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                                                                EXHIBIT 10(d)(v)

                                CABOT CORPORATION

                      SUPPLEMENTAL RETIREMENT SAVINGS PLAN

                                    PREAMBLE

         Cabot Corporation (the "Corporation") initially adopted the Cabot
Corporation Supplemental Retirement Incentive Savings Plan, a nonqualified
supplemental plan, pursuant to a vote of the Board of Directors of the
Corporation on February 10, 1984. The Supplemental Retirement Incentive Savings
Plan incorporated a supplemental profit-sharing plan previously authorized by
the Board of Directors on September 10, 1976. The Supplemental Retirement
Incentive Savings Plan was amended and restated effective September 9, 1988, and
subsequently amended from time to time. The Corporation adopted the Cabot
Corporation Supplemental Employee Stock Ownership Plan pursuant to a vote of the
Board of Directors, effective September 9, 1988, and subsequently amended from
time to time.

         Effective December 31, 2000, the CRISP was merged with and into the
ESOP, and the combined amended and restated plan was renamed the Cabot
Retirement Savings Plan (the "CRSP"). Similarly, effective December 31, 2000,
the Supplemental Retirement Incentive Savings Plan was merged with and into the
Supplemental ESOP. The combined amended and restated plan, as set forth herein
and renamed the Cabot Supplemental Retirement Savings Plan (the "Plan"), shall
be effective from and after December 31, 2000. The purpose of the Plan is to
provide benefits to a designated group of managers who are highly compensated
employees of the Corporation or its subsidiaries, supplemental to benefits
provided under the CRSP.

         Except as otherwise specifically provided herein, the rights and
benefits, if any, of an individual who was a participant in the Plan (including
any component predecessor plan) and who ceased to be an participant on or prior
to December 31, 2000, will be determined in accordance with the provisions of
the Plan as in effect on the date he or she ceased to be a

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participant.

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                                    SECTION 1

                                   Definitions

         When used herein,, the words and phrases defined shall have the
following meanings unless a different meaning is clearly required by the
context. Terms used herein which are defined in Article 1 of the CRSP shall have
the meanings assigned to them in the CRSP unless a different meaning is set
forth below.

         1.1.     "Applicable Matching Percentage" means (i) for any period for
which Basic Matching Contributions but no Discretionary Matching Contributions
are made under the CRSP, five and five-eighths (5.625%) percent; and (ii) for
any period for which Discretionary Matching Contributions are made under the
CRSP, 5.625% plus the maximum rate (expressed as a percentage of Compensation)
at which Discretionary Matching Contributions are made for such period with
respect to any participant in the CRSP.

         1.2.     "Beneficiary" means the individual(s) or entity(ies) entitled
under Section 3.6 below to receive any benefits hereunder upon the death of a
Supplemental Plan Participant.

         1.3.     "Committee" means the Benefits Committee as defined in the
CRSP.

         1.4.     "Memorandum account" means the account established by the
Corporation on behalf of each Supplemental Plan Participant, to which amounts
described in Sections 3.1 shall be credited. The Committee shall establish such
subaccounts as may be necessary or desirable to implement the terms of this
Plan. A Supplemental Plan Participant's Memorandum Account shall include amounts
accrued under the Cabot Corporation Supplemental Retirement Incentive Savings
Plan and Cabot Corporation Supplemental Employee Stock Ownership Plan as of
December 31, 2000, the effective date of the amendment and restatement of this
Plan.

         1.5.     "Retirement" means termination of employment with the
Corporation and other Affiliated Employers following attainment by the
Supplemental Plan Participant of his or her Early Retirement Age or Normal
Retirement Age. An individual whose employment has terminated by reason of
Retirement shall be treated as having "Retired."

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         1.6.     "Supplemental Plan Participant" has the meaning provided in
Section 2 below.

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                                    SECTION 2

                                  Participation

         2.1.     Participation. Any person who was a participant in the Cabot
Corporation Supplemental Retirement Incentive Savings Plan or Cabot Corporation
Supplemental Employee Stock Ownership Plan on December 31, 2000, will continue
to participate in this Plan in accordance with its terms after such date. Each
other individual who is a participant in the CRSP shall be eligible to
participate in and accrue benefits under this Plan for any calendar year if such
individual satisfies either (i) or (ii) below, and, with respect to accruals
described in Section 3.1(a), also satisfies (iii) below.

                  (a) This Section 2.1(a) is satisfied if such individual's base
         salary for any such year (as determined by the Committee), before
         reduction for deferrals, if any, under the CRSP, the Corporation's
         nonqualified Deferred Compensation Plan, or any salary deferral under
         Sections 125 and 132 of the Code, equals or exceeds the dollar
         limitation applicable to such year under Section 401(a) (17) of the
         Code.

