Cowen 10-Q 2007 Q3 Quarterly report

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Exhibit 32

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 Quarterly Report of Cowen Group, Inc. (the "Company") on Form 10-Q for the quarter ended September 30, 2007, as filed with the Securities and Exchange Commission on the date hereof (the "Report"), each of the undersigned officers of the Company certifies, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to such officer's knowledge:

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 results of operations of the Company.

Date: November 13, 2007

/s/  KIM S. FENNEBRESQUE      Kim S. Fennebresque
Chairman, Chief Executive Officer and
President (principal executive officer)

/s/  THOMAS K. CONNER      Thomas K. Conner
Chief Financial Officer and Treasurer
(principal financial officer and principal
accounting officer)

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Exhibit 32

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