<SEC-DOCUMENT>0001959173-25-006318.txt : 20251003
<SEC-HEADER>0001959173-25-006318.hdr.sgml : 20251003
<ACCEPTANCE-DATETIME>20251003114441
ACCESSION NUMBER:		0001959173-25-006318
CONFORMED SUBMISSION TYPE:	144
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20251003
DATE AS OF CHANGE:		20251003

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			INTEGRAL AD SCIENCE HOLDING CORP.
		CENTRAL INDEX KEY:			0001842718
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMPUTER PROGRAMMING, DATA PROCESSING, ETC. [7370]
		ORGANIZATION NAME:           	06 Technology
		EIN:				830731995
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		144
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	001-40557
		FILM NUMBER:		251372605

	BUSINESS ADDRESS:	
		STREET 1:		12 EAST 49TH STREET
		STREET 2:		20TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
		BUSINESS PHONE:		(646) 278-4871

	MAIL ADDRESS:	
		STREET 1:		12 EAST 49TH STREET
		STREET 2:		20TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTEGRAL AD SCIENCE HOLDING LLC
		DATE OF NAME CHANGE:	20210301

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	KAVACHA TOPCO, LLC
		DATE OF NAME CHANGE:	20210127

REPORTING-OWNER:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Gil Alexis II
		CENTRAL INDEX KEY:			0002001306
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		144

	MAIL ADDRESS:	
		STREET 1:		12 EAST 49TH STREET
		STREET 2:		FLOOR 20
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10017
</SEC-HEADER>
<DOCUMENT>
<TYPE>144
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
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    <submissionType>144</submissionType>
    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0002001306</cik>
          <ccc>XXXXXXXX</ccc>
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      <liveTestFlag>LIVE</liveTestFlag>



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    <issuerInfo>
      <issuerCik>0001842718</issuerCik>
      <issuerName>INTEGRAL AD SCIENCE HOLDING CORP.</issuerName>
      <secFileNumber>001-40557</secFileNumber>
      <issuerAddress>
        <com:street1>12 EAST 49TH STREET</com:street1>
        <com:street2>20TH FLOOR</com:street2>
        <com:city>NEW YORK</com:city>
        <com:stateOrCountry>NY</com:stateOrCountry>
        <com:zipCode>10017</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>(646) 278-4871</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Gil Alexis II</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <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>3527</noOfUnitsSold>
      <aggregateMarketValue>35904.86</aggregateMarketValue>
      <noOfUnitsOutstanding>166163514</noOfUnitsOutstanding>
      <approxSaleDate>10/03/2025</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>10/01/2025</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>3527</amountOfSecuritiesAcquired>
      <paymentDate>10/01/2025</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alexis Gil II</name>
        <address>
          <com:street1>12 E 49th Street</com:street1>
          <com:street2>20th Floor</com:street2>
          <com:city>New York</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10017</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>07/07/2025</saleDate>
      <amountOfSecuritiesSold>1962</amountOfSecuritiesSold>
      <grossProceeds>16539.47</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alexis Gil II</name>
        <address>
          <com:street1>12 E 49th Street</com:street1>
          <com:street2>20th Floor</com:street2>
          <com:city>New York</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10017</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>09/03/2025</saleDate>
      <amountOfSecuritiesSold>2784</amountOfSecuritiesSold>
      <grossProceeds>24995.59</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alexis Gil II</name>
        <address>
          <com:street1>12 E 49th Street</com:street1>
          <com:street2>20th Floor</com:street2>
          <com:city>New York</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10017</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>09/24/2025</saleDate>
      <amountOfSecuritiesSold>25901</amountOfSecuritiesSold>
      <grossProceeds>263771.71</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Alexis Gil II</name>
        <address>
          <com:street1>12 E 49th Street</com:street1>
          <com:street2>20th Floor</com:street2>
          <com:city>New York</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10017</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>10/02/2025</saleDate>
      <amountOfSecuritiesSold>1992</amountOfSecuritiesSold>
      <grossProceeds>20280.15</grossProceeds>
    </securitiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>10/03/2025</noticeDate>
      <planAdoptionDates>
        <planAdoptionDate>06/12/2025</planAdoptionDate>
      </planAdoptionDates>
      <signature>/s/Wade Moss, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Alexis Gil II</signature>
    </noticeSignature>
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</SEC-DOCUMENT>