                  (b) This Section 2.1(b) is satisfied if such individual's
         Compensation for such year, reduced for deferrals, if any, under the
         Corporation's nonqualified Deferred Compensation Plan equals or exceeds
         the dollar limitation applicable to such year under Section 401(a)(17)
         of the Code.

                  (c) This Section 2.1(c) is satisfied if, for such year (or for
         such portion of the year during which he or she satisfies the
         requirements of (a) or (b) above) such individual has elected to
         participate in pre-tax deferrals and/or after-tax contributions under
         CRSP to the maximum extent required and permissible thereunder (taking
         into account any limitations imposed under the CRSP to comply with the
         qualification requirements of the Code) to obtain the maximum possible
         Matching Contribution under CRSP.

         For purposes of Section 3(36) of ERISA, the Plan shall be treated as
two separate plans, one of which will be deemed to provide only benefits (if
any) in excess of the limitations of section 415 of the Code.

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                                    SECTION 3

                                    Benefits

         3.1.     Credits to Memorandum Accounts.

                  (a) For each Plan Quarter for which Matching Contributions are
         made to the CRSP, the Committee shall, as soon as practicable after the
         close of such quarter accrue to the Memorandum Account of each
         individual who is a Supplemental Plan Participant for all or any part
         of such period, an amount equal to the excess of (i) the Applicable
         Matching Percentage of the Supplemental Plan Participant's Compensation
         for such period (such Compensation to be determined, solely for this
         purpose, without regard to the limitations described in the last
         paragraph of Section 2.21 of the CRSP, but taking into account the
         limitations described in Section 2.21(b) of the CRSP), over (ii) the
         sum of (A) the amount which is actually allocated to the Supplemental
         Plan Participant's Matching Contribution Account in the CRSP with
         respect to such period, plus (B) any additional credit made for the
         benefit of the Supplemental Plan Participant with respect to such
         period under Section 4(a) (ii) of the Corporation's nonqualified
         Deferred Compensation Plan.

                  (b)(i) As soon as practicable after the end of each Plan Year,
         the Committee shall also accrue to each Supplemental Plan Participant's
         Memorandum Account an amount equal to the amount (if any) that would
         have been contributed for the benefit of the Supplemental Plan
         Participant by his or her Affiliated Employer under Sections 6.5 of the
         CRSP for such Plan Year had the limitations of Sections 401(a) (17) and
         415 of the Code and the corresponding limitations under the CRSP not
         applied and had such contributions and allocations under the CRSP been
         based on Compensation increased (but only if Section 2.1(a) is
         satisfied) by deferrals (if any) under the Corporation's nonqualified
         Deferred Compensation Plan, such amount to be reduced by the amount (if
         any) which is actually contributed and allocated under Section 6.5 of
         the CRSP to the Supplemental Plan Participant's Company Contribution
         Account.

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                  (b)(ii) As soon as practicable after the last business day of
         each Plan Quarter, the Committee shall also accrue to each Supplemental
         Plan Participant's Memorandum Account an amount equal to the amount (if
         any) that would have been contributed to the Supplemental Plan
         Participant's ESOP Allocation Account by his or her Affiliated Employer
         under Sections 7.5 of the CRSP for such Plan Quarter had the
         limitations of Sections 401(a) (17) and 415 of the Code and the
         corresponding limitations under the CRSP not applied and had such
         contributions and allocations under the CRSP been based on Compensation
         increased (but only if Section 2.1(a) is satisfied) by deferrals (if
         any) under the Corporation's nonqualified Deferred Compensation Plan,
         such amount to be reduced by the amount (if any) which is actually
         contributed and allocated to the Supplemental Plan Participant's ESOP
         Allocation Account under Section 7.5 of the CRSP.

                  (c) Amounts accrued hereunder shall be converted to units and
         treated as if invested in the Cabot Stock Fund under the CRSP, except
         as provided in Sections 3.1(d) and 3.1(e) hereof.

                  (d) From and after the date of a Change in Control, each
         memorandum account shall be treated as if invested (i) in a
         fixed-income vehicle earning interest at the rate earned by the most
         currently issued 10-year Treasury Notes on the date of reference or
         (ii) on such other reasonable basis as the Committee shall determine
         from time to time; provided, that this paragraph shall operate to
         change the basis for measuring investment return on Memorandum Accounts
         upon a Change in Control only if such change would then be consistent
         with continued exemption of interests hereunder from the definition of
         "derivative securities" under Rule 16a-1(c) promulgated under the
         Securities Exchange Act of 1934, as amended (or any successor Rule).
         The earnings shall be determined and shall accrue as of each Valuation
         Date until all amounts have been paid to or on behalf of the
         Supplemental Plan Participant.

