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                             CASUALTY AND SPECIALTY

                       QUOTA SHARE RETROCESSION AGREEMENT

                                 BY AND BETWEEN

                       PLATINUM UNDERWRITERS BERMUDA, LTD.

                                       and

                     PLATINUM UNDERWRITERS REINSURANCE, INC.

     This Casualty and Specialty Quota Share Retrocession Agreement (this
"Agreement"), dated as of January 1, 2007, is made by and between Platinum
Underwriters Bermuda, Ltd., a Bermuda-domiciled insurance company (the
"Retrocessionaire"), and Platinum Underwriters Reinsurance, Inc. a
Maryland-domiciled insurance company (the "Retrocedant").

     NOW THEREFORE, in consideration of the premises and of the mutual promises
set forth herein, Retrocedant and Retrocessionaire agree as follows:

ARTICLE 1 - BUSINESS COVERED

The Retrocedant hereby obligates itself to retrocede to the Retrocessionaire and
the Retrocessionaire hereby obligates itself to accept a sixty percent (60%)
quota share of the reinsurance and retrocession contracts classified by the
Retrocedant under certain reserving classes identified on Schedule 1 hereto and
underwritten by Retrocedant on or after the Effective Date (collectively, the
"Reinsurance Contracts").

ARTICLE 2 - COMMENCEMENT AND TERMINATION

This Agreement shall take effect and shall apply to all Reinsurance Contracts
that incept on or after 12:01 a.m. New York time, January 1, 2007 (the
"Effective Date"). It shall remain continuously in force but may be terminated
by either party giving at least ninety (90) days' notice in writing to the other
party.

Upon the expiration or termination of this Agreement, the Retrocessionaire shall
remain liable hereunder for it's pro rata share of the Reinsurance Contracts
until the expiration, cancellation or termination of the Retrocedant's
liabilities under the Reinsurance Contracts.

ARTICLE 3 - ORIGINAL CONDITIONS

All retrocessions assumed under this Agreement shall be subject to the same
rates, terms, conditions, waivers and interpretations, and to the same
modifications and alterations, as the respective Reinsurance Contracts.

This Agreement is solely between the Retrocedant and the Retrocessionaire, and
in no instance shall any other party have any rights under this Agreement except
as expressly provided otherwise in the Insolvency Article.

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ARTICLE 4 - PREMIUMS

The Retrocedant shall retrocede to the Retrocessionaire an amount equal to sixty
(60%) of Gross Net Premium due under the Reinsurance Contracts.

The Retrocessionaire shall pay a ceding commission equal to the sum of (i) one
hundred percent (100%) of the actual expenses incurred by Retrocedant in
acquiring the business ceded to the Retrocessionaire under this Agreement,
including all commissions and brokerage, and (ii) seven and a quarter percent
(7.25%) of the Gross Net Premium ceded to the Retrocessionaire under this
Agreement.

For purposes of this Agreement, the term "Gross Net Premium" is the amount equal
to (i) the Gross Premium ceded to Retrocedant under the respective Reinsurance
Contracts less (ii) return premium paid or payable by the Retrocedant under the
respective Reinsurance Contracts, and (iii) premiums paid or payable by the
Retrocedant for inuring reinsurance as described in Article 7 hereof.

ARTICLE 5 - EXCLUSIONS

The following Exclusion Clauses are attached to and form part of this Agreement:

     1.   Nuclear Incident Exclusion Clause - Liability - Reinsurance- U.S.A.
          (BRMA 35A).

     2.   Nuclear Incident Exclusion Clause - Liability - Reinsurance - Canada
          (BRMA 35D).

     3.   Pools, Associations, and Syndicates as per Pools, Associations, and
          syndicate Exclusion Clause.

     4.   War Risk Exclusion Clause.

     5.   Insolvency Funds Exclusion Clause.

     6.   Any Excess of Loss Retrocession Agreement by and between Platinum Re
          (UK) Limited and the Retrocedant.

     7.   Reinsurance Contracts subject to certain Collateral Agreements, and
          which the Retrocedant has identified or will identify in Appendix 2 to
          this Agreement.

