Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
LABRANCHE & CO INC
  2. Issuer Name and Ticker or Trading Symbol
COWEN GROUP, INC. [COWN]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
_____ Officer (give title below) __X__ Other (specify below)
See Footnotes (1) and (2)
(Last)
(First)
(Middle)
599 LEXINGTON AVENUE
3. Date of Earliest Transaction (Month/Day/Year)
06/28/2011
(Street)

NEW YORK, NY 10022
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Class A common stock, par value $0.01 per share 06/28/2011   J(1)(2)   0 D (1) (2) 0 I See footnote (1) (2)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
LABRANCHE & CO INC
599 LEXINGTON AVENUE
NEW YORK, NY 10022
      See Footnotes (1) and (2)

Signatures

 See Exhibit 99.1   06/29/2011
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Beneficial ownership of shares of Class A common stock, par value $0.01 per share, of Cowen Group, Inc. ("Parent Common Stock") referred to herein was reported in the Initial Statement of Beneficial Ownership of Securities on Form 3 filed with the Securities and Exchange Commission on February 25, 2011 because Cowen Structured Holdings LLC (f/k/a LaBranche & Co Inc. "LaBranche") may have been deemed to have had beneficial ownership of such shares as a result of the granting of an irrevocable proxy by RCG Holdings LLC ("RCG") pursuant to that certain Voting Agreement, dated as of February 16, 2011, by and between LaBranche and RCG (the "Voting Agreement"). On June 28, 2011, the merger of Louisiana Merger Sub, Inc., a direct, wholly-owned subsidiary of Cowen Group, Inc. ("Merger Sub"), with and into LaBranche was completed and the Voting Agreement and the irrevocable proxy contained therein terminated by its terms.
(2) Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that LaBranche is or was, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owner of any shares of Parent Common Stock referred to herein, and such beneficial ownership is expressly disclaimed. LaBranche does not have any pecuniary interest in the Parent Common Stock and therefore does not have beneficial ownership of any shares of Parent Common Stock within the meaning of Rule 16a-1(a)(2) of the Exchange Act.

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