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        <issuerName>FACTSET RESEARCH SYSTEMS INC</issuerName>
        <secFileNumber>001-11869</secFileNumber>
        <issuerAddress>
          <com:street1>45 GLOVER AVENUE</com:street1>
          <com:city>NORWALK</com:city>
          <com:stateOrCountry>CT</com:stateOrCountry>
          <com:zipCode>06850</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>2038101000</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Snow Frederick Philip</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</relationshipToIssuer>
        </relationshipsToIssuer>
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      <securitiesInformation>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Fidelity Brokerage Services LLC</name>
          <address>
            <com:street1>245 Summer Street</com:street1>
            <com:city>Boston</com:city>
            <com:stateOrCountry>MA</com:stateOrCountry>
            <com:zipCode>02110</com:zipCode>
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        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>3000</noOfUnitsSold>
        <aggregateMarketValue>1365270.00</aggregateMarketValue>
        <noOfUnitsOutstanding>38039989</noOfUnitsOutstanding>
        <approxSaleDate>10/01/2024</approxSaleDate>
        <securitiesExchangeName>NYSE</securitiesExchangeName>
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      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>10/01/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>FactSet Research Systems Inc.</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>3000</amountOfSecuritiesAcquired>
        <paymentDate>10/01/2024</paymentDate>
        <natureOfPayment>Wire</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
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          <name>Frederick Philip Snow</name>
          <address>
            <com:street1>c/o FACTSET RESEARCH SYSTEMS INC.</com:street1>
            <com:street2>45 Glover Avenue</com:street2>
            <com:city>Norwalk</com:city>
            <com:stateOrCountry>CT</com:stateOrCountry>
            <com:zipCode>06850</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <saleDate>07/01/2024</saleDate>
        <amountOfSecuritiesSold>3000</amountOfSecuritiesSold>
        <grossProceeds>1226940.00</grossProceeds>
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        <sellerDetails>
          <name>Frederick Philip Snow</name>
          <address>
            <com:street1>c/o FACTSET RESEARCH SYSTEMS INC.</com:street1>
            <com:street2>45 Glover Avenue</com:street2>
            <com:city>Norwalk</com:city>
            <com:stateOrCountry>CT</com:stateOrCountry>
            <com:zipCode>06850</com:zipCode>
          </address>
        </sellerDetails>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <saleDate>08/01/2024</saleDate>
        <amountOfSecuritiesSold>3000</amountOfSecuritiesSold>
        <grossProceeds>1238250.00</grossProceeds>
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            <com:zipCode>06850</com:zipCode>
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        </sellerDetails>
        <securitiesClassTitle>Common Stock	</securitiesClassTitle>
        <saleDate>09/03/2024</saleDate>
        <amountOfSecuritiesSold>3000</amountOfSecuritiesSold>
        <grossProceeds>1249770.00</grossProceeds>
      </securitiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>10/01/2024</noticeDate>
        <planAdoptionDates>
          <planAdoptionDate>09/27/2023</planAdoptionDate>
        </planAdoptionDates>
        <signature>/s/ Audrey Skillern, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Frederick Philip Snow</signature>
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text: 144
  0001611324
  XXXXXXXX
  LIVE
  0001013237
  FACTSET RESEARCH SYSTEMS INC
  001-11869
  45 GLOVER AVENUE
  NORWALK
  CT
  06850
  2038101000
  Snow Frederick Philip
  Officer
  Common Stock
  Fidelity Brokerage Services LLC
  245 Summer Street
  Boston
  MA
  02110
  3000
  1365270.00
  38039989
  10/01/2024
  NYSE
  Common Stock
  10/01/2024
  Stock Option Exercise
  FactSet Research Systems Inc.
  N
  3000
  10/01/2024
  Wire
  N
  Frederick Philip Snow
  c/o FACTSET RESEARCH SYSTEMS INC.
  45 Glover Avenue
  Norwalk
  CT
  06850
  Common Stock
  07/01/2024
  3000
  1226940.00
  Frederick Philip Snow
  c/o FACTSET RESEARCH SYSTEMS INC.
  45 Glover Avenue
  Norwalk
  CT
  06850
  Common Stock
  08/01/2024
  3000
  1238250.00
  Frederick Philip Snow
  c/o FACTSET RESEARCH SYSTEMS INC.
  45 Glover Avenue
  Norwalk
  CT
  06850
  Common Stock
  09/03/2024
  3000
  1249770.00
  10/01/2024
  09/27/2023
  /s/ Audrey Skillern, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Frederick Philip Snow