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                                                                     Exhibit 4.5

                                 TRUST AGREEMENT
                                       OF
                              CHUBB CAPITAL TRUST I
                              ---------------------

      This TRUST AGREEMENT, dated as of April 1, 2003 (this "Trust Agreement"),
is entered by and among The Chubb Corporation, a New Jersey corporation, as
Depositor (the "Depositor"), Bank One Delaware, Inc., a Delaware corporation, as
Trustee (the "Delaware Trustee"), Bank One Trust Company, N.A., a national
banking corporation, as Trustee (the "Property Trustee"), and Michael O'Reilly,
not in his individual capacity but solely as Trustee (the "Administrative
Trustee" and collectively with the Delaware Trustee and the Property Trustee,
the "Trustees"). The Depositor and the Trustees hereby agree as follows:

      1. The trust created hereby shall be known as Chubb Capital Trust I (the
"Trust"), in which name the Trustees, or the Depositor to the extent provided
herein, may conduct the business of the Trust, make and execute contracts, and
sue and be sued.

      2. The Depositor hereby assigns, transfers, conveys and sets over to the
Trust the sum of $10. The Trustees hereby acknowledges receipt of such amount in
trust from the Depositor, which amount shall constitute the initial trust
estate. The Trustees hereby declare that it will hold the trust estate in trust
for the Depositor. It is the intention of the parties hereto that the Trust
created hereby constitutes a statutory trust under Chapter 38 of Title 12 of the
Delaware Code, 12 Del. C. Section 3801 et seq. (the "Statutory Trust Act"), and
that this document constitutes the governing instrument of the Trust. The
Trustees are hereby authorized and directed to execute and file a certificate of
trust with the Delaware Secretary of State in accordance with the provisions of
the Statutory Trust Act.

      3. The Depositor and the Trustees will enter into an amended and restated
Trust Agreement, satisfactory to each such party and substantially in the form
included as an exhibit to the 1933 Act Registration Statement (as defined
below), to provide for the contemplated operation of the Trust created hereby
and the issuance of the Preferred Securities and Common Securities referred to
therein. Prior to the execution and delivery of such amended and restated Trust
Agreement, the Trustees shall not have any duty or obligation hereunder or with
respect to the trust estate, and the Depositor shall take or cause to be taken
any action as may be required to obtain any licenses, consents or approvals
required by applicable law or otherwise. Notwithstanding the foregoing, the
Trustees may take all actions requested by the Depositor which the Depositor
deems necessary, convenient or incidental to effect the transactions
contemplated herein. Except as otherwise expressly required by Section 2 herein,
the Trustees shall not have any duty or obligation under or in connection with
this Trust Agreement or any document contemplated hereby, including, without
limitation, with respect to the administration of

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the Trust, and no implied duties or obligations shall be inferred from or read
into this Trust Agreement against or with respect to the Trustees. The Trustees
have no duty or obligation to supervise or monitor the performance of, or
compliance with this Trust Agreement, by the Depositor or any other
beneficiaries, any agents or attorneys-in-fact of the Depositor, or any other
trustee of the Trust. The Trustees shall not be liable for the acts or omissions
of the Depositor or any other beneficiaries, any agents or attorneys-in-fact of
the Depositor, or any other trustee of the Trust nor shall the Trustees be
liable for any act or omission by it in good faith in accordance with the
directions of the Depositor. The right of the Trustees to perform any
discretionary act enumerated herein shall not be construed as a duty.

      4. The Depositor is hereby authorized, (i) to file with the Securities and
Exchange Commission (the "Commission") and execute, in each case on behalf of
the Trust, (a) the Registration Statement on Form S-3 (the "1933 Act
Registration Statement"), including any pre-effective or post-effective
amendments to such 1933 Act Registration Statement (including the prospectus and
the exhibits contained therein), relating to the registration under the
Securities Act of 1933, as amended, of the Preferred Securities of the Trust and
certain other securities and (b) a Registration Statement on Form 8-A (the "1934
Act Registration Statement") (including all pre-effective and post-effective
amendments thereto) relating to the registration of the Preferred Securities of
the Trust under Section 12(b) of the Securities Exchange Act of 1934, as
amended; (ii) to file with the New York Stock Exchange (the "Exchange") and
execute on behalf of the Trust a listing application and all other applications,
statements, certificates, agreements and other instruments as shall be necessary
or desirable to cause the Preferred Securities to be listed on the Exchange;
(iii) to file and execute on behalf of the Trust such applications, reports,
surety bonds, irrevocable consents, appointments of attorney for service of
process and other papers and documents as shall be necessary or desirable to
register the Preferred Securities under the securities or "Blue Sky" laws, and
to obtain any permits under the insurance laws of such jurisdictions as the
Depositor, on behalf of the Trust, may deem necessary or desirable and (iv) to
execute on behalf of the Trust one or more Underwriting Agreements with one or
more underwriters relating to the offering of the Preferred Securities. In the
event that any filing referred to in clauses (i), (ii) and (iii) above is
required by the rules and regulations of the Commission, the Exchange or state
securities or blue sky laws, to be executed on behalf of the Trust by a Trustee,
the Depositor and any Trustee appointed pursuant to Section 6 hereof are hereby
authorized to join in any such filing and to execute on behalf of the Trust any
and all of the foregoing. In connection with all of the foregoing, the Depositor
hereby constitutes and appoints the Chief Executive Officer, the Secretary and
the Treasurer and each of them, as its true and lawful attorneys-in-fact and
agents, with full power of substitution and resubstitution, for the Depositor or
in the Depositor's name, place and stead, in any and all capacities, to sign any
and all amendments (including post-effective amendments) to the 1933 Act
Registration Statement and the 1934 Act Registration Statement and to file the
same, with all exhibits thereto, and other documents in connection therewith,
with the
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Commission, granting unto said attorneys-in-fact and agents full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in connection therewith, as fully to all intents and purposes as the
Depositor might or could do in person, hereby ratifying and confirming all that
said attorneys-in-fact and agents or any of them, or their respective substitute
or substitutes, shall do or cause to be done by virtue hereof.

