Document:

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                                                                  Exhibit 4.6

                                FORM OF NOTE

            The Notes and the Trustee's Certificate of Authentication to be
endorsed thereon are to be substantially in the following forms:

            [IF THE NOTE IS A GLOBAL NOTE, INSERT - This Note is a Global Note
      within the meaning of the Indenture hereinafter referred to and is
      registered in the name of the Depository or a nominee of the Depository.
      This Note is exchangeable for Notes registered in the name of a person
      other than the Depository or its nominee only in the limited circumstances
      described in the Indenture, and no transfer of this Note (other than a
      transfer of this Note as a whole by the Depository to a nominee of the
      Depository or by a nominee of the Depository to the Depository or another
      nominee of the Depository) may be registered except in limited
      circumstances.

            Unless this Note is presented by an authorized representative of The
      Depository Trust Company (55 Water Street, New York, New York) to the
      issuer or its agent for registration of transfer, exchange or payment, and
      any Note issued is registered in the name of Cede & Co. or such other name
      as requested by an authorized representative of The Depository Trust
      Company and any payment hereon is made to Cede & Co., ANY TRANSFER,
      PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY A PERSON IS WRONGFUL
      since the registered owner hereof, Cede & Co. , has an interest herein.]

No.

CUSIP No.                                                $_________________

                                        1

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                       PLATINUM UNDERWRITERS FINANCE, INC.
                       *% SENIOR GUARANTEED NOTE DUE 2007

            PLATINUM UNDERWRITERS FINANCE, INC. , a Delaware corporation (the
"Company", which term includes any successor corporation under the Indenture
hereinafter referred to) , for value received, hereby promises to pay to
___________________, the principal sum of ______ dollars ($_____________) on
{*], 2007 (such date is hereinafter referred to as the "Stated Maturity Date"),
and to pay interest on said principal sum from *, 2002, or from the most recent
interest payment date initially at the rate of *% per annum (the "Interest
Rate") up to, but excluding, the Reset Date; provided, however, that in the
event a Last Failed Remarketing occurs, this Note shall continue to bear
interest at the Interest Rate until the principal of the Notes is paid or made
available for payment. In the event the Notes are successfully remarketed
pursuant to the Purchase Contract and Remarketing Agreement, this Note shall
bear interest at the Reset Rate, from and including the Reset Date to the date
on which principal hereof is paid or made available for payment; PROVIDED that
any principal and installment of interest which is overdue shall bear interest
(to the extent that payment of such interest is enforceable under applicable
law) at the Interest Rate up to but excluding the Reset Date, if any, and
thereafter at the Reset Rate, from the dates such amounts are due until they are
paid or made available for payment, and such interest shall be payable on
demand. Interest on this Note initially shall be payable quarterly in arrears on
[*, *, *, and *] of each year (each, an "Interest Payment Date"), commencing *,
2002 through and including *, 2005, and then semi-annually in arrears on the
Interest Payment Dates of * and * of each year, commencing on *, 2006 until the
principal hereof is paid or made available for payment. The amount of interest
payable for any period on any Interest Payment Date shall be computed on the
basis of a 360-day year consisting of twelve 30-day months. Except as provided
in the following sentence, the amount of interest payable for any period shorter
than a full quarterly or semi-annual period, as applicable, for which interest
is computed will be computed on the basis of the actual number of days elapsed
in such a 90-day or 180-day period, as applicable. In the event that any date on
which interest is payable on this Note is not a Business Day, then payment of
interest payable on such date will be made on the next succeeding day that is a
Business Day (and without any interest or other payment in respect of any such
delay), except that, if such Business Day is in the next succeeding calendar
year, such payment shall be made on the immediately preceding Business Day, in
each case with the same force and effect as if made on such date. The interest
installment so payable, and punctually paid or duly provided for, on any
Interest Payment Date will, as provided in the Indenture, be paid to the person
in whose name this Note is registered at the close of business on the regular
record date for such interest installment, which as long as any Notes are
represented by a Global Note shall be the close of business on the Business Day
next preceding such Interest Payment Date; PROVIDED, HOWEVER, if pursuant to the
terms of the Indenture the Notes are no longer represented by a Global Note, the
Company may select such regular record date for such interest installment which
shall be more than one Business Day but less than 60 Business Days prior to such
Interest Payment Date. Any such interest installment not punctually paid or duly
provided for

