EX-32.1 4 a2188892zex-32_1.htm EXHIBIT 32.1
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Exhibit 32.1

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        I, Barry Diller, certify, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, that, to my knowledge:

    (1)
    the Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2008 of IAC/InterActiveCorp (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 IAC/InterActiveCorp.

Dated: November 10, 2008   /s/ BARRY DILLER

Barry Diller
Chairman and Chief Executive Officer



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CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002