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Exhibit 99.2

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

        In connection with the Annual Report of Cephalon, Inc. (the "Company") on Form 10-K for the fiscal year ended December 31, 2003 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, J. Kevin Buchi, Sr. Vice President and Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, based on my knowledge, that:

        (1)  The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

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

/s/  J. KEVIN BUCHI

J. Kevin Buchi
Sr. Vice President and Chief Financial Officer

March 31, 2003

*

A signed original of this written statement required by Section 906 has been provided to Cephalon, Inc. and will be retained by Cephalon, Inc. and furnished to the Securities and Exchange Commission or its staff upon request.

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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