<SEC-DOCUMENT>0000939767-17-000148.txt : 20170914
<SEC-HEADER>0000939767-17-000148.hdr.sgml : 20170914
<ACCEPTANCE-DATETIME>20170914191716
ACCESSION NUMBER:		0000939767-17-000148
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170912
FILED AS OF DATE:		20170914
DATE AS OF CHANGE:		20170914

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Senner Christopher J.
		CENTRAL INDEX KEY:			0001648367

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30235
		FILM NUMBER:		171086598

	MAIL ADDRESS:	
		STREET 1:		210 EAST GRAND AVE.
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EXELIXIS, INC.
		CENTRAL INDEX KEY:			0000939767
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMMERCIAL PHYSICAL & BIOLOGICAL RESEARCH [8731]
		IRS NUMBER:				043257395
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0102

	BUSINESS ADDRESS:	
		STREET 1:		210 E. GRAND AVE
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080
		BUSINESS PHONE:		6508377000

	MAIL ADDRESS:	
		STREET 1:		210 E. GRAND AVE
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	EXELIXIS INC
		DATE OF NAME CHANGE:	20000207

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	EXELIXIS PHARMACEUTICALS INC
		DATE OF NAME CHANGE:	20000106
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_150543102162859.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-09-12</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000939767</issuerCik>
        <issuerName>EXELIXIS, INC.</issuerName>
        <issuerTradingSymbol>EXEL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001648367</rptOwnerCik>
            <rptOwnerName>Senner Christopher J.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O EXELIXIS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>210 EAST GRAND AVE.</rptOwnerStreet2>
            <rptOwnerCity>SOUTH SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94080</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP and CFO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-09-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>100000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.66</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>202759</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-09-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>100000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>26.79</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>102759</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2039</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401(k)</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.66</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-09-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>100000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2016-07-15</value>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2022-07-14</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>100000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>250000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Includes 20,000 shares of Exelixis, Inc. common stock that will be issued to the Reporting Person upon vesting of restricted stock units and 2,361 shares of common stock acquired pursuant to the Exelixis, Inc. 2000 Employee Stock Purchase Plan on April 28, 2017.</footnote>
        <footnote id="F2">Represents 2,039 shares of Exelixis, Inc. common stock under the Exelixis, Inc. 401(k) Plan, pursuant to a plan statement dated as of September 12, 2017.</footnote>
        <footnote id="F3">The option, representing the right to purchase a total of 350,000 shares of Exelixis, Inc. common stock, was exercisable as to 182,291 shares on the Transaction Date. Th remainder of the option will vest as to 1/48th of the original number of shares subject to the option on each monthly anniversary of July 15, 2015 grant date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Jeffrey J. Hessekiel, Attorney in Fact</signatureName>
        <signatureDate>2017-09-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
