    <SEC-DOCUMENT>0001571049-17-008599-index.html : 20171127
    <SEC-HEADER>0001571049-17-008599.hdr.sgml : 20171127
    <ACCEPTANCE-DATETIME>20171127092304
    ACCESSION NUMBER:		0001571049-17-008599
    CONFORMED SUBMISSION TYPE:	S-1/A
    PUBLIC DOCUMENT COUNT:		6
    FILED AS OF DATE:		20171127
    DATE AS OF CHANGE:		20171127

    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:		S-1/A
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-221467
    		FILM NUMBER:		171221963

    	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>S-1/A
    <SEQUENCE>1
    <FILENAME>t1702958-s1a.htm
    <DESCRIPTION>AMENDMENT NO. 1 TO FORM S-1
    <TEXT>
    Document 1 - file: t1702958-s1a.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>2
    <FILENAME>lg_clearsign.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 2 - file: lg_clearsign.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>3
    <FILENAME>t1702894_duplex-reduce.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: t1702894_duplex-reduce.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>4
    <FILENAME>t1702894_duplex-increase.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 4 - file: t1702894_duplex-increase.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>5
    <FILENAME>t1702894_map-ozone.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 5 - file: t1702894_map-ozone.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>6
    <FILENAME>t1702894_map-ozoneproj.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 6 - file: t1702894_map-ozoneproj.jpg

    </DOCUMENT>
    </SEC-DOCUMENT>