                  (e) Beginning as of the Valuation Date next following the
         earliest of the Supplemental Plan Participant's becoming a Disabled
         Participant, Retirement, other

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         termination of employment, or death while employed by an Affiliated
         Employer, the Supplemental Plan Participant's account shall be treated
         as if invested (i) in a fixed-income vehicle earning interest at the
         rate earned by the most currently issued 10-year U.S. Treasury Notes on
         the date of reference, or (ii) on such other reasonable basis as the
         Committee shall determine from time to time. The earnings shall be
         determined and shall accrue as of each Valuation Date until all amounts
         have been paid to or on behalf of the Supplemental Plan Participant.

                  3.2. Amount, Form and Timing of Benefit Payments. This Section
         3.2 applies to Supplemental Plan Participants whose Annuity Starting
         Dates are on or after January 1, 2002. Distributions with respect to
         Supplemental Plan Participants whose Annuity Starting Dates are prior
         to January 1, 2002, shall be governed by the provisions of Appendix A.

                  (a) In the event of a Supplemental Plan Participant's
         termination of employment with the Affiliated Employers for any reason,
         his or her vested balance under the Plan shall be paid, or shall
         commence to be paid, as soon as practicable on or after the
         Participant's termination date. For purposes of this paragraph, the
         vested balance of a Supplemental Plan Participant shall mean:

                           (i) in the event of a Supplemental Plan Participant's
                  termination of employment with the Affiliated Employers by
                  reason of Retirement or becoming a Disabled Participant, the
                  entire balance of his or her memorandum Account; and

                           (ii) in the event of a Supplemental Plan
                  Participant's termination of employment with the Affiliated
                  Employers other than by reason of Retirement or becoming a
                  Disabled Participant or death, the product of (A) the balance
                  of his or her Memorandum Account determined under Section 3.1,
                  times (B) the percentage representing the vested interest of
                  such Supplemental Plan Participant in his or her CRSP Account
                  as determined under the vesting rules applicable to a
                  Supplemental Plan Participant's Matching Contribution Account,
                  Company Contributions Account, and ESOP Allocation Account
                  under the CRSP.

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                  (b) (i) A Supplemental Plan Participant shall elect, at such
         time and in such manner as prescribed by the Committee, to receive his
         or her benefits payable under the Plan in either a lump sum payment, or
         in installments for 5, 10 or 15 years. The Supplemental Plan
         Participant may change his or her election to any alternative form of
         payment then available by submitting a new election to the Committee,
         provided, that any such election is submitted at least 13 months prior
         to the Participant's Annuity Starting Date and is accepted by the
         Committee in its sole discretion. The election form most recently
         accepted by the Committee shall govern the payment of the Supplemental
         Plan Participant's Memorandum Account. If a Supplemental Plan
         Participant does not make any election with respect to the payment of
         his or her Memorandum Account, then (A) if such individual terminated
         employment with the Affiliated Employers prior to January 1, 2002, such
         benefits shall be paid in 120 monthly installments, and (B) if such
         individual terminates employment with the Affiliated employers on or
         after January 1, 2002, such benefits shall be paid in a lump sum. If
         the Supplemental Plan Participant's Memorandum Account is to be
         distributed in installments, the amount of each installment shall be
         calculated by dividing the unpaid balance, valued as of the preceding
         Valuation Date, by the number of installments remaining to be paid.

                  (ii) Section 3.2(b)(i) notwithstanding, (A) if the balance of
         the Supplemental Plan Participant's Memorandum Account determined as
         soon as practicable following his or her termination of employment with
         the Affiliated Employers totals less than $50,000, the Committee shall
         distribute the vested balance of such Memorandum Account in a lump sum
         as soon as practicable following such termination, notwithstanding the
         Supplemental Plan Participant's election under the Plan, and (B) if the
         balance of the Supplemental Plan Participant's Memorandum Account on
         his or her Annuity Starting Date totals $50,000 or more, the Committee
         may, in its discretion, accelerate payment of all or any portion of the
         Memorandum Account if it determines such acceleration to be in the
         interests of the Corporation.

                  (c) In the event of a Supplemental Plan Participant's
         termination of

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         employment with the Affiliated Employers by reason of death, the
         balance of his or her memorandum account determined under Section 3.1
         shall be paid in a single sum to the Supplemental Plan Participant's
         Beneficiary as soon as practicable after the receipt by the
         Supplemental Plan Participant's Affiliated Employer of notice of the
         Supplemental Plan Participant's death.

