Document:

<PAGE>

                             STANDARD OFFICE LEASE

                                 BY AND BETWEEN

                       ARDEN REALTY LIMITED PARTNERSHIP,

                        A MARYLAND LIMITED PARTNERSHIP,

                                  AS LANDLORD,

                                      AND

                       C-BRIDGE INTERNET SOLUTIONS, INC.,

                            A DELAWARE CORPORATION,

                                   AS TENANT

                                   SUITE 425

                              HOWARD HUGHES TOWER
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                               TABLE OF CONTENTS
                               -----------------

                                                              Page
                                                              ----

ARTICLE 1     BASIC LEASE PROVISIONS.........................   1

ARTICLE 2     TERM/PREMISES..................................   2

ARTICLE 3     RENTAL.........................................   2
     (a)      Basic Rental...................................   2
     (b)      Increase in Direct Costs.......................   2
     (c)      Definitions....................................   3
     (d)      Determination of Payment.......................   5

ARTICLE 4     SECURITY DEPOSIT...............................   6
     (a)      Security Deposit...............................   6
     (b)      Additional Security Deposit....................   7

ARTICLE 5     HOLDING OVER...................................   9

ARTICLE 6     PERSONAL PROPERTY TAXES........................   9

ARTICLE 7     USE............................................   9

ARTICLE 8     CONDITION OF PREMISES..........................  10

ARTICLE 9     REPAIRS AND ALTERATIONS........................  10

ARTICLE 10    LIENS..........................................  11

ARTICLE 11    PROJECT SERVICES...............................  12

ARTICLE 12    RIGHTS OF LANDLORD.............................  13

ARTICLE 13    INDEMNITY; EXEMPTION OF LANDLORD FROM LIABILITY  14
     (a)      Indemnity......................................  14
     (b)      Exemption of Landlord from Liability...........  14

ARTICLE 14    INSURANCE......................................  14
     (a)      Tenant's Insurance.............................  14
     (b)      Form of Policies...............................  15
     (c)      Landlord's Insurance...........................  15
     (d)      Waiver of Subrogation..........................  15
     (e)      Compliance with Law............................  15

ARTICLE 15    ASSIGNMENT AND SUBLETTING......................  16

ARTICLE 16    DAMAGE OR DESTRUCTION..........................  17

ARTICLE 17    SUBORDINATION..................................  18

ARTICLE 18    EMINENT DOMAIN.................................  19

ARTICLE 19    DEFAULT........................................  19
     (a)      Tenant's Default...............................  19
     (b)      Landlord's Default.............................  20

ARTICLE 20    REMEDIES.......................................  20

ARTICLE 21    TRANSFER OF LANDLORD'S INTEREST................  21

ARTICLE 22    BROKER.........................................  21

ARTICLE 23    PARKING........................................  22

ARTICLE 24    WAIVER.........................................  22

                                       1
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ARTICLE 25    ESTOPPEL CERTIFICATE...........................  23

ARTICLE 26    LIABILITY OF LANDLORD..........................  23

ARTICLE 27    INABILITY TO PERFORM...........................  24

ARTICLE 28    HAZARDOUS WASTE................................  24

ARTICLE 29    SURRENDER OF PREMISES; REMOVAL OF PROPERTY.....  25

ARTICLE 30    MISCELLANEOUS..................................  26
     (a)      Severability; Entire Agreement.................  26
     (b)      Attorneys' Fees; Waiver of Jury Trial..........  26
     (c)      Time of Essence................................  26
     (d)      Headings; Joint and Several....................  26
     (e)      Reserved Area..................................  26
     (f)      NO OPTION .....................................  26
     (g)      Use of Project Name; Improvements..............  26
     (h)      Rules and Regulations..........................  27
     (i)      Quiet Possession...............................  27
     (j)      Rent...........................................  27
     (k)      Successors and Assigns.........................  27
     (l)      Notices........................................  27
     (m)      Access.........................................  27
     (n)      Right of Landlord to Perform...................  27
     (o)      Access, Changes in Project, Facilities, Name...  27
     (p)      Signing Authority..............................  28
     (q)      Intentionally Omitted..........................  28
     (r)      Substitute Premises ...........................  28
     (s)      Survival of Obligations........................  28
     (t)      Confidentiality................................  28
     (u)      Governing Law..................................  28
     (v)      Exhibits and Addendum..........................  28

ARTICLE 31    OPTION TO EXTEND...............................  28
     (a)      Option Right...................................  28
     (b)      Option Rent....................................  29
     (c)      Exercise of Option.............................  29

ARTICLE 32    DIRECTORY......................................  29

     Exhibit "A"  Premises
     Exhibit "B"  Rules and Regulations
     Exhibit "C"  Notice of Lease Term Dates and Tenant's Proportionate Share
     Exhibit "D"  Tenant Work Letter
     Exhibit "E"  Letter of Credit

                                       2
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                                     INDEX
                                     -----

                                                        Page(s)
                                                        -------

Abatement Event.....................................         13
Abatement Notice....................................         13
Abatement Period....................................          2
ADA.................................................          4
Additional Rent.....................................          3
Additional Security Deposit.........................          7
Alterations.........................................         10
Approved Working Drawings...........................  Exhibit D
Architect...........................................  Exhibit D
Base Year...........................................          1
Base, Shell and Core................................  Exhibit D
Basic Rental........................................          1
Brokers.............................................          1
Claims..............................................         14
Code................................................  Exhibit D
Commencement Date...................................          1
Construction Drawings...............................  Exhibit D
Contractor..........................................  Exhibit D
Cosmetic Alterations................................         11
Cost Proposal.......................................  Exhibit D
Cost Proposal Delivery Date.........................  Exhibit D
Damage Repair Estimate..............................         17
Direct Costs........................................          3
Eligibility Period..................................         13
Engineers...........................................  Exhibit D
Estimate............................................          5
Estimate Statement..................................          5
Estimated Excess....................................          5
Event of Default....................................         19
Excess..............................................          5
Expiration Date.....................................          1
Final Space Plan....................................  Exhibit D
Final Working Drawings..............................  Exhibit D
First Month's Rent..................................          2
Force Majeure.......................................         24
Hazardous Material..................................         24
Improvement Allowance...............................  Exhibit D
Improvement Allowance Items.........................  Exhibit D
Improvements........................................  Exhibit D
Interest Notice.....................................         29
Landlord............................................          1
Landlord Supervision Fee............................  Exhibit D
Laws................................................         25
Lease...............................................          1
Lease Year..........................................          2
Market Rent.........................................         29
Operating Costs.....................................          3
Option..............................................         28
Option Rent.........................................         29
Option Rent Notice..................................         29
Option Term.........................................         29
Original Tenant.....................................         28
Over-Allowance Amount...............................  Exhibit D
Parking Passes......................................          1
Permits.............................................  Exhibit D
Permitted Assignee..................................         29
Permitted Use.......................................          1
Premises............................................          1
Project.............................................          1

                                       3
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Real Property.......................................          3
Reduction Date......................................          7
Representative......................................         23
Review Period.......................................          6
Security Deposit....................................       1, 6
Specifications......................................  Exhibit D
Square Footage......................................          1
Standard Improvement Package........................  Exhibit D
Statement...........................................          6
Substantial Completion..............................  Exhibit D
Tax Costs...........................................          3
Tenant..............................................          1
Tenant Delays.......................................  Exhibit D
Tenant Improvements.................................         10
Tenant's Acceptance.................................         29
Tenant's Proportionate Share........................          1
Term................................................          1
Time Deadlines......................................  Exhibit D
Transfer............................................         17
Transfer Premium....................................         17
Transferee..........................................         17

                                       4
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                             STANDARD OFFICE LEASE
                             ---------------------

     This Standard Office Lease ("LEASE") is made and entered into as of the
11th day of May, 2000, by and between ARDEN REALTY LIMITED PARTNERSHIP, a
Maryland limited partnership ("LANDLORD"), and C-BRIDGE INTERNET SOLUTIONS,
INC., a Delaware corporation ("TENANT").

     Landlord hereby leases to Tenant and Tenant hereby leases from Landlord the
premises described as Suite No. 425, as designated on the plan attached hereto
and incorporated herein as Exhibit "A" ("PREMISES"), of the project ("PROJECT")
now known as Howard Hughes Tower whose address is 6701 Center Drive West, Los
Angeles, California 90045 for the Term and upon the terms and conditions
hereinafter set forth, and Landlord and Tenant hereby agree as follows:

                                   ARTICLE 1
                                   ---------

                             BASIC LEASE PROVISIONS
                             ----------------------
<TABLE>
<CAPTION>
<C>           <C>                                     <S>
A.            TERM:                                   The period from the Commencement Date through
                                                      the Expiration Date.

              Commencement Date:                      May 11, 2000.

              Expiration Date:                        July 31, 2005 (subject to adjustment as
                                                      provided in Article 2 below).

B.            SQUARE FOOTAGE:                         10,064 rentable (8,867 usable) square feet

C.            BASIC RENTAL:
</TABLE>
<TABLE>
<CAPTION>
                                        Annual           Monthly           Monthly Basic Rental
                 Lease Months*       Basic Rental     Basic Rental       Per Rentable Square Foot
              --------------------  ---------------  ---------------  -------------------------------
<S>           <C>                   <C>              <C>              <C>
                    1-12             $326,073.60       $27,172.80                 $2.70
                   13-24             $332,112.00       $27,676.00                 $2.75
                   25-36             $338,150.40       $28,179.20                 $2.80
                   37-48             $344,188.80       $28,682.40                 $2.85
                   49-60             $350,227.20       $29,185.60                 $2.90
</TABLE>
*Commencing after expiration of the Abatement Period.
<TABLE>
<CAPTION>
<C>          <C>                                     <S>

D.            BASE YEAR:                             2000

E.            TENANT'S PROPORTIONATE SHARE:          3.21%

F.            SECURITY DEPOSIT:                      A Security Deposit of $29,185.60 shall be due
                                                     and payable by Tenant to Landlord upon Tenant's
                                                     execution of this Lease, together with an
                                                     Additional Security Deposit in the amount of
                                                     $364,558.58 as provided in Section 4(b) hereof.

G.            PERMITTED USE:                         General office use.

H.            BROKERS:                               Grubb & Ellis

I.            PARKING PASSES:                        Tenant shall have the use of two point seven
                                                     (2.7) unreserved parking passes for each 1,000
                                                     usable square feet contained in the Premises,
                                                     which equals twenty-four (24) passes, at the
                                                     rate provided in Article 23 hereof.
</TABLE>
<PAGE>

<TABLE>
<CAPTION>
<C>           <C>                                    <S>
J.            FIRST MONTH'S RENT:                    The first full month's rent of $27,172.80 shall
                                                     be due and payable by Tenant to Landlord upon
                                                     Tenant's execution of this Lease.
</TABLE>
                                   ARTICLE 2
                                   ---------

                                 TERM/PREMISES
                                 -------------

     The Term of this Lease shall commence on the Commencement Date as set forth
in Article 1.A. of the Basic Lease Provisions and shall, subject to Tenant's
exercise of the Option set forth in Article 31 hereof, end on the Expiration
Date set forth in Article 1.A. of the Basic Lease Provisions.  Notwithstanding
the fact that the Commencement Date has occurred, Tenant shall not be
responsible for the payment of Basic Rental during the period ("ABATEMENT
PERIOD") from the Commencement Date until the earlier of (i) the date Tenant
first commences to conduct business in the Premises and (ii) date of Substantial
Completion of Improvements in the Premises.  For purposes of this Lease, the
term "LEASE YEAR" shall mean each consecutive twelve (12) month period during
the Lease Term, with the first Lease Year commencing on the day after the date
of expiration of the Abatement Period; however, (a) if the date of expiration of
the Abatement Period falls on a day other than the last day of a calendar month,
the first Lease Year shall end on the last day of the eleventh (11th) month
after the date of expiration of the Abatement Period and the second (2nd) and
each full calendar succeeding Lease Year shall commence on the first day of the
next calendar month, and (b) the last Lease Year shall end on the Expiration
Date.  As of the date of this Lease, the parties anticipate the date of
Substantial Completion of the Improvements in the Premises will be July 31,
2000.  However, if the actual date of expiration of the Abatement Period is
other than July 31, 2000, the Expiration Date shall be revised to be the date
which is the fifth (5th) anniversary of the date of expiration of the Abatement
Period; provided, however, that if the date of expiration of the Abatement
Period is a date other than the last day of a month, the Expiration Date shall
be the last day of the month which is sixty (60) months after the month in which
the date of expiration of the Abatement Period falls, unless extended or earlier
terminated pursuant to this Lease.  Any such revision to the Expiration Date
shall be memorialized in the Commencement Letter.  If Landlord is unable to
deliver possession of the Premises to Tenant on or before the anticipated date
of expiration of the Abatement Period, Landlord shall not be subject to any
liability for its failure to do so, and such failure shall not affect the
validity of this Lease nor the obligations of Tenant hereunder.  Landlord and
Tenant hereby stipulate that the Premises contains the number of square feet
specified in Article 1.B. of the Basic Lease Provisions.  Landlord may deliver
to Tenant a Commencement Letter in a form substantially similar to that attached
hereto as Exhibit "C", which Tenant shall execute and return to Landlord within
five (5) days of receipt thereof.  Failure of Tenant to timely execute and
deliver the Commencement Letter shall constitute acknowledgment by Tenant that
the statements included in such notice are true and correct, without exception.

                                   ARTICLE 3
                                   ---------

                                    RENTAL
                                    ------

   (a)  Basic Rental. Commencing upon expiration of the Abatement Period, Tenant
agrees to pay to Landlord during the Term hereof, at Landlord's office or to
such other person or at such other place as directed from time to time by
written notice to Tenant from Landlord, the initial monthly and annual sums as
set forth in Article 1.C of the Basic Lease Provisions, payable in advance on
the first day of each calendar month, without demand, setoff or deduction except
as otherwise expressly provided in this Lease, and in the event this Lease
commences or the date of expiration of this Lease occurs other than on the first
day or last day of a calendar month, the rent for such month shall be prorated.
Notwithstanding the foregoing, the first full month's rent shall be paid to
Landlord in accordance with Article 1.J. of the Basic Lease Provisions.

   (b)  Increase in Direct Costs. The term "BASE YEAR" means the calendar year
set forth in Article 1.D. of the Basic Lease Provisions. If, in any calendar
year during the Term of this Lease, the "Direct Costs" (as hereinafter defined)
paid or incurred by Landlord shall be higher than the Direct Costs for the Base
Year, Tenant shall pay an additional sum for such and each subsequent calendar
year equal to the product of the amount set forth in Article 1.E. of the Basic
Lease Provisions multiplied by such increased amount of "Direct Costs." In the
event either the

                                      -2-
<PAGE>

Premises and/or the Project is expanded or reduced, then Tenant's Proportionate
Share shall be appropriately adjusted, and as to the calendar year in which such
change occurs, Tenant's Proportionate Share for such year shall be determined on
the basis of the number of days during that particular calendar year that such
Tenant's Proportionate Share was in effect. In the event this Lease shall
terminate on any date other than the last day of a calendar year, the additional
sum payable hereunder by Tenant during the calendar year in which this Lease
terminates shall be prorated on the basis of the relationship which the number
of days which have elapsed from the commencement of said calendar year to and
including said date on which this Lease terminates bears to three hundred sixty
(360). Any and all amounts due and payable by Tenant pursuant to Article
3(b),(c) and (d) hereof shall be deemed "ADDITIONAL RENT" and Landlord shall be
entitled to exercise the same rights and remedies upon default in these payments
as Landlord is entitled to exercise with respect to defaults in monthly Basic
Rental payments.

   (c)  Definitions.  As used herein the term "DIRECT COSTS" shall mean the
sum of the following:

        (i) "TAX COSTS", which shall mean any and all real estate taxes and
other similar charges on real property or improvements, assessments, water and
sewer charges, and all other charges assessed, reassessed or levied upon the
Project and appurtenances thereto and the parking or other facilities thereof,
or the real property thereunder (collectively the "REAL PROPERTY") or
attributable thereto or on the rents, issues, profits or income received or
derived therefrom which are assessed, reassessed or levied by the United States,
the State of California or any local government authority or agency or any
political subdivision thereof, and shall include Landlord's reasonable legal
fees, costs and disbursements incurred in connection with proceedings for
reduction of Tax Costs or any part thereof; provided, however, if at any time
after the date of this Lease the methods of taxation now prevailing shall be
altered so that in lieu of or as a supplement to or a substitute for the whole
or any part of any Tax Costs, there shall be assessed, reassessed or levied (a)
a tax, assessment, reassessment, levy, imposition or charge wholly or partially
on the rents, or (b) a tax, assessment, reassessment, levy (including but not
limited to any municipal, state or federal levy), imposition or charge measured
by or based in whole or in part upon the Real Property and imposed upon
Landlord, or (c) a license fee measured by the rent payable under this Lease,
then all such taxes, assessments, reassessments or levies or the part thereof so
measured or based, shall be deemed to be included in the term "Direct Costs." In
no event shall Tax Costs included in Direct Costs for any year subsequent to the
Base Year be less than the amount of Tax Costs included in Direct Costs for the
Base Year. In addition, when calculating Tax Costs for the Base Year, special
assessments shall only be deemed included in Tax Costs for the Base Year to the
extent that such special assessments are included in Tax Costs for the
applicable subsequent calendar year during the Term. Notwithstanding anything to
the contrary contained in this Section 3(c)(i), there shall be excluded from Tax
Costs (i) all excess profit taxes, franchise taxes, gift taxes, capital stock
taxes, inheritance taxes and succession taxes, estates taxes, federal and state
income taxes, and other taxes to the extent applicable to Landlord's general or
net income (as opposed to rents or receipts attributable to the operations of
the Project), (ii) any items included as Operating Costs, and (iii) any items
paid by Tenant under Article 6 of this Lease.

        (ii) "OPERATING COSTS", which shall mean all costs and expenses incurred
by Landlord in connection with the maintenance, operation, replacement,
ownership and repair of the Project, the equipment, the intrabuilding network
cable, adjacent walks, malls and landscaped and common areas and the parking
structure, areas and facilities of the Project, including, but not limited to,
reasonable salaries, wages, medical, surgical and general welfare benefits and
pension payments, payroll taxes, fringe benefits, employment taxes, workers'
compensation, uniforms and dry cleaning thereof for all persons who perform
duties connected with the operation, maintenance and repair of the Project, its
equipment, the intrabuilding network cable and the adjacent walks and landscaped
areas, including janitorial, gardening, security, parking, operating engineer,
elevator, painting, plumbing, electrical, carpentry, heating, ventilation, air
conditioning, window washing, hired services, a reasonable allowance for
depreciation of the cost of acquiring or the rental expense of personal property
used in the maintenance, operation and repair of the Project, accountant's fees
incurred in the preparation of rent adjustment statements, reasonable legal
fees, real estate tax consulting fees, personal property taxes on property used
in the maintenance and operation of the Project, fees, costs, expenses or dues
payable pursuant to the terms of any covenants, conditions or restrictions or
owners' association pertaining to the Project, capital expenditures incurred to
effect economies of operation of, or

                                      -3-
<PAGE>

stability of services to, the Project and capital expenditures required by
government regulations, laws, or ordinances not in effect as of the Commencement
Date; the cost of all charges for electricity, gas, water and other utilities
furnished to the Project, including any taxes thereon; the cost of all charges
for fire and extended coverage, liability and all other insurance for the
Project carried by Landlord; the cost of all building and cleaning supplies and
materials; the cost of all charges for cleaning, maintenance and service
contracts and other services with independent contractors and administration
fees; a reasonable property management fee (which fee may be imputed if Landlord
has internalized management or otherwise acts as its own property manager) and
license, permit and inspection fees relating to the Project. In the event,
during any calendar year, the Project is less than ninety-five percent (95%)
occupied at all times, Operating Costs shall be adjusted to reflect the
Operating Costs of the Project as though ninety-five percent (95%) were occupied
at all times, and the increase or decrease in the sums owed hereunder shall be
based upon such Operating Costs as so adjusted. In no event shall costs for any
item of utilities included in Direct Costs for any year subsequent to the Base
Year be less than the amount included in Direct Costs for the Base Year for such
utility item. Notwithstanding anything to the contrary set forth in this Article
3, when calculating Operating Costs for the Base Year, Operating Costs shall
exclude (a) market-wide labor-rate increases due to extraordinary circumstances
including, but not limited to, boycotts and strikes, (b) utility rate increases
due to extraordinary circumstances including, but not limited to, conservation
surcharges, boycotts, embargoes or other shortages, and (c) amortization of any
capital items including, but not limited to, capital improvements, capital
repairs and capital replacements (including such amortized costs where the
actual improvement, repair or replacement was made in prior years).

     Notwithstanding anything above to the contrary, Operating Costs shall not
include (1) the cost of providing any service directly to and paid directly by
any tenant (outside of such tenant's Direct Cost payments); (2) the cost of any
items for which Landlord is reimbursed by insurance proceeds, condemnation
awards, a tenant of the Project, or otherwise to the extent so reimbursed; (3)
any real estate brokerage commissions or other costs incurred in procuring
tenants, or any fee in lieu of commission; (4) depreciation, amortization of
principal and interest on mortgages or ground lease payments (if any); (5) costs
of items considered capital repairs, replacements, improvements and equipment
under generally accepted accounting principles consistently applied except as
expressly included in Operating Costs pursuant to the definition above; (6)
costs incurred by Landlord due to the violation by Landlord or any tenant of the
terms and conditions of any lease of space in the Project or any law, code,
regulation, ordinance or the like; (7) Landlord's general corporate overhead and
general and administrative expenses; (8) any compensation paid to clerks,
attendants or other persons in commercial concessions operated by Landlord
(other than in the parking facility for the Project); (9) costs incurred in
connection with upgrading the Project to comply with disability, life, seismic,
fire and safety codes, ordinances, statutes, or other laws in effect prior to
the Commencement Date, including, without limitation, the Americans with
Disabilities Act ("ADA"), including penalties or damages incurred due to such
non-compliance; (10) bad debt expenses and interest, principal, points and fees
on debts (except in connection with the financing of items which may be included
in Operating Costs) or amortization on any ground lease, mortgage or mortgages
or any other debt instrument encumbering the Project (including the land on
which the Project is situated); (11) marketing costs, including leasing
commissions, attorneys' fees in connection with the negotiation and preparation
of letters, deal memos, letters of intent, leases, subleases and/or assignments,
space planning costs, and other costs and expenses incurred in connection with
lease, sublease and/or assignment negotiations and transactions with present or
prospective tenants or other occupants of the Project, including attorneys' fees
and other costs and expenditures incurred in connection with disputes with
present or prospective tenants or other occupants of the Project; (12) real
estate brokers' leasing commissions; (13) costs, including permit, license and
inspection costs, incurred with respect to the installation of other tenants' or
occupants' improvements made for tenants or other occupants in the Project or
incurred in renovating or otherwise improving, decorating, painting or
redecorating vacant space for tenants or other occupants in the Project; (14)
any costs expressly excluded from Operating Costs elsewhere in this Lease; (15)
costs of any items (including, but not limited to, costs incurred by Landlord
for the repair of damage to the Project) to the extent Landlord receives
reimbursement from insurance proceeds or from a third party (except that any
deductible amount under any insurance policy shall be included within Operating
Costs); (16) rentals and other related expenses for leasing an HVAC system,
elevators, or other items (except when needed in connection with normal repairs
and maintenance of the Project) which if purchased, rather than rented, would
constitute a capital improvement not included in Operating Costs pursuant to
this Lease; (17) depreciation,

                                      -4-
<PAGE>

amortization and interest payments, except as specifically included in Operating
Costs pursuant to the terms of this Lease and except on materials, tools,
supplies and vendor-type equipment purchased by Landlord to enable Landlord to
supply services Landlord might otherwise contract for with a third party, where
such depreciation, amortization and interest payments would otherwise have been
included in the charge for such third party's services, all as determined in
accordance with generally accepted accounting principles, consistently applied,
and when depreciation or amortization is permitted or required, the item shall
be amortized over its reasonably anticipated useful life; (18) costs incurred by
Landlord for alterations (including structural additions), repairs, equipment
and tools which are of a capital nature and/or which are considered capital
improvements or replacements under generally accepted accounting principles,
consistently applied, except as specifically included in Operating Costs
pursuant to the terms of this Lease; (19) expenses in connection with services
or other benefits which are not offered to Tenant or for which Tenant is charged
for directly but which are provided to another tenant or occupant of the
Project, without charge; (20) electric power costs or other utility costs for
which any tenant directly contracts with the local public service company (but
Landlord shall have the right to "gross up" as if such space was vacant); (21)
costs incurred in connection with the operation of retail stores selling
merchandise and restaurants in the Project to the extent such costs are in
excess of the costs Landlord reasonably estimates would have been incurred had
such space been used for general office use; (22) costs (including in connection
therewith all attorneys' fees and costs of settlement, judgments and/or payments
in lieu thereof) arising from claims, disputes or potential disputes in
connection with potential or actual claims litigation or arbitrations pertaining
to Landlord and/or the Project, other than such claims or disputes with vendors
respecting any services or equipment used in the operation of the Building by
Landlord (provided that any amounts received by Landlord as awards or payments
on settlement of such claims shall be applied first to offset the costs
thereof); (23) costs associated with the operation of the business of the
partnership which constitutes Landlord as the same are distinguished from the
costs of operation of the Project; (24) costs incurred in connection with the
original construction of the Project; (25) costs of correcting defects in or
inadequacy of the initial design or construction of the Project; and (26) costs
incurred to (i) comply with laws relating to the removal of any "Hazardous
Material," as that term is defined in Article 28 of this Lease, which was in
existence on the Project prior to the Commencement Date, and (ii) to remove,
remedy, contain, or treat any Hazardous Material, which Hazardous Material is
brought onto the Project after the date hereof by Landlord or any other tenant
of the Project.

   (d)  Determination of Payment.

        (i) If for any calendar year ending or commencing within the Term,
Tenant's Proportionate Share of Direct Costs for such calendar year exceeds
Tenant's Proportionate Share of Direct Costs for the Base Year, then Tenant
shall pay to Landlord, in the manner set forth in Sections 3(d)(ii) and (iii),
below, and as additional rent, an amount equal to the excess (the "EXCESS").

        (ii) Landlord shall give Tenant a yearly expense estimate statement (the
"ESTIMATE STATEMENT") which shall set forth Landlord's reasonable estimate (the
"ESTIMATE") of what the total amount of Direct Costs for the then-current
calendar year shall be and the estimated Excess (the "ESTIMATED EXCESS") as
calculated by comparing Tenant's Proportionate Share of Direct Costs for such
calendar year, which shall be based upon the Estimate, to Tenant's Proportionate
Share of Direct Costs for the Base Year. The failure of Landlord to timely
furnish the Estimate Statement for any calendar year shall not preclude Landlord
from enforcing its rights to collect any Estimated Excess under this Article 3.
If pursuant to the Estimate Statement an Estimated Excess is calculated for the
then-current calendar year, Tenant shall pay, with its next installment of
Monthly Basic Rental due, a fraction of the Estimated Excess for the then-
current calendar year (reduced by any amounts paid pursuant to the last sentence
of this Section 3(d)(ii)). Such fraction shall have as its numerator the number
of months which have elapsed in such current calendar year to the month of such
payment, both months inclusive, and shall have twelve (12) as its denominator.
Until a new Estimate Statement is furnished, Tenant shall pay monthly, with the
Monthly Basic Rental installments, an amount equal to one-twelfth (1/12) of the
total Estimated Excess set forth in the previous Estimate Statement delivered by
Landlord to Tenant.

        (iii) In addition, Landlord shall use reasonable efforts to give to
Tenant on or before the first day of April (but in any event on or before the
first day of July) following the end

                                      -5-
<PAGE>

of each calendar year, a statement (the "STATEMENT") which shall state the
Direct Costs incurred or accrued for such preceding calendar year, and which
shall indicate the amount, if any, of the Excess. Upon receipt of the Statement
for each calendar year during the Term, if amounts paid by Tenant as Estimated
Excess are less than the actual Excess as specified on the Statement, Tenant
shall pay, with its next installment of Monthly Basic Rental due, the full
amount of the Excess for such calendar year, less the amounts, if any, paid
during such calendar year as Estimated Excess. If, however, the Statement
indicates that amounts paid by Tenant as Estimated Excess are greater than the
actual Excess as specified on the Statement, such overpayment shall be credited
against Tenant's next installments of Estimated Excess. The failure of Landlord
to timely furnish the Statement for any calendar year shall not prejudice
Landlord from enforcing its rights under this Article 3. Even though the Term
has expired and Tenant has vacated the Premises, when the final determination is
made of Tenant's Proportionate Share of the Direct Costs for the calendar year
in which this Lease terminates, if an Excess is present, Tenant shall
immediately pay to Landlord an amount as calculated pursuant to the provisions
of this Article 3(d). The provisions of this Section 3(d)(iii) shall survive the
expiration or earlier termination of the Term.

        (iv) Within one hundred twenty (120) days after receipt of a Statement
by Tenant ("REVIEW PERIOD"), if Tenant disputes the amount set forth in the
Statement, Tenant's employees or an independent certified public accountant
(which accountant is a member of a nationally or regionally recognized
accounting firm and is hired on a non-contingency fee basis), designated by
Tenant, may, after reasonable notice to Landlord and at reasonable times,
inspect Landlord's records at Landlord's offices, provided that Tenant is not
then in default after expiration of all applicable cure periods of any
obligation under this Lease (including, but not limited to, the payment of the
amount in dispute) and provided further that Tenant and such accountant or
representative shall, and each of them shall use their commercially reasonable
efforts to cause their respective agents and employees to, maintain all
information contained in Landlord's records in strict confidence.
Notwithstanding the foregoing, Tenant shall only have the right to review
Landlord's records one (1) time during any twelve (12) month period. Tenant's
failure to dispute the amounts set forth in any Statement within the Review
Period shall be deemed to be Tenant's approval of such Statement and Tenant,
thereafter, waives the right or ability to dispute the amounts set forth in such
Statement. If after such inspection, but within thirty (30) days after the
Review Period, Tenant notifies Landlord in writing that Tenant still disputes
such amounts, a certification as to the proper amount shall be made in
accordance with Landlord's standard accounting practices, at Tenant's expense,
by an independent certified public accountant reasonably acceptable to Landlord
and Tenant (which shall not be in a firm regularly engaged to provide accounting
services to either Landlord or Tenant) and who is a member of a nationally or
regionally recognized accounting firm, which certification shall be binding upon
Landlord and Tenant. Landlord shall cooperate in good faith with Tenant and the
accountant to show Tenant and the accountant the information upon which the
certification is to be based. However, if such certification by the accountant
proves that the Direct Costs set forth in the Statement were overstated by more
than five percent (5%), then the cost of the accountant and the cost of such
certification shall be paid for by Landlord. Promptly following the parties
receipt of such certification, the parties shall make such appropriate payments
or reimbursements, as the case may be, to each other, as are determined to be
owing pursuant to such certification. Tenant agrees that this section shall be
the sole method to be used by Tenant to dispute the amount of any Direct Costs
payable by Tenant pursuant to the terms of this Lease, and Tenant hereby waives
any other rights at law or in equity relating thereto.

