Document:

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                                                                    EXHIBIT 10.6

                                                                  EXECUTION COPY

                                LETTER AMENDMENT

                                             Dated as of June 20, 2003

To the banks, financial institutions
   and other institutional lenders
   (collectively, the "Lenders") parties
   to the Credit Agreement referred to
   below and to Citibank, N.A., as agent
   (the "Agent") for the Lenders

Ladies and Gentlemen:

                  We refer to the 364-Day Credit Agreement dated as of June 21,
2002 , and the letter amendments thereto dated as of October 4, 2002 and October
25, 2002 (such Credit Agreement, as so amended, the "Credit Agreement") among
the undersigned and you. Capitalized terms not otherwise defined in this Letter
Amendment have the same meanings as specified in the Credit Agreement.

                  On the terms and conditions stated below, it is hereby agreed
by you and us as follows:

                  The definition of "Termination Date" in Section 1.01 of the
Credit Agreement is, effective as of the date of this Letter Amendment and
subject to the satisfaction of the conditions set forth in the next paragraph,
hereby amended by deleting the date "June 20, 2003" and substituting therefor
the date "August 19, 2003"

                  This Letter Amendment shall become effective as of the date
first above written on the date, on or before June 20, 2003 (the "Amendment
Date"), that the Agent shall have received (a) counterparts of this Letter
Amendment executed by the undersigned and all of the Lenders or, as to any of
the Lenders, advice satisfactory to the Agent that such Lender has executed this
Letter Amendment, (b) a certificate of a duly authorized officer of the
Borrower, dated the Amendment Date, stating that (i) the representations and
warranties contained in Section 4.01 of the Credit Agreement are correct on and
as of the Amendment Date and (ii) no event has occurred and is continuing that
constitutes a Default, (c) a certificate of a duly authorized officer of the
Borrower confirming the information set forth in the certificates delivered by
the Borrower pursuant to Section 3.01(h)(ii) and (iii) of the Credit Agreement
as if such certificates were delivered on and as of the Amendment Date and (d) a
letter from each of Conyers Dill & Pearman, Bermuda counsel to the Borrower, and
Dewey Ballentine LLP, New York counsel to the Borrower, confirming the opinions
delivered pursuant to Section 3.01(h)(iv) of the Credit Agreement as if such
opinions were delivered on and as of the Amendment Date. This Letter Amendment
is subject to the provisions of Section 8.01 of the Credit Agreement.

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                  On and after the effectiveness of this Letter Amendment, each
reference in the Credit Agreement to "this Agreement", "hereunder", "hereof" or
words of like import referring to the Credit Agreement, and each reference in
the Notes to "the Credit Agreement", "thereunder", "thereof" or words of like
import referring to the Credit Agreement, shall mean and be a reference to the
Credit Agreement, as amended by this Letter Amendment.

                  The Credit Agreement and the Notes, as specifically amended by
this Letter Amendment, are and shall continue to be in full force and effect and
are hereby in all respects ratified and confirmed. The execution, delivery and
effectiveness of this Letter Amendment shall not, except as expressly provided
herein, operate as a waiver of any right, power or remedy of any Lender or the
Agent under the Credit Agreement, nor constitute a waiver of any provision of
the Credit Agreement.

                  If you agree to the terms and provisions hereof, please
evidence such agreement by executing and returning at least two counterparts of
this Letter Amendment to Susan L. Hobart, Shearman & Sterling, 599 Lexington
Avenue, New York, New York 10022.

                  This Letter Amendment may be executed in any number of
counterparts and by different parties hereto in separate counterparts, each of
which when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement. Delivery of an executed
counterpart of a signature page to this Letter Amendment by telecopier shall be
effective as delivery of a manually executed counterpart of this Letter
Amendment.

                  This Letter Amendment shall be governed by, and construed in
accordance with, the laws of the State of New York.

                                       Very truly yours,

                                       PLATINUM UNDERWRITERS HOLDINGS, LTD.

                                       By /s/ Gregory E.A. Morrison
                                          -------------------------------------
                                          Title: CEO and President

Agreed as of the date first above written:

CITIBANK, N.A.,
         as Agent and as Lender

By /s/ Michael A. Taylor
   ---------------------------------------
   Title: Vice President

                                       2

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JPMORGAN CHASE BANK

By /s/ Helen L. Newcomb
   --------------------------------------
   Title: Vice President

BANK OF AMERICA, N.A.

