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                                                                      EXHIBIT 99

                             QUARTERLY CERTIFICATION
            PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (subsections (a) and
(b) of Section 1350, Chapter 63 of Title 18, United States Code), each of the
undersigned officers of The Interpublic Group of Companies, Inc., a Delaware
corporation (the "Company"), does hereby certify, to such officer's knowledge,
that:

The quarterly report on Form 10-Q for the quarter ended March 31, 2003 of the
Company fully complies with the requirements of section 13(a) or 15(d) of the
Securities Exchange Act of 1934 and information contained in the Form 10-Q
fairly presents, in all material respects, the financial condition and results
of operations of the Company.


      Dated:   May 15, 2003                        /s/ David A. Bell
                                                   ---------------------------
                                                   David A. Bell
                                                   Chief Executive Officer


      Dated:   May 15, 2003                        /s/ Sean F. Orr
                                                   ---------------------------
                                                   Sean F. Orr
                                                   Chief Financial Officer


      The foregoing certification is being furnished solely pursuant to Section
906 of the Sarbanes-Oxley Act of 2002 (subsections (a) and (b) of Section 1350,
Chapter 63 of Title 18, United States Code) and is not being filed as part of
the Form 10-Q or as a separate disclosure document. A signed original of this
written statement required by Section 906 has been provided to the Company and
will be retained by the Company and furnished to the Securities and Exchange
Commission or its staff upon request.