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    ACCESSION NUMBER:		0001193125-21-358541
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		21
    CONFORMED PERIOD OF REPORT:	20211216
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Other Events
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20211216
    DATE AS OF CHANGE:		20211216

    FILER:

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

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    		SEC ACT:		1934 Act
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    		FILM NUMBER:		211495990

    	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
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