By /s/ Leslie Nannen
   --------------------------------------
   Title: Vice President

FLEET NATIONAL BANK

By /s/ George Urban
   --------------------------------------
   Title: Portfolio Manager

STATE STREET BANK AND TRUST COMPANY

By /s/ Edward M. Anderson
   --------------------------------------
   Title: Vice President

                                       3<PAGE>

                                                                    EXHIBIT 10.7

[LETTERHEAD OF PLATINUN(TM)]

June 30, 2003

The St. Paul Companies, Inc.
385 Washington Street
St. Paul, MN 55102

Attention: Mr. Mark Wigmore

RE: MASTER SERVICES AGREEMENT - LETTER AGREEMENT

Gentlemen:

Reference is made to the Master Services Agreement, dated as of November 1,
2002, (the "Agreement") between The St. Paul Companies, Inc. ("St. Paul") and
Platinum Underwriters Holdings, Ltd. ("Platinum"). Capitalized terms used but
not defined herein have the meanings specified in the Agreement.

This letter confirms the agreement between St. Paul and Platinum to modify the
Agreement by (i) extending the Maximum Service Period for the Services provided
by St. Paul or its Post-closing Subsidiaries from June 30, 2003 until June 30,
2004; and (ii) revising the schedule of Services to be provided by St. Paul or
its Post-closing Subsidiaries.

The Agreement shall expire June 30, 2004, subject to the provisions of Section
1(c) of the Agreement. In addition, St. Paul or its Post-closing Subsidiaries
shall provide to Platinum or its Post-closing Subsidiaries each of the Services
specified on Schedule A (Revised) hereto, subject to the provisions of Section
1(f) of the Agreement. All other terms and conditions of the Agreement will
remain in full force and effect.

Sincerely,

PLATINUM UNDERWRITERS HOLDINGS, LTD.

By: /s/ Gregory E.A. Morrison
    -------------------------------------
    Gregory E.A. Morrison
    President and Chief Executive Officer

ACKNOWLEDGED, ACCEPTED AND AGREED:

THE ST. PAUL COMPANIES, INC.

By: /s/ Mark Wigmore
    --------------------------------------
    Mark Wigmore
    Senior Vice President

<PAGE>

SCHEDULE A (Revised)

         1.       Claim processing and payment for all business written on St.
                  Paul paper and subject to the Quota Share Retrocession
                  Agreements (as such term is defined in the Formation and
                  Separation Agreement).

         2.       Billing and collection services for balances due to/from from
                  brokers and cedants for all business written on St. Paul paper
                  and subject to the Quota Share Retrocession Agreements.

         3.       Processing, billing and collection services for all
                  retrocessional premium and loss inuring to the benefit of
                  Platinum for all business written on St. Paul paper subject to
                  the Quota Share Retrocession Agreements.

         4.       Provision of historical underwriting data with respect to the
                  experience of the St. Paul Re division of St. Paul in format
                  to be prescribed by Platinum.

         5.       Provision of ongoing underwriting data with respect to the
                  business ceded to Platinum under the Quota Share Retrocession
                  Agreements.

         6.       Access to or the actual reserving triangles at a reserving
                  class level.

         7.       Accounting guidance for Non-traditional accounts before a
                  commitment is made by Platinum to write the business.<PAGE>

                                                                    EXHIBIT 10.8

                               REFERRAL AGREEMENT
                                     BETWEEN
                     RENAISSANCE UNDERWRITING MANAGERS LTD.
                                       AND
                       PLATINUM UNDERWRITERS BERMUDA, LTD.

This Referral Agreement ("Agreement") is made and entered into by and between
Renaissance Underwriting Managers Ltd. (hereinafter referred to as "RUM") and
Platinum Underwriters Bermuda, Ltd. (hereinafter referred to as the "Company").

