Stagwell (STGW) 8-K Regulation FD Disclosure

Exhibit 99.1

Beginning with fourth quarter 2009 results, the Company will report two segments, Strategic Marketing Services Group and Performance Marketing Services Group:

1.  Strategic Marketing Services Group — This segment will include all integrated advertising agencies and strategic consulting services firms, including:

Allard Johnson

Attention

Bruce Mau Design

Colle + McVoy

Crispin Porter + Bogusky

Fletcher Martin

Hello Design

Henderson Bas

HL Group

Kirshenbaum Bond Senecal + Partners

Mono

Redscout

Skinny

Veritas

VitroRobertson

Yamamoto Moss MacKenzie

Zig

2.  Performance Marketing Services Group — This segment will predominantly include firms that use data analytics, provide consumer insights, or one-to-one consumer engagements to satisfy the growing need for targetable, measurable solutions and cost effective means of driving increasing return on marketing investment for clients, including:

Accent

Bryan Mills

Computer Composition Corp

Northstar Research Partners

Onbrand

6 Degrees

Source Marketing

Targetcom

Below are reclassified financials for each of the first three quarters in 2009 and 2008 and for the nine month-periods ended September 30, 2009 and 2008.

1

Summary financial information concerning the Company’s reclassified reportable segments are shown in the following tables:

Three Months Ended March 31, 2009

(thousands of United States dollars)  

	Strategic Marketing Services			Performance Marketing Services			Corporate			Total
Revenue	$	84,463		$	42,275		$	—		$	126,738
Cost of services sold		52,680			33,199			—			85,879
Office and general expenses		19,612			7,628			3,912			31,152
Depreciation and amortization		5,372			2,127			94			7,593
Operating Profit/(Loss)		6,799			(679	)		(4,006	)		2,114
Other Income (Expense):
Other income, net											2,629
Interest expense, net											(3,558	)
Income from continuing operations before income taxes, equity in affiliates											1,185
Income tax expense											615
Income from continuing operations before equity in affiliates											570
Equity in earnings of non-consolidated affiliates											93
Income from continuing operations											663
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes											(252)
Net Income											411
Net income attributable to the noncontrolling interests		(676	)		294			—			(382	)
Net income attributable to MDC Partners Inc.										$	29
Non cash stock based compensation	$	433		$	190		$	1,274		$	1,897
Supplemental Segment Information:
Capital expenditures	$	772		$	39		$	19		$	830
Goodwill and intangibles	$	223,022		$	57,505		$	—		$	280,527
Total assets	$	377,113		$	120,526		$	38,446		$	536,085

2

Three Months Ended March 31, 2008

(thousands of United States dollars)  

	Strategic Marketing Services			Performance Marketing Services Group			Corporate			Total
Revenue	$	86,146		$	54,756		$	—		$	140,902
Cost of services sold		55,146			40,373			—			95,519
Office and general expenses		21,153			8,919			4,383			34,455
Depreciation and amortization		7,464			2,244			68			9,776
Operating Profit/(Loss)		2,383			3,220			(4,451	)		1,152
Other Income (Expense):
Other income, net											3,627
Interest expense, net											(3,444	)
Income from continuing operations before income taxes, equity in affiliates											1,335
Income tax recovery											292
Income from continuing operations before equity in affiliates											1,627
Equity in earnings of non-consolidated affiliates											140
Income from continuing operations											1,767
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes											(3,036	)
Net Loss											(1,269	)
Net income attributable to the noncontrolling interests		(1,163	)		(962	)		—			(2,125	)
Net loss attributable to MDC Partners Inc.										$	(3,394	)
Non cash stock based compensation	$	446		$	284		$	1,268		$	1,998
Supplemental Segment Information:
Capital expenditures	$	2,815		$	1,334		$	28		$	4,177
Goodwill and intangibles	$	212,196		$	63,054		$	—		$	275,250
Total assets	$	379,445		$	146,604		$	13,641		$	539,690

3

Three Months Ended June 30, 2009

(thousands of United States dollars)  

