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                                                                    Exhibit 10.3


                         FIRST MODIFICATION AGREEMENT


       THIS FIRST MODIFICATION AGREEMENT (this "Agreement"), dated as of the
15th day of May 2000, is by and among BANK OF AMERICA, N.A., a national banking
association and successor to NationsBank, N.A. (the "Bank"); MICROSTRATEGY
INCORPORATED, a Delaware corporation (the "Borrower"); and MICHAEL J. SAYLOR and
ALCANTARA LLC, a Delaware limited liability company (the "Guarantors").


                               WITNESSETH THAT:

       WHEREAS, the Bank is the owner and holder of that certain Revolving
Commercial Note dated March 26, 1999, made by the Borrower and payable to the
order of the Bank, in the original principal amount of Twenty-five Million and
no/100 Dollars ($25,000,000.00) and bearing interest and being payable in
accordance with the terms and conditions therein set forth (the "Note"); and

       WHEREAS, the Note was issued pursuant to a certain Credit Agreement dated
March 26, 1999, between the Borrower and the Bank (the "Credit Agreement"); and

       WHEREAS, as of the date hereof, the principal balance of the Note is Zero
Dollars ($0.00), the outstanding amount of issued Letters of Credit (as defined
in the Credit Agreement) is $3,859,464.01 and the parties hereto desire to
modify the terms of the Note and the Credit Agreement.

       NOW, THEREFORE, for Ten Dollars ($10.00) and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

       1.   The Credit Agreement is hereby modified, effective March 30, 2000,
as follows:

            (a) In Section 1.1,

                (i) by replacing "NationsBank, N.A." with "Bank of America,
N.A., a national banking association and successor to NationsBank, N.A." in the
definition of "Bank".

                (ii) by inserting ", contingent or otherwise," after
"obligations" in clause (c) of the definition of "Debt"; and

                (iii)  by adding the following new definitions:

       "Guarantor" means Michael J. Saylor and his successors, or Alcantara LLC,
     a Delaware limited liability company and its successors; and "Guarantors"
     means both of said Persons.
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       "Royal Caribbean Letter of Credit" means the Letter of Credit in the
     amount of US$3,600,000.00, to be requested by the Borrower and issued by
     the Bank for the benefit of Royal Caribbean Cruises LTD, together with all
     renewals, modifications and increases thereof, and replacements thereto.


            (b) In Section 2.1,

                (i) by inserting "(subject to subsection (c) of this Section
2.1)" after "$25,000,000.00" in subsection (a) and after "$5,000,000.00" in
subsection (b); and

                (ii) by adding a new subsection (c), as follows:

       (c) The Royal Caribbean Letter of Credit. Upon the issuance by the Bank
           ------------------------------------
     of the Royal Caribbean Letter of Credit, the Commitment shall be increased
     automatically to $28,600,000.00 and the Letter of Credit Commitment shall
     be increased automatically to the lesser of $8,600,000.00 (or the
     equivalent in foreign currency, as determined by the Bank in its sole
     discretion) and the unused Commitment. As the undrawn amount of the Royal
     Caribbean Letter of Credit decreases (by cancellation, expiration, draws,
     or otherwise), each of the Commitment and the Letter of Credit Commitment
     shall be reduced by the amount of said decrease. Once decreased as
     aforesaid, neither the Commitment nor the Letter of Credit Commitment may
     thereafter be increased.

            (c) In Article IV,

                (i) by inserting "except as set forth on Schedule IV hereto, as
supplemented by information supplied by the Borrower to the Bank," after "Since
December 31, 1998" in Section 4.4(c);

                (ii) by inserting "and except as set forth on Schedule IV
hereto, as supplemented by information supplied by the Borrower to the Bank,"
after "To the knowledge of the Borrower" in Section 4.5; and

                (iii) by inserting "and except as set forth on Schedule IV
hereto, as supplemented by information supplied by the Borrower to the Bank,"
after "To the best of the Borrower's knowledge" in the last sentence of Section
4.13.


            (d) Article V thereof is deleted in its entirety and replaced with
the following:

                                   ARTICLE V
                            [intentionally deleted]

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            (e) In Section 7.1,

                (i) by deleting "in Article V or" from clause (ii);

                (ii) by deleting clause (iv) in its entirety and replacing it
with the following:

       (iv) any representation, warranty, certification or statement made by or
     on behalf of the Borrower or either of the Guarantors in this Agreement,
     any Application, or in any other instrument or agreement which now or
     hereafter evidences, secures or guarantees any Loan, or by or on behalf of
     the Borrower or either of the Guarantors in any certificate, financial
     statement or other document delivered after May 15, 2000 pursuant hereto or
     thereto shall prove to have been incorrect in any material respect when
     made;

                (iii) by inserting ", either of the Guarantors," between "the
Borrower" and "or any Subsidiary of the Borrower" in clauses (v), (vi), (vii),
(viii) and (x);

                (iv) by replacing "in excess of $500,000 over the limit of
applicable insurance coverage" in clause (x) with "which would cause the total
of all such judgments and orders to exceed $15,000,000.00 in the aggregate"; and

                (v) by adding new clause (xi) as follows:

          (xi) any indorsement or guaranty of the payment of the Note or any
   Loan shall cease for any reason to be in full force and effect, or any
   indorser or guarantor (including, without limitation, either Guarantor) shall
   contest the validity or enforceability of the indorsement or guaranty or deny
   that it has any further liability or obligation under the indorsement or
   guaranty, or the breach of any representation, warranty or agreement
   contained in said indorsement or guaranty; or any agreement or other document
   granting the Bank security for the payment of any Loan or any such
   indorsement or guaranty shall cease for any reason to be in full force and
   effect as such security with the priority stated to be created thereby, or
   the grantor of such security shall contest the validity or enforceability of
   the security or deny that it has any further liability or obligation under
   such agreement or other document, or the breach of any representation,
   warranty, or agreement contained in said agreement or other document;

