UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934 (Amendment No.    )

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

Check the appropriate box:

EXELIXIS, INC.

(Exact 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):

DEAR FELLOW STOCKHOLDERS,

While we could never have envisioned the magnitude and impact of the COVID-19 pandemic, Exelixis responded well to the challenges presented and never lost focus of its critical mission to help cancer patients recover stronger and live longer. We, writeand the rest of the Board, are incredibly proud of the entire Exelixis team’s ability throughout 2020 to advance the company’s business, while always putting the highest priority on protecting one another’s health and safety and ensuring an uninterrupted supply of Exelixis medicines for the patients that depend upon them. Exelixis’ actions reflect its core values to Be Exceptional, Excel for Patients and Exceed Together.

The success and growth Exelixis achieved in 2020 would be noteworthy in any year, but is even more striking in the context of the pandemic. In particular, we:

Our achievements during the year were supported by a strong foundation of sound governance practices, including the continued evolution of our governance profile to reflect the scale and opportunity of our business. Launched shortly before the onset of the pandemic, the newly established Risk Committee of the Board served as an additional avenue through which management was able to communicate to the Board on the impact of and responses to the COVID-19 pandemic. In addition, the existing Research & Development and Compensation Committees provided important oversight and support for the drug discovery and development activities integral to our progress, and also worked with management to support the company’s efforts to recruit, retain, and cultivate the unified workforce that accomplished so much during the year.

Critical to our success in 2020 was the dedication of our employees and our collective ability to maintain the Exelixis culture of resilience, despite a primarily remote work environment. As a socially responsible company conscious of the expanding racial injustice movement, it was also critical for us to focus on our human capital management strategy and equity, diversity and inclusion initiatives. While there is always work to do, we are proud of our progress and are committed to fostering a culture where every employee feels a sense of belonging to the Exelixis team and our mission.

Exelixis’ accomplishments last year not only create the potential for additional eligible cancer patient communities to benefit from CABOMETYX and the investigational products in our growing pipeline, but we believe they also position us very well to deliver long-term revenue and earnings growth and continue to create value for our stockholders. We remain committed to delivering results for all of our stakeholders, and we thank you for your continued interest in Exelixis, and your confidence in the company’s ability to execute on its mission to accelerate the discovery, development and commercialization of new medicines forsupport.

difficult-to-treat cancers. As we navigate theCOVID-19 pandemic, now more than ever we recognize the critical importance of this company – and more broadly the importance of a strong and innovative biotech industry – in confronting the most serious medical challenges, such as cancer, and developing innovative medicines that can give patients and their familiesWe hope you will join us for the future.

As detailed in the accompanying letter from Michael Morrissey and in our Annual Report, Exelixis’ 25^th year was one of strong performance, financially, operationally and strategically. The company produced record annual net product revenues, dramatically increased its understanding of the broad therapeutic potential of cabozantinib, and gained strong momentum pursuing the expansion of its product pipeline through internal discovery andin-licensing activities. These achievements strengthened our foundation, giving us reason to be optimistic as we strive to continue Exelixis’ growth and create value for all of its stakeholders.

During the last year, we also announced the launch of a variety of environmental, social and governance (ESG) initiatives that reflect our ESG values. We appreciate the ongoing dialogue with our stakeholders as we have elicited input from numerous groups regarding the ESG issues that are most material to the company’s current and future activities. We are pleased to highlight that in 2019, the Exelixis Board continued to optimize our corporate governance profile, most notably by amending our Bylaws to provide stockholders with the right to call a special meeting. The Board approved this change following extensive engagement with our stockholders, during which special meetings were identified as critical to the ability of stockholders to act on matters that may arise between annual meetings. We believe this change demonstrates the Board’s dedication to being responsive to stockholder input concerning governance and we remain committed to the ongoing evaluation of our governance profile as Exelixis and its business evolve.

Next up is the Exelixis 20202021 Annual Meeting of Stockholders, which will be held in a virtual format on May 20, 2020,26, 2021, beginning at 10:9:00 a.m. Pacific Time. We have moved to a virtual format dueDue to the emergingongoing public health impact of theCOVID-19 pandemic and to support the health and well-being of our stockholders and employees.employees, we determined it would be appropriate to maintain the virtual format we used for last year’s meeting. You will be able to view the meeting, submit questions and vote online atwww.virtualshareholdermeeting.com/EXEL2020EXEL2021. The following notice of our Annual Meeting contains details of the business to be conducted at the Annual Meeting, as well as information regarding how and when to vote.

We appreciate your attention and hope for the best for you and your families during this challenging period.

Very truly yours,

Stelios Papadopoulos, PhD Chair of the Board		Charles Cohen, PhD     Chair of the Compensation Committee

1851 Harbor Bay Parkway

Alameda, CA 94502

NOTICEOF ANNUAL MEETING

OF STOCKHOLDERS

To Be Held on May 20, 2020TO BE HELDON MAY 26, 2021

To the Stockholders of Exelixis, Inc.:

NOTICE IS HEREBY GIVEN that the 20202021 Annual Meeting of Stockholders (Annual Meeting) of Exelixis, Inc., a Delaware corporation (Exelixis), will be held on Wednesday, May 20, 2020,26, 2021, at 10:9:00 a.m., Pacific Time. The Annual Meeting will be a completely virtual meeting of stockholders, which will be conducted via live webcast. You will be able to attend the virtual Annual Meeting, andview our list of stockholders as of the record date, submit your questions and vote your shares online during the meeting by visitingwww.virtualshareholdermeeting.com/EXEL2020EXEL2021 and using your16-digit control number to enter the Annual Meeting. In addition, you may submit your questions and vote your shares online in advance of the meetingAnnual Meeting by visitingwww.proxyvote.com and using your16-digit control number. The Annual Meeting will be held for the following purposes:

These items of business are more fully described in the Proxy Statement accompanying this Notice of Annual Meeting.

You will only be able to attend the virtual Annual Meeting by using your16-digit control number provided on your Notice of Internet Availability of Proxy Materials (Notice of Availability), your proxy cardorcardor your voting instruction form in order to gain access to the virtual Annual Meeting. Therefore, it is important to retain your Notice of Internet Availability of Proxy Materials or a copy of your proxy card or voting instruction form to enable you to gain access to the virtual Annual Meeting. If you are a beneficial owner of shares held in “street name” who did not receive a 16-digit control number via email or on your Notice of Availabilty or voting instruction form, and you wish to attend the Annual Meeting, please follow the specific instructions from your broker, bank or other stockholder of record, including any requirement to obtan a valid legal proxy.

We are mailing to most of our stockholders a Notice of Internet Availability of Proxy Materials (Notice of Availability) instead of a paper copy of thisour Proxy Statement and our Annual Report for the fiscal year ended January 3, 20201, 2021 (Annual Report). The Notice of Availability contains instructions on how to access those documents over the Internet. The Notice of Availability also contains instructions on how to request a paper copy of our proxy materials, including this Proxy Statement, our Annual Report and a form of proxy card or voting instruction form. All stockholders who do not receive a Notice of Availability will receive a paper copy of the proxy materials by mail. We believe that this process will allow us to provide our stockholders with the information they need in a more timely manner, while reducing the environmental impact and lowering the costs of printing and distributing our proxy materials.

The record date for the Annual Meeting is March 23, 2020.29, 2021. Only stockholders of record at the close of business on that date may vote at the meeting or any postponement or adjournment thereof.

