<SEC-DOCUMENT>0001144204-12-022875.txt : 20120522
<SEC-HEADER>0001144204-12-022875.hdr.sgml : 20120522
<ACCEPTANCE-DATETIME>20120420140104
<PRIVATE-TO-PUBLIC>
ACCESSION NUMBER:		0001144204-12-022875
CONFORMED SUBMISSION TYPE:	CORRESP
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20120420

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CLEARSIGN COMBUSTION CORP
		CENTRAL INDEX KEY:			0001434524
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL INSTRUMENTS FOR MEASUREMENT, DISPLAY, AND CONTROL [3823]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			WA

	FILING VALUES:
		FORM TYPE:		CORRESP

	BUSINESS ADDRESS:	
		STREET 1:		12870 INTERURBAN AVENUE SOUTH
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98168
		BUSINESS PHONE:		(206) 673-4848

	MAIL ADDRESS:	
		STREET 1:		12870 INTERURBAN AVENUE SOUTH
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98168
</SEC-HEADER>
<DOCUMENT>
<TYPE>CORRESP
<SEQUENCE>1
<FILENAME>filename1.htm
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<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: left"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>CLEARSIGN COMBUSTION CORPORATION</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>12870 Interurban Avenue South</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>Seattle, Washington 98168</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><B>&nbsp;</B></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">April 20, 2012</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: normal 10pt Times New Roman, Times, Serif; margin: 0pt 0"><U>VIA EDGAR</U></P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Amanda Ravitz</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Assistant Director</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">United States Securities and Exchange Commission</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Division of Corporate Finance/Mail Stop 4561</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">100 F Street, N.E.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Washington, D.C. 20549</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

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<TD STYLE="width: 1in"></TD><TD STYLE="width: 0.5in">Re:</TD><TD>ClearSign Combustion Corporation</TD></TR></TABLE>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 1.5in">Registration Statement on Form S-1</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 1.5in">Filed on November 14, 2011 and amended on December
28, 2011,</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 1.5in">February 7, 2012, March 9, 2012, April 6, 2012 and
April 18, 2012</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 1.5in">File No. 333-177946</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">Dear Ms. Ravitz:</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-indent: 0.5in">ClearSign Combustion Corporation (the &ldquo;Company&rdquo;)
hereby requests that the Securities and Exchange Commission take appropriate action to make the above-captioned registration statement
be ordered effective at 4 p.m., Eastern time, on April 24, 2012 or as soon as practicable thereafter.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-indent: 0.5in">In requesting acceleration, the Company
acknowledges that:</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-indent: 0.5in">(1)&#9;should the Commission or the staff,
acting pursuant to delegated authority, declare the filing effective, it does not foreclose the Commission from taking any action
with respect to the filing;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-indent: 0.5in">(2)&#9;the action of the Commission or the
staff, acting pursuant to delegated authority in declaring the filing effective does not relieve the Company from its full responsibility
for the adequacy and accuracy of the disclosure in the filing; and</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-indent: 0.5in">(3)&#9;the Company may not assert the declaration
of effectiveness as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of
the United States.</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">&nbsp;</P>

<P STYLE="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"></P>

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    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD>
    <TD COLSPAN="2">Very truly yours,&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD>
    </TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; width: 50%">&nbsp;</TD>
    <TD STYLE="width: 3%">&nbsp;</TD>
    <TD STYLE="width: 35%">&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt; width: 12%">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD>
    <TD COLSPAN="2">CLEARSIGN COMBUSTION CORPORATION&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD>
    <TD>By:</TD>
    <TD STYLE="border-bottom: Black 1pt solid">/s/ Richard Rutkowski</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>Richard Rutkowski, Chief Executive Officer&nbsp;</TD>
    <TD STYLE="padding-right: 5.4pt; padding-left: 5.4pt">&nbsp;</TD></TR>
</TABLE>


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