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                                                                    EXHIBIT 99.4


                        CERTIFICATION OF PERIODIC REPORT
                        --------------------------------



I, Dara Khosrowshahi, Executive Vice President and Chief Financial Officer of
USA Interactive (the "Company"), certify, pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, that:

(1)      the Quarterly Report on Form 10-Q of the Company for the quarterly
         period ended June 30, 2002 (the "Report") which this statement
         accompanies fully complies with the requirements of Section 13(a) or
         15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d));
         and

(2)      the information contained in the Report fairly presents, in all
         material respects, the financial condition and results of operations of
         the Company.



Dated:  August 14, 2002



                                           /s/ Dara Khosrowshahi
                                           -------------------------------------
                                            Dara Khosrowshahi
                                            Executive Vice President and
                                            Chief Financial Officer