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                                                                   EXHIBIT 10.20

                                 ADDENDUM NO. 2

                                     TO THE

                        QUOTA SHARE REINSURANCE AGREEMENT
                           DATED AS OF MARCH 27, 2003

              (HEREINAFTER REFERRED TO AS THE "ORIGINAL AGREEMENT")

                                     BETWEEN

                            PLATINUM RE (UK) LIMITED

                   (HEREINAFTER REFERRED TO AS THE "COMPANY")

                                       AND

                       PLATINUM UNDERWRITERS BERMUDA, LTD

                  (HEREINAFTER REFERRED TO AS THE "REINSURER")

WHEREAS, the Reinsurer and the Company are parties to the Original Agreement.

NOW THEREFORE, effective from the Commencement of the Original Agreement, the
parties hereto hereby agree to amend the said agreement as follows:

      Article 4 - PREMIUMS AND COMMISSIONS. The existing clause shall be deleted
      in its entirety and replaced with the following:

      "As premium for the reinsurance provided hereunder, the Retrocedant shall
      retrocede to the Retrocessionaire fifty-five percent (55%) of the Gross
      Net premium ceded to the Retrocedant under the Reinsurance Contracts.

      The Retrocessionnaire shall pay a ceding commission equal to the sum of
      (1) applicable ceding and other commissions, (2) brokerage, (3) taxes, and
      (4) other expenses associated with underwriting the Reinsurance Contracts.

      Other expenses associated with underwriting shall be limited to a maximum
      of 10 percent (10%) of the Gross Net Premium ceded to the Retrocedant
      under the Reinsurance Contracts.

      Gross Net Premium is defined as the total sum of all premiums associated
      with Reinsurance Contracts ceded to the Retrocedant, less: (1) return
      premiums, and (2) ceded reinsurance premium."

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      Article 8 - REPORTS AND REMITTANCES. The existing clause shall be deleted
      in its entirety and replaced with the following:

      "The retrocedant shall render separately, monthly statements of account,
      in arrears, in respect of each year of account, showing the total of all
      premiums, written, paid loss and loss adjustment expenses, allowances,
      commissions, and underwriting expenses relevant to that month. Such
      accounts shall be rendered, as soon as possible after the close of the
      relevant month with the balance payable within 45 days after the end of
      the respective month.

      The retrocedant shall normally debit the retrocessionaire with their
      proportionate share of paid losses and loss adjustment expenses in the
      monthly accounts rendered. The retrocedant may, however, at their
      discretion, request the retrocessionaire to make immediate payment for
      their proportion of any settled loss in excess of (pound)2 million for any
      one loss relating to this agreement; provided that the retrocessionaire
      shall have the right to deduct from any such payment any sums due to the
      retrocessionaire under this agreement for any agreement renewing or
      replacing this agreement.

      In addition, the Retrocedant will furnish the Retrocessionaire a quarterly
      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 expense, and such other
      information as may be required by the Retrocessionaire for completion of
      its annual statements or other filings."

All other terms and conditions of the Original Agreement remain unchanged.

In Witness Whereof, the parties hereto have caused this Addendum No.2 to be
executed by their duly authorized representatives.

                                           Platinum Underwriters Bermuda, Ltd.

                                           By: /s/ Francois Bertrand
                                               -------------------------------
                                           Name: Francois Bertrand
                                           Title: Senior Vice President

                                           Platinum Re (UK) Limited

                                           By: /s/ Les Waters
                                               -------------------------------
                                           Name: Les Waters
                                           Title: Senior Underwriter

                                                                     Page 2 of 2<PAGE>
                                                                   Exhibit 10.21

[PLATINUM LOGO]

                       EXECUTIVE RETIREMENT SAVINGS PLAN
                                 (EXCESS PLAN)
                            SUMMARY PLAN DESCRIPTION

The following is a brief summary of the features of the Platinum Underwriters
Reinsurance, Inc. Executive Retirement Savings Plan.  You are being provided
with this summary of the key features of the Plan in order to help you
understand this important benefit.  The plan is "Non-qualified", meaning it is
not qualified under Section 401 of the Internal Revenue Code.  However, the
amounts contributed to the plan by your employer are not subject to Federal and
State income tax until distributed from the plan.  Until distribution, the
contributions and any earnings are held in an irrevocable trust known as a
"rabbi trust" by an independent trustee, Fidelity Management Trust Company.  The
trust assets must remain subject to the Employer's creditors in the event of
insolvency in order to avoid current income taxation.

WHO MAY JOIN THE PLAN:

You are eligible to participate in the Plan if you are in the following eligible
class:  Participants in the Platinum Underwriters Reinsurance, Inc. Retirement
Savings Plan with a base salary in excess of the limit of Section 401(a)(17) of
the Code of the year ($200,000 in 2003). Once you satisfy these requirements you
will become a participant in the Plan immediately.

COMPANY MATCHING CONTRIBUTIONS:

The Employer shall make a matching offset contribution to Participants who have
made deferrals of at least the maximum allowed pursuant to Section 402(g) of the
Code ($12,000 for 2003).  The contribution is an amount equal to the difference
between the match that you would have received under the Platinum Underwriters
Reinsurance, Inc. Retirement Savings Plan (the "401(k) Plan") if the code did
not apply any limitations to such match and the amount actually contributed due
to limitations imposed by the Code.

You are required to be employed by Platinum as of the last day of the Plan Year
in order to be eligible for matching contributions made for that year.  Matching
contributions will be calculated based on the period ending each Plan Year.

COMPANY PROFIT SHARING CONTRIBUTIONS:

The Company may make discretionary contributions, if any, in an amount to be
determined by the Board of Directors following the end of the Plan Year.

