<SEC-DOCUMENT>0001068800-12-000057.txt : 20120507
<SEC-HEADER>0001068800-12-000057.hdr.sgml : 20120507
<ACCEPTANCE-DATETIME>20120507110741
ACCESSION NUMBER:		0001068800-12-000057
CONFORMED SUBMISSION TYPE:	SC 13D/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20120507
DATE AS OF CHANGE:		20120507

SUBJECT COMPANY:	

	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:		SC 13D/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-38071
		FILM NUMBER:		12816476

	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

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CHEZ RONALD L
		CENTRAL INDEX KEY:			0000942801

	FILING VALUES:
		FORM TYPE:		SC 13D/A

	MAIL ADDRESS:	
		STREET 1:		219 E. LAKE SHORE DRIVE
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60611
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13D/A
<SEQUENCE>1
<FILENAME>sched13da.htm
<TEXT>
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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">SECURITIES AND EXCHANGE COMMISSION</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 10pt">Washington, D.C. 20549</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">Under the Securities Exchange Act of 1934</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">(Amendment No. 11)*</font></div>

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<div style="TEXT-ALIGN: center; TEXT-INDENT: 0pt; DISPLAY: block"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt"><font style="DISPLAY: inline">REPLIGEN CORP</font></font></div>

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<font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 10pt">(Name of Issuer)</font></div>

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<font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt"><font style="DISPLAY: inline">Common Stock, Par Value $0.01 Per Share</font></font></div>

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<font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 10pt">(Title of Class of Securities)</font></div>

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<div style="TEXT-ALIGN: center; TEXT-INDENT: 0pt; DISPLAY: block"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt"><font style="DISPLAY: inline">759916 10 9</font></font></div>

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<font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 10pt">(CUSIP Number)</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">Barry L. Fischer</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">Thompson Coburn LLP</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">55 East Monroe Street</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">Suite 3700</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">Chicago, IL 60603</font></div>

<div style="TEXT-ALIGN: center; TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt"><font style="DISPLAY: inline">(312) 346-7500</font></font></div>

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<div style="TEXT-ALIGN: center; TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 10pt">(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)</font></div>

<div style="TEXT-ALIGN: center; TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 10pt">&#160;</font></div>

<div style="TEXT-ALIGN: center; TEXT-INDENT: 0pt; DISPLAY: block"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt"><font style="DISPLAY: inline">May 4th,&#160;2012</font></font></div>

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<font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 10pt">(Date of Event which Requires Filing of this Statement)</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(e), (f) or (g), check the following box <a name="Check1"><!--EFPlaceholder--></a><font style="DISPLAY: inline;" face="Wingdings">o</font>.</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">Note:&#160;&#160;Schedules filed in paper format shall include a signed original and five copies of the Schedule, including all exhibits.&#160;&#160;See Rule 13d-7(b) for other parties to whom copies are being sent.</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">*The remainder of this cover page shall be filled out for a reporting person&#8217;s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">The information required on the remainder of this cover page shall not be deemed to be &#8220;filed&#8221; for the purpose of Section 18 of the Securities Exchange Act of 1934 (&#8220;Act&#8221;) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).</font></div>

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<div>&#160;</div>

<div><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">&#160;</font></div>

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<table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">
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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">1</font></div>
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<td valign="top" width="70%" style="BORDER-BOTTOM: black 4px double; BORDER-TOP: black 1.5pt double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">NAMES OF REPORTING PERSON</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block">&#160;</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block">&#160;</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">Individual Retirement Accounts for the benefit of Ronald L. Chez and Ronald L. Chez Individually</font></div>
</td>
<td valign="top" width="7%" style="BORDER-BOTTOM: black 4px double; BORDER-TOP: black 1.5pt double"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160; </font></td>
</tr><tr>
<td valign="top" width="3%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">2</font></div>
</td>
<td valign="top" width="70%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block">&#160;</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block">&#160;</div>
</td>
<td valign="top" width="7%" style="BORDER-BOTTOM: black 4px double; TEXT-ALIGN: right">
<div style="TEXT-ALIGN: right; TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">(a) <font style="DISPLAY: inline; FONT-FAMILY: wingdings">o</font></font></div>

