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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:14pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:14pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; 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 8-K
</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:10pt; font-family:Times New Roman" ALIGN="center"><B>CURRENT REPORT </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PURSUANT
TO SECTION&nbsp;13 OR 15(d) OF THE </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES EXCHANGE ACT OF 1934 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Date of Report (Date of earliest event reported): September&nbsp;10, 2013 </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:22pt; font-family:Times New Roman" ALIGN="center"><B>REPLIGEN CORPORATION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Exact name of registrant as specified in its charter) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"><B>Delaware</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>0-14656</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>04-2729386</B></TD></TR>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(State or other jurisdiction</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>of incorporation)</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>(Commission File Number)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(IRS Employer</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Identification No.)</B></P></TD></TR>
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<TD VALIGN="top" ALIGN="center"><B>41 Seyon Street, Bldg. 1, Suite 100, Waltham, MA</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>02453</B></TD></TR>
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<TD VALIGN="top" ALIGN="center"><B>(Address of principal executive offices)</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B>(Zip Code)</B></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Registrant&#146;s telephone number, including area code (781)&nbsp;250-0111 </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Former name or former address, if changed since last report.) </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:10pt; font-family:Times New Roman">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): </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD ALIGN="left" VALIGN="top">Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD ALIGN="left" VALIGN="top">Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD ALIGN="left" VALIGN="top">Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD>
<TD ALIGN="left" VALIGN="top">Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) </TD></TR></TABLE>

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<TD WIDTH="9%" VALIGN="top" ALIGN="left"><B>Item&nbsp;5.02.</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers. </B></TD></TR></TABLE>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(e) On September&nbsp;10, 2013, Repligen Corporation (&#147;<U>Repligen</U>&#148; or &#147;<U>Company</U>&#148;) entered into a Separation
Agreement (the &#147;<U>Separation Agreement</U>&#148;) with Jonathan Lieber in connection with the previously disclosed termination of Mr.&nbsp;Lieber&#146;s employment with the Company effective as of the close of business on August&nbsp;23, 2013
(the &#147;<U>Termination Date</U>&#148;). Under the Separation Agreement, the Company agreed to provide for a period of six months (i)&nbsp;continuation of Mr.&nbsp;Lieber&#146;s base salary in effect on the Termination Date and (ii)&nbsp;if
elected by Mr.&nbsp;Lieber, health insurance plan benefits with the cost of the regular premium for such benefits to be shared in the same relative proportion by the Company and Mr.&nbsp;Lieber as in effect on the Termination Date. In addition, the
Company agreed to accelerate the vesting of a portion of Mr.&nbsp;Lieber&#146;s stock option equal to 22,000 shares that would have vested on September 20, 2013. The Separation Agreement is subject to non-revocation of a general release by
Mr.&nbsp;Lieber. The description of the Separation Agreement does not purport to be complete and is qualified in its entirety by reference to Exhibit 10.1 to this Current Report, which is incorporated by reference herein. </P>
<P STYLE="font-size:18pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="9%" VALIGN="top" ALIGN="left"><B>Item&nbsp;9.01.</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Financial Statements and Exhibits. </B></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" NOWRAP>10.1</TD>
<TD VALIGN="bottom"><FONT STYLE="font-size:8pt">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top">Separation Agreement, dated September 10, 2013, by and between the Company and Jonathan Lieber</TD></TR>
</TABLE>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">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. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top"></TD>
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<TD VALIGN="top" COLSPAN="3"><B>REPLIGEN CORPORATION</B></TD></TR>
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<TD VALIGN="top">Date: September&nbsp;13, 2013</TD>
<TD VALIGN="bottom"><FONT STYLE="font-size:8pt">&nbsp;</FONT></TD>
<TD VALIGN="top"></TD>
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<TD VALIGN="top" ALIGN="right">By:</TD>
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<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Walter C. Herlihy</TD></TR>
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<TD VALIGN="bottom"><FONT STYLE="font-size:8pt">&nbsp;</FONT></TD>
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<TD VALIGN="top"></TD>
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<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Walter C. Herlihy</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">President and Chief Executive
Officer</P></TD></TR>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>EXHIBIT INDEX </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="bottom" NOWRAP> <P STYLE="border-bottom:1.00pt solid #000000; width:39.10pt; font-size:8pt; font-family:Times New Roman"><B>Exhibit&nbsp;No.</B></P></TD>
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<TD VALIGN="bottom" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman"><B>Exhibit</B></P></TD></TR>


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<TD VALIGN="top" NOWRAP>10.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Separation Agreement, dated September 10, 2013, by and between the Company and Jonathan Lieber</TD></TR>
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{"company-data": {"conformed-name": "REPLIGEN CORP", "cik": "0000730272", "assigned-sic": "2836", "irs-number": "042729386", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-14656", "film-number": "131096630"}, "business-address": {"street1": "41 SEYON STREET", "street2": "BUILDING 1, SUITE 100", "city": "WALTHAM", "state": "MA", "zip": "02453", "phone": "7814499560"}, "mail-address": {"street1": "41 SEYON STREET", "street2": "BUILDING 1, SUITE 100", "city": "WALTHAM", "state": "MA", "zip": "02453"}}
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): September 10, 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.
(e) On September 10, 2013, Repligen Corporation ("
Repligen
" or "
Company
") entered into a Separation
Agreement (the "
Separation Agreement
") with Jonathan Lieber in connection with the previously disclosed termination of Mr. Lieber's employment with the Company effective as of the close of business on August 23, 2013
(the "
Termination Date
"). Under the Separation Agreement, the Company agreed to provide for a period of six months (i) continuation of Mr. Lieber's base salary in effect on the Termination Date and (ii) if
elected by Mr. Lieber, health insurance plan benefits with the cost of the regular premium for such benefits to be shared in the same relative proportion by the Company and Mr. Lieber as in effect on the Termination Date. In addition, the
Company agreed to accelerate the vesting of a portion of Mr. Lieber's stock option equal to 22,000 shares that would have vested on September 20, 2013. The Separation Agreement is subject to non-revocation of a general release by
Mr. Lieber. The description of the Separation Agreement does not purport to be complete and is qualified in its entirety by reference to Exhibit 10.1 to this Current Report, which is incorporated by reference herein.
Item 9.01.
Financial Statements and Exhibits.
10.1
Separation Agreement, dated September 10, 2013, by and between the Company and Jonathan Lieber
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: September 13, 2013
By:
/s/ Walter C. Herlihy
Walter C. Herlihy
President and Chief Executive
Officer
EXHIBIT INDEX
Exhibit No.
Exhibit
10.1
Separation Agreement, dated September 10, 2013, by and between the Company and Jonathan Lieber