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                                                                    EXHIBIT 10.2

                                  Marimba, Inc.

                     1999 Non-Employee Directors Option Plan

                       Amended and Restated July 20, 2001

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                                  MARIMBA, INC.
                     1999 NON-EMPLOYEE DIRECTORS OPTION PLAN

   ARTICLE 1. PURPOSE OF THE PLAN

     The Plan is intended to promote the interests of the Company by providing
the non-employee members of the Board with the opportunity to acquire a
proprietary interest, or otherwise increase their proprietary interest, in the
Company as an incentive for them to remain in the service of the Company.

   ARTICLE 2. ADMINISTRATION

     The terms and conditions of each automatic option grant (including the
timing and pricing of the option grant) shall be determined by the express terms
and conditions of the Plan, and neither the Board nor any committee of the Board
shall exercise any discretionary functions with respect to option grants made
pursuant to the Plan.

   ARTICLE 3. STOCK SUBJECT TO THE PLAN

     A. Shares of Common Stock shall be available for issuance under the Plan
and shall be drawn from either the Company's authorized but unissued shares of
Common Stock or from reacquired shares of Common Stock, including shares
repurchased by the Company on the open market. The number of shares of Common
Stock reserved for issuance over the term of the Plan shall be fixed at 150,000
shares. As of January 1 of each year, starting in 2000, the aggregate number of
shares of Common Stock available for purchase during the life of the Plan shall
automatically be increased by the number of shares necessary to cause the number
of shares then available for purchase to be restored to 150,000.

     B. Should one or more outstanding options under this Plan expire or
terminate for any reason prior to exercise in full, then the shares subject to
the portion of each option not so exercised shall be available for subsequent
option grant under the Plan. In addition, should the exercise price of an
outstanding option under the Plan be paid with shares of Common Stock, then the
number of shares of Common Stock available for issuance under the Plan shall be
reduced by the net number of shares of Common Stock actually issued to the
holder of such option.

     C. Should any change be made to the Common Stock issuable under the Plan by
reason of any stock split, stock dividend, recapitalization, combination of
shares, exchange of shares or other change affecting the outstanding Common
Stock as a class without the Company's receipt of consideration, then
appropriate adjustments shall be made to (i) the maximum number and/or class of
securities issuable under the Plan, (ii) the number and/or class of securities
for which automatic option grants are to be subsequently made to each
newly-elected or continuing non-employee Board member under the Plan, and (iii)
the number and/or class of securities and price per share in effect under each
option outstanding under the Plan. The adjustments to the outstanding options
shall be made by the Board in a manner which shall

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preclude the enlargement or dilution of rights and benefits under such options
and shall be final, binding and conclusive.

   ARTICLE 4.  ELIGIBILITY

     The individuals eligible to receive automatic option grants pursuant to the
provisions of this Plan shall be limited to (i) those individuals serving as
non-employee Board members on the effective date of the IPO and (ii) those
individuals who are first elected or appointed as non-employee Board members
after the effective date of the IPO, whether through appointment by the Board or
election by the Company's stockholders. A non-employee Board member shall not be
eligible to receive the initial automatic option grant described in Section
5.A.2 if such individual has previously been in the employ of the Company (or
any parent or subsidiary). However, a non-employee Board member shall be
eligible to receive one or more annual option grants described in Section 5.A.3
or 5.A.4, whether or not he or she has previously been in the employ of the
Company (or any parent or subsidiary). Each non-employee Board member eligible
to participate in the Plan pursuant to the foregoing criteria is hereby
designated an Eligible Director.

   ARTICLE 5.  TERMS AND CONDITIONS OF AUTOMATIC OPTION GRANTS

     A. Grant Date. Option grants shall be made on the dates specified
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below:

                  1. Each individual who first became an Eligible Director prior
to 1999 and is an Eligible Director on the effective date of the IPO shall
automatically be granted, on the effective date of the IPO, a fully vested
non-statutory option to purchase 7,500 shares of Common Stock.

                  2. Each individual who first becomes an Eligible date of the
IPO but before September 6, 2001, whether through election by the Director after
the effective Company's stockholders or appointment by the Board, shall
automatically be granted, at the time of such initial election or appointment, a
fully vested non-statutory option to purchase 15,000 shares of Common Stock.
Each individual who first becomes an Eligible Director on or after September 6,
2001, whether through election by the Company's stockholders or appointment by
the Board, shall automatically be granted, at the time of such initial election
or appointment, a non-statutory option to purchase 30,000 shares of Common
Stock. The 30,000-share option shall vest in two equal annual installments
measured from the date of grant, provided the individual remains an Eligible
Director until the option vests.