<div style="TEXT-ALIGN: right; TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">(b) <font style="DISPLAY: inline; FONT-FAMILY: wingdings">o</font></font></div>
</td>
</tr><tr>
<td valign="top" width="3%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">3</font></div>
</td>
<td valign="top" width="70%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">SEC USE ONLY</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block">&#160;</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block">&#160;</div>
</td>
<td valign="top" width="7%" style="BORDER-BOTTOM: black 4px double"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160; </font></td>
</tr><tr>
<td valign="top" width="3%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">4</font></div>
</td>
<td valign="top" width="70%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">SOURCE OF FUNDS (See Instructions)</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">PF</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify">&#160;</div>
</td>
<td valign="top" width="7%" style="BORDER-BOTTOM: black 4px double"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160; </font></td>
</tr><tr>
<td valign="top" width="3%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">5</font></div>
</td>
<td valign="top" width="70%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#8194;</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#8194;&#8194;&#8194;&#8194;</font></div>
</td>
<td valign="top" width="7%" style="BORDER-BOTTOM: black 4px double; TEXT-ALIGN: right"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160; <font style="DISPLAY: inline; FONT-FAMILY: wingdings">o</font></font></td>
</tr><tr>
<td valign="top" width="3%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">6</font></div>
</td>
<td valign="top" width="70%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">CITIZENSHIP OR PLACE OF ORGANIZATION</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">United States of America</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify">&#160;</div>
</td>
<td valign="top" width="7%" style="BORDER-BOTTOM: black 4px double"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160; </font></td>
</tr></table>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block">
<div>
<table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">
<tr>
<td colspan="2" valign="bottom" width="13%">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">NUMBER OF</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">SHARES</font></font></div>
</td>
<td valign="top" width="4%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">7</font></font></div>
</td>
<td valign="top" width="63%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">SOLE VOTING POWER</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">&#160;<font size="3">2,845,931</font></font></font></div>
</td>
</tr><tr>
<td colspan="2" valign="top" width="13%">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">BENEFICIALLY</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">OWNED BY</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">EACH</font></div>
</td>
<td valign="top" width="4%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">8</font></div>
</td>
<td valign="top" width="63%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">SHARED VOTING POWER</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">0</font></div>
</td>
</tr><tr>
<td colspan="2" valign="top" width="13%" style="TEXT-ALIGN: center; PADDING-BOTTOM: 4px"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160; <font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">REPORTING</font> </font>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">PERSON</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">WITH</font></font></div>
</td>
<td valign="top" width="4%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">9</font></div>
</td>
<td valign="top" width="63%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">SOLE DISPOSITIVE POWER</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">0</font></div>
</td>
</tr><tr>
<td colspan="2" valign="top" width="13%" style="BORDER-BOTTOM: black 4px double"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160; </font></td>
<td valign="top" width="4%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">10</font></div>
</td>
<td valign="top" width="63%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">SHARED DISPOSITIVE POWER</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">&#160;<font size="3">2,845,931</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
</td>
</tr><tr>
<td valign="top" width="4%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">11</font></div>
</td>
<td colspan="3" valign="top" width="75%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">&#160;<font size="3">2,855,931</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
</td>
</tr></table>

<table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman">
<tr>
<td valign="top" width="5%" style="BORDER-BOTTOM: black 4px double"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">12</font></td>
<td valign="top" width="86%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES</font></font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160;</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160;</font></div>
</td>
<td colspan="2" valign="top" width="9%" style="BORDER-BOTTOM: black 4px double; TEXT-ALIGN: right">
<div style="TEXT-ALIGN: right; TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160; <font style="DISPLAY: inline; FONT-FAMILY: wingdings">o</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160;</font></div>
</td>
</tr><tr>
<td valign="top" width="5%" style="BORDER-BOTTOM: black 4px double"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">13</font></td>
<td colspan="3" valign="top" width="75%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-WEIGHT: bold">9.2%</font><font style="DISPLAY: inline; FONT-SIZE: 70%; VERTICAL-ALIGN: text-top">(1)</font></font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160;</font></div>
</td>
</tr><tr>
<td valign="top" width="5%" style="BORDER-BOTTOM: black 4px double"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold">14</font></td>
<td colspan="3" valign="top" width="75%" style="BORDER-BOTTOM: black 4px double">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">TYPE OF REPORTING PERSON (See Instructions)</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">IN</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160;</font></div>
</td>
</tr></table>
</div>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block">&#160;</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">________________________________</font></div>

