.A. from Université Paris Dauphine, a postgraduate degree in finance and accounting from Université Paris IIPanthéon-AssasMcGill University and an M.B.A.M.P.H. in Health Policy and Management from the ESSEC Business School in Paris, France.

Columbia University.

Matthew Hawryluk, Ph.D. has served as our Executive Vice President and Chief Business Officer since November 2015. Since March 2020, Dr. Hawryluk has served as an Advisory Board Member of PathAI, Inc. Prior to Gritstone, from April 2011 to October 2015, Dr. Hawryluk held positions of increasing responsibility at Foundation Medicine, Inc. (“Foundation Medicine”), or Foundation Medicine,then a public molecular diagnostics company (subsequently acquired by Roche), most recently serving as vice president, corporateVice President, Corporate and business development.Business Development. Previously, he held roles in business development, marketing and product management across multiple divisions of Thermo Fisher Scientific, Inc. Dr. Hawryluk received a B.S. from the University of Notre Dame, a Ph.D. in cell biology and protein biochemistry from the University of Pittsburgh School of Medicine and an M.B.A. at Carnegie Mellon University’s Tepper School of Business as a Swartz Entrepreneurial Fellow.

Erin Jones has served as our Executive Vice President and Chief Operating Officer since March 2021 and, previously, as our Executive Vice President, Global Head of Regulatory Affairs and Quality Assurance sincefrom May 2016.2016 to February 2021. Prior to Gritstone, from July 2014 to April 2016, Mr. Jones served as vice president, global headVice President, Global Head of regulatory affairs, medical writing, pharmacologyRegulatory Affairs, Medical Writing, Pharmacology and toxicologyToxicology at Puma Biotechnology, Inc. (“Puma”), or Puma, a public biopharmaceutical company. Prior to Puma, Mr. Jones served as director, regulatory affairsDirector, Regulatory Affairs at BioMarin Pharmaceutical Inc. from July 2012 to July 2014. Earlier in his career, Mr. Jones held various positions at Genentech, Inc., or Genentech, a private biotechnology corporationcompany and subsidiary of Roche, including headHead of regulatory intelligenceRegulatory Intelligence and leader of the HER Franchise Regulatory Group. Mr. Jones received a B.S. in microbiology and chemistry from the University of Pittsburgh and an M.S. in computer systems from Pennsylvania State University.

Karin Jooss, Ph.D. has served as our Executive Vice President and Head of Research & Development since March 2021. Previously, Dr. Jooss served as our Executive Vice President of Research and Chief Scientific Officer sincefrom April 2016.2016 to March 2021. Prior to Gritstone, from May 2009 to April 2016, Dr. Jooss served as headHead of cancer immuno-therapeuticsCancer Immuno-Therapeutics in the vaccine immuno-therapeutics department at Pfizer, Inc., or Pfizer, a public pharmaceutical company, where she was also a member of the vaccine immuno-therapeutics leadership team and served as head

Head of the immuno-pharmacology team.Immuno-Pharmacology Team. Prior to joining Pfizer, Dr. Jooss served as vice presidentVice President of researchResearch at Cell Genesys, Inc., or (“Cell Genesys,Genesys”) from June 2005 to April 2009, and as senior directorSenior Director of

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research at Cell Genesys from July 2001 to June 2005. She is on the editorial board of Molecular Therapy and the Journal of Gene Medicine and is a member of the Immunology and Educational Committee of the American Society of Gene & Cell Therapy and the Industry Task Force of the Society for Immunotherapy of Cancer. Dr. Jooss has served on the board of directors of Fate Therapeutics, Inc., a publicly traded biopharmaceutical company, since March 2019. Dr. Jooss received her diploma in theoretical medicine from the University of Marburg in Germany, a Ph.D. in molecular biology and immunology from the University of Marburg in Germany and performed postgraduate work in gene therapy and immunology at the University of Pennsylvania.

Raphaël Rousseau, M.D., Ph.D.

Rahsaan Thompsonhas served as our Executive Vice President Chief Medical Officerand General Counsel since April 2017.2020. Previously, Mr. Thompson was the General Counsel for Opiant Pharmaceuticals, Inc., a public pharmaceutical company, where he was responsible for all legal aspects of corporate strategy, intellectual property, transactions, compliance and regulatory matters. Prior to Gritstone, from July 2012 to March 2017, Dr. Rousseauthat, as the Vice President of Law for Actelion Pharmaceuticals (“Actelion”), he led the Actelion Law Department based in San Francisco, California. In this position, Mr. Thompson was responsible for overseeing the law department’s support for the Actelion U.S. business. In earlier years at Actelion, he served as senior group medical directorAssociate General Counsel and global franchise head, pediatrics of Genentech. Before Genentech, Dr. Rousseau was senior medical directorCorporate Secretary, where he led litigation, government investigations and lead of the pediatric global development team at Roche from October 2010 to June 2012, and international medical leader, hematology, at Roche from January 2009 to September 2010.acquisitions. Before joining Roche, Dr. RousseauActelion, he worked for the law firm of Quarles & Brady in Chicago, Illinois. Mr. Thompson was a professor of medical and pediatric oncologythe Associate General Counsel at the Université Claude Bernard in Lyon, France. At the Léon Bérard Comprehensive Cancer Center in Lyon, Dr. Rousseau was head of the pediatric translational research program. Earlier inAbraxis Bioscience, prior to its acquisition by Celgene. Mr. Thompson also served as Corporate Counsel at McKesson Corporation. He began his career he was a clinical fellow at Texas Children’s Cancer Centeras an Assistant District Attorney in the Philadelphia District Attorney’s office. Mr. Thompson obtained his bachelor’s degree from Southern Methodist University and a research fellow at the Center for Cell and Gene Therapy at Baylor College of Medicine in Houston.his law degree from Hofstra University. He received a Ph.D. in therapeutic biotechnologies at the Université Denis Diderot and an M.D. from Université René Descartes, both in Paris. He is board certified in pediatrics and has asub-specialty certification in pediatric hematology-oncology.

Roman Yelensky, Ph.D. has served on various non-profit boards and presently serves on the Oakland Museum of California Board of Directors as our Executive Vice President, Chief Technology Officer since March 2017. He joined Gritstone at its inception in October 2015 as executive vice president of sequencing and bioinformatics. Prior to Gritstone, from July 2010 to September 2015, Dr. Yelensky served as vice president of biomarker and companion diagnostic development at Foundation Medicine. Prior to Foundation Medicine, Dr. Yelensky was a senior scientist in biomarker development at Novartis AG from April 2009 to July 2010. He received a B.A. in computer science from Cornell University, an M.S. in computer science from Stanford University and a Ph.D. in bioinformatics and integrative genomics from theHarvard-MIT Finance Committee Chair. Division of Health Sciences and Technology.

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EXECUTIVE COMPENSATION

This section discusses the material components of the executive compensation program for our “named executive officers” in the “Summary Compensation Table” below. In 2018, ourOur named executive officers in 2021, and their positions, were as follows:

Andrew Allen, M.D., Ph.D., President and Chief Executive Officer;

Jean-Marc Bellemin,Karin Jooss, Ph.D., Executive Vice President and Head of Research & Development

Erin Jones, Executive Vice President and Chief Financial Officer;

Operating Officer

Roman Yelensky, Ph.D., Executive Vice President and Chief Technology Officer; and

Jayant Aphale, Ph.D., Former Executive Vice President of Technical Operations.

Dr. Aphale ceased serving as our Executive Vice President of Technical Operations and began serving as a Special Advisor to the Chief Executive Officer on December 7, 2018. Dr. Aphale terminated employment with us on March 12, 2019. As an “emerging growth company” as defined in the JOBS Act, we are not required to include a Compensation Discussion and Analysis section and have elected to comply with the scaled disclosure requirements applicable to emerging growth companies.

Summary Compensation Table

The following table provides information regarding thecash and equity compensation of our named executive officers duringfor the fiscal years ended December 31, 2018 and 2017.

