<SEC-DOCUMENT>0000080255-25-000176.txt : 20250214
<SEC-HEADER>0000080255-25-000176.hdr.sgml : 20250214
<ACCEPTANCE-DATETIME>20250214094409
ACCESSION NUMBER:		0000080255-25-000176
CONFORMED SUBMISSION TYPE:	SCHEDULE 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20250214
DATE AS OF CHANGE:		20250214

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			REPLIGEN CORP
		CENTRAL INDEX KEY:			0000730272
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		ORGANIZATION NAME:           	03 Life Sciences
		IRS NUMBER:				042729386
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SCHEDULE 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-38071
		FILM NUMBER:		25624039

	BUSINESS ADDRESS:	
		STREET 1:		41 SEYON STREET
		STREET 2:		BUILDING 1, SUITE 100
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02453
		BUSINESS PHONE:		7814499560

	MAIL ADDRESS:	
		STREET 1:		41 SEYON STREET
		STREET 2:		BUILDING 1, SUITE 100
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02453

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PRICE T ROWE ASSOCIATES INC /MD/
		CENTRAL INDEX KEY:			0000080255
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY & COMMODITY BROKERS, DEALERS, EXCHANGES & SERVICES [6200]
		ORGANIZATION NAME:           	09 Crypto Assets
		IRS NUMBER:				520556948
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SCHEDULE 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		100 EAST PRATT ST
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21202
		BUSINESS PHONE:		(410)345-2000

	MAIL ADDRESS:	
		STREET 1:		P.O. BOX 89000
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21289
</SEC-HEADER>
<DOCUMENT>
<TYPE>SCHEDULE 13G/A
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/schedule13g" xmlns:ns2="http://www.sec.gov/edgar/common">
    <headerData>
        <submissionType>SCHEDULE 13G/A</submissionType>
        <previousAccessionNumber>0000080255-22-001963</previousAccessionNumber>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0000080255</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>


        </filerInfo>
    </headerData>
    <formData>
        <coverPageHeader>
            <amendmentNo>5</amendmentNo>
            <securitiesClassTitle>COMMON STOCK</securitiesClassTitle>
            <eventDateRequiresFilingThisStatement>12/31/2024</eventDateRequiresFilingThisStatement>
            <issuerInfo>
                <issuerCik>0000730272</issuerCik>
                <issuerName>REPLIGEN CORP</issuerName>
                <issuerCusip>759916109</issuerCusip>
                <issuerPrincipalExecutiveOfficeAddress>
                    <ns2:street1>41 SEYON STREET</ns2:street1>
                    <ns2:street2>BUILDING, SUITE 100</ns2:street2>
                    <ns2:city>WALTHAM</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02453</ns2:zipCode>
                </issuerPrincipalExecutiveOfficeAddress>
            </issuerInfo>
            <designateRulesPursuantThisScheduleFiled>
                <designateRulePursuantThisScheduleFiled>Rule 13d-1(b)</designateRulePursuantThisScheduleFiled>
            </designateRulesPursuantThisScheduleFiled>
        </coverPageHeader>
        <coverPageHeaderReportingPersonDetails>

            <reportingPersonName>T. Rowe Price Associates, Inc.</reportingPersonName>
            <citizenshipOrOrganization>MD</citizenshipOrOrganization>
            <reportingPersonBeneficiallyOwnedNumberOfShares>
                <soleVotingPower>6445000</soleVotingPower>
                <sharedVotingPower>0</sharedVotingPower>
                <soleDispositivePower>7136086</soleDispositivePower>
                <sharedDispositivePower>0</sharedDispositivePower>
            </reportingPersonBeneficiallyOwnedNumberOfShares>
            <reportingPersonBeneficiallyOwnedAggregateNumberOfShares>7136086</reportingPersonBeneficiallyOwnedAggregateNumberOfShares>
            <aggregateAmountExcludesCertainSharesFlag>N</aggregateAmountExcludesCertainSharesFlag>
            <classPercent>12.7</classPercent>
            <typeOfReportingPerson>IA</typeOfReportingPerson>
        </coverPageHeaderReportingPersonDetails>
        <items>
            <item1>
                <issuerName>REPLIGEN CORP</issuerName>
                <issuerPrincipalExecutiveOfficeAddress>41 SEYON STREET, BUILDING, SUITE 100, WALTHAM, MA, 02453</issuerPrincipalExecutiveOfficeAddress>
            </item1>
            <item2>
                <filingPersonName>T. Rowe Price Associates, Inc.</filingPersonName>
                <principalBusinessOfficeOrResidenceAddress>100 E. Pratt Street, Baltimore, MD 21202</principalBusinessOfficeOrResidenceAddress>
                <citizenship>Maryland</citizenship>
            </item2>
            <item3>
                <notApplicableFlag>N</notApplicableFlag>
                <typeOfPersonFiling>IA</typeOfPersonFiling>
            </item3>
            <item4>
                <amountBeneficiallyOwned>7136086</amountBeneficiallyOwned>
                <classPercent>12.7</classPercent>
                <numberOfSharesPersonHas>
                    <solePowerOrDirectToVote>6445000</solePowerOrDirectToVote>
                    <sharedPowerOrDirectToVote>0</sharedPowerOrDirectToVote>
                    <solePowerOrDirectToDispose>7136086</solePowerOrDirectToDispose>
                    <sharedPowerOrDirectToDispose>0</sharedPowerOrDirectToDispose>
                </numberOfSharesPersonHas>
            </item4>
            <item5>
                <notApplicableFlag>Y</notApplicableFlag>
            </item5>
            <item6>
                <notApplicableFlag>Y</notApplicableFlag>
            </item6>
            <item7>
                <notApplicableFlag>Y</notApplicableFlag>
            </item7>
            <item8>
                <notApplicableFlag>Y</notApplicableFlag>
            </item8>
            <item9>
                <notApplicableFlag>Y</notApplicableFlag>
            </item9>
            <item10>
                <notApplicableFlag>N</notApplicableFlag>
                <certifications>By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11. T. Rowe Price Associates, Inc. hereby declares and affirms that the filing of Schedule 13G shall not be construed as an admission that Price Associates is the beneficial owner of the securities referred to, which beneficial ownership is expressly denied.</certifications>
            </item10>
        </items>
        <signatureInformation>
            <reportingPersonName>T. Rowe Price Associates, Inc.</reportingPersonName>
            <signatureDetails>
                <signature>Ellen York</signature>
                <title>Vice President</title>
                <date>02/14/2025</date>
            </signatureDetails>
        </signatureInformation>
    </formData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