<br>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-SIZE: 70%; VERTICAL-ALIGN: text-top"><font id="TAB2" style="LETTER-SPACING: 9pt">&#160;&#160;&#160;</font>&#160;(1)</font>&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;<font style="DISPLAY: inline; FONT-SIZE: 10pt">Based upon <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font style="DISPLAY: inline; FONT-SIZE: 10pt">30,841,165 shares of the Issuer&#8217;s common stock issued and outstanding as of April 9, 2012, as reported on the Issuer&#8217;s Proxy Statement dated April 20, 2012.</font></font><br>
</font></font></div>
</div>
</div>

<div id="PGBRK" style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt">
<div id="FTR">
<div id="GLFTR" style="WIDTH: 100%" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 8pt">&#160; </font></div>
</div>

<div id="PN" style="PAGE-BREAK-AFTER: always; WIDTH: 100%">
<div style="TEXT-ALIGN: center; WIDTH: 100%"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 8pt">&#160; </font></div>

<div style="TEXT-ALIGN: center; WIDTH: 100%">
<hr style="COLOR: black" noshade size="2">
</div>
</div>

<div id="HDR">
<div id="GLHDR" style="WIDTH: 100%" align="right"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 8pt">&#160; </font></div>

<br>
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Pursuant to Rule 13d-2 of Regulation 13D-G of the General Rules and Regulations under the Securities Exchange Act of 1934, as amended, the undersigned, Ronald L. Chez (the "Reporting Person") hereby amends his statement on Schedule 13D dated January 30, 2007, as amended by Amendment No. 1 to Schedule 13D dated July 13, 2007; Amendment No. 2 to Schedule 13D dated October 20, 2008; Amendment No. 3 to Schedule 13D dated June 20, 2011; Amendment No. 4 to Schedule 13D dated July 13, 2011; and Amendment No. 5 to Schedule 13D dated August 15, 2011; Amendment No. 6 to Schedule 13D dated January 25, 2012; Amendment No. 7 to Schedule 13D dated March 5, 2012; Amendment No. 8 to Schedule 13D dated March 21, 2012; Amendment No. 9 to Schedule 13D dated March 21, 2012; and Amendment No. 10 to Schedule 13D dated as of April 30, 2012&#160;&#160;(collectively, the &#8220;Schedule 13D&#8221;).&#160;&#160;This Statement constitutes Amendment No. 11 to the Schedule 13D.&#160;&#160;Unless otherwise indicated herein, there are no material changes to the information set forth in the Schedule 13D.</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt"><font style="DISPLAY: inline; FONT-WEIGHT: bold">Item 4.</font>&#160;&#160; <font style="DISPLAY: inline; FONT-WEIGHT: bold">Purpose of Transaction</font> is hereby amended by adding thereto the following<font style="DISPLAY: inline; FONT-WEIGHT: bold">:</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt"><font id="TAB1" style="MARGIN-LEFT: 36pt"></font>On May 4, 2012, the Reporting Person and the Issuer entered into an agreement regarding the Reporting Person&#8217;s shareholder proposal (the &#8220;Agreement&#8221;).&#160;&#160;Please see Item 6 of this Schedule 13D for a description of the Agreement.</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt"><font style="DISPLAY: inline; FONT-WEIGHT: bold">Item 5.</font>&#160;&#160; <font style="DISPLAY: inline; FONT-WEIGHT: bold">Interest in Securities of the Issuer </font>is hereby amended and restated in its entirety as follows<font style="DISPLAY: inline; FONT-WEIGHT: bold">:</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div>
<table cellpadding="0" cellspacing="0" id="list" width="100%" style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman">
<tr valign="top">
<td align="right" style="WIDTH: 27pt">
<div><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">(a)&#160;&#160;</font></div>
</td>
<td>
<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">The aggregate number of shares of the Stock owned beneficially by the Reporting Person is 2,845,931 (the "Shares") constituting approximately 9.2% of the outstanding shares of the Stock.&#160;&#160;&#160;The percentages in this Item&#160;&#160;5(a) are based upon 30,841,165 shares of the Issuer&#8217;s common stock issued and outstanding as of April 9, 2012, as reported on the Issuer&#8217;s Proxy Statement dated April 20, 2012.</font></div>
</td>
</tr></table>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div>
<table cellpadding="0" cellspacing="0" id="list" width="100%" style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman">
<tr valign="top">
<td align="right" style="WIDTH: 27pt">