                                        2

<PAGE>

shall forthwith cease to be payable to the registered Holders on such regular
record date and may be paid to the Person in whose name this Note is registered
at the close of business on a special record date to be fixed by the Trustee for
the payment of such defaulted interest, notice whereof shall be given to the
registered Holders of this series of Notes not less than 10 days prior to such
special record date, or may be paid at any time in any other lawful manner not
inconsistent with the requirements of any securities exchange on which the Notes
may be listed, and upon such notice as may be required by such exchange all as
more fully provided in the Indenture. The principal of and the interest on this
Note shall be payable at the office or agency of the Company maintained for that
purpose in any coin or currency of the United States of America that at the time
of payment is legal tender for payment of public and private debts; PROVIDED,
HOWEVER, that payment of interest may be made at the option of the Company by
check mailed to the registered Holder at such address as shall appear in the
Register or by wire transfer to an account appropriately designated by the
Holder entitled thereto.

            Reference is hereby made to the further provisions of this Note set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if fully set forth at this place.

            Unless the certificate of authorization hereon has been executed by
the Trustee referred to on the reverse hereof by manual signature, this Note and
the Guarantee endorsed herein shall not be entitled to any benefit under the
Indenture or be valid or obligatory for any purpose.

                                        3

<PAGE>

            IN WITNESS WHEREOF, the Company has caused this instrument to be
executed under its corporate seal.

Dated:

                                                 PLATINUM UNDERWRITERS
                                                 FINANCE, INC.

                                                 By:
                                                    ----------------------------
                                                    Name:
                                                    Title:

[SEAL]

Attest:

-------------------

                                  CERTIFICATE OF AUTHENTICATION

            This is one of the Notes of the series designated herein referred to
in the within-mentioned Indenture.

                                                   JPMORGAN CHASE BANK,
                                                   as Trustee

                                                   By:
                                                      --------------------------
                                                       Authorized Officer

                                        4

<PAGE>

                            (FORM OF REVERSE OF NOTE)

            This Note is one of a duly authorized series of the Senior
Guaranteed Notes of the Company (herein sometimes referred to as the
"Securities"), specified in the Indenture hereinafter referred to, all issued or
to be issued in one or more series under and pursuant to an Indenture dated as
of *, 2002 (the "Base Indenture"), duly executed and delivered among the
Company, Platinum Underwriters Holdings, Ltd. , as guarantor (herein called the
"Guarantor") and JPMorgan Chase Bank, as Trustee (the "Trustee") (such Base
Indenture as supplemented by the First Supplemental Indenture, dated *, 2002,
the "Indenture"), to which Indenture and all indentures supplemental thereto
reference is hereby made for a description of the rights, limitations of rights,
obligations, duties and immunities thereunder of the Trustee, the Company and
the Holders of the Securities. By the terms of the Indenture, the Securities are
issuable in series that may vary as to amount, date of maturity, rate of
interest and in other respects as provided in the Indenture. This series of
Securities is limited in aggregate principal amount as specified in said First
Supplemental Indenture.