                  (d) If a Supplemental Plan Participant dies prior to the
         complete distribution of his or her vested benefit, the remaining
         installments shall be paid to his or her Beneficiary; provided, that
         upon application by such Beneficiary showing financial hardship or
         other adequate cause as determined by the Committee in its sole
         discretion, the Committee may cause the remaining balance in the
         decedent's memorandum account to be paid in a lump sum to the
         Beneficiary in complete satisfaction of any remaining benefit
         obligation to such Beneficiary hereunder.

                  (e) All amounts payable hereunder shall be paid in cash or in
         whole shares of common Stock of Cabot Corporation as follows:

                           (i) If a Supplemental Plan Participant is employed by
                  the Corporation or an Affiliated Employer on January 1, 2002,
                  then payment shall be made in common Stock.

                           (ii) If a Supplemental Plan Participant is not
                  employed by the Corporation or an Affiliated Employer on
                  January 1, 2002, and such individual's Annuity Starting Date
                  is on or after January 1, 2002, then such payment shall be
                  made in cash, unless such individual irrevocably elects, at
                  such time and in such manner as prescribed by the Committee,
                  to receive payment in common Stock. A Supplemental Plan
                  Participant shall be entitled to make only one such election.
                  Sections 3.2(e)(i) and (e)(2) above notwithstanding, amounts
                  represented by fractional shares of common Stock shall be paid
                  in cash,

         3.3.     Nature of Account. The Memorandum Account maintained by the
Corporation for a Supplemental Plan Participant shall be book-entry account
only, shall hold no actual shares of the Corporation's stock, and shall
represent no interest in or ownership of any such stock.

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Supplemental Plan Participants shall have no voting rights or any other
shareholder rights by reason of participation in this Plan. No Participant, his
Beneficiary or Beneficiaries, or any other person shall have, under any
circumstances, any interest whatever in any particular property or assets of the
Company by virtue of this Plan, and the rights of the Participant, his
Beneficiary or Beneficiaries under this Plan shall be no greater than the rights
of a general unsecured creditor of the Company.

         3.4.     No Payment While Employed. No amounts accrued hereunder on
behalf of a Supplemental Plan Participant may be distributed prior to his or her
termination of employment with the Affiliated Employers or death, as the case
may be. If a Supplemental Plan Participant whose employment has terminated
returns to the employ of an Affiliated Employer, any benefits remaining to be
paid to such Supplemental Plan Participant shall be suspended during the period
of reemployment. Upon his or her subsequent termination of employment, the
Supplemental Plan Participant's memorandum account shall be payable in
accordance with the rules set forth in Section 3.2 above.

         3.5.     Benefits Unfunded. This Plan shall not be construed to create
a trust of any kind or a fiduciary relationship between any Affiliated Employer
and a Supplemental Plan Participant. Neither Supplemental Plan Participants nor
their beneficiaries, nor any other person, shall have any rights against any
Affiliated Employer or its assets in respect of any benefits hereunder, other
than rights as general creditors. Nothing in this Section 3.5, however, shall
preclude an Affiliated Employer from establishing and funding a trust for the
purpose of paying benefits hereunder, if such trust's assets are subject to the
claims of the Affiliated Employer's general creditors in the event of bankruptcy
or insolvency.

         3.6.     Designation of Beneficiary. A Supplemental Plan Participant
may designate, in writing, one or more beneficiaries under this Supplemental
Plan, who may be the same as or different than those named under the CRSP to
receive benefits, if any, payable upon the Supplemental Plan Participant's
death; provided, that in the case of a Supplemental Plan Participant who is
married at time of death, the Supplemental Plan Participant's surviving spouse
shall be treated as the sole Beneficiary unless he or she has consented (in
accordance with

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procedures similar to those in the CRSP relating to spousal consent) to the
designation of one or more other Beneficiaries. In the absence of any
beneficiary so designated, benefits payable following death shall be paid to the
Supplemental Plan Participant's surviving spouse, if any; if none, to such
person or persons (including the decedent's estate) as are designated to receive
any benefits remaining to be paid under the CRSP; or if none of the foregoing,
to such person or persons as shall be designated by the Committee.