Name and Principal Position

 Year  Salary ($)  Bonus($)(1)  Option
Awards
($)(2)		  Non-Equity
Incentive Plan
Compensation
($)(3)		  All Other
Compensation
($)(4)		  Total ($) 
Andrew Allen, M.D., Ph.D.  2018��  475,250    921,566   250,100   5,500   1,652,416 
President and Chief Executive Officer  2017   435,625    —     156,825   —     592,450 
Jean-Marc Bellemin(5)
EVP and Chief Financial Officer		  2018   359,470   25,000   704,908   152,420   3,766   1,245,564 
Roman Yelensky, Ph.D.
EVP and Chief Technology Officer		  2018   341,667    470,270   125,861   5,256   943,054 

Jayant Aphale, Ph.D.(6)

Former EVP of Technical Operations

  2018   274,318   119,000   990,123    515,232   1,898,673 

presented.
Name and Principal Position
​​
Year
​​
Salary
($)
​​
Option
Awards ($)(1)
​​
Stock
Awards
($)(2)
​​
Non-Equity
Incentive Plan
Compensation
($)(3)
​​
All Other
Compensation
($)(4)
​​
Total
($)
Andrew Allen, M.D., Ph.D.
President and Chief
Executive Officer
​​
2021
​​
589,417
​​
2,397,735
​​
241,818
​​
309,444
​​
5,800
​​
3,544,214
​
2020
​​
569,167
​​
1,381,806
​​
—
​​
298,812
​​
5,700
​​
2,255,485
Karin Jooss, Ph.D.
Executive Vice President and
Head of Research &
Development
​​
2021
​​
​451,697
​​
826,289
​​
139,974
​​
199,713
​​
​6,618
​​
1,624,291
​
2020
​​
407,383
​​
552,457
​​
—
​​
171,101
​​
10,411
​​
1,141,352
Erin Jones
Executive Vice President and
Chief Operating Officer
​​
2021
​​
417,566
​​
826,310
​​
129,940
​​
175,378
​​
4,794
​​
1,553,988
​
2020
​​
375,314
​​
703,162
​​
—
​​
157,632
​​
4,438
​​
1,240,546
(1)

Mr. Bellemin received a $25,000 sign on bonus in connection with the commencement of his employment with us. Dr. Aphale’s 2018 bonus was fixed at the amount shown irrespective of performance as part of a Transition and Separation Agreement entered into with Dr. Aphale in connection with his transition and separation from employment with us. For additional details, see the description of the Transition and Separation Agreement below under the heading “Transition and Separation Agreement”.

(2)

The amounts included in this column reflect the aggregate grant date fair value and, in the case of certain of Dr. Aphale’s stockall options incremental fair value, of stock options computedgranted during 2021 that were calculated in accordance with the provisions of Accounting Standards Codification (ASC) 718, Compensation – Stock Compensation. The assumptions that we used to calculate these amounts are discussed in Note 10 to ourthe consolidated financial statements for the year ended December 31, 2018 included in our Annual Report on Form10-K for the fiscal year ended December 31, 2018. 2021.

(2)
The incrementalamounts included in this column reflect the aggregate grant date fair value included for Dr. Aphale of $388,258 related toall restricted stock units granted during 2021 that were calculated based on the deemed modificationclosing market price of hisour common stock options permitting them to remain outstanding and continue to vest from December 7, 2018 to March 12, 2019 during which time Dr. Aphale did not provide substantial services to us.

on the date of grant.
(3)

The amounts included in this column reflect bonus payments earned based on performance pursuant to our annual cash bonus program.

(4)

Other than for Dr. Aphale,Jooss, the amount reported represents 401(k) planamounts included in this column represent matching contributions made by us. The amountunder our 401(k) plan. For Dr. Jooss, the amounts reported for Dr. Aphale includes2021 and 2020 represent, respectively, (i) $5,122$5,225 and $5,327 of 401(k) plan matching contributions made by us, (ii) $110,225 of relocation expenses reimbursed by us, (iii) $49,167$962 and $3,511 paid by us to Dr. AphaleJoss to reimburse her for commuting expenses, and (iii) $431 and $1,573 paid by us to Dr. Jooss to reimburse taxes she incurred in connection with his relocation reimbursement, (iv) $255,000 of accrued severance, (v) $18,118 of accrued post-termination healthcare continuation coverage (vi) $72,661 of accrued salary and vacation through his termination date, and (vii) $4,939 of accrued healthcare coverage through his termination date.

her commuting expense reimbursement.
(5)

Mr. Bellemin was appointed as our Chief Financial Officer on January 5, 2018.

(6)

Dr. Aphale ceased serving as our Executive Vice President of Technical Operations and began serving as a Special Advisor to the Chief Executive Officer on December 7, 2018. Dr. Aphale terminated employment with us on effective March 12, 2019. For additional details, see the description of the Transition and Separation Agreement below under the heading “Transition and Separation Agreement”.

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Outstanding Equity Awards at 2021 FiscalYear-End 2018

Year End

The following table provides information regarding equity awards held by our named executive officers as of December 31, 2018.

     Option Awards  Stock Awards 

Name

 Vesting
Commencement
Date(1)		  Number of
Securities
Underlying
Unexercised
Options (#)
Exercisable		  Number of
Securities
Underlying
Unexercised
Options (#)
Unexercisable		  Option
Exercise
Price ($)		  Option
Expiration
Date		  Number of
Shares or
Units of
Stock That
Have Not
Vested (#)		  Market
Value of
Shares or
Units of
Stock That
Have Not
Vested ($)(2)		 

Andrew Allen, M.D., Ph.D.

  08/01/15(3)   —     —     —     —     241,546   3,731,886 
  09/27/18(4)   8,876   133,152   9.59   08/06/28   —     —   

Jean-Marc Bellemin

  02/07/18   —     166,542   3.17   02/06/28   —     —   
  09/27/18(4)   3,215   48,233   9.59   08/06/28   —     —   

Roman Yelensky, Ph.D.

  10/27/15(3)   —     —     —     —     26,854(7)   414,894 
  02/08/17   22,191   28,533   0.76   02/07/27   —     —   
  09/27/18(4)   4,528   67,935   9.59   08/06/28   —     —   

Jayant Aphale, Ph.D.(5)

  03/12/18   —     72,463   9.59   08/06/28   —     —   
  09/27/18(4)   1,222   18,342   9.59   08/06/28   —     —   

2021.
 
​​
Option Awards
​​
Stock Awards
Name
​​
Vesting
Start
Date(1)
​​
Number of
Securities
Underlying
Unexercised
Options
(#)
Exercisable
​​
Number of
Shares
Underlying
Unexercised
Options
(#)
Unexercisable
​​
Exercise
Price
of Option
Awards
($)
​​
Option
Expiration
Date
​​
Number of
Shares of
Stock That
Have Not
Vested
(#)
​​
Market
Value of
Shares or
Units of
Stock That
Have Not
Vested
($)(2)
Andrew Allen, M.D., Ph.D.
​​
01/07/21
​​
—
​​
—
​​
—
​​
—
​​
48,200
​​
619,852
​
03/08/21
​​
54,375
​​
235,625
​​
13.87
​​
03/07/31
​​
—
​​
—
​
03/01/20
​​
120,312
​​
154,688
​​
8.91
​​
02/24/30
​​
—
​​
—
​
03/01/19
​​
123,750
​​
56,250
​​
12.02
​​
02/12/29
​​
—
​​
—
​
09/27/18
​​
115,397
​​
26,631
​​
9.59
​​
08/06/28
​​
—
​​
—
Karin Jooss, Ph.D.
​​
01/07/21
​​
—
​​
—
​​
—
​​
—
​​
27,900
​​
358,794
​
03/08/21
​​
18,750
​​
81,250
​​
13.87
​​
03/07/31
​​
—
​​
—
​
03/01/20
​​
48,125
​​
61,875
​​
8.91
​​
02/24/30
​​
—
​​
—
​
03/01/19
​​
45,375
​​
20,625
​​
12.02
​​
02/12/29
​​
—
​​
—
​
09/27/18
​​
41,801
​​
9,647
​​
9.59
​​
08/06/28
​​
—
​​
—
Erin Jones
​​
01/07/21
​​
—
​​
—
​​
—
​​
—
​​
25,900
​​
333,074
​
03/08/21
​​
18,750
​​
81,250
​​
13.87
​​
03/07/31
​​
—
​​
—
​
03/01/20
​​
61,250
​​
78,750
​​
8.91
​​
02/24/30
​​
—
​​
—
​
03/01/19
​​
45,375
​​
20,625
​​
12.02
​​
02/12/29
​​
—
​​
—
​
09/27/18
​​
23,550
​​
5,435
​​
9.59
​​
08/06/28
​​
—
​​
—
​
03/01/17(3)
​​
14,492
​​
—
​​
0.76
​​
02/07/27
​​
—
​​
—
​
05/09/16(3)
​​
28,971
​​
—
​​
0.35
​​
05/17/26
​​
—
​​
—
(1)

Except as otherwise noted, stock options vest as to 25% of the shares initially underlying the option on the first anniversary of the vesting commencement date and become exercisable as to 1/48th of the shares initially subject tounderlying the option on each monthly anniversary of the vesting commencementstart date, thereafter, subject to continued service to us, and restricted stock units vest in two equal installments on each anniversary of the vesting start date, subject to continued service to us.