     8.   Liabilities assumed by the Retrocedant from the Retrocessionaire
          pursuant to any excess of loss retrocession agreement between the
          parties.

ARTICLE 6 - TERRITORY

Coverage applies within the territorial limits of the Reinsurance Contracts
covered hereunder.

ARTICLE 7 - INURING REINSURANCE

It is understood and agreed that when the Retrocedant warrants that it is in the
best interest of the Retrocedant and the Retrocessionaire, Retrocedant may
purchase facultative reinsurance and/or any other treaty reinsurance. The
premium for said inuring reinsurance that inures to the benefit of the
Retrocessionaire will reduce the Gross Net Premium pursuant to Article 4 hereof.

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Notwithstanding the above, facultative and treaty reinsurance listed in Appendix
1 hereto shall not inure to the benefit of the Retrocessionnaire.

ARTICLE 8 - LOSS AND LOSS EXPENSE

Retrocessionaire shall be liable for sixty percent (60%) of all loss, loss
adjustment expenses and other payment obligations as incurred by Retrocedant
under the Reinsurance Contracts on and after the Effective Date net of all
salvages and recoveries under inuring reinsurance.

Notwithstanding the above, Retrocessionaire's maximum liability for loss and
loss expense shall be limited to 230% of the Gross Net Premium ceded to
Retrocessionaire under this Agreement.

ARTICLE 9 - EXTRA CONTRACTUAL OBLIGATIONS

This Agreement shall protect the Retrocedant and any original reinsured, within
the limits hereof, where the loss includes any Extra Contractual Obligations.
The term "Extra Contractual Obligations" is defined as those liabilities not
covered under any other provision of this Agreement and which arise from the
handling of any claim on business covered hereunder, such liabilities arising
because of, but not limited to, the following: failure by any original reinsured
to settle within the policy limit, or by reason of alleged or actual negligence,
fraud, or bad faith in rejecting an offer of settlement or in the preparation of
the defense or in the trial of any action against its insured or reinsured or in
the preparation or prosecution of an appeal consequent upon such action.

The date on which any Extra Contractual Obligation is incurred by any original
reinsured shall be deemed, in all circumstances, to be the date of the original
disaster and/or casualty.

However, this Article shall not apply where the loss has been incurred due (i)
solely to the acts, or failure to act, of the Retrocedant in handling its claims
or (ii) to fraud by a member of the Board of Directors or a corporate officer of
any original reinsured acting individually or collectively or in collusion with
any individual or corporation or any other organization or party involved in the
presentation, defense or settlement of any claim covered hereunder.

ARTICLE 10 - EXCESS OF ORIGINAL POLICY LIMITS

This Agreement shall protect the Retrocedant and any original reinsured, within
the limits hereof, in connection with loss in excess of the limit of its
original policy, such loss in excess of the limit having been incurred because
of failure of the original reinsured to settle within the policy limit or by
reason of alleged or actual negligence, fraud, or bad faith in rejecting an
offer of settlement or in the preparation of the defense or in the trial of any
action against its insured or reinsured or in the preparation or prosecution of
an appeal consequent upon such action.

However, this Article shall not apply where the loss has been incurred due (i)
solely to the acts, or failure to act, of the Retrocedant in handling its claims
or (ii) to fraud by a member of the Board of Directors or a corporate officer of
the original reinsured acting individually or collectively or in collusion with
any individual or corporation or any other organization or party involved in the
presentation, defense or settlement of any claim covered hereunder.

For the purpose of this Article, the word "loss" shall mean any amounts for
which the original reinsured or Retrocedant would have been contractually liable
to pay had it not been for the limit of the original policy.