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You are required to be employed by Platinum as of the last day of the Plan Year
in order to be eligible for contributions made for that year.  Contributions
will be calculated based on the period ending each Plan Year.

COMPENSATION:

Eligible compensation for determining contributions is your taxable compensation
for the Plan Year, which is reported on IRS Form W-2.  This includes salary
reduction contributions you made to an Employer sponsored benefit plan or 401(k)
Plan.  Excluded from compensation are reimbursements or other expense
allowances, fringe benefits, moving expenses, deferred compensation and welfare
benefits.

VESTING:

The term "vesting" refers to the portion of your account balance that you are
entitled to under the plan's rules.

Employer match and discretionary contributions are vested according to the
following schedule:

          Years of Service for Vesting         Percentage
          ----------------------------         ----------
                 Less than 1                         0
                      1                              0
                      2                            100

Service for purposes of vesting includes service with the St. Paul Companies.

INVESTMENT OPTION EXCHANGE POLICIES:

You may move among the Plan's investment options or redirect your future
contributions simply by logging on to Fidelity NetBenefits(SM) at www.401k.com
or by calling 1-800-835-5097.  You may contact a Fidelity Participant Services
Representative between 8:30 AM and 8:00 PM (ET) on any business day.  Exchanges
requested before 4:00 PM (ET) will be posted on that business day's closing
price. Unless otherwise noted, transaction requests that are confirmed after the
close of the market, normally 4:00 PM (ET), or on weekends or holidays will
receive the next available closing price.  The minimum exchange is the lesser of
$250 or 100% of your account balance in the investment option.  If your exchange
is less than $250, then it may only be exchanged into one investment option.
Please contact your Plan Administrator or a Fidelity Participant Services
Representative at 1-800-835-5097 for more information.

You may contact Fidelity by logging on to Fidelity NetBenefits(SM) at
www.401k.com or by calling 1-800-835-5097 to obtain a mutual fund prospectus or
information about any of the mutual funds available through the Plan.  The
mutual funds available in your Plan reserve the right to modify or withdraw the
exchange privilege.

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An investment in a money market fund is not insured or guaranteed by the FDIC or
any other government agency.  Although money market funds seek to preserve the
value of your investment at $1.00 per share, it is possible to lose money by
investing in these funds.

ACCESS TO YOUR MONEY:

You will receive a lump sum distribution from the Plan upon termination of
employment.  Your beneficiary will receive your distribution(s) in the event of
your death.  You will pay income tax on any distribution you receive.

You may request a hardship withdrawal, if you qualify, from your vested
accounts. Unlike in your qualified plan, hardship withdrawals in a non-qualified
deferred compensation plan may only be taken in case of an unforeseeable
emergency.  Please see your Plan Administrator for details. The minimum hardship
withdrawal is $1,000.  Distributions will be taxed as ordinary income.

INFORMATION ON YOUR ACCOUNT:

Your account statement is available online through NetBenefits(SM) at
www.401k.com.  You can view and print a statement for any time period up to 24
previous months.  Information available includes transactions, balances and your
personal rate of return.   A hard copy statement will also be automatically
mailed to you four times a year.  You can suppress these statements from being
mailed to your home by logging on to NetBenefits(SM), and selecting "Mail
Preferences" under the Savings tab.

FIDELITY NETBENEFITS(SM)

As an employee or account holder in the plan, you have access to Fidelity
NetBenefits(SM). Through Fidelity NetBenefits(SM) you have access through the
Accounts tab to your account information, exchanges and investment information.
Through the Planning tab you have access to many retirement planning tools.
These tools can assist you in answering questions like, "Am I saving enough to
reach my goals", "What is an appropriate asset allocation strategy for me" and
many more. Through this site you also have access to e-learning Workshops.
e-Learning Workshops provide you the power to conduct your own training on
savings and investing principles. You can access Fidelity NetBenefits(SM) online
at www.401k.com.

FIDELITY PARTICIPANT SERVICES REPRESENTATIVES

Call 1-800-835-5097 between 8:30 am and 8:00 pm (ET) on any business day for
more information on your account.  Representatives can assist with transactions
and answer many of your questions regarding retirement savings.

TO ENROLL:

To begin participating, please complete the enrollment forms to inform your plan
administrator of your participation as well as your designation of beneficiary
forms and send them to your Human Resources Department.

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INVESTMENT OPTIONS:

You may choose among the following investment options for your account:

Fidelity Blue Chip Growth Fund (0312)
Fidelity Diversified International Fund (0325)
Fidelity Equity Income Fund (0023)
Fidelity Low Priced Stock Fund (0316)
Fidelity Mid-Cap Stock Fund (0337)
Fidelity Puritan Fund (0004)
Fidelity Retirement Money Market Portfolio (0630)
Fidelity US Bond Index (0651)
Spartan US Equity Index Fund (0650)
Fidelity Freedom Income Fund (0369)
Fidelity Freedom 2000 Fund (0370)
Fidelity Freedom 2010 Fund (0371)
Fidelity Freedom 2020 Fund (0372)
Fidelity Freedom 2030 Fund (0373)
Fidelity Freedom 2040 Fund (0718)

POINTS TO KEEP IN MIND:

Past performance is no guarantee of future results. Each fund's share
price/yield and return will vary and you may have a gain or loss when you sell
your shares.  For more complete information about any of the mutual funds
available through the plan, including fees and expenses, log on to Fidelity
NetBenefits(SM) at www.401k.com or call Fidelity at 1-800-835-5097 for free
prospectuses. Read them carefully before making your investment choices.

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