<SEC-DOCUMENT>0001104659-24-008421.txt : 20240130
<SEC-HEADER>0001104659-24-008421.hdr.sgml : 20240130
<ACCEPTANCE-DATETIME>20240130204227
ACCESSION NUMBER:		0001104659-24-008421
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240126
FILED AS OF DATE:		20240130
DATE AS OF CHANGE:		20240130

REPORTING-OWNER:	

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

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37990
		FILM NUMBER:		24580330

	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]
		ORGANIZATION NAME:           	03 Life Sciences
		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>tm244628-5_4seq1.xml
<DESCRIPTION>OWNERSHIP DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2024-01-26</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>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-01-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5086</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>414480</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By HealthCare Ventures IX, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2024-01-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Restricted Stock Units convert into common stock on a one-for-one basis.</footnote>
        <footnote id="F2">The share numbers reflected in Tables I and II have been adjusted to take into account a 10-for-1 reverse stock split of the Company's common stock that was effected on June 20, 2023.</footnote>
        <footnote id="F3">The reporting person is a Managing Director of HealthCare Partners IX, LLC which is the General Partner of HealthCare Partners IX, L.P., which is the General Partner of HealthCare Ventures IX, L.P. The reporting person beneficially owns and shares voting and dispositive power with respect to all of the securities owned by HealthCare Ventures IX, L.P. and disclaims beneficial ownership of these shares except to the extent of his proportionate pecuniary interest therein.</footnote>
        <footnote id="F4">On January 26, 2021, the reporting person was granted 5,000 Restricted Stock Units, vesting on January 26, 2024 or upon a change of control, whichever is earlier, provided that the grantee continues to be employed by, or provides service to the Company from the grant date to the vesting date of the Restricted Stock Units. At such time as the Restricted Stock Units vest, one share of Common Stock shall be issued automatically in settlement of each Restricted Stock Unit.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Douglas E. Onsi, as attorney-in-fact for Christopher Mirabelli</signatureName>
        <signatureDate>2024-01-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