By Order of the Board of Directors

JEFFREY J. HESSEKIEL

Executive Vice President and General Counsel

Alameda, California

April 9, 202015, 2021

YOUR VOTE IS IMPORTANT

WHETHER OR NOT YOU PLAN TO ATTEND THE VIRTUAL ANNUAL MEETING, TO ENSURE THAT YOU ARE REPRESENTED AT THE MEETING AND TO ENSURE THAT A QUORUM IS PRESENT, WE URGE YOU TO VOTE YOUR PROXY ONLINE, BY TELEPHONE OR BY RETURNING A PROXY CARD BY MAIL AS INSTRUCTED IN THE NOTICE OF AVAILABILITY OF PROXY MATERIALS. EVEN IF YOU HAVE VOTED BY PROXY, YOU MAY STILL VOTE IF YOU ATTEND THE VIRTUAL ANNUAL MEETING. PLEASE NOTE, HOWEVER, THAT IF YOU HOLD YOUR SHARES THROUGH A BROKER, BANK OR OTHER NOMINEE, THEN THAT ENTITY IS THE STOCKHOLDER OF RECORD, AND YOU WILL NEED TO FOLLOW THE INSTRUCTIONS ON THE VOTING INSTRUCTION FORM THEY SEND TO YOU, AND THEY WILL VOTE YOUR SHARES AS YOU DIRECT, DIRECT.

1851 Harbor Bay Parkway

Alameda, CA 94502

PROXY STATEMENT

FOR YOU MUST OBTAINTHE 2021 A PROXY ISSUED IN YOUR NAME FROM THAT ENTITY TO VOTE YOUR SHARES.NNUAL MEETINGOF STOCKHOLDERS

May 26, 2021

Proposals to be voted on at the 2021 Annual Meeting of Stockholders

Table of Contents

TABLE OF CONTENTS

2020 Proxy Statement    i

Proxy Statement | Questions and Answers about these Proxy Materials and Voting

1851 Harbor Bay Parkway

Alameda, CA 94502

PROXY STATEMENT

FORTHE 2020 ANNUAL MEETINGOF STOCKHOLDERS

MAY 20, 2020

QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING

Why am I receiving these materials?

We have made these materials available to you on the Internet or, upon your request, have delivered printed versions of these materials to you by mail because the Board of Directors (the Board), of Exelixis, Inc. (sometimes referred to as “we,” “us,” the “company” or “Exelixis”) is soliciting your proxy to vote at the 20202021 Annual Meeting of Stockholders (Annual Meeting), including at any adjournments or postponements of the meeting. The virtual Annual Meeting will be held on Wednesday, May 20, 2020,26, 2021, at 10:9:00 a.m., Pacific Time, via live webcast atwww.virtualshareholdermeeting.com/EXEL2020EXEL2021. We invite you to attend the virtual Annual Meeting to vote on the proposals described in this Proxy Statement, and you will need your16-digit control number provided on your Notice of Internet Availability of Proxy Materials (described below), your proxy card or your voting instruction form in order to gain access to the virtual Annual Meeting. Therefore, it is important to retain your Notice of Internet Availability of Proxy Materials or a copy of your proxy card or voting instruction form to enable you to gain access to the virtual Annual Meeting. However, you do not need to attend the virtual Annual Meeting to vote your shares. Instead, you may simply complete, sign and return a proxy card, or follow the instructions below or in the Notice of Internet Availability of Proxy Materials to submitvote your proxyshares over the telephone or on the Internet.

We intend to send or make available these materials to stockholders on April 9, 2020.15, 2021.

Why is the Annual Meeting being held as a virtual Annual Meeting?

Due to concerns regarding theCOVID-19 pandemic and to assist in protecting the health and well-being of our stockholders and employees, the Annual Meeting will be held virtually via live webcast on the Internet. WeAfter utilizing a virtual format for our 2020 Annual Meeting of Stockholders, we have designed thea similar virtual format offor the Annual Meeting to ensure that our stockholders who attend virtually will be afforded the same rights and opportunities to participate as they would at anin-person meeting. Accordingly, as stockholders from any location at the world and at no cost, you will be able to listen, submit your questions and vote your shares online regardless of location atwww.virtualshareholdermeeting.com/EXEL2020EXEL2021 by using your16-digit control number provided on your Notice of Internet Availability of Proxy Materials, your proxy card or your voting instruction form that accompanied your proxy materials. In addition, you may submit your questions and vote your shares online in advance of the meeting by visitingwww.proxyvote.com and using your16-digit control number.

The live webcast will begin promptly at 10:9:00 a.m., Pacific Time. We encourage you to access the meeting prior to the start time, as you should allow ample time for thecheck-in procedures.

What is included in these proxy materials?

These proxy materials include:

If you requested printed versions by mail, these proxy materials also include the proxy card or voting instruction form for the virtual Annual Meeting.

2020 Proxy Statement    1

In addition, a stockholder may ask to receive proxy materials in printed form by mail or electronically by email on an ongoing basis. We encourage stockholders to take advantage of the option to receive proxy materials electronically by email to help reduce the environmental impact of our annual meeting and to reduce costs associated with the physical printing and mailing of materials. If you choose to receive future proxy materials by email, you will receive an email message next year with instructions containing a link to those materials and a link to the proxy voting website. Your election to receive proxy materials by email will remain in effect until you terminate it.

How can I access the list of stockholders of record?

The list of stockholders of record entitled to vote at the virtual Annual Meeting will be available for 10 days prior to the Annual Meeting for any purpose germane to the Annual Meeting, between the hours of 9:00 a.m. and 5:00 p.m., Pacific Time, at our principal executive offices located at 1851 Harbor Bay Parkway, Alameda, California 94502 by contacting our Corporate Secretary. Due to the COVID-19 pandemic, registered stockholders must make an appointment and must comply with our COVID-19 protocols.

The list of stockholders of record will also be available at and through the conclusion of the Annual Meeting via the virtual meeting website at www.virtualshareholdermeeting.com/EXEL2021.

Who may vote at the Annual Meeting?

Only stockholders of record at the close of business on March 23, 202029, 2021 (the Record Date) will be entitled to vote at the virtual Annual Meeting. On the Record Date, there were 305,733,496313,097,850 shares of common stock outstanding and entitled to vote.

Stockholder of Record: Shares Registered in Your Name

If on March 23, 2020,29, 2021, your shares were registered directly in your name with our transfer agent, Computershare Trust Company, N.A., then you are a stockholder of record. As a stockholder of record, you may vote at the virtual Annual Meeting or vote by proxy. Whether or not you plan to attend the virtual Annual Meeting, we urge you to vote by proxy over the telephone or on the Internet as instructed below, or complete and mail the proxy card if you received printed materials.

Beneficial Owner: Shares Registered in the Name of a Broker, Bank or Other Stockholder of Record (i.e., “Street Name”)

If on March 23, 2020,29, 2021, 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 shares is considered to be the stockholder of record for purposes of voting at the virtual Annual Meeting. As a beneficial owner, you have the right to direct your broker, bank or other stockholder of record regarding how to vote the shares in your account, and we invite you to attend the virtual Annual Meeting. Many stockholders of record will provide you with a 16-digit control number via email or in your Notice of Availability or voting instruction form in order to attend and vote your shares at the virtual Annual Meeting. If you did not receive a 16-digit control number via email or on your Notice of Availabilty or voting instruction form, you will receivebe provided with other instructions from your broker, bank or other stockholder of record that must be followed, including any requirement to obtan a valid legal proxy, in order for your broker, bank or other stockholder of record to vote your shares per your instructions. You are also invitedinstructions or to attend the virtual Annual Meeting. However, since you are not the stockholder of record, you may notand vote your shares at the virtual Annual Meeting unless you request andMeeting. Many brokers, banks or other stockholders of record allow a stockholder to obtain a valid legal proxy fromeither online or by mail, and we recommend that you contact your broker, bank or other stockholder of record giving you the right to vote such shares at the virtual Annual Meeting.do so.