<div><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">(b)&#160;&#160;</font></div>
</td>
<td>
<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">The Reporting Person has the sole power (and no shared power) to vote or dispose of or direct the disposition of Shares owned by such Reporting Person.</font></div>
</td>
</tr></table>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div>
<table cellpadding="0" cellspacing="0" id="list" width="100%" style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman">
<tr valign="top">
<td align="right" style="WIDTH: 27pt">
<div><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">(c)&#160;&#160;</font></div>
</td>
<td>
<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">Since the filing of the prior amendment to this Schedule 13D on April 30, 2012 (the date of the event that necessitated the filing of the immediately prior amendment to the Schedule 13D), the Reporting Person purchased shares of Stock (through open market transactions) as follows:</font></div>
</td>
</tr></table>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div align="center">
<table cellpadding="0" cellspacing="0" width="50%" style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman">
<tr>
<td valign="top" width="14%" style="BORDER-BOTTOM: black 2px solid; BORDER-LEFT: black 2px solid; BORDER-TOP: black 0.5pt solid; BORDER-RIGHT: black 2px solid">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt; FONT-WEIGHT: bold">DATE</font></div>
</td>
<td valign="top" width="16%" style="BORDER-BOTTOM: black 2px solid; BORDER-TOP: black 0.5pt solid; BORDER-RIGHT: black 2px solid">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt; FONT-WEIGHT: bold">QUANTITY</font></div>
</td>
<td valign="top" width="21%" style="BORDER-BOTTOM: black 2px solid; BORDER-TOP: black 0.5pt solid; BORDER-RIGHT: black 2px solid">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt; FONT-WEIGHT: bold">PRICE PER SHARE</font></div>
</td>
</tr><tr>
<td valign="top" width="14%" style="BORDER-BOTTOM: black 2px solid; BORDER-LEFT: black 2px solid; BORDER-RIGHT: black 2px solid">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt">&#160;4/30/2012</font></div>
</td>
<td valign="top" width="16%" style="BORDER-BOTTOM: black 2px solid; BORDER-RIGHT: black 2px solid">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt">26,000</font></div>
</td>
<td valign="top" width="21%" style="BORDER-BOTTOM: black 2px solid; BORDER-RIGHT: black 2px solid">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt">4.42</font></div>
</td>
</tr><tr>
<td valign="top" width="14%" style="BORDER-BOTTOM: black 2px solid; BORDER-LEFT: black 2px solid; BORDER-RIGHT: black 2px solid">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt">&#160;5/1/2012</font></div>
</td>
<td valign="top" width="16%" style="BORDER-BOTTOM: black 2px solid; BORDER-RIGHT: black 2px solid">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt">4,300</font></div>
</td>
<td valign="top" width="21%" style="BORDER-BOTTOM: black 2px solid; BORDER-RIGHT: black 2px solid">
<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-FAMILY: times new roman, serif; FONT-SIZE: 12pt">4.47</font></div>
</td>
</tr></table>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div>
<table cellpadding="0" cellspacing="0" id="list" width="100%" style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman">
<tr valign="top">
<td align="right" style="WIDTH: 27pt">
<div><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">(d)&#160;&#160;</font></div>
</td>
<td>
<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">Not applicable.</font></div>
</td>
</tr></table>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div>
<table cellpadding="0" cellspacing="0" id="list" width="100%" style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman">
<tr valign="top">
<td align="right" style="WIDTH: 27pt">
<div><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">(e)&#160;&#160;</font></div>
</td>
<td>
<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">Not applicable.</font></div>
</td>
</tr></table>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div id="PGBRK" style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt">
<div id="FTR">
<div id="GLFTR" style="WIDTH: 100%" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 8pt">&#160; </font></div>
</div>

<div id="PN" style="PAGE-BREAK-AFTER: always; WIDTH: 100%">
<div style="TEXT-ALIGN: center; WIDTH: 100%"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 8pt">&#160; </font></div>