            The Securities of this series were initially issued as components of
the Company's equity units that are in the form of Normal Units, each such
Normal Unit initially consisting of (a) a stock purchase contract (each, a
"Purchase Contract") under which (i) the holder will agree to purchase from the
Company on *, 2005, a specified number of newly issued common shares, par value
$0.01 per share, of the Company and (ii) the Company will pay to the holder
quarterly contract adjustment payments and (b) a 1/40, or 2.5%, ownership
interest in a Security of this series of $1,000 principal amount. In accordance
with the terms of the Purchase Contract Agreement, on their initial issuance the
Securities of this series were pledged by the Purchase Contract Agent, on behalf
of the holders of the Normal Units, to State Street Bank and Trust Company, as
collateral agent, custodial agent and securities intermediary (the "Collateral
Agent"), pursuant to the Pledge Agreement, dated as of *, 2002 (the "Pledge
Agreement"), among the Company, the Purchase Contract Agent and the Collateral
Agent, to secure such holders' obligations to purchase common shares of the
Company under the Purchase Contracts. Pursuant to the Remarketing Agreement, the
Remarketing Agent shall use its commercially reasonable best efforts to remarket
the Securities of this series that are included in Normal Units at a specified
price on certain dates, all as specified in Section 5.4(b) of the Purchase
Contract Agreement. Pursuant to Section 4.5(d) of the Pledge Agreement, Holders
of all other Securities of this series may elect to have such Securities
remarketed in accordance with the procedures set forth therein.

            If a Tax Event (as herein defined) shall occur and be continuing,
the Company may, at its option, redeem the Notes then Outstanding in whole (but
not in part) at any time ("Tax Event Redemption") at the Redemption Price (as
herein defined). If such Tax Event Redemption occurs prior to a successful
remarketing pursuant to Section 5.4 of the Purchase Contract Agreement, the
Redemption Price payable with respect to the Notes pledged to the Collateral
Agent under the Pledge Agreement will be paid to the

                                        5
<PAGE>

Collateral Agent on the Tax Event Redemption Date on or prior to 12:00 p.m. ,
New York City time, by wire transfer in immediately available funds at such
place and at such account as may be designated by the Collateral Agent in
exchange for the Notes pledged to the Collateral Agent; in such event, the
Collateral Agent shall apply such Redemption Price pursuant to the terms of the
Purchase Contract Agreement and the Pledge Agreement.

            Notice of any redemption will be mailed at least 30 days but not
more than 60 days before the date of redemption (the "Tax Event Redemption
Date") to each registered Holder of Notes of this Series to be redeemed at its
registered address as more fully provided in the Indenture. Unless the Company
defaults in payment of the Redemption Price, on and after the Tax Event
Redemption Date interest shall cease to accrue on such Notes of this Series.

            "Quotation Agent" means Goldman, Sachs & Co. or any of its
successors or any other primary U.S. government securities dealer in The City of
New York selected by the Company.

            "Redemption Price" means, for each Note, the product of (i) the
principal amount of such Note and (ii) a fraction whose numerator is the
applicable Treasury Portfolio Purchase Price (as herein defined) and whose
denominator is the applicable Tax Event Redemption Principal Amount (as herein
defined).

            "Tax Event" means the receipt by the Company of an opinion of a
nationally recognized tax counsel experienced such matters, to the effect that
there is more than an insubstantial risk that interest payable by the Company on
the Notes on the next Interest Payment Date will not be deductible, in whole or
in part, by the Company for United States federal income tax purposes as a
result of (a) any amendment to, or change (including any announced proposed
change) in, the laws (or any regulations there under) of the United States or
any political subdivision or taxing authority thereof or therein affecting
taxation (other than any such amendment, change or announced proposed change to
the so-called "earnings stripping" provisions of Section 163(j) of the Internal
Revenue Code, which limit the ability of U.S. corporations to deduct interest on
certain debt owed to or guaranteed by related foreign persons), (b) any
amendment to or change in an official interpretation or application of such laws
or regulations by any legislative body, court, governmental agency or regulatory
authority or (c) any official interpretation, pronouncement or application that
provides for a position with respect to such laws or regulations that differs
from the generally accepted position on *, 2002, which amendment, change or
proposed change is effective or which interpretation or pronouncement is
announced on or after *, 2002.