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                                    SECTION 4

                               Certain Forfeitures

         4.1.     Termination for Cause. Notwithstanding anything to the
contrary in this Plan, benefits payable hereunder shall be forfeited by the
Supplemental Plan Participant if the Supplemental Plan Participant's termination
of employment was requested by an Affiliated Employer and the termination was
determined by the Committee to be for "cause." For purposes of this Plan,
"cause" shall mean any action or failure to act by the Supplemental Plan
Participant which the Committee in its sole discretion determines to have
constituted negligence or misconduct in the performance of the Supplemental Plan
Participant's duty to his or her Affiliated Employer. Notwithstanding the
foregoing provisions of this Section 4.1, in respect of any termination of a
Supplemental Plan Participant's employment requested by an Affiliated Employer
within the three-year period immediately following a Change in Control, "cause"
shall mean only (i) the willful and continued failure by the Supplemental Plan
Participant to substantially perform his or her duties with his or her
Affiliated Employer, after a written demand for substantial performance is
delivered to the Supplemental Plan Participant by the Affiliated Employer which
demand specifies the manner in which the Affiliated Employer believes that the
Supplemental Plan Participant has not substantially performed the Supplemental
Plan Participant's duties, or (ii) the willful engaging by the Supplemental Plan
Participant in conduct which is demonstrably and materially injurious to the
Affiliated Employer, monetarily or otherwise. For purposes of clauses (i) and
(ii) of the preceding sentence, no act, or failure to act, on the Supplemental
Plan Participant's part shall be deemed "willful" unless done, or omitted to be
done, by the Supplemental Plan Participant not in good faith and without
reasonable belief that the Supplemental Plan Participant's act or failure to act
was in the best interest of the Affiliated Employer.

         4.2.     Other Terminations of Employment. In the event of a
Supplemental Plan Participant's termination of employment other than by reason
of death, Retirement or Total and Permanent Disability, that portion of his or
her Memorandum Account balance that is not payable under Section 3.2(a) shall be
promptly forfeited. If such Supplemental Plan Participant is

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later reemployed by an Affiliated Employer under circumstances entitling him or
her to a restoration of all or a portion of his or her account balance under the
CRSP, the Committee shall make an appropriate corresponding restorative
adjustment to his or her memorandum account hereunder.

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                                    SECTION 5

                                 Administration

         5.1.     Duties of Committee. This Plan shall be administered by the
Committee in accordance with its terms and purposes. The Committee shall
determine, in accordance with Section 3 hereunder, the amount and manner of
payment of the benefits due to or on behalf of each Supplemental Plan
Participant from this Plan and shall cause them to be paid by the Corporation
accordingly. The Committee may delegate its powers, duties and responsibilities
to one or more individuals (including in the Committee's discretion employees of
one or more Affiliated Employers) or one or more committees of such individuals.

         5.2.     Finality of Decision. The decisions made by and the actions
taken by the Committee in the administration of this Plan shall be final and
conclusive with respect to all persons, and neither the Committee nor individual
members thereof, nor its or their delegates hereunder, shall be subject to
individual liability with respect to this Plan.

         5.3.     Benefit Claims; Appeal and Review.

                  (a)      If any person believes that he or she is being denied
         any rights or benefits under this Plan, such person may file a claim in
         writing with the Committee or its designee. If any such claim is denied
         the Committee or its designee will notify such person of its decision
         in writing. Such notification shall be written in a manner calculated
         to be understood by such person and will contain (i) specific reasons
         for denial, (ii) specific reference to pertinent plan provisions, (iii)
         a description of any additional material or information necessary for
         such person to perfect such claim and an explanation of why such
         material or information is necessary, and (iv) information as to the
         steps to be taken if the person wishes to submit a request for review.
         Such notification of will be given within 90 days after the claim is
         received by the Committee or its designee (or within 180 days, if
         special circumstances require an extension of time for processing the
         claim, and if written notice of such extension and circumstances is
         given to such person within the initial 90-day period). If such
         notification is not given within

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         such period, the claim will be considered denied as of the last day of
         such period and such person may request a review of his or her claim by
         the Committee.

                  (b)      Within 60 days after the date on which a person
         receives a written notice of a denied claim (or, if applicable, within
         60 days after the date on which such denial is considered to have
         occurred) such person (or his or her duly authorized representative)
         may (i) file a written request with the Committee for a review of his
         or her denied claim and of pertinent documents and (ii) submit written
         issues and comments to the Committee. The Committee will notify such
         person of its decision in writing. Such notification will be written in
         a manner calculated to be understood by such person and will contain
         specific reasons for the decision as well as specific references to
         pertinent Plan provisions. The decision on review will be made within
         60 days after- the request for review is received by the Committee (or
         within 120 days, if special circumstances require an extension of time
         for processing the request, such as an election by the Committee to
         hold a hearing, and if written notice of such extension and
         circumstances is given to such person within the initial 60-day
         period). If the decision on review is not made within such period, the
         claim will be considered denied.

