UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

Current Report

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): December 8, 2011

COWEN GROUP, INC.

(Exact Name of Registrant as Specified in Charter)

599 Lexington Avenue

New York, NY 10022

(Address of Principal Executive Offices and Zip Code)

Registrant’s telephone number, including area code: (212) 845-7900

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 5.02.                                          Departures of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On December 8, 2011, the Board of Directors (the “Board”) of Cowen Group, Inc. (the “Company”) appointed Thomas W. Strauss and Jeffrey M. Solomon to serve on the Company’s Board, effectively immediately.  On December 12, 2011, the Company issued a press release announcing the appointments of Messrs. Strauss and Solomon.  Mr. Strauss is the President and Chief Executive Officer of Ramius and Mr. Solomon is the Chief Executive Officer of Cowen and Company.  A copy of the press release is attached hereto as Exhibit 99.1.

Item 9.01. Financial Statements and Exhibits.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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