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                         YEAR 2000 UNIONBANCAL CORPORATION
                               MANAGEMENT STOCK PLAN


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               YEAR 2000 UNIONBANCAL CORPORATION MANAGEMENT STOCK PLAN



1.      ESTABLISHMENT, PURPOSE AND DEFINITIONS.


       (a)    This Year 2000 UnionBanCal Corporation Management Stock Plan (the
              "Plan") was adopted by the Board on March 24, 1999, effective upon
              the approval of UNBC's shareholders, to take effect upon the
              expiration of the UnionBanCal Corporation Management Stock Plan
              due to expire on January 1, 2000; provided, however, that the Plan
              is approved within 12 months after March 24, 1999, and on or prior
              to the date of the first annual meeting of UNBC's shareholders
              held subsequent to the acquisition of Common Stock by a
              Participant pursuant to the Plan.  Notwithstanding any provision
              of the Plan or of any Option Agreement to the contrary, no Option
              may be exercisable and no Common Stock may be granted pursuant to
              the Plan prior to such shareholder approval.

       (b)    The purpose of the Plan is to provide a means whereby:

              (i)    Employees may be given an opportunity to purchase shares of
                     Common Stock pursuant to options which may qualify as
                     incentive stock options under Section 422 of the Code
                     (referred to as "incentive stock options");

              (ii)   Employees and Non-Employee Directors, and designated
                     Consultants may be given an opportunity to purchase shares
                     of Common Stock pursuant to options which do not so qualify
                     (referred to as "nonqualified stock options");

              (iii)  Employees and Non-Employee Directors, and designated
                     Consultants may acquire Stock and Stock Appreciation Rights
                     for such consideration (if any) and subject to such
                     restrictions (if any) as the Committee of UNBC determines
                     appropriate.

       (c)    Definitions.

              (i)    AWARD refers collectively to Common Stock grants, Common
                     Stock sales and Options to purchase Common Stock, made
                     pursuant to the Plan.

              (ii)   BOARD refers to UNBC's board of directors.

              (iii)  CODE refers to the Internal Revenue Code of 1986, as
                     amended. Reference in the Plan to any Section of the Code
                     shall be deemed to include any amendments or successor
                     provisions to such Section and any regulations under such
                     Section.

              (iv)   COMMITTEE refers to the Executive Compensation and Benefits
                     Committee of UNBC's Board.




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              (v)    COMMON STOCK refers to the Common Stock of UNBC.

              (vi)   Consultant refers to any person designated by the Committee
                     who is: (I) an independent contractor retained to perform
                     services for UNBC or its Subsidiaries; or (ii) a person who
                     provides services to UNBC or its Subsidiaries pursuant to
                     an agreement between UNBC or its Subsidiaries and any other
                     person or organization, other than Bank of
                     Tokyo-Mitsubishi.

              (vii)  FAIR MARKET VALUE as of any specified date refers to the
                     closing per share price of the Common Stock on the Nasdaq
                     National Market or on any national securities stock
                     exchange on which the Common Stock is traded, as
                     applicable, on that date, or if no price is reported on
                     that date, on the last preceding date on which such price
                     of the Common Stock is reported.

              (viii) EMPLOYEE refers to any common law employee of UNBC or its
                     Subsidiaries except: (1) any independent contractor
                     retained to perform services for UNBC or its Subsidiaries,
                     including consultants; and (2) any person who provides
                     services to UNBC or its Subsidiaries pursuant to an
                     agreement between UNBC or its Subsidiaries and any other
                     person or organization, other than Bank of
                     Tokyo-Mitsubishi.

              (ix)   NON-EMPLOYEE DIRECTOR refers to a member of the Board who
                     is not an Employee.

              (x)    OPTION refers to an Award granted under Section 6 of the
                     Plan and includes both incentive stock options and
                     nonqualified stock options.

              (xi)   OPTION AGREEMENT refers to a written agreement between UNBC
                     and an Employee, Non-Employee Director or Consultant with
                     respect to an Option.

              (xii)  OPTIONEE refers to an Employee, Non-Employee Director or
                     Consultant who has been granted an Option.

