<SEC-DOCUMENT>0001193125-12-350008.txt : 20120810
<SEC-HEADER>0001193125-12-350008.hdr.sgml : 20120810
<ACCEPTANCE-DATETIME>20120810161606
ACCESSION NUMBER:		0001193125-12-350008
CONFORMED SUBMISSION TYPE:	S-8
PUBLIC DOCUMENT COUNT:		3
FILED AS OF DATE:		20120810
DATE AS OF CHANGE:		20120810
EFFECTIVENESS DATE:		20120810

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CERUS CORP
		CENTRAL INDEX KEY:			0001020214
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				680262011
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-8
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-183232
		FILM NUMBER:		121024780

	BUSINESS ADDRESS:	
		STREET 1:		2550 STANWELL DRIVE
		CITY:			CONCORD
		STATE:			CA
		ZIP:			94520
		BUSINESS PHONE:		9252886000

	MAIL ADDRESS:	
		STREET 1:		2550 STANWELL DRIVE
		STREET 2:		STE 300
		CITY:			CONCORD
		STATE:			CA
		ZIP:			94520

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CERUS TECHNOLOGIES INC
		DATE OF NAME CHANGE:	19960731
</SEC-HEADER>
<DOCUMENT>
<TYPE>S-8
<SEQUENCE>1
<FILENAME>d394865ds8.htm
<DESCRIPTION>FORM S-8
<TEXT>
<HTML><HEAD>
<TITLE>Form S-8</TITLE>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>As filed with the Securities and Exchange Commission on August&nbsp;10, 2012
</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Registration No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </B></FONT></P>
<P STYLE="font-size:4px;margin-top:0px;margin-bottom:0px">&nbsp;</P> <P STYLE="line-height:0px;margin-top:0px;margin-bottom:0px;border-bottom:0.5pt solid #000000">&nbsp;</P>
<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>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:6px;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:6px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="5"><B>FORM S-8 </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="5"><B>REGISTRATION STATEMENT </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="3"><B><I>UNDER </I></B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="3"><B><I>THE SECURITIES ACT OF 1933 </I></B></FONT></P>
<P STYLE="font-size:6px;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:6px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="6"><B>CERUS 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:6px;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="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Delaware</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>68-0262011</B></FONT></TD></TR>
<TR>
<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(State of Incorporation)</B></FONT></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>(I.R.S. 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>
</TABLE> <P STYLE="font-size:6px;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="2"><B>2550 Stanwell Drive </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>Concord, California 94520 </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>(925) 288-6000 </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(Address of principal executive offices) </B></FONT></P> <P STYLE="font-size:6px;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:6px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>2008 Equity
Incentive Plan </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>1996 Employee Stock Purchase Plan </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(Full titles of the plans) </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>William M. Greenman </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>President and Chief Executive Officer
</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>CERUS CORPORATION </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>2550 Stanwell Drive </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Concord, California 94520 </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>(925) 288-6000 </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="1"><B>(Name, address, including zip code, and telephone number, including area code, of agent for service) </B></FONT></P> <P STYLE="font-size:6px;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="2"><B><I>Copies to:
</I></B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Chadwick L. Mills </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>Cooley LLP </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>3175 Hanover Street </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Palo Alto, CA 94304-1130 </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>(650) 843-5000 </B></FONT></P> <P STYLE="font-size:6px;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:6px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">Indicate by
check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of &#147;large accelerated filer,&#148; &#147;accelerated filer&#148; and &#147;smaller
reporting company&#148; in Rule&nbsp;12b-2 of the Exchange Act. </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD WIDTH="60%"></TD>
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<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Large&nbsp;accelerated&nbsp;filer</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Accelerated&nbsp;filer</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></FONT></TD></TR>
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<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
