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 April 20, 1998 the closing price of the
Common Stock as reported on the New York Stock Exchange was $47.3125 per share.
The Common Stock is traded under the symbol "OMC."
None of the Selling Shareholders owns in excess of 1% of the Common Stock
of the Company and since the Selling Shareholders 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 each 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 April 20, 1998(1) Offered for Sale
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Societal Ventures Corporation(2) 98,908 18,908
3119025 Canada Inc.(3)(4) 45,024 35,000
3423611 Canada Inc.(3) 420,358 300,000
1067913 Ontario Limited(3)(5) 70,060 17,500
(1) Includes (a) 80,000 shares of Common Stock which Societal Ventures
Corporation has the right to acquire upon the exchange of 80,000
Exchangeable Shares, (b) 10,024 shares of Common Stock which 3119025 Canada
Inc. has the right to acquire upon the exchange of 10,024 Exchangeable
Shares, (c) 120,358 shares of Common Stock which 3423611 Canada Inc. has
the right to acquire upon the exchange of 120,358 Exchangeaable Shares and
(d) 52,560 shares of Common Stock which 1067913 Ontario Limited has the
right to acquire upon the exchange of 52,560 Exchangeable Shares.
(2) Societal Ventures Corporation renders consulting services to a subsidiary
of GPC.
(3) The controlling shareholder is an officer and/or director of GPC and a
subsidiary of GPC.
(4) Patrick Ross, controlling shareholder and director, directly owns 25,036
Exchangeable Shares.
(5) James Crossland, controlling shareholder and director, indirectly owns 290
shares of Common Stock.
Except for the purchase of the shares of Common Stock, their current
holdings of Exchangeable Shares and the information disclosed in the footnotes
above, none of the Selling Shareholders has 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 April 22, 1998.
