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    <ACCEPTANCE-DATETIME>20210329173318
    ACCESSION NUMBER:		0001104659-21-043400
    CONFORMED SUBMISSION TYPE:	S-4/A
    PUBLIC DOCUMENT COUNT:		29
    FILED AS OF DATE:		20210330
    DATE AS OF CHANGE:		20210329

    FILER:

    	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

    	FILING VALUES:
    		FORM TYPE:		S-4/A
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-252829
    		FILM NUMBER:		21782788

    	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
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    <DESCRIPTION>S-4/A
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    <TYPE>EX-3.3
    <SEQUENCE>2
    <FILENAME>tm214718d4_ex3-3.htm
    <DESCRIPTION>EXHIBIT 3.3
    <TEXT>
    Document 2 - file: tm214718d4_ex3-3.htm

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    <TYPE>EX-5.1
    <SEQUENCE>3
    <FILENAME>tm214718d4_ex5-1.htm
    <DESCRIPTION>EXHIBIT 5.1
    <TEXT>
    Document 3 - file: tm214718d4_ex5-1.htm

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    <SEQUENCE>4
    <FILENAME>tm214718d4_ex8-1.htm
    <DESCRIPTION>EXHIBIT 8.1
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    Document 4 - file: tm214718d4_ex8-1.htm

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    <SEQUENCE>5
    <FILENAME>tm214718d4_ex8-2.htm
    <DESCRIPTION>EXHIBIT 8.2
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    Document 5 - file: tm214718d4_ex8-2.htm

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    <TYPE>EX-23.1
    <SEQUENCE>6
    <FILENAME>tm214718d4_ex23-1.htm
    <DESCRIPTION>EXHIBIT 23.1
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    Document 6 - file: tm214718d4_ex23-1.htm

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    <SEQUENCE>7
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    <DESCRIPTION>EXHIBIT 23.2
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    <SEQUENCE>8
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    <DESCRIPTION>GRAPHIC
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    <DESCRIPTION>GRAPHIC
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    <SEQUENCE>26
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