(2)

Amounts reported calculated based onby multiplying $12.86, the closing trading price of our common stock as reported on the Nasdaq Global Select Market, of $15.45 per share on December 31, 2018.

2021, times the number of outstanding restricted stock units.
(3)

Restricted stock vests, and our right of repurchase thereon lapses, in substantially equal monthly installments through the fourth anniversary of the vesting commencement date, subject to the executive’s continued service with us.

Fully vested.
(4)

The option vests in respect of 1/48th of the shares initially subject to the option on each monthly anniversary of the vesting commencement date, subject to continued service to us.

(5)

Dr. Aphale terminated employment with us on March 12, 2019 and all unvested options held by him as of that date were forfeited. For additional details, see the description of the Transition and Separation Agreement below under the heading “Transition and Separation Agreement”.

Narrative to Summary Compensation Table and Outstanding Equity Awards at 20182021 Fiscal Year End

2018

2021 Salaries

Our named executive officers each receive a base salary to compensate them for services rendered to our company.the Company. The base salary payable to each named executive officer is intended to provide a fixed component of compensation reflecting the executive’s skill set, experience, role and responsibilities.

For fiscal year 2018,

Effective March 1, 2021, Dr. Allen’s annual base salary was $500,000, Mr. Bellemin’s$592,300, Dr. Jooss’ base salary was $365,000, Dr. Aphale’s$460,000, and Mr. Jones’ base salary was $340,000 and Dr. Yelensky’s$425,000. The base salary was $350,000. The annual base salaries of Dr. Allen and Dr. Yelensky were increased 14% and 17%, respectively as compared to their 2017 salaries.

2018amounts actually paid in fiscal year 2021 are set forth above in the Summary Compensation Table in the column titled “Salary.”

2021 Bonuses

We maintain an annual performance-based cash bonus program in which each of our named executive officers participated in 2018.2021. Each named executive officer’s target bonus is expressed as a percentage of base salary which can be achieved by meeting certain corporate goals established by theour board of directors.directors and subject to discretion. The 20182021 annual bonuses for Dr. Allen, Dr. Jooss and Mr. Bellemin, Dr. Aphale and Dr. YelenskyJones were targeted at 50%, 35%, 35%40% and 35%40% of their respective base salaries.
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In early 2019, the2022, our board of directors reviewed and approved the achievement of our 20182021 corporate goals at 105.25%105%. Based on this level of achievement, our named executive officers were paid bonuses at 105.25%105% of their targeted amounts, except for Dr. Aphale, whose bonus was paid at 100% pursuant to the Transition and Separation Agreement entered into between us and Dr. Aphale. For additional details, see the description of the Transition and Separation Agreement below under the heading “Transition and Separation Agreement”.

amounts.

The annual cash bonuses paid to each named executive officer for 20182021 performance are set forth above in the Summary Compensation Table in the column titled“Non-Equity “Non-Equity Incentive Plan Compensation.”

2018

2021 Equity Compensation

We use equity awards to motivate and reward our executive officers for long-term corporate performance based on the value of the Company’s common stock and, thereby, align the interests of our executive officers with those of our stockholders. We believe equity provides appropriate long-term incentive and retention of our executive officers.
In connection with our initial public offering, we adopted and our stockholders approved, the 2018 Incentive Award Plan (the “2018 Plan”) in order to facilitate the grant of cash and equity incentives to directors, employees (including our named executive officers) and consultants of the Company and to enable us to obtain and retain services of these individuals, which is essential to our long-term success.
On August 7, 2018,March 8, 2021, our board of directors granted Dr. Allen, Dr. Jooss and Mr. Bellemin, Dr. Yelensky and Dr. AphaleJones an option to purchase 142,028, 51,448, 72,463290,000, 100,000 and 19,564100,000 shares of our common stock, respectively (on a split-adjusted basis).respectively. Each option hadhas an exercise price per share equal to $9.59,$13.87, which was the fair market valueclosing trading price of our common stock on the date of grant (on a split-adjusted basis), as determined by our board of directors. The options were intended to incentivize our named executive officers to complete the initial public offering of our common stock and did not commence vesting until September 27, 2018, the effective date of the registration statement for the initial public offering of our common stock. grant.
Each option vests as to 1/48th of the initial number of shares underlying the option on each monthly anniversary of September 27, 2018,March 8, 2021, subject to the named executive officer’s continued service to us.

Also on August

On January 7, 2018, in accordance with his offer letter with us dated February 2018, the2021, our board of directors granted Dr. Aphale an optionAllen, Dr. Jooss and Mr. Jones, 48,200, 27,900 and 25, 900 restricted stock units, respectively. Each restricted stock unit constitutes the right to purchase 72,463 shares of our common stock (on a split-adjusted basis) pursuant to our 2015 Equity Incentive Plan. The option has an exercise price perbe issued one share of $9.59, which wasstock upon vesting. The restricted stock units vest in equal installments on each of the fair market valuefirst two anniversaries of our common stock on the date of grant, (on a split-adjusted basis), as determined by our board of directors. The option was scheduled to vest as to 25% of the initial shares underlying the option on the first anniversary of Dr. Aphale’s commencement of employment with us (March 12, 2018) and as to 1/48th of the initial shares underlying the option on each monthly anniversary of his commencement date thereafter. Dr. Aphale terminated employment with us on March 12, 2019 after 25% of the shares underlying the option had vested. The unvested portion of each of his options was forfeited upon his termination of employment. For additional details, see the description of the Transition and Separation Agreement below under the heading “Transition and Separation Agreement”.

In February 2018, in accordance with his offer letter with us dated December 2017, the board of directors granted Mr. Bellemin an option to purchase 166,542 shares of our common stock (on a split-adjusted basis) pursuant to our 2015 Equity Incentive Plan. Mr. Bellemin’s option grant vests as to 25% of the shares initially underlying the option on the first anniversary of Mr. Bellemin’s employment commencement date (January 5, 2018), and as to 1/48th of the shares initially underlying the option on each monthly anniversary thereafter, subject to Mr. Bellemin’s continued serviceservices to the Company on each applicable vesting date.

us.

Options and restricted stock units granted to Dr. Allen, Dr. Jooss and Mr. Bellemin and Dr. YelenskyJones are subject to the accelerated vesting provisions in their employment agreements described below under “Executive Compensation Arrangements.”

In connection with our IPO, we adopted our 2018 Incentive Award Plan, referred to below as the 2018 Plan, in order to facilitate the grant of cash and equity incentives to directors, employees (including our named executive officers) and consultants of our company and certain of its affiliates and to enable us to obtain and retain services of these individuals, which is essential to our long-term success. The 2018 Plan became effective on the day prior to the first public trading date of our common stock, and since then no further grants have been or will be made under our 2015 Equity Incentive Plan.

“Executive Compensation Arrangements

.”

Executive Compensation Arrangements
Employment Agreements

In September 2018, we entered into new employment agreements with each of our named executive officers, which superseded in their entirety their prior offer letters with us. Each employment agreement provides that the executive’s employment with us isat-will, and provides for an annual base salary and target annual bonus (expressed as a percentage of base salary), as well as severance and change in control benefits, as described below.

Under Dr. Allen’s employment agreement, if he is terminated without “cause” or resigns for “good reason” (as each is defined in his employment agreement), he will be eligible to receive the following: (i) an amount equal to the sum of his base salary and target annual bonus; and (ii) payment or reimbursement of up to 12 months of healthcare continuation coverage. In addition, if Dr. Allen is terminated without cause or resigns for good reason during the period commencing three months before and ending 12 months after a change in control of the Company, he will be eligible to receive the following: (i) an amount equal to the sum of (A) 150% of his base salary and (B) his target annual bonus; (ii) payment or reimbursement of up to 18 months of healthcare continuation coverage; and (iii) full vesting acceleration of all then-outstanding equity awards. The foregoing severance benefits are subject to Dr. Allen’s execution andnon-revocation of a general release of claims against the Company.