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<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Non-accelerated filer</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;(Do not check if a smaller reporting company)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Smaller&nbsp;reporting&nbsp;company</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></FONT></TD></TR>
</TABLE> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>CALCULATION OF REGISTRATION FEE </B></FONT></P>
<P STYLE="font-size:4px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD WIDTH="44%"></TD>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1px solid #000000">&nbsp;</P></TD></TR>
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<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Title of Securities to be Registered</B></FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Amount to be<BR>Registered (2)</B></FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Proposed Maximum<BR>Offering Price Per<BR>Share (3)</B></FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Proposed Maximum<BR>Aggregate Offering<BR>Price (3)</B></FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Amount of<BR>Registration Fee</B></FONT></TD></TR>
<TR>
<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT STYLE="font-family:Times New Roman" SIZE="2">Common Stock, par value $0.001 per share, including related rights to purchase Series&nbsp;C
Junior Participating Preferred Stock(1)</FONT></P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">3,500,000</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">$3.24</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">$11,340,000.00</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">$1,299.57</FONT></TD></TR>
<TR STYLE="font-size:1px">
<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1px solid #000000">&nbsp;</P></TD></TR>
<TR STYLE="font-size:1px">
<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1px solid #000000">&nbsp;</P></TD></TR>
</TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(1)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Each share of the Registrant&#146;s Common Stock registered hereunder, if issued prior to the termination of the Registrant&#146;s rights agreement, dated as of
November&nbsp;3, 1999, as amended, between the Registrant and the rights agent named therein, includes Series C junior participating preferred stock purchase rights (the &#147;Rights&#148;). Prior to the occurrence of certain events, the Rights will
not be exercisable or evidenced separately from the Registrant&#146;s Common Stock, and have no value except as reflected in the market price of the shares of the Registrant&#146;s Common Stock to which they are attached. </FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(2)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Pursuant to Rule 416 under the Securities Act of 1933, as amended (the &#147;Act&#148;), this Registration Statement shall cover any additional shares of Common Stock
that become issuable under the Registrant&#146;s 2008 Equity Incentive Plan (the &#147;EIP&#148;) and 1996 Employee Stock Purchase Plan (the &#147;ESPP&#148; and, together with the EIP, the &#147;Plans&#148;) set forth herein by reason of any stock
dividend, stock split, recapitalization or any other similar transaction without receipt of consideration which results in an increase in the number of shares of the Registrant&#146;s outstanding Common Stock. </FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(3)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Estimated solely for the purpose of calculating the amount of the registration fee. The offering price per share and aggregate offering price are based the average of
the high and low prices of the Registrant&#146;s Common Stock as reported on The NASDAQ Global Market on August&nbsp;7, 2012, in accordance with Rule 457(c) under the Act. </FONT></TD></TR></TABLE>
<P STYLE="font-size:8px;margin-top:0px;margin-bottom:0px">&nbsp;</P> <P STYLE="line-height:0px;margin-top:0px;margin-bottom:0px;border-bottom:0.5pt solid #000000">&nbsp;</P>
<P STYLE="line-height:3px;margin-top:0px;margin-bottom:2px;border-bottom:0.5pt solid #000000">&nbsp;</P>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>EXPLANATORY NOTE </B></FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">This Registration Statement on Form S-8 is being filed for the purpose of registering an additional 3,500,000 shares of the
Registrant&#146;s Common Stock, $0.001 par value, comprised of (i)&nbsp;3,000,000 shares of the Registrant&#146;s Common Stock to be issued pursuant to the EIP, and (ii)&nbsp;500,000 shares of the Registrant&#146;s Common Stock to be issued pursuant
to the ESPP. The shares of the Registrant&#146;s Common Stock previously reserved for issuance under the EIP were registered on the Registrant&#146;s Registration Statements on Form S-8 (File Nos. 333-177751 and 333-152680) filed with the Securities
and Exchange Commission on November&nbsp;4, 2011 and July&nbsp;31, 2008, respectively. The shares of the Registrant&#146;s Common Stock previously reserved for issuance under the ESPP were registered on the Registrant&#146;s Registration Statements
on Form S-8 (File Nos. 333-127541, 333-125043, 333-109170 and 333-27097), filed with the Securities and Exchange Commission on August&nbsp;15, 2005,&nbsp;May&nbsp;19, 2005,&nbsp;September&nbsp;26, 2003 and May&nbsp;14, 1997, respectively.
</FONT></P>