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                                    SECTION 6

                            Amendment and Termination

         6.1.     Amendment and Termination. While the Corporation intends to
maintain this Plan in conjunction with the CRSP for as long as it deems
necessary, the Board of Directors reserves the right to amend and/or terminate
it at any time for whatever reasons it may deem appropriate; provided, that no
such amendment shall reduce the balance of any Supplemental Plan Participant's
Memorandum Account as of the Valuation Date next preceding the date of such
amendment unless the Participant consents to such reduction.

         Amendments affecting the accrual of benefits hereunder in respect of
Supplemental Plan Participants who are subject to the short-swing profit
provisions of Section 16 of the Securities Exchange Act of 1934, as amended, may
be made no more frequently than once every six (6) months. Notwithstanding any
other provision hereunder, during the three-year period immediately following a
Change in Control, this Plan may not be terminated, altered or amended in a way
that would decrease future accrual of, eligibility for, or entitlement to,
benefits hereunder. This Section 6.1 may not be altered or amended during that
same three-year period in any way except with the prior written consent of all
of the then Supplemental Plan Participants.

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                                    SECTION 7

                                  Miscellaneous

         7.1.     No Employment Rights. Nothing contained in this Plan shall be
construed as a contract of employment between any Affiliated Employer and a
Supplemental Plan Participant, or as giving any Supplemental Plan Participant
the right to be continued in the employment of an Affiliated Employer, or as a
limitation of the right of an Affiliated Employer to discharge any Supplemental
Plan Participant, with or without cause.

         7.2.     Assignment. Subject to the provisions of this Plan relating to
payment of benefits upon the death of a Supplemental Plan Participant, the
benefits payable under this Plan may not be assigned, alienated, transferred,
pledged, or encumbered.

         7.3.     Withholding, Etc. Benefits payable under this Plan shall be
subject to all applicable federal, state or other tax withholding requirements.
To the extent any amount credited hereunder to a Supplemental Plan Participant's
account is treated as "wages" for FICA/Medicare or FUTA tax purposes on a
current basis (or when vested), rather than when distributed, all as determined
by the Committee, then the Committee shall require that the Supplemental Plan
Participant either (i) timely pay such taxes in cash by separate check to his or
her Affiliated Employer, or (ii) make other arrangements satisfactory to such
Employer (e.g., additional withholding from other wage payments) for the payment
of such taxes. To the extent a Supplemental Plan Participant fails to pay or
provide for such taxes as required, the Committee may suspend the Supplemental
Plan Participant's participation in the Plan or reduce amounts credited or to be
credited hereunder.

         7.4.     Distribution of Taxable Amounts. Anything in the Plan to the
contrary notwithstanding, in the event any Supplemental Plan Participant or
Beneficiary is determined to be subject to federal income tax on any amount
credited to the Participant's Memorandum Account prior to the time payment is
otherwise due hereunder, the entire amount determined to be so taxable shall be
paid from the Participant's Memorandum Account to such Participant or
Beneficiary. Any amount to the credit of a Participant's Account shall be
determined to be

                                       18
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subject to federal income tax upon the earlier of:

         (a)      determination by the Internal Revenue Service addressed to the
Participant or Beneficiary which is not appealed; or

         (b)      a final determination by the United States Tax Court or any
other Federal Court affirming any such determination by the Internal Revenue
Service that amounts credited to a Participant's Account are subject to federal
income tax.

         7.5.     No Guarantee of Benefits. Nothing contained in the Plan shall
constitute a guarantee by the Corporation, Affiliated Employer, the Committee,
or any other person or entity that the assets of the Corporation of Affiliated
Employers will be sufficient to pay any benefits hereunder. No Supplemental Plan
Participant shall have any right to receive a benefit payment under the Plan
except in accordance with the terms of the Plan.

         The Corporation, Affiliated Employers, and Committee do not in any way
guarantee any Supplemental Plan Participant's Memorandum Account against loss or
depreciation, whether caused by poor performance of an earnings measure or by
any other event or occurrence. In no event shall the employees, officers,
directors, or stockholders of the Corporation of Affiliated Employers be liable
to any individual or entity on account of any claim arising by reason of the
Plan provisions or any instrument or instruments implementing its provisions, or
for the failure of any Participant, Beneficiary or other individual or entity to
be entitled to any particular tax consequences with respect to the Plan or any
credit or payment hereunder.