	Strategic Marketing Services			Performance Marketing Services			Corporate			Total
Revenue	$	88,248		$	46,634		$	—		$	134,882
Cost of services sold		52,760			35,478			—			88,238
Office and general expense		18,517			7,517			4,139			30,173
Depreciation and amortization		5,480			2,043			81			7,604
Operating Profit/(Loss)		11,491			1,596			(4,220	)		8,867
Other Income (Expense):
Other expense, net											(2,541	)
Interest expense, net											(3,653	)
Income from continuing operations before income taxes, equity in affiliates											2,673
Income tax expense											1,608
Income from continuing operations before equity in affiliates											1,065
Equity in earnings of non-consolidated affiliates											105
Income from continuing operations											1,170
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes											(108	)
Net Income											1,062
Net income attributable to the noncontrolling interests		(978	)		(5	)		—			(983	)
Net income attributable to MDC Partners Inc.										$	79
Non cash stock based compensation	$	371		$	184		$	1,490		$	2,045
Supplemental Segment Information:
Capital expenditures	$	676		$	540		$	41		$	1,257
Goodwill and intangibles	$	221,468		$	57,954		$	—		$	279,422
Total assets	$	357,067		$	120,464		$	66,749		$	544,280

4

Three Months Ended June 30, 2008

(thousands of United States dollars)  

	Strategic Marketing Services			Performance Marketing Services			Corporate			Total
Revenue	$	96,405		$	60,544		$	—		$	156,949
Cost of services sold		59,178			43,155			—			102,333
Office and general expense		22,005			9,585			4,845			36,435
Depreciation and amortization		6,118			2,398			69			8,585
Operating Profit/(Loss)		9,104			5,406			(4,914	)		9,596
Other Income (Expense):
Other expense, net											(501	)
Interest expense, net											(3,228	)
Income from continuing operations before income taxes, equity in affiliates											5,867
Income tax expense											4,485
Income from continuing operations before equity in affiliates											1,382
Equity in earnings of non-consolidated affiliates											81
Income from continuing operations											1,483
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes											(2,891	)
Net loss											(1,428	)
Net loss attributable to the noncontrolling interests		(1,955	)		(1,089	)		—			(3,044	)
Net loss attributable to MDC Partners Inc.										$	(4,472	)
Non cash stock based compensation	$	571		$	257		$	1,035		$	1,863
Supplemental Segment Information:
Capital expenditures	$	2,934		$	1,475		$	8		$	4,417
Goodwill and intangibles	$	212,679		$	62,659		$	—		$	275,338
Total assets	$	390,686		$	143,775		$	18,210		$	552,671

5

Three Months Ended September 30, 2009

(thousands of United States dollars)  

	Strategic Marketing Services			Performance Marketing Services			Corporate			Total
Revenue	$	92,680		$	41,945		$	—		$	134,625
Cost of services sold		54,023			31,503			—			85,526
Office and general expenses		19,105			7,578			4,718			31,401
Depreciation and amortization		5,386			2,013			115			7,514
Operating Profit/(Loss)		14,166			851			(4,833	)		10,184
Other Income (Expense):
Other expense, net											(3,080	)
Interest expense, net											(3,775	)
Income from continuing operations before income taxes, equity in affiliates											3,329
Income tax expense											1,149
Income from continuing operations before equity in affiliates											2,180
Equity in earnings of non-consolidated affiliates											60
Income from continuing operations											2,240
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes											—
Net Income											2,240
Net income attributable to the noncontrolling interests		(2,073	)		(131	)		—			(2,204	)
Net income attributable to MDC Partners Inc.										$	36
Non cash stock based compensation	$	705		$	292		$	1,234		$	2,231
Supplemental Segment Information:
Capital expenditures	$	853		$	315		$	33		$	1,201
Goodwill and intangibles	$	232,580		$	58,366		$	—		$	290,946
Total assets	$	393,818		$	117,603		$	68,817		$	580,238

6

Three Months Ended September 30, 2008

(thousands of United States dollars)  