            "Tax Event Redemption Principal Amount" means (i) in the case of a
Tax Event Redemption Date occurring prior to a successful remarketing of the
Notes pursuant to the Purchase Contract Agreement, the aggregate principal
amount of Notes included in Normal Units on such date, and (ii) in the case of a
Tax Event Redemption Date

                                       6
<PAGE>

occurring after a successful remarketing of the Notes pursuant to the Purchase
Contract Agreement, the aggregate principal amount of the Notes.

            "Treasury Portfolio Purchase Price" means the lowest aggregate price
quoted by a primary U.S. government securities dealer in New York City to the
Quotation Agent on the third Business Day immediately preceding the Tax Event
Redemption Date for the purchase of the Treasury Portfolio for settlement on the
Tax Event Redemption Date.

            "Treasury Portfolio" means: (i) if a Tax Event Redemption occurs
prior to a successful remarketing of the Notes pursuant to the provisions of the
Purchase Contract Agreement, a portfolio (A) of zero-coupon U. S. Treasury
securities consisting of principal or interest strips of U.S. Treasury
securities that mature on or prior to *, 2005 in an aggregate amount equal to
the applicable Tax Event Redemption Principal Amount and (B) with respect to
each scheduled Interest Payment Date on the Notes that occurs after the Tax
Event Redemption Date and on or before *, 2005, interest or principal strips of
U.S. Treasury securities that mature on or prior to such Interest Payment Date
in an aggregate amount equal to the aggregate interest payment that would be due
on the applicable Tax Event Redemption Principal Amount on such date if the
interest rate of the Notes were not reset on the Reset Date, and (ii) solely for
purposes of determining the Treasury Portfolio Purchase Price in the case of a
Tax Event Redemption Date occurring after a successful remarketing of the Notes
pursuant to the Purchase Contract Agreement or *, 2005, a portfolio (A) of
zero-coupon U.S. Treasury securities consisting of principal or interest strips
of U.S. Treasury securities that mature on or prior to the Maturity Date in an
aggregate amount equal to the applicable Tax Event Redemption Principal Amount
and (B) with respect to each scheduled Interest Payment Date on the Notes that
occurs after the Tax Event Redemption Date and on or before the Maturity Date,
interest or principal strips of U.S. Treasury securities that mature on or prior
to such Interest Payment Date in an aggregate amount equal to the aggregate
interest payment that would be due on the applicable Tax Event Redemption
Principal Amount of the Notes Outstanding on the Tax Event Redemption Date.

            The Notes do not have the benefit of any sinking fund obligation.

            In case an Event of Default, as defined in the Indenture, shall have
occurred and be continuing, the principal of all of the Notes may be declared,
and upon such declaration shall become, due and payable, in the manner, with the
effect and subject to the conditions provided in the Indenture.

            The Indenture permits, with certain exceptions as therein provided,
the amendment thereof and the modification of the rights and obligations of the
Company and the Guarantor and the rights of the Holders of the Notes under the
Indenture at any time by the Company, the Guarantor and the Trustee with the
consent of the majority of the Holders in principal amount of the Notes at the
time Outstanding. The Indenture also contains provisions permitting the Holders
of specified percentages in aggregate principal amount of the Notes at the time
Outstanding, on behalf of the Holders of all the Notes, to waive compliance by
the Company or the Guarantor, or both, with certain

                                       7
<PAGE>

provisions of the Indenture and certain past defaults under the Indenture and
their consequences. Any such consent or waiver by the Holder of this Note shall
be conclusive and binding upon such Holder and upon all future Holders of this
Note and of any Note issued upon the registration of transfer hereof or in
exchange hereof or in lieu hereof, whether or not notation of such consent or
waiver is made upon this Note.

            No reference herein to the Indenture and no provision of this Note
or of the Indenture shall alter or impair the obligation of the Company, which
is absolute and unconditional, to pay the principal of and premium, if any, and
interest on this Note at the times, place and rate, and in the coin or currency
herein prescribed.

