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                           UNION BANK OF CALIFORNIA

                               SENIOR MANAGEMENT
                                  BONUS PLAN


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                        -- EFFECTIVE JANUARY 1, 1999 --

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                           UNION BANK OF CALIFORNIA
                         SENIOR MANAGEMENT BONUS PLAN


I.     OBJECTIVE

       Union Bank of California (the Bank) provides a challenging and rewarding
       environment where outstanding performance is encouraged and recognized.
       Senior Managers are provided with a base salary and the opportunity to
       earn additional compensation based on, and consistent with, their
       individual performance.

       The objective of the Senior Management Bonus Plan (the Plan) is to reward
       Senior managers who assist in achieving and exceeding the Bank's and
       their Group's financial goals. In addition, the Plan is designed to help
       provide an environment that stimulates high performance, as well as
       motivates Senior Managers to exercise initiative, effort, and ingenuity.

II.    EFFECTIVE DATE

       The Plan is effective as of January 1, 1999.

III.   ELIGIBILITY

       With the exception of policy-making officers who are Bank Of
       Tokyo-Mitsubishi (BTM) expatriates and the Chairman, the following
       individuals are eligible to participate in the Plan:

-      Vice Chairmen and policy-making EVP's.

-      Other Executive Vice Presidents (EVP) and Senior Vice Presidents (SVP)
       whose focus and impact are on overall Bank performance and do not
       participate in business unit incentive plans.

IV.    BASIS FOR PAYMENT

       A.  BANK FINANCIAL GOALS

           The Bank's Plan goals for Return On Average Common Shareholders
           Equity Ratio and goal for Net Income will be designated by the
           President and CEO in the financial planning process, as follows:

           ---------------------------------------------------------------------

               NORMALIZED RETURN ON                    NORMALIZED NET INCOME
                  AVERAGE COMMON                          AVERAGE COMMON
                   SHAREHOLDERS             =              SHAREHOLDERS
                      EQUITY                                  EQUITY

           ---------------------------------------------------------------------


                                       2

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B.     INCENTIVE TARGETS

       Incentive targets with Bank performance at 100% of financial goals are
       30% for SVP's, 45% for EVPs, and 60% for Vice Chairmen.

       Group Heads may recommend individual incentive targets that vary by
       position within officer level, taking into consideration competitive
       market factors and the criticality of the position. Variances in
       individual incentive targets and resulting payments are subject to review
       and approval of the President and CEO, provided that the payments do not
       exceed the approved bonus fund designated for the respective officer
       level for each Group.

C.     FUNDING FORMULA

       The size of the bonus pool will be based on the Bank's performance
       against budgeted ROE and Net Income as follows:

              BONUS INCENTIVE PAYOUT MATRIX
              (% OF TARGET PAYOUT)

<TABLE>
<CAPTION>

                                 ---------------
                                   NET INCOME
                                 ------------------------------------------------------------------------------
                                                                                                        > OR =
                                 < 75%       75%       80%       90%      100%       110%      120%     TO 125%
         <S>        <C>          <C>         <C>       <C>      <C>       <C>        <C>       <C>      <C>
         ------------------------------------------------------------------------------------------------------
         RETURN       < 80%         0%        0%        5%       15%       25%        35%       45%         50%
           ON
         EQUITY
         ------------------------------------------------------------------------------------------------------
                        80%         0%       25%       30%       40%       50%        60%       70%         75%
                    -------------------------------------------------------------------------------------------
                        90%        13%       38%       45%       60%       75%        90%      105%        113%
                    -------------------------------------------------------------------------------------------
                       100%        25%       50%       60%       80%      100%       120%      140%        150%
                    -------------------------------------------------------------------------------------------
                       110%        37%       63%       75%      100%      125%       145%      165%        175%
                    -------------------------------------------------------------------------------------------
                    > OR = TO
                       120%        50%       75%       90%      120%      150%       170%      190%        200%
                    -------------------------------------------------------------------------------------------

</TABLE>

       -      The bonus pool may then be modified by up to +/- 20% of target
              according to other performance considerations by the Committee.

       -      For purposes of interpolating between performance levels,
              additional discrete performance levels may be added between the
              minimum and maximum for each performance factor.

       The President and CEO, in consultation with the CFO, will submit bonus
       fund recommendations to the Committee, which may modify the fund by
       +/- 20% of target


                                       3

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       (but in no event may the fund exceed two (2) times the target) based on
       such factors as:

       -      The Bank's overall performance in relation to other peer banks;

       -      Whether absolute Return On Equity and/or Net Income goals are
              reasonable in relation to long-term objectives and the Bank's
              historical performance;

       -      Efficiency ratios as compared to peer banks, with recognition that
              constant attention must be given to long-term expense reduction
              through continuous productivity improvement in order to support
              UBOC's competitiveness;

       -      Effectiveness of risk management;

       -      General economic or market conditions;

       -      Achievement of other financial and strategic objectives;

       -      Normalizing financial data to allow for an acquisition/merger,
              other extraordinary circumstances or material events that were not
              specifically planned or not directly related to the performance of
              Bank executives during the performance year.


