<SEC-DOCUMENT>0001193125-25-044191.txt : 20250303
<SEC-HEADER>0001193125-25-044191.hdr.sgml : 20250303
<ACCEPTANCE-DATETIME>20250303164540
ACCESSION NUMBER:		0001193125-25-044191
CONFORMED SUBMISSION TYPE:	NT 10-K
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20241231
FILED AS OF DATE:		20250303
DATE AS OF CHANGE:		20250303
EFFECTIVENESS DATE:		20250303

FILER:

	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:		NT 10-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14656
		FILM NUMBER:		25698802

	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>NT 10-K
<SEQUENCE>1
<FILENAME>d812625dnt10k.htm
<DESCRIPTION>NT 10-K
<TEXT>
<HTML><HEAD>
<TITLE>NT 10-K</TITLE>
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<Center><DIV STYLE="width:8.5in" align="left">
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<TD VALIGN="top" COLSPAN="3" ALIGN="center" STYLE="BORDER:1px solid #000000; padding-left:8pt; padding-right:2pt">OMB APPROVAL</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">OMB&nbsp;Number:</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt"><FONT STYLE="white-space:nowrap">3235-0058</FONT></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">Expires:</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt">April&nbsp;30,&nbsp;2025</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3" STYLE="BORDER-LEFT:1px solid #000000; BORDER-RIGHT:1px solid #000000; padding-left:8pt; padding-right:2pt">Estimated&nbsp;average&nbsp;burden</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt">hours&nbsp;per&nbsp;response</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right" STYLE="BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-right:2pt">2.50</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3" ALIGN="center" STYLE="BORDER-LEFT:1px solid #000000; BORDER-RIGHT:1px solid #000000; padding-left:8pt; padding-right:2pt">
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">SEC FILE NUMBER</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">000-14656</P></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
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<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">CUSIP NUMBER</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">759916109</P></TD></TR>
</TABLE></DIV> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Washington, D.C. 20549 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM <FONT
STYLE="white-space:nowrap">12b-25</FONT> </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>NOTIFICATION
OF LATE FILING </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="right"><I>(Check one):&#8195;</I></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">&#9746;&#8194;Form 10-K&#8195; &#9744;&#8194;Form 20-F&#8195; &#9744;&#8194;Form 11-K</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">&#9744;&#8194;Form 10-Q&#8195; &#9744;&#8194;Form 10-D&#8195; &#9744;&#8194;Form N-CEN &#8195;&#9744;&#8194;Form N-CSR</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">For Period Ended: December&nbsp;31, 2024</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;&#8194;Transition Report on Form 10-K</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;&#8194;Transition Report on Form 20-F</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;&#8194;Transition Report on Form 11-K</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;&#8194;Transition Report on Form 10-Q</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">For the Transition Period Ended: <U>&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;&#8195;</U></TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR STYLE="font-size:1pt">
<TD HEIGHT="4" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-RIGHT:1px solid #000000; padding-left:8pt">&nbsp;</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-LEFT:1px solid #000000; BORDER-RIGHT:1px solid #000000; BORDER-BOTTOM:1px solid #000000; padding-left:8pt; padding-right:2pt">
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Nothing in this form shall be construed to imply that the Commission has verified any information contained herein.</B></P>
<P STYLE="font-size:3pt; margin-top:0pt; margin-bottom:1pt" align="left">&nbsp;</P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">If the notification relates to a portion of the filing checked above, identify the Item(s) to which the notification relates:
</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">&#8195; </P>
<P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.50pt solid #000000">&nbsp;</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART I &#151; REGISTRANT
INFORMATION </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:22pt; font-family:Times New Roman" ALIGN="center"><B>Repligen Corporation </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Full Name of Registrant </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Not applicable </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Former
Name if Applicable </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>41 Seyon Street </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Address of Principal Executive Office (Street and Number) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Waltham, Massachusetts 02453 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>City, State and Zip Code </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top">SEC 1344 <FONT STYLE="white-space:nowrap">(01-19)</FONT></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Potential persons who are to respond to the collection of information contained in this Form are not required to respond unless the Form displays a currently valid OMB control number.</TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.50pt solid #000000">&nbsp;</P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART II &#151; RULES <FONT STYLE="white-space:nowrap">12b-25(b)</FONT> AND (c) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">If the subject report could not be filed without unreasonable effort or expense and the registrant seeks relief pursuant to Rule <FONT