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ARTICLE 11 - ADMINISTRATION OF REINSURANCE CONTRACTS

          SECTION 11.01 Administration. The parties agree that, as of the
Effective Date, Retrocedant shall have the sole authority to administer the
Reinsurance Contracts in all respects, which authority shall include, but not be
limited to, authority to bill for and collect premiums, adjust all claims and
handle all disputes thereunder and to effect any and all amendments,
commutations and cancellations of the Reinsurance Contracts. Retrocedant shall
not settle any claims, waive any right, defense, setoff or counterclaim relating
to the Reinsurance Contracts with respect to amounts in excess of $5 million or
make any ex gratia payments in each case without the prior written consent of
Retrocessionaire, which consent shall not be unreasonably withheld or delayed.

          SECTION 11.02 Reporting and Regulatory Matters. Each party shall
provide the notices and filings required to be made by it to state regulatory
authorities as a result of this Agreement. Notwithstanding the foregoing, each
party shall provide to the other party any information in its possession
regarding the Reinsurance Contracts as reasonably required by the other party to
make such filings and in a form as agreed to by the parties.

          SECTION 11.03 Duty to Cooperate. Upon the terms and subject to the
conditions and other agreements set forth herein, each party agrees to use its
commercially reasonable efforts to take, or cause to be taken, all actions, and
to do, or cause to be done, and to assist and cooperate with the other party in
doing, all things necessary or advisable to perform the transactions
contemplated by this Agreement.

ARTICLE 12 - FOLLOW THE FORTUNES

It is the intent of this Agreement that the Retrocessionaire shall in every case
in which this Agreement applies and in the proportions specified herein, "follow
the fortunes" of the Retrocedant in respect of risks the Retrocessionaire has
accepted under this Agreement.

ARTICLE 13 - REPORTS AND REMITTANCES

Within thirty (30) days after the close of each month, the Retrocedant will
furnish the Retrocessionaire with a report summarizing the written premium ceded
less return premium, allowances, commission, premiums for inuring reinsurance,
losses paid, loss adjustment expense paid, monies recovered, and net balance due
either party. In addition, the Retrocedant will furnish the Retrocessionaire a
monthly statement showing the unearned premium, the total reserves for
outstanding losses including loss adjustment expense, a breakdown for paid and
outstanding catastrophe losses and loss adjustment expenses, and such other
information as may be required by the Retrocessionaire for completion of its
statutory financial statements and other filings.

The net balance will be paid within forty-five (45) days after the close of the
respective month. Any such amounts payable to the Retrocessionaire shall be paid
into a trust account established under Article 23 hereof, if such trust account
has been established. Should payment due from the Retrocessionaire exceed $5
million as respects any one loss, the Retrocedant may give the Retrocessionaire
notice of payment made or its intention to make payment on a certain date. If
the Retrocedant has paid the loss, payment will be made by the Retrocessionaire
immediately. If the Retrocedant intends to pay the loss by a certain date and
has submitted a satisfactory proof of loss or similar document, payment will be
due from the Retrocessionaire twenty-four (24) hours prior to the date, provided
the Retrocessionaire has a period of seven (7) days after receipt of said notice
to dispatch the payment. Cash loss amounts specifically remitted by the
Retrocessionaire as set forth herein will be credited to its next monthly
account.

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ARTICLE 14 - CURRENCY

For purposes of this Agreement, where the Retrocedant receives premiums or pays
losses in currencies other than United States dollars, such premiums or losses
shall be converted into United States dollars at the actual rates of exchange at
which these premiums or losses are entered in the Retrocedant's books.

ARTICLE 15 - ACCESS TO RECORDS

The Retrocedant shall place at the disposal of the Retrocessionaire at all
reasonable times, and the Retrocessionaire shall have the right to inspect
through its designated representatives, during the term of this Agreement and
thereafter, all books, records and papers of the Retrocedant in connection with
any reinsurance hereunder, or the subject matter hereof.

The Retrocessionaire, except with the express prior written consent of the
Retrocedant, shall not directly or indirectly, communicate, disclose or divulge
to any third party, any knowledge or information that may be acquired either
directly or indirectly as a result of the inspection of the Retrocedant's books,
records and papers. The restrictions as outlined in this Article shall not apply
to communication or disclosures that the Retrocessionaire is required to make to
its statutory auditors, retrocessionaires, legal counsel, arbitrators involved
in any arbitration procedures under this Agreement or disclosures required upon
subpoena or other duly-issued order of a court or other governmental agency or
regulatory authority.