Under each of Dr. Jooss’ and Mr. Bellemin’s and Dr. Yelensky’sJones’s employment agreements, if either is terminated without “cause” or resigns for “good reason” (as each is defined in their respective employment agreements), other than in connection with a change in control as described below, the employment agreement), heexecutive will be eligible to receive the following: (i) an amount equal to the sum of (A) 75% of histhe executive’s base salary and (B) histhe executive’s target annual bonus; and (ii) payment or reimbursement of up to nine months of healthcare continuation coverage. In addition, if either is terminated without cause or resigns for good reason during the period commencing three months before and ending 12 months after a change in control of the Company, hethe executive will be eligible to receive the following: (i) an amount equal to the sum of histhe executive’s base salary and target annual bonus; (ii) payment or reimbursement of up to 12 months of healthcare continuation coverage; and (iii) full vesting
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acceleration of all then-outstanding equity awards. The foregoing severance benefits are subject to the executive’s execution andnon-revocation of a general release of claims against the Company.

Transition and Separation Agreement

In connection with his transition from serving as our Executive Vice President of Technical Operations to the role as Special Advisor to the Chief Executive Officer on December 7, 2018 and the termination of his

employment with us on March 12, 2019, we entered into a Transition and Separation Agreement with Dr. Aphale. Under the Transition and Separation Agreement, Dr. Aphale’s bonus for 2018 was fixed at 100% of his target bonus amount, we continued to pay his base salary and he continued to be eligible for benefits under our plans through his termination date. Pursuant to the Transition and Separation Agreement, in connection with the termination of his employment on March 12, 2019, and in exchange for a release of claims against the Company, he received (i) cash severance of $374,000 (an amount equal to nine months of his base salary and his target bonus) and (ii) payment or reimbursement of up to nine months of healthcare continuation coverage.

Other Elements of Compensation

Retirement Savings and Health and Welfare Benefits

We maintain a 401(k) retirement savings plan for our employees, including our named executive officers, who satisfy certain eligibility requirements. Our named executive officers are eligible to participate in the 401(k) plan on the same terms as other full-time employees. Currently, we may match (in our discretion) contributions made by participants in the 401(k) plan in the amount equal to 50% of up to 4% of the participant’s eligible compensation contributed to the plan, not to exceed 2% of a participant’s eligible compensation. We believe that providing a vehicle fortax-deferred retirement savings though our 401(k) plan adds to the overall desirability of our executive compensation package and further incentivizes our employees, including our named executive officers, in accordance with our compensation policies.

All of our full-time employees, including our named executive officers, are eligible to participate in our health and welfare plans, including medical, dental and vision benefits; medical and dependent care flexible spending accounts; short-term and long-term disability insurance; and life and AD&D insurance.

Perquisites and Other Personal Benefits

We provide limited perquisites to our named executive officers when our compensation committee determines that such perquisites are necessary or advisable to fairly compensate or incentivize our employees. In 2018 we reimbursed relocation expenses for Dr. Aphale’s relocation to our headquarters as well as reimbursement of taxes incurred in connection with such relocation expenses.

Equity Compensation Plan Information

The following table provides certain information as of December 31, 2018,2021, with respect to all of our equity compensation plans in effect on that date:

Plan Category

  Number of
Securities to
be Issued
Upon
Exercise of
Outstanding
Options,
Warrants
and Rights
(a)		   Weighted-
Average
Exercise
Price of
Outstanding
Options,
Warrants
and Rights
(b)		   Number of
Securities
Remaining
Available for
Future
Issuance
Under  Equity
Compensation
Plans
(Excluding
Securities
Reflected in
Column (a))
(c)(3)		 

Equity Compensation Plans Approved by Stockholders(1)(2)(3)

   2,429,859   $5.31    2,977,444 

Equity Compensation Plans Not Approved by Stockholders

   —      —      —   
  

 

 

   

 

 

   

 

 

 

Total

   2,429,859   $5.31    2,977,444 
  

 

 

   

 

 

   

 

 

 

Plan Category
​​
Securities
Subject
to the
Outstanding
Options,
RSUs,
Warrants
and Rights
(a)
​​
Weighted-
Average
Exercise
Price of
Outstanding
Options,
Warrants
and Rights
(b)
​​
Securities
Available for
Future
Issuance
(Excluding
Securities
Reflected in
Column (a))
(c)
Equity Compensation Plans Approved by Stockholders(1)(2)(3)
​​
5,214,135(5)
​​
$9.93
​​
4,199,569(6)
Equity Compensation Plans Not Approved by Stockholders(4)
​​
602,000
​​
$8.96
​​
188,400
Total
​​
5,816,135
​​
$9.82
​​
4,387,969
(1)

Consists of the Gritstone Oncology, Inc.our 2018 Incentive Award Plan, 2018 Employee Stock Purchase Plan and 2015 Equity Incentive Plan, as amended.

Plan.

(2)

The 2018 Equity Incentive Award Plan contains an “evergreen” provision, pursuant to which the number of shares of common stock reserved for issuance pursuant to awards under such plan shall be increased on the first day of each year beginning in 2019 and ending in 2028 equal to the lesser of (A) four percent (4%) of the shares of stock outstanding (on an as converted basis) on the last day of the immediately preceding fiscal year and (B) such smaller number of shares of stock as determined by our board of directors; provided, however, that no more than 45,000,000 shares of stock may be issued upon the exercise of incentive stock options.

(3)

The 2018 Employee Stock Purchase Plan contains an “evergreen” provision, pursuant to which the number of shares of common stock reserved for issuance under such plan shall be increased on the first day of each year beginning in 2019 and ending in 2028 equal to the lesser of (A) one percent (1%) of the shares of stock outstanding (on an as converted basis) on the last day of the immediately preceding fiscal year and (B) such smaller number of shares of stock as determined by our board of directors; provided, however, no more than 5,000,000 shares of stock may be issued under the 2018 Employee Stock Purchase Plan.

(4)
Consists of our 2021 Employment Inducement Incentive Award Plan (“2021 Plan”). Our 2021 Plan was adopted by the Board pursuant to Nasdaq Listing Rule 5635(c)(4). All awards granted under the 2021 Plan are intended to constitute “employment inducement awards” under Nasdaq Listing Rule 5635(c)(4), and, therefore, the 2021 Plan is exempt from the Nasdaq Listing Rules regarding shareholder approval of stock option and stock purchase plans. A total of 790,400 shares (“the 2021 Plan Share Limit”) of our common stock were initially reserved for issuance under the 2021 Plan. The 2021 Plan provides that the 2021 Plan Share Limit may be increased by the Board without the stockholder approval.
(5)
Consists of 4,505,335 shares of common stock underlying outstanding options and 708,800 share of common stock subject to the outstanding unvested restricted stock units.
(6)
Includes 3,270,787 and 928,782 shares that were available for future issuance as of December 31, 2021 under our 2018 Incentive Award Plan and 2018 Employee Stock Purchase Plan, respectively.
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DIRECTOR COMPENSATION

Pursuant to the

Non-Employee Director Compensation Program
Our Non-Employee Director Compensation Program, which we adopted in connection withas amended and restated on March 8, 2021, sets forth cash and equity compensation provided to our IPO,non-employee directors.
Cash Compensation
As of March 8, 2021, ournon-employee directors receive cash compensation as follows:

Eachnon-employee director receives anare entitled to the following (i) annual cash retainer for their service on the Board and (ii) fees for their service on the committees of the Board:

Each Non-Employee Director
​​
$40,000
Non-Executive Chairperson of the Board
​​
$35,000
Audit Committee Chairperson
​​
$15,000
Compensation Committee Chairperson
​​
$10,000
Nominating and Corporate Governance Committee Chairperson
​​
$8,000
Each Audit Committee Member (non-Chairperson)
​​
$7,500
Each Compensation Committee Member (non-Chairperson)
​​
$5,000
Each Nominating and Corporate Governance Committee Member (non-Chairperson)
​​
$4,000
Cash compensation is paid quarterly in arrears promptly following the end of the applicable calendar quarter, but in no event more than 30 days after the end of such quarter. In the event a non-employee director does not serve as a non-employee director, or in the amount of $35,000 per year.

The Independent Chairperson receivesapplicable position(s) described above, for an additionalentire calendar quarter, the annual cash retainer and fees paid to such non-employee director is prorated for the portion of such calendar quarter actually served as a non-employee director, or in such position(s), as applicable.

Equity Compensation
Initial Stock Option Grant
Each non-employee director who is initially elected or appointed to serve on our Board is granted a stock option award under our 2018 Plan (or any other applicable equity incentive plan then-maintained by us) to purchase 38,000 shares of our Common Stock (such initial stock option award, the amount of $30,000 per year.