STYLE="white-space:nowrap">12b-25(b),</FONT> the following should be completed. (Check box if appropriate) </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="middle" ROWSPAN="3" STYLE="BORDER-RIGHT:1px solid #000000; padding-left:8pt">&#9746;&#8194;&#8201;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">(a)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">The reason described in reasonable detail in Part III of this Form could not be eliminated without unreasonable effort or expense;</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">(b)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">The subject annual report, semi-annual report, transition report on Form <FONT STYLE="white-space:nowrap">10-K,</FONT> Form <FONT STYLE="white-space:nowrap">20-F,</FONT> Form <FONT STYLE="white-space:nowrap">11-K,</FONT> Form <FONT
STYLE="white-space:nowrap">N-CEN</FONT> or Form <FONT STYLE="white-space:nowrap">N-CSR,</FONT> or portion thereof, will be filed on or before the fifteenth calendar day following the prescribed due date; or the subject quarterly report or transition
report on Form <FONT STYLE="white-space:nowrap">10-Q</FONT> or subject distribution report on Form <FONT STYLE="white-space:nowrap">10-D,</FONT> or portion thereof, will be filed on or before the fifth calendar day following the prescribed due date;
and</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">(c)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">The accountant&#146;s statement or other exhibit required by Rule <FONT STYLE="white-space:nowrap">12b-25(c)</FONT> has been attached if applicable.</TD></TR>
</TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART III &#151; NARRATIVE </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">State below in
reasonable detail why Forms <FONT STYLE="white-space:nowrap">10-K,</FONT> <FONT STYLE="white-space:nowrap">20-F,</FONT> <FONT STYLE="white-space:nowrap">11-K,</FONT> <FONT STYLE="white-space:nowrap">10-Q,</FONT>
<FONT STYLE="white-space:nowrap">10-D,</FONT> <FONT STYLE="white-space:nowrap">N-CEN,</FONT> <FONT STYLE="white-space:nowrap">N-CSR,</FONT> or the transition report or portion thereof, could not be filed within the prescribed time period. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Repligen Corporation (the &#147;Company&#148;) has determined that it will not be able to file its Annual Report on Form
<FONT STYLE="white-space:nowrap">10-K</FONT> for the fiscal year ended December&nbsp;31, 2024 (the &#147;2024 Form <FONT STYLE="white-space:nowrap">10-K&#148;)</FONT> within the prescribed time period for such filing without unreasonable effort or
expense. The Company has dedicated significant resources to completing the 2024 Form <FONT STYLE="white-space:nowrap">10-K</FONT> and is working to complete the necessary procedures to file the 2024 Form <FONT STYLE="white-space:nowrap">10-K</FONT>
as soon as practicable. The Company requires additional time to complete the procedures relating to its <FONT STYLE="white-space:nowrap">year-end</FONT> reporting process, including the completion of the audit of the Company&#146;s financial
statements by the Company&#146;s independent auditors for inclusion in the 2024 Form 10-K. The Company expects to file the 2024 Form <FONT STYLE="white-space:nowrap">10-K</FONT> within the extension period provided under Rule <FONT
STYLE="white-space:nowrap">12b-25</FONT> under the Securities Exchange Act of 1934, as amended. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company does not expect the financial results in the
2024 Form <FONT STYLE="white-space:nowrap">10-K</FONT> to differ from the financial results for the quarter and full year ended December&nbsp;31, 2024 set forth in the Company&#146;s press release dated February&nbsp;20, 2025, which is filed as an
exhibit to the Company&#146;s Form <FONT STYLE="white-space:nowrap">8-K</FONT> furnished with the Commission on February&nbsp;20, 2025 (the &#147;2024 Earnings Release&#148;). </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.5pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.50pt solid #000000">&nbsp;</P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART IV &#151; OTHER INFORMATION </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top">(1)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#8195;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9">Name and telephone number of person to contact in regard to this notification</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">Jason K. Garland</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#8195;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">&#8195;&#8195;&#8195;(781)&#8195;&#8195;&#8195;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#8195;</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT STYLE="white-space:nowrap">250-0111</FONT></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>(Name)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>(Area&nbsp;Code)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>(Telephone Number)</B></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="10"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">(2)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9">Have all other periodic reports required under Section&nbsp;13 or 15(d) of the Securities Exchange Act of 1934 or Section&nbsp;30 of the Investment Company Act of 1940 during the preceding 12 months or for such