ARTICLE 16 - ARBITRATION

          SECTION 16.01 As a condition precedent to any right of action under
this Agreement, any dispute or difference between the parties hereto relating to
the formation, interpretation, or performance of this Agreement, or any
transaction under this Agreement, whether arising before or after termination,
shall be submitted for decision to a panel of three arbitrators (the "Panel") at
the offices of Judicial Arbitration and Mediation Services, Inc. in accordance
with the Streamlined Arbitration Rules and Procedures of Judicial Arbitration
and Mediation Services, Inc.

          SECTION 16.02 The party demanding arbitration shall do so by written
notice to the responding party. Retrocessionaire hereby appoints its Chief
Operating Officer as its agent to receive any arbitration demand hereunder and
Retrocedant hereby appoints its General Counsel as its agent to receive any
arbitration demand hereunder. The arbitration demand shall state the issues to
be resolved and shall name the arbitrator appointed by the demanding party.

          SECTION 16.03 Within thirty (30) days of receipt of the demand for
arbitration, the responding party shall notify the demanding party of any
additional issues to be resolved in the arbitration and the name of the
responding party's appointed arbitrator. If the responding party refuses or
neglects to appoint an arbitrator within thirty (30) days following receipt of
the written arbitration demand, then the demanding party may appoint the second
arbitrator but only after providing ten (10) days' written notice of its
intention to do so, and only if such other party has failed to appoint the
second arbitrator within such ten (10) day period.

          SECTION 16.04 The two arbitrators shall, before instituting the
hearing, select an impartial arbitrator who shall act as the umpire and preside
over the hearing. If the two arbitrators fail to agree on the selection of a
third arbitrator within thirty (30) days after notification of the appointment
of the second arbitrator, the selection of the umpire shall be made by the
American Arbitration Association. Upon resignation or death of any member of the
Panel, a replacement will be appointed in the same fashion as the resigning or
deceased member was appointed. All arbitrators shall be active or former

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officers of property/casualty insurance or reinsurance companies, or Lloyd's
underwriters, and shall be disinterested in the outcome of the arbitration.

          SECTION 16.05 Within thirty (30) days after notice of appointment of
all arbitrators, the Panel shall meet and determine timely periods for briefs,
discovery procedures and schedules for hearings. The Panel shall have the power
to determine all procedural rules for the holding of arbitration, including, but
not limited to, the inspection of documents, examination of witnesses and any
other matter relating to the conduct of the arbitration. The Panel shall
interpret this Agreement as an honorable engagement and not as merely a legal
obligation and shall make its decision considering the custom and practice of
the applicable insurance and reinsurance business. The Panel shall be relieved
of all judicial formalities and may abstain from following the strict rules of
law. The decision of any two arbitrators shall be binding and final. The Panel
shall render its decision in writing within sixty (60) days following the
termination of the hearing. Judgment upon the award may be entered in any court
of competent jurisdiction.

          SECTION 16.06 Each party shall bear the expense of its own arbitrator
and shall share equally with the other party the expense of the umpire and of
the arbitration.

          SECTION 16.07 Arbitration hereunder shall take place in New York, New
York unless the parties agree otherwise.

          SECTION 16.08 The parties hereto hereby expressly (i) submit to the
jurisdiction of the Panel, (ii) agree to comply with all requirements necessary
to give the Panel jurisdiction and (iii) agree to abide by the final decision of
the Panel.

          SECTION 16.09 This Article 16 shall survive termination of this
Agreement.

ARTICLE 17 - INSOLVENCY

In the event of the insolvency of the Retrocedant, this reinsurance shall be
payable directly to the Retrocedant, or to its liquidator, receiver, conservator
or statutory successor on the basis of reported claims allowed against the
insolvent Retrocedant by any court in a liquidation proceeding, without
diminution because of the insolvency of the Retrocedant or because the
liquidator, receiver, conservator or statutory successor of the Retrocedant has
failed to pay all or a portion of any claim.

