<SEC-DOCUMENT>0001209191-21-053380.txt : 20210825
<SEC-HEADER>0001209191-21-053380.hdr.sgml : 20210825
<ACCEPTANCE-DATETIME>20210825194233
ACCESSION NUMBER:		0001209191-21-053380
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210823
FILED AS OF DATE:		20210825
DATE AS OF CHANGE:		20210825

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MPM Oncology Impact Management LP
		CENTRAL INDEX KEY:			0001687078
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39856
		FILM NUMBER:		211208372

	BUSINESS ADDRESS:	
		STREET 1:		450 KENDALL STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		6174259200

	MAIL ADDRESS:	
		STREET 1:		450 KENDALL STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			UBS Oncology Impact Fund L.P.
		CENTRAL INDEX KEY:			0001691428
		STATE OF INCORPORATION:			E9
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39856
		FILM NUMBER:		211208375

	BUSINESS ADDRESS:	
		STREET 1:		450 KENDALL STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		617-425-9200

	MAIL ADDRESS:	
		STREET 1:		450 KENDALL STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MPM Oncology Impact Management GP LLC
		CENTRAL INDEX KEY:			0001721035
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39856
		FILM NUMBER:		211208373

	BUSINESS ADDRESS:	
		STREET 1:		450 KENDALL STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		6174259200

	MAIL ADDRESS:	
		STREET 1:		450 KENDALL STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Oncology Impact Fund (Cayman) Management L.P.
		CENTRAL INDEX KEY:			0001721036
		STATE OF INCORPORATION:			E9
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39856
		FILM NUMBER:		211208374

	BUSINESS ADDRESS:	
		STREET 1:		450 KENDALL STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		6174259200

	MAIL ADDRESS:	
		STREET 1:		450 KENDALL STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Cullinan Oncology, Inc.
		CENTRAL INDEX KEY:			0001789972
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				813867811
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE MAIN STREET
		STREET 2:		SUITE 520
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		617-410-4650

	MAIL ADDRESS:	
		STREET 1:		ONE MAIN STREET
		STREET 2:		SUITE 520
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Cullinan Management, Inc.
		DATE OF NAME CHANGE:	20210107

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Cullinan Oncology, LLC
		DATE OF NAME CHANGE:	20191001
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-08-23</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001789972</issuerCik>
        <issuerName>Cullinan Oncology, Inc.</issuerName>
        <issuerTradingSymbol>CGEM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001691428</rptOwnerCik>
            <rptOwnerName>UBS Oncology Impact Fund L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT LLC</rptOwnerStreet1>
            <rptOwnerStreet2>450 KENDALL STREET</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001721036</rptOwnerCik>
            <rptOwnerName>Oncology Impact Fund (Cayman) Management L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT LLC</rptOwnerStreet1>
            <rptOwnerStreet2>450 KENDALL STREET</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001721035</rptOwnerCik>
            <rptOwnerName>MPM Oncology Impact Management GP LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT LLC</rptOwnerStreet1>
            <rptOwnerStreet2>450 KENDALL STREET</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001687078</rptOwnerCik>
            <rptOwnerName>MPM Oncology Impact Management LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT LLC</rptOwnerStreet1>
            <rptOwnerStreet2>450 KENDALL STREET</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-08-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>53359</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>29.11</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7858018</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-08-24</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>50822</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>29.48</value>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7807196</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-08-25</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1713</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>29.09</value>
                    <footnoteId id="F6"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7805483</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Transaction effected pursuant to a plan established pursuant to Rule 10b5-1 on June 23, 2021.</footnote>
        <footnote id="F2">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $29.00 to $29.41 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
        <footnote id="F3">These securities are owned directly by UBS Oncology Impact Fund LP (&quot;OIF&quot;). The general partner of OIF is Oncology Impact Fund (Cayman) Management L.P. (&quot;OIF GP&quot;). The general partner of OIF GP is MPM Oncology Impact Management L.P. The general partner of MPM Oncology Impact Management L.P. is MPM Oncology Impact Management GP LLC. Dr. Ansbert Gadicke is a member of the Issuer's board of directors and is a managing member and the managing director of MPM Oncology Impact Management GP LLC.</footnote>
        <footnote id="F4">Each of the Reporting Persons disclaims beneficial ownership of the securities except to the extent of its pecuniary interest therein.</footnote>
        <footnote id="F5">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $29.15 to $29.715 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
        <footnote id="F6">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $29.01 to $29.47 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Ansbert Gadicke, managing director of MPM Oncology Impact Management GP LLC, the general partner of MPM Oncology Impact Management LP, the general partner of Oncology Impact Fund (Cayman) Management L.P., the GP of UBS Oncology Impact Fund L.P</signatureName>
        <signatureDate>2021-08-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Ansbert Gadicke, managing director of MPM Oncology Impact Management GP LLC, the general partner of MPM Oncology Impact Management LP, the general partner of Oncology Impact Fund (Cayman) Management L.P.</signatureName>
        <signatureDate>2021-08-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Ansbert Gadicke, managing director of MPM Oncology Impact Management GP LLC</signatureName>
        <signatureDate>2021-08-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Ansbert Gadicke, managing director of MPM Oncology Impact Management GP LLC, the general partner of MPM Oncology Impact Management LP</signatureName>
        <signatureDate>2021-08-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
