Prospectus Supplement filed under Rule 424(b)(3) Registration No. 333-45569 Prospectus Supplement The Prospectus dated February 4, 1998 relating to the offer for resale of up to $250,000,000 aggregate principal amount of The Interpublic Group of Companies, Inc.'s 1.80% Convertible Subordinated Notes due September 16, 2004 is hereby supplemented to include the following information in the "Selling Securityholders" table in the Prospectus Supplement dated February 25, 1998: Principal Amount of Registered Selling Holders Notes Morgan Stanley Dean Witter(1)................ $9,355,000 Total of Above............................... $9,355,000 - ------------------ 1 Morgan Stanley & Co. Incorporated, an affiliate of Morgan Stanley Dean Witter, was an Initial Purchaser of the 1.80% Convertible Subordinated Notes due September 16, 2004 when such Notes were originally sold in a private placement. The "Selling Securityholders" table in the Prospectus, as supplemented, is amended so that the principal amount of registered Notes held by McMahan Securities Company, L.P. is reduced from $5,325,000 to $500,000. This Prospectus Supplement is dated May 11, 1998.