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                                                                     Exhibit 4.1

NUMBER                                       SHARES

COMMON SHARES                                COMMON SHARES

THIS CERTIFICATE IS TRANSFERABLE IN          CUSIP G7127P 10 0
NEW YORK, NY AND RIDGEFIELD PARK, N.J.       SEE REVERSE FOR CERTAIN DEFINITIONS

                      PLATINUM UNDERWRITERS HOLDINGS, LTD.
                       ORGANIZED UNDER THE LAWS OF BERMUDA

                               This Certifies that


                           is the registered holder of


            FULLY PAID AND NON-ASSESSABLE SHARES OF THE PER VALUE OF
                          $0.01 EACH OF THE CAPITAL OF

                            COMMON SHARE CERTIFICATE


DATED
/s/ Jerome T. Fadden                                  /s/  Steven H. Newman
    President                                              Chairman


COUNTERSIGNED AND REGISTERED:
        MELLON INVESTOR SERVICES LLC
                               TRANSFER AGENT
                               AND REGISTRAR,

BY
                         AUTHORIZED SIGNATURE
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                      PLATINUM UNDERWRITERS HOLDINGS, LTD.

         The following abbreviations, when used in the inscription on the face
of this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

         TEN COM - as tenants in common
         TEN ENT - as tenants by the entireties
         JT TEN - as joint tenants with right of
                  survivorship and not as
                  tenants in common

         UNIF GIFT MIN ACT-.........Custodian.............
                             (Cust)            (Minor)
                           under Uniform Gifts to Minors
                           Act............
                                (State)


     Additional abbreviations may also be used though not in the above list.


         FOR VALUE RECEIVED, ___________ HEREBY SELL, ASSIGN AND TRANSFER UNTO


PLEASE INSERT SOCIAL SECURITY OR OTHER
   IDENTIFYING NUMBER OF ASSIGNEE
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________________________________________________________________________________
 (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________ SHARES
REPRESENTED BY THE WITHIN CERTIFICATE, AND DO HEREBY IRREVOCABLY CONSTITUTE AND
APPOINT _______________________________________________ ATTORNEY TO TRANSFER THE
SAID SHARES ON THE BOOKS OF THE WIHIN NAMED COMPANY WITH FULL POWER OF
SUBSTITUTION IN THE PREMISES
DATED  ______________________


                         _____________________________________________________
                NOTICE:  THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH
                         THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE
                         IN EVERY PARTICULAR WITHOUT ALTERATION OR ENLARGEMENT
                         OR ANY CHANGE WHATEVER.


Signature(s) Guaranteed:



---------------------------------------------------
THE SIGNATURE(S) MUST BE SIGNED BY AN ELIGIBLE
GUARANTOR INSTITUTION (BANKS, STOCKBROKERS,
SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS
WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE
MEDALLION PROGRAM). PURSUANT TO S.E.C. RULE 17A-15.