<SEC-DOCUMENT>0001104659-23-095364.txt : 20230825
<SEC-HEADER>0001104659-23-095364.hdr.sgml : 20230825
<ACCEPTANCE-DATETIME>20230825163101
ACCESSION NUMBER:		0001104659-23-095364
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230823
FILED AS OF DATE:		20230825
DATE AS OF CHANGE:		20230825

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mirabelli Christopher
		CENTRAL INDEX KEY:			0001262326

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37990
		FILM NUMBER:		231208808

	MAIL ADDRESS:	
		STREET 1:		55 CAMBRIDGE PARKWAY
		STREET 2:		SUITE 301
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

	FORMER NAME:	
		FORMER CONFORMED NAME:	MIRAELLI CHRISTOPHER
		DATE OF NAME CHANGE:	20030904

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LEAP THERAPEUTICS, INC.
		CENTRAL INDEX KEY:			0001509745
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				274412575
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		47 THORNDIKE STREET
		STREET 2:		SUITE B1-1
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		617 252 4343

	MAIL ADDRESS:	
		STREET 1:		47 THORNDIKE STREET
		STREET 2:		SUITE B1-1
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Dekkun Corp
		DATE OF NAME CHANGE:	20110107
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>tm2324823-10_4seq1.xml
<DESCRIPTION>OWNERSHIP DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2023-08-23</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001509745</issuerCik>
        <issuerName>LEAP THERAPEUTICS, INC.</issuerName>
        <issuerTradingSymbol>LPTX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001262326</rptOwnerCik>
            <rptOwnerName>Mirabelli Christopher</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O LEAP THERAPEUTICS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>47 THORNDIKE STREET SUITE B1-1</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02141</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman of the Board</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.21</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2023-08-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>70000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2033-08-23</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>70000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>70000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Option was granted pursuant to Leap's 2022 Equity Incentive Plan, as amended. By its terms, the Option shall vest and become exercisable for the shares underlying the Option in a series of 36 equal monthly installments for so long as the reporting person continues to be employed by or provides service to the Company, with the first of such monthly installments vesting on September 23, 2023 and an additional of such monthly installments vesting on the 23rd day of each calendar month thereafter.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Douglas E. Onsi, as attorney-in-fact for Christopher Mirabelli</signatureName>
        <signatureDate>2023-08-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
