<SEC-DOCUMENT>0001144204-18-010298-index.html : 20180222
<SEC-HEADER>0001144204-18-010298.hdr.sgml : 20180222
<ACCEPTANCE-DATETIME>20180222171926
ACCESSION NUMBER:		0001144204-18-010298
CONFORMED SUBMISSION TYPE:	424B5
PUBLIC DOCUMENT COUNT:		8
FILED AS OF DATE:		20180222
DATE AS OF CHANGE:		20180222

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
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		424B5
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-208784
		FILM NUMBER:		18633585

	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>
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<DESCRIPTION>PRELIMINARY PROSPECTUS SUPPLEMENT
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Document 1 - file: tv486668_424b5.htm

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Document 2 - file: logo_clearsign.jpg

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Document 3 - file: spacer.gif

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<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>4
<FILENAME>tv486668_img-dplxreduce.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 4 - file: tv486668_img-dplxreduce.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>5
<FILENAME>tv486668_img-dplxincrease.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 5 - file: tv486668_img-dplxincrease.jpg

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<FILENAME>tv486668_map-ozone.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 6 - file: tv486668_map-ozone.jpg

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<FILENAME>tv486668_map-ozoneproj.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 7 - file: tv486668_map-ozoneproj.jpg

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<SEQUENCE>8
<FILENAME>line.gif
<DESCRIPTION>GRAPHIC
<TEXT>
Document 8 - file: line.gif

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