                  3. On the date of each Annual Meeting, beginning with
the 2001 Annual Meeting, each Eligible Director who serves on the Board at the
time of that Annual Meeting, whether or not standing for re-election, shall
automatically be granted a non-statutory option to purchase 10,000 shares of
Common Stock. An Eligible Director who resigns effective at an Annual Meeting
shall not be eligible to be granted a non-statutory option at that time. The
option shall vest in full after one year, measured from the date of grant,
provided the individual remains an Eligible Director until the option vests.
There shall be no limit on the number of such annual 10,000-share option

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grants any one Eligible Director may receive over his or her period of continued
Board service. Notwithstanding anything in this Section 5.A.3 to the contrary,
an individual who first becomes an Eligible Director between July 19, 2001 and
September 5, 2001 and who serves on the Board on the date of the 2001 Annual
Meeting, shall automatically be granted a non-statutory option to purchase
15,000 shares of Common Stock. The 15,000- share option grant shall vest in two
equal annual installments measured from the date of grant, provided the
individual remains an Eligible Director until the option vests.

                  4. On the date of each Annual Meeting, beginning with the 2001
Annual Meeting, each Eligible Director who serves on a committee of the Board at
that time, shall automatically be granted a non-statutory option to purchase
2,500 shares of Common Stock for each committee on which he or she serves. The
option shall vest in full after one year measured from the date of grant,
provided the individual remains an Eligible Director and continues to serve on
such committee or committees until the option vests. There shall be no limit on
the number of such annual 2,500-share option grants any one Eligible Director
may receive over his or her period of continued Board service.

                  5. However, each Eligible Director who in a calendar year
received an initial non-statutory option under this Plan (as described in
Section 5.A.2) shall first be eligible to be granted a non-statutory option to
purchase 10,000 shares of Common Stock under this Plan (as described in Section
5.A.3) at the Annual Meeting occurring at any time in the year that is two
calendar years following the year in which the Eligible Director received the
non-statutory option to purchase 15,000 or 30,000 shares under this Plan (as
described in Section 5.A.2). For example, if an Eligible Director received a
non-statutory option to purchase 30,000 shares of Common Stock (as described in
Section 5.A.2) in 2001, this Eligible Director will first become eligible to
receive a non-statutory option to purchase 10,000 shares of Common Stock (as
described in Section 5.A.3) at the Annual Meeting occurring in 2003. The
restrictions set forth in this Section 5.A.5 shall not apply to the 15,000-share
option grant described in Section 5.A.3, above.

          B. Exercise Price. The exercise price per share of Common Stock
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subject to each automatic option grant shall be equal to one hundred percent
(100%) of the Fair Market Value per share of Common Stock on the automatic grant
date, except that the exercise price per share of Common Stock subject to the
automatic grant described in Section 5.A.1 above will be the initial price
offered to the public on the effective date of the IPO.

          C. Payment.
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          The exercise price shall become immediately due upon exercise of the
option and shall be payable in one of the alternative forms specified below:

             (i) all or part of the exercise price may be paid in cash or check
made payable to the Company's order; or

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             (ii)    all or part of the exercise price may be paid by
surrendering, or attesting to the ownership of, shares of Common Stock that are
already owned by the Optionee. Such shares of Common Stock shall be valued at
their Fair Market Value on the date when the new shares of Common Stock are
purchased under the Plan. The Optionee shall not surrender, or attest to the
ownership of, shares of Common Stock in payment of the exercise price if such
action would cause the Company to recognize compensation expense (or additional
compensation expense) with respect to the option for financial reporting
purposes; or

              (iii)  all or part of the exercise price may be paid by delivering
(on a form prescribed by the Company) an irrevocable direction to a securities
broker approved by the Company to sell all or part of the shares of Common Stock
being purchased under the Plan and to deliver all or part of the sales proceeds
to the Company; or

              (iv)   all or part of the exercise price may be paid by delivering
(on a form prescribed by the Company) an irrevocable direction to pledge all or
part of the shares of Common Stock being purchased under the Plan to a
securities broker or lender approved by the Company, as security for a loan, and
to deliver all or part of the loan proceeds to the Company.

