    <SEC-DOCUMENT>0001144204-18-010843-index.html : 20180226
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    <ACCEPTANCE-DATETIME>20180226153257
    ACCESSION NUMBER:		0001144204-18-010843
    CONFORMED SUBMISSION TYPE:	424B5
    PUBLIC DOCUMENT COUNT:		8
    FILED AS OF DATE:		20180226
    DATE AS OF CHANGE:		20180226

    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:		18640312

    	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
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    <DESCRIPTION>PROSPECTUS SUPPLEMENT
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    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 4 - file: line.gif

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    <FILENAME>tv486668_img-dplxreduce.jpg
    <DESCRIPTION>GRAPHIC
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    Document 5 - file: tv486668_img-dplxreduce.jpg

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

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    <FILENAME>tv486668_map-ozoneproj.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
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