      5. Each Trustee is authorized to take such action or refrain from taking
such action under this Trust Agreement as it may be directed in writing by the
Depositor from time to time; provided, however, that the Trustee shall not be
required to take or refrain from taking any such action if it shall have
determined, or shall have been advised by counsel, that such performance is
likely to involve the Trustee in personal liability or is contrary to the terms
of this Trust Agreement or of any document contemplated hereby to which the
Trust or the Trustee is a party or is otherwise contrary to law. If at any time
a Trustee determines that it requires or desires guidance regarding the
application of any provision of this Trust Agreement or any other document, or
regarding compliance with any direction it received hereunder, then the Trustee
may deliver a notice to the Depositor requesting written instructions as to the
course of action desired by the Depositor, and such instructions by or on behalf
of the Depositor shall constitute full and complete authorization and protection
for actions taken and other performance by the Trustee in reliance thereon.
Until the Trustee has received such instructions after delivering such notice,
it may refrain from taking any action with respect to the matters described in
such notice.

      6. Bank One Delaware, Inc., in its capacity as Delaware Trustee, shall not
have the powers or the duties of the Trustees set forth herein (except as may be
required under the Statutory Trust Act) and shall be a Trustee hereunder for the
sole and limited purpose of fulfilling the requirements of Section 3807(a) of
the Statutory Trust Act.

      7. The Depositor hereby agrees to (i) reimburse the Trustees for all
reasonable expenses (including reasonable fees and expenses of counsel and other
experts), (ii) indemnify, defend and hold harmless the Trustees and the
officers, directors, employees and agents of the Trustees (collectively,
including the Trustees in their individual capacities, the "Indemnified
Persons") from and against any and all losses, damages, liabilities, claims,
actions, suits, costs, expenses, disbursements (including the reasonable fees
and expenses of counsel), taxes and penalties of any kind and nature whatsoever
(collectively, "Expenses"), to the extent that such Expenses arise out of or are
imposed upon or asserted at any time against such Indemnified Persons with
respect to the performance of this Trust Agreement, the creation, operation,
administration or termination of the Trust, or the transactions contemplated
hereby; provided, however, that the Depositor shall not be required to indemnify
an Indemnified Person for Expenses to the extent such Expenses result from the
willful misconduct, bad faith or gross negligence of such Indemnified Person,
and (iii) advance to each such Indemnified Person Expenses

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(including reasonable fees and expenses of counsel) incurred by such Indemnified
Person, in defending any claim, demand, action, suit or proceeding prior to the
final disposition of such claim, demand, action, suit or proceeding upon receipt
by the Depositor of an undertaking, by or on behalf of such Indemnified Person,
to repay such amount if it shall be determined that such Indemnified Person is
not entitled to be indemnified therefor under this Section 6. The obligations of
the Depositor under this Section 6 shall survive the resignation or removal of
any Trustee, shall survive the termination of this Trust Agreement, except by
amendment and restatement of this Trust Agreement, and shall survive the
transfer by the Depositor of any or all of its interest in the Trust.

      8. This Trust Agreement may be executed in one or more counterparts.

      9. The number of Trustees initially shall be three (3) and thereafter the
number of Trustees shall be such number as shall be fixed from time to time by a
written instrument signed by the Depositor which may increase or decrease the
number of Trustees; provided, however, that to the extent required by the
Statutory Trust Act, one Trustee shall either be a natural person who is a
resident of the State of Delaware or, if not a natural person, an entity which
has its principal place of business in the State of Delaware and otherwise meets
the requirements of applicable Delaware law. Subject to the foregoing, the
Depositor is entitled to appoint or remove without cause any Trustee at any
time. The Trustees may resign upon thirty days' prior notice to the Depositor.

      10. This Trust Agreement shall be governed by, and construed in accordance
with, the laws of the State of Delaware (without regard to conflict of laws
principles).



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      IN WITNESS WHEREOF, the parties hereto have caused this Trust Agreement to
be duly executed as of the day and year first above written.



                                    THE CHUBB CORPORATION, as Depositor

                                    By:     /s/ HENRY G. GULICK
                                            ------------------------------------
                                    Name:   Henry G. Gulick
                                    Title:  Vice President and Secretary


                                    BANK ONE DELAWARE, INC. as Delaware Trustee
                                    of the Trust

                                    By:     /s/ SANDRA L. CARUBA
                                            ------------------------------------
                                    Name:   Sandra L. Caruba
                                    Title:  Senior Counsel


                                    BANK ONE TRUST COMPANY, N.A., as Property
                                    Trustee of the Trust

                                    By:     /s/ SANDRA L. CARUBA
                                            ------------------------------------
                                    Name:   Sandra L. Caruba
                                    Title:  Senior Counsel


                                    MICHAEL O'REILLY, not in his individual
                                    capacity but solely as Administrative
                                    Trustee of the Trust

                                    By:     /s/ MICHAEL O'REILLY
                                            ------------------------------------
                                    Name:   Michael O'Reilly
                                    Title:  Vice Chairman and Chief Financial
                                            Officer