              (xiii) OUTSIDE DIRECTOR refers to a member of the Board who
                     qualifies as an "outside director" as such term is used in
                     Section 162(m) of the Code and defined in any applicable
                     Treasury regulations promulgated thereunder, including
                     Treasury regulation 1.162-27(e)(3).  Such member must also
                     qualify as a "non-employee director" under
                     Rule 16b-3(b)(3) of the general Rules and Regulations of
                     the Securities and Exchange Commission under the Securities
                     Exchange Act of 1934, as amended.

              (xiv)  PARTICIPANT refers to a recipient of an Award.

              (xv)   SUBSIDIARIES refers to subsidiary corporations, as defined
                     in Section 424(f) of the Code (but substituting "UNBC" for
                     "employer corporation"), including Subsidiaries of UNBC
                     which become such after the adoption of the Plan.


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2.      ADMINISTRATION OF THE PLAN.


       (a)    The Plan shall be administered by the Committee, which shall be
              composed as hereinafter set forth in Section 2(b).

       (b)    The Committee shall consist solely of not less than two Outside
              Directors elected by the Board. The Board may from time to time
              increase (and thereafter may decrease) the size of the Committee,
              elect or remove members thereto (with or without cause) and fill
              any vacancies however created; provided, however, that the minimum
              number of members on the Committee must be two.

       (c)    The Committee shall meet at such times and places and upon such
              notice as the Committee's Chair determines. A majority of the
              Committee shall constitute a quorum. Any acts by the Committee may
              be taken at any meeting at which a quorum is present and shall be
              by majority vote of those members entitled to vote.

       (d)    The Committee shall determine which Employees, Non-Employee
              Directors, or Consultants of UNBC or its Subsidiaries shall be
              granted Awards under the Plan, the timing of such Awards, the
              terms thereof and the number of shares of Common Stock subject to
              each Award.

       (e)    The Committee shall have the sole authority, in its absolute
              discretion, to adopt, amend and rescind such rules and regulations
              as, in its opinion, may be advisable in the administration of the
              Plan, to construe and interpret the Plan, its rules and
              regulations, and the instruments evidencing Awards granted under
              the Plan, and to make all other determinations deemed necessary or
              advisable for the administration of the Plan.  All decisions,
              determinations and interpretations of the Committee shall be
              binding on all Participants.

3.      STOCK SUBJECT TO THE PLAN.


       (a)    Awards may be granted under the Plan to eligible persons for an
              aggregate of not more than 10,000,000 shares of Common Stock.  If
              an Option is surrendered for cash or other consideration or for
              any other reason ceases to be exercisable in whole or in part, the
              shares of Common Stock which were subject to such Option but as to
              which the Option had not been exercised shall continue to be
              available under the Plan. If Common Stock is granted or sold
              subject to restrictions and is subsequently forfeited, the
              forfeited shares shall again be available for Awards under the
              Plan.


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       (b)    If there is any change in the Common Stock subject to the Plan or
              the Common Stock subject to any Award granted under the Plan,
              through merger, consolidation, reorganization, recapitalization,
              reincorporation, stock split, stock dividend, or other change in
              the corporate structure of UNBC, the Board and the Committee shall
              make appropriate adjustments in order to preserve but not to
              increase the benefits to the Participants, including adjustments
              in the aggregate number of shares of Common Stock subject to the
              Plan and the number of shares of Common Stock and the Fair Market
              Value subject to outstanding Awards.

4.     ELIGIBILITY.  Persons who shall be eligible to have Awards granted to
       them shall be such Employees, Non-Employee Directors, and Consultants as
       the Committee, in its discretion, shall designate from time to time. Only
       Employees shall be eligible to receive incentive stock options.

5.     OPTION EXERCISE PRICE.  The exercise price of the Common Stock covered by
       each Option shall not be less than the Fair Market Value of such Common
       Stock on the date the Option is granted. Notwithstanding the foregoing,
       in the case of an incentive stock option granted to a person possessing
       more than 10% of the combined voting power of UNBC or its Subsidiaries,
       the exercise price shall not be less than 110% of the Fair Market Value
       of the Common Stock on the date the Option is granted. The exercise price
       of an Option shall be subject to adjustment to the extent provided in
       Section 3(b), above.