The parties hereto agree as herein below, in consideration of the mutual
covenants contained in the following Articles and upon the terms and conditions
as set forth therein:

ARTICLE I: OBLIGATIONS OF THE PARTIES

RUM, a subsidiary of Renaissance Re Holdings Ltd ("Renaissance"), and the
Company have entered into an Agreement whereby RUM will from time to time
provide referrals of treaty and facultative reinsurance contracts to the Company
for compensation as outlined herein. RUM will not retain any liability as
respects those contracts referred except as provided in Article V; and the
Company will be responsible for the management of such business in all respects.

ARTICLE II: TERM

(1)      TERM: This Agreement shall be effective from November 1, 2002 through
         October 31, 2007 as respects treaty and facultative reinsurance
         contracts with inception and/or anniversary dates during the period.

(2)      This Agreement is not cancelable prior to the expiration date by either
         party. Run-off or cut-off of this agreement will be mutually agreed. If
         no agreement can be reached, the contract shall run-off.

ARTICLE III: DEFINITIONS

The following definitions will apply to this Agreement:

(1)      "SUBJECT BUSINESS" will consist of "RENAISSANCE RE GROUP BUSINESS" and
         "DIRECTED BUSINESS" as defined below.

         "RENAISSANCE RE GROUP BUSINESS" is defined as all treaty and
         facultative reinsurance contracts ceded to the Company from companies
         owned or managed by RenaissanceRe Holdings or its subsidiaries.
         Renaissance Re Group Business will be specifically listed in EXHIBIT A,
         to be added to this agreement and updated monthly.

         "DIRECTED BUSINESS" is defined as all treaty and facultative
         reinsurance contracts from unrelated parties written by the Company
         that was directed to the Company by RUM. Directed Business will be
         specifically listed in either EXHIBIT B or EXHIBIT B PRIME, to be added
         to the Agreement and updated monthly, or as contracts are added. The
         Company has the sole right to determine which contracts will be added
         to the list in EXHIBIT B and EXHIBIT B PRIME. Contracts listed in
         Exhibit B shall be considered Directed Business for all renewals until
         the Termination of this Agreement. Contracts listed

                                                                               1

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         in Exhibit B Prime shall only be considered Directed Business for the
         annual period listed on Exhibit B Prime.

         At the time of referral of potential Subject Business, the parties will
         clearly indicate in which Exhibit the contracts will be included.

(2)      "AGREEMENT" means this Agreement, together with the exhibits hereto, as
         the same may be amended in accordance herewith from time to time.

(3)      "ANNUAL PERIOD" as used herein will initially be from November 1, 2002
         to October 31, 2002 and each 12-month period thereafter until the
         expiration of this Agreement on October 31, 2007.

(4)      "AVERAGE QUARTERLY EXPERIENCE ACCOUNT BALANCE" means, for the purpose
         of Article IV(3) hereof, the sum of the Interest Credit Base on the
         last day of the current quarter plus the Interest Credit Base on the
         last day of the immediately prior quarter, multiplied by 0.50. However,
         for the initial quarter of this Agreement, the Average Quarterly
         Experience Account Balance shall equal the Interest Credit Base on the
         last day of such quarter multiplied by 0.50.

(5)      "AVERAGE QUARTERLY ONE-YEAR TREASURY NOTE RATE" means, for the purpose
         of Article IV(3) hereof, the one-year Treasury Note rate prevailing on
         the last day of the applicable quarter, multiplied by 90 divided by
         360.

(6)      "GROSS LOSSES INCURRED" means, for the purpose of Article IV(2) hereof,
         for each Annual Period, the gross losses and loss adjustment expenses
         paid as of the date of calculation, plus the ceded reserves for losses
         and loss adjustment expenses outstanding as of the same date (including
         any ceded reserves for incurred but not reported loss as carried on the
         audited financial statements of the Company), it being understood and
         agreed that all losses and related loss adjustment expenses under the
         policies allocated to an Annual Period shall be charged to the annual
         period, regardless of the date said losses actually occur.

(7)      "GROSS PREMIUMS WRITTEN" means, for the purpose of Article IV hereof,
         all direct premiums written by the Company related to Subject Business,
         without deduction for any premiums ceded by the Company or premiums
         paid for reinsurance recoveries which inure to the benefit of the
         Company.