<p Style='page-break-before:always'>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>PART II </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;3. Incorporation of
Documents by Reference. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">The following documents have been filed by the Registrant with the Securities and Exchange
Commission (the &#147;Commission&#148;) and are incorporated herein by reference: </FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
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<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the Registrant&#146;s Annual Report on Form 10-K for the fiscal year ended December&nbsp;31, 2011 filed with the Commission on March&nbsp;5, 2012 (the
&#147;2011 Form 10-K&#148;); </FONT></P></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the information specifically incorporated by reference into the 2011 Form 10-K from the Registrant&#146;s definitive proxy statement on Schedule 14A,
filed with the Commission on April&nbsp;26, 2012; </FONT></P></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the Registrant&#146;s Quarterly Report on Form 10-Q for the quarterly period ended March&nbsp;31, 2012 filed with the Commission on May&nbsp;7, 2012;
</FONT></P></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the Registrant&#146;s Quarterly Report on Form 10-Q for the quarterly period ended June&nbsp;30, 2012 filed with the Commission on August&nbsp;8, 2012;
</FONT></P></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the Registrant&#146;s Current Reports on Form 8-K, filed with the Commission on June&nbsp;8, 2012 and July&nbsp;9, 2012; </FONT></P></TD></TR></TABLE>
<P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the description of the Registrant&#146;s Common Stock contained in the Registrant&#146;s registration statement on Form 8-A filed with the Commission
on January&nbsp;8, 1997, including any amendments or reports filed for the purpose of updating such description; and </FONT></P></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the description of the Registrant&#146;s preferred share purchase rights in the Registrant&#146;s registration statement on Form 8-A filed with the
Commission on October&nbsp;30, 2009, including any amendments or reports filed for the purpose of updating such description. </FONT></P></TD></TR></TABLE> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
STYLE="font-family:Times New Roman" SIZE="2">All documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended (the &#147;Exchange Act&#148;), other than current
reports furnished under Item&nbsp;2.02 or Item&nbsp;7.01 of Form 8-K and exhibits furnished on such form that relate to such items, prior to the filing of a post-effective amendment to this Registration Statement which indicates that all of the
shares of Common Stock offered have been sold or which deregisters all of such shares then remaining unsold, shall be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of the filing of such
documents. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">For purposes of this Registration Statement, any statement contained in a document incorporated or deemed to be
incorporated by reference herein shall be deemed to be modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or
supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement. </FONT></P> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;4. Description of Securities</B>. </FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">Not applicable. </FONT></P>
<P STYLE="margin-top:18px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;5. Interests of Named Experts and Counsel. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT
STYLE="font-family:Times New Roman" SIZE="2">Not applicable. </FONT></P>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;6. Indemnification of Directors and Officers. </B></FONT></P>
<P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">As permitted by Delaware law, the Registrant&#146;s amended and restated certificate of incorporation provides that no director will be
personally liable to the Registrant or the Registrant&#146;s stockholders for monetary damages for breach of fiduciary duty as a director, except for liability: </FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">for any breach of the duty of loyalty to the Registrant or the Registrant&#146;s stockholders; </FONT></P></TD></TR></TABLE>
<P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">for acts or omissions not in good faith or that involve intentional misconduct or a knowing violation of law; </FONT></P></TD></TR></TABLE>
<P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">for unlawful payment of dividends or unlawful stock repurchases or redemptions under Section&nbsp;174 of the Delaware General Corporation Law; and
</FONT></P></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">for any transaction from which the director derived an improper personal benefit. </FONT></P></TD></TR></TABLE>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">The Company&#146;s amended and restated certificate of incorporation further provides that the Registrant must indemnify the
Registrant&#146;s directors to the fullest extent permitted by Delaware law. In addition, the Registrant&#146;s amended and restated bylaws provide that: </FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the Registrant is required to indemnify the Registrant&#146;s directors and executive officers to the fullest extent not prohibited by Delaware law,
subject to limited exceptions; </FONT></P></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the Registrant may indemnify the Registrant&#146;s other employees and agents as set forth in the Delaware General Corporation Law;
</FONT></P></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the Registrant is required to advance expenses to the Registrant&#146;s directors and executive officers as incurred in connection with legal
proceedings against them for which they may be indemnified, against an undertaking by the indemnified party to repay such advances if it is ultimately determined that the indemnified party is not entitled to indemnification; and
</FONT></P></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">the rights conferred in the amended and restated bylaws are not exclusive. </FONT></P></TD></TR></TABLE>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">The Company has entered into indemnification agreements with each of the Registrant&#146;s directors and executive officers that require
the Registrant to indemnify these people against expenses, witness fees, damages, judgments, fines and settlement amounts incurred by the director or officer in any action or proceeding, whether actual, pending or threatened, subject to certain
limitations, to which any of these people may be made a party by reason of the fact that he or she is or was a director or an executive officer of the Registrant or is or was serving or at any time serves at the request of the Registrant as a
director, officer, employee or other agent of another corporation, partnership, joint venture, trust, employee benefit plan or other enterprise. </FONT></P> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;7. Exemption from Registration Claimed. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">Not Applicable.
</FONT></P> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;8. Exhibits. </B></FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE" ALIGN="center">