                                       4

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D.       BONUS POOL ALLOCATION

         The pool will be allocated based on corporate and unit/individual
         performance as follows:






                                   [GRAPHIC]






                                       5

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E.       DETERMINING INDIVIDUAL AWARDS

         1.  Individual bonus awards will be based on performance criteria
             established at the beginning of the year and are determined in
             the following manner:

             a.  The President and CEO will recommend awards for eligible
                 Vice Chairmen and policy-making officers to the Committee,
                 which will then review and approve these awards, with or
                 without modification.

             b.  The President and CEO will allocate the remaining funds
                 for non-policy-making officers to Group Heads based on
                 aggregate individual incentive award targets and Group
                 performance. Any adjustments to allocations, based on
                 Group performance, must be made within the approved
                 bonus funding limits. The President and CEO will also
                 issue guidelines for Group Heads to develop individual
                 bonus award recommendations.

             c.  Group Heads will submit individual EVP and eligible SVP
                 bonus award recommendations for review and approval by
                 the President and CEO.

             d.  The Committee may request a report on bonuses awarded to
                 executives other than policy-making officers.

         2.      Individual awards may range from zero (0) times to two
                 (2) times target awards.

         3.      Vacation, sick pay, and all other employee benefit plans
                 excluding the 401(k) plan and retirement are based on the base
                 salary rate and do not include Senior Management Bonus
                 payments.

V.     ADMINISTRATION

       A.  The final authority and responsibility for administration of the
           Plan resides exclusively with the Committee.

       B.  The Chief Financial Officer will have responsibility for
           calculating the bonus funds including the application of any fund
           limitations specified by the Committee. The bonus funds will be
           rounded to the nearest thousand dollars and individual awards will
           be rounded to the nearest one hundred dollars.

       C.  The Director of Human Resources will have responsibility for
           providing the Chief Financial Officer with information on
           bonus-eligible executives and salaries, processing award payments,
           and keeping records of activities related to the Plan.


                                       6

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       D.  Participants must be employed by the Bank, Bank of Tokyo-Mitsubishi
           Group or a subsidiary or affiliate through the end of the performance
           year in order to receive payment. In the case of retirement, death,
           permanent disability, or exceptional circumstances, deviations from
           eligibility may be approved at the sole discretion of the President
           and CEO for non-policy making EVPs and eligible SVP's and at the sole
           discretion of the Committee for policy-making officers.

       E.  The award payments will be made as soon as administratively practical
           after the end of the fiscal year.

VI.    STAFF CHANGES

       A.  New employees will be eligible to participate in the Plan
           immediately. Awards may be prorated based on the time in the Plan
           and the contribution of the participant.

       B.  Plan participants who are transferred to another Bank position not
           covered by this Plan or who are on Leave of Absence during the
           year will be eligible for an award that will be calculated on a
           prorated basis. Incentive payments will be calculated according to
           the provisions described in this Plan and paid on the established
           schedule for other Plan participants.

VII.   GENERAL PROVISIONS

       A.  NO CONTRACT OF EMPLOYMENT
           Neither the actions of the Bank in establishing this Plan or its
           provisions, nor any action taken according to those provisions,
           will be construed as giving the right to a participant to continue
           in the employ of the Bank. The Plan is not a contract of
           employment. No rights in the Plan will accrue to any person
           whether or not he/she is selected to participate in the Plan, and
           no person will, because of the Plan acquire any right to an
           accounting or to examine the books or the affairs of the Bank.

       B.  ASSIGNMENT
           No funds, assets or other property of the Bank, and no obligation
           or liability of the Bank under this Plan, will be subject to any
           claim of any participant, nor will any participant have any right
           or power to pledge, encumber or assign any incentive award
           provided for in the Plan.


                                       7

<PAGE>

       C.  SOLE AND ENTIRE PLAN
           No Bank director, officer, employee or other person has the
           authority to enter into any agreement, either written or oral,
           with any person or participant concerning an award or payment of
           an incentive award, or to make any representation or warranty with
           respect to any incentive award under this plan. Only the Director
           of Human Resources with the written concurrence of the Chief
           Executive Officer will have such authority. This Plan supersedes
           any prior oral or written understanding on this subject.