          D.  Exercisability/Vesting. Each automatic option grant shall vest as
              ----------------------
described in Section 5.A above and shall be subject to acceleration as provided
in Article 6.

          E.  Option Term. Each automatic option grant under the Plan shall have
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a maximum term of ten (10) years measured from the automatic grant date.

          F.  Non-Transferability. During the lifetime of the Optionee, each
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automatic option grant shall be exercisable only by the Optionee and shall not
be assignable or transferable by the Optionee other than a transfer of the
option effected by will or by the laws of descent and distribution following
Optionee's death.

          G.  Effect of Termination of Board Service.
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                1.   Should the Optionee cease to serve as a Board member for
any reason (including Disability or death) while holding one or more automatic
option grants under the Plan, then such individual shall have a twelve-month
period following the date of such cessation of Board service in which to
exercise each such option for any or all of the option shares for which the
option is vested and exercisable at the time of his or her cessation of Board
service.

               2. Should the Optionee die while serving as a Board member, then
any automatic option grant held by the Optionee at the time of death may
subsequently be exercised, for the option shares for which the option is vested
and exercisable at the time of his or her cessation of Board service (less any
option shares purchased by the Optionee prior to death), by the personal
representative of the Optionee's estate or by the person or persons to whom the
option is transferred pursuant to the Optionee's will or in accordance with the
laws of descent and distribution. The right to exercise each such option shall
lapse upon the expiration of the twelve-month period measured from the date of
the Optionee's cessation of service.

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               3.    In no event shall any automatic option grant under this
Plan remain exercisable after the expiration date of the maximum ten-year option
term. Upon the expiration of the applicable post-service exercise period under
subparagraphs 1 through 2 above or (if earlier) upon the expiration of the
maximum ten-year option term, the unexercised automatic option grant shall
terminate and cease to be outstanding.

          H.  Stockholder Rights. The holder of an automatic option grant shall
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have none of the rights of a stockholder with respect to any shares subject to
such option until such individual shall have exercised the option and paid the
exercise price for the purchased shares.

          I.  Remaining Terms. The remaining terms and conditions of each
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automatic option grant shall be as set forth in the form Stock Option Agreement
approved for use under the Plan.

          J. Affiliates of Eligible Directors. The Board may provide that the
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non-statutory options that otherwise would be granted to an Eligible Director
under this Article 5 shall instead be granted to an affiliate of such Eligible
Director. Such affiliate shall then be deemed to be an Eligible Director for
purposes of the Plan, provided that the service-related termination provisions
pertaining to the non-statutory options shall be applied with regard to the
service of the Eligible Director.

     ARTICLE 6. CHANGE IN CONTROL

          A.  Unless the applicable agreement evidencing the option provides
otherwise, in the event of any Change in Control, the vesting of each
outstanding option shall automatically accelerate so that each such option
shall, immediately prior to the closing date of the Change in Control, become
fully exercisable for all of the shares of Common Stock at the time subject to
such option and may be exercised for any or all of those shares as fully-vested
shares of Common Stock. However, an outstanding option shall not so accelerate
if and to the extent such option, in connection with the Change in Control,
remains outstanding, or is assumed by the surviving corporation (or parent
thereof) or substituted with an option with substantially the same terms by the
surviving corporation (or parent thereof). The determination of whether a
substituted option has substantially the same terms as an option granted by the
Company shall be made by the Committee, and its determination shall be final,
binding and conclusive.

          B.  In the event that an Eligible Director does not become a member of
the board of directors of a surviving corporation (or parent thereof) upon the
closing date of a Change in Control, the vesting of 50% of the unvested shares
of Common Stock at the time subject to each outstanding option of such Eligible
Director shall automatically accelerate so that each such option shall,
immediately prior to the specified closing date for the Change in Control,
become exercisable for 50% of the unvested shares of Common Stock at the time
subject to that option. Immediately following the consummation of the Change in
Control, each automatic option grant under the Plan shall terminate and cease to
be outstanding, except to the extent assumed by the surviving corporation (or
parent thereof).

          C. The automatic option grants outstanding under the Plan shall in no
way affect the right of the Company to adjust, reclassify, reorganize or
otherwise change its capital or

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business structure or to merge, consolidate, dissolve, liquidate or sell or
transfer all or any part of its business or assets.