<div style="TEXT-ALIGN: center; WIDTH: 100%">
<hr style="COLOR: black" noshade size="2">
</div>
</div>

<div id="HDR">
<div id="GLHDR" style="WIDTH: 100%" align="right"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 8pt">&#160; </font></div>
</div>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt"><font style="DISPLAY: inline; FONT-WEIGHT: bold">Item 6.</font>&#160;&#160; <font style="DISPLAY: inline; FONT-WEIGHT: bold">Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer </font>is hereby amended by adding thereto the following<font style="DISPLAY: inline; FONT-WEIGHT: bold">:</font></font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 27pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">On May 4, 2012, as described above, the Issuer and the Reporting Person entered into the Agreement, pursuant to which, among other things:</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block"><br>
</div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 27pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">&#8226;&#160;&#160;&#160;The Reporting Person submitted the Amended and Restated Proposal to lower the threshold necessary for calling a special meeting of stockholders to the holders of 30% of the voting shares of the Issuer;</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 27pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">&#8226;&#160;&#160;&#160;Subject to and conditioned upon the Issuer&#8217;s filing of the Additional Soliciting Materials with the SEC and the distribution thereof to its stockholders, the Reporting Person agreed to vote, or cause to be voted, by no later than May 17, 2012, all of the voting shares of the Issuer held or controlled by the Reporting Person in accordance with the recommendation of the Board with respect to each of the proposals to be acted upon at the Annual Meeting (and further agreed not to revoke, amend or otherwise alter such vote);</font></div>

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<div style="TEXT-INDENT: 36pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 12pt">A copy of the May 4, 2012 Agreement between the Issuer and the Reporting Person described in Items 4 and 6 above is attached hereto as <font style="DISPLAY: inline; TEXT-DECORATION: underline">Exhibit A</font> to this Amendment No. 11 to&#160;&#160;Schedule 13D.</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 36pt"></font>THIS AGREEMENT (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Agreement</font>&#8221;) is made and entered into as of May 4, 2012, by and between Ronald L. Chez (together with any affiliate thereof, the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Stockholder</font>&#8221;) and Repligen Corporation, a Delaware corporation (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Company</font>&#8221;).</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 36pt"></font>WHEREAS, the Stockholder submitted a proposal to the Company under Rule 14a-8 of the Securities Exchange Act of 1934, as amended (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Exchange Act</font>&#8221;), regarding the adoption of an amendment to the Amended and Restated By-Laws of the Company which would lower the threshold necessary for calling a special meeting of stockholders from a majority to the holders of 20% of the outstanding voting shares of the Company (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Proposal</font>&#8221;);</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 36pt"></font>WHEREAS, pursuant to Rule 14a-8 of the Exchange Act, the Company included the Proposal in the Company&#8217;s definitive 2012 proxy statement and form of proxy (together, the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">2012 Proxy Materials</font>&#8221;) filed with the Securities and Exchange Commission (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">SEC</font>&#8221;) on April 20, 2012 and first sent or given to the Company&#8217;s stockholders on or about April 23, 2012; and</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 36pt"></font>WHEREAS, the Stockholder and the Company desire to enter into this Agreement pursuant to which, among other things, (i) the Stockholder agrees to amend and restate the Proposal in the form attached hereto as <font style="DISPLAY: inline; TEXT-DECORATION: underline">Exhibit A</font> (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Amended and Restated Proposal</font>&#8221;), (ii)&#160;the Company&#8217;s Board of Directors (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Board</font>&#8221;) agrees to recommend that the Company&#8217;s stockholders vote &#8220;<font style="DISPLAY: inline; FONT-WEIGHT: bold">FOR</font>&#8221; the Amended and Restated Proposal and (iii) the Stockholder agrees to vote all of the voting shares of the Company held or controlled by the Stockholder (collectively, the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Shares</font>&#8221;) in accordance with the recommendation of the Board with respect to each of the proposals to be acted upon at the Company&#8217;s 2012 Annual Meeting of Stockholders (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">2012</font> <font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Annual Meeting</font>&#8221;).</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 36pt"></font>NOW, THEREFORE, in consideration of these premises and the covenants contained herein, the parties hereto, each intending to be legally bound, hereby agree as follows:</font></div>

