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                             NATIONAL MERCANTILE BANCORP

                          AMENDED 1996 STOCK INCENTIVE PLAN



     Section 1.  PURPOSE

     The purpose of the 1996 Stock Incentive Plan (the "1996 Plan") of National
Mercantile Bancorp, a California corporation and a registered bank holding
company under the Bank Holding Company Act of 1956, as amended (the "Company"),
is to enable the Company to attract, retain and motivate its employees and
independent contractors by providing for or increasing the proprietary interests
of such employees and independent contractors in the Company, and to enable the
Company to attract, retain and motivate its nonemployee directors and further
align their interest with those of the shareholders of the Company by providing
for or increasing the proprietary interest of such directors in the Company.


     2.   PERSONS ELIGIBLE

     Each director, officer, employee or independent contractor of the Company
or any of its subsidiaries (each, a "Participant") shall be eligible to be
considered for the grant of an Award (as hereinafter defined) under the 1996
Plan.  Directors who are not employees ("Nonemployee Directors") may receive
awards in addition to those described under Section 10 of the 1996 Plan.


     3.   AWARDS

     (a)  The Committee (as hereinafter defined) responsible for administration
of the 1996 Plan is authorized to enter into any type of arrangement on behalf
of the Company with a Participant that is not inconsistent with the provisions
of the 1996 Plan and that, by its terms, involves or might involve the issuance
of (i) shares of common stock of the Company ("Common Shares") or (ii)
Derivative Security (as such term is defined in Rule 16a-1 promulgated under the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), as such rule
may be amended from time to time) with an exercise or conversion privilege at a
price related to the Common Shares or with a value derived from the value of the
Common Shares. The entering into of any such arrangement is referred to herein
as the grant of an "Award."

     (b)  Awards are not restricted to any specified form or structure and may
include, without limitation, sales or bonuses of stock, restricted stock, stock
options, reload stock options, stock purchase warrants, other rights to acquire
stock, securities convertible into or redeemable for stock, stock appreciation
rights, phantom stock, dividend equivalents, performance units or 

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performance shares, and an Award may consist of one such security or benefit, 
or two or more of them in tandem or in the alternative.

     (c)  Awards may be issued, and Common Shares may be issued pursuant to an
Award, for any lawful consideration as determined by the Committee, including,
without limitation, services rendered by the recipient of such Award.

     (d)  Subject to the provisions of the 1996 Plan, the Committee, in its sole
and absolute discretion, shall determine all of the terms and conditions of each
Award granted hereunder, which terms and conditions may include, among other
things:

               (i)   a provision permitting the recipient of such Award,
          including any recipient who is a director or officer of the Company,
          to pay the purchase price of the Common Shares or other property
          issuable pursuant to such Award, or such recipient's tax withholding
          obligation with respect to such issuance, in whole or in part, by any
          one or more of the following:

               (A)   the delivery of cash;

               (B)   the delivery of other property deemed acceptable by the
                     Committee;

               (C)   the delivery of previously owned shares of capital stock of
                     the Company (including "pyramiding"); or

               (D)   a reduction in the amount of Common Shares or other
                     property otherwise issuable pursuant to such Award.

               (ii)  a provision conditioning or accelerating the receipt of
          benefits pursuant to such Award, either automatically or in the
          discretion of the Committee, upon the occurrence of specified events,
          including, without limitation, a change of control of the Company (as
          defined by the Committee), an acquisition of a specified percentage of
          the voting power of the Company, the dissolution or liquidation of the
          Company, a sale of substantially all of the property and assets of the
          Company or an event of the type described in Section 7 hereof; or

               (iii) a provision required in order for such Award to qualify as
          an incentive stock option (an "Incentive Stock Option") under Section
          422 of the Internal Revenue Code of 1986, as amended (the "Code");
          provided, however, that no Award issued to any Nonemployee Director or
          any independent contractor of the Company shall qualify as an
          Incentive Stock Option.


     Section 4.  STOCK SUBJECT TO THE 1996 PLAN


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     (a)  At any time, the aggregate number of Common Shares issued or issuable
pursuant to all Awards (including all Incentive Stock Options) granted under the
1996 Plan shall not exceed 348,510 shares subject to adjustment as provided in
Section 7 hereof.

     (b)  For purposes of Section 4(a) hereof, the aggregate number of Common
Shares issued or issuable pursuant to Awards granted under the 1996 Plan shall
at any time be deemed to be equal to the sum of the following:

               (i)   the number of Common Shares that were issued prior to such
          time pursuant to Awards granted under the 1996 Plan, other than Common
          Shares that were subsequently reacquired by the Company pursuant to
          the terms and conditions of such Awards and with respect to which the
          holder thereof received no benefits of ownership such as dividends;
          plus

               (ii)  the number of Common Shares that were otherwise issuable
          prior to such time pursuant to Awards granted under the 1996 Plan, but
          that were withheld by the Company as payment of the purchase price of
          the Common Shares issued pursuant to such Awards or as payment of the
          recipient's tax withholding obligation with respect to such issuance;
          plus

               (iii) the maximum number of Common Shares that are or may be
          issuable at or after such time pursuant to Awards granted under the
          1996 Plan prior to such time.


