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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (No. 333-162785) of Cowen Group, Inc. (formerly LexingtonPark Parent Corp.) of our report dated March 25, 2010 relating to the financial statements, which appears in this Form 10-K.

/s/ PRICEWATERHOUSECOOPERS LLP 
New York, New York
March 25, 2010

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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM