<SEC-DOCUMENT>0001104659-24-027573.txt : 20240226
<SEC-HEADER>0001104659-24-027573.hdr.sgml : 20240226
<ACCEPTANCE-DATETIME>20240226170108
ACCESSION NUMBER:		0001104659-24-027573
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240222
FILED AS OF DATE:		20240226
DATE AS OF CHANGE:		20240226

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Deller Colin James
		CENTRAL INDEX KEY:			0001766480
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35521
		FILM NUMBER:		24679962

	MAIL ADDRESS:	
		STREET 1:		C/O CLEARSIGN COMBUSTION CORP.
		STREET 2:		12870 INTERURBAN AVENUE SOUTH
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98168

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ClearSign Technologies Corp
		CENTRAL INDEX KEY:			0001434524
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL INSTRUMENTS FOR MEASUREMENT, DISPLAY, AND CONTROL [3823]
		ORGANIZATION NAME:           	08 Industrial Applications and Services
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		8023 E. 63RD PLACE, SUITE 101
		CITY:			TULSA
		STATE:			OK
		ZIP:			74133
		BUSINESS PHONE:		(918) 236-6461

	MAIL ADDRESS:	
		STREET 1:		8023 E. 63RD PLACE, SUITE 101
		CITY:			TULSA
		STATE:			OK
		ZIP:			74133

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CLEARSIGN COMBUSTION CORP
		DATE OF NAME CHANGE:	20080507
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>tm247292-1_4seq1.xml
<DESCRIPTION>OWNERSHIP DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2024-02-22</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001434524</issuerCik>
        <issuerName>ClearSign Technologies Corp</issuerName>
        <issuerTradingSymbol>CLIR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001766480</rptOwnerCik>
            <rptOwnerName>Deller Colin James</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>8023 E. 63RD PLACE, SUITE 101</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TULSA</rptOwnerCity>
            <rptOwnerState>OK</rptOwnerState>
            <rptOwnerZipCode>74133</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-02-22</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>131121</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>186408</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-02-22</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>65102</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.06</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>121306</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents a one-time bonus grant to reporting person for services as an executive officer for the year ended December 31, 2023. The number of shares awarded is based on the closing price of the Company's common stock on February 22, 2024 of $1.06.</footnote>
        <footnote id="F2">Represents the payment of the reporting person's tax liability by withholding shares incident to the receipt of the Company's common stock issued on February 22, 2024 based on the closing price of the Company's common stock on February 22, 2024 of $1.06.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Colin J. Deller</signatureName>
        <signatureDate>2024-02-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