        (v) If the Project is a part of a multi-building development, those
Direct Costs attributable to such development as a whole (and not attributable
solely to any individual building therein) shall be allocated by Landlord to the
Project and to the other buildings within such development on an equitable
basis.

                                   ARTICLE 4
                                   ---------

                                SECURITY DEPOSIT
                                ----------------

   (a) Security Deposit. Tenant has deposited with Landlord the sum set forth in
Article 1.F. of the Basic Lease Provisions as security for the full and faithful
performance of every provision of this Lease to be performed by Tenant (the
"SECURITY DEPOSIT"). If Tenant breaches any provision of this Lease, including
but not limited to the payment of rent, Landlord

                                      -6-
<PAGE>

may use all or any part of this Security Deposit for the payment of any rent or
any other sums in default, or to compensate Landlord for any other loss or
damage which Landlord may suffer by reason of Tenant's default. If any portion
of said Security Deposit is so used or applied, Tenant shall, within twenty (20)
days after written demand therefor, deposit cash with Landlord in an amount
sufficient to restore the Security Deposit to its original amount. Tenant agrees
that Landlord shall not be required to keep the Security Deposit in trust,
segregate it or keep it separate from Landlord's general funds but Landlord may
commingle the Security Deposit with its general funds and Tenant shall not be
entitled to interest on such Security Deposit. At the expiration of the Lease
Term, and provided there exists no default by Tenant hereunder, the Security
Deposit or any balance thereof shall be returned to Tenant (or, unless expressly
provided to the contrary in any assignment documentation, to Tenant's designee),
provided that subsequent to the expiration of this Lease, Landlord may retain
from said Security Deposit (i) an amount reasonably estimated by Landlord to
cover potential Direct Cost reconciliation payments due with respect to the
calendar year in which this Lease terminates or expires (such amount so retained
shall not, in any event, exceed ten percent (10%) of estimated Direct Cost
payments due from Tenant for such calendar year through the date of expiration
or earlier termination of this Lease and any amounts so retained and not applied
to such reconciliation shall be returned to Tenant within thirty (30) days after
Landlord's delivery of the Statement for such calendar year), (ii) any and all
amounts reasonably estimated by Landlord to cover the anticipated costs to be
incurred by Landlord to remove any signage provided to Tenant under this Lease
and to repair any damage caused by such removal (in which case any excess amount
so retained by Landlord shall be returned to Tenant within thirty (30) days
after such removal and repair), and (iii) any and all amounts permitted by law
or this Article 4. Tenant hereby waives the provisions of Section 1950.7 of the
California Civil Code and all other provisions of law, now or hereafter in
effect, to the extent the same are inconsistent with Landlord's right to claim
those sums specified in this Article 4 above and/or those sums reasonably
necessary to compensate Landlord for any other loss or damage, foreseeable or
unforeseeable, caused by the acts or omissions of Tenant or any officer,
employee, agent, contractor or invitee of Tenant.

   (b) Additional Security Deposit. In addition to the Security Deposit set
forth in Section 4(a) above, Tenant shall also deposit with Landlord, an
additional security deposit (the "ADDITIONAL SECURITY DEPOSIT") in the form of
cash or an irrevocable letter of credit as set forth below.

        (i) Cash Deposit. In the event Tenant elects to deposit the Additional
Security Deposit in the form of cash, Tenant shall deposit the sum of Three
Hundred Sixty-Four Thousand Five Hundred Fifty-Eight and 58/100 Dollars
($364,558.58) to Landlord concurrently with Tenant's execution and delivery of
this Lease. Landlord will hold such cash Additional Security Deposit in
accordance with the terms of Article 4(a), above, provided, that so long as
Tenant is not in default hereunder, such cash Additional Security Deposit shall
be reduced on each yearly anniversary of Commencement Date (the "REDUCTION
DATE") by the amount of Seventy-Two Thousand Nine Hundred Eleven and 72/100
Dollars ($72,911.72) which amount shall be promptly paid by Landlord to Tenant.
However, if (i) a default by Tenant occurs under this Lease, or (ii)
circumstances exist that would, with notice or lapse of time, or both,
constitute a default by Tenant, and Tenant has failed to cure such default
within the time period permitted by Section 19 of this Lease or such lesser time
as may remain before the relevant Reduction Date as provided above, the cash
Additional Security Deposit shall not thereafter be reduced unless and until
such default shall have been fully cured pursuant to the terms of this Lease, at
which time the cash Additional Security Deposit may be reduced as hereinabove
described. Any unused portion of the cash Additional Security Deposit shall be
returned to Tenant after the expiration of the Term in accordance with Article
4(a), above.

        (ii) Letter of Credit. As an alternative to Section 4(b)(i) above,
Tenant may elect to provide Landlord with an irrevocable letter of credit. In
the event Tenant elects this option, Tenant shall concurrently with Tenant's
execution of this Lease, deliver to Landlord an unconditional, irrevocable and
renewable letter of credit ("LETTER OF CREDIT") in favor of Landlord in the form
attached hereto as Exhibit "F" (with any changes thereto subject to Landlord's
approval), issued by a bank reasonably satisfactory to Landlord with a branch
located in California, in the principal amount ("STATED AMOUNT") specified
below, as security for the faithful performance and observance by Tenant of the
terms, provisions and conditions of this Lease. Tenant shall pay all expenses,
points and/or fees incurred by Tenant in obtaining the Letter of Credit. The
Stated Amount shall initially be Three Hundred Sixty-Four Thousand Five

                                      -7-
<PAGE>

Hundred Fifty-Eight and 58/100 Dollars ($364,558.58); provided, however, that
upon the dates specified below ("ADJUSTMENT DATES"), the Stated Amount may be
reduced to the following amounts:
<TABLE>
<CAPTION>
     Month        Stated Amount
---------------  ----------------
<S>              <C>
 July 31, 2001     $291,646.86
 July 31, 2002     $218,735.14
 July 31, 2003     $145,823.42
 July 31, 2004     $ 72,911.72
</TABLE>

     However, if (i) a default by Tenant occurs under this Lease, or (ii)
circumstances exist that would, with notice or lapse of time, or both,
constitute a default by Tenant, and Tenant has failed to cure such default
within the time period permitted by Section 19 of this Lease or such lesser time
as may remain before the relevant Adjustment Date as provided above, the Stated
Amount shall not thereafter be reduced unless and until such default shall have
been fully cured pursuant to the terms of this Lease, at which time the Stated
Amount may be reduced as hereinabove described.  The Letter of Credit shall
state that an authorized officer or other representative of Landlord may make
demand on Landlord's behalf for the Stated Amount of the Letter of Credit, or
any portion thereof, and that the issuing bank must immediately honor such
demand, without qualification or satisfaction of any conditions, other than
those set forth in the form letter of credit attached as Exhibit "E" hereto
except the proper identification of the party making such demand.  In addition,
the Letter of Credit shall indicate that it is transferable in its entirety by
Landlord as beneficiary or by any subsequent transferee and that upon receiving
written notice of transfer, and upon presentation to the issuing bank of the
original Letter of Credit, the issuer or confirming bank will reissue the Letter
of Credit naming such transferee as the beneficiary. The Letter of Credit must
remain in effect through September 30, 2005.  In no event shall Landlord make
any demand for payment under the Letter of Credit prior to the occurrence of an
Event of Default under and as defined in this Lease; provided, however, that if
the term of the Letter of Credit held by Landlord will expire prior to the last
day of the Term and it is not extended, or a new Letter of Credit for an
extended period of time is not substituted, within thirty (30) days prior to the
expiration of the Letter of Credit, then Landlord shall be entitled to make
demand for the Stated Amount of said Letter of Credit and, thereafter, to hold
such funds in accordance with this Section 4(b)(ii).  The Letter of Credit and
any such proceeds thereof shall be held by Landlord as security for the faithful
performance by Tenant of all of the terms, covenants and conditions of this
Lease.  If Tenant commits a default with respect to any provision of this Lease,
and such default shall not have been cured prior to the expiration of any
applicable cure period, Landlord may (but shall not be required to) draw upon
all or any portion of the Stated Amount of the Letter of Credit, for the payment
of any sum which is in default, or any other amount which Landlord may spend or
become obligated to spend by reason of Tenant's default or for any loss or
damage which Landlord may suffer by reason of Tenant's default.  If any portion
of the Letter of Credit proceeds are so used or applied, Tenant shall, within
ten (10) days after demand therefor, post an additional Letter of Credit in an
amount to cause the aggregate amount of the unused proceeds and such new Letter
of Credit to equal the Stated Amount required in this Section 4(b)(ii) above.
Landlord may then use, apply, or retain such proceeds and Landlord shall not be
required to keep any proceeds from the Letter of Credit separate from its
general funds.  Should Landlord sell its interest in the Project during the Term
and if the purchaser assumes the obligations of Landlord under this Lease, and
if Landlord deposits with the purchaser thereof the Letter of Credit or any
proceeds of the Letter of Credit, thereupon Landlord shall be discharged from
any further liability with respect to the Letter of Credit and said proceeds.
Any remaining proceeds of the Letter of Credit held by Landlord after expiration
of the Term, after any deductions described in this Section 4(b)(ii) above,
shall be returned to Tenant or, at Landlord's option, to the last assignee of
Tenant's interest hereunder, within thirty (30) days following the expiration of
the Term.