            As provided in the Indenture and subject to certain limitations
therein set forth, this Note is transferable by the registered Holder hereof on
the Register of the Company, upon surrender of this Note for registration of
transfer at the office or agency of the Trustee in the City of New York and
State of New York accompanied by a written instrument or instruments of transfer
in form satisfactory to the Company or the Trustee duly executed by the
registered Holder hereof or his attorney duly authorized in writing, and
thereupon one or more new Notes of authorized denominations and for the same
aggregate principal amount and series will be issued to the designated
transferee or transferees. No service charge will be made for any such transfer,
but the Company may require payment of a sum sufficient to cover any tax,
assessment or other governmental charge payable in relation thereto.

            Prior to due presentment for registration of transfer of this Note,
the Company, the Guarantor, the Trustee, any paying agent and the Registrar may
deem and treat the registered holder hereof as the absolute owner hereof
(whether or not this Note shall be overdue and notwithstanding any notice of
ownership or writing hereon made by anyone other than the Registrar) for the
purpose of receiving payment of or on account of the principal hereof and
premium, if any, and interest due hereon and for all other purposes, and neither
the Company, the Guarantor nor the Trustee nor any paying agent nor any
Registrar shall be affected by any notice to the contrary.

            No recourse shall be had for the payment of the principal of or the
interest on this Note, or for any claim based hereon, or otherwise in respect
hereof, or based on or in respect of the Indenture, against any incorporator,
shareholder, officer or director, past, present or future, as such, of the
Company or the Guarantor or of any predecessor or successor corporations,
whether by virtue of any constitution, statute or rule of law, or by the
enforcement of any assessment or penalty or otherwise, all such liability being,
by the acceptance hereof and as part of the consideration for the issuance
hereof, expressly waived and released.

            The Indenture imposes certain limitations on the ability of the
Company and the Guarantor to, among other things, merge or consolidate with any
other Person or sell, assign, transfer, lease or convey all or substantially all
of its properties and assets. All such covenants and limitations are subject to
a number of important qualifications and

                                       8

<PAGE>

exceptions. The Company and Guarantor must report periodically to the Trustee on
compliance with the covenants in the Indenture.

            The Notes of this series are issuable only in registered form
without coupons, in denominations of $1000 and any integral multiple thereof
except that an interest in a Note held as part of a Normal Unit represents an
ownership interest of 1/40th, or 2.5%, of a Note in aggregate principal amount
of $1000 and will therefore correspond to the stated amount of $25 per Normal
Unit. As provided in the Indenture and subject to certain limitations therein
set forth, Notes of this series so issued are exchangeable for a like aggregate
principal amount of Notes of this series of a different authorized denomination,
as requested by the Holder surrendering the same.

            [IF NOTE IS A GLOBAL NOTE, INSERT - This Note is a Global Note and
is subject to the provisions of the Indenture relating to Global Notes,
including the limitations in Section 305 of the Base Indenture on transfers and
exchanges of Global Notes.]

            All terms used in this Note that are defined in the Indenture shall
have the meanings assigned to them in the Indenture.

            This Note and the Guarantee endorsed herein shall be governed by and
construed in accordance with the laws of the State of New York, without giving
effect to conflicts of laws principles thereof.

                                      9
<PAGE>

                                   GUARANTEE

      For value received, Platinum Underwriters Holdings, Ltd., a corporation
organized under the laws of Bermuda (herein called the "Guarantor", which term
includes any successor under the Indenture referred to in the Note upon which
this Guarantee is endorsed), hereby absolutely, fully and unconditionally and
irrevocably guarantees to the Holder of the Note upon which this Guarantee is
endorsed, and to the Trustee on behalf of such Holder, (a) the due and punctual
payment of the principal of and interest (and, if applicable, the Redemption
Price) on such Note, whether at the Stated Maturity or by acceleration, call for
redemption or otherwise, (b) the due and punctual payment of interest on overdue
principal of and interest on such Note, if any, if lawful, and (c) the due and
punctual payment of any and all other payments due to the Holder, all in
accordance with the terms of such Note and of the Indenture. In case of the
failure of the Company punctually to make any such payment of principal,
premium, if any, or interest, if any, the Guarantor hereby agrees to cause any
such payment to be made punctually when and as the same shall become due and
payable, whether at the Stated Maturity or by declaration of acceleration, call
for redemption or otherwise, and as if such payment were made by the Company.