       2.   The "INTEREST RATE" section of the Note is hereby deleted in its
entirety and replaced with the following:

            INTEREST RATE. This Note shall bear interest on the outstanding
     principal balance from time to time at a variable rate per annum equal at
     all times to 1.75% over the LIBOR Rate.  The "LIBOR Rate" means that
     variable rate of

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     interest (rounded upwards, if necessary, to the nearest 1/100 of 1%)
     appearing on Telerate Page 3750 (or any successor page) as the one-month
     London interbank offered rate for deposits in U.S. Dollars at approximately
     11:00 a.m. (London time) on the second preceding business day, as adjusted
     from time to time in the Bank's sole discretion for then-applicable reserve
     requirements, deposit insurance assessment rates and other regulatory
     costs. If, for any reason, such rate is not available, the term "LIBOR
     Rate" shall mean the fluctuating rate of interest equal to the one-month
     rate of interest (rounded upwards, if necessary, to the nearest 1/100 of
     1%) appearing on Reuters Screen LIBO Page as the one-month London interbank
     offered rate for deposits in Dollars at approximately 11:00 a.m. (London
     time) on the second preceding business day as adjusted from time to time in
     the Bank's sole discretion for then-applicable reserve requirements,
     deposit insurance assessment rates and other regulatory costs; provided,
     however, if more than one rate is specified on Reuters Screen LIBO Page,
     the applicable rate shall be the arithmetic mean of all such rates. Changes
     in the interest rate on this Note shall take place, without notice, in
     accordance with changes in the LIBOR Rate, as and when such changes occur.

       Interest shall be computed on the basis of a 360 day year, counting the
     actual number of days elapsed.

       Upon the maturity of this Note (whether scheduled, by acceleration, or
     otherwise), this Note shall bear interest, payable on demand, for each day
     until paid at a rate per annum equal to the sum of 4.0% plus the otherwise
     applicable interest rate.

       3.   The Bank's modification fee of $50,000.00, plus the reasonable fees
and expenses of the Bank's legal counsel in connection with this modification
and related transactions, shall be paid by the Borrower on the date hereof.

       4.   Contemporaneously with the execution and delivery of this Agreement,
the Borrower shall execute and deliver, or cause to be executed and delivered,
to the Bank (i) the guaranties of Michael J. Saylor and Alcantara LLC; (ii) the
pledge and security agreement of Alcantara LLC providing collateral security for
such guaranty of Alcantara LLC and for the obligations of the Borrower under the
Credit Agreement and the Note and Applications (as defined in the Credit
Agreement); (iii) the opinion of Hale and Dorr LLP, as to such matters as the
Bank shall require, including, without limitation, the validity of the agreement
referenced in clause (ii) hereof, the validity of the security interest created
thereby, and the perfection of said security interest; and (iv) all documents,
schedules, exhibits and agreements required by any of the foregoing to be
delivered in connection therewith (all of the foregoing being referred to herein
as the "Closing Documents").   All Closing Documents shall be on the Bank's
forms therefor and appropriately completed, or otherwise satisfactory to the
Bank and its counsel.  Upon the delivery of the Closing Documents as set forth
above, the "Events of Default" described in that certain letter from the Bank to
the Borrower dated May 10, 2000, shall be deemed to have been cured; and, upon
the delivery to the Bank of the opinion

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of Hunton & Williams, special counsel to the Borrower and Alcantara LLC, that
the aforesaid security interest is of the first priority, the Commitment and the
Letter of Credit Commitment, as defined in, and subject to, the Credit Agreement
as modified hereby, shall be reinstated.

       5.   The Borrower and the Guarantor hereby acknowledge and agree that, as
of the date hereof, the unpaid principal balance of the Note is Zero Dollars
($0.00), the outstanding amount of issued Letters of Credit is $3,859,464.01 and
that there are no set-offs or defenses against the Note, the Credit Agreement,
or any Application (as defined in the Credit Agreement).

       6.   The Guarantors join in this Agreement for the purpose of signifying
their consent hereto and agree to execute and deliver the documents described in
Paragraph 4 hereof to be executed and delivered by them.

       7.   The parties to this Agreement do not intend that this Agreement be
construed as a novation of the Note, the Credit Agreement or any Application.

       8.   Except as hereby expressly modified, the Credit Agreement and the
Note shall otherwise be unchanged, shall remain in full force and effect, and
are hereby expressly approved, ratified and confirmed.  A legend shall be placed
on the Note indicating that its terms have been modified hereby, and the
original of this Agreement shall be affixed to the original of the Note.

       9.   This Agreement shall be governed in all respects by the laws of the
Commonwealth of Virginia and shall be binding upon and shall inure to the
benefit of the parties hereto and their respective heirs, executors,
administrators, personal representatives, successors and assigns.

WITNESS the following signatures and seals.

                              MICROSTRATEGY INCORPORATED     [SEAL]



                              By___________________________________
                                    Name:
                                    Title:



                              ______________________________  [SEAL]
                              MICHAEL J. SAYLOR

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                              ALCANTARA LLC             [SEAL]



                              By: /s/ Michael J. Saylor
                                  ---------------------------------
                                    Michael J. Saylor, President
                                    and Sole Member


                              BANK OF AMERICA, N.A.  [SEAL]



                              By: /s/
                                  ---------------------------------
                                    Name:
                                    Title:

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