PROSPECTUS SUPPLEMENT
(To Prospectus Dated January 28, 1998)
807,746 Shares of Common Stock
($.50 Par Value)
OMNICOM GROUP INC.
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This document supplements the Prospectus dated January 28, 1998 relating
to 807,746 shares of Common Stock, par value $.50 per share (the "Common Stock")
of the Omnicom Group Inc., a New York corporation ("Omnicom" or the "Company").
Each share of Common Stock offered hereby was issued upon exchange of an
Exchangeable Share (an "Exchangeable Share") of GPC International Holdings Inc.
("GPC"), a corporation incorporated under the laws of Canada, issued in a
private offering in Canada by GPC and the Company. The shares of Common Stock
offered hereby were initially acquired upon exchange of the Exchangeable Shares
in a private offering in Canada. 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 August 11, 1998 the closing price of the
Common Stock as reported on the New York Stock Exchange was $52.6875 per share.
The Common Stock is traded under the symbol "OMC".
The Selling Shareholder does not own in excess of 1% of the Common Stock
of the Company and since the Selling Shareholder may sell all, some or none of
the shares of Common Stock offered hereby, no estimate can be made of the
aggregate number of shares of Common Stock that will be owned by the Selling
Shareholder upon completion of the offering to which this Prospectus Supplement
relates. In accordance with the Section of the Prospectus entitled "Selling
Shareholders" (which appears on page 10 of the Prospectus), the following
information is provided with respect to the beneficial owners of the Common
Stock:
Amount of Shares Amount of
Beneficially Owned Shares to be
Name of Selling Shareholder(s) as of August 11, 1998 Offered for Sale
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Societal Ventures Corporation(1) 27,900 27,900
(1) Societal Ventures Corporation renders consulting services to a subsidiary
of GPC.
Except for the purchase of the shares of Common Stock and the information
disclosed in the footnote above, the Selling Shareholder has not had a material
relationship with the Company or any of its affiliates within the past three
years.
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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 August 13, 1998.