6.     TERMS AND CONDITIONS OF OPTIONS.


       (a)    Each Option granted pursuant to the Plan shall be evidenced by an
              Option Agreement executed by the Union Bank of California, N.A.
              ("UBOC") Director of Human Resources or his or her designee and
              the person to whom such option is granted.

       (b)    The Committee shall determine the term of each Option granted
              under the Plan, but the term of each Option shall be for no more
              than ten years; provided, however, that in the case of an Option
              granted to a person possessing more than 10% of the combined
              voting power of UNBC or its Subsidiaries, the term of each
              incentive stock option shall be for no more than five years.

       (c)    In the case of incentive stock options, the aggregate Fair Market
              Value (determined as of the time such option is granted) of the
              Common Stock with respect to which incentive stock options are
              exercisable for the first time by the Optionee in any calendar
              year (under the Plan and any other plans of UNBC or its
              Subsidiaries) shall not exceed $100,000.

       (d)    An Option Agreement may contain such other terms, provisions and
              conditions as may be determined by the Committee (not inconsistent
              with the Plan), including, without limitation, stock appreciation
              rights pursuant to Section 7 of the Plan with respect to Options
              granted under the Plan. If an Option, or any part thereof, is
              intended to qualify as an incentive stock option, the Option
              Agreement shall contain those terms and conditions which are
              necessary to so qualify it as required by Section 422 of the Code
              and any applicable Treasury Regulations promulgated thereunder.


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       (e)    Each incentive stock option granted pursuant to the Plan shall,
              during the Optionee's lifetime, be exercisable only by him, and
              neither the incentive stock option nor any right hereunder shall
              be transferable by the Optionee by operation of law or otherwise
              other than by will or the laws of descent and distribution. The
              transferability of a nonqualified stock option will be established
              in the Option Agreement to be entered into between UNBC and the
              Optionee.

       (f)    The maximum number of shares of Common Stock with respect to which
              the Committee may make Awards during any calendar year to any
              Employee, any Non-Employee Director, or any Consultant shall not
              exceed 300,000.

7.     STOCK APPRECIATION RIGHTS.  The Committee may, under such terms and
       conditions as it deems appropriate, authorize the surrender by an
       Optionee of all or part of an unexercised Option and authorize a payment
       in consideration therefor in an amount equal to the difference obtained
       by subtracting the Option exercise price of the shares then subject to
       exercise under such Option from the Fair Market Value of the Common Stock
       represented by such shares on the date of surrender, provided that the
       Committee determines that such settlement is consistent with the purpose
       of the Plan. Such payment may be made in shares of Common Stock valued at
       their Fair Market Value on the date of surrender of such Option or in
       cash, or partly in shares and partly in cash. Acceptance of surrender and
       the manner of payment shall be in the discretion of the Committee. Any
       payments of cash under this Section shall be from the general assets of
       UNBC. Notwithstanding anything to the contrary herein, the maximum number
       of shares of Common Stock with respect to which the Committee may award
       stock appreciation rights during any calendar year to any Employee, any
       Non-Employee Director, or any Consultant shall not exceed 300,000.

8.     COMMON STOCK GRANTS AND COMMON STOCK SALES.  The Committee may, in its
       discretion, issue Common Stock, with or without consideration, to
       eligible persons as compensation for services rendered to UNBC or its
       Subsidiaries, on whatever basis and subject to such terms and conditions
       as the Committee determines. The terms and conditions of such an Award
       shall be evidenced by a written agreement executed by UNBC and the
       Participant.

9.     RESTRICTIONS ON TRANSFER OF COMMON STOCK.  Common Stock acquired under
       the Plan shall be subject to such restrictions and agreements regarding
       vesting, sale, assignment, encumbrance or other transfer as the Committee
       deems appropriate at the time of making an Award; subject, however, to
       compliance with applicable state and federal laws.