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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">The Stockholder hereby agrees to amend and restate, and hereby submits, the Proposal in the form attached hereto as <font style="DISPLAY: inline; TEXT-DECORATION: underline">Exhibit A</font>.</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">The Company hereby agrees to prepare, file with the SEC and distribute to its stockholders, definitive additional soliciting materials relating to the 2012 Proxy Materials to reflect the Amended and Restated Proposal and the Board&#8217;s recommendation that the Company&#8217;s stockholders vote &#8220;<font style="DISPLAY: inline; FONT-WEIGHT: bold">FOR</font>&#8221; the Amended and Restated Proposal in substantially the form attached hereto as <font style="DISPLAY: inline; TEXT-DECORATION: underline">Exhibit B</font> (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Additional Soliciting Materials</font>&#8221;).</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">Subject to and conditioned upon the Company&#8217;s filing of the Additional Soliciting Materials with the SEC and the distribution thereof to its stockholders, the Stockholder hereby agrees to vote, or cause to be voted, by no later than May 17, 2012, all of the Shares in accordance with the recommendation of the Board with respect to each of the proposals to be acted upon at the 2012 Annual Meeting&#160;&#160;(and further agrees not to revoke, amend or otherwise alter such vote).</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">The Company hereby confirms to the Stockholder that (i) achievement of the Company&#8217;s previously disclosed cash bonus compensation objective for the fiscal year ending December 31, 2012 related to &#8220;the performance of the Company&#8217;s stock against the Russell 2000 Index&#8221; requires that the Company&#8217;s stock outperform the Russell 2000 Index in order for such compensation objective to be achieved and (ii) the Compensation Committee will assign meaningful weight to such compensation objective when determining executive officers&#8217; cash bonus compensation for the fiscal year ending December 31, 2012.</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">The Company hereby confirms to the Stockholder that Board will amend the Company&#8217;s Stock Ownership and Retention Policy (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Policy</font>&#8221;) to provide that if the annual cash retainer paid to non-employee members of the Board is reduced to zero or some de minimis amount, such reduction shall not decrease the previously effective minimum share ownership requirements under the Policy.</font></div>
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<div><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">c.&#160;&#160;</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">The Company hereby confirms to the Stockholder that Board will amend the Policy to reduce the period for a director to comply with the Policy from five years to four years, subject to and conditioned upon the performance by the Stockholder of its obligations under <font style="DISPLAY: inline; TEXT-DECORATION: underline">Section 2</font> of this Agreement.</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font style="DISPLAY: inline; TEXT-DECORATION: underline">Irrevocable Proxy</font>.&#160;&#160;Subject to the last sentence of this Section, by execution of this Agreement, the Stockholder does hereby appoint the Company with full power of substitution and resubstitution, as the Stockholder's true and lawful attorney and irrevocable proxy, to the fullest extent of the Stockholder&#8217;s rights with respect to the Shares, to vote, each of such Shares solely in accordance with Section 2 of this Agreement.&#160;&#160;The Stockholder intends this proxy to be irrevocable and coupled with an interest hereunder until the conclusion of the 2012 Annual Meeting and hereby revokes any proxy previously granted by the Stockholder with respect to the Shares.&#160;&#160;Notwithstanding anything contained herein to the contrary, this irrevocable proxy shall automatically terminate upon the conclusion of the 2012 Annual Meeting.&#160;&#160;The Stockholder hereby revokes any proxies previously granted, and represents that none of such previously-granted proxies are irrevocable.</font></div>
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<div><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">5.&#160;&#160;</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font style="DISPLAY: inline; TEXT-DECORATION: underline">Notices</font>.&#160;&#160;All notices, consents, requests, instructions, approvals and other communications provided for herein and all legal process in regard hereto shall be in writing and shall be deemed validly given, made or served, if (a) given by facsimile, when such facsimile is transmitted to the facsimile number set forth below and the appropriate confirmation is received, (b) given by email, including .PDFs, upon confirmation by the receiving party, or (c) if given by any other means, when actually received during normal business hours at the address specified in this subsection:</font></div>
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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 72pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">If to the Company:</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Repligen Corporation</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;41 Seyon Street, Building #1, Suite 100</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Waltham, Massachusetts 02453</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Attention: Walter C. Herlihy, President and Chief Executive Officer</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Fax No. (781) 250-0115</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Email: wherlihy@repligen.com</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;With a copy (which shall not constitute notice) to:</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Goodwin Procter LLP</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;53 State Street</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Boston, Massachusetts 02109</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Attention: Joseph L. Johnson III and Arthur R. McGivern</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Fax No. (617) 523-1231</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Email: amcgivern@goodwinprocter.com</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 107.75pt"></font>&#160;jjohnson@goodwinprocter.com</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 72pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">If to the Stockholder:</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Ronald L. Chez</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>1524 N. Astor Street</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Chicago, Illinois 60610</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Email: rlchez@rcn.com</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 72pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">With a copy (which shall not constitute notice) to:</font></div>