What am I voting on?

There are fourthree matters scheduled for a vote at the virtual Annual Meeting. They are as follows:

2    Exelixis, Inc.

Proxy Statement | Questions and Answers about these Proxy Materials and Voting

How do I vote?

Whether or not you plan to attend the virtual Annual Meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the virtual Annual Meeting and vote even if you have already voted by proxy.

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you have four ways to vote.

At Virtual Meeting		››		To vote at the virtual Annual Meeting, follow the instructions at www.virtualshareholdermeeting.com/EXEL2020EXEL2021. You will need your16-digit control number provided on your Notice of Internet Availability, of Proxy Materials, your proxy card or your voting instruction form in order to gain access to the virtual Annual Meeting.
Via Internet		››		To vote on the Internet, go towww.proxyvote.com and follow the instructions provided in the Notice of Availability. You will need your16-digit control number provided on your Notice of Internet Availability, of Proxy Materials, your proxy card or your voting instruction form in order to vote your shares in advance of the meeting. Your vote must be received by 11:59 p.m., Eastern Time, on May 19, 2020,25, 2021, to be counted.
By Telephone		››		To vote by telephone, request a paper or email copy offollow the proxy materials by following the instructions provided in the Notice of Availability and call the number provided within the proxy materials to transmit your voting instructions. Your vote must be received by 11:59 p.m. Eastern Time, on May 19, 2020,25, 2021, to be counted.
By Mail		››		To vote by mail, follow the instructions provided in the proxy materials, request a paper copy of the proxy materials by following the instructions provided in the Notice of Availability and then complete, sign and date the proxy card enclosed with the paper copy of the proxy materials and return it promptly in the envelope that will be provided. If you return your signed proxy card to us before the Annual Meeting, we will vote your shares as you direct.

Beneficial Owner: Shares Registered in the Name of Broker, Bank or Other Stockholder of Record (i.e.,“Street Name”)

If you are a beneficial owner of shares registered in the name of your broker, bank, or other stockholder of record, you should have received the Notice of Availability containing voting instructions from that organization rather than from us. You must follow these instructions for your bank, broker or other stockholder of record to vote your shares per your instructions. Alternatively, many brokers and banks provide the means to grant proxies or otherwise instruct them to vote your shares by telephone and via the Internet.Internet, including by providing you with a 16-digit control number via email or on your Notice of Availability or your voting instruction form. If your shares are held in an account with a broker, bank or other stockholder of record providing such a service, you may grant a proxyinstruct them to vote thoseyour shares by telephone (by calling the number provided in the proxy materials) or over the Internet as instructed by your broker, bank or other stockholder of record. ToIf you did not receive a 16-digit control number via email or on your Notice of Availability or voting instruction form, and you wish to vote prior to or at the virtual Annual Meeting, you must obtain a valid legal proxy from your broker, bank or other stockholder of record. Followfollow the instructions from your broker, bank or other stockholder of record, included with theseincluding any requirement to obtain a valid legal proxy.. Many brokers, banks and other stockholders of record allow a beneficial owner to obtain a valid legal proxy materials,either online or by mail, and we recommend that you contact your broker, bank or other stockholder of record to request a legal proxy.do so.

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, March 23, 2020.29, 2021.

How are proxies voted?

All shares represented by valid proxies received prior to the taking of the vote at the Annual Meeting will be voted and, where a stockholder specifies by means of a proxy a choice with respect to any matter to be acted upon, the shares will be voted in accordance with the stockholder’s instructions.

2020 Proxy Statement    3

If I am a stockholder of record, what happens if I return a proxy card but do not make specific choices?

If you are a stockholder of record and you return a signed and dated proxy card without marking any voting selections, your shares will be voted on the proposals as follows:

If any other matter is properly presented at the Annual Meeting, your proxyholder (one of the individuals named on your proxy card), if permitted, will vote your shares using his best judgment.

If I am a beneficial owner of shares held in street name and I do not provide my broker or bank with voting instructions, what happens?

If you are a beneficial owner of shares registered in the name of your broker, bank or other stockholder of record and you do not provide the broker, bank or other stockholder of record holding your shares with voting instructions, your broker, bank or other stockholder of record will determine if it has the discretionary authority to vote on the particular matter. If you are a beneficial owner whose shares are held of record by a broker and you do not provide voting instructions, your shares will not be voted on any proposal on which the broker does not have discretionary authority to vote. This is called a “brokernon-vote.” In these cases, the broker can register your shares as being present at the Annual Meeting for purposes of determining the presence of a quorum, but will not be able to vote on those matters for which specific authorization is required under the rules of the New York Stock Exchange.

If you are a beneficial owner whose shares are held of record by a broker, your broker has discretionary voting authority under the rules of the New York Stock Exchange to vote your shares on Proposal No. 2 (the ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending January 1,December 31, 2021), even if your broker does not receive voting instructions from you. However, your broker does not have discretionary authority to vote on Proposal No. 1 Proposal No. 3 or Proposal No. 43 without voting instructions from you, in which case a brokernon-vote will occur, and your shares will not be voted on Proposal No. 1 Proposal No. 3 or Proposal No. 4.3.

Who is paying for this proxy solicitation?

We are soliciting proxies and will bear the entire cost of soliciting proxies, including the preparation, printing and mailing of the Notice of Availability, the Notice of Annual Meeting, the Proxy Statement, the proxy card and any additional information furnished to stockholders. We have engaged Morrow Sodali LLC, located at 470 West Ave, Stamford, Connecticut 06902, to assist in the solicitation of proxies from shareholders for a fee of $13,000 plus reimbursement of customaryout-of-pocket expenses. Copies of solicitation materials will be furnished to banks, brokerage houses, fiduciaries and custodians holding in their names shares of our common stock beneficially owned by others to forward to such beneficial owners. We may reimburse persons representing beneficial owners of our common stock for their costs of forwarding solicitation materials to such beneficial owners. Original solicitation of proxies by mail may be supplemented by telephone, telegram or personal solicitation by our directors, officers or other regular employees. No additional compensation will be paid to directors, officers or other regular employees for such services.

What does it mean if I receive more than one Notice of Availability or proxy card?

If you receive more than one Notice of Availability or proxy card, your shares are registered in more than one name or are registered in different accounts. Please follow the instructions on each Notice of Availability or proxy card to ensure that all of your shares are voted.

4    Exelixis, Inc.

Proxy Statement | Questions and Answers about these Proxy Materials and Voting

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. You may revoke your proxy in the following ways:

Stockholder of Record: Shares Registered in Your Name

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

What is the quorum requirement for the Annual Meeting?

A majority of the outstanding shares entitled to vote at the virtual Annual Meeting must be present or represented by proxy at the Annual Meeting to hold a valid meeting. This is called a “quorum.” As this is a virtual Annual Meeting, holders of record attending via the live webcast will be deemed to be present at the virtual Annual Meeting.

If you are a stockholder of record, your shares will be counted towards the quorum only if you vote at the virtual Annual Meeting or have properly voted by proxy on the Internet, by telephone or by submitting a proxy card by mail. You may vote “For,” “Against” or “Abstain” with respect to Proposal Nos. 1, 2 3 and 4.3. Abstentions will be counted towards the number of shares considered to be present at the meeting for purposes of determining whether a quorum is present.

