<SEC-DOCUMENT>0001104659-25-016240.txt : 20250221
<SEC-HEADER>0001104659-25-016240.hdr.sgml : 20250221
<ACCEPTANCE-DATETIME>20250221190039
ACCESSION NUMBER:		0001104659-25-016240
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240520
FILED AS OF DATE:		20250221
DATE AS OF CHANGE:		20250221

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hinds Brent
		CENTRAL INDEX KEY:			0001888082
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35521
		FILM NUMBER:		25653694

	MAIL ADDRESS:	
		STREET 1:		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>
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        <issuerName>ClearSign Technologies Corp</issuerName>
        <issuerTradingSymbol>CLIR</issuerTradingSymbol>
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            <rptOwnerName>Hinds Brent</rptOwnerName>
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            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TULSA</rptOwnerCity>
            <rptOwnerState>OK</rptOwnerState>
            <rptOwnerZipCode>74133</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
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    <footnotes>
        <footnote id="F1">Reflects the vesting of 2,627 performance-based restricted stock units (&quot;PRSUs&quot;) granted to the reporting person on February 22, 2024, into an equal number of shares of the Company's common stock, without the payment of any consideration, pursuant to the ClearSign Technologies Corporation 2021 Equity Incentive Plan (the &quot;2021 Plan&quot;).</footnote>
        <footnote id="F2">Represents the payment of the reporting person's tax liability by withholding shares in connection with the vesting of 2,627 PRSUs on May 20, 2024, and calculated based on the closing price of the Company's common stock, as reported on Nasdaq Stock Market, on May 20, 2024 of $0.78.</footnote>
        <footnote id="F3">Reflects the vesting of 10,127 restricted stock units (&quot;RSUs&quot;) out of the 30,380 RSUs granted to the reporting person on February 2, 2023, into an equal number of shares of the Company's common stock, without the payment of any consideration, pursuant to the 2021 Plan.</footnote>
        <footnote id="F4">Represents the payment of the reporting person's tax liability by withholding shares in connection with the vesting of 10,127 RSUs on February 2, 2025, and calculated based on the closing price of the Company's common stock, as reported on Nasdaq Stock Market, on February 2, 2025 of $1.20.</footnote>
        <footnote id="F5">On February 22, 2024, the reporting person was granted a one-time bonus of 2,627 PRSUs, and each PRSU represents a right to receive one share of common stock or the cash equivalent thereof.</footnote>
        <footnote id="F6">The PRSUs granted on February 22, 2024, vested on May 20, 2024, upon the achievement of certain performance targets established by the Company's compensation committee of the board of directors for the year ended December 31, 2024.</footnote>
        <footnote id="F7">On February 2, 2023, the reporting person was granted a one-time bonus of 30,380 RSUs, and each RSU represents a right to receive one share of common stock or the cash equivalent thereof.</footnote>
        <footnote id="F8">The RSUs granted on February 2, 2023, vest in three equal annual installments that commenced on February 2, 2024.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Brent Hinds</signatureName>
        <signatureDate>2025-02-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