     Section 5.      DURATION

     Unless sooner terminated pursuant to Section 8 below, the 1996 Plan shall
terminate on March 28, 2006.  No Awards shall be granted under the 1996 Plan
while the 1996 Plan is suspended or after it is terminated.


     Section 6.      ADMINISTRATION

     (a)  The 1996 Plan shall be administered by a committee (the "Committee")
of the Board of Directors of the Company (the "Board") consisting of two or more
directors, each of whom:  (i) is a "disinterested person" (as such term is
defined in Rule 16b-3 promulgated under the Exchange Act, as such Rule may be
amended from time to time); and (ii) is an "outside director" within the meaning
of Section 162(m) of the Code.  Members of the Committee shall serve at the
pleasure of the Board, and the Board may from time to time remove members from
or add members to, the Committee.

     (b)  Subject to the provisions of the 1996 Plan, the Committee shall be
authorized and 

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empowered to do all things necessary or desirable in connection with the 
administration of the 1996 Plan, including, without limitation, the following:

               (i)   adopt, amend and rescind rules and regulations relating to
          the 1996 Plan;

               (ii)  determine which persons are Participants and to which of
          such Participants, if any, Awards shall be granted hereunder;

               (iii) grant Awards to Participants and determine the terms and
          conditions thereof, including the number of Common Shares issuable
          pursuant thereto;

               (iv)  determine the terms and conditions of the Nonemployee
          Director Options that are automatically granted hereunder, other than
          the terms and conditions specified in Section 10 hereof;

               (v)   determine whether, and the extent to which adjustments are
          required pursuant to Section 7 hereof; and

               (vi)  interpret and construe the 1996 Plan and the terms and
          conditions of any Award granted hereunder.


     Section 7.      ADJUSTMENTS

     If the outstanding shares of the class of Company stock then subject to the
1996 Plan are increased, decreased or exchanged for or converted into cash,
property or a different number or kind of securities, or if cash, property or
securities are distributed in respect of such outstanding securities, in either
case as a result of a reorganization, merger, consolidation, recapitalization,
restructuring, reclassification, dividend (other than a regular cash dividend)
or other distribution, stock split, reverse stock split or the like, or if
substantially all of the property and assets of the Company are sold, then,
unless the terms of such transaction shall provide otherwise, the Committee
shall make appropriate and proportionate adjustments in:  (i) the number and
type of shares or other securities or cash or other property that may be
acquired pursuant to Awards theretofore granted under the 1996 Plan; and (ii)
the maximum number and type of shares or other securities that may be issued
pursuant to Awards thereafter granted under the 1996 Plan.  The determination of
the Committee as to what adjustments shall be made pursuant to this section, and
the extent thereof, shall be final and conclusive.  No fractional shares of
stock shall be issued under the 1996 Plan on account of any such adjustment.


     Section 8.      AMENDMENT AND TERMINATION

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     The Board may suspend or terminate the 1996 Plan at any time; provided,
however, that no such suspension or termination shall deprive the recipient of
any Award theretofore granted under the 1996 Plan, without the consent of such
recipient, of any of his or her rights thereunder or with respect thereto.

     The Board may amend the 1996 Plan at any time and in any manner subject to
the following limitations:

     (a)  No such amendment shall deprive the recipient of any Award theretofore
granted under the 1996 Plan, without the consent of such recipient, of any of
his or her rights thereunder or with respect thereto;

     (b)  Except as otherwise provided in Section 7 relating to adjustments upon
changes in stock, no such amendment shall be effective unless approved by the
affirmative vote of the holders of a majority of the outstanding shares of the
Company present, represented and entitled to vote at a shareholders meeting or
by the written consent of a majority of the outstanding shares of the Company
where such shareholder approval is required by law or pursuant to the Articles
of Incorporation or Bylaws of the Company; and

     (c)  Section 10 hereof shall not be amended more than once every six (6)
months, other than to comport with changes in the Code, the Employee Retirement
Income Security Act, or the rules and regulations thereunder.


     Section 9.      EFFECTIVE DATE

     The 1996 Plan shall be effective as of June 18, 1997, the date upon which
it was approved by the shareholders of the Company; provided, however, that no
Common Shares may be issued under this Plan until it has been approved, director
or indirectly, by the affirmative vote of the holders (the "Shareholders") of a
majority of the outstanding shares of the Company present, or represented, and
entitled to vote at a meeting duly held in accordance with the laws of the State
of California.


