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                                                                   EXHIBIT 10.20

                         AMENDMENT NO. 3 TO UNOVA, INC.

                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN


        WHEREAS, UNOVA, Inc. (the "Company") has previously adopted the UNOVA,
Inc. Supplemental Executive Retirement Plan as amended by Amendment No. 1
thereto dated September 23, 1998 and Amendment No. 2 thereto dated March 11,
1999 (the "Plan"); and

        WHEREAS, the Board of Directors of the Company deems it desirable that
the Plan be further amended in the manner set forth hereinafter;

        NOW, THEREFORE, this Amendment No. 3 to the Plan is hereby adopted by
the Company with the following effect:

1. Section 2.3 of the Plan is hereby amended so that the such Section 2.3 shall
read in its entirely as follows:

        "Average Earnings" shall mean the average of gross base salary payments
        plus Bonuses as defined in Section 2.7 (except, for a Retired
        Participant receiving a Retirement Benefit as of the Distribution Date,
        Bonuses shall mean gross cash payments of Bonuses) from the Company to
        the Participant in the three twelve consecutive month periods (with no
        overlap), in which such Participant's gross base salary payments plus
        gross Bonuses are the highest, in the Participant's final 120 months of
        employment. For all purposes of calculating "Average Earnings" under
        this Supplemental Plan "gross base salary" shall include (i) any amounts
        deferred pursuant to Section 401(k) or Section 125 of the Code, (ii) any
        amounts deferred at the election of the Participant pursuant to any plan
        of the Company which permits such deferral, and (iii) cash payments,
        during the relevant period, of commissions payable to a Participant as a
        regular part of the Participant's compensation, e.g. to a person engaged
        in sales or marketing; however, commissions not payable as a regular
        part of a Participant's compensation shall not be included in the
        calculation of Average Earnings. Commissions or portions thereof
        otherwise included in the calculation of Average Earnings pursuant to
        the preceding sentence which are deferred (other than at the election of
        a Participant) shall be included in the calculation of Average Earnings
        in the relevant period in which cash payments are made. For purposes of
        calculating Average Earnings under this Supplemental Plan salary
        (including relevant commission payments and bonuses) paid in a non-U.S.
        currency shall be converted to U.S. dollar equivalents using the
        quarterly UNOVA, Inc. official rates of exchange, as determined by the
        Chief Financial Officer and as utilized generally for corporate
        purposes.


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               (a). Average Earnings for purposes of calculating a Disability or
        Death Benefit for or with respect to a Disabled Participant shall be
        calculated using the 120 months that include and precede the month that
        his or her Disability commenced. If a formerly Disabled Participant who
        has returned to active employment with the Company does not have a
        minimum of 36 consecutive calendar months of employment with the Company
        after such return to active employment, then Average Earnings shall be
        calculated by the Committee in accordance with subparagraph (e).


               (b). Average Earnings in the case of an Active Participant who
        dies prior to attaining age 65 shall be calculated using the 120 months
        that include and precede the month of the Participant's death (or
        Disability, in the case of a Disabled Participant who dies). For
        purposes of calculating a lump sum payment pursuant to Section 4.1(d) in
        the event of a Change of Control, with respect to a person (other than a
        Disabled or deceased Participant) who is an Active Participant as of the
        date of such calculation, Average Earnings shall be calculated as if the
        person's employment with the Company ended on such date.

               (c). For purposes of calculating Average Earnings, the
        Participant's gross base salary plus gross Bonuses received while
        employed by Western Atlas (beginning on or after March 17, 1994) or
        Litton (prior to such date), if and to the extent such Western Atlas or
        Litton employment is included within the period of 120 months to be used
        in such calculation, shall be taken into account, provided that the
        Participant's benefits under the Western Atlas retirement plans were
        transferred to the Company pursuant to the Employee Benefits Agreement
        between Western Atlas and UNOVA, Inc.
        (the "Employee Benefits Agreement").

               (d). If a Participant is eligible to receive payments under the
        Supplemental Plan but does not have 36 consecutive months of employment
        with Western Atlas and the Company, then Average Earnings shall be
        calculated by the Committee in accordance with subparagraph (e).

               (e). Notwithstanding the foregoing, the Committee may determine
        Average Earnings for the purposes of this Section by another methodology
        which it determines to be more appropriate under the facts and
        circumstances; provided, however, that, following a Change of Control,
        the authority of the Committee under this subparagraph (e) shall be
        limited to matters referred to in the last sentence of subparagraph (a)
        above and the matters referred to in subparagraph (d) above unless the


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        methodology for determining Average Earnings selected by the Committee
        is more advantageous to the Participant.

2. Except as specifically provided in this Amendment No. 3, each and every
provision of the Plan is hereby ratified, approved, and confirmed.

3. This Amendment No. 3 shall be deemed effective for all purposes on and as of
the date hereof, except that this Amendment No. 3 shall not be effective with
respect to any Participant who retired from the Company subsequent to the
Distribution Date and commenced receiving a Retirement Benefit under the Plan
prior to the date hereof.

4. This Amendment No. 3 shall be governed by the laws of Delaware except to the
extent preempted by ERISA.

5. Capitalized terms used in this Amendment No. 3 and not defined herein shall
have the meaning assigned to such terms in the Plan.

        IN WITNESS HEREOF, the Company has caused this Amendment No. 3 to be
executed by its duly authorized officers this 15th day of March, 2000.


                                         UNOVA, Inc.



WITNESS: /s/ Virginia S. Young           By: /s/ Michael E. Keane
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                                             Michael E. Keane



WITNESS: /s/ Christine McVeigh           By: /s/ Charles A. Cusumano
        -----------------------------       ------------------------------------
                                             Charles A. Cusumano


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