It is agreed, however, that the liquidator, receiver, conservator or statutory
successor of the Retrocedant shall give written notice to the Retrocessionaire
of the pendency of a claim against the Retrocedant indicating the Reinsurance
Contract reinsured, which claim would involve a possible liability on the part
of the Retrocessionaire within a reasonable time after such claim is filed in
the conservation or liquidation proceeding or in the receivership, and that
during the pendency of such claim, the Retrocessionaire may investigate such
claim and interpose, at its own expense, in the proceeding where such claim is
to be adjudicated any defense or defenses that it may deem available to the
Retrocedant or its liquidator, receiver, conservator or statutory successor. The
expense thus incurred by the Retrocessionaire shall be chargeable, subject to
the approval of the court, against the Retrocedant as part of the expense of
conservation or liquidation to the extent of a pro rata share of the benefit
which may accrue to the Retrocedant solely as a result of the defense undertaken
by the Retrocessionaire.

As to all reinsurance made, ceded, renewed or otherwise becoming effective under
this Agreement, the reinsurance shall be payable as set forth above by the
Retrocessionaire to the Retrocedant or to its liquidator, receiver, conservator
or statutory successor, except (1) where the Reinsurance Contracts specifically
provide another payee in the event of the insolvency of the Retrocedant, or (2)
where the

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Retrocessionaire with the consent of the insured or reinsureds, has assumed such
Reinsurance Contract obligations of the Retrocedant as direct obligations of the
Retrocessionaire to the payees under such Reinsurance Contracts and in
substitution for the obligations of the Retrocedant to such payees.

ARTICLE 18 - OFFSET

The Retrocedant and the Retrocessionaire shall have the right to offset any
balance or amounts due from one party to the other under the terms of this
Agreement. The party asserting the right of offset may exercise such right at
any time whether the balances due are on account of premiums, losses or
otherwise.

ARTICLE 19 - SALVAGE AND SUBROGATION

The Retrocessionaire will be credited with its share of salvage and/or
subrogation in respect of claims and settlements under this Agreement, less its
share of recovery expense. Should the Retrocedant refuse or neglect to enforce
its right of salvage and/or subrogation, the Retrocessionaire is hereby
empowered and authorized to institute appropriate action in the name of the
Retrocedant.

ARTICLE 20 - FEDERAL EXCISE TAX

The Retrocessionaire will allow for the purpose of paying Federal Excise Tax a
deduction, from the premium payable to the Retrocessionaire hereunder, of an
amount equal to the applicable percentage of such premium representing the
Federal Excise Tax (as imposed under Section 4371 of the Internal Revenue
Service Code) to the extent such premium is subject to such tax. In the event of
any return of premium, the Retrocessionaire will deduct the aforesaid percentage
from the return premium payable hereunder and the Retrocedant or its agent will
recover such tax from the United States Government. In all other instances, if
the Retrocedant should recover any portion of a Federal Excise Tax that was
withheld from the premium paid to the Retrocessionaire, such recovered amount
shall be paid promptly to the Retrocessionaire.

ARTICLE 21 - SERVICE OF SUIT

In the event the Retrocessionaire fails to pay any amount claimed due hereunder,
the Retrocessionaire, at the request of the Retrocedant, will submit to the
jurisdiction of a court of competent jurisdiction within the United States and
will comply with all requirements necessary to give that court jurisdiction.
Nothing in this Article constitutes, or should be understood to constitute, a
waiver of the Retrocessionarie's right to commence an action in any court of
competent jurisdiction in the United States, to remove an action to the United
States District Court, or to seek a transfer of a case to another court as
permitted by the laws of the United States or of any state in the United States.
Service of process in such suit may be made upon Dewey Ballantine LLP, New York,
New York. In any suit instituted against it upon this Agreement,
Retrocessionaire will abide by the final decision of such court or of any
appellate court in the event of an appeal.

