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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1. Name and Address of Reporting Person * SLATTERY JAMES P   2. Issuer Name and Ticker or Trading Symbol PLATINUM UNDERWRITERS HOLDINGS LTD [PTP] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O PLATINUM UNDERWRITERS HOLDINGS, LTD., 69 PITTS BAY ROAD, 3RD FLOOR 3. Date of Earliest Transaction (Month/Day/Year) 04/27/2011 (Street) PEMBROKE, D0 HM 08 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 04/27/2011   M   1,362 A $ 0 3,696 D

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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

Share units

(1)

04/27/2011

M

1,362

(2)

(2)

Common Shares (2)

1,362

$ 0

0

D

Share units

(1)

04/27/2011

A

1,341

(3)

(3)

Common Shares (3)

1,341

$ 0

1,341

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
SLATTERY JAMES P C/O PLATINUM UNDERWRITERS HOLDINGS, LTD. 69 PITTS BAY ROAD, 3RD FLOOR PEMBROKE, D0 HM 08	X

Signatures

Christina M. Parker, Attorney-in-fact		04/27/2011
**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)	1-for-1
(2)	These share units were awarded on April 29, 2010 pursuant to the Company's 2010 Share Incentive Plan. On the date of the Company's 2011 Annual General Meeting of Shareholders, the Company issued to the reporting person one Common Share of the Company for each of the share units awarded to the reporting person.
(3)	These shares were awarded on April 27, 2011 pursuant to the Company's 2010 Share Incentive Plan. On the earlier to occur of the first anniversary of the date of the grant or the date of the Company's next Annual General Meeting of Shareholders, the Company will issue to the reporting person one Common Share of the Company for each of the share units awarded to the reporting person, subject to the reporting person's continued service with the Company through the applicable vesting date.

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