                                      -8-
<PAGE>

                                   ARTICLE 5
                                   ---------

                                  HOLDING OVER
                                  ------------

     Should Tenant, without Landlord's written consent, hold over after
termination of this Lease, Tenant shall become a tenant from month to month,
only upon each and all of the terms herein provided as may be applicable to a
month to month tenancy and any such holding over shall not constitute an
extension of this Lease.  During such holding over, Tenant shall pay in advance,
monthly, Basic Rental at one hundred fifty percent (150%) of the rate in effect
for the last month of the Term of this Lease, in addition to, and not in lieu
of, all other payments required to be made by Tenant hereunder including but not
limited to Tenant's Proportionate Share of any increase in Direct Costs.
Nothing contained in this Article 5 shall be construed as consent by Landlord to
any holding over of the Premises by Tenant, and Landlord expressly reserves the
right to require Tenant to surrender possession of the Premises to Landlord as
provided in this Lease upon the expiration or earlier termination of the Term.
If Landlord notifies Tenant in writing at least thirty (30) days prior to the
Lease Expiration Date that Landlord has a signed proposal from a succeeding
tenant to lease the Premises and if Tenant fails to surrender the Premises upon
the expiration or termination of this Lease, Tenant agrees to indemnify, defend
and hold Landlord harmless from all costs, loss, expense or liability, including
without limitation, claims made by any succeeding tenant and real estate brokers
claims and attorney's fees and costs.

                                   ARTICLE 6
                                   ---------

                            PERSONAL PROPERTY TAXES
                            -----------------------

     Tenant shall pay, prior to delinquency, all taxes assessed against or
levied upon trade fixtures, furnishings, equipment and all other personal
property of Tenant located in the Premises.  In the event any or all of Tenant's
trade fixtures, furnishings, equipment and other personal property shall be
assessed and taxed with property of Landlord, or if the cost or value of any
leasehold improvements in the Premises exceeds the cost or value of a Project-
standard buildout as determined by Landlord and, as a result, real property
taxes for the Project are increased, Tenant shall pay to Landlord its share of
such taxes within ten (10) days after delivery to Tenant by Landlord of a
statement in writing setting forth the amount of such taxes applicable to
Tenant's property or above-standard improvements.  Tenant shall pay directly to
the party or entity entitled thereto all business license fees, gross receipts
taxes and similar taxes and impositions which may from time to time be assessed
against or levied upon Tenant, as and when the same become due and before
delinquency.  Notwithstanding anything to the contrary contained herein, any
sums payable by Tenant under this Article 6 shall not be included in the
computation of "Tax Costs."

                                   ARTICLE 7
                                   ---------

                                      USE
                                      ---

     Tenant shall use and occupy the Premises only for the use set forth in
Article 1.G. of the Basic Lease Provisions and shall not use or occupy the
Premises or permit the same to be used or occupied for any other purpose without
the prior written consent of Landlord, which consent may be given or withheld in
Landlord's sole and absolute discretion, and Tenant agrees that it will use the
Premises in such a manner so as not to interfere with or infringe the rights of
other tenants in the Project.  Tenant shall, at its sole cost and expense,
promptly comply with all laws, statutes, ordinances and governmental regulations
or requirements now in force or which may hereafter be in force relating to or
affecting (i) the condition, use or occupancy of the Premises or the Project
excluding structural changes to the Project not related to Tenant's particular
use of the Premises, and (ii) improvements installed or constructed in the
Premises by or for the benefit of Tenant.  Tenant shall not do or permit to be
done anything which would invalidate or increase the cost of any fire and
extended coverage insurance policy covering the Project and/or the property
located therein and Tenant shall comply with all rules, orders, regulations and
requirements of any organization which sets out standards, requirements or
recommendations commonly referred to by major fire insurance underwriters.
Tenant shall promptly upon demand reimburse Landlord for any additional premium
charges for any such insurance policy assessed or increased by reason of
Tenant's failure to comply with the provisions of this Article.

                                      -9-
<PAGE>

                                   ARTICLE 8
                                   ---------

                             CONDITION OF PREMISES
                             ---------------------

     Landlord represents that Landlord has taken or shall take the necessary
steps to comply with what Landlord reasonably believes are the requirements of
the ADA in effect as of the date of this Lease as it pertains to the common
areas within the Project.  Operating Costs shall not include any costs incurred
by Landlord in connection with upgrading the Project to comply with the
requirements of the ADA that are in effect as of the date of this Lease,
including penalties or damages incurred due to such noncompliance.  The Premises
shall be initially improved as provided in, and subject to, the Tenant Work
Letter attached hereto as Exhibit "D" and made a part hereof.  The existing
leasehold improvements in the Premises as of the date of this Lease, together
with the Improvements (as defined in the Tenant Work Letter) may be collectively
referred to herein as the "TENANT IMPROVEMENTS."  The taking of possession of
the Premises by Tenant shall conclusively establish that the Premises and the
Project were at such time in satisfactory condition subject to compliance with
any obligations in respect of "punch list" items brought to Landlord's attention
in accordance with Section 6.4 of the Tenant Work Letter attached hereto as
Exhibit "D" (and provided that nothing herein contained shall result in a waiver
by Tenant of claims against the Contractor for latent defect not known at the
time of Substantial Completion).  Tenant hereby waives subsection 1 of Section
1932 and Sections 1941 and 1942 of the Civil Code of California or any successor
provision of law.

     Landlord reserves the right from time to time: (i) to install, use,
maintain, repair, replace and relocate for service to the Premises and/or other
parts of the Project pipes, ducts, conduits, wires, appurtenant fixtures, and
mechanical systems, wherever located in the Premises or the Project, (ii) to
alter, close or relocate any facility in the Premises or the Common Areas or
otherwise conduct any of the above activities for the purpose of complying with
a general plan for fire/life safety for the Project or otherwise and (iii) to
comply with any federal, state or local law, rule or order with respect thereto
or the regulation thereof not currently in effect.  Landlord shall attempt to
perform any such work with the least inconvenience to Tenant as possible, but in
no event shall Tenant be permitted to withhold or reduce Basic Rental or other
charges due hereunder as a result of same, make any claim for constructive
eviction or otherwise make claim against Landlord for interruption or
interference with Tenant's business and/or operations.

                                   ARTICLE 9
                                   ---------

                            REPAIRS AND ALTERATIONS
                            -----------------------

     Landlord shall maintain the structural portions of the Project including
the foundation, floor/ceiling slabs, roof, curtain wall, exterior glass,
columns, beams, shafts, stairs, stairwells, elevator cabs and common areas and
shall also maintain and repair the basic mechanical, electrical, lifesafety,
plumbing, sprinkler systems and heating, ventilating and air-conditioning
systems.  Except as expressly provided as Landlord's obligation in this Article
9, Tenant shall keep the Premises in good condition and repair.  All damage or
injury to the Premises or the Project resulting from the act or negligence of
Tenant, its employees, agents or visitors, guests, invitees or licensees or by
the use of the Premises shall be promptly repaired by Tenant, at its sole cost
and expense, to the satisfaction of Landlord; provided, however, that for damage
to the Project as a result of casualty or for any repairs that may impact the
mechanical, electrical, plumbing, heating, ventilation or air-conditioning
systems of the Project, Landlord shall have the right (but not the obligation)
to select the contractor and oversee all such repairs.  Landlord may make any
repairs required by the terms of this Lease to be made by Tenant and which are
not promptly made by Tenant after Tenant's receipt of written notice, if Tenant
shall not commence the making of such repairs within five (5) business days from
receipt of said written notice or if Tenant fails to diligently prosecute said
repairs to completion, and charge Tenant for the cost thereof, which cost shall
be paid by Tenant within five (5) days from invoice from Landlord.  Tenant shall
be responsible for the design and function of all non-standard improvements of
the Premises, whether or not installed by Landlord at Tenant's request.  Tenant
waives all rights to make repairs at the expense of Landlord, or to deduct the
cost thereof from the rent.  Tenant shall make no alterations, changes or
additions in or to the Premises (collectively, "ALTERATIONS") without Landlord's
prior written consent (not to be unreasonably withheld, conditioned or delayed),
and then only by contractors or mechanics approved by Landlord in writing and
upon the approval by Landlord in writing of fully detailed and dimensioned plans
and specifications

                                      -10-
<PAGE>

pertaining to the Alterations in question, to be prepared and submitted by
Tenant at its sole cost and expense. Tenant shall at its sole cost and expense
obtain all necessary approvals and permits pertaining to any Alterations
approved by Landlord. Tenant shall construct such Alterations in a good and
workmanlike manner, in conformance with all applicable federal, state, county
and municipal laws, rules and regulations, pursuant to a valid building permit,
and in conformance with Landlord's construction rules and regulations. If
Landlord, in approving any Alterations, specifies a commencement date therefor,
Tenant shall not commence any work with respect to such Alterations prior to
such date. Notwithstanding anything to the contrary contained herein, Tenant may
make strictly cosmetic changes to the finish work in the Premises (the "COSMETIC
ALTERATIONS") without Landlord's consent, provided that the aggregate cost of
any such alterations does not exceed $25,000 in any twelve (12) month period,
and further provided that such alterations do not (i) require any structural or
other substantial modifications to the Premises, (ii) require any changes to,
nor adversely affect, the systems and equipment of the Project, and (iii) affect
the exterior appearance of the Project. Tenant shall give Landlord at least
fifteen (15) days prior notice of such cosmetic Alterations, which notice shall
be accompanied by reasonably adequate evidence that such changes meet the
criteria contained in this Article 9. Tenant hereby indemnifies, defends and
agrees to hold Landlord free and harmless from all liens and claims of lien, and
all other liability, claims and demands arising out of any work done or material
supplied to the Premises by or at the request of Tenant in connection with any
Alterations. Prior to the commencement of any Alterations, Tenant shall provide
Landlord with evidence that Tenant carries "Builder's All Risk" insurance in an
amount approved by Landlord covering the construction of such Alterations, and
such other insurance as Landlord may reasonably require, it being understood
that all such Alterations shall be insured by Tenant pursuant to Article 14 of
this Lease immediately upon completion thereof. In addition, Landlord may, in
its discretion, require Tenant to obtain a lien and completion bond or some
alternate form of security satisfactory to Landlord in an amount sufficient to
ensure the lien free completion of such Alterations and naming Landlord as a co-
obligee. If permitted Alterations are made, they shall be made at Tenant's sole
cost and expense and shall be and become the property of Landlord, except that
Landlord may, by written notice to Tenant given at least thirty (30) days prior
to the end of the Term, require Tenant at Tenant's expense to remove all
partitions, counters, railings and other Alterations installed by Tenant, and to
repair any damages to the Premises caused by such removal provided that Landlord
shall have notified Tenant that such removal will be required at the end of the
Lease Term which notice shall be given (a) for Alterations requiring the
Landlord's approval, at the time of Landlord's approval, and (b) for Alterations
which do not require Landlord's approval, within five (5) days after Tenant's
request for such a determination. Any and all costs attributable to or related
to the applicable building codes of the city in which the Project is located (or
any other authority having jurisdiction over the Project) arising from Tenants
plans, specifications, improvements, alterations or otherwise shall be paid by
Tenant at its sole cost and expense. With regard to repairs, Alterations or any
other work arising from or related to this Article 9, Landlord shall be entitled
to receive a reasonable administrative/supervision fee (which fee shall vary
depending upon whether or not Tenant orders the work directly from Landlord)
sufficient to compensate Landlord for all overhead, general conditions, fees and
other costs and expenses arising from Landlord's involvement with such work. The
construction of initial improvements to the Premises shall be governed by the
terms of the Tenant Work Letter and not the terms of this Article 9.