(8)      "INTEREST CREDIT BASE" means, for the purpose of Article IV(3) hereof,
         the year-to-date collected Gross Written Premium minus the year-to-date
         gross losses and loss adjustment expenses paid, minus the year-to-date
         acquisition expenses paid.

ARTICLE IV: FEES AND COMMISSIONS

(1)      FINDER'S FEE

         Within 30 days following each Annual Period, the Company shall pay to
         RUM a Finder's Fee on the Directed Business included in EXHIBIT B and
         EXHIBIT B PRIME written by the Company pursuant to this Agreement for
         the Annual Period.

         The Finder's Fee Rate shall be 1.0% percent of Gross Written Premium
         for all pro-rata business, 2.5% of Gross Written Premium on all excess
         of loss business, and 7.5% of the margin on all finite business. The
         Finder's Fee will not apply to the portion of the premium retroceded to
         Renaissance Reinsurance, Ltd. pursuant to Article V.

                                                                               2

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         The Finder's Fee Payment will be the calculated based on the Finder's
         Fee Rate as indicated in the preceding paragraph and will be deemed to
         be final when paid. The determination as to what constitutes pro-rata,
         excess of loss and finite business will be mutually agreed by RUM and
         the Company. Margin will be calculated on finite business by a method
         mutually agreed by both parties.

(2)      PROFIT COMMISSION

         This Profit Commission article will apply to all Subject Business
         included in this Agreement as listed in EXHIBITS A, the "Renaissance Re
         Group Business" and EXHIBIT B and EXHIBIT B PRIME, the "Directed
         Business".

         In consideration of the services rendered by RUM pursuant to this
         Agreement, the Company shall pay RUM a Profit Commission in respect of
         the each Annual Period. RUM shall calculate the amount of Profit
         Commission due for each Annual Period. The Profit Commission will be
         resettled 30 days following the end of each Annual Period until all
         income and liability for the Subject Business applicable to that Annual
         Period is extinguished or until mutually agreed by both parties.

         The Amount of Profit will be equal to the positive balance, if any,
         derived from the following formula: the earned portion of Gross
         Premiums Written less the sum of: (i) Gross Losses Incurred and (ii)
         actual expenses paid (direct expenses including but not limited to
         brokerage and FET) by the Company on Subject Business plus an interest
         credit, calculated at the option of RUM.

         The Profit Commission Rate for each Annual Period shall be twenty (20%)
         percent. The Profit Commission shall be equal to the Amount of Profit
         multiplied by the Profit Commission Rate.

         The Company will calculate and provide interim reports of the Profit
         Commission as of each September 30th within 30 days following each
         Annual Period. There will be a separate profit commission calculation
         for each Annual Period with unlimited deficit carry forward. As
         respects each calculation, any additional Profit Commission due RUM
         shall be paid by the Company with the report, and any return Profit
         Commission shown to be due the Company shall be paid by RUM within 30
         days after receipt of the report.

         Profit Commission shall not apply to the portion of the premium
         retroceded to RUM, pursuant to Article V.

(3)      INTEREST CREDIT

         This Interest Credit article will apply to all Subject Business
         included in this Agreement as listed in EXHIBIT A, the "Renaissance Re
         Group Business", EXHIBIT B and EXHIBIT B PRIME, the "Directed
         Business", and RUM will have the right to calculate a quarterly
         Interest Credit on the funds held by the Company in respect of the
         applicable Subject Business. As set forth in Appendix I hereto, the
         Interest Credit will equal the Average Quarterly Experience Account
         Balance (as defined in Article III herein) multiplied by the applicable
         Average Quarterly one-year US Treasury Note rate (as defined in Article
         III herein). The Company agrees to provide the quarterly premium
         collected, loss and loss adjustment expenses paid and acquisition
         expenses paid for the purpose of this calculation, at the end of each
         Annual Period, and shall pay the Interest Credit concurrently with the
         Annual Profit Commission payment, if requested by RUM.

                                                                               3

<PAGE>

ARTICLE V: RETROCESSION OF SUBJECT BUSINESS

(1)      OPTION TO RETROCEDE CONTRACTS: At the sole option of RUM, RUM will have
         the right to designate individual contracts from the Directed Business
         listed in EXHIBIT B and EXHIBIT B PRIME to be retroceded to Renaissance
         Reinsurance Ltd. No more than 30% of Company's signed line may be
         retroceded. The contracts designated by RUM to be retroceded will be
         included in this Agreement as an EXHIBIT C to be attached to this
         Agreement and updated monthly, or as contracts are added.