      The Guarantor hereby agrees that its obligations hereunder are a guaranty
of payment and not a guaranty of collection or performance and shall be
unconditional and absolute, irrespective of the validity, regularity or
enforceability of such Note or the Indenture or any limitation of the Company
thereunder or any limitation on the method or terms of payment thereunder which
may now or hereafter be caused or imposed in any manner whatsoever, the absence
of any action to enforce the same, any waiver or consent by the Holder of such
Note or by the Trustee with respect to any provisions thereof or of the
Indenture, the obtaining of any judgment against the Company or any action to
enforce the same or any other circumstance which might otherwise constitute a
legal or equitable discharge or defense of a guarantor. The Guarantor hereby
waives the benefits of division and discussion, diligence, presentment, demand
of payment, filing of claims with a court in the event of insolvency or
bankruptcy of the Company, any right to require a proceeding first against the
Company, protest or notice with respect to such Note or the indebtedness
evidenced thereby and all demands whatsoever, and covenants that this Guarantee
will not be discharged except by complete performance of the obligations
contained in such Note and in this Guarantee. Without limiting the generality of
the foregoing, the Guarantor hereby agrees that the obligations of the Guarantor
hereunder shall not be released, affected or impaired by assignment or transfer
in whole or in part of the Note whether or not made without notice to or the
consent of the Guarantor and shall not be subject to any reduction, limitation,
impairment or termination for any reason, including any claim of waiver,
release, surrender, alteration or compromise, and shall not be subject to any
defense of, including, but not limited to, setoff, counterclaim, recoupment or
termination whatsoever, and that such obligations shall not be released,
affected or impaired regardless of whether or not any Holder, including the
Holder of the Note, or anyone on behalf of any such Holder shall have instituted
any suit, action or proceeding or

                                       10
<PAGE>

exhausted its remedies or taken any steps to enforce any rights against the
Company or any other person to compel any such performance or observance or to
collect all or part of any such amount, either pursuant to the provisions of the
Indenture or the Note or at law or in equity, and regardless of any other
condition or contingency, or by reason of the invalidity, illegality or
unenforceability of the Note or the Indenture or otherwise and that such
obligations shall not be discharged or impaired or otherwise affected by the
failure of the Trustee or any Holder of such Note to assert any claim or demand
or to enforce any remedy under the Indenture or such Note, any other guarantee
or any other agreement, by any waiver, amendment, indulgence or modification
(whether material or otherwise) of any provision of any thereof, by any default,
failure or delay, willful or otherwise, in the performance of any obligations
under the Indenture, the Note or this Guarantee, or by the voluntary or
involuntary liquidation, sale or other disposition of all or substantially all
of the assets of the Company or the Guarantor, or any receivership, insolvency,
bankruptcy, reorganization, or other similar proceedings, affecting the Company
or any of its assets, or the release of any property from the lien and security
interest created by the Indenture or the Note or of any other security for the
Note, or the release or discharge of the Company or the Guarantor from the
performance or observance of any agreement, covenant, term or condition
contained in the Indenture or the Note by operation of law, or the merger or
consolidation of the Company or the Guarantor, or any other cause, whether
similar or dissimilar to the foregoing, or by any other act or omission that may
or might in any manner or to any extent vary the risk or obligations of the
Guarantor or that would otherwise operate as a discharge of a surety or
guarantor as a matter of law or equity (other than the performance of the
obligations contained in such Note and in this Guarantee).

      The Holder of the Note upon which this Guarantee is endorsed is entitled
to the further benefits relating hereto set forth in the Indenture. No reference
herein to the Indenture and no provision of this Guarantee or of the Indenture
shall alter or impair the guarantee of the Guarantor, which is absolute and
unconditional, of the due and punctual payment of the principal of and interest,
or any such other payments, on the Note upon which this Guarantee is endorsed.