<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="7%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR>
<TD VALIGN="bottom" NOWRAP> <P STYLE="border-bottom:1px solid #000000;width:28pt"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Exhibit<BR>Number</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD></TR>


<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">3.1(1)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Amended and Restated Certificate of Incorporation of Cerus Corporation</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">3.2(2)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Certificate of Amendment to the Amended and Restated Certificate of Incorporation of Cerus Corporation</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">3.3(3)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Amended and Restated Bylaws of Cerus Corporation</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">4.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Reference is made to Exhibits 3.1, 3.2 and 3.3</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">4.2(4)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Specimen Stock Certificate</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">4.3(5)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Rights Agreement, dated as of November 3, 1999, as amended as of August 6, 2001, between Cerus Corporation and Wells Fargo Bank, N.A. (formerly known as Norwest Bank Minnesota,
N.A.).</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">4.4(6)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Amendment to Rights Agreement, dated as of October 28, 2009, between Cerus Corporation and Wells Fargo Bank, N.A. (which includes the form of Rights Certificate as Exhibit B
thereto).</FONT></TD></TR>
</TABLE>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE" ALIGN="center">


<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="94%"></TD></TR>


<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;5.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Opinion of Cooley LLP</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">10.1(7)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">2008 Equity Incentive Plan, as amended, effective June 6, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">10.2(7)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Employee Stock Purchase Plan, as amended, effective June 6, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">23.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Consent of Independent Registered Public Accounting Firm</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">23.2</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Consent of Cooley LLP is contained in Exhibit 5.1 to this Registration Statement</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">24.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Power of Attorney is contained on the signature pages</FONT></TD></TR>
</TABLE> <P STYLE="line-height:8px;margin-top:0px;margin-bottom:2px;border-bottom:0.5pt solid #000000;width:10%">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(1)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Current Report on Form 8-K (No. 333-72185), filed with the SEC on November&nbsp;12, 1999. </FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(2)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Quarterly Report on Form 10-Q (File No. 000-21937), for the quarter ended June&nbsp;30, 2010.
</FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(3)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Current Report on Form 8-K (File No. 000-21937), filed with the SEC on June&nbsp;19, 2008. </FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(4)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Registration Statement on Form S-1 (File No.&nbsp;333-11341), and amendments thereto. </FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(5)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Quarterly Report on Form 10-Q (File No. 000-21937), for the quarter ended June&nbsp;30, 2009.
</FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(6)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Current Report on Form 8-K (File No. 000-21937), filed with the SEC on October&nbsp;30, 2009.
</FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(7)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Quarterly Report on Form 10-Q (File No. 000-21937), for the quarter ended June&nbsp;30, 2012.
</FONT></TD></TR></TABLE> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;9. Undertakings. </B></FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">1.</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">The undersigned Registrant hereby undertakes: </FONT></TD></TR></TABLE> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
STYLE="font-family:Times New Roman" SIZE="2">(a) To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement: </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT
STYLE="font-family:Times New Roman" SIZE="2">(i) To include any prospectus required by section 10(a)(3) of the Securities Act of 1933; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT
STYLE="font-family:Times New Roman" SIZE="2">(ii) To reflect in the prospectus any facts or events arising after the effective date of the Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the
aggregate, represent a fundamental change in the information set forth in the Registration Statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not
exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in
volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the &#147;Calculation of Registration Fee&#148; table in the effective Registration Statement. </FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT STYLE="font-family:Times New Roman" SIZE="2">(iii) To include any material information with respect to the plan of distribution not previously disclosed in the Registration Statement
or any material change to such information in the Registration Statement; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><I>Provided</I>, <I>however</I>, that paragraphs
(a)(i) and (a)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Registrant pursuant to section 13 or section 15(d)
of the Securities Exchange Act of 1934 that are incorporated by reference herein. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">(b) That, for the purpose of determining
any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be
the initial <I>bona fide</I> offering thereof. </FONT></P>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">(c) To remove from registration by means of a post-effective amendment any of the securities
being registered which remain unsold at the termination of the offering. </FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">2.</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the Registrant&#146;s
annual report pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan&#146;s annual report pursuant to section 15(d) of the Securities Exchange Act of 1934)
that is incorporated by reference in the Registration Statement shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial <I>bona
fide</I> offering thereof. </FONT></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">3.</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Registrant
pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is,
therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful
defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by
controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.
</FONT></TD></TR></TABLE>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>SIGNATURES </B></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 Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and
has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Concord, State of California, on this 10th day of August, 2012. </FONT></P>
<P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE">