(2)      AGGREGATE CAP TO RETROCEDED CONTRACTS: As respects those contracts
         retroceded to Renaissance Reinsurance Ltd. in Article V (1) above, RUM
         at its sole option, can designate which of those contracts listed in
         EXHIBIT C will be subject to an Aggregate Loss Ratio Cap provided by
         the Company. Those contracts designated by RUM will be listed
         specifically in an EXHIBIT D to be attached to this Agreement and
         updated monthly, or as contracts are added. The Aggregate Loss Ratio
         Cap provided by the Company will limit the maximum liability from those
         contracts listed in EXHIBIT D to 225% of Gross Premiums Written for
         each annual period. The Aggregate Loss Ratio Cap will apply to the
         combined performance of all contracts listed in EXHIBIT D. At the time
         of referral of potential Subject Business, the parties will clearly
         indicate in which Exhibit the contracts will be included.

(3)      EXPENSE OVERRIDE: As of each September 30th, RUM will pay an Expense
         Override Payment in consideration of the Aggregate Loss Ratio Cap
         provided by the Company in Article V (2) above.

         The Expense Override Rate shall be 3.0% percent.

         The Expense Override Payment will be the product of the Expense
         Override Rate times the Gross Premiums Written for the Contracts listed
         in EXHIBIT D. The Expense Override Payment shall be payable
         simultaneously with the Finder's Fee in Article IV (1).

ARTICLE VI: TERMS AND CONDITIONS

(1)      This Agreement shall not restrict the rights or ability of RUM to offer
         services similar to those contemplated hereby to third parties
         including its own affiliates. The Company waives any claim based on any
         conflict of interest on the part of RUM or its employees arising from
         any RUM affiliate carrying on business similar to that of the Company.

(2)      If any part of this Agreement shall be adjudged by any court of
         competent jurisdiction to be invalid, such judgment will not affect or
         nullify the remainder of this Agreement but the effect thereof will be
         confined to the part immediately involved in the controversy adjudged.

(3)      The waiver by either party hereto of any breach of this Agreement,
         whether in a single instance or repeatedly, shall not be construed as a
         waiver of rights under this Agreement to terminate the same because of
         similar, additional or future breaches. Further, such waiver shall not
         in any manner be construed as a waiver by the other party to strictly
         adhere to the terms and conditions of this Agreement nor as a waiver of
         any claim for damages or other remedy by reason of such breach.

(4)      This Agreement shall be construed and enforced in accordance with, and
         governed by, the laws of Bermuda.

(5)      Without the written consent of the other party, this Agreement may not
         be assigned by either of the parties hereto. Subject to the preceding
         sentence, this Agreement will be binding upon, inure to the benefit of
         and be enforceable by the parties and their respective successors and
         permitted assigns. Any such assignments shall be subject to all
         necessary regulatory approvals.

                                                                               4

<PAGE>

(6)      This Agreement may not be amended, and none of its provisions may be
         modified, except expressly by an instrument signed by the parties
         hereto; provided, however that the parties shall not modify or amend
         any material provision of this Agreement if such action requires the
         prior approval of the Registrar of Companies, without first obtaining
         such approval.

(7)      This Agreement shall not be construed to create the relationship of
         employer or employee, partnership, or any type of joint venture
         relationship, between the Company and RUM.

(8)      Nothing in this Agreement is intended to confer any rights or remedies
         under or by reason of this Agreement on any persons other than RUM and
         the Company and their respective successors. Nothing in this Agreement
         is intended to relieve or discharge the obligations or liability of any
         third persons to RUM or the Company. No provision of this Agreement
         shall give any third persons any right of subrogation or action over or
         against RUM or the Company.

(9)      Except as provided herein, RUM shall not have any other or further
         obligations or responsibilities to the Company, including, but not
         limited to, any liability for the uncollectability of any reinsurance
         premium, the profitability of the business of the Company, the solvency
         of any person (including the Company) or the failure of third parties
         (including insurers and reinsurers) to fulfill their obligations.