“Initial Stock Option Grant”).

The chairperson ofInitial Stock Option Grant is automatically granted on the audit committee receives additional annual cash compensation in the amount of $15,000 per year fordate on which such chairperson’snon-employee director commences service on the audit committee. Eachnon-chairperson memberBoard and will vest as to 1/36th of the audit committee receives additional annual cash compensationshares subject thereto on each monthly anniversary of the applicable date of grant such that the shares subject to the Initial Stock Option Grant are fully vested on the third anniversary of the grant, subject to the non-employee director continuing in the amount of $7,500 per year for such member’s service on the audit committee.

Board through each vesting date.

The chairperson of the compensation committee receives additional annual cash compensation in the amount of $10,000 per year for such chairperson’s serviceAnnual Stock Option Grant

Each non-employee director who is serving on the compensation committee. Eachnon-chairperson memberour Board as of the compensation committee receives additional annual cash compensation in the amount of $5,000 per year for such member’s service on the compensation committee.

The chairperson of the nominating and corporate governance committee receives additional annual cash compensation in the amount of $8,000 per year for such chairperson’s service on the nominating and corporate governance committee. Eachnon-chairperson member of the nominating and corporate governance committee receives additional annual cash compensation in the amount of $4,000 per year for such member’s service on the nominating and corporate governance committee.

Under the Director Compensation Program, eachnon-employee director will automatically be granted an option to purchase 15,942 shares of our common stock upon the director’s initial appointment or election to our board of directors, referred to as the Initial Grant, and an option to purchase 7,971 shares of our common stock automatically on the date of each annual stockholder’sshareholder meeting thereafter, referredof the Company (each, an “Annual Meeting”) is granted a stock option award under the 2018 Plan (or any other applicable equity incentive plan then-maintained by us) to aspurchase 19,000 shares of our Common Stock (such stock option award, the “Annual Stock Option Grant”), provided that the number of shares subject to the Annual Grant. Stock Option Grant are prorated for any partial year of service as a non-employee director.

The Initial GrantAnnual Stock Option Award is automatically granted on the date of the applicable Annual Meeting and will vest in substantially equal monthly installments for three years from the date of grant, subject to continued service through each applicable vesting date. The Annual Grant will vestfull on the earlier of (i) the first anniversary of the date of grant orand (ii) immediately prior to the Annual Meeting following the date of grant, subject to the next annual stockholder’s meetingnon-employee director continuing in service on the Board through such vesting date.
General
The per share exercise price of each of the Initial Stock Option Grant and the Annual Stock Option Grant equals the fair market value of a share of our common stock on the date any such option is granted and is determined pursuant to our 2018 Plan (or any other applicable equity incentive plan then-maintained by us to the extent such
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options were granted under such plans). The term of the Initial Stock Option Grant and the Annual Stock Option Grant is ten years from the date the grant. Any unvested asor unexercisable portion of such date, subject to continuedthe Initial Stock Option Grant and the Annual Stock Option Grant at the time of a non-employee director’s termination of service through each applicable vesting date. In February 2019,on our board of directors amended theBoard is forfeited.
No Employee Director Compensation Program
Our employee-directors do not receive any cash or equity compensation for their service on our Board. If an employee director terminates their service with us or our affiliates and remains on the Board, such former employee director will not receive an Initial Stock Option Grant but, to increase the number of shares underlying theextent that they are otherwise eligible, will be eligible to receive, after termination from service with us and our affiliates, an Annual Stock Option Grant to 8,570. All other terms of the Director Compensation Program remain unchanged.

On August 7, 2018, in connection with Steve Krognes’ appointment to our board of directors the preceding month, we granted Mr. Krognes an option to purchase 15,942 shares of our common stock. The option has an exercise per share of $9.59 and vests in equal monthly installments over 4 years.

as described above.

Director Compensation Table

The following table sets forth information regarding equity awards awarded to or cash compensation earned by or paid to ournon-employee directors during 2018:

Name

  Fees Earned
or Paid in
Cash ($)		   Option
Awards
($)(1)		   Total ($) 

Richard Heyman(2)

  $47,000   $—     $47,000 

Steve Krognes(3)

   22,000    103,752    125,752 

Judith Li

   10,750    —    10,750 

Patrick Mahaffy(4)

   16,000    —    16,000 

Nicholas Simon

   10,625    —    10,625 

Peter Svennilson

   10,625    —    10,625 

Tom Woiwode

   12,250    —    12,250 

our fiscal year ended December 31, 2021:
Name
​​
Fees Earned or
Paid in Cash
($)
​​
Option Awards
($)(1)
​​
Total
($)
Richard Heyman, Ph.D.
​​
51,917
​​
116,749
​​
168,666
Judith Li(2)
​​
48,000
​​
116,749
​​
164,749
Elaine Jones, Ph.D.
​​
84,833
​​
116,749
​​
201,582
Steve Krognes
​​
60,000
​​
116,749
​​
176,749
Nicholas Simon(3)
​​
19,792
​​
—
​​
19,792
Thomas Woiwode, Ph.D.(3)
​​
22,500
​​
—
​​
22,500
Shefali Agarwal, M.D., M.P.H.(4)
​​
32,958
​​
222,493
​​
255,451
Naiyer Rizvi, M.D.(4)
​​
32,958
​​
222,493
​​
255,451
(1)

This column reflectsAmounts reflect the aggregate grant date fair value of stock options granted during 20182021 computed in accordance with the provisions of Accounting Standards Codification (ASC) 718, Compensation – Stock Compensation. The assumptions that we used to calculate these amounts are discussed in Note 10 to ourthe financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2018 included in our Annual Report on Form10-K for the year ended December 31, 2018.

(2)

2021. As of December 31, 2018, Dr. Heyman2021, our non-employee directors held 13,017 shares of restricted stock that are subject to repurchase at the original purchase price thereofoptions set forth in the event Dr. Heyman’s service with us terminates prior to vesting. These shares were acquired upon exercisetable below. None of our non-employee directors held any stock options prior to vesting.

awards.
Name
​​
Number of Shares
Underlying
Option Awards
Richard Heyman, Ph.D.
​​
40,070
Judith Li
​​
40,070
Elaine Jones, Ph.D.
​​
47,442
Steve Krognes
​​
56,012
Nicholas Simon
​​
—
Thomas Woiwode, Ph.D.
​​
—
Shefali Agarwal, M.D., M.P.H.
​​
38,937
Naiyer Rizvi, M.D.
​​
60,784
(2)
Ms. Li resigned from our Board, effective as of January 1, 2022.
(3)

AsDr. Woiwode and Mr. Simon resigned from our Board, effective as of December 31, 2018, Mr. Krognes held an option to purchase 15,942 shares of our common stock.

June 1, 2021.
(4)

In May 2018, Mr. Mahaffy resigned fromDrs. Agarwal and Rizvi joined our boardBoard effective as of directors.

June 1, 2021.
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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table presents information as to the beneficial ownership of our common stock as of April 22, 2019March 31, 2022 for:

each person, or group of affiliated persons, known by us to beneficially own more than 5% of our outstanding shares of common stock;

each of our NEOs;

named executive officers;

each of our directors; and

all executive officers and directors as a group.

Beneficial ownership is determined in accordance with the SEC rules of the SEC and generally includes voting or investment power with respect to our securities. Unless otherwise indicated below, to our knowledge, the persons and entities named in the table have sole voting and sole investment power with respect to all shares beneficially owned, subject to community property laws where applicable. Shares of our common stock subject to options that are currently exercisable or exercisable within 60 days of April 22, 2019March 31, 2022 are deemed to be outstanding and to be beneficially owned by the person holding the options for the purpose of computing the percentage ownership of that person but are not treated as outstanding for the purpose of computing the percentage ownership of any other person.

The percentage of shares beneficially owned is computed on the basis of 29,206,40572,779,508 shares of our common stock outstanding as of April 22, 2019. ThisMarch 31, 2022. The table below is based upon information supplied to us by our executive officers, directors and principal stockholders and Schedules 13D and Schedules 13G, if any, filed with the SEC, as well as information provided to us by The Nasdaq Stock Market, LLC.
Unless otherwise indicated, the address of each of the individuals and entities named below is c/o Gritstone Oncology,bio, Inc., 58585959 Horton Street, Suite 210,300, Emeryville, CA 94608.