         7.6.     Incapacity of Recipient. If any person entitled to a benefit
payment under the Plan is deemed by the Administrator to be incapable of
personally receiving and giving a valid receipt for such payment, then, unless
and until claim therefor shall have been made by a duly appointed guardian or
other legal representative of such person, the Committee may provide for such
payment or any part thereof to be made to any other person or institution then
contributing toward or providing for the care and maintenance of such person.
Any such payment shall be a payment for the account of such person and a
complete discharge of any liability of the Corporation and Affiliated Employers
and the Plan therefor.

         7.7.     Limitations on Liability. Notwithstanding any of the preceding
provisions of

                                       19
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the Plan, neither the Corporation nor Affiliated Employers, nor any individual
acting as employee or agent of the foregoing, nor the Committee shall be liable
to any Supplemental Plan Participant or other person for any claim, loss,
liability or expense incurred in connection with the Plan.

         7.8.     Provisions to Facilitate Plan Operations. If it is impossible
or difficult to ascertain the person to receive any benefit under the Plan, the
Committee may, in its discretion and subject to applicable law, direct payment
to the person it deems appropriate consistent with the Plan's purposes; or
retain such amounts in the Plan for payment to a court pending judicial
determination of the rights thereto. Any payment under this Section 7.8 shall be
a complete discharge of any liability for the making of such payment under the
provisions of the Plan.

         7.9.     Correction of Payment Mistakes. Any mistake in the payment of
a Supplemental Plan Participant's benefits under the Plan may be corrected by
the Committee when the mistake is discovered. The mistake may be corrected in
any reasonable manner authorized by the Committee (e.g., adjustment in the
amount of future benefit payments, repayment to the Plan of an overpayment, or
catch-up payment to a Participant for an underpayment). In appropriate
circumstances (e.g., where a mistake is not timely discovered), the Committee
may waive the making of any correction. A Supplemental Plan Participant or
Beneficiary receiving an overpayment by mistake shall repay the overpayment if
requested to do so by the Committee.

         7.10.    Schedules. The Committee may by Schedule modify the benefits
available hereunder to one or more specified individuals. The provisions of each
such Schedule shall, with respect to the individual or individuals thereby
affected, be deemed a part of the Plan and shall be incorporated herein.

         7.11.    Law Applicable. This Plan shall be construed in accordance
with the laws of the Commonwealth of Massachusetts.

         IN WITNESS WHEREOF, this instrument is executed this 11th day of
December, 2002.

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                                CABOT CORPORATION

                             By: /s/ Robby D. Sisco
                                 ------------------

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                                   APPENDIX A

         This Appendix applies to Supplemental Plan Participants whose Annuity
Starting Dates are prior to January 1, 2002. Distributions with respect to
Supplemental Plan Participants whose Annuity Starting Dates are on or after
January 1, 2002, shall be governed by Section 3.2 of the Plan.

         Section 1. Amount, Form and Timing of Benefit Payments.

                  (a) In the event of a Supplemental Plan Participant's
         termination of employment with the Affiliated Employers (other than by
         reason of Retirement, or becoming a Disabled Participant, or death),
         his or her vested balance under the Plan shall commence to be paid as
         soon as practicable on or after the Participant's Annuity Starting Date
         in the form of 120 monthly installments, each installment calculated by
         dividing the unpaid vested balance, valued as of the preceding
         Valuation Date, by the number of installments remaining to be paid;
         provided, however, that, the Committee in its discretion may accelerate
         payment of all or any portion of the account if it determines such
         acceleration to be in the interests of the Corporation. For purposes of
         this paragraph, the vested balance of a Supplemental Plan Participant
         shall be the product of (A) the balance of his or her Memorandum
         Account determined under Section 3.1 of the Plan, times (B) the
         percentage representing the vested interest of such Supplemental Plan
         Participant in his or her CRSP Account as determined under the vesting
         rules applicable to a Supplemental Plan Participant's Matching
         Contribution Account, Company Contributions Account, and ESOP
         Allocation Account under the CRSP.

                  (b) In the event of a Supplemental Plan Participant becomes a
         Disabled Participant or Retires, the balance of his or her Memorandum
         Account determined under Section 3.1 of the Plan shall be distributed
         at the same time and in the same, manner as the Supplemental Plan
         Participant's benefits under the CRSP, subject to the following special
         rules:

                           (i) If the balance of the Supplemental Plan
         Participant's

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                  Memorandum Account at Retirement or termination of employment
                  totals less than $50,000, the Committee may distribute the
                  accounts in a lump sum (or on some other accelerated basis)
                  notwithstanding the Supplemental Plan Participant's election
                  under the CRSP.