       D.  CONTINGENCY
           The Plan is contingent in character and, therefore, no rights will
           vest in any individual participant under the Plan until all
           conditions of the Plan are satisfied.

       E.  MINIMUM PERSONAL PERFORMANCE
           Bank management in its absolute discretion retains the right to
           reduce or eliminate incentive awards which are not yet paid for a
           participant whose personal performance level is unsatisfactory,
           regardless of the Bank's or Group's performance. Unsatisfactory
           personal performance shall be determined by the Bank in its
           absolute discretion and may include, but only as examples and not
           as an exhaustive list, such factors as misconduct, poor
           performance appraisal rating, poor credit management, poor account
           management, disruptive behavior, failure to adhere to Bank
           policies and procedures, failure to abide by Bank compliance
           standards, poor audits, failure to control or monitor risk, or
           other relevant factors.

       F.  NO VESTING
           The right to receive any payment of an incentive award shall not
           vest in any employee, or the estate of the employee, until such
           payment is actually made in accordance with the terms and
           conditions of the Plan.

       G.  ADMINISTRATION
           Bank management shall determine in its absolute discretion all
           elements and goals of the Plan. All determinations made by the
           Bank shall be binding. At any time prior to the date the awards
           are paid, the Bank reserves the right to adjust any elements or
           goals of the Plan.

       H.  AMENDMENT
           Bank management may at any time, revise, amend, suspend, or
           terminate in whole or in part, any or all provisions of this Plan.

       I.  OTHER INCENTIVE PLANS
           An individual may not participate in this Plan if he/she is
           participating in any business unit incentive plan.


                                       8

<PAGE>

       J.  TAX RELATED LIABILITIES
           Participants are responsible for determining the tax consequences
           of incentive awards and arranging for appropriate withholding and
           payment of all taxes due. The Bank will not be responsible for and
           will be held harmless from liability for payments, interest,
           penalties, costs or expenses incurred as a result of not arranging
           for sufficient withholding or deductions from incentive awards.

       K.  ARBITRATION
           This Plan is made, and shall in all respects be interpreted,
           enforced and governed by and under the laws of the United States,
           as appropriate, and the State of California. Any dispute arising
           out of or relating to this Plan including its meaning or
           interpretation will be resolved solely by arbitration before an
           experienced employment arbitrator selected in accordance with the
           model employment arbitration procedures of the American
           Arbitration Association. The locations of the arbitration will be
           in San Francisco, Los Angeles or San Diego as selected by the Bank
           in good faith. The provisions of this paragraph are exclusive for
           all purposes and applicable to any and all disputes between a
           participant and the Plan. Any decision or award by an arbitrator
           shall affect the Plan solely as to its obligations to the
           participant who requests arbitration. The arbitrator's decision
           will have no impact on the Plan's relationship to any other
           participant, nor will it require the Bank to interpret the Plan in
           any particular manner.

       L.  EXCEPTIONS
           Bank management recognizes that occasionally unique or unusual
           circumstances including, but not limited to, internal
           reorganizations, dual responsibilities or special and
           extraordinary efforts by participants will arise that may require
           consideration of exceptions to Plan provisions. Accordingly, on a
           case-by-case basis, exceptions to any provision in this incentive
           plan may be made with the recommendation and approval of the Group
           Head, the Director of Human Resources and the Chief Executive
           Officer or his designee. The Committee has the sole discretion to
           approve exceptions applicable to policy-making officers. This
           approval may be sought at the time incentive payments are
           submitted for approval. Any approved exceptions will affect the
           Plan solely as to the participant involved and will have no impact
           on other Bank employees or participants in the Plan.

       M.  FORM AND TIMING OR PAYMENT
           Incentive awards will be paid in cash, less applicable employment
           taxes and federal, state and foreign withholding taxes. Incentive
           awards will be calculated and paid as provided in the Plan. In
           order to induce continued employment with the Bank, however,
           participants must be actively employed by the Bank on the last day
           of the performance period in order to be paid the incentive award.
           Thus, participants who terminate before the end of the performance
           period shall forfeit such award. Nevertheless, based on the Bank's
           absolute discretion, participants whose employment is terminated
           during the performance period due to death, disability,


                                       9

<PAGE>

           retirement or as a result of an organizational structure,
           office/unit closure or reduction in force may receive a prorated
           award. Such awards will be calculated and paid according to the
           normal procedures set forth in the Plan. All awards paid shall be
           final.

       N.  BENEFITS UNFUNDED AND UNSECURED
           The rights of a participant, or any designated beneficiary of the
           participant, shall be solely those of an unsecured general
           creditor of the Bank, and the Bank's obligation shall be an
           unfunded and unsecured promise to pay.


                                       10