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 Selling Holders of Registered Notes --------------- ------------------- Bancroft Convertible Fund, Inc........................ $1,000,000.00 - ------------------------------------------------------ ------------- Ellsworth Convertible Growth and Income Fund, Inc..... $1,000,000.00 - ------------------------------------------------------ ------------- Total of Above........................................ $2,000,000.00 ============= This Prospectus Supplement is dated June 4, 1999.