                                  ARTICLE 10
                                  ----------

                                     LIENS
                                     -----

     Tenant shall keep the Premises and the Project free from any mechanics'
liens, vendors liens or any other liens arising out of any work performed,
materials furnished or obligations incurred by Tenant, and agrees to defend,
indemnify and hold harmless Landlord from and against any such lien or claim or
action thereon, together with costs of suit and reasonable attorneys' fees
incurred by Landlord in connection with any such claim or action.  Before
commencing any work of alteration, addition or improvement to the Premises,
Tenant shall give Landlord at least ten (10) business days' written notice of
the proposed commencement of such work (to afford Landlord an opportunity to
post appropriate notices of non-responsibility).  In the event that there shall
be recorded against the Premises or the Project or the property of which the
Premises is a part any claim or lien arising out of any such work performed,
materials furnished or obligations incurred by Tenant and such claim or lien
shall not be removed or discharged within ten (10) days of filing, Landlord may
notify Tenant that, unless Tenant causes the removal

                                      -11-
<PAGE>

thereof within three (3) business days, Landlord shall pay and discharge the
lien and charge Tenant the amounts so paid and discharged, in which event, if
Tenant fails to cause such removal within such 3-day period, Landlord shall have
the right but not the obligation to pay and discharge said lien without regard
to whether such lien shall be lawful or correct or to require that Tenant
deposit with Landlord in cash, lawful money of the United States, one hundred
fifty percent (150%) of the amount of such claim, which sum may be retained by
Landlord until such claim shall have been removed of record or until judgment
shall have been rendered on such claim and such judgment shall have become
final, at which time Landlord shall have the right to apply such deposit in
discharge of the judgment on said claim and any costs, including attorneys' fees
and costs incurred by Landlord, and shall remit the balance thereof to Tenant.

                                  ARTICLE 11
                                  ----------

                               PROJECT SERVICES
                               ----------------

   (a) Landlord agrees to furnish to the Premises, at a cost to be included in
Operating Costs, from 8:00 a.m. to 6:00 p.m. Mondays through Fridays and 9:00
a.m. to 1:00 p.m. on Saturdays, excepting local and national holidays, air
conditioning and heat all in such reasonable quantities as in the judgment of
Landlord is reasonably necessary for the comfortable occupancy of the Premises.
In addition, Landlord shall provide electric current for normal lighting and
normal office machines, elevator service and water on the same floor as the
Premises for lavatory and drinking purposes in such reasonable quantities as in
the judgment of Landlord is reasonably necessary for general office use.
Janitorial and maintenance services shall be furnished five (5) days per week,
excepting local and national holidays. Tenant shall comply with all rules and
regulations which Landlord may reasonably establish for the proper functioning
and protection of the common area air conditioning, heating, elevator,
electrical intrabuilding network cable and plumbing systems. Except as provided
in Section 11(g) below, Landlord shall not be liable for, and there shall be no
rent abatement as a result of, any stoppage, reduction or interruption of any
such services caused by governmental rules, regulations or ordinances, riot,
strike, labor disputes, breakdowns, accidents, necessary repairs or other cause.
Except as specifically provided in this Article 11, Tenant agrees to pay for all
utilities and other services utilized by Tenant and additional building services
furnished to Tenant not uniformly furnished to all tenants of the Project at the
rate generally charged by Landlord to tenants of the Project.

   (b) Tenant will not, without the prior written consent of Landlord, use any
apparatus or device in the Premises which will in any way increase the amount of
electricity or water usually furnished or supplied for use of the Premises as
general office space; nor connect any apparatus, machine or device with water
pipes or electric current (except through existing electrical outlets in the
Premises), for the purpose of using electric current or water.

   (c) If Tenant shall require electric current in excess of that which Landlord
is obligated to furnish under Article 11(a) above, Tenant shall first obtain the
written consent of Landlord to the use thereof and Landlord may cause an
electric current meter or submeter to be installed in the Premises to measure
the amount of such excess electric current consumed by Tenant in the Premises.
Landlord may refuse to provide such excess capacity if doing so requires changes
to the main feeders or capacity of the Project. The cost of any such meter and
of installation, maintenance and repair thereof shall be paid for by Tenant and
Tenant agrees to pay to Landlord, promptly upon demand therefor by Landlord, for
all such excess electric current consumed by any such use as shown by said meter
at the rates charged for such service by the city in which the Project is
located or the local public utility, as the case may be, furnishing the same,
plus any additional expense incurred by Landlord in keeping account of the
electric current so consumed.

   (d) If any lights, machines or equipment (including but not limited to
computers) are used by Tenant in the Premises which materially affect the
temperature otherwise maintained by the air conditioning system, or generate
substantially more heat in the Premises than would be generated by the building
standard lights and usual office equipment, Landlord shall have the right to
install any machinery and equipment which Landlord reasonably deems necessary to
restore temperature balance, including but not limited to modifications to the
standard air conditioning equipment, and the cost thereof, including the cost of
installation and any additional cost of operation and maintenance occasioned
thereby, shall be paid by Tenant to Landlord upon demand by Landlord. Landlord
shall not be liable under any circumstances for loss of or injury to property or
injury to, or interference with, Tenant's business (including, but not limited
to, loss

                                      -12-
<PAGE>

of profits), however occurring, through or in connection with or incidental to
failure to furnish any of the services or utilities specified in this Article
11.

   (e) If Tenant requires heating, ventilation and/or air conditioning during
times other than the times provided in Article 11(a) above, Tenant shall give
Landlord such advance notice as Landlord shall reasonably require and shall pay
Landlord's standard charge for such after-hours use.

   (f) Landlord may impose a reasonable charge for any utilities or services
(other than electric current and heating, ventilation and/or air conditioning
which shall be governed by Articles 11(c) and (e) above) utilized by Tenant in
excess of the amount or type that Landlord reasonably determines is typical for
general office use.

   (g) An "ABATEMENT EVENT" shall be defined as an event that prevents Tenant
from using the Premises or any portion thereof, as a result of any failure to
provide services or access to the Premises, where (i) Tenant does not actually
use the Premises or such portion thereof, and (ii) such event is not caused by
the negligence or willful misconduct of Tenant, its agents, employees or
contractors. Tenant shall give Landlord notice ("ABATEMENT NOTICE") of any such
Abatement Event, and if such Abatement Event continues beyond the "Eligibility
Period" (as that term is defined below), then the Basic Rental and Tenant's
Proportionate Share of Direct Costs and Tenant's obligation to pay for parking
shall be abated entirely or reduced, as the case may be, after expiration of the
Eligibility Period for such time that Tenant continues to be so prevented from
using, and does not use, the Premises or a portion thereof, in the proportion
that the rentable area of the portion of the Premises that Tenant is prevented
from using, and does not use, bears to the total rentable area of the Premises;
provided, however, in the event that Tenant is prevented from using, and does
not use, a portion of the Premises for a period of time in excess of the
Eligibility Period and the remaining portion of the Premises is not sufficient
to allow Tenant to effectively conduct its business therein, and if Tenant does
not conduct its business from such remaining portion, then for such time after
expiration of the Eligibility Period during which Tenant is so prevented from
effectively conducting its business therein, the Basic Rental and Tenant's
Proportionate Share of Direct Costs and Tenant's obligation to pay for parking
for the entire Premises shall be abated entirely for such time as Tenant
continues to be so prevented from using, and does not use, the Premises. If,
however, Tenant reoccupies any portion of the Premises during such period, the
Basic Rental and Tenant's Proportionate Share of Direct Costs allocable to such
reoccupied portion, based on the proportion that the rentable area of such
reoccupied portion of the Premises bears to the total rentable area of the
Premises, shall be payable by Tenant from the date Tenant reoccupies such
portion of the Premises. The term "ELIGIBILITY PERIOD" shall mean a period of
five (5) consecutive business days after Landlord's receipt of any Abatement
Notice(s). Such right to abate Basic Rental and Tenant's Proportionate Share of
Direct Costs shall be Tenant's sole and exclusive remedy at law or in equity for
an Abatement Event.

                                  ARTICLE 12
                                  ----------

                              RIGHTS OF LANDLORD
                              ------------------

     Landlord and its agents shall have the right to enter the Premises at all
reasonable times for the purpose of cleaning the Premises, examining or
inspecting the same, serving or posting and keeping posted thereon notices as
provided by law, or which Landlord deems necessary for the protection of
Landlord or the Property, showing the same to prospective tenants, lenders or
purchasers of the Project, in the case of an emergency, and for making such
alterations, repairs, improvements or additions to the Premises or to the
Project as Landlord may deem necessary or desirable.  If Tenant shall not be
personally present to open and permit an entry into the Premises at any time
when such an entry by Landlord is necessary or permitted hereunder, Landlord may
enter by means of a master key or may enter forcibly, only in the case of an
emergency, without liability to Tenant and without affecting this Lease.
Notwithstanding anything to the contrary contained in this Lease, Tenant may
designate certain areas of the Premises as "secured areas" should Tenant require
such areas for the purpose of securing certain valuable property or confidential
information.  In connection with the foregoing, Landlord shall not enter such
secured areas except during normal business hours and upon at least twenty-four
(24) hours notice to Tenant or in the event of an emergency.  Landlord shall not
provide any cleaning services to any area designated by Tenant as a secured
area.