	Strategic Marketing Services			Performance Marketing Services			Corporate			Total
Revenue	$	88,246		$	53,843		$	—		$	142,089
Cost of services sold		54,157			40,402			—			94,559
Office and general expenses		19,967			8,998			2,899			31,864
Depreciation and amortization		5,055			2,303			69			7,427
Operating Profit/(Loss)		9,067			2,140			(2,968	)		8,239
Other Income (Expense):
Other income, net											2,418
Interest expense, net											(3,117	)
Income from continuing operations before income taxes, equity in affiliates											7,540
Income tax expense											2,222
Income from continuing operations before equity in affiliates											5,318
Equity in earnings of non-consolidated affiliates											69
Income from continuing operations											5,387
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes											(771	)
Net Income											4,616
Net income attributable to the noncontrolling interests		(1,103	)		(263	)		—			(1,366	)
Net income attributable to MDC Partners Inc.										$	3,250
Non cash stock based compensation	$	475		$	205		$	1,149		$	1,829
Supplemental Segment Information:
Capital expenditures	$	1,380		$	439		$	23		$	1,842
Goodwill and intangibles	$	209,908		$	61,733		$	—		$	271,641
Total assets	$	376,009		$	142,907		$	9,799		$	528,715

7

Nine Months Ended September 30, 2009

(thousands of United States dollars)  

	Strategic Marketing Services			Performance Marketing Services		Corporate			Total
Revenue	$	265,392		$	130,854	$	—		$	396,246
Cost of services sold		159,464			100,180		—			259,644
Office and general expenses		57,234			22,723		12,769			92,726
Depreciation and amortization		16,239			6,184		288			22,711
Operating Profit/(Loss)		32,455			1,767		(13,057	)		21,165
Other Income (Expense):
Other expense, net										(2,991	)
Interest expense, net										(10,987	)
Income from continuing operations before income taxes, equity in affiliates										7,187
Income tax expense										3,373
Income from continuing operations before equity in affiliates										3,814
Equity in earnings of non-consolidated affiliates										258
Income from continuing operations										4,072
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes										(361	)
Net Income										3,711
Net income attributable to the noncontrolling interests		(3,727	)		158		—			(3,569	)
Net income attributable to MDC Partners Inc.									$	142
Non cash stock based compensation	$	1,509		$	666	$	3,998		$	6,173
Supplemental Segment Information:
Capital expenditures	$	2,302		$	894	$	92		$	3,288
Goodwill and intangibles	$	232,580		$	58,366	$	—		$	290,946
Total assets	$	393,818		$	117,603	$	68,817		$	580,238

8

Nine Months Ended September 30, 2008

(thousands of United States dollars)  

	Strategic Marketing Services			Performance Marketing Services			Corporate			Total
Revenue	$	270,797		$	169,143		$	—		$	439,940
Cost of services sold		168,481			123,929			—			292,410
Office and general expenses		63,125			27,502			12,127			102,754
Depreciation and amortization		18,639			6,946			204			25,789
Operating Profit/(Loss)		20,552			10,766			(12,331	)		18,987
Other Income (Expense):
Other income, net											5,545
Interest expense, net											(9,790	)
Income from continuing operations before income taxes, equity in affiliates											14,742
Income tax expense											6,415
Income from continuing operations before equity in affiliates											8,327
Equity in earnings of non-consolidated affiliates											290
Income from continuing operations											8,617
Loss from discontinued operations attributable to MDC Partners Inc., net of taxes											(6,698	)
Net Income											1,919
Net income attributable to the noncontrolling interests		(4,220	)		(2,313	)		—			(6,533	)
Net loss attributable to MDC Partners Inc.										$	(4,614	)
Non cash stock based compensation	$	1,492		$	746		$	3,452		$	5,690
Supplemental Segment Information:
Capital expenditures	$	7,127		$	3,247		$	60		$	10,434
Goodwill and intangibles	$	209,908		$	61,733		$			$	271,641
Total assets	$	376,009		$	142,907		$	9,799		$	528,715

9