   Shares of Common Stock Beneficially Owned 

Name of Beneficial Owner

  Common Stock   Securities
Exercisable
Within 60 Days		   Number of
Shares
Beneficially
Owned		   Percent 

5% Stockholders:

        

Entities affiliated with Versant Ventures(1)

   3,102,929    —      3,102,929    10.6% 

The Column Group II, LP(2)

   3,102,934    —      3,102,934    10.6% 

Clarus Lifesciences III, L.P.(3)

   2,567,445    —      2,567,445    8.8% 

FMR LLC(4)

   3,136,236    —      3,136,236    10.7% 

Entities affiliated with Frazier Healthcare(5)

   2,061,762    —      2,061,762    8.6% 

Trinitas Capital G, L.P.(6)

   1,924,711    —      1,924,711    7.1% 

Entities affiliated with Redmile Group, LLC(7)

   2,514,136    —      2,514,136    6.6% 

Named Executive Officers and Directors:

        

Andrew Allen, M.D., Ph.D.(8)

   1,449,275    34,921    1,484,196    5.1% 

Jean-Marc Bellemin

   —      71,683    71,683        * 

Jayant Aphale(9)

   —      20,150    20,150        * 

Roman Yelensky(10)

   143,224    44,735    187,959        * 

Richard Heyman, Ph.D.(11)

   53,323    —      53,323        * 

Steve Krognes

   —      3,326    3,326        * 

Judith Li

   —      —      —          * 

Nicholas Simon(12)

   2,567,445    —      2,567,445    8.8% 

Peter Svennilson(13)

   3,102,934    —      3,102,934    10.6% 

Thomas Woiwode, Ph.D.(14)

   3,102,929    —      3,102,929    10.6% 

All executive officers and directors as a group (13 persons)(15)

   10,894,237    327,512    11,221,749    38.0% 

 
​​
Shares of Common Stock Beneficially Owned
Name of Beneficial Owner
​​
Common Stock
​​
Securities
Exercisable
Within 60 Days
​​
Number of
Shares
Beneficially
Owned
​​
Percent
>5% Stockholders:
​​
 
​​
 
​​
 
​​
 
Entities affiliated with Redmile Group, LLC(1)
​​
3,291,738
​​
4,420,590
​​
7,712,328
​​
9.99%*
Entities affiliated with Avidity Partners Management LP(2)
​​
4,415,000
​​
2,859,971
​​
7,274,971
​​
9.62%*
Named Executive Officers and Directors:
​​
 
​​
 
​​
 
​​
 
Andrew Allen, M.D., Ph.D.(3)
​​
1,463,596
​​
531,858
​​
1,995,454
​​
2.72%
Karin Jooss, Ph.D.(4)
​​
330,116
​​
198,509
​​
528,625
​​
**
Erin Jones(5)
​​
27,643
​​
237,469
​​
265,112
​​
**
Richard Heyman, Ph.D.(6)
​​
53,323
​​
21,070
​​
74,393
​​
**
Elaine Jones, Ph.D.(7)
​​
—
​​
26,671
​​
26,671
​​
**
Steve Krognes(8)
​​
—
​​
36,016
​​
36,016
​​
**
Clare Fisher(9)
​​
—
​​
4,222
​​
4,222
​​
**
Shefali Agarwal, M.D., M.P.H.(10)
​​
—
​​
11,611
​​
11,611
​​
**
Naiyer Rizvi, M.D.(11)
​​
—
​​
31,375
​​
31,375
​​
**
All executive officers and directors as a group (14 persons)(12)
​​
2,049,309
​​
1,262,903
​​
3,312,212
​​
4.47%

*

Beneficial ownership includes certain pre-funded warrants to purchase our common stock (the “Warrants”). Pursuant to the terms of such Warrants, a holder does not have the right to exercise any portion of the Warrant to the extent that, after giving effect to the issuance of our common stock after exercise, such holder would beneficially own more than 9.99% of the number of shares of our common stock outstanding immediately after giving effect to the issuance of shares of our common stock following the exercise of such Warrant.

**
Indicates beneficial ownership of less than 1% of the outstanding shares of our common stock.

(1)

Based solely on ainformation set forth in Schedule 13G13G/A filed with the SEC by Redmile Group, LLC on February 14, 2019 (the “Versant 13G”)2022 with respect to shares of common stock beneficially owned by Redmile Group, LLC on December 31, 20182021, as updated by the following persons and entities: Versant Venture Capital V, L.P. (“VVC V”), Versant Affiliates Fund V, L.P. (“VAF V”), Versant Ophthalmic Affiliates Fund I, L.P. (“VOA”) and Versant Venture Capital V (Canada) LP (“VVC CAN”). Versant Ventures V, LLC (“VV V”) is the sole general partner of VVC V, VAF V and VOA. Samuel D. Colella (“Colella”), William J. Link (“Link”), Bradley Bolzon, Ph.D (“Bolzon”), Kirk G. Nielsen (“Nielsen”), Thomas Woiwode (“Woiwode”) and Robin L. Praeger (“Praeger”) are managing directors of VV V. Versant Ventures VGP-GP (Canada), Inc. (“VV V CAN GP”) is the sole general partner of Versant Ventures V (Canada), L.P. (“VV V CAN”, and, together with VVC V, VV V, VAF V, VOA, VVC CAN, and VV V CAN GP, the “Versant Reporting Persons”). VV V CAN is the sole general partner of VVC CAN. Colella, Link, Bolzon, Praeger, Nielsen and Woiwode are directors of VV V CAN GP. VV V is the sole general partner of VVC V, VAF V and VOA and may be deemed to have voting and investment power over the securities held by VVC V, VAF V and VOA. Colella, Link, Bolzon, Praeger, Nielsen and Woiwode are managing directors of VV V and share voting and dispositive power over the shares held by VVC V, VAF V and VOA and disclaim beneficial ownership of all shares above except to the extent of their pecuniary interest therein. information

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TABLE OF CONTENTS

provided to us by The Nasdaq Stock Market LLC as of March 31, 2022, Redmile Group, LLC’s beneficial ownership of our common stock is comprised of shares of common stock owned by certain private investment vehicles and/or separately managed accounts managed by Redmile Group, LLC, which shares of common stock may be deemed beneficially owned by Redmile Group, LLC as investment manager of such private investment vehicles and/or separately managed accounts. The reported securities may also be deemed beneficially owned by Jeremy C. Green as the principal of Redmile Group, LLC. Each of Redmile Group, LLC and Mr. Green disclaims beneficial ownership of such shares, except to the extent of their pecuniary interest in such shares, if any. Subject to the Beneficial Ownership Blocker (as defined below), Redmile Group, LLC may also be deemed to beneficially own 14,156,300 shares of our common stock issuable upon exercise of certain Warrants. Pursuant to the terms of such Warrants, the entities affiliated with Redmile Group, LLC that hold such Warrants do not have the right to exercise any portion of their Warrants, and any such exercise shall be void ab initio, to the extent that after giving effect to the issuance of our common stock after exercise, the holder of such Warrant(s) (together with its affiliates, and any other persons acting as a group together with the holder or any of its affiliates), would beneficially own in excess of 9.99% (the “Beneficial Ownership Limitation”) of the number of shares of our common stock outstanding immediately after giving effect to the issuance of shares of our common stock following the exercise of such Warrant(s) (the “Beneficial Ownership Blocker”). The number of shares of our common stock shown as beneficially owned by Redmile Group, LLC reflects application of the Beneficial Ownership Limitation as described above, although the Beneficial Ownership Limitation may be changed at a holder’s election upon 61 days’ notice to Gritstone. The address of Redmile Group, LLC and its affiliated entities and persons is One Letterman Drive, Building D, Suite D3-300, San Francisco, California 94129.
(2)
Based solely on the Versant 13G, shares of common stock beneficially owned by the Versant Reporting Persons consists of (i) 2,723,031 shares of common stock held by VVC V, (ii) 207,234 shares of common stock held by VVC CAN, (iii) 90,756 shares of common stock held by VOA, and (iv) 81,908 shares of common stock held by VAF V. The address for each of the Versant Reporting Persons is One Sansome Street, Suite 3630, San Francisco, CA 94104.

(2)

Based solely on ainformation set forth in Schedule 13G filed with the SEC by Avidity Partners Management LP on February 13, 2019 with respect to shares of common stock beneficially owned on December 31, 2018. The Column Group II GP, LP is the general partner of The Column Group II, LP. The managing partners of The Column Group II GP, LP are David Goeddel and Peter Svennilson. The managing partners of The Column Group II GP, LP may be deemed to have voting and investment power with respect to such shares. Messrs. Goeddel and Svennilson disclaim beneficial ownership of all shares above except to the extent of their pecuniary interest therein. The address of the above persons and entities is 1700 Owens Street, Suite 500, San Francisco, California 94158.