If you are a beneficial owner holding your shares in “street name” then only the broker, bank or other stockholder of record can vote your shares unless you obtain a valid legal proxy from the broker, bank or other stockholder of record.record, or are otherwise provided with a separate means to vote your shares (such as a 16-digit control number provided via email or on your Notice of Availability or voting instruction form). See “If I am a beneficial owner of shares held in street name and I do not provide my broker or bank with voting instructions, what happens?” above. Shares represented by “brokernon-votes” will be counted in determining whether there is a quorum present.

Votes will be counted by the inspector of election appointed for the Annual Meeting. If there is no quorum, either the chairperson of the Annual Meeting or the holders of a majority of shares present or represented by proxy at the Annual Meeting may adjourn the Annual Meeting to another date.

How many votes are needed to approve each proposal, how are votes counted, and how are abstentions and brokernon-votes treated?

2020 Proxy Statement    5

Do I have dissenters’ rights?

No. We are organized as a corporation under Delaware law. Under the Delaware General Corporation Law, our stockholders are not entitled to dissenters’ rights with respect to any of the proposals set forth in this Proxy Statement and we will not independently provide the stockholders with any such rights.

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

We expect to announce preliminary voting results at the Annual Meeting. In addition, final voting results will be published in a current report on Form8-K that we expect to file within four business days after the Annual Meeting. If final voting results are not available to us in time to file a Form8-K within four business days after the Annual Meeting, we intend to file aForm 8-K to publish preliminary results and, within four business days after the final results are known to us, file an additional Form8-K to publish the final results.

Will other matters be voted on at the Annual Meeting?

We are not aware of any matters to be presented at the Annual Meeting other than those described in this Proxy Statement. If any other matters not described in the Proxy Statement are properly presented at the meeting, proxies will be voted in accordance with the best judgment of the proxyholders.

What proxy materials are available on the Internet?

This Proxy Statement and our Annual Report are available atwww.exel-annualstockholdermeeting.com.

What is the deadline for submitting stockholder proposals for the 20212022 Annual Meeting?

To be considered for inclusion in the 20212022 proxy materials, your proposal must be submitted in writing by December 11, 2020,[16], 2021, to Exelixis’ Secretary at Exelixis, Inc., 1851 Harbor Bay Parkway, Alameda, California 94502, and you must comply with all applicable requirements of Rule14a-8 promulgated under the Securities Exchange Act of 1934, as amended (Exchange Act). However, if our 20212022 Annual Meeting of Stockholders is held before April 20, 2021,26, 2022, or after June 19, 2021,25, 2022, then the deadline will be a reasonable time prior to the time that we make our proxy materials available to our stockholders, either online or in printed form.

If you wish to submit a proposal or nominate a director at the 20212022 Annual Meeting of Stockholders, but you are not requesting that your proposal or nomination be included in next year’s proxy materials, you must submit your proposal in writing, in the manner set forth in our Bylaws, to Exelixis’ Secretary at Exelixis, Inc., 1851 Harbor Bay Parkway, Alameda, California 94502, to be received no earlier than the close of business on February 19, 2021,25, 2022, and no later than the close of business on March 21, 2021.27, 2022. However, if our 20212022 Annual Meeting of Stockholders is held before April 20, 2021,26, 2022, or after June 19, 2021,25, 2022, then you must notify Exelixis’ Secretary, in writing, not earlier than the close of business on the 90th day prior to the date of the 20212022 Annual Meeting of Stockholders and not later than the close of business on the later of (i) the 60th day prior to the date of the 20212022 Annual Meeting of Stockholders or (ii) if we publicly announce the date of the 20212022 Annual Meeting of Stockholders fewer than 70 days prior to the date of the 20212022 Annual Meeting of Stockholders, the 10th day following the day that we first make such public announcement of the date of the 20212022 Annual Meeting of Stockholders. We also advise you to review our Bylaws, which contain additional requirements about advance notice of stockholder proposals and director nominations. The chairperson of the 20212022 Annual Meeting of Stockholders may determine, if the facts warrant, that a matter has not been properly brought before the meeting and, therefore, may not be considered at the meeting. In

6    Exelixis, Inc.

Proxy Statement | Questions and Answers about these Proxy Materials and Voting

How may I obtain a printed copy of the Proxy Materials?

Instructions on how to obtain a printed copy of the proxy materials are set forth in the Notice of Availability.

Forward-Looking Statements

This Proxy Statement contains forward-looking statements, including, without limitation, statements related to: Exelixis’ expectations that its employees and partners will commit to the highest standards of ethical behavior and maintain values and principles that reflect both global awareness and sustainability; Exelixis’ dedication of financial resources to offer patients high-quality cancer treatments and commitment to providing patients with access to Exelixis medicines; Exelixis’ strategies for quality monitoring and compliance in developing its products; Exelixis’ potential to attain future environmental stability; Exelixis’ ongoing efforts towards the achievement of key priorities and anticipated milestones for 20202021 and 2021, including generatingtop-line data frombeyond; Exelixis’ expectation that the combination of CABOMETYX and OPDIVO will be a key clinical trials, completing enrollmentdriver of ongoing studies, initiating new pivotal trials,revenue growth; Exelixis’ plans to file with the FDA for accelerated approval of the combination of cabozantinib and progressingatezolizumab in an mCRPC indication, if warranted by the data; the potential for Exelixis to add clinical-stage assets to itsmid-stage and early product pipeline; the anticipated organizational growth of Exelixis; Exelixis’ market strategiesstrategic planning for potential future commercial indications for cabozantinib, the further development of XL092 and other potential business development assets; Exelixis’ plans to initiate variouspre-clinical studies in the first half of 2020; and other statements that are not historical fact. Any statements that refer to expectations, projections or other characterizations of future events or circumstances are forward-looking statements and are based upon Exelixis’ current plans, assumptions, beliefs, expectations, estimates and projections. Forward-looking statements involve risks and uncertainties. Actual results and the timing of events could differ materially from those anticipated in the forward-looking statements as a result of these risks and uncertainties, which include, without limitation: the continuing COVID-19 global pandemic and its impact on our research and development operations, including our ability to initiate new clinical trials andExelixis’ clinical trial, sites, enroll clinical trial patients, conduct trials per protocol,drug discovery and conduct drug research and discovery operations and relatedcommercial activities; the degree of market acceptance of CABOMETYX and other Exelixis products in the indications for which they are approved and in the territories where they are approved, and Exelixis and its partners’ abilitiesability to obtain or maintain coverage and reimbursement for these products; the effectiveness of CABOMETYX and other Exelixis products in comparison to competing products; the level of costs associated with Exelixis’ commercialization, research and development, in-licensing or acquisition of product candidates, and other activities; Exelixis’ ability to maintain and scale adequate sales, marketing, market access and product distribution capabilities for its products or to enter into and maintain agreements with third parties to do so; the availability of data at the referenced times; the potential failure of cabozantinib and other Exelixis product candidates, both alone and in combination with other therapies, to demonstrate safety and/or efficacy in clinical testing; uncertainties inherent in the drug discovery and product development process; Exelixis’ dependence on its relationships with its collaboration partners, including their pursuit of regulatory approvals for partnered compounds in new indications, their adherence to their obligations under relevant collaboration agreements and the level of their investment in the resources necessary to complete clinical trials or successfully commercialize partnered compounds in the territories where they are approved; complexities and the unpredictability of regulatory review and approval processes in the USU.S. and elsewhere, including the risk that regulatory authorities may not approve Exelixis’ products as treatments for the indications in which approval has been sought, if at all;elsewhere; Exelixis’ continuing compliance with applicable legal and regulatory requirements; unexpected concerns that may arise as a result of the occurrence of adverse safety events or additional data analyses of clinical trials evaluating cabozantinib and other Exelixis products; Exelixis’ dependence on third-party vendors for the development, manufacture and supply of its products;products and product candidates; Exelixis’ ability to protect its intellectual property rights; market competition, including the potential for competitors to obtain approval for generic versions of Exelixis’ marketed products; changes in economic and business conditions; and other factors discussed under the caption “Risk Factors” in Exelixis’ Annual Report onForm 10-K filed withsubmitted to the SEC on February 25, 2020,10, 2021, and in Exelixis’ future filings with the SEC. All forward-looking statements in this Proxy Statement are based on information available to Exelixis as of the date of this Proxy Statement, and Exelixis undertakes no obligation to update or revise any forward-looking statements contained herein, except as required by law.