The above named are authorized and directed to accept service of process on
behalf of the Retrocessionaire in any such suit and/or upon the request of the
Retrocedant to give a written undertaking to the Retrocedant that they will
enter a general appearance upon the Retrocessionaire's behalf in the event such
a suit is instituted.

Further, pursuant to any statute of any state, territory, or district of the
Untied States that makes provision therefor, the Retrocessionaire hereby
designates the Superintendent, Commissioner, or Director of

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Insurance or other officer specified for that purpose in the statute (or his
successor or successors in office) as its true and lawful attorney upon whom may
be served any lawful process in any action, suit, or proceeding instituted by or
on behalf of the Retrocedant or any beneficiary hereunder arising out of this
Agreement, and hereby designates the above named as the person to which the said
officer is authorized to mail such process or a true copy thereof.

ARTICLE 22 - ERRORS AND OMISSIONS

Any inadvertent delay, omission, error or failure made in connection with this
Agreement shall not relieve either party hereto from any liability which would
attach hereunder if such delay, omission, error or failure had not been made,
provided such delay, omission, error or failure is rectified as soon as
reasonably practicable after discovery.

ARTICLE 23 - SECURITY

If Retrocessionaire is not licensed, or an accredited reinsurer in the State of
Maryland, Retrocessionaire shall establish and maintain a funds withheld
account, trust fund or other form of security for the benefit of Retrocedant as
security for the obligations of Retrocessionaire under this Agreement. The funds
withheld account, trust fund or other form of security shall be in a form
reasonably satisfactory to Retrocedant and shall comply with the requirements
under Maryland Insurance Law applicable to trust funds, funds withheld accounts,
or other forms of security established for credit for reinsurance purposes.

ARTICLE 24 - MISCELLANEOUS PROVISIONS

          SECTION 24.01 Severability. If any term or provision of this Agreement
shall be held void, illegal, or unenforceable, the validity of the remaining
portions or provisions shall not be affected thereby.

          SECTION 24.02 Successors and Assigns. This Agreement may not be
assigned by either party without the prior written consent of the other. The
provisions of this Agreement shall be binding upon and inure to the benefit of
and be enforceable by the parties hereto and their respective successors and
assigns as permitted herein.

          SECTION 24.03 Execution in Counterparts. This Agreement may be
executed by the parties hereto in any number of counterparts and by each of the
parties hereto in separate counterparts, each of which counterparts, when so
executed and delivered, shall be deemed to be an original, but all such
counterparts shall together constitute but one and the same instrument.

          SECTION 24.04 Headings. Headings used herein are not a part of this
Agreement and shall not affect the terms hereof.

          SECTION 24.05 Amendments; Entire Agreement. This Agreement may be
amended only by written agreement of the parties. This Agreement supersedes all
prior discussions and written and oral agreements and constitutes the sole and
entire agreement between the parties with respect to the subject matter hereof.

          SECTION 24.06 Negotiated Agreement. This Agreement has been negotiated
at arm's-length, and the fact that the initial and final drafts will have been
prepared by either party will not give rise to any presumption for or against
any party to this Agreement or be used in any respect or forum in the
construction or interpretation of this Agreement or any of its provisions.

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          SECTION 24.07 Governing Law. This Agreement shall be governed by the
laws of the State of New York without giving effect to any choice or conflict of
laws provision or rule (whether of the State of New York or any other
jurisdiction) that would cause the application of the laws of any jurisdiction
other than the State of New York.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed by their duly authorized representatives as of the date set forth
below.

                                       Platinum Underwriters Bermuda, Ltd.

                                       By: /s/ Les Waters
                                           -----------------------------------
                                            Name:  Les Waters
                                            Title: Vice President
                                            Date:  February 19, 2007

                                       Platinum Underwriters Reinsurance, Inc.

                                       By: /s/ Kevin Marine
                                           -----------------------------------
                                            Name:  Kevin Marine
                                            Title: Senior Vice President
                                            Date: February 12, 2007

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