                                      -13-
<PAGE>

                                  ARTICLE 13
                                  ----------

                INDEMNITY; EXEMPTION OF LANDLORD FROM LIABILITY
                -----------------------------------------------

   (a) Indemnity. Tenant shall indemnify, defend and hold Landlord harmless from
any and all claims arising from Tenant's use of the Premises or the Project or
from the conduct of its business or from any activity, work or thing which may
be permitted or suffered by Tenant in or about the Premises or the Project and
shall further indemnify, defend and hold Landlord harmless from and against any
and all claims arising from any breach or default in the performance of any
obligation on Tenant's part to be performed under this Lease or arising from any
negligence or willful misconduct of Tenant or any of its agents, contractors,
employees or invitees, patrons, customers or members in or about the Project and
from any and all costs, attorneys' fees and costs, expenses and liabilities
incurred in the defense of any claim or any action or proceeding brought
thereon, including negotiations in connection therewith. However,
notwithstanding the foregoing, Tenant shall not be required to indemnify and/or
hold Landlord harmless from any loss, cost, liability, damage or expense,
including, but not limited to, penalties, fines, attorneys' fees or costs
(collectively, "CLAIMS"), to any person, property or entity to the extent
resulting from the negligence or willful misconduct of Landlord or its agents,
contractors, or employees (except for damage to the Improvements and Tenant's
personal property, fixtures, furniture and equipment in the Premises in which
case Tenant shall be responsible to the extent Tenant is required to obtain the
requisite insurance coverage pursuant to this Lease). Landlord hereby
indemnifies Tenant and holds Tenant harmless from any Claims to the extent
resulting from the negligence or willful misconduct of Landlord or its agents,
contractors or employees; provided, however, that because Landlord maintains
insurance on the Project and Tenant compensates Landlord for such insurance as
part of Tenant's Proportionate Share of Direct Costs and because of the
existence of waivers of subrogation set forth in Article 14 of this Lease,
Landlord hereby indemnifies and holds Tenant harmless from any Claims to any
property outside of the Premises to the extent such Claim is covered by such
insurance, even if resulting from the negligent acts, omissions, or willful
misconduct of Tenant or those of its agents, contractors, or employees.
Similarly, since Tenant must carry insurance pursuant to Article 14 to cover its
personal property within the Premises and the Improvements, Tenant hereby
indemnifies and holds Landlord harmless from any Claim to any property within
the Premises, to the extent such Claim is covered by such insurance, even if
resulting from the negligent acts, omissions or willful misconduct of Landlord
or those of its agents, contractors, or employees. Tenant hereby assumes all
risk of damage to property or injury to persons in or about the Premises from
any cause, and Tenant hereby waives all claims in respect thereof against
Landlord, excepting where the damage is caused solely by the gross negligence or
willful misconduct of Landlord.

   (b) Exemption of Landlord from Liability. Landlord shall not be liable for
injury to Tenant's business, or loss of income therefrom, or, except in
connection with damage or injury resulting from the gross negligence or willful
misconduct of Landlord, or its authorized agents, for damage that may be
sustained by the person, goods, wares, merchandise or property of Tenant, its
employees, invitees, customers, agents, or contractors, or any other person in,
on or about the Premises directly or indirectly caused by or resulting from
fire, steam, electricity, gas, water, or rain which may leak or flow from or
into any part of the Premises, or from the breakage, leakage, obstruction or
other defects of the pipes, sprinklers, wires, appliances, plumbing, air
conditioning, light fixtures, or mechanical or electrical systems or from
intrabuilding network cable, whether such damage or injury results from
conditions arising upon the Premises or upon other portions of the Project or
from other sources or places and regardless of whether the cause of such damage
or injury or the means of repairing the same is inaccessible to Tenant. Landlord
shall not be liable to Tenant for any damages arising from any act or neglect of
any other tenant of the building.

                                  ARTICLE 14
                                  ----------

                                   INSURANCE
                                   ---------

   (a) Tenant's Insurance. Tenant, shall at all times during the Term of this
Lease, and at its own cost and expense, procure and continue in force the
following insurance coverage: (i) Commercial General Liability Insurance with a
combined single limit for bodily injury and property damages of not less than
Two Million Dollars ($2,000,000) per occurrence and Three

                                      -14-
<PAGE>

Million Dollars ($3,000,000) in the annual aggregate, including products
liability coverage if applicable, covering the insuring provisions of this Lease
and to the extent the same are insurable claims the performance of Tenant of the
indemnity and exemption of Landlord from liability agreements set forth in
Article 13 hereof; (ii) a policy of standard fire, extended coverage and special
extended coverage insurance (all risks), including a vandalism and malicious
mischief endorsement, sprinkler leakage coverage and earthquake sprinkler
leakage where the limit of liability is in an amount equal to the full
replacement value new without deduction for depreciation of all (A) Tenant
Improvements, Alterations, fixtures and other improvements in the Premises and
(B) trade fixtures, furniture, equipment and other personal property installed
by or at the expense of Tenant; (iii) Worker's Compensation coverage as required
by law; and (iv) business interruption, loss of income and extra expense
insurance covering the risks described in Section 14(a)(ii) above. Tenant shall
carry and maintain during the entire Lease Term (including any option periods,
if applicable), at Tenant's sole cost and expense, increased amounts of the
insurance required to be carried by Tenant pursuant to this Article 14 and such
other reasonable types of insurance coverage and in such reasonable amounts
covering the Premises and Tenant's operations therein, as may be reasonably
required by Landlord.

   (b) Form of Policies. The aforementioned minimum limits of policies and
Tenant's procurement and maintenance thereof shall in no event limit the
liability of Tenant hereunder. The Commercial General Liability Insurance policy
shall name Landlord, Landlord's property manager, Landlord's lender(s) and such
other persons or firms as Landlord specifies from time to time, as additional
insureds with an appropriate endorsement to the policy(s). All such insurance
policies carried by Tenant shall be with companies having a rating of not less
than A-VIII in Best's Insurance Guide. Tenant shall furnish to Landlord, from
the insurance companies, or cause the insurance companies to furnish,
certificates of coverage. No such policy shall be cancelable or subject to
reduction of coverage below the limits described in Section 14(a) above or other
modification or cancellation except after thirty (30) days prior written notice
to Landlord by the insurer. All such policies shall be endorsed to agree that
Tenant's policy is primary as to claims within the Premises and that any
insurance carried by Landlord is excess and not contributing with any Tenant
insurance requirement hereunder. Tenant shall, at least twenty (20) days prior
to the expiration of such policies, furnish Landlord with renewal certificates
or binders. Tenant agrees that if Tenant does not take out and maintain such
insurance or furnish Landlord with renewal certificates or binders, Landlord may
(but shall not be required to) upon prior notice to Tenant and the expiration of
a five (5) day cure period procure said insurance on Tenant's behalf and charge
Tenant the cost thereof, which amount shall be payable by Tenant upon demand
with interest (at the rate set forth in Section 20(e) below) from the date such
sums are extended. Tenant shall have the right to provide such insurance
coverage pursuant to blanket policies obtained by Tenant, provided such blanket
policies expressly afford coverage to the Premises and to Tenant as required by
this Lease.

   (c) Landlord's Insurance. Landlord shall, as a cost to be included in
Operating Costs, procure and maintain at all times during the Term of this
Lease, a policy or policies of insurance covering loss or damage to the Project
in the amount of the full replacement costs without deduction for depreciation
thereof (exclusive of Tenant's trade fixtures, inventory, personal property and
equipment), providing protection against all perils included within the
classification of fire and extended coverage, vandalism coverage and malicious
mischief, sprinkler leakage, water damage, and special extended coverage on
building. Additionally, Landlord may (but shall not be required to) carry: (i)
Bodily Injury and Property Damage Liability Insurance and/or Excess Liability
Coverage Insurance; and (ii) Earthquake and/or Flood Damage Insurance; and (iii)
Rental Income Insurance at its election or if required by its lender from time
to time during the Term hereof, in such amounts and with such limits as Landlord
or its lender may deem appropriate. The costs of such insurance shall be
included in Operating Costs.

   (d) Waiver of Subrogation. Landlord and Tenant each agree to have their
respective insurers issuing the insurance described in Sections 14(a)(ii),
14(a)(iv) and the first sentence of Section 14(c) waive any rights of
subrogation that such companies may have against the other party. Tenant hereby
waives any right that Tenant may have against Landlord and Landlord hereby
waives any right that Landlord may have against Tenant as a result of any loss
or damage to the extent such loss or damage is insurable under such policies.

   (e) Compliance with Law. Tenant agrees that it will not, at any time, during
the Term of this Lease, carry any stock of goods or do anything in or about the
Premises that will in

                                      -15-
<PAGE>

any way tend to increase the insurance rates upon the Project. Tenant agrees to
pay Landlord forthwith upon demand the amount of any increase in premiums for
insurance against loss by fire that may be charged during the Term of this Lease
on the amount of insurance to be carried by Landlord on the Project resulting
from the foregoing, or from Tenant doing any act in or about said Premises that
does so increase the insurance rates, whether or not Landlord shall have
consented to such act on the part of Tenant. If Tenant installs upon the
Premises any electrical equipment which constitutes an overload of electrical
lines of the Premises, Tenant shall at its own cost and expense in accordance
with all other Lease provisions, and subject to the provisions of Article 9, 10
and 11, hereof, make whatever changes are necessary to comply with requirements
of the insurance underwriters and any governmental authority having jurisdiction
thereover, but nothing herein contained shall be deemed to constitute Landlord's
consent to such overloading. Tenant shall, at its own expense, comply with all
requirements of the insurance authority having jurisdiction over the Project
necessary for the maintenance of reasonable fire and extended coverage insurance
for the Premises, including without limitation thereto, the installation of fire
extinguishers or an automatic dry chemical extinguishing system.

                                  ARTICLE 15
                                  ----------

                           ASSIGNMENT AND SUBLETTING
                           -------------------------

     Tenant shall have no power to, either voluntarily, involuntarily, by
operation of law or otherwise, sell, assign, transfer or hypothecate this Lease,
or sublet the Premises or any part thereof, or permit the Premises or any part
thereof to be used or occupied by anyone other than Tenant or Tenant's employees
without the prior written consent of Landlord which shall not be unreasonably
withheld.  Tenant may transfer its interest pursuant to this Lease only upon the
following express conditions, which conditions are agreed by Landlord and Tenant
to be reasonable:

   (a)  That the proposed transferee shall be subject to the prior written
consent of Landlord, which consent will not be unreasonably withheld but,
without limiting the generality of the foregoing, it shall be reasonable for
Landlord to deny such consent if:

        (i) The use to be made of the Premises by the proposed transferee is (a)
not generally consistent with the character and nature of all other tenancies in
the Project, or (b) a use which conflicts with any so-called "exclusive" then in
favor of another tenant of the Project or any other buildings which are in the
same complex as the Project, or (c) a use which would be prohibited by any other
portion of this Lease (including but not limited to any Rules and Regulations
then in effect);

        (ii) The financial responsibility of the proposed transferee is not
reasonably satisfactory to Landlord;

        (iii) The proposed transferee is either a governmental agency or
instrumentality thereof; or

        (iv) Either the proposed transferee or any person or entity which
directly or indirectly controls, is controlled by or is under common control
with the proposed transferee is negotiating with Landlord to lease space in the
Project.