<TR>
<TD WIDTH="6%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR>
<TD VALIGN="top" COLSPAN="3"><FONT STYLE="font-family:Times New Roman" SIZE="2">Cerus Corporation</FONT></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">By:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<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/ William M. Greenman</FONT></P></TD></TR>
<TR>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">William M. Greenman</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px"><FONT STYLE="font-family:Times New Roman" SIZE="2">President and Chief Executive Officer</FONT></P></TD></TR>
</TABLE></DIV>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>POWER OF ATTORNEY </B></FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">Each person whose signature appears below constitutes and appoints William M. Greenman and Kevin D. Green, each acting alone, as his true
and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for him and in his name, place and stead, in any and all capacities, to sign any or all amendments (including post-effective amendments) to this Registration
Statement on Form S-8, and to file the same, with all exhibits thereto, and all documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorney-in-fact and agent, full power and authority to do and perform
each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent, or his
substitute or substitutes, may lawfully do or cause to be done by virtue hereof. </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 Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated. </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE">


<TR>
<TD WIDTH="37%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="44%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="15%"></TD></TR>
<TR>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1px solid #000000;width:33pt" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Signature</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1px solid #000000;width:15pt" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Title</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1px solid #000000;width:16pt" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Date</B></FONT></P></TD></TR>


<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ William M. Greenman</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px; margin-left:1.00em; text-indent:-1.00em"><FONT STYLE="font-family:Times New Roman" SIZE="2">William M. Greenman</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">President, Chief Executive Officer and Director (Principal Executive Officer)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">August 10, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Kevin D. Green</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px; margin-left:1.00em; text-indent:-1.00em"><FONT STYLE="font-family:Times New Roman" SIZE="2">Kevin D. Green</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Vice President, Finance and Chief Accounting Officer (Principal Financial and Accounting Officer)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">August 10, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ B.J. Cassin</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px; margin-left:1.00em; text-indent:-1.00em"><FONT STYLE="font-family:Times New Roman" SIZE="2">B.J. Cassin</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Chairman of the Board of Directors</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">August 10, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Timothy B. Anderson</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px; margin-left:1.00em; text-indent:-1.00em"><FONT STYLE="font-family:Times New Roman" SIZE="2">Timothy B. Anderson</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">August 10, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Laurence M. Corash, M.D.</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px; margin-left:1.00em; text-indent:-1.00em"><FONT STYLE="font-family:Times New Roman" SIZE="2">Laurence M. Corash, M.D.</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">August 10, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Bruce C. Cozadd</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px; margin-left:1.00em; text-indent:-1.00em"><FONT STYLE="font-family:Times New Roman" SIZE="2">Bruce C. Cozadd</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">August 10, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Gail Schulze</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px; margin-left:1.00em; text-indent:-1.00em"><FONT STYLE="font-family:Times New Roman" SIZE="2">Gail Schulze</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">August 10, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Daniel N. Swisher, Jr.</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px; margin-left:1.00em; text-indent:-1.00em"><FONT STYLE="font-family:Times New Roman" SIZE="2">Daniel N. Swisher, Jr.</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">August 10, 2012</FONT></TD></TR>
</TABLE>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>EXHIBITS </B></FONT></P>
<P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE" ALIGN="center">


<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="7%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR>
<TD VALIGN="bottom" NOWRAP> <P STYLE="border-bottom:1px solid #000000;width:28pt"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Exhibit<BR>Number</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD></TR>


