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<P STYLE="line-height:3px;margin-top:0px;margin-bottom:2px;border-bottom:0.5pt solid #000000">&nbsp;</P> <P STYLE="margin-top:4px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="5"><B>UNITED STATES </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="5"><B>SECURITIES AND EXCHANGE COMMISSION </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="3"><B>Washington, D.C. 20549 </B></FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center>
<P STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="5"><B>FORM 8-K
</B></FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center> <P STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="3"><B>CURRENT REPORT </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="3"><B>PURSUANT TO SECTION&nbsp;13 OR 15(d) </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="3"><B>OF THE SECURITIES EXCHANGE ACT OF
1934 </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="3"><B>Date of Report (Date of earliest event reported): August&nbsp;22, 2013 </B></FONT></P>
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<P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="6"><B>REPLIGEN CORPORATION </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>(Exact name of registrant as specified in its charter) </B></FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center>
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<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Delaware</B></FONT></TD>
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<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>0-14656</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>04-2729386</B></FONT></TD></TR>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(State or other jurisdiction</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="1"><B>of incorporation)</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(Commission</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="1"><B>File Number)</B></FONT></P></TD>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(IRS Employer</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="1"><B>Identification No.)</B></FONT></P></TD></TR>
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<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>41 Seyon Street, Bldg. 1, Suite 100, Waltham, MA</B></FONT></TD>
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<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>02453</B></FONT></TD></TR>
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<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(Address of principal executive offices)</B></FONT></TD>
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<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(Zip Code)</B></FONT></TD></TR>
</TABLE> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Registrant&#146;s telephone number, including area code (781)&nbsp;250-0111 </B></FONT></P>
<P STYLE="margin-top:24px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(Former name or former address, if changed since last report.) </B></FONT></P>
<P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center> <P STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2">Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2.
below): </FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) </FONT></TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) </FONT></TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) </FONT></TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) </FONT></TD></TR></TABLE>
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<TD WIDTH="10%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;5.02.</B></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.
</B></FONT></TD></TR></TABLE> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:8%"><FONT STYLE="font-family:Times New Roman" SIZE="2">On August&nbsp;22, 2013, Repligen Corporation (the &#147;Company&#148;) and Jonathan I. Lieber agreed to
terminate Mr.&nbsp;Lieber&#146;s employment with the Company without Cause (as such term is defined in Mr.&nbsp;Lieber&#146;s Employment Offer Letter, dated September&nbsp;20, 2012), effective as of the close of business on August&nbsp;23, 2013.
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">SIGNATURES </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
STYLE="font-family:Times New Roman" SIZE="2">Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. </FONT></P>
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<TD VALIGN="top" COLSPAN="3"><FONT STYLE="font-family:Times New Roman" SIZE="2">REPLIGEN CORPORATION</FONT></TD></TR>
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<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Date: August&nbsp;28, 2013</FONT></TD>
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<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">By:</FONT></TD>
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<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Walter C. Herlihy</FONT></P></TD></TR>
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<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Walter C. Herlihy</FONT></TD></TR>
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<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">President and Chief Executive Officer</FONT></TD></TR>
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Form 8-K
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 8-K
CURRENT REPORT
PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF
1934
Date of Report (Date of earliest event reported): August 22, 2013
REPLIGEN CORPORATION
(Exact name of registrant as specified in its charter)
Delaware
0-14656
04-2729386
(State or other jurisdiction
of incorporation)
(Commission
File Number)
(IRS Employer
Identification No.)
41 Seyon Street, Bldg. 1, Suite 100, Waltham, MA
02453
(Address of principal executive offices)
(Zip Code)
Registrant's telephone number, including area code (781) 250-0111
(Former name or former address, if changed since last report.)
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2.
below):
¨
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
¨
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
¨
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
¨
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Item 5.02.
Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.
On August 22, 2013, Repligen Corporation (the "Company") and Jonathan I. Lieber agreed to
terminate Mr. Lieber's employment with the Company without Cause (as such term is defined in Mr. Lieber's Employment Offer Letter, dated September 20, 2012), effective as of the close of business on August 23, 2013.
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
REPLIGEN CORPORATION
Date: August 28, 2013
By:
/s/ Walter C. Herlihy
Walter C. Herlihy
President and Chief Executive Officer