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PROPOSAL 1

ELECTIONOF DIRECTORS

Prior to the 2019 Annual Meeting of Stockholders, ourOur Certificate of Incorporation and Bylaws provided that the Board was divided into three classes, with each class having a three-year term. At the 2019 Annual Meeting of Stockholders, our stockholders approved an amendment to our Certificate of Incorporation to declassify the Board to provide for the annual election of each director bydirector. There are currently eleven directors on the Annual Meeting. Accordingly, beginning with the Annual Meeting, each director is to be considered for election by our stockholders for a term expiring at the next annual meeting of stockholders; theBoard, and all eleven director nominees listed belowdirectors have been nominated and are standing forre-election this year:

Proposal 1 | Election of Directors

Board Independence, Diversity and Skills

The Board regularly evaluates the skills and experiences that it believes are desirable to be represented on the Board and best align with our strategic vision and business and operations. Below are certain qualifications, skills and experiences of our current directors that contribute the Board’s effectiveness as a whole.

In addition, set forth below is biographical information for each nominee for election to our Board at the Annual Meeting. Incorporated within each biography is a description of the specific qualifications, skills and experiences of each nominee that led our Board to conclude that the individual should serve as a director as of the date of this Proxy Statement.

2020 Proxy Statement    9

Director Nominees

10    Exelixis, Inc.

Proposal 1 | Director Nominees

2020 Proxy Statement    11

12    Exelixis, Inc.

Proposal 1 | Director Nominees

2020 Proxy Statement    13

14    Exelixis, Inc.

Proposal 1 | Director Nominees

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Corporate Governance

Please note that information found on, or accessible through, our website is not a part of, and is not incorporated into, this Proxy Statement.

Corporate Governance Guidelines

We have adopted written Corporate Governance Guidelines, which may be viewed atwww.exelixis.com under the caption “Investors & Media—Corporate Governance—Corporate Governance Documents.” This document covers, among other topics, director independence, board composition, structure and functioning, director selection criteria, committees of the board, board and board committee evaluations, overboarding guidelines and our majority voting policy. Our Board regularly reviews, and modifies from time to time, our Corporate Governance Guidelines, Board committee charters and Board practices.

Corporate Code of Conduct

We have adopted a Corporate Code of Conduct, which functions as our Code of Ethics under the SEC rules and applies to all directors, officers and employees, including the principal executive officer and principal financial/accounting officer. The Corporate Code of Conduct is posted on our website atwww.exelixis.com under the caption “Investors & Media—Corporate Governance—Corporate Governance Documents.” We intend to satisfy the disclosure requirement under Item 5.05 ofForm 8-K regarding an amendment to, or waiver from, a provision of this Corporate Code of Conduct by posting such information on our website, at the address and location specified above and, to the extent required by the listing standards of the Nasdaq Stock Market, by filing a Current Report on Form8-K with the SEC, disclosing such information.

Our Corporate Code of Conduct reflects our corporate values and describes how our officers, directors, employees and contractors are expected to conduct themselves when representing Exelixis. It also underscores our commitment to strive to comply with laws that regulate our business activities as a biotechnology company. Our employees receive regular training on our Corporate Code of Conduct, which includes consequences of taking actions that would constitute a violation of our Corporate Code of Conduct.

Included in our Corporate Code of Conduct are procedures for employees to report potential violations to our Ethics Committee, which is chaired by our Chief Executive Officer and includes other members of our senior management team. To ensure our employees feel comfortable raising good faith questions or concerns with respect to our Corporate Code of Conduct or our other policies, these reports can be made confidentially (or anonymously) via our Ethics Hotline, and we maintain a strict policy against any retaliation or discrimination towards an employee who makes such a report. The Board, through the Audit Committee, regularly receives reports of disclosures made through the Ethics Hotline, as well as any concerns raised to the Ethics Committee or otherwise submitted through our internal compliance reporting system. The Audit Committee will beis responsible for the oversight of such matters, or as appropriate, will assign such oversight to another committee of the Board.

Director Independence

We have adopted standards for director independence pursuant to Nasdaq listing standards, which require that a majority of the members of a listed company’s board of directors qualify as “independent,” as affirmatively determined by the board of directors. An “independent director” means a person other than an officer or employee of Exelixis or one of our subsidiaries, or another individual having a relationship that, in the opinion of the Board, would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. Consistent with these considerations, after review of all relevant transactions or relationships between each director, or any of his or her family members, and Exelixis, its senior management or its independent registered public accounting firm, the Board has affirmatively determined that Drs. Cohen, Freire, Garber, Marchesi, Papadopoulos, Poste Scangos and Willsey, Messrs. Wyszomierski and Feldbaum and Ms. Smith, who are eleventen of the twelveeleven members of the Board, represent a majority of the Board and are independent under applicable SEC rules and the Nasdaq listing standards. Dr. Morrissey, our President and Chief Executive Officer, is not independent by virtue of his employment with Exelixis. In addition, the Board has also determined that: (i) all directors who serve on the Audit, Compensation and Nominating and Corporate Governance Committees are independent under applicable Nasdaq listing standards; and (ii) all members of the Audit Committee meet the independence requirements under the Exchange Act.

Special Note Regarding Independence of Dr. Papadopoulos. Dr. Papadopoulos is considered a “co-founder” of Exelixis as a result of financial contributions he made during the earliest part of its history and his role in assembling and advising the

Proposal 1 | Corporate Governance

scientists who ultimately served as the company’s earliest management team. However, he has never been employed by us or otherwise involved with any daily business operations and, moreover, Exelixis’ management team today is composed of entirely different individuals from the company’s earliest management team. Accordingly, the Board has determined that Dr. Papadopoulos is independent under applicable SEC rules and the Nasdaq listing standards and is qualified to serve as our Chair and on our Audit Committee, as the Board believes that he has no interest, business or other relationship (including no family relationships) that could, or could reasonably be perceived to, materially interfere with his ability to act in the best interests of Exelixis.

Board Leadership Structure

The Board does not have a formal policy on whether the role of Chair and Chief Executive Officer should be separate or combined. Our Corporate Governance Guidelines provide that the Board will select its Chair and the Chief Executive Officer

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Senior management presents the full Board with frequent business updates during monthly teleconferences, at which time the Board provides management with feedback, makes recommendations and, as needed, issues directives to address our risk exposure.

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Proposal 1 | Corporate Governance

We seek to achieve these commitments through a number of initiatives, including those listed below:

Our Governance and Compliance

Access to Health

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Proposal 1 | Corporate Governance

Taking Responsibility for Our Products

Environmental

Human Capital Management and Workforce Diversity

Further information about our ESG programs and sustainability efforts is available on our website atwww.exelixis.com under the caption “Impact—Environmental, Social and Governance.”