10.    USE OF PROCEEDS.  Any cash proceeds realized from the sale of Common
       Stock pursuant to the Plan or from the exercise of Options granted under
       the Plan shall constitute general funds of UNBC.


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11.    AMENDMENT, SUSPENSION OR TERMINATION OF THE PLAN.

       (a)    The Board may at any time amend, suspend or terminate the Plan as
              it deems advisable; provided, however, except as provided in
              Section 3(b), above, the Board shall not amend the Plan in the
              following respects without the consent of UNBC's shareholders then
              sufficient to approve the Plan in the first instance:

              (i)    to increase the maximum number of shares of Common Stock
                     subject to the Plan; or

              (ii)   to change the designation or class of persons eligible to
                     receive Awards under the Plan.

       (b)    No Award may be granted during any suspension or after the
              termination of the Plan, and no amendment, suspension or
              termination of the Plan shall, without the Participant's consent,
              alter or impair any rights or obligations under any Award
              previously made under the Plan.

       (c)    The Plan shall terminate ten years from the original effective
              date of the Plan, unless previously terminated by the Board
              pursuant to this Section 11.

       (d)    Upon a termination of the Plan, UNBC or the Committee may
              authorize the surrender by an Optionee of all or part of an
              unexercised Option and authorize a payment in consideration
              therefor in the same manner as if the Participant had surrendered
              an Option under Section 7 regarding stock appreciation rights. The
              payment received by the Optionee pursuant to this Section
              11(d) shall not be considered remuneration for services performed
              by the Optionee under Section 162(m) of the Code.

12.    CONSIDERATION.  Payment of the exercise price of an Option or payment of
       any consideration required for an Award granted under the Plan shall be
       made in cash; provided, however, that the Committee, in its sole
       discretion, may permit a Participant to pay the exercise or purchase
       price in whole or in part by (a) delivery (on a form prescribed by the
       Committee) of an irrevocable direction to a securities broker or brokers
       approved by the UBOC Director of Human Resources or his or her designee
       to sell shares and deliver all or a portion of the proceeds to UNBC in
       payment for the Common Stock, or (b) Common Stock.  For purposes of
       determining the amount of exercise price or purchase price satisfied by
       payment of Common Stock, such Common Stock shall be valued at its Fair
       Market Value as of the date of exercise of Option or purchase of Award,
       whichever is applicable.


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13.    PERFORMANCE-BASED COMPENSATION.  The Plan shall be interpreted to be in
       compliance with requirements under Section 162(m) of the Code and all
       applicable Treasury Regulations promulgated thereunder so that grants of
       Options or Stock Appreciation Rights under the Plan will be treated as
       "Performance-Based Compensation" as such term is used in Section
       162(m)(4)(C) of the Code.  To the extent that any provision in the Plan
       would cause the Options or Stock Appreciation Rights not to be treated as
       "Performance-Based Compensation" under Section 162(m)(4)(C) of the Code,
       such provision will be stricken from the Plan, and the remaining
       provisions shall nevertheless continue in full force and effect without
       being impaired or invalidated.

14.    GOVERNING LAW.  The Plan will be administered in accordance with the laws
       of the State of California and all applicable federal law.

       IN WITNESS WHEREOF, the undersigned have executed the Year 2000
UnionBanCal Corporation Management Stock Plan, at San Francisco, California, on
this May 26, 1999.

                                   UNIONBANCAL CORPORATION



                                   By:         /s/ Takahiro Moriguchi
                                       ---------------------------------------
                                                  Takahiro Moriguchi
                                        PRESIDENT AND CHIEF EXECUTIVE OFFICER






                                   By:           /s/ Paul E. Fearer
                                       ---------------------------------------
                                                    Paul E. Fearer
                                             DIRECTOR OF HUMAN RESOURCES

Date Approved By Executive Compensation and Benefits Committee: February 24,
1999

Date Adopted By UnionBanCal Corporation Board of Directors: March 24, 1999

Date Approved By Shareholders: May 26, 1999

Effective Date: January 1, 2000


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