shorter period that the registrant was required to file such report(s) been filed? If answer is no, identify report(s). &#8195;&#9746;&#8194;Yes&#8195;&#9744;&#8194;No</TD></TR>
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<TD HEIGHT="8" COLSPAN="10"></TD></TR>
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<TD VALIGN="top">(3)</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9">Is it anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or
portion thereof? &#8195;&#9746;&#8194;Yes&#8195;&#9744;&#8194;No</TD></TR>
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<TD HEIGHT="8" COLSPAN="10"></TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9">If so, attach an explanation of the anticipated change, both narratively and quantitatively, and, if appropriate, state the reasons why a reasonable estimate of the results cannot be made.</TD></TR>
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<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="10"></TD></TR>
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<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="9">The Company&#146;s financial results for the quarter and full year ended December&nbsp;31, 2024, compared to the financial results for the corresponding periods in the prior fiscal year are set forth in the 2024
Earnings Release.</TD></TR>
</TABLE> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman"><B><I>Forward-Looking Statements </I></B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:4%; font-size:10pt; font-family:Times New Roman">This Notification of Late Filing contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995
and other federal securities laws. Any statements contained herein which do not describe historical facts, including, among others, statements regarding the expected timing of the filing of the 2024 Form <FONT STYLE="white-space:nowrap">10-K</FONT>
and that the financial results included in the 2024 Form <FONT STYLE="white-space:nowrap">10-K</FONT> are not expected to be different from those disclosed in the 2024 Earnings Release, are based on management&#146;s current expectations and beliefs
and are forward-looking statements which involve risks and uncertainties that could cause actual results to differ materially from those discussed in such forward-looking statements. Such risks and uncertainties include, among others, that the
Company has underestimated the efforts and timing for filing the 2024 Form <FONT STYLE="white-space:nowrap">10-K,</FONT> risks and uncertainties around the effectiveness of the Company&#146;s disclosure controls and procedures and the effectiveness
of the Company&#146;s internal control over financial reporting, the risk that the financial results reported in the 2024 Form <FONT STYLE="white-space:nowrap">10-K</FONT> will differ from those reported in the 2024 Earnings Release, as well as
those risks and uncertainties identified in the Company&#146;s filings with the U.S. Securities and Exchange Commission (the &#147;Commission&#148;), including the Company&#146;s Form <FONT STYLE="white-space:nowrap">10-K</FONT> for the year ended
December 31, 2024 and in any subsequent filings with the Commission, including its Current Reports <FONT STYLE="white-space:nowrap">on&nbsp;Form&nbsp;8-K,</FONT> its&nbsp;Quarterly Reports
<FONT STYLE="white-space:nowrap">on&nbsp;Form&nbsp;10-Q</FONT> and its upcoming 2024 Form <FONT STYLE="white-space:nowrap">10-K,</FONT> which are available at the Commission&#146;s website at www.sec.gov. Any such risks and uncertainties could
materially and adversely affect the Company&#146;s results of operations, its profitability and its cash flows, which would, in turn, have a significant and adverse impact on the Company&#146;s stock price. The Company cautions you not to place
undue reliance on any forward-looking statements, which speak only as of the date they are made. The Company disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or
circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements. </P>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><U>Repligen Corporation </U></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">(Name of Registrant as Specified in Charter) </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">has
caused this notification to be signed on its behalf by the undersigned hereunto duly authorized. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top">Date: March&nbsp;3, 2025</TD>
<TD VALIGN="bottom">&nbsp;</TD>
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<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<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/ Jason K. Garland</P></TD></TR>
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<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">Jason K. Garland</TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
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<TD VALIGN="top"></TD>
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<TD VALIGN="top">Chief Financial Officer</TD></TR>
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