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                                                                   Exhibit 10.15

                           MICROSTRATEGY INCORPORATED

                   1999 AMENDED AND RESTATED STOCK OPTION PLAN

                             STOCK OPTION AGREEMENT

        Unless otherwise defined herein, the terms defined in the MicroStrategy
Incorporated 1999 Amended and Restated Stock Option Plan (the "Plan") shall have
the same defined meanings in this Option Agreement.

1.      Grant of Option.

        Participant:    Eduardo Sanchez
        Address:        P.O. Box 9192
                        McLean, VA 22102
                        USA

        You have been granted an option to purchase shares of Class A Common
Stock of MicroStrategy Incorporated, subject to the terms and conditions of the
Plan and this Option Agreement, as follows:

Grant Number:                          15387

Date of Grant:                         July 26, 2002

Vesting Commencement Date:             July 26, 2002

Fair Market Value, Date of Grant:      $ .47

Exercise Price per Share:              $ .47

Total Number of Options Granted:       262,200

Total Exercise Price:                  $123,234.00

Type of Option:                        Nonstatutory Stock Option

Final Exercise Date:                   July 26, 2012

        Except as otherwise indicated by the context, the term "you", as used in
this option, shall be deemed to include any person who acquires the right to
exercise this option validly under its terms.

2.      Vesting Schedule; Definitions.

        (a)     Vesting Schedule. As used herein, the term "vested" shall mean
that portion of this option that is exercisable. This option shall vest in
accordance with the following schedule: (i) except as set forth in (v) and (vi)
below, no portion of this option shall be vested prior to the first anniversary
of your Vesting Commencement Date; (ii) 87,440 options shall be vested on the
first anniversary of your Vesting Commencement Date; (iii) 87,500 options shall
be vested on the second anniversary of your

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Vesting Commencement Date; (iv) 87,260 options shall be vested on the third
anniversary of your Vesting Commencement Date (such that this option shall be
vested in full on the third anniversary of your Vesting Commencement Date); (v)
immediately following the effective time (the "Change in Control Effective
Date") of a Change in Control (as defined below), a portion of this option which
is unvested on the Change in Control Effective Date shall immediately vest so
that at least 50% of the original grant is fully vested and exercisable as of
the Change in Control Effective Date and the remaining unvested portion of the
option shall vest at the rate of 50% of such remaining unvested amount on the
last day of each of the third month and the sixth month after the Change in
Control Effective Date (such that this option shall be vested in full the last
day of the month which is six months after the Change in Control Effective
Date); and (vi) if, following the Change in Control Effective Date, your
employment is terminated by the Company other than for Cause (as defined below)
or by you for Good Reason (as defined below), this option shall vest in full on
the effective date of such termination. The right of exercise shall be
cumulative so that if you do not exercise this option to the maximum extent
permissible in any period, it shall continue to be exercisable, in whole or in
part, with respect to all vested shares until the earlier of the Final Exercise
Date or the termination of this option under Section 3 below or under the Plan.
Additionally, the Board of Directors, or a committee thereof, in it sole
discretion agrees that immediately prior to a Change of Control it shall
consider whether your vesting schedule set forth above should be further
modified so that this option shall become fully vested upon the Change of
Control.

        (b)     Definitions.

                (i)     "Good Reason" shall mean the occurrence, without your
written consent, of any of the following events or circumstances: (A) a
reduction in your annual base salary or bonus opportunity as in effect on the
Change in Control Effective Date, which in no event shall be less than your base
salary and bonus opportunity in effect as of July 24, 2002,or as the same was or
may be increased thereafter from time to time; (B) a change by the Company in
the location at which you perform your principal duties for the Company to a new
location that is both (x) outside a radius of 35 miles from your principal
residence immediately prior to the Change in Control Effective Date and (y) more
than 20 miles from the location at which you performed your principal duties for
the Company immediately prior to the Change in Control Effective Date; or (C) a
requirement by the Company that you travel on Company business for more than 10
business days per month for three consecutive months, or (D) a failure by the
Company to provide you with an executive title, such as vice-president, general
manager, senior director of a corporate function or chief officer of a corporate
function. Notwithstanding the occurrence of any such event or circumstance, such
occurrence shall not be deemed to constitute Good Reason if, prior to the
effective date of such, such event or circumstance has been fully corrected and
you have been reasonably compensated for any losses or damages resulting
therefrom.