(3)

Based solely on a Schedule 13D/A filed with the SEC on January 11, 2019 by the following persons and entities (collectively, the “Reporting Persons”) with respect to shares of common stock beneficially owned as of January 4, 2019: Clarus Lifesciences III, L.P. (the “Fund”); Clarus Ventures III GP, L.P. (“Clarus GP”), which is the sole general partner of the Fund, Blackstone Clarus III L.L.C., which is the sole general partner of Clarus GP, Blackstone Holdings II L.P., which is the sole member of Blackstone Clarus III L.L.C., Blackstone Holdings I/II GP Inc., which is the sole general partner of Blackstone Holdings II L.P., The Blackstone Group L.P., which is the controlling shareholder of Blackstone Holdings I/II GP Inc., and Blackstone Group Management L.L.C. (collectively, with Blackstone Clarus III L.L.C., Blackstone Holdings II L.P., Blackstone Holdings I/II GP Inc. and The Blackstone Group L.P., the “Control Entities”), which is the sole general partner of The Blackstone Group L.P. and which is wholly-owned by Blackstone’s senior managing directors and controlled by its founder, Stephen A. Schwarzman; and Clarus Ventures III, LLC (“Clarus GP LLC”), and Robert Liptak, Nicholas Simon, Nicholas Galakatos, Dennis Henner and Kurt Wheeler (together, the “Managing Directors”, and collectively with Clarus GP LLC, the “Clarus Persons”). The Managing Directors are the members of Clarus GP LLC. Clarus GP LLC is the former general partner of Clarus GP. Each such Reporting Person may be deemed to beneficially own the common stock beneficially owned by the Fund directly or indirectly controlled by it or him, but each of the Reporting Persons expressly disclaims beneficial ownership of such common stock. The address of the principal business office of the Fund, Clarus GP and each of the Clarus Persons is Clarus Ventures, 101 Main Street, Suite 1210, Cambridge, MA 02142. The address of the principal business office of each of the Control Entities and Mr. Schwarzman is c/o The Blackstone Group L.P., 345 Park Avenue, New York, NY 10154.

(4)

Based solely on a Schedule 13G filed with the SEC on February 13, 201914, 2022 by the following persons and entities with respect to shares of our common stock beneficially owned as ofon December 31, 2018,2021, as updated by information provided to Gritstoneus by The Nasdaq Stock Market LLC as of March 31, 2019: FMR2022: Avidity Partners Management LP, Avidity Partners Management (GP) LLC, and

Abigail P. Johnson. Abigail P. Johnson is a Director, the ChairmanAvidity Capital Partners Fund (GP) LP, Avidity Capital Partners (GP) LLC, Avidity Master Fund LP, David Witzke and the Chief Executive Officer of FMR LLC. Members of the Johnson family, including Abigail P. Johnson, are the predominant owners, directly or through trusts, of Series B voting common shares of FMR LLC, representing 49% of the voting power of FMR LLC. The Johnson family group and all other Series B shareholders have entered into a shareholders’ voting agreement under which all Series B voting common shares will be voted in accordance with the majority vote of Series B voting common shares. Accordingly, through their ownership of voting common shares and the execution of the shareholders’ voting agreement, members of the Johnson family may be deemed, under the Investment Company Act of 1940, to form a controlling group with respect to FMR LLC. Neither FMR LLC nor Abigail P. Johnson has the sole power to vote or direct the voting of the shares owned directly by the various investment companies registered under the Investment Company Act (“Fidelity Funds”) advised by Fidelity Management & Research Company (“FMR Co”), a wholly owned subsidiary of FMR LLC, which power resides with the Fidelity Funds’ Boards of Trustees. FMR Co carries out the voting of the shares under written guidelines established by the Fidelity Funds’ Boards of Trustees. The address of FMR LLC is 245 Summer Street, Boston, Massachusetts 02210.
(5)

Based solely on a Schedule 13G filed with the SEC on February 14, 2019 by the following persons and entities with respect to shares of common stock beneficially owned as of December 31, 2018, consists of (i) 1,604,517 shares of common stock held by Frazier Healthcare VII, L.P. and (ii) 457,241 shares of common stock held by Frazier HealthcareVII-A, L.P. The general partner of Frazier Healthcare VII, L.P. and Frazier HealthcareVII-A, L.P. is FHM VII, L.P., a Delaware limited partnership. The general partner of FHM VII, L.P. is FHM VII, LLC, a Delaware limited liability company. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are members of FHM VII, LLC and may be deemed to share voting and investment power with respect to the shares held by FHM VII, LLC.Michael Gregory. The address of the above persons and entities is 601 Union,2828 N Harwood Street, Suite 3200, Seattle, Washington 98101.

1220, Dallas, Texas 75201.
(6)(3)

Based solely on information provided to Gritstone by The Nasdaq Stock Market LLC indicating beneficial ownership as of March 31, 2019. Trinitas Capital, Inc. is the general partner of Trinitas Capital G, L.P., and Cheng Zhou and Bing Han share management power of Trinitas Capital, Inc. and investment and voting power with respect to the shares held by Trinitas Capital G, L.P. The address of the above persons and entities is 401, 4/F Building 2, No. 39, Dongzhimenwai Street, Dongcheng District, Beijing, China.

(7)

Based solely on a Schedule 13G/A filed with the SEC on February 14, 2019 with respect to shares of common stock beneficially owned as of December 31, 2018, as updated by information provided to Gritstone by The Nasdaq Stock Market LLC as of March 31, 2019. Redmile Group, LLC’s beneficial ownership of our common stock is comprised of 2,514,136 shares of Common Stock owned by certain private investment vehicles and/or separately managed accounts managed by Redmile Group, LLC, which shares of Common Stock may be deemed beneficially owned by Redmile Group, LLC as investment manager of such private investment vehicles and/or separately managed accounts. The reported securities may also be deemed beneficially owned by Jeremy C. Green as the principal of Redmile Group, LLC. Redmile Group, LLC and Mr. Green each disclaim beneficial ownership of these shares, except to the extent of its or his pecuniary interest in such shares, if any. The address of the above person and entities is One Letterman Drive, Building D, SuiteD3-300, San Francisco, California 94129.

(8)

Consists of (i) 1,449,275 shares of common stock held directly by a family trust of which Dr. Allen isserves a trustee of which 1,388,889(ii) 14,321 shares will be vested as of 60 days after April 22, 2019 and 60,386 shares will continue to be subject to our repurchase right as of such date, and (ii) 34,921 shares that may be acquired pursuant to the exercise of stock options within 60 days of April 22, 2019.

(9)

Dr. Aphale terminated employment with Gritstone on March 12, 2019.

(10)

Consists of (i) 143,224 shares of common stock held by Dr. Yelensky, of which 131,291 shares will be vested as of 60 days after April 22, 2019Allen and 11,933 shares will continue to be subject to our repurchase right as of such date, and (ii) 44,735 shares that may be acquired pursuant to the exercise of stock options within 60 days of April 22, 2019.

(11)

Consists of 53,323 shares of common stock, 46,976 of which shares will be vested within 60 days of April 22, 2019, and 6,347 of which shares will continue to be subject to our repurchase right as of such date.

(12)

Consists of the shares described in footnote 3 above. Mr. Simon disclaims beneficial ownership of all such shares except to the extent of his pecuniary interests therein.

(13)

Consists of the shares described in footnote 2 above. Mr. Svennilson disclaims beneficial ownership of all such shares except to the extent of his pecuniary interests therein.

(14)

Consists of the shares described in footnote 1 above. Dr. Woiwode disclaims beneficial ownership of all such shares except to the extent of his pecuniary interests therein.

(15)

Consists of (i) 10,894,237 shares of common stock, of which 160,640 will continue to be subject to our repurchase right as of 60 days after April 22, 2019, and (ii) 327,512(iii) 531,858 shares of common stock that may be acquired pursuant to the exercise of stock options within 60 days of April 22, 2019.

