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                            THIRD AMENDMENT TO LEASE


       THIS THIRD AMENDMENT TO LEASE ("Third Amendment") is made and entered
into this 21 day of June, 1999, by and between GATEWAY VIRGINIA PROPERTIES,
INC., a California corporation ("Landlord") and CYBERCASH, INC., a Delaware
corporation ("Tenant").


                              W I T N E S S E T H:


            WHEREAS, Landlord and Tenant entered into that certain Office Lease
dated November 30, 1994 (the "Original Lease"), as amended by that certain First
Amendment to Lease dated November 7, 1995 (the "First Amendment"), and as
further amended by that certain Second Amendment to Lease dated April 29, 1996
(the "Second Amendment") (the Original Lease, as amended by the First Amendment
and the Second Amendment is collectively referred to as the "Lease"), pursuant
to which Tenant leased that certain premises located on the fourth (4th) floor
and known as Suite Number 430 (the "Original Premises") and on the third (3rd)
floor and known as Suite Number 300 (the "Additional Premises") and on the first
(1st) floor and known as Suite Number 100 (the "Expansion Premises") of the
building located at 2100 Reston Parkway, Reston, Virginia (the "Building"), said
Original Premises, Additional Premises and Expansion Premises containing in the
aggregate approximately 39,344 rentable square feet (collectively, the "Demised
Premises");

            WHEREAS, Landlord and Tenant desire to amend the Lease (i) to
increase the size of the Demised Premises; and (ii) to amend certain terms and
conditions of the Lease as otherwise set forth herein.

            NOW, THEREFORE, in consideration of the premises and mutual
covenants and agreements herein contained and for other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, the
parties hereto hereby agree to the following:

            1. RECITALS. The recitals set forth above are incorporated herein by
this reference with the same force and effect as if fully set forth hereinafter.

            2. CAPITALIZED TERMS. Capitalized terms not otherwise defined herein
shall have the meaning ascribed to them in the Lease.


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            3.  PREMISES.

            (a) Effective on the date that Landlord substantially completes the
work described in Paragraph 9 hereof (the "New Expansion Premises Commencement
Date"), the Demised Premises shall be increased by approximately One Thousand
Five Hundred Seventy (1,570) rentable square feet of space on the first (1st)
floor of the Building and designated as Suite 103, as shown on Exhibit A-3
attached hereto and made a part hereof (the "New Expansion Premises") to
approximately Forty Thousand Nine Hundred Fourteen (40,914) square feet.

            (b) As of the New Expansion Premises Commencement Date, Section 1.2
of the Lease, as amended by Paragraph 3.b. of the First Amendment, and by
Paragraph 3.b. of the Second Amendment, is amended to read;

            "1.2 PREMISES: Suite Number 103, as shown on Exhibit A-3 of the
            Third Amendment, Suite Number 100, as shown on Exhibit A-2 of the
            Second Amendment, Suite Number 300, as shown on Exhibit A-1 of the
            First Amendment, and Suite Number 430, as shown on Exhibit A of the
            Lease."

            (c) As of the New Expansion Premises Commencement Date, Section 1.3
of the Lease, as amended by Paragraph 3.c. of the First Amendment, and by
Paragraph 3.c. of the Second Amendment, is amended to read:

            "1.3 RENTABLE AREA OF PREMISES: 40,914 rentable square feet,
            comprised of the following: Suite 103, containing 1,570 rentable
            square feet ("New Expansion Premises"), Suite 100 containing 5,642
            rentable square feet ("Expansion Premises"), Suite 300 containing
            25,962 rentable square feet ("Additional Premises"), and Suite 430,
            containing 7,740 rentable square feet ("Original Premises")."

            (d) As of the New Expansion Premises Commencement Date, all
references in the Lease to "Premises" or "Demised Premises" shall, unless
specifically stated otherwise herein, collectively refer to the Original
Premises, the Additional Premises, the Expansion Premises and the New Expansion
Premises.

            4. TERM. The Term of the Lease with respect to the New Expansion
Premises shall be from the New Expansion Premises Commencement Date through
March 31, 2003, unless sooner terminated pursuant to any provision of the Lease
or hereof, it being the intention of the parties that the Term of the Lease with
respect to the New Expansion Premises and the Additional Premises shall be
coterminous.

            5. RENT.

            (a) As of the New Expansion Premises Commencement Date, Section 1.8
of the Lease, as amended by Paragraph 5.a. of the First Amendment and as further


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amended by Paragraph 5.a. of the Second Amendment, shall be deleted in its
entirety and the following Section 1.8 substituted in lieu thereof:


"1.8 Base Rent:               Original Premises:       $11,732.55 per month
                              Additional Premises:     $41,128.14 per month
                              Expansion Premises:      $9,534.98 per month
                              New Expansion
                              Premises:                $3,925.00 per month"


             (b) As of the New Expansion Premises Commencement Date, Paragraph 1
of the Addendum attached to the Lease and made a part thereof, as amended by
Paragraph 5.b. of the First Amendment and as further amended by Paragraph 5.b.
of the Second Amendment, shall be further amended by adding the following at the
end of Paragraph 1 of the Addendum"

   "NEW EXPANSION PREMISES:


                                  Annual
Lease Period (Months)            Base Rent                  Monthly Base Rent
---------------------            ---------                  -----------------

New Expansion Premises
Commencement Date --
end of 1st 12 months         $47,100.00                       $3,925.00
      13 - 24                $48,513.00                       $4,042.75
      25 - 36                $49,968.36                       $4,164.03
   37 -- 3/31/03             $51,467.40 (to be pro-rated)     $4,288.95

            6. BASE RENT PAID UPON EXECUTION. Upon the execution of this Third
Amendment, Tenant shall pay to Landlord the sum of $3,925.00 for payment of the
first full calendar month's Base Rent due under the Lease with respect to the
New Expansion Premises on or after the New Expansion Premises Commencement Date,
in accordance with the terms and conditions set forth in Section 4.1 of the
Lease.

