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      <filer>
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          <ccc>XXXXXXXX</ccc>
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      <liveTestFlag>LIVE</liveTestFlag>



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    <issuerInfo>
      <issuerCik>0000814547</issuerCik>
      <issuerName>FAIR ISAAC CORP</issuerName>
      <secFileNumber>001-11689</secFileNumber>
      <issuerAddress>
        <com:street1>5 WEST MENDENHALL</com:street1>
        <com:street2>SUITES 105</com:street2>
        <com:city>BOZEMAN</com:city>
        <com:stateOrCountry>MT</com:stateOrCountry>
        <com:zipCode>59715</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>(406) 982-7276</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>DEAL RICHARD</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Charles Schwab Corp</name>
        <address>
          <com:street1>3000 Schwab Way</com:street1>
          <com:city>Westlake</com:city>
          <com:stateOrCountry>TX</com:stateOrCountry>
          <com:zipCode>76262</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>13591</noOfUnitsSold>
      <aggregateMarketValue>18877899.00</aggregateMarketValue>
      <noOfUnitsOutstanding>24710938</noOfUnitsOutstanding>
      <approxSaleDate>06/12/2024</approxSaleDate>
      <securitiesExchangeName>NYSE</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/08/2018</acquiredDate>
      <natureOfAcquisitionTransaction>Vested Grants</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>13591</amountOfSecuritiesAcquired>
      <paymentDate>12/08/2018</paymentDate>
      <natureOfPayment>Equity Compensation</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <remarks>Shares sold from The Richard S. Deal Revocable Trust U/A DTD 12/17/2019</remarks>
    <noticeSignature>
      <noticeDate>06/12/2024</noticeDate>
      <signature>RIchard Deal</signature>
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144
0001205411
XXXXXXXX
LIVE
0000814547
FAIR ISAAC CORP
001-11689
5 WEST MENDENHALL
SUITES 105
BOZEMAN
MT
59715
(406) 982-7276
DEAL RICHARD
Officer
Common
Charles Schwab Corp
3000 Schwab Way
Westlake
TX
76262
13591
18877899.00
24710938
06/12/2024
NYSE
Common
12/08/2018
Vested Grants
Issuer
N
13591
12/08/2018
Equity Compensation
Y
Shares sold from The Richard S. Deal Revocable Trust U/A DTD 12/17/2019
06/12/2024
RIchard Deal