<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:ns2="http://www.sec.gov/edgar/common">
    <headerData>
        <submissionType>144</submissionType>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001599803</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <issuerInfo>
            <issuerCik>0000939767</issuerCik>
            <issuerName>EXELIXIS INC</issuerName>
            <secFileNumber>000-30235</secFileNumber>
            <issuerAddress>
                <ns2:street1>1851 Harbor Bay Parkway </ns2:street1>
                <ns2:city>Alameda</ns2:city>
                <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                <ns2:zipCode>94502</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>6508377000</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>JEFFREY J HESSEKIEL</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>100000</noOfUnitsSold>
            <aggregateMarketValue>2345000.00</aggregateMarketValue>
            <noOfUnitsOutstanding>285251725</noOfUnitsOutstanding>
            <approxSaleDate>08/07/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>08/07/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of Stock Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>100000</amountOfSecuritiesAcquired>
            <paymentDate>08/07/2024</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <remarks>The securities to be sold were and will be received upon the exercise of stock options over the next three months. The dates of acquisition and payment were and will be the dates of exercise/sale.&#13;
</remarks>
        <noticeSignature>
            <noticeDate>08/07/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>02/28/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Jeffrey J Hessekiel</signature>
        </noticeSignature>
    </formData>
</edgarSubmission>
[{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 3543}]
144
0001599803
XXXXXXXX
LIVE
0000939767
EXELIXIS INC
000-30235
1851 Harbor Bay Parkway
Alameda
CA
94502
6508377000
JEFFREY J HESSEKIEL
Officer
COMMON
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
100000
2345000.00
285251725
08/07/2024
NASDAQ
Common
08/07/2024
Exercise of Stock Options
Issuer
N
100000
08/07/2024
Cash
Y
The securities to be sold were and will be received upon the exercise of stock options over the next three months. The dates of acquisition and payment were and will be the dates of exercise/sale.
08/07/2024
02/28/2024
/s/ Jeffrey J Hessekiel