<SEC-DOCUMENT>0001193125-17-005121.txt : 20170405
<SEC-HEADER>0001193125-17-005121.hdr.sgml : 20170405
<ACCEPTANCE-DATETIME>20170109073055
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ACCESSION NUMBER:		0001193125-17-005121
CONFORMED SUBMISSION TYPE:	CORRESP
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20170109

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

	FILING VALUES:
		FORM TYPE:		CORRESP

	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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<DOCUMENT>
<TYPE>CORRESP
<SEQUENCE>1
<FILENAME>filename1.htm
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">January&nbsp;9, 2017 </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B><U>Via EDGAR </U></B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Securities and Exchange Commission
</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Division of Corporation Finance </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">100 F Street, N.E. </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Washington, DC 20549-3720 </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><B>RE:</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Repligen Corporation</B> </TD></TR></TABLE> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:8%; font-size:10pt; font-family:Times New Roman"><B>Form 10-K for year ended December&nbsp;31, 2015 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:8%; font-size:10pt; font-family:Times New Roman"><B>Filed February&nbsp;25, 2016 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:8%; font-size:10pt; font-family:Times New Roman"><B>File No. 0-14656 </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Ladies and Gentlemen:
</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Repligen Corporation (the &#147;<U>Company</U>&#148;) hereby advises the staff (the &#147;<U>Staff</U>&#148;) of the Securities and
Exchange Commission (the &#147;<U>Commission</U>&#148;) that the Company has received the Staff&#146;s letter dated December&nbsp;22, 2016 (the &#147;<U>Comment Letter</U>&#148;), regarding the Commission&#146;s review of the Company&#146;s Annual
Report on Form 10-K for the fiscal year ended December&nbsp;31, 2015. The Comment Letter requests that the Company respond within ten (10)&nbsp;business days from the date thereof, or inform the Staff of when the Company would provide a response.
The Company respectfully requests an extension of an additional ten (10)&nbsp;business days until January&nbsp;24, 2017 to respond to the Comment Letter in order to provide sufficient time for the Company to prepare the necessary response. The
Company is committed to responding to the Comment Letter promptly and intends to provide a response to the Staff no later than January&nbsp;24, 2017. Should you have any questions regarding the request made herein, please do not hesitate to contact
me at (781)&nbsp;419-1862. Thank you very much for your courtesy and cooperation in this matter. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
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<TD VALIGN="top">Sincerely,</TD></TR>
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<TD HEIGHT="16"></TD></TR>
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<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Jon Snodgres</P></TD></TR>
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<TD VALIGN="top">Jon Snodgres</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Chief Financial Officer</TD></TR>
</TABLE></DIV> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left">cc:</TD>
<TD ALIGN="left" VALIGN="top">Arthur R. McGivern &#150; Goodwin Procter LLP </TD></TR></TABLE>
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