PROSPECTUS SUPPLEMENT
(To Prospectus Dated March 11, 1997)
OMNICOM GROUP INC.
$218,500,000 Principal Amount of
4 1/4% Convertible Subordinated Debentures due 2007
(Interest Payable January 3 and July 3)
6,936,508 Shares of Common Stock
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This document supplements the Prospectus dated March 11, 1997 relating to
(i) $218,500,000 aggregate principal amount of 4 1/4% Convertible Subordinated
Debentures due 2007 (the "Debentures") of Omnicom Group Inc., a New York
corporation ("Omnicom" or the "Company"), and (ii) 6,936,508 shares of Common
Stock, par value $0.50 per share (the "Common Stock") of the Company which are
initially issuable upon conversion of the Debentures plus additional
indeterminate number of shares of Common Stock as may become issuable upon
conversion of the Debentures as a result of adjustments to the conversion price
(the "Shares"). The Debentures were initially acquired from the Company by
Morgan Stanley & Co. Incorporated in January 1997 in connection with a private
offering. This Prospectus Supplement is incorporated by reference into the
Prospectus, and all terms used herein shall have the meaning assigned to them in
the Prospectus. On October 13, 1998 the closing price of the Common Stock as
reported on the New York Stock Exchange was $41.5625 per share. The Common Stock
is traded under the symbol "OMC".
In accordance with the Section of the Prospectus entitled "Selling
Securityholders" (which appears on pages 19 and 20 of the Prospectus), the
following information is provided with respect to the beneficial owners of the
Debentures:
Principal Amount Principal Amount
of Debentures of Debentures
Beneficially to be Offered
Name of Selling Securityholder(s) Owned for Sale
- --------------------------------- --------------- ---------------
Baptist Health of South Florida $ 251,000 $ 251,000
Boston Museum of Fine Arts 106,000 106,000
Dunham & Associates II 77,000 77,000
Dunham & Associates III 30,000 30,000
Engineers Joint Pension Fund 397,000 397,000
Goldman, Sachs & Co. 1,000,000 1,000,000
Nicholas-Applegate Convertible
Fund 3,441,000 3,441,000
Physicians Life 235,000 235,000
San Diego City Retirement 785,000 785,000
San Diego County Convertible 3,351,000 3,351,000
Tennessee Consolidated Retirement
System 2,500,000 2,500,000
Wake Forest University 626,000 626,000
The Debentures being offered by the Selling Securityholders hereby
represent all of the Debentures beneficially owned by the Selling
Securityholders as of October 13, 1998. Except for the purchase of the
Debentures, none of the Selling Securityholders has had a material relationship
with the Company or any of its affiliates within the past three years.
THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SECURITIES
AND EXCHANGE COMMISSION OR ANY STATE SECURITY COMMISSION NOR HAS THE SECURITIES
AND EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION PASSED UPON THE
ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL OFFENSE.
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The date of this Prospectus Supplement is October 15, 1998.