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Proposal 1 | Corporate Governance

Stockholder Communications with the Board

The Board welcomes communications from Exelixis’ stockholders. Stockholders may communicate with the Board by sending a written communication to “Exelixis, Inc., Board of Directors c/o Corporate Secretary, 1851 Harbor Bay Parkway, Alameda, California 94502.” Stockholders may also communicate with the Board by facsimile at(650) 837-7951 or bye-mail at info@exelixis.com, with each of the foregoing sent with “Attn: Board of Directors” in the “Subject” line.

Each communication must set forth the name and address of the stockholder as it appears in the Exelixis’ records (and, if the stock is held by a nominee, the name and address of the beneficial owner of the stock). After confirming the stock ownership of the author of the communication, the Corporate Secretary will review and evaluate the communication, and shall have the authority to and will screen out communications from stockholders that are not directly related to the duties and responsibilities of the Board. The Corporate Secretary may also disregard duplicative communications. If deemed directly related to the duties and responsibilities of the Board, the Corporate Secretary will forward the communication, depending on the subject matter, to the Chair of the Nominating and Corporate Governance Committee, the Chair of the Audit Committee, the Chair of the Board, the independent directors, or the full Board, as deemed appropriate.

Stockholder Outreach

We maintain a robust program for stockholder outreach to elicit a better understanding of the concerns and perspectives of our stockholder base, and we have implemented the feedback received from our stockholders into our executive compensation program, governance practices and other areas of our business. For additional details about our stockholder outreach efforts during fiscal 2019,2020, please see “Compensation Discussion and Analysis—How We Determine Executive Compensation—Stockholder Outreach.”

Stock Ownership Guidelines forNon-Employee Directors

We maintain Stock Ownership Guidelines for our directors and Named Executive Officers (as defined below) to further align their financial interests with those of our stockholders, as well as to promote sound corporate governance. For ournon-employee directors, we amended our Stock Ownership Guidelines in February 2021 to provide an ownership target equalof the value equivalent to 5 times the annual cash Board retainer, an increase from the prior target of the lesser of athe value equivalent to three3 times the annual cash Board retainer or 3,000 shares. Allnon-employee directors are expected to achieve their stock ownership targets within five years of becoming subject to these guidelines. The policy includes procedures for granting exemptions in the case of severe financial hardship. Ownership targets for our Named Executive Officers (including those serving on our Board) are described below under  “Compensation Discussion and Analysis—Other Compensation Information—Stock Ownership Guidelines.”

In determining ownership levels for eachnon-employee director under our Stock Ownership Guidelines, credit is provided for shares held outright (including shares owned through trusts, the Amended and Restated Exelixis, Inc. 401(k) Plan (401(k) Plan), or by a spouse), as well as 50% of the number of vested, but unexercised, stock options. No credit is provided for RSUs (as defined below) until they vest. The values for all shares determined to be held by ournon-employee directors and Named Executive Officers are based on the200-day average stock price as of the measurement date. As of February 10, 2020,5, 2021, all of ournon-employee directors had met the required ownership targets.

Board Committees and Meetings

The Board held seven meetings and acted by unanimous written consent one time during 2019,2020, and all of our directors other than Dr. Scangos attended at least 75% of the total meetings of the Board and of the committees on which they served. Dr. Scangos’ absences were due principally to scheduling conflicts with certain activities and meetings in connection with the initial public offering of Vir Biotechnology, Inc. (Vir), for which Dr. Scangos serves as Chief Executive Officer and as a member of the Vir Board of Directors. In February 2020, Dr. Scangos provided us with notice that he will retire from the Board at the end of his current term, which expires at the Annual Meeting. The independent directors met four times in regularly scheduled executive sessions.

From January 2019 until December 2019,During 2020, the Board had fourfive standing committees: the Audit Committee; the Compensation Committee; the Nominating and Corporate Governance Committee; and the Research & Development Committee; and the Risk Committee. On

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Proposal 1 | Board Committees and Meetings

December 5, 2019, the Board established a Risk Committee to assist the Board in its oversight of management’s responsibility to assess, manage and mitigate risks associated with our business and operational activities. Committee membership in 20192020 was as follows:

Audit Committee

The Audit Committee assists the Board in overseeing our financial reporting process and ensuring the integrity of our financial statements. The Audit Committee is composed entirely of independent directors and performs several functions, including:

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Proposal 1 | Board Committees and Meetings

The Audit Committee’s report is set forth in “Report of the Audit Committee” below. The Audit Committee has a written charter, which is available on our website atwww.exelixis.com under the caption “Investors & Media—Corporate Governance—Committee Composition and Charters.”

Compensation Committee

The Compensation Committee assists the Board in overseeing our compensation policies, plans and programs. The Compensation Committee is composed entirely of independent directors and performs several functions, including:

The Compensation Committee’s report is set forth in “Compensation Committee Report” below. Information on the Compensation Committee’s processes and procedures for consideration of executive compensation are addressed in “Compensation Discussion and Analysis” below. For information regarding our processes and procedures for the consideration and determination of director compensation, please see “Compensation of Directors” below. The Compensation Committee has a written charter, which is available on our website atwww.exelixis.com under the caption “Investors & Media—Corporate Governance—Committee Composition and Charters.” In accordance with its charter, the Compensation Committee also may delegate any of its authority or responsibility to the Chair of the Compensation Committee or to a subcommittee composed of one or more members of the Compensation Committee and/or other members of the Board and/or officers of Exelixis.

Compensation Consultants.The Compensation Committee retained Compensia, Inc. (Compensia),Radford, a national compensation consulting firm serving technology and life sciences companies, as its external compensation consultant to assist the Compensation Committee in its duties related to executive andnon-employee director compensation from March 2019 until November 2019. Compensia did not perform any work for us other than the executive compensation andnon-employee director compensation consulting services provided to the Compensation Committee andduring 2020. In this capacity, Radford reported directly to the Compensation Committee or through its Chair. Fees paid to Compensia in 2019 did not exceed $120,000. Beginning in November 2019, the Compensation Committee retained Radford, a compensation consulting firm serving technology and life sciences companies, to succeed Compensia as the Compensation Committee’s external compensation consultant with respect to future executive andnon-employee director compensation matters. In addition, at the direction of the Compensation Committee, management retained Radford, principally to provide benchmark and industry compensation data for executive and broad-based compensation analyses. In consideration for compensation related services provided during 20192020 we paid Radford an aggregate of $18,176.$219,737. Radford also provided our management with access to the Radford Global Life Sciences Survey, Radford Global Technology Survey, Radford Global Sales Survey, and Radford U.S. Benefits Survey and similar materials, for which we paid Radford an aggregate of $27,405$28,857 in 2019.2020. Radford is an Aon Hewitt company and an affiliate of Aon Risk Services which provided insurance brokerage services to us during 20192020 at a total cost of $205,000. See “Compensation Discussion and Analysis” for more information regarding the Compensation Committee’s engagement of Compensia and Radford.

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Proposal 1 | Board Committees and Meetings

Nominating and Corporate Governance Committee

The Nominating and Corporate Governance Committee oversees all aspects of our corporate governance functions on behalf of the Board. The Nominating and Corporate Governance Committee is composed entirely of independent directors and performs several functions, including:

In addition, as part of its oversight of our governance practices, the Nominating and Corporate Governance Committee oversees management in its preparation of public disclosures pertaining to our ESG programs and sustainability efforts. The Nominating and Corporate Governance Committee has a written charter, which is available on our website atwww.exelixis.com under the caption “Investors & Media—Corporate Governance—Committee Composition and Charters.”