<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;3.1(1)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Amended and Restated Certificate of Incorporation of Cerus Corporation</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;3.2(2)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Certificate of Amendment to the Amended and Restated Certificate of Incorporation of Cerus Corporation</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;3.3(3)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Amended and Restated Bylaws of Cerus Corporation</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Reference is made to Exhibits 3.1, 3.2 and 3.3</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.2(4)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Specimen Stock Certificate</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.3(5)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Rights Agreement, dated as of November 3, 1999, as amended as of August 6, 2001, between Cerus Corporation and Wells Fargo Bank, N.A. (formerly known as Norwest Bank Minnesota,
N.A.)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.4(6)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Amendment to Rights Agreement, dated as of October 28, 2009, between Cerus Corporation and Wells Fargo Bank, N.A. (which includes the form of Rights Certificate as Exhibit B
thereto)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;5.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Opinion of Cooley LLP</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">10.1(7)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">2008 Equity Incentive Plan, as amended, effective June 6, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">10.2(7)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Employee Stock Purchase Plan, as amended, effective June 6, 2012</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">23.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Consent of Independent Registered Public Accounting Firm</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">23.2</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Consent of Cooley LLP is contained in Exhibit 5.1 to this Registration Statement</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">24.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Power of Attorney is contained on the signature pages</FONT></TD></TR>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(1)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Current Report on Form 8-K (No. 333-72185), filed with the SEC on November&nbsp;12, 1999. </FONT></TD></TR></TABLE>
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<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(2)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Quarterly Report on Form 10-Q (File No. 000-21937) for the quarter ended June&nbsp;30, 2010.
</FONT></TD></TR></TABLE>
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<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(3)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Current Report on Form 8-K (File No. 000-21937), filed with the SEC on June&nbsp;19, 2008. </FONT></TD></TR></TABLE>
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<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(4)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Registration Statement on Form S-1 (File No.&nbsp;333-11341) and amendments thereto. </FONT></TD></TR></TABLE>
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<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(5)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Quarterly Report on Form 10-Q (File No. 000-21937), for the quarter ended June&nbsp;30, 2009.
</FONT></TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(6)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Current Report on Form 8-K (File No. 000-21937), filed with the SEC on October&nbsp;30, 2009.
</FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(7)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Incorporated by reference to the Registrant&#146;s Quarterly Report on Form 10-Q (File No. 000-21937), for the quarter ended June&nbsp;30, 2012.
</FONT></TD></TR></TABLE>
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</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>2
<FILENAME>d394865dex51.htm
<DESCRIPTION>OPINION OF COOLEY LLP
<TEXT>
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<TITLE>Opinion of Cooley LLP</TITLE>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Exhibit 5.1 </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2">[Letterhead of Cooley LLP] </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">August&nbsp;10, 2012 </FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Cerus Corporation </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">2550 Stanwell Drive
</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Concord, CA 94520 </FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Ladies and
Gentlemen: </FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">You have requested our opinion with respect to certain matters in connection with the filing by Cerus Corporation (the
&#147;<B><I>Company</I></B>&#148;) of a Registration Statement on Form&nbsp;S-8 (the &#147;<B><I>Registration Statement</I></B>&#148;) with the U.S. Securities and Exchange Commission covering the offering of up to 3,500,000 shares of the
Company&#146;s Common Stock, $0.001 par value per share, comprised of (i)&nbsp;500,000 shares of the Company&#146;s Common Stock (the &#147;<B><I>ESPP Shares</I></B>&#148;) to be issued pursuant to the Company&#146;s 1996 Employee Stock Purchase
Plan (the &#147;<B><I>ESPP</I></B>&#148;), and (ii)&nbsp;3,000,000 shares of the Company&#146;s Common Stock (the &#147;<B><I>EIP Shares</I></B>&#148; and, together with the ESPP Shares, the &#147;<B><I>Shares</I></B>&#148;) to be issued pursuant to
the Company&#146;s 2008 Equity Incentive Plan (the &#147;<B><I>EIP</I></B>&#148; and, together with the ESPP, the &#147;<B><I>Plans</I></B>&#148;), and the preferred stock purchase rights (the &#147;<B><I>Rights</I></B>&#148;) associated with the
Shares to be issued pursuant to that certain Rights Agreement, dated as of November&nbsp;3, 1999, as amended (the &#147;<B><I>Rights Agreement</I></B>&#148;), between the Company and Wells Fargo Bank, N.A., as successor to Wells Fargo Bank
Minnesota, N.A. (formerly Norwest Bank Minnesota, N.A.) as rights agent (the &#147;<B><I>Rights Agent</I></B>&#148;). </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">In connection with this
opinion, we have examined the Plans, the Registration Statement and related prospectuses, the Company&#146;s Certificate of Incorporation and Bylaws, as amended and restated, the Rights Agreement and such other documents, records, certificates,
memoranda and other instruments as we deem necessary as a basis for this opinion. We have assumed the genuineness and authenticity of all documents submitted to us as originals, the conformity to originals of all documents submitted to us as copies
thereof and the due execution and delivery of all documents where due execution and delivery are a prerequisite to the effectiveness thereof. We have also assumed that the Rights Agreement has been duly authorized, executed and delivered by the
Rights Agent and that the members of the Board of Directors of the Company (the &#147;<B><I>Board</I></B>&#148;) have acted in a manner consistent with their fiduciary duties as required under applicable law in adopting the Rights Agreement.
</FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Our opinion is limited to the matters stated herein and no opinion is implied or may be inferred beyond the matters expressly stated. Our
opinion herein is expressed solely with respect to the federal laws of the United States and the General Corporation Law of the State of Delaware. Our opinion is based on these laws as in effect on the date hereof, and we disclaim any obligation to
advise you of facts, circumstances, events or developments which hereafter may be brought to our attention and which may alter, affect or modify the opinion expressed herein. We express no opinion as to whether the laws of any particular
jurisdiction other than those identified above are applicable to the subject matter hereof. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">On the basis of the foregoing, and in reliance
thereon, we are of the opinion that the Shares and the associated Rights, when sold and issued in accordance with the Plans, and the Registration Statement and related prospectuses, will be validly issued, and the Shares fully paid and nonassessable
(except as to shares issued pursuant to certain deferred payment arrangements, which will be fully paid and nonassessable when such deferred payments are made in full). </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2">This opinion assumes, with your consent, that the Rights Agreement has been duly authorized, executed and delivered by the Rights Agent, and that the Board has acted in accordance with its fiduciary
duties in adopting the Rights Agreement. This opinion does not address the determination a court of competent jurisdiction may make </FONT></P>