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<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Thompson Coburn LLP</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>55 East Monroe Street, 37<font style="DISPLAY: inline; FONT-SIZE: 70%; VERTICAL-ALIGN: text-top">th</font> Floor</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Chicago, Illinois 60603</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Attention: Barry Fischer</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Fax No. (312) 580-2201</font></div>

<div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font id="TAB1" style="MARGIN-LEFT: 79.4pt"></font>Email: bfischer@thompsoncoburn.com</font></div>

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<div><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt">6.&#160;&#160;</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font style="DISPLAY: inline; TEXT-DECORATION: underline">Publicity</font>.&#160;&#160;Except for the press release attached hereto as <font style="DISPLAY: inline; TEXT-DECORATION: underline">Exhibit D</font>, with respect to the Additional Soliciting Materials and the solicitation of votes or proxies in connection with the 2012 Annual Meeting, or the Stockholder&#8217;s Schedule 13D in substantially the form attached hereto as <font style="DISPLAY: inline; TEXT-DECORATION: underline">Exhibit C</font>, neither the Company nor the Stockholder shall, or shall permit any of its affiliates or representatives to, issue or cause the publication of any press release or other public announcement with respect to, or otherwise make any public statement concerning, the transactions contemplated by this Agreement, including all discussions between the parties and their advisors related thereto, without the consent of the other party, except as may be required by applicable law or the applicable rules of any stock exchange or the Nasdaq Stock Market LLC.</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font style="DISPLAY: inline; TEXT-DECORATION: underline">Specific Performance</font>.&#160;&#160;The Company and the Stockholder acknowledge and agree that irreparable injury to the other party would occur in the event any of the provisions of the Agreement were not performed in accordance with their specific terms or were otherwise breached and that such injury would not be adequately compensable in damages.&#160;&#160;Therefore, without prejudice to the rights and remedies otherwise available to it, the parties agree that each party hereto (the &#8220;<font style="FONT-STYLE: italic; DISPLAY: inline; FONT-WEIGHT: bold">Moving Party</font>&#8221;) shall be entitled to specific enforcement of, and injunctive relief to prevent any violation of, the terms hereof and the other parties hereto will not take action, directly or indirectly, in opposition to the Moving Party seeking such relief on the grounds that any other remedy or relief is available at law or in equity.</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font style="DISPLAY: inline; TEXT-DECORATION: underline">Entire Agreement</font>.&#160;&#160;The Agreement, including the preamble and recitals above, contains the entire understanding of the parties with respect to the subject matter hereof and may be amended only by an agreement in writing executed by the parties hereto.</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font style="DISPLAY: inline; TEXT-DECORATION: underline">Construction</font>.&#160;&#160;The parties acknowledge that each party and its counsel has reviewed this Agreement and that any rule of construction to the effect that any ambiguities are to be resolved against the drafting party shall not be employed in the interpretation or construction of this Agreement.</font></div>
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<div style="TEXT-INDENT: 0pt; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-FAMILY: Times New Roman, serif; FONT-SIZE: 11pt"><font style="DISPLAY: inline; TEXT-DECORATION: underline">Severability</font>.&#160;&#160;If at any time subsequent to the date hereof, any provision of the Agreement shall be held by any court of competent jurisdiction to be illegal, void or unenforceable, such provision shall be of no force and effect, but the illegality or unenforceability of such provision shall have no effect upon the legality or enforceability of any other provision of the Agreement.</font></div>
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