     Section 10.     NONEMPLOYEE DIRECTOR OPTIONS

     (a)  Any person elected or appointed to serve as a Nonemployee Director who
has not previously served as a Nonemployee Director of the Company on or prior
to October 1, 1996, shall be granted, on the first business day following the
later of the date of such election or appointment or the date the 1996 Plan is
approved by the Shareholders, an option to purchase 1,100 Common Shares without
the requirement of any further action by the Committee.  On the first business
day following the date of the annual meeting of shareholders of the Company held
in 1998, or any adjournment thereof (the "1998 Meeting"), any person who was a
Nonemployee 

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Director on or after the effective date of the 1996 Plan and who is 
re-elected to the Board at the 1998 Meeting shall be granted an option to 
purchase 550 Common Shares without the requirement of any further action by 
the Committee.  Options that may be granted to newly-elected Nonemployee 
Directors or to re-elected Nonemployee Directors under this Section 10 shall 
be referred to collectively as the "Nonemployee Director Options."  The date 
on which a Nonemployee Director Option is granted shall be the Date of Grant 
for such option.

     (b)  If, on any date upon which Nonemployee Director Options are to be
automatically granted pursuant to this Section 10, the number of Common Shares
remaining available for options under the 1996 Plan is insufficient for the
grant to each Nonemployee Director entitled thereto of a Nonemployee Director
Option to purchase the entire number of Common Shares specified in this Section
10, then a Nonemployee Director Option to purchase a proportionate amount of
such available number of Common Shares (rounded to the nearest whole share)
shall be granted to each Nonemployee Director entitled thereto on such date.

     (c)  Each Nonemployee Director Option granted under the 1996 Plan shall
become fully exercisable one year from the Date of Grant, provided that in the
event that a Change of Control (as defined below) shall occur, such granted
Nonemployee Director Option shall be immediately exercisable.

     (d)  Each Nonemployee Director Option granted under the 1996 Plan shall
expire upon the sixth anniversary of the Date of Grant.

     (e)  Each Nonemployee Director Option shall have an exercise price equal to
the aggregate Fair Market Value on the Date of Grant of the Common Shares
subject thereto.

     (f)  Payment of the exercise price of any Nonemployee Director Option
granted under the 1996 Plan shall be made in full in cash concurrently with the
exercise of such option; provided however, that, in the discretion of the Board,
the payment of such exercise price may instead be made:

               (i)   in whole or in part, with Common Shares delivered
          concurrently with such exercise (such shares to be valued on the basis
          of the Fair Market Value of such shares on the date of such exercise),
          provided that the Company is not then prohibited from purchasing or
          acquiring Common Shares; or

               (ii)  in whole or in part, by the delivery, concurrently with
          such exercise and in accordance with Section 220.3(e)(4) of Regulation
          T promulgated under the Exchange Act, of a properly executed exercise
          notice for such option and irrevocable instructions to a broker
          promptly to deliver to the Company a specified dollar amount of the
          proceeds of a sale of or a loan secured by the Common Shares issuable
          upon exercise of such option.

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     (g)  For purposes of this Section 10, the "Fair Market Value" of a Common
Share or other security on any date (the "Determination Date") shall be equal to
the average of the high bid and low asked prices per Common Share or unit of
such other security on the business day immediately preceding the Determination
Date in the market where the security is traded, or, if the Common shares or
such other security were not quoted by any such organization on such immediately
preceding business day, as determined by the Board.  for purposes of this
Section 10, the term "Change of Control" shall mean the occurrence of either of
the following events:  (a) the Company consolidates with or merges with or into
any person or conveys, transfers or leases all or substantially all of its
assets to any person, or any corporation consolidates with or merges into or
with the Company in any event pursuant to a transaction in which the outstanding
voting stock or units of the Company is changed into or exchanged for cash,
securities or other property, other than any such transaction where the
outstanding voting stock or units of the Company is not changed or exchanged at
all (except to the extent necessary to reflect a change in the jurisdiction of
incorporation or organization of the Company) or where the outstanding voting
stock or units of the Company is changed into or exchanged for voting stock or
units of the surviving corporation or organization which is not redeemable, or
no "person" or "group" owns immediately after such transaction, directly or
indirectly, an amount of outstanding voting stock or units necessary to effect
the change of control of, or influence over, the surviving corporation or
organization, as the case may be, or (b) the Company is liquidated or dissolved
or adopts a plan of liquidation or dissolution.

     (h)  Each Nonemployee Director Option shall be nontransferable by the
optionee other than by will or the laws of descent and distribution, and shall
be exercisable during the optionee's lifetime only by the optionee or the
optionee's guardian or legal representative.

     (i)  Nonemployee Director Options are not intended to qualify as Incentive
Stock Options.

     (j)  Any options granted to Nonemployee Directors in addition to the
automatic options granted under Section 10(a) shall be considered "Nonemployee
Director Options" for purposes of this Section 10.



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