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<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">
regarding whether the Board may be required to redeem or terminate, or take other action with respect to, the Rights in the future based on the facts and circumstances then existing. Moreover,
this opinion addresses corporate procedures in connection with the issuance of the Rights associated with the Shares, and not any particular provision of the Rights or the Rights Agreement. It should be understood that it is not settled whether the
invalidity of any particular provision of a rights agreement or purchase rights issued thereunder would invalidate such rights in their entirety. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2">We consent to the filing of this opinion as an exhibit to the Registration Statement. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Very truly
yours, </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Cooley LLP </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">By:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<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/ Chadwick L. Mills</FONT></P></TD></TR>
<TR>
<TD VALIGN="top"><FONT SIZE="">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Chadwick L. Mills</FONT></TD></TR>
<TR>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
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</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>3
<FILENAME>d394865dex231.htm
<DESCRIPTION>CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
<TEXT>
<HTML><HEAD>
<TITLE>Consent of Independent Registered Public Accounting Firm</TITLE>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Exhibit 23.1 </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">We consent to the incorporation
by reference in the Registration Statement (Form S-8) pertaining to the 2008 Equity Incentive Plan and the 1996 Employee Stock Purchase Plan of Cerus Corporation of our reports dated March&nbsp;5, 2012, with respect to the consolidated financial
statements of Cerus Corporation and the effectiveness of internal control over financial reporting of Cerus Corporation included in its Annual Report (Form 10-K) for the year ended December&nbsp;31, 2011, filed with the Securities and Exchange
Commission. </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P> <P STYLE="margin-top:0px;margin-bottom:0px; margin-left:54%; text-indent:-2%"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Ernst&nbsp;&amp; Young
LLP </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; margin-left:2%; text-indent:-2%"><FONT STYLE="font-family:Times New Roman" SIZE="2">Redwood City, California </FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px; margin-left:2%; text-indent:-2%"><FONT STYLE="font-family:Times New Roman" SIZE="2">August&nbsp;8, 2012 </FONT></P>
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