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 * BYRNE MARK JAMES   2. Issuer Name and Ticker or Trading Symbol Flagstone Reinsurance Holdings Ltd [FSR] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director __X__ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Chairman (Last) (First) (Middle) FLAGSTONE REINSURANCE HOLDINGS LTD., CRAWFORD HOUSE, 23 CHURCH STREET 3. Date of Earliest Transaction (Month/Day/Year) 03/22/2010 (Street) HAMILTON, D0 HM11 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 Common Shares 03/22/2010   J(1)   131,115 (1) A $ 0 2,849,719 (1) I By Haverford (Bermuda) Ltd. (1) Common Shares               7,155,156 I By IAL FSR Limited (2) Common Shares               50,000 I By Rebecca Byrne (3)

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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
BYRNE MARK JAMES FLAGSTONE REINSURANCE HOLDINGS LTD. CRAWFORD HOUSE, 23 CHURCH STREET HAMILTON, D0 HM11	X	X	Chairman

Signatures

/s/ Mark James Byrne		04/06/2010
**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)	On March 22, 2010, Haverford Capital Partners (Cayman) Limited ("HCP") distributed 141,509 common shares of the issuer to Haverford Investment Holdings (Cayman) Limited, a wholly-owned subsidiary of Haverford (Bermuda) Ltd. ("Haverford"). The reporting person may be deemed to have investment or voting control over Haverford. Haverford holds the shares through a trust for the benefit of others, and the reporting person therefore disclaims beneficial ownership of these shares. 131,115 common shares acquired represent the indirect proportionate interest of the reporting person in the 141,509 common shares of the issuer acquired by Haverford. 2,849,719 common shares represent the indirect proportionate interest of the reporting person in the 3,075,618 common shares of the issuer held by Haverford.
(2)	These common shares are held by IAL FSR Limited for the benefit of a company owned by a trust for which the reporting person serves as settlor. The reporting person disclaims beneficial ownership of these shares.
(3)	These common shares represent shares purchased in connection with the initial public offering of the issuer and are owned by Rebecca Byrne, the wife of the reporting person. The reporting person disclaims beneficial ownership of the common shares held by his wife.

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