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      <issuerAddress>
        <com:street1>99 WALL STREET</com:street1>
        <com:street2>#1950</com:street2>
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        <com:stateOrCountry>NY</com:stateOrCountry>
        <com:zipCode>10005</com:zipCode>
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      <issuerContactPhone>(646) 278-4871</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Utzschneider Lisa</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
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    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Fidelity Brokerage Services LLC</name>
        <address>
          <com:street1>900 Salem Street</com:street1>
          <com:city>Smithfield</com:city>
          <com:stateOrCountry>RI</com:stateOrCountry>
          <com:zipCode>02917</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>35310</noOfUnitsSold>
      <aggregateMarketValue>623984.20</aggregateMarketValue>
      <noOfUnitsOutstanding>154927770</noOfUnitsOutstanding>
      <approxSaleDate>05/23/2023</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
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      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>05/19/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>35310</amountOfSecuritiesAcquired>
      <paymentDate>05/19/2023</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
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    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
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        <name>Lisa M. Utzschneider</name>
        <address>
          <com:street1>99 Wall Street</com:street1>
          <com:street2>#1950</com:street2>
          <com:city>New York</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10005</com:zipCode>
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      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>05/22/2023</saleDate>
      <amountOfSecuritiesSold>27287</amountOfSecuritiesSold>
      <grossProceeds>474927.51</grossProceeds>
    </securitiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>05/23/2023</noticeDate>
      <signature>/s/Wade Moss, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Lisa M Utzschneider</signature>
    </noticeSignature>
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144
0001651659
XXXXXXXX
LIVE
0001842718
INTEGRAL AD SCIENCE HOLDING CORP.
001-40557
99 WALL STREET
#1950
NEW YORK
NY
10005
(646) 278-4871
Utzschneider Lisa
Officer
Common
Fidelity Brokerage Services LLC
900 Salem Street
Smithfield
RI
02917
35310
623984.20
154927770
05/23/2023
NASDAQ
Common
05/19/2023
Restricted Stock Vesting
Issuer
N
35310
05/19/2023
Compensation
N
Lisa M. Utzschneider
99 Wall Street
#1950
New York
NY
10005
Common
05/22/2023
27287
474927.51
05/23/2023
/s/Wade Moss, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Lisa M Utzschneider