                           (ii) If the Supplemental Plan Participant elects a
                  distribution of a single-life or joint and survivor annuity
                  under Section 9.3(a) (iv) of the CRISP (as such Section
                  appeared prior to the 2000 Restatement of the CRISP), the
                  Committee's discretion as described above to distribute the
                  Memorandum Accounts hereunder on an accelerated basis shall
                  apply regardless of the size of the balance of the
                  Supplemental Plan Participant's Memorandum Account hereunder.

                           (iii) If the Supplemental Plan Participant elects a
                  lump sum payment of his or her CRSP benefit, that election
                  shall be effective with respect to his or her Plan benefit
                  hereunder only with the approval of the Committee. If the
                  Committee does not approve a lump sum payment election, the
                  Supplemental Plan Participant's Memorandum Account hereunder
                  shall be distributed in 120 monthly installments as described
                  at Section (1)(a) above or on such accelerated basis as the
                  Committee may determine.

                           (iv) If the Supplemental Plan Participant's
                  Memorandum Account is to be distributed in installments, the
                  amount of each installment shall be calculated by dividing the
                  unpaid balance, valued as of the preceding Valuation Date, by
                  the number of installments remaining to be paid. Any
                  distribution hereunder that is to be made over the life of the
                  Supplemental Plan Participant or the lives of the Supplemental
                  Plan Participant and his or her Beneficiary shall be based on
                  such reasonable actuarial assumptions as the Committee may
                  determine (which may be different than those applied under the
                  Corporation's qualified plans or those used by commercial
                  insurance companies)

                  (c) In the event of a Supplemental Plan Participant's
         termination of

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         employment with the Affiliated Employers by reason of death, the
         balance of his or her Memorandum Account determined under Section 3.1
         of the Plan shall be paid in a single sum to the Supplemental Plan
         Participant's Beneficiary as soon as practicable after the receipt by
         the Supplemental Plan Participant's Affiliated Employer of notice of
         the Supplemental Plan Participant's death.

                  (d) If a Supplemental Plan Participant described in paragraph
         (a) or (b) dies prior to the complete distribution of his or her vested
         benefit, the remaining installments shall be paid to his or her
         Beneficiary; provided, that upon application by such Beneficiary
         showing financial hardship or other adequate cause as determined by the
         Committee in its sole discretion, the Committee may cause the remaining
         balance in the decedent's memorandum account to be paid in a lump sum
         to the Beneficiary in complete satisfaction of any remaining benefit
         obligation to such Beneficiary hereunder.

                  (e) If the Supplemental Plan Participant elects to roll over
         his or her vested CRSP benefit to the Corporation's Cash Balance Plan,
         the vested balance of his or her Memorandum Account hereunder shall be
         treated as having been transferred to the Corporation's nonqualified
         plan maintained as a supplement to the Corporation's Cash Balance Plan,
         and paid in accordance with the terms of that supplemental plan.

                  (f) All amounts payable hereunder shall be paid in cash only.

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<PAGE>

                                   SCHEDULE X

         Effective May 13, 1994, the Board of Directors deemed it advisable to
provide certain additional benefits to one or more Supplemental ESOP
Participants. Pursuant to such action of the Board, and in accordance with
Section 7.10 of the Plan, the foregoing terms of this Supplemental Retirement
Incentive Savings Plan are modified as follows:

         1. "Schedule X Participant" shall mean Kennett F. Burnes.

         2. Amount of Benefits. The following shall be substituted for Section
3.1(b(ii) of the Plan for the Schedule X Participant:

         "(b)(ii) As soon as practicable after the last business day of each
Plan Quarter, the Committee shall also accrue to each Supplemental Plan
Participant's Memorandum Account an amount calculated as follows:

                  (A). Determine the amount (if any) that would have been
         contributed to the Supplemental Plan Participant's ESOP Allocation
         Account by his or her Affiliated Employer under Sections 7.5 of the
         CRSP for such Plan Quarter had the limitations of Sections 401(a) (17)
         and 415 of the Code and the corresponding limitations under the CRSP
         not applied, and had such contributions and allocations under the CRSP
         been based on Compensation increased (but only if Section 2.1(a) of the
         Plan is satisfied) by deferrals (if any) under the Corporation's
         nonqualified Deferred Compensation Plan.

                  (B). Multiple the result in subsection (A) above by two (2).

                  (C). Reduce the result in subsection (B) above by the amount
         (if any) which is actually contributed and allocated to the
         Supplemental Plan Participant's ESOP Allocation Account under Section
         7.5 of the CRSP for such Plan Quarter."

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