      This Guarantee shall be governed by and construed in accordance with the
laws of the State of New York, without giving effect to the conflicts of laws
principles thereof.

      All terms used in this Guarantee which are defined in the Indenture shall
have the meanings assigned to them in the Indenture.

      This Guarantee shall not be valid or obligatory for any purpose until the
certificate of authentication on the Note upon which this Guarantee is endorsed
shall have been executed by the Trustee under the Indenture by the manual
signature of one of its authorized officers.

                                       11
<PAGE>

      IN WITNESS WHEREOF, the Guarantor has caused this Guarantee to be duly
executed.

                                             PLATINUM UNDERWRITERS
                                             HOLDINGS, LTD.

                                             By:________________________________
                                                Name:
                                                Title:

Attest:

By:________________________________
   Name:
   Title:

                                       12
<PAGE>

                                   ASSIGNMENT

FOR VALUE RECEIVED, the undersigned assigns and transfers this Note to:

_________________________________________________________

_________________________________________________________

_________________________________________________________

        (INSERT ASSIGNEE'S SOCIAL SECURITY OR TAX IDENTIFICATION NUMBER)

_________________________________________________________

_________________________________________________________

_________________________________________________________

                   (INSERT ADDRESS AND ZIP CODE OF ASSIGNEE)

agent to transfer this Note on the Register. The agent may substitute another to
act for him or her.

Dated:

                                               Signed:______________________

                                               Signature Guarantee:

       (SIGN EXACTLY AS YOUR NAME APPEARS ON THE OTHER SIDE OF THIS NOTE)

      Signatures must be guaranteed by an "eligible guarantor institution"
meeting the requirements of the Registrar, which requirements include membership
or participation in the Security Transfer Agent Medallion Program ("STAMP") or
such other "signature guarantee program" as may be determined by the Registrar
in addition to, or in substitution for, STAMP, all in accordance with the
Securities Exchange Act of 1934, as amended.

                                       13<PAGE>

                                                                   EXHIBIT 4.7

                              FORM OF GUARANTEE

            For value received, Platinum Underwriters Holdings, Ltd., a
corporation organized under the laws of Bermuda (herein called the "Guarantor",
which term includes any successor under the Indenture referred to in the Note
upon which this Guarantee is endorsed), hereby absolutely, fully and
unconditionally and irrevocably guarantees to the Holder of the Note upon which
this Guarantee is endorsed, and to the Trustee on behalf of such Holder, (a) the
due and punctual payment of the principal of and interest (and, if applicable,
the Redemption Price) on such Note, whether at the Stated Maturity or by
acceleration, call for redemption or otherwise, (b) the due and punctual payment
of interest on overdue principal of and interest on such Note, if any, if
lawful, and (c) the due and punctual payment of any and all other payments due
to the Holder, all in accordance with the terms of such Note and of the
Indenture. In case of the failure of the Company punctually to make any such
payment of principal, premium, if any, or interest, if any, the Guarantor hereby
agrees to cause any such payment to be made punctually when and as the same
shall become due and payable, whether at the Stated Maturity or by declaration
of acceleration, call for redemption or otherwise, and as if such payment were
made by the Company.