     ARTICLE 7.  DISSOLUTION, LIQUIDATION AND REORGANIZATIONS

          A.  Dissolution and Liquidations. To the extent not previously
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exercised, options shall terminate immediately prior to the dissolution or
liquidation of the Company.

          B. Reorganizations. In the event that the Company is a party to a
             ---------------
merger or other reorganization, outstanding options shall be subject to the
agreement of merger or reorganization. Such agreement shall provide for (a) the
continuation of the outstanding options by the Company, if the Company is a
surviving corporation, (b) the assumption of the outstanding options by the
surviving corporation or its parent or subsidiary, (c) the substitution by the
surviving corporation or its parent or subsidiary of its own awards for the
outstanding options, (d) full exercisability or vesting and accelerated
expiration of the outstanding options or (e) settlement of the full value of the
outstanding options in cash or cash equivalents followed by cancellation of such
options.

     ARTICLE 8.  AMENDMENT OF THE PLAN AND AWARDS

          The Board has complete and exclusive power and authority to amend or
modify the Plan (or any component thereof) in any or all respects whatsoever.
However, no such amendment or modification shall adversely affect rights and
obligations with respect to options at the time outstanding under the Plan,
unless the affected Optionees consent to such amendment. Stockholder approval
shall be obtained to the extent required by applicable law. The Board amended
the Plan on July 20, 2001, subject to the approval of the Company's stockholders
at the 2001 Annual Stockholders Meeting, to (i) change the number of option
shares granted to Eligible Directors from 15,000 shares to 30,000 shares for an
initial grant under Section 5.A.2, (ii) change the number of option shares
granted at each Annual Meeting from 7,500 to 10,000 for annual option grants
under Section 5.A.3, and provide that any individual who first becomes an
Eligible Director between July 19, 2001 and September 5, 2001 shall receive a
15,000-share option grant at the 2001 Annual Stockholders Meeting, (iii) add a
new Section 5.A.4 providing for an annual option grant of 2,500 shares for
committee membership, and (iv) provide for vesting of the initial grants and
annual grants.

     ARTICLE 9.  EFFECTIVE DATE AND TERM OF PLAN

          A. The Plan shall become effective on the effective date of the IPO.
One or more automatic option grants may be made under the Plan at any time on or
after the effective date of the IPO.

          B. The Plan shall terminate upon the earlier of (i) February 1, 2009
or (ii) the date on which all shares available for issuance under the Plan shall
have been issued pursuant to the exercise of the options granted under the Plan.
If the date of termination is determined under clause (i) above, then all option
grants outstanding on such date shall thereafter continue to have force and
effect in accordance with the provisions of the agreements evidencing those
option grants.

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     ARTICLE 10.  USE OF PROCEEDS

          Any cash proceeds received by the Company from the sale of shares
pursuant to option grants under the Plan shall be used for general corporate
purposes.

     ARTICLE 11.  REGULATORY APPROVALS

          A.  The implementation of the Plan, the granting of any option under
the Plan and the issuance of Common Stock upon the exercise of the option grants
made hereunder shall be subject to the Company's procurement of all approvals
and permits required by regulatory authorities having jurisdiction over the
Plan, the options granted under it, and the Common Stock issued pursuant to it.

          B.  No shares of Common Stock or other assets shall be issued or
delivered under this Plan unless and until there shall have been compliance with
all applicable requirements of Federal and state securities laws, including the
filing and effectiveness of the Form S-8 registration statement for the shares
of Common Stock issuable under the Plan, and all applicable listing requirements
of the Nasdaq National Market or any stock exchange on which the Common Stock is
then listed for trading.

     ARTICLE 12.  NO IMPAIRMENT OF RIGHTS

          Neither the action of the Company in establishing the Plan nor any
provision of the Plan shall be construed or interpreted so as to affect
adversely or otherwise impair the right of the Company or the stockholders to
remove any individual from the Board at any time in accordance with the
provisions of applicable law.

     ARTICLE 13.  MISCELLANEOUS PROVISIONS

          A.  The right to acquire Common Stock or other assets under the Plan
may not be assigned, encumbered or otherwise transferred by any Optionee.

          B.  The provisions of the Plan relating to the exercise of options
shall be governed by the laws of the State of Delaware, as such laws are applied
to contracts entered into and performed in such State, except for their
choice-of-law provisions.

