<SEC-DOCUMENT>0001104659-21-030939.txt : 20210302
<SEC-HEADER>0001104659-21-030939.hdr.sgml : 20210302
<ACCEPTANCE-DATETIME>20210302192929
ACCESSION NUMBER:		0001104659-21-030939
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210226
FILED AS OF DATE:		20210302
DATE AS OF CHANGE:		20210302

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Penn Mark Jeffery
		CENTRAL INDEX KEY:			0001771735

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13718
		FILM NUMBER:		21706211

	MAIL ADDRESS:	
		STREET 1:		1808 I STREENET, NW
		STREET 2:		6TH FLOOR
		CITY:			WASHINGTON
		STATE:			DC
		ZIP:			20006

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MDC PARTNERS INC
		CENTRAL INDEX KEY:			0000876883
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ADVERTISING AGENCIES [7311]
		IRS NUMBER:				980364441
		STATE OF INCORPORATION:			A6
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE WORLD TRADE CENTER, FLOOR 65
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10007
		BUSINESS PHONE:		646 429 1800

	MAIL ADDRESS:	
		STREET 1:		ONE WORLD TRADE CENTER, FLOOR 65
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10007

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MDC CORP INC
		DATE OF NAME CHANGE:	20001204

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MDC COMMUNICATIONS CORP
		DATE OF NAME CHANGE:	19961028

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MDC CORPORATION
		DATE OF NAME CHANGE:	19950419
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>tm218483-1_4seq1.xml
<DESCRIPTION>OWNERSHIP DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-02-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000876883</issuerCik>
        <issuerName>MDC PARTNERS INC</issuerName>
        <issuerTradingSymbol>MDCA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001771735</rptOwnerCik>
            <rptOwnerName>Penn Mark Jeffery</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THE STAGWELL GROUP LLC,</rptOwnerStreet1>
            <rptOwnerStreet2>1808 I STREET, NW 6TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>WASHINGTON</rptOwnerCity>
            <rptOwnerState>DC</rptOwnerState>
            <rptOwnerZipCode>20006</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Subordinate Voting Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>28449</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>574051</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Subordinate Voting Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14400714</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">577,500 shares of Restricted Stock (Class A Shares) of the Issuer were awarded to the Reporting Person on November 4, 2019, subject to achievement of financial performance targets and continued employment. 28,449 of these shares were forfeited on February 26, 2021 as a result of partial achievement of the financial performance targets. The remaining shares will vest on December 31, 2022, subject to continued employment.</footnote>
        <footnote id="F2">Includes 549,051 shares of unvested Restricted Stock (Class A Shares) of the Issuer.</footnote>
        <footnote id="F3">The Reporting Person is the controlling person of The Stagwell Group LLC (&quot;Stagwell&quot;). Stagwell directly holds 115,000 Class A Shares of the Issuer. Stagwell is the manager of Stagwell Agency Holdings LLC, which directly holds 14,285,714 Class A Shares of the Issuer. The Reporting Person disclaims beneficial ownership of the securities reported herein except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of, or has any pecuniary interest in, such securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Mark Penn</signatureName>
        <signatureDate>2021-03-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
