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Proc-Type: 2001,MIC-CLEAR
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<SEC-DOCUMENT>0001193125-09-183173.txt : 20100831
<SEC-HEADER>0001193125-09-183173.hdr.sgml : 20100831
<ACCEPTANCE-DATETIME>20090827212913
<PRIVATE-TO-PUBLIC>
ACCESSION NUMBER:		0001193125-09-183173
CONFORMED SUBMISSION TYPE:	CORRESP
PUBLIC DOCUMENT COUNT:		2
FILED AS OF DATE:		20090827

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ARROWHEAD RESEARCH CORP
		CENTRAL INDEX KEY:			0000879407
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMMERCIAL PHYSICAL & BIOLOGICAL RESEARCH [8731]
		IRS NUMBER:				460408024
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	FILING VALUES:
		FORM TYPE:		CORRESP

	BUSINESS ADDRESS:	
		STREET 1:		201 SOUTH LAKE AVENUE
		STREET 2:		SUITE 703
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91101
		BUSINESS PHONE:		626-304-3400

	MAIL ADDRESS:	
		STREET 1:		201 SOUTH LAKE AVENUE
		STREET 2:		SUITE 703
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91101

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERACTIVE GROUP INC
		DATE OF NAME CHANGE:	20020509

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERACTIVE INC
		DATE OF NAME CHANGE:	19940224
</SEC-HEADER>
<DOCUMENT>
<TYPE>CORRESP
<SEQUENCE>1
<FILENAME>filename1.htm
<TEXT>
<HTML><HEAD>
<TITLE>SEC Response Letter</TITLE>
</HEAD>
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<TD VALIGN="top" COLSPAN="3"> <P STYLE="margin-left:1.00em; text-indent:-1.00em">

<IMG SRC="g81028goodwinlogo.jpg" ALT="LOGO"></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1">Goodwin Procter LLP</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1">Counselors at Law</FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1">Three Embarcadero Center,</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1">24th Floor</FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1">San Francisco, CA 94111</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1">T: 415.733.6000</FONT></P> <P
STYLE="margin-top:0px;margin-bottom:1px"><FONT FACE="Times New Roman" SIZE="1">F: 415.677.9041</FONT></P></TD></TR>
</TABLE> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">August&nbsp;27, 2009 </FONT></P> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT FACE="Times New Roman"
SIZE="2"><B><U>VIA EDGAR AND FEDEX </U></B></FONT></P> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Michael Rosenthall </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman"
SIZE="2">United States Securities and Exchange Commission </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Division of Corporation Finance </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT
FACE="Times New Roman" SIZE="2">100 F Street, N.E., Mail Stop 4720 </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Washington, DC 20549 </FONT></P> <P
STYLE="font-size:18px;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%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><B>Re:</B></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B>Arrowhead Research Corporation </B></FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><B>&nbsp;&nbsp;&nbsp;&nbsp;</B></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B>Registration Statement on Form S-1 </B></FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><B>&nbsp;&nbsp;&nbsp;&nbsp;</B></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B>Filed August&nbsp;13, 2009 </B></FONT></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><B>&nbsp;&nbsp;&nbsp;&nbsp;</B></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B>File No.&nbsp;333-161344 </B></FONT></TD></TR></TABLE> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Dear Mr.&nbsp;Rosenthall: </FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">On behalf of our client Arrowhead Research Corporation (the &#147;<U>Company</U>&#148;), this letter responds to the comments of the Staff of the
Securities and Exchange Commission set forth in the letter dated August&nbsp;25, 2009 related to the above-referenced registration statement. We are also filing herewith Amendment No.&nbsp;1 to the registration statement (the
&#147;<U>Amendment</U>&#148;), which is intended to address the comment contained in your letter. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">For reference purposes, the text of the
Staff&#146;s comment, as set forth in the August&nbsp;25, 2009 comment letter, has been reproduced herein in italicized text, followed by the Company&#146;s response. </FONT></P> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT
FACE="Times New Roman" SIZE="2"><I><U>Registration Statement on Form S-1 filed August&nbsp;13, 2009 </U></I></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><I><U>Selling Security Holders, page 14
</U></I></FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><I>1.</I></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><I>We note that there are significant inconsistencies between the number of shares held by each selling stockholder before the offering and the number of shares offered by each
selling stockholder. Please revise your disclosure to clarify the correct number of shares owned by each selling stockholder prior to the offering, and the correct number of shares offered by each selling stockholder. </I></FONT></TD></TR></TABLE>

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

 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Michael Rosenthall </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman"
SIZE="2">August&nbsp;27, 2009 </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Page 2 </FONT></P> <P STYLE="margin-top:24px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><I><U>Response</U></I>:
</FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">We have amended the selling security holder table in the Amendment to clarify that the holdings of the selling stockholders before the
offering include the shares to be offered pursuant to the prospectus. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">* * * * * * * * </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">If you should have any questions concerning the foregoing, please contact me at (415)&nbsp;733-6000. Thank you very much for your assistance. </FONT></P>
<P STYLE="font-size:18px;margin-top:0px;margin-bottom:0px">&nbsp;</P><DIV ALIGN="right">
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<TD VALIGN="top" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">Sincerely,</FONT></TD></TR>
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<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR>
<TD VALIGN="top" COLSPAN="3" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT FACE="Times New Roman" SIZE="2">/s/ Ryan Murr</FONT></TD></TR>
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<TD VALIGN="top" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">Ryan Murr</FONT></TD></TR>
</TABLE></DIV> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Encl. </FONT></P>
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