            7. TENANT'S SHARE. As of the New Expansion Premises Commencement
Date, Tenant's Share as set forth in Section 1.11 of the Lease, as amended by
Paragraph 7 of the First Amendment and as further amended by Paragraph 7 of the
Second Amendment, shall be deleted in its entirety and the following substituted
in lieu thereof:



"1.11 TENANT'S SHARE:              Original Premises:                    4.92%.
                                   Additional Premises                   16.52%
                                   Expansion Premises                    3.59%
                                   New Expansion Premises                0.99%"





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            8. PARKING. As of the New Expansion Premises Commencement Date,
Section 1.13 of the Lease, as amended by Paragraph 8 of the First Amendment, and
as further amended by Paragraph 8 of the Second Amendment, shall be deleted in
its entirety and the following Section 1.13 substituted in lieu thereof:

               "1.13 NUMBER OF PARKING SPACES:

               Original Premises:  Reserved:      None;          Unreserved: 28
               Additional Premises:Reserved:      None;          Unreserved: 93
               Expansion Premises: Reserved:      None;          Unreserved: 20
               New Expansion
                Premises:          Reserved:      None;          Unreserved: 5"

            9. OPERATING EXPENSES INCREASES. Effective on the New Expansion
Premises Commencement Date, in addition to the payment of Operating Expense
increases for the Original Premises, the Additional Premises and the Expansion
Premises as set forth in Section 4.2 of the Lease, as amended by Paragraph 9 of
the First Amendment and Paragraph 9 of the Second Amendment, Tenant shall pay
Landlord for increases in Operating Expenses with respect to the New Expansion
Premises. The Base Year on which the increases in Operating Expenses is
calculated with respect to the New Expansion Premises shall be the calendar year
1999. The Base Year on which the increases in Operating Expenses is calculated
with respect to the Original Premises, the Additional Premises and the Expansion
Premises shall be 1995.

            10. TENANT IMPROVEMENTS.

            (a) Tenant acknowledges that all obligations of Landlord pursuant to
Paragraph 10 of the Second Amendment pertaining to the Original Premises and the
Additional Premises have been met.

            (b) Landlord, at Landlord's sole cost and expense, shall install
new building standard carpeting throughout the New Expansion Premises. Except as
provided in this Paragraph 11, Landlord shall have no further obligation to make
any improvements to the Premises for Tenant.

            11. NOTICES. Landlord and Tenant's addresses for notices set forth
in Section 1.17 of the Lease are hereby amended as follows:

            "Landlord:          Gateway Virginia Properties, Inc.
                                c/o Insignia/ESG, Inc.
                                1015 Fifteenth Street, N.W., Suite 1000
                                Washington, DC 20005
                                Attention: Mr. D. Eric Forshee


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            With a copy to:               TA Associates Realty
                                          28 State Street
                                          Boston, MA 02109
                                          Attention:  Mr. Henry G. Brauer"


            12. BROKERS. Tenant represents and warrants to Landlord that Tenant
has not had any dealings or entered into any agreements with any person, entity,
realtor, broker, agent or finder in connection with the negotiation of this
Third Amendment other than Staubach Company and Insignia/ESG, Inc.
(collectively, the "Brokers"). Landlord shall pay a commission to the Brokers in
accordance with the terms of a separate agreement between Landlord and the
Brokers. Tenant shall indemnify and hold Landlord harmless from and against any
loss, claim, damage, expense (including costs of suit and reasonable attorneys'
fees) or liability for any compensation, commission or charges claimed by any
other realtor, broker, agent or finder claiming to have dealt with Tenant in
connection with this Third Amendment.

            13. REAFFIRMATION OF TERMS. Except as expressly modified hereby, all
of the terms, covenants and provisions of the Lease are hereby confirmed and
ratified and shall remain unchanged and in full force and effect.

            14. REPRESENTATIONS. Tenant hereby represents and warrants to
Landlord that to the best of Tenant's knowledge Tenant: (i) is not in default of
any of its obligations under the Lease and that such Lease is valid, binding and
enforceable in accordance with its terms, (ii) has full power and authority to
execute and perform this Third Amendment, and (iii) has taken all action
necessary to authorize the execution and performance of this Third Amendment.

            15. COUNTERPART COPIES. This Third Amendment may be executed in two
or more counterpart copies, each of which shall be deemed to be an original and
all of which counterparts shall have the same force and effect as if the parties
hereto had executed a single copy of this Third Amendment.






                         [signatures on following page]


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            IN WITNESS WHEREOF, Landlord and Tenant have executed this Third
Amendment as of the day and year first above written.

                             LANDLORD:

                             GATEWAY VIRGINIA PROPERTIES, INC., a
                             California corporation
                             T A Realty Corp. as Agent

                             By: /s/  HENRY G. BRAUER
                                ----------------------------------

                             Its:       Henry G. Brauer
                                ----------------------------------
                                        Regional Director
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                             TENANT:

                             CYBERCASH, INC.,
                             a Delaware corporation


                             By: /s/ MARIA C. IZURIETA
                                ----------------------------------

                             Its: VP Finance & Administration
                                ----------------------------------




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