(10)     This Agreement, including any exhibits hereto, sets forth the entire
         understanding of the parties with respect to the transactions
         contemplated thereby and hereby, and merges and supersedes all prior
         discussions, agreements, promises, representations, warranties and
         arrangements of every kind and nature between them as to the subject
         matter hereof, and neither party shall be bound by any condition,
         warranty or representation relating to such subject matter other than
         as expressly provided for in the Original Agreement or this Agreement
         or as may be set forth in a subsequent writing signed by the party
         which is to be bound thereby.

(11)     No uncertainty or ambiguity herein shall be construed or resolved
         against either party, whether under any rule of construction or
         otherwise. Neither party to this Agreement shall be considered the
         draftsman. The parties acknowledge and agree that this Agreement has
         been reviewed, negotiated and accepted by the parties and their
         attorneys and shall be construed and interpreted according to the
         ordinary meaning of the words used so as fairly to accomplish the
         purposes and intentions of all parties hereto.

(12)     All notices or other communications that are required or permitted
         hereunder shall be in writing and sufficient if delivered by hand, or
         by courier or overnight carrier, to the Company or RUM at its address
         set forth below (or at such other address as the Company or RUM may
         designate by notice as provided hereunder), and shall be deemed to have
         been delivered as of the date so delivered.

ARTICLE VII: ARBITRATION

(1)      Any dispute arising out of, or related in any way to this Agreement or
         the transactions hereunder, including its formation and validity, shall
         be submitted to a panel of arbitrators sitting in Bermuda. The panel
         shall be composed of two arbitrators, one to be chosen by each party,
         and an umpire to be chosen by the arbitrators. The arbitrators and
         umpire shall be disinterested, active or retired executive officers of
         property or casualty insurance or reinsurance companies, not under the
         control or management of either party to this Agreement.

                                                                               5

<PAGE>

(2)      Each party shall select an arbitrator within 30 days after written
         request for arbitration has been received from the requesting party. If
         either party fails to appoint its arbitrator within 30 days after being
         requested to do so by the other party, the requesting party shall also
         appoint the second arbitrator.

(3)      The panel shall make its decision in the context of the custom and
         usage of the insurance and reinsurance industry. They shall interpret
         this Agreement as an honorable engagement, and shall settle any dispute
         under this Agreement according to an equitable, rather than strictly
         legal, interpretation of its terms with a view to effecting the general
         purpose of this Agreement. The panel is relieved of all judicial
         formality and may abstain from following the strict rules of law. The
         panel shall have the power to fix all procedural rules for the
         arbitration, including but not limited to, the discretionary power to
         make orders regarding any matters which it may consider proper under
         the circumstances of the case relating to pleadings, discovery,
         inspection of documents, and examination of witnesses. The panel shall
         have the power to receive and act upon such evidence, whether oral or
         written, as it in its sole discretion shall deem relevant to the
         dispute.

(4)      The panel shall render a decision in writing within 60 days after the
         matter is finally submitted to it unless the parties agree to an
         extension. Any decision by a majority of the panel members shall be
         final and binding on the parties. If either of the parties fails to
         comply with the panel's decision, the other party may apply for its
         enforcement to a court of competent jurisdiction.

(5)      Unless ordered differently by the panel, each party shall bear the
         expenses of its own arbitrator, and shall jointly and equally bear with
         the other party the expenses of the umpire. In the event both
         arbitrators are chosen by one party, the fees of all three arbitrators
         shall be equally divided between the parties. The remaining costs of
         the arbitration proceeding shall be allocated by the panel as part of
         it award.

IN WITNESS WHEREOF, each party hereto has caused this Agreement to be executed
in its company name by its respective Officer, hereunto duly authorized as of
the date first written above.

PLATINUM UNDERWRITERS BERMUDA LTD.

SIGNED by /s/ Bart Hedges
          ----------------------------------
Name: Bart Hedges
Title: Chief Operating Officer

RENAISSANCE UNDERWRITING MANAGERS LTD.

SIGNED by /s/ John D. Nichols, Jr.
          ---------------------------------
Name: John D. Nichols, Jr.
Title: President

                                                                               6

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