<SEC-DOCUMENT>0001144204-19-025694.txt : 20190513
<SEC-HEADER>0001144204-19-025694.hdr.sgml : 20190513
<ACCEPTANCE-DATETIME>20190513184628
ACCESSION NUMBER:		0001144204-19-025694
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190509
FILED AS OF DATE:		20190513
DATE AS OF CHANGE:		20190513

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BELL LON E
		CENTRAL INDEX KEY:			0000941593

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35521
		FILM NUMBER:		19820012

	MAIL ADDRESS:	
		STREET 1:		C/O AMERIGON INC
		STREET 2:		5462 IRWINDALE AVENUE
		CITY:			IRWINDALE
		STATE:			CA
		ZIP:			91706

ISSUER:		

	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

	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>4
<SEQUENCE>1
<FILENAME>tv521420_4.xml
<DESCRIPTION>OWNERSHIP DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-05-09</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001434524</issuerCik>
        <issuerName>CLEARSIGN COMBUSTION CORP</issuerName>
        <issuerTradingSymbol>CLIR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000941593</rptOwnerCik>
            <rptOwnerName>BELL LON E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>12870 INTERURBAN AVENUE SOUTH</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SEATTLE</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98168</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option to Purchase Common Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>1.00</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-05-09</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>17000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2029-04-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>17000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On May 9, 2019, the Issuer's board of directors approved compensation to be paid to the Issuer's non-executive directors for services provided to the Issuer during the first quarter of 2019.  The reporting person is a non-executive director.   The number of option shares awarded was based on the services provided by the director.  These services include, depending on the individual, Board participation, committee participation, committee chair responsibilities and lead director responsibilities, if any.  The shares of common stock are issued from the Company's 2011 Equity Incentive Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Lon E. Bell</signatureName>
        <signatureDate>2019-05-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