          C.  The provisions of the Plan shall inure to the benefit of, and be

binding upon, the Company and its successors or assigns, whether by a change in
control or otherwise, and the Optionees, the legal representatives of their
respective estates, their respective heirs or legatees and their permitted
assignees.

     ARTICLE 14.  DEFINITIONS

          Annual Meeting: the annual meeting of the Company's stockholders.

          Board: the Company's Board of Directors.

          Code: the Internal Revenue Code of 1986, as amended.

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              Change in Control:

     (a)  The consummation of a merger or consolidation of the Company with or
into another entity or any other corporate reorganization, if more than 50% of
the combined voting power of the continuing or surviving entity's securities
outstanding immediately after such merger, consolidation or other reorganization
is owned by persons who were not stockholders of the Company immediately prior
to such merger, consolidation or other reorganization;

     (b)  The sale, transfer or other disposition of all or substantially all of
the Company's assets;

     (c)  A change in the composition of the Board, as a result of which fewer
than 50% of the incumbent directors are directors who either (i) had been
directors of the Company on the date 24 months prior to the date of the event
that may constitute a Change in Control (the "original directors") or (ii) were
elected, or nominated for election, to the Board with the affirmative votes of
at least a majority of the aggregate of the original directors who were still in
office at the time of the election or nomination and the directors whose
election or nomination was previously so approved; or

     (d)  Any transaction as a result of which any person is the "beneficial
owner" (as defined in Rule 13d-3 under the 1934 Act), directly or indirectly, of
securities of the Company representing at least 50% of the total voting power
represented by the Company's then outstanding voting securities. For purposes of
this Paragraph (d), the term "person" shall have the same meaning as when used
in sections 13(d) and 14(d) of the 1934 Act but shall exclude (i) a trustee or
other fiduciary holding securities under an employee benefit plan of the Company
or of a Parent or Subsidiary and (ii) a corporation owned directly or indirectly
by the stockholders of the Company in substantially the same proportions as
their ownership of the shares of Common Stock of the Company.

          A transaction shall not constitute a Change in Control if its sole
          purpose is to change the state of the Company's incorporation or to
          create a holding company that will be owned in substantially the same
          proportions by the persons who held the Company's securities
          immediately before such transaction.

               B. Committee: A committee of the Board which shall consist
exclusively of two or more directors of the Company, who shall be appointed by
the Board. In addition, the composition of the Committee shall satisfy:

     (a)  Such requirements as the Securities and Exchange Commission may
establish for administrators acting under plans intended to qualify for
exemption under Rule 16b-3 (or its successor) under the 1934 Act; and

     (b)  Such requirements as the Internal Revenue Service may establish for
outside directors acting under plans intended to qualify for exemption under
section 162(m)(4)(C) of the Code.

          Common Stock: shares of the Company's common stock.

          Company: Marimba, Inc., a Delaware corporation.

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               Disability: the inability to engage in any substantial gainful
activity by reason of any medically determinable physical or mental impairment.

               Eligible Director: a member of the Board who is eligible to
receive options under this Plan as described in Article 4 of the Plan.

               Fair Market Value: the market price of shares of Common Stock,
determined by the Board in good faith on such basis as it deems appropriate.
Whenever possible, the determination of Fair Market Value by the Board shall be
based on the prices reported in The Wall Street Journal. Such determination
                                -----------------------
shall be conclusive and binding on all persons.

               IPO: the initial offering of Common Stock to the public pursuant
to a registration statement filed by the Company with the Securities and
Exchange Commission.

               1934 Act: the Securities Exchange Act of 1934, as amended.

               Optionee: any person to whom an option is granted under the Plan.

               Parent: any corporation (other than the Company) in an unbroken
chain of corporations ending with the Company, if each of the corporations other
than the Company owns stock possessing 50% or more of the total combined voting
power of all classes of stock in one of the other corporations in such chain. A
corporation that attains the status of a Parent on a date after the adoption of
the Plan shall be considered a Parent commencing as of such date.

               Plan: this Marimba, Inc. 1999 Non-Employee Directors Option Plan.

               Subsidiary: means any corporation (other than the Company) in an
unbroken chain of corporations beginning with the Company, if each of the
corporations other than the last corporation in the unbroken chain owns stock
possessing 50% or more of the total combined voting power of all classes of
stock in one of the other corporations in such chain. A corporation that attains
the status of a Subsidiary on a date after the adoption of the Plan shall be
considered a Subsidiary commencing as of such date.

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