   (b) Whether or not Landlord consents to any such transfer, Tenant shall pay
to Landlord Landlord's then standard processing fee and reasonable attorneys'
fees and costs incurred in connection with the proposed transfer up to the
aggregate sum of $1,500.00;

   (c) That the proposed transferee shall execute an agreement pursuant to which
it shall agree to perform faithfully and be bound by all of the terms,
covenants, conditions, provisions and agreements of this Lease applicable to
that portion of the Premises so transferred; and

   (d) That an executed duplicate original of said assignment and assumption
agreement or other transfer on a form reasonably approved by Landlord, shall be
delivered to Landlord within five (5) days after the execution thereof, and that
such transfer shall not be binding upon Landlord until the delivery thereof to
Landlord and the execution and delivery of Landlord's consent thereto. It shall
be a condition to Landlord's consent to any subleasing, assignment or other
transfer of part or all of Tenant's interest in the Premises (hereinafter
referred to as a

                                      -16-
<PAGE>

"TRANSFER") that (i) upon Landlord's consent to any Transfer, Tenant shall pay
and continue to pay fifty percent (50%) of any "Transfer Premium" (defined
below), received by Tenant from the transferee; (ii) any sublessee of part or
all of Tenant's interest in the Premises shall agree that in the event Landlord
gives such sublessee notice that Tenant is in default under this Lease, such
sublessee shall thereafter make all sublease or other payments directly to
Landlord, which will be received by Landlord without any liability whether to
honor the sublease or otherwise (except to credit such payments against sums due
under this Lease), and any sublessee shall agree to attorn to Landlord or its
successors and assigns at their request should this Lease be terminated for any
reason, except that in no event shall Landlord or its successors or assigns be
obligated to accept such attornment; (iii) any such Transfer and consent shall
be effected on forms supplied by Landlord and/or its legal counsel; (iv)
Landlord may require that Tenant not then be in default hereunder in any
respect; and (v) Tenant or the proposed subtenant or assignee (collectively,
"TRANSFEREE") shall agree to pay Landlord, upon demand, as additional rent, a
sum equal to the additional costs, if any, incurred by Landlord for maintenance
and repair as a result of any change in the nature of occupancy caused by such
subletting or assignment. "TRANSFER PREMIUM" shall mean all rent, additional
rent or other consideration payable by a Transferee in connection with a
Transfer in excess of the rent and Additional Rent payable by Tenant under this
Lease during the term of the Transfer and if such Transfer is less than all of
the Premises, the Transfer Premium shall be calculated on a rentable square foot
basis. In any event, the Transfer Premium shall be calculated after deducting
the reasonable expenses incurred by Tenant for (1) any changes, alterations, and
improvements to the Premises paid for by Tenant in connection with the Transfer,
(2) any other out-of-pocket monetary concessions provided by Tenant to the
Transferee, and (3) any brokerage commissions paid for by Tenant in connection
with the Transfer. "Transfer Premium" shall also include, but not be limited to,
key money, bonus money or other cash consideration paid by a transferee to
Tenant in connection with such Transfer, and any payment in excess of fair
market value for services rendered by Tenant to the Transferee and any payment
in excess of fair market value for assets, fixtures, inventory, equipment, or
furniture transferred by Tenant to the Transferee in connection with such
Transfer. Any sale, assignment, hypothecation, transfer or subletting of this
Lease which is not in compliance with the provisions of this Article 15 shall be
void and shall, at the option of Landlord, terminate this Lease. In no event
shall the consent by Landlord to an assignment or subletting be construed as
relieving Tenant, any assignee, or sublessee from obtaining the express written
consent of Landlord to any further assignment or subletting, or as releasing
Tenant from any liability or obligation hereunder whether or not then accrued
and Tenant shall continue to be fully liable therefor. No collection or
acceptance of rent by Landlord from any person other than Tenant shall be deemed
a waiver of any provision of this Article 15 or the acceptance of any assignee
or subtenant hereunder, or a release of Tenant (or of any successor of Tenant or
any subtenant). Notwithstanding anything to the contrary in this Lease, if
Tenant or any proposed Transferee claims that Landlord has unreasonably withheld
or delayed its consent under this Article 15 or otherwise has breached or acted
unreasonably under this Article 15, their sole remedies shall be a declaratory
judgment, an injunction for the relief sought and/or monetary damages, and
Tenant hereby waives any right at law or equity to terminate this Lease.

     Notwithstanding anything to the contrary contained in this Article 15,
Landlord shall have the option, by giving written notice to Tenant within thirty
(30) days after Landlord's receipt of a request for consent to a proposed
Transfer, to terminate this Lease as to the portion of the Premises that is the
subject of the Transfer.  If this Lease is so terminated with respect to less
than the entire Premises, the Basic Rental and Tenant's Proportionate Share
shall be prorated based on the number of rentable square feet retained by Tenant
as compared to the total number of rentable square feet contained in the
original Premises, and this Lease as so amended shall continue thereafter in
full force and effect, and upon the request of either party, the parties shall
execute written confirmation of the same.

                                  ARTICLE 16
                                  ----------

                             DAMAGE OR DESTRUCTION
                             ---------------------

     Within sixty (60) days after the date the Landlord learns of the necessity
for repairs as a result of damage, Landlord shall notify Tenant ("DAMAGE REPAIR
ESTIMATE") of Landlord's estimated assessment of the period in which the repairs
will be completed.  If the Project is damaged by fire or other insured casualty
and the insurance proceeds have been made available therefor by the holder or
holders of any mortgages or deeds of trust covering the Premises or the

                                      -17-
<PAGE>

Project, the damage shall be repaired by Landlord to the extent such insurance
proceeds are available therefor and provided the Damage Repair Estimate
indicates that repairs can be completed within one hundred eighty (180) days
after the necessity for repairs as a result of such damage becomes known to
Landlord without the payment of overtime or other premiums, and until such
repairs are completed rent shall be abated in proportion to the part of the
Premises which is unusable by Tenant in the conduct of its business (but there
shall be no abatement of rent by reason of any portion of the Premises being
unusable for a period equal to one (1) day or less). However, if the damage is
due to the fault or neglect of Tenant, its employees, agents, contractors,
guests, invitees and the like, there shall be no abatement of rent, unless and
to the extent Landlord receives rental income insurance proceeds. Upon the
occurrence of any damage to the Premises, Tenant shall assign to Landlord (or to
any party designated by Landlord) all insurance proceeds payable to Tenant under
Section 14(a)(ii)(A) above; provided, however, that if the cost of repair of
improvements within the Premises by Landlord exceeds the amount of insurance
proceeds received by Landlord from Tenant's insurance carrier, as so assigned by
Tenant, such excess costs shall be paid by Tenant to Landlord prior to
Landlord's repair of such damage. If, however, the Damage Repair Estimate
indicates that repairs cannot be completed within one hundred eighty (180) days
after the necessity for repairs as a result of such damage becomes known to
Landlord without the payment of overtime or other premiums, Landlord may, at its
option, either (i) make them in a reasonable time and in such event this Lease
shall continue in effect and the rent shall be abated, if at all, in the manner
provided in this Article 16, or (ii) elect not to effect such repairs and
instead terminate this Lease, by notifying Tenant in writing of such termination
within sixty (60) days after Landlord learns of the necessity for repairs as a
result of damage, such notice to include a termination date giving Tenant sixty
(60) days to vacate the Premises. In addition, Landlord may elect to terminate
this Lease if the Project shall be damaged by fire or other casualty or cause,
whether or not the Premises are affected, and the damage is not fully covered,
except for deductible amounts, by Landlord's insurance policies. However, if
Landlord does not elect to terminate this Lease pursuant to Landlord's
termination right as provided above, and the Damage Repair Estimate indicates
that repairs cannot be completed within one hundred eighty (180) days after
being commenced, Tenant may elect, not later than thirty (30) days after
Tenant's receipt of the Damage Repair Estimate to terminate this Lease by
written notice to Landlord effective as of the date specified in Tenant's
notice. Finally, if the Premises or the Project is damaged to any substantial
extent during the last twelve (12) months of the Term, then notwithstanding
anything contained in this Article 16 to the contrary, Landlord shall have the
option to terminate this Lease by giving written notice to Tenant of the
exercise of such option within sixty (60) days after Landlord learns of the
necessity for repairs as the result of such damage. In the event that the
Premises or the Project is destroyed or damaged to any substantial extent during
the last twelve (12) months of the Lease Term and if such damage shall take
longer than sixty (60) days to repair and if such damage is not the result of
the negligence or willful misconduct of Tenant or Tenant's employees, licensees,
invitees, or agents, then notwithstanding anything contained in this Article 16
to the contrary, Tenant shall have the option to terminate this Lease by written
notice to Landlord of the exercise of such option within sixty (60) days after
Tenant learns of the necessity for repairs as a result of such damage. A total
destruction of the Project shall automatically terminate this Lease. Except as
provided in this Article 16, there shall be no abatement of rent and no
liability of Landlord by reason of any injury to or interference with Tenant's
business or property arising from such damage or destruction or the making of
any repairs, alterations or improvements in or to any portion of the Project or
the Premises or in or to fixtures, appurtenances and equipment therein. Tenant
understands that Landlord will not carry insurance of any kind on Tenant's
furniture, furnishings, trade fixtures or equipment, and that Landlord shall not
be obligated to repair any damage thereto or replace the same. Except for
proceeds relating solely to Tenant's furniture, furnishings, trade fixtures and
equipment, Tenant acknowledges that Tenant shall have no right to any proceeds
of insurance relating to property damage. With respect to any damage which
Landlord is obligated to repair or elects to repair, Tenant, as a material
inducement to Landlord entering into this Lease, irrevocably waives and releases
its rights under the provisions of Sections 1932 and 1933 of the California
Civil Code.

                                  ARTICLE 17
                                  ----------

                                 SUBORDINATION
                                 -------------

     This Lease is subject and subordinate to all ground or underlying leases,
mortgages and deeds of trust which affect the property or the