SecProbe.io

May 16, 2011

Via U.S. Mail and Facsimile (212-415-3530)

Mr. Randall J. Weisenburger
Executive Vice President and Chief Financial Officer
Omnicom Group Inc.
437 Madison Avenue  New York, NY 10022

RE: Omnicom Group Inc.
Form 10-K for the fiscal year ended December 31, 2010
Filed February 23, 2011 File No. 001-10551

From 10-Q for the quarter ended March 31, 2011
Filed April 29, 2011

Dear Mr. Weisenburger:

 We have limited our review to only your fina ncial statements and related disclosures and
do not intend to expand our review to other portions of your documents.  Please provide us with
the requested information so we may better understand your disclosure.

Please respond to this letter within te n business days by providing the requested
information or by advising us when you will provide the requested response.  If you do not believe our comments apply to your facts and circum stances, please tell us w hy in your response.
 After reviewing the information you provide in response to these comments, we may
have additional comments.               Form 10-K

Financial Statements
6 Debt
Convertible Debt, page F-17

1. Refer to the first three para graphs of page F-18, which indicate that your 2032 and 2038
Convertible Notes include conve rsion features which are to  be satisfied by paying the
initial principal amount of the note in cash and the balance of the conversion value in
cash or shares, at your option.  Tell us how you applied the guida nce of ASC 470-20-05-
13 regarding cash conversions of convertib le debt to your 2032 and 2038 Convertible
Notes.

Mr. Randall J. Weisenburger
Omnicom Group Inc.
May 16, 2011
Page 2

Please file all correspondence over EDGAR.  We urge all persons who are responsible
for the accuracy and adequacy of the disclosure in  the filing to be certain  that the filing includes
the information the Securities Exchange Act of 1934 and all applicable Exchange Act rules
require.  Since the company and its management  are in possession of a ll facts relating to a
company’s disclosure, they are responsible for th e accuracy and adequacy of  the disclosures they
have made.                In responding to our comments, please provide a written statement from the company
acknowledging that:

 the company is responsible for the adequacy an d accuracy of the disclo sure in the filing;

 staff comments or changes to disclosure in response to staff comments do not foreclose
the Commission from taking any action with respect to the filing; and

 the company may not assert staff comments as  a defense in any proceeding initiated by
the Commission or any person under the federa l securities laws of  the United States.
 You may contact Joseph M. Kempf, Senior Staff Account ant, at (202) 551-3352 or
Carlos Pacho, Senior Assistant Chief Account ant, at (202) 551-3835 if you have questions
regarding comments on the financial statements and related matters.  Please contact me at (202)
551-3810 with any other questions.
Sincerely,    Larry Spirgel Assistant Director