Director Qualifications; Diversity. The Nominating and Corporate Governance Committee does not have a fixed set of minimum qualifications for candidates for membership on the Board. Instead, in considering candidates for directorship, the Nominating and Corporate Governance Committee will generally consider all relevant factors, including the candidate’s applicable expertise and demonstrated excellence in his or her field, the usefulness of such expertise to us, the availability of the candidate to devote sufficient time and attention to the affairs of Exelixis, the existence of any relationship that would interfere with the exercise of the candidate’s independent judgment, and the candidate’s demonstrated character and judgment. In addition, the Board believes that its members should reflect a diversity of viewpoints, background, experience and other characteristics such as gender and race. Accordingly, when evaluating candidates for nomination as new directors, the Nominating and Corporate Governance Committee will seek to considerconsiders (and will ask any search firm that it engages to provide) a set of candidates who would contribute to Board diversity, including both women and individuals from historically underrepresented communities of color who meet the relevant business and search criteria. Both the Nominating and Corporate Governance Committee and full Board evaluate the effectiveness of this diversity policy as part of their periodic performance assessments. In the director candidate review process, the Nominating and Corporate Governance Committee evaluates prospective candidates for directorship in the context of the existing membership of the Board (including the qualities and skills of the existing directors), our operating requirements and the long-term interests of our stockholders.

The Nominating and Corporate Governance Committee regularly evaluates the needs of the Board with respect to skills and experiences that may be filled by a new director candidate. In addition, the Nominating and Corporate Governance Committee is authorized to access external resources as it deems necessary or appropriate to fulfill its defined responsibilities, including engagement of executive search firms to help identify director candidates.

Director Nominations.The Nominating and Corporate Governance Committee considers and assesses all candidates recommended by our directors, officers and stockholders. Evaluations of candidates generally involve a review of background materials, internal discussions and interviews with selected candidates as appropriate. If, after its review, the Nominating and Corporate Governance Committee supports a candidate, it would recommend the candidate for consideration by the full Board. The Nominating and Corporate Governance Committee considers stockholder recommendations for directors using the same criteria as potential nominees recommended by the members of the Nominating and Corporate Governance Committee or others. The Nominating and Corporate Governance Committee has not received any recommended nominations from any stockholder holding 5% or more of our common stock in connection with the Annual Meeting.

Proposal 1 | Board Committees and Meetings

Stockholders who wish to recommend individuals for consideration by the Nominating and Corporate Governance Committee to become nominees for election to the Board may do so by delivering a written recommendation to the Nominating and Corporate Governance Committee within the timeframe specified in our Bylaws that is applicable to matters

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Risk Committee

The Risk Committee of the Board assists the Board in overseeing management’s responsibility to assess, manage and mitigate risks associated with our business and operational activities. The Risk Committee is composed entirely of independent directors and performs several functions, including:

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Compensation of Directors

COMPENSATION OF DIRECTORS

Overview of Director Compensation

The compensation program for ournon-employee directors is intended to be competitive and fair so that we can attract optimal talent to our Board and recognize the time and effort required of a director given the size and complexity of our operations. In accordance with its charter, our Compensation Committee is responsible for recommending to the Board for approval the annual compensation for ournon-employee directors and acts on behalf of the Board in discharging the Board’s responsibilities with respect to overseeing our compensation policies fornon-employee directors. To assist with the Compensation Committee’s and the Board’s review, ourthe Compensation Committee’s external compensation consultant prepares a comprehensive annual assessment of ournon-employee director compensation program. The assessment includes benchmarking director compensation against the same 20192020 peer group used for executive compensation purposes, an update in recent trends in director compensation and a review of related corporate governance best practices.

Recent Changes to Director Compensation

In February 2019, the Board approved changes to thenon-employee director compensation program following consideration of market data prepared by the Compensation Committee’s independent compensation adviser, and the recommendation of the Compensation Committee. The primary goal of these changes was to balance our ability to attract and retain the highest quality directors while aligning the program with the interests of our stockholders. As such, the Board sought to align the total compensation for ournon-employee directors with those in the 60th percentile of our same 2019 peer group used for executive compensation purposes. The Board also sought to ensure that the pay structure appropriately reflected the scope of responsibilities and level of contribution provided by ournon-employee directors. Among the changes to the program in 2019 were the following:

These changes were effective beginning with the first quarter of fiscal 2019.

In addition, at our 2017 Annual Meeting of Stockholders, our stockholders approved a limit on the amount ofnon-employee director compensation under our 2017 Plan. The aggregate value of all compensation granted or paid to any individual solely for service as a non-employee director of the Board of Directors may not exceed (a) $750,000 in total value with respect to any calendar year after a non-employee director is first appointed or elected to the Board or (b) $1,500,000 in total value with respect to the calendar year during which a non-employee director is first appointed or elected to the Board, in each case calculating the value of any stock awards based on the grant date fair value of such awards for financial reporting purposes. This limit was not intended to serve as an increase in the annual amount ofnon-employee director compensation; rather, this action was approved for the purpose of limiting the amount of compensation the Board can approve fornon-employee directors each year.

Cash Compensation Arrangements

Eachnon-employee director receives an annual cash retainer for his or her service on the Board, as well as an additional annual cash retainer if he or she serves as the Chair of the Board, on a committee or as the chair of a committee. In addition, ournon-employee directors receive meeting fees for attendance at each Board meeting or at each of their respective committee meetings in excess of thepre-determined number of meetings for the fiscal year, which is included in the full description of the 20192020 cash compensation arrangements for ournon-employee directors in the table below.

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Equity Compensation Arrangements

Ournon-employee directors are also eligible to receive equity as part of their Board service, including an initial award upon joining the Board and an annual award on the day following each annual meeting of stockholders. Grants to ournon-employee directors are made under our 2017 Equity Incentive Plan (2017 Plan), pursuant to theNon-Employee Director Equity Compensation Policy, as amended (2017 Directors’(Directors’ Policy), as adopted by the Board. To address changes in the trading price of our common stock, we utilize a value-based approach for determining the number of shares subject tonon-employee director equity awards. Under the terms of the 2017 Directors’ Policy, the aggregate value of eachone-time initial award is $680,000, and the aggregate value of each annual award is $400,000. The value of each initial award and annual award is then divided approximately evenly between a nonstatutory stock option and a restricted stock unit (RSU) award. However, effective as of February 2020, eachnon-employee director may instead elect to receive the full value of his or her annual award in the form of either RSUs or nonstatutory stock options.

Under the 2017 Directors’ Policy, the total number of options and RSUs granted as part of each initial award and annual award is determined using a formula based upon the Black-Scholes Merton option pricing model and the average of the daily closing sale prices of our common stock for the trading days during the30-day calendar period ending on (and including) the last calendar day immediately prior to the relevant grant date. The value of each award, as determined in accordance with the 2017 Directors’ Policy, may be greater or lesser than the grant date fair value computed for financial reporting purposes and reflected in the “Director“Director Compensation Table”Table” below. This is a result of the different calculation employed to determine the grant date fair value, which uses a formula based upon the Black-Scholes Merton option pricing model and the closing sale price of our common stock on the grant date.

Options granted under the 2017 Plan in accordance with the 2017 Directors’ Policy are not incentive stock options under the Internal Revenue Code of 1986, as amended (the Code). The exercise price of each initial and annual stock option granted under the 2017 Plan is equal to 100% of the fair market value of a share of common stock on the grant date. Under the terms of the 2017 Directors’ Policy, theone-time initial options are immediately exercisable, but shares issued upon early exercise are subject to a repurchase right and will vest at the rate of 25% of the underlying shares on the first anniversary of the grant date and monthly thereafter over the next three years. The annual options are immediately exercisable, but shares issued upon early exercise are subject to a repurchase right and will vest at the rate of 100% of the underlying shares on the first anniversary of the grant date.

