<SEC-DOCUMENT>0000899243-20-013636.txt : 20200519
<SEC-HEADER>0000899243-20-013636.hdr.sgml : 20200519
<ACCEPTANCE-DATETIME>20200519204632
ACCESSION NUMBER:		0000899243-20-013636
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200513
FILED AS OF DATE:		20200519
DATE AS OF CHANGE:		20200519

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DAWES KAREN A
		CENTRAL INDEX KEY:			0001261506

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14656
		FILM NUMBER:		20895472

	MAIL ADDRESS:	
		STREET 1:		579 BELLEVUE AVE
		CITY:			NEWPORT
		STATE:			RI
		ZIP:			02840

ISSUER:		

	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

	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
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
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        <issuerTradingSymbol>RGEN</issuerTradingSymbol>
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    <derivativeTable>
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            <transactionDate>
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            <transactionTimeliness>
                <value></value>
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            <transactionAmounts>
                <transactionShares>
                    <value>1761</value>
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                <transactionPricePerShare>
                    <value>0.00</value>
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            <exerciseDate>
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    <footnotes>
        <footnote id="F1">Ms. Dawes was awarded 722 restricted stock units. Each restricted stock unit represents a contingent right to receive one share of Repligen Corporation's Common Stock. The restricted stock units vest on May 13, 2021. The restricted stock units may be settled only by delivering shares of Repligen Corporation's Common Stock, and thus, the grant is being reported in Table I as allowed per SEC guidance.</footnote>
        <footnote id="F2">Sale of common stock was effected pursuant to a 10(b)5-1 trading plan adopted on February 19, 2020.</footnote>
        <footnote id="F3">$135.76 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $135.26 to $136.19, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F4">$138.60 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $137.94 to $138.84, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F5">$139.32 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $139.11 to $139.44, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F6">$140.62 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $140.21 to $140.89, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F7">$141.45 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $141.42 to $142.01, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F8">Award vests in full one year from grant date on May 13, 2021.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Jeffrey P. Leduc (Attorney in Fact)</signatureName>
        <signatureDate>2020-05-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