                (ii)    "Change in Control" shall mean an event or occurrence
set forth in any one or more of subsections (A) and (B) below (including an
event or occurrence that constitutes a Change in Control under one of such
subsections but is specifically exempted from another such subsection):

                        (A)     the acquisition by an individual, entity or
group (within the meaning of Section 13(d)(3) or 14(d)(2) of the Securities
Exchange Act of 1934, as amended (the "Exchange Act")) (a "Person") of
beneficial ownership of any capital stock of the Company if, after such
acquisition, such Person beneficially owns (within the meaning of Rule 13d-3
promulgated under the Exchange Act) 50% or more of the combined voting power of
the then-outstanding securities of the Company entitled to vote generally in the
election of directors (the "Outstanding Company Voting Securities"); provided,
however, that for purposes of this subsection (A), the following acquisitions
shall not constitute a Change in Control: (i) any acquisition directly from the
Company (excluding an acquisition pursuant to the exercise, conversion or
exchange of any security exercisable for, convertible into or exchangeable for
Class A Common Stock or the Company's Class B Common Stock, $0.001 par value per
share, or voting

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securities of the Company, unless the Person exercising, converting or
exchanging such security acquired such security directly from the Company or an
underwriter or agent of the Company), (ii) any acquisition by the Company, (iii)
any acquisition by any employee benefit plan (or related trust) sponsored or
maintained by the Company or any corporation controlled by the Company, (iv) any
acquisition by any corporation pursuant to a transaction which results in a
Continuity of Interest as defined in subsection (B) of this Section 2(b)(iii),
or (v) any acquisition by Michael J. Saylor or any of his affiliates (each such
party is referred to herein as an "Exempt Person"); or

                        (B)     the consummation of a merger, consolidation,
reorganization, recapitalization or statutory share exchange involving the
Company or a sale or other disposition of all or substantially all of the assets
of the Company in one or a series of transactions (a "Business Combination"),
unless, immediately following such Business Combination, all or substantially
all of the individuals and entities who were the beneficial owners of the
then-outstanding Outstanding Company Voting Securities immediately prior to such
Business Combination beneficially own more than 50% of the then-outstanding
combined voting power of the then-outstanding securities entitled to vote
generally in the election of directors, respectively, of the resulting or
acquiring corporation in such Business Combination (a "Continuity of Interest").

3.      Exercise of Option.

        (a)     Form of Exercise. To exercise this option, you must sign an
Exercise Notice in the form attached hereto as Exhibit A and deliver the
Exercise Notice to the Company at its principal office, accompanied by a copy of
this Option Agreement and payment in full for the shares in the manner provided
in the Plan. You may purchase less than the number of shares covered under this
Option Agreement, but may not partially exercise this option for any fractional
share or for fewer than ten whole shares. This option shall be deemed to be
exercised when the Company receives your fully-executed Exercise Notice, a copy
of this Stock Option Agreement, and payment in full for the shares in the manner
provided in the Plan.

        (b)     Continuous Relationship with the Company Required. Except as
otherwise provided in this Section 3, this option may not be exercised unless
you, at the time you exercise this option, have been at all times since the Date
of Grant, an employee of, or consultant or advisor to, the Company as defined in
Section 424(e) or (f) of the Code (an "Eligible Participant"). You shall not
cease to be an Eligible Participant if you take a leave of absence permitted
under Company policy, including but not limited to sick leave, vacation leave,
leave under the Family Medical Leave Act, jury duty, military leave, or any
other personal leave, or transfers between locations of the Company, or any
other leave that is approved by the Board of Directors of the Company. For each
day that you take a personal leave of absence or leave under the Family Medical
Leave Act (but not sick leave, vacation leave, jury duty, transfers between
locations of the Company or any other leave that is approved by the Board of
Directors) the vesting schedule described in Section 2 above shall be extended
for one additional day. If you take any leave of absence that exceeds ninety
(90) days and this option is designated in Section 1 as an Incentive Stock
Option, then this option shall be deemed a Nonstatutory Stock Option, unless
your reemployment is guaranteed at the end of such leave by contract (including
certain Company policies), statute, or applicable regulation.

        (c)     Termination of Relationship with the Company. If you cease to be
an Eligible Participant for any reason, then except as provided in paragraphs
(d), (e), and (f) below, your right to exercise this option shall terminate
three (3) months from the date of such cessation, but in no event after the
Final Exercise Date; provided that you may only exercise this option to the
extent that you were entitled to do so on the date of such cessation.