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Compensation of Directors

Director Compensation Table

The following table shows compensation information for ournon-employee directors for the fiscal year ended January 3, 2020.1, 2021.

Director Compensation for Fiscal 20192020

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Proposal 2 | Ratification of Selection of Independent Registered Public Accounting Firm

PROPOSAL 2

RATIFICATIONOF SELECTIONOF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Audit Committee of the Board has selected Ernst & Young LLP as Exelixis’ independent registered public accounting firm for the fiscal year ending January 1,December 31, 2021. The Board, on behalf of the Audit Committee, has further directed that management submit the selection of the independent registered public accounting firm for ratification by the stockholders at the Annual Meeting. Ernst & Young LLP has audited our financial statements for each of the nineteentwenty fiscal years in the period ended January 3, 2020.1, 2021. Representatives of Ernst & Young LLP are expected to be present 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 our Bylaws nor other governing documents or law require stockholder ratification of the selection of Ernst & Young LLP as Exelixis’ independent registered public accounting firm. However, the Board is submitting the selection of Ernst & Young LLP to the stockholders for ratification as a matter of good corporate governance. If the stockholders fail to ratify the selection, the Audit Committee of the Board will reconsider whether or not to retain that firm. Even if the selection is ratified, the Audit Committee of the Board 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 Exelixis and its stockholders.

The affirmative vote of the holders of a majority of the shares present or represented by proxy at the Annual Meeting and entitled to vote at the Annual Meetingon this proposal is required to ratify the selection of Ernst & Young LLP. Abstentions will be counted toward the tabulation of votes cast on proposals presented to the stockholdersthis proposal and will have the same effect as a votevotes against this proposal. Brokers generally have discretionary authority to vote on the ratification of our independent accounting firm; thus, we do not expect any brokerBroker non-votes, on this proposal.if any, will have no effect.

Principal Accountant Fees and Services

The aggregate fees billed by Ernst & Young LLP for the last two fiscal years for the services described below are as follows:

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Proposal 2 | Ratification of Selection of Independent Registered Public Accounting Firm

All fees described above werepre-approved by the Audit Committee. The Audit Committee has determined that the rendering of the services other than audit services by Ernst & Young LLP is compatible with maintaining the independence of the independent registered public accounting firm.

Pre-Approval of Services

During 20192020 and 2018,2019, the Audit Committee of the Boardpre-approved the audit andnon-audit services to be performed by Exelixis’ independent registered public accounting firm, Ernst & Young LLP.Non-audit services are defined as services other than those provided in connection with an audit or a review of our financial statements. The Audit Committeepre-approves all audit andnon-audit services rendered by Ernst & Young LLP. The Audit Committee generallypre-approves specified services in the defined categories of audit services, audit-related services, tax services and all other services up to specified amounts.Pre-approval may also be given as part of the Audit Committee’s approval of the scope of the engagement of the independent registered public accounting firm or on an individual explicitcase-by-case basis before the independent auditor is engaged to provide each service. The Audit Committee or its Chair, whom the Audit Committee has designated as aone-person subcommittee withpre-approval authority,pre-approved all audit fees, audit-related fees, tax fees and other fees in 20192020 and 2018.2019. Anypre-approvals by the subcommittee must be and were presented to the Audit Committee at its next scheduled meeting.

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Report of the Audit Committee

REPORTOFTHE AUDIT COMMITTEE

The material in this report is not “soliciting material,” is not deemed “filed” with the Securities and Exchange Commission and is not deemed to be incorporated by reference in any filing of Exelixis under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date hereof and irrespective of any general incorporation language in any such filing.

In connection with the audited consolidated financial statements for the fiscal year ended January 3, 2020,1, 2021, of Exelixis, Inc. (“Exelixis”), the Audit Committee of the Board of Directors of Exelixis has:

(1) reviewed and discussed the audited financial statements for the fiscal year ended January 3, 2020,1, 2021, with management of Exelixis;

(2) discussed with Ernst & Young LLP, Exelixis’ independent registered public accounting firm (“Ernst & Young”), the matters required to be discussed by the applicable requirements of the Public Company Accounting Oversight Board (“PCAOB”); and the SEC; and

(3) received the written disclosures and the letter from Ernst & Young required by the applicable requirements of the PCAOB regarding Ernst & Young’s communications with the Audit Committee concerning independence, and has discussed with Ernst & Young that accounting firm’s independence.

Based on the foregoing, the Audit Committee has recommended to the Board of Directors that the audited financial statements be included in Exelixis’ Annual Report on Form10-K for the fiscal year ended January 3, 2020.1, 2021.

Audit Committee:

Jack L. Wyszomierski, Chair

Charles Cohen

Stelios Papadopoulos

Julie A. Smith

32    Exelixis, Inc.

Proposal 3 | Amendment and Restatement of 2017 Equity Incentive Plan

PROPOSAL 3

AMENDMENTAND RESTATEMENTOF 2017 EQUITY INCENTIVE PLAN

The Compensation Committee approved an amendment and restatement of the 2017 Plan in March 2020, subject to approval by our stockholders. For purposes of this Proposal 3, we refer to the 2017 Plan, as amended and restated by the Compensation Committee in March 2020, as the “Amended 2017 Plan.” We are asking our stockholders to approve the Amended 2017 Plan at the Annual Meeting.

The Amended 2017 Plan contains the following material changes from the 2017 Plan:

Why We Are Asking Our Stockholders to Approve the Amended 2017 Plan

We are seeking stockholder approval of the Amended 2017 Plan to increase the number of shares available for the grant of stock options, RSU awards and other awards to our employees and directors, which will enable us to have a competitive equity incentive program to compete with our peer group for key talent.

Approval of the Amended 2017 Plan by our stockholders will allow us to continue to grant stock options and RSU awards at levels determined appropriate by the Board or Compensation Committee, which determination takes into account the impact of such awards on stockholder dilution. The Amended 2017 Plan will also allow us to utilize a broad array of equity incentives in order to secure and retain the services of our employees and directors, and to provide long-term incentives that align the interests of our employees and directors with the interests of our stockholders.

Requested Share Increase

Subject to adjustment for certain changes in our capitalization, if this Proposal 3 is approved by our stockholders, we will have 21,000,000 new shares available for grant under the Amended 2017 Plan after the Annual Meeting.

Due to the inherent unpredictability of clinical trial outcomes and of regulatory approval processes, we are not presently able to forecast the rate at which we will utilize equity awards as a tool for attracting and retaining talent. Taking these factors into consideration, the Board determined that our request for 21,000,000 new shares under the Amended 2017 Plan is an appropriate amount that we believe a majority of our institutional investors would support.

Why You Should Vote to Approve the Amended 2017 Plan

Equity Awards Are an Important Part of Our Compensation Philosophy

The Board believes that our future success depends, in large part, on our ability to maintain a competitive position in attracting, retaining and motivating employees and directors. The Board believes that the grant of equity awards is a key element underlying our ability to attract, retain and motivate employees and directors, and better aligns the interests of our employees and directors with those of our stockholders. The Amended 2017 Plan will allow us to continue to provide equity-based incentives to our employees and directors. Therefore, the Board believes that the Amended 2017 Plan is in the best interests of Exelixis and our stockholders and recommends a vote in favor of this Proposal 3.

2020 Proxy Statement    33