March 31, 2022.
(4)
Consists of (i) 330,116 shares of common stock held by Dr. Jooss and (ii) 198,509 shares of common stock that may be acquired pursuant to the exercise of stock options within 60 days of March 31, 2022.
(5)
Consists of (i) 27,643 shares of common stock held by Mr. Jones and (ii) 237,469 shares of common stock that may be acquired pursuant to the exercise of stock options within 60 days of March 31, 2022.
(6)
Consists of (i) 53,323 shares of common stock held by Dr. Heyman and (ii) 21,070 shares of common stock that may be acquired pursuant to the exercise of stock options within 60 days of March 31, 2022.
(7)
Consists of 26,671 shares of common stock that may be acquired by Dr. Jones pursuant to the exercise of stock options within 60 days of March 31, 2022.
(8)
Consists of 36,016 shares of common stock that may be acquired by Mr. Krognes pursuant to the exercise of stock options within 60 days of March 31, 2022.
(9)
Consists of 4,222 shares of common stock that may be acquired by Ms. Fisher pursuant to the exercise of stock options within 60 days of March 31, 2022.
(10)
Consists of 11,611 shares of common stock that may be acquired by Dr. Agarwal pursuant to the exercise of stock options within 60 days of March 31, 2022.
(11)
Consists of 31,375 shares of common stock that may be acquired by Mr. Rizvi pursuant to the exercise of stock options within 60 days of March 31, 2022.
(12)
Consists of (i) 2,049,309 shares of common stock beneficially owned by our executive officers and directors and (ii) 1,262,903 shares of common stock that may be acquired pursuant to the exercise of stock options within 60 days of March 31, 2022 held by our executive officers and directors.
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SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

Section 16(a) of the Exchange Act requires the Company’s directors and executive officers, and persons who own more than 10% of a registered class of the Company’s equity securities, to file with the SEC initial reports of ownership and reports of changes in ownership of common stock and other equity securities of the Company. Officers, directors and greater than 10% stockholders are required by SEC regulations to furnish the Company with copies of all Section 16(a) forms they file.

To the Company’s knowledge, based solely on a review of the copies of such reports furnished to the Company and written representations that no other reports were required, the Company believes that all Section 16(a) filing requirements applicable to our officers, directors and greater than 10% beneficial owners were complied with during the year ended December 31, 2018.

2021, except that (i) several of our officers and directors were late in filing certain Forms 3 and 4, all of which were filed on November 19, 2021; and, (ii) one of our officers was late in filing certain Forms 4/A, all of which were filed of December 3, 2021.

ADDITIONAL INFORMATION

Householding of Proxy Materials

The SEC has adopted rules that permit companies and intermediaries (e.g., brokers) to satisfy the delivery requirements for proxy statements and annual reports with respect to two or more stockholders sharing the same address by delivering a single proxy statement addressed to those stockholders. This process, which is commonly referred to as “householding,” potentially means extra convenience for stockholders and cost savings for companies.

Brokers with account holders who are Gritstone stockholders may be “householding” our proxy materials. A single proxy statement may be delivered to multiple stockholders sharing an address unless contrary instructions have been received from 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 notify your broker or the Company that you no longer wish to participate in “householding.”

If, at any time, you no longer wish to participate in “householding” and would prefer to receive a separate proxy statement and annual report, you may (1) notify your broker or (2) direct your written request to: 58585959 Horton Street, Suite 210,300, Emeryville, CA 94608. Stockholders who currently receive multiple copies of this Proxy Statement at their address and would like to request “householding” of their communications should contact their broker. In addition, the Company will promptly deliver, upon written or oral request to the address or telephone number above, a separate copy of the Form10-K, Proxy Statement, Proxy Card or Notice of Internet Availability of Proxy Materials to a stockholder at a shared address to which a single copy of the documents was delivered.

Incorporation by Reference

Notwithstanding anything to the contrary set forth in any of our previous filings under the Securities Act of 1933, as amended, or the Securities Exchange Act, of 1934, as amended, which might incorporate future filings made by us under those statutes, the Audit Committee Report will not be incorporated by reference into any of those prior filings, nor will any such report be incorporated by reference into any future filings made by us under those statutes. In addition, information on our website, other than our proxy statement, notice and form of proxy, is not part of the proxy soliciting material and is not incorporated herein by reference.

Other Matters

As of the date of this Proxy Statement, the boardBoard of directorsDirectors does not intend to present any matters other than those described herein at the Annual Meeting and is unaware of any matters to be presented by other parties.

If other matters are properly brought before the Annual Meeting for action by the stockholders, proxies will be voted in accordance with the recommendation of the boardBoard of directorsDirectors or, in the absence of such a recommendation, in the discretion of the proxy holder.

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We have filed our Annual Report on Form10-K for the year ended December 31, 20182021 with the SEC. It is available free of charge at the SEC’s web site at www.sec.gov and our website at http://www.gritstoneoncology.com.www.gritstonebio.com. Upon written request by a Gritstone stockholder, we will mail without charge a copy of our Annual Report on Form10-K, including the financial statements and financial statement schedules, but excluding exhibits to the Annual Report on Form10-K. Exhibits to the Annual Report on Form10-K are available upon payment of a reasonable fee, which is limited to our expenses in furnishing the requested exhibit. All requests should be directed to the Corporate Secretary, 58585959 Horton Street, Suite 210,300, Emeryville, CA 94608.

​

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By Order of the Board of Directors

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​​
/s/ Andrew Allen

​​
Andrew Allen, M.D., Ph.D.

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President and Chief Executive Officer

April 26, 2019

28, 2022

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LOGO

VOTE BY INTERNET—www.proxyvote.com Use the Internet to transmit your voting instructions and for electronic delivery of information. Vote by 11:59 P.M. ET on June 18, 2019. Have your proxy card in hand when you access the web site and follow the instructions to obtain your records and to create an electronic voting instruction form. ELECTRONIC DELIVERYTABLE OF FUTURE PROXY MATERIALS GRITSTONE ONCOLOGY, INC. 5858 HORTON STREET, SUITE 210 If you would like to reduce the costs incurred by our company in mailing proxy materials, EMRYVILLE, CALIFORNIA 94608 you can consent to receiving all future proxy statements, proxy cards and annual reports electronically viae-mail or the Internet. To sign up for electronic delivery, please follow the instructions above to vote using the Internet and, when prompted, indicate that you agree to receive or access proxy materials electronically in future years. VOTE BYPHONE—1-800-690-6903 Use any touch-tone telephone to transmit your voting instructions. Vote by 11:59 P.M. ET on June 18, 2019. Have your proxy card in hand when you call and then follow the instructions. VOTE BY MAIL Mark, sign and date your proxy card and return it in the postage-paid envelope we have provided or return it to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717. TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS: KEEP THIS PORTION FOR YOUR RECORDS DETACH AND RETURN THIS PORTION ONLY THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED. For Withhold For All To withhold authority to vote for any All All Except individual nominee(s), mark “For All Except” and write the number(s) of the The Board of Directors recommends you vote FOR the following: nominee(s) on the line below.    0 0 0 1. Election of Directors    Nominees 01 Andrew Allen 02 Judith Li The Board of Directors recommends you vote FOR the following proposal: For Against Abstain 2    The ratification of the selection, by the audit committee of our board of directors, of Ernst & Young LLP, as    0 0 0    our independent registered public accounting firm for the year ending December 31, 2019. NOTE: Such other business as may properly come before the meeting or any adjournment thereof. For address change/comments, mark here.                0 18 . (see reverse for instructions) . 1 . 0    R1 1 _ Please sign exactly as your name(s) appear(s) hereon. When signing as attorney, executor, administrator, or other fiduciary, please give full title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or 0000422504 partnership name, by authorized officer. Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date    CONTENTS


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LOGO

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting: The Annual Report, Notice & Proxy Statement is/ are available at www.proxyvote.com GRITSTONE ONCOLOGY, INC. Annual Meeting of Stockholders June 19, 2019 9:00 AM PDT This proxy is solicited by the Board of Directors The stockholders hereby appoint Andrew Allen and Jean-Marc Bellemin, or either of them, as proxies, each with the power to appoint his substitute, and hereby authorize them to represent and to vote, as designated on the reverse side of this ballot, all of the shares of common stock of GRITSTONE ONCOLOGY, INC. that the stockholders are entitled to vote at the Annual Meeting of stockholders to be held at 09:00 AM, PDT on June 19, 2019, at www.virtualshareholdermeeting.com/GRTS2019, and any adjournment or postponement thereof. This proxy, when properly executed, will be voted in the manner directed herein. If no such direction is made, this proxy will be voted in accordance with the Board of Directors’ recommendations. Address change/comments: . 18 . 1 . 0    R1 _ 2 0000422504 (If you noted any Address Changes and/or Comments above, please mark corresponding box on the reverse side.) Continued and to be signed on reverse side