<SEC-DOCUMENT>0001104659-18-037319.txt : 20180531
<SEC-HEADER>0001104659-18-037319.hdr.sgml : 20180531
<ACCEPTANCE-DATETIME>20180531214323
ACCESSION NUMBER:		0001104659-18-037319
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180529
FILED AS OF DATE:		20180531
DATE AS OF CHANGE:		20180531

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Polaris Venture Management Co. VI, L.L.C.
		CENTRAL INDEX KEY:			0001665594
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38501
		FILM NUMBER:		18873313

	BUSINESS ADDRESS:	
		STREET 1:		ONE MARINA PARK DRIVE
		STREET 2:		10TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02210
		BUSINESS PHONE:		(855) 787-3500

	MAIL ADDRESS:	
		STREET 1:		ONE MARINA PARK DRIVE
		STREET 2:		10TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02210

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Polaris Venture Partners VI, L.P.
		CENTRAL INDEX KEY:			0001493463
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38501
		FILM NUMBER:		18873312

	BUSINESS ADDRESS:	
		STREET 1:		ONE MARINA PARK DRIVE, 10TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02210
		BUSINESS PHONE:		781-290-0770

	MAIL ADDRESS:	
		STREET 1:		ONE MARINA PARK DRIVE, 10TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02210

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Polaris Venture Partners Founders' Fund VI, L.P.
		CENTRAL INDEX KEY:			0001575691
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38501
		FILM NUMBER:		18873311

	BUSINESS ADDRESS:	
		STREET 1:		ONE MARINA PARK DRIVE, 10TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02210
		BUSINESS PHONE:		885-787-3500

	MAIL ADDRESS:	
		STREET 1:		ONE MARINA PARK DRIVE, 10TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02210

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Scholar Rock Holding Corp
		CENTRAL INDEX KEY:			0001727196
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				823750435
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		620 MEMORIAL DRIVE, 2ND FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		857-259-3860

	MAIL ADDRESS:	
		STREET 1:		620 MEMORIAL DRIVE, 2ND FLOOR
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
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        </nonDerivativeTransaction>
    </nonDerivativeTable>

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                    <footnoteId id="F3"/>
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                <footnoteId id="F1"/>
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                    <value>See Footnotes</value>
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                    <footnoteId id="F3"/>
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        <derivativeTransaction>
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                <footnoteId id="F1"/>
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                    <footnoteId id="F4"/>
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        <derivativeTransaction>
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                <footnoteId id="F1"/>
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                <transactionPricePerShare>
                    <footnoteId id="F1"/>
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                <footnoteId id="F1"/>
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                <underlyingSecurityShares>
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                    <footnoteId id="F3"/>
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                <footnoteId id="F1"/>
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            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
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                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
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                <footnoteId id="F1"/>
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                <footnoteId id="F1"/>
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                </underlyingSecurityShares>
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        <derivativeTransaction>
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                <footnoteId id="F1"/>
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                <value></value>
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            <transactionAmounts>
                <transactionShares>
                    <value>744162</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
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                <footnoteId id="F1"/>
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                <footnoteId id="F1"/>
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            <underlyingSecurity>
                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>260670</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
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                    <value>0</value>
                </sharesOwnedFollowingTransaction>
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                <natureOfOwnership>
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                    <footnoteId id="F3"/>
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                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>43487</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
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                <footnoteId id="F1"/>
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        <derivativeTransaction>
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                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1979216</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
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                <footnoteId id="F1"/>
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                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
                <underlyingSecurityShares>
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                </underlyingSecurityShares>
            </underlyingSecurity>
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                    <footnoteId id="F3"/>
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                <footnoteId id="F1"/>
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                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>115659</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
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                <footnoteId id="F1"/>
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            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
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                </underlyingSecurityTitle>
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                </underlyingSecurityShares>
            </underlyingSecurity>
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                <natureOfOwnership>
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                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Series C Preferred Stock</value>
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                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
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            <transactionCoding>
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                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>808166</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
                <underlyingSecurityShares>
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                </underlyingSecurityShares>
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                </sharesOwnedFollowingTransaction>
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                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
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            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-05-29</value>
            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>47225</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                <footnoteId id="F1"/>
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                <footnoteId id="F1"/>
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                </underlyingSecurityShares>
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                    <value>0</value>
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                <directOrIndirectOwnership>
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                <natureOfOwnership>
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    <footnotes>
        <footnote id="F1">Each share of Preferred Stock automatically converted into Common Stock, for no additional payment or consideration, on a 2.8548-for-1 basis upon the closing of the Issuer's initial public offering on May 29, 2018 and had no expiration date.</footnote>
        <footnote id="F2">The reportable securities are owned directly by Polaris Venture Partners VI, L.P. (&quot;PVP VI&quot;). Polaris Venture Management Co. VI, L.L.C. (&quot;PVM VI&quot;) is the general partner of PVP VI. PVM VI is managed by its managing members, one of whom is Dr. Amir Nashat, a member of the Issuer's Board of Directors (collectively, the &quot;Managing Members&quot;). PVM VI may be deemed to have sole voting and dispositive power with respect to the shares held by PVP VI and the Managing Members may each be deemed to have shared voting and dispositive power with respect to the shares held by PVP VI.</footnote>
        <footnote id="F3">Each of PVM VI and the Managing Members disclaims beneficial ownership of these securities and this report shall not be deemed an admission that PVM VI or any of the Managing Members is a beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein.</footnote>
        <footnote id="F4">The reportable securities are owned directly by Polaris Venture Partners Founders' Fund VI, L.P. (&quot;PVPFF VI&quot;). PVM VI is the general partner of PVPFF VI. PVM VI may be deemed to have sole voting and dispositive power with respect to the shares held by PVPFF VI and the Managing Members may each be deemed to have shared voting and dispositive power with respect to the shares held by PVPFF VI. Each of PVM VI and the Managing Members disclaims beneficial ownership of these securities and this report shall not be deemed an admission that PVM VI or any of the Managing Members is a beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Max Eisenberg, Attorney-in-Fact for Polaris Venture Management Co. VI, L.L.C.</signatureName>
        <signatureDate>2018-05-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Max Eisenberg, Attorney-in-Fact for Polaris Venture Management Co. VI, L.L.C., general partner of Polaris Venture Partners VI, L.P.</signatureName>
        <signatureDate>2018-05-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Max Eisenberg, Attorney-in-Fact for Polaris Venture Management Co. VI, L.L.C., general partner of Polaris Venture Partners Founders' Fund VI, L.P.</signatureName>
        <signatureDate>2018-05-31</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