            The Guarantor hereby agrees that its obligations hereunder are a
guaranty of payment and not a guaranty of collection or performance and shall be
unconditional and absolute, irrespective of the validity, regularity or
enforceability of such Note or the Indenture or any limitation of the Company
thereunder or any limitation on the method or terms of payment thereunder which
may now or hereafter be caused or imposed in any manner whatsoever, the absence
of any action to enforce the same, any waiver or consent by the Holder of such
Note or by the Trustee with respect to any provisions thereof or of the
Indenture, the obtaining of any judgment against the Company or any action to
enforce the same or any other circumstance which might otherwise constitute a
legal or equitable discharge or defense of a guarantor. The Guarantor hereby
waives the benefits of division and discussion, diligence, presentment, demand
of payment, filing of claims with a court in the event of insolvency or
bankruptcy of the Company, any right to require a proceeding first against the
Company, protest or notice with respect to such Note or the indebtedness
evidenced thereby and all demands whatsoever, and covenants that this Guarantee
will not be discharged except by complete performance of the obligations
contained in such Note and in this Guarantee. Without limiting the generality of
the foregoing, the Guarantor hereby agrees that the obligations of the Guarantor
hereunder shall not be released, affected or impaired by assignment or transfer
in whole or in part of the Note whether or not made without notice to or the
consent of the Guarantor and shall not be subject to any reduction, limitation,
impairment or termination for any reason, including any claim of waiver,
release, surrender, alteration or compromise, and shall not be subject to any
defense of, including, but not limited to, setoff, counterclaim, recoupment or
termination whatsoever, and that such obligations shall not be released,
affected or impaired regardless of whether or not any Holder, including the
Holder of the Note, or anyone on behalf of any such Holder shall have instituted
any suit, action or proceeding or

<PAGE>

exhausted its remedies or taken any steps to enforce any rights against the
Company or any other person to compel any such performance or observance or to
collect all or part of any such amount, either pursuant to the provisions of the
Indenture or the Note or at law or in equity, and regardless of any other
condition or contingency, or by reason of the invalidity, illegality or
unenforceability of the Note or the Indenture or otherwise and that such
obligations shall not be discharged or impaired or otherwise affected by the
failure of the Trustee or any Holder of such Note to assert any claim or demand
or to enforce any remedy under the Indenture or such Note, any other guarantee
or any other agreement, by any waiver, amendment, indulgence or modification
(whether material or otherwise) of any provision of any thereof, by any default,
failure or delay, willful or otherwise, in the performance of any obligations
under the Indenture, the Note or this Guarantee, or by the voluntary or
involuntary liquidation, sale or other disposition of all or substantially all
of the assets of the Company or the Guarantor, or any receivership, insolvency,
bankruptcy, reorganization, or other similar proceedings, affecting the Company
or any of its assets, or the release of any property from the lien and security
interest created by the Indenture or the Note or of any other security for the
Note, or the release or discharge of the Company or the Guarantor from the
performance or observance of any agreement, covenant, term or condition
contained in the Indenture or the Note by operation of law, or the merger or
consolidation of the Company or the Guarantor, or any other cause, whether
similar or dissimilar to the foregoing, or by any other act or omission that may
or might in any manner or to any extent vary the risk or obligations of the
Guarantor or that would otherwise operate as a discharge of a surety or
guarantor as a matter of law or equity (other than the performance of the
obligations contained in such Note and in this Guarantee).

            The Holder of the Note upon which this Guarantee is endorsed is
entitled to the further benefits relating hereto set forth in the Indenture. No
reference herein to the Indenture and no provision of this Guarantee or of the
Indenture shall alter or impair the guarantee of the Guarantor, which is
absolute and unconditional, of the due and punctual payment of the principal of
and interest, or any such other payments, on the Note upon which this Guarantee
is endorsed.

            This Guarantee shall be governed by and construed in accordance with
the laws of the State of New York, without giving effect to the conflicts of
laws principles thereof.

            All terms used in this Guarantee which are defined in the Indenture
shall have the meanings assigned to them in the Indenture.

            This Guarantee shall not be valid or obligatory for any purpose
until the certificate of authentication on the Note upon which this Guarantee is
endorsed shall have been executed by the Trustee under the Indenture by the
manual signature of one of its authorized officers.

<PAGE>

            IN WITNESS WHEREOF, the Guarantor has caused this Guarantee to be
duly executed.

                                             PLATINUM UNDERWRITERS
                                             HOLDINGS, LTD.

                                             By:________________________________
                                             Name:
                                             Title:

Attest:

By:
    ____________________________
Name:
Title:

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00049-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00049-of-00352.parquet"}]]