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        (d)     Exercise Period upon Death or Disability. If you die or become
disabled (within the meaning of Section 22(e)(3) of the Code) prior to the Final
Exercise Date while you are an Eligible Participant and the Company has not
terminated your relationship for "cause" as defined in paragraph (f) below, then
you or your estate (as applicable) shall be entitled to exercise this option
within twelve (12) months following the date of your death or disability. At the
end of this twelve-month period, this option shall terminate. Notwithstanding
the above, you or your estate may only exercise this option to the extent that
you were entitled to do so on the date of your death or disability, and in no
event shall this option be exercisable after the Final Exercise Date.

        (e)     Compliance with Employment Agreements Required. If you violate
the terms of any employment agreement, non-competition agreement,
non-solicitation agreement, confidentiality agreement, non-disclosure agreement,
intellectual property agreement, or any other agreement or contract between you
and the Company, your right to exercise this option shall terminate immediately
upon such violation.

        (f)     Discharge for Cause. If you are discharged by the Company for
"Cause" as defined below prior to the Final Exercise Date, your right to
exercise this option shall terminate immediately on the effective date of such
discharge. "Cause" shall mean willful misconduct by you or your willful failure
to perform responsibilities to the Company, including your breach of any
employment, consulting, advisory, non-disclosure, non-competition, or similar
agreement between you and the Company, but excluding acts that merely constitute
negligence or gross negligence. You shall be considered to have been discharged
for "cause" if the Company determines, within thirty (30) days after your
resignation, that discharge for cause was warranted and your conduct satisfies
the definition of "Cause" in the preceding sentence.

4.      Withholding.

        No shares will be issued to you upon exercise of this option unless and
until you pay to the Company, or make provision satisfactory to the Company for
payment of, any federal, state, or local withholding taxes required by law to be
withheld with respect to this option.

5.      Nontransferability of Option.

        You shall not sell, assign, transfer, pledge or otherwise encumber this
option, either voluntarily or by operation of law, except by will or the laws of
descent and distribution, and during your lifetime, this option shall be
exercisable only by you.

6.      Disqualifying Distribution.

        If this option is an Incentive Stock Option and you dispose of shares
acquired upon exercise of this option within two years from the Date of Grant or
one year after you acquired such shares, you shall immediately notify the
Company in writing of such disposition.

7.      No Right to Employment.

        If you are an employee, neither the Plan nor this Option Agreement shall
alter in any way your status as an "at-will" employee. You retain your right to
terminate your relationship with the Company at any time, with or without
reason, and the Company retains its right to terminate your relationship at any
time, with or without reason.

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8.      Provisions of the Plan.

        This option is subject to the provisions of the Plan. In the event of a
conflict between the provisions of the Plan and this Option Agreement, the Plan
shall govern.

9.      Entire Agreement; Governing Law.

        The Plan, this Option Agreement, and the attached Exercise Notice
constitute the entire agreement of the parties and supersede in their entirety
all prior undertakings and agreements of the Company and you with respect to the
subject matter hereof. The entire agreement shall be governed by Virginia law
except for that body of law pertaining to conflict of laws.

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        IN WITNESS HEREOF, the Company has caused this option to be executed by
its duly authorized officer. This option shall take effect as a sealed
instrument.

                                    MICROSTRATEGY INCORPORATED

                                    By:      /s/ Michael J. Saylor
                                        ----------------------------------------
                                             Michael J. Saylor
                                    Title:   Chairman & CEO

                            PARTICIPANT'S ACCEPTANCE

        The undersigned hereby accepts the foregoing Option Agreement and agrees
to the terms and conditions thereof. The undersigned hereby acknowledges
receiving a copy of the Plan. The undersigned has reviewed the Plan and this
Option Agreement in their entirety, has had an opportunity to obtain the advice
of counsel before executing this Option Agreement and fully understands all
provisions of the Plan and this Option Agreement. The undersigned hereby agrees
to accept as binding, conclusive and final all decisions or interpretations of
the Company upon any questions relating to the Plan and Option Agreement.

                                    PARTICIPANT:

                                             /s/ Eduardo S. Sanchez
                                    --------------------------------------------
                                    Signature
                                             Eduardo S. Sanchez
                                    --------------------------------------------
                                    Print Name

                                CONSENT OF SPOUSE

        The undersigned spouse of the Participant has read and hereby approves
the terms and conditions of the Plan and this Option Agreement. In consideration
of the Company's granting his or her spouse the right to purchase shares as set
forth in the Plan and this Option Agreement, the undersigned hereby agrees to be
irrevocably bound by the terms and conditions of the Plan and this Option
Agreement and further agrees that any community property interest shall be
similarly bound. The undersigned hereby appoints the undersigned's spouse as
attorney-in-fact for the undersigned with respect to any amendment or exercise
of rights under the Plan or this Option Agreement.

                                    SPOUSE OF PARTICIPANT:

                                             /s/ Mary Cook
                                    --------------------------------------------
                                    Signature
                                             Mary Cook
                                    --------------------------------------------
                                    Print Name

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                     EXHIBIT A TO THE STOCK OPTION AGREEMENT

                           MICROSTRATEGY INCORPORATED

                   1999 AMENDED AND RESTATED STOCK OPTION PLAN

                                 EXERCISE NOTICE

MicroStrategy Incorporated
1861 International Drive
McLean, VA 22102
Attention:  Stock Option Administrator

        1.      Exercise of Option. Effective as of today, ________________,
200__, I, _________________________________ ("Purchaser"), hereby elect to
purchase ___________ shares (the "Shares") of the Class A Common Stock of
MicroStrategy Incorporated (the "Company") under and pursuant to the
MicroStrategy Incorporated 1999 Amended and Restated Stock Option Plan (the
"Plan") and the Stock Option Agreement listed below (the "Option Agreement"):

<TABLE>
<CAPTION>
                                            Number of Shares    Exercise              Aggregate
Grant Number          Date of Grant         Being Exercised     Price Per Share       Exercise Price
------------------------------------------------------------------------------------------------------------
<S>                   <C>                   <C>                 <C>                   <C>
                                                                $                     $
------------------------------------------------------------------------------------------------------------
</TABLE>

        2.      Delivery of Payment. Purchaser herewith delivers to the Company
the full purchase price for the Shares.

        3.      Representations of Purchaser. Purchaser acknowledges that
Purchaser has received, read and understood the Plan and the Option Agreement
and agrees to abide by and be bound by their terms and conditions.

        4.      Rights as Stockholder. Subject to the terms and conditions of
the Plan, the Option Agreement, and this Exercise Notice, Purchaser shall have
all of the rights of a stockholder of the Company with respect to the Shares
from and after the date the stock certificate evidencing such Shares is issued,
as evidenced by the appropriate entry on the books of the Company or of a duly
authorized transfer agent of the Company.

        5.      Tax Consultation. Purchaser understands that Purchaser may
suffer adverse tax consequences as a result of Purchaser's purchase or
disposition of the Shares. Purchaser represents that Purchaser has consulted
with any tax consultants Purchaser deems advisable in connection with the
purchase or disposition of the Shares and that Purchaser is not relying on the
Company for any tax advice.

        6.      Interpretation. Any dispute regarding the interpretation of the
Plan, the Option Agreement, or this Exercise Notice shall be submitted by
Purchaser or by the Company forthwith to the Company's Board of Directors or the
committee thereof that administers the Plan, which shall review such dispute at
its next regular meeting. The resolution of such a dispute by the Board or
committee shall be final and binding on the Company and on Purchaser.

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        7.      Entire Agreement; Governing Law. The Plan, the Option Agreement,
and this Exercise Notice constitute the entire agreement of the parties and
supersede in their entirety all prior undertakings and agreements of the Company
and Purchaser with respect to the subject matter hereof. The entire agreement
shall be governed by Virginia law except for that body of law pertaining to
conflict of laws.

Submitted by:                       Accepted by:

PURCHASER:                          MicroStrategy Incorporated

-----------------------------       By:
Signature                               ----------------------------------
                                                 Michael J. Saylor

-----------------------------       Title:   Chairman & CEO
Print Name

-----------------------------       Address:
Tax I.D. Number
                                    1861 International Drive

-----------------------------       McLean, VA  22102
Address

-----------------------------
City, State, Zip      Country

Brokerage Account Information (voluntary)*

-----------------------------            * This section will also need to be
Broker Name                              completed if you would like your shares
                                         to be wired directly to your brokerage
                                         account, which generally takes a few
-----------------------------            business days. If you do not supply
Broker DTC Number                        brokerage account information, your
                                         stock certificate will be mailed to
                                         you. Please note that it can take
-----------------------------            several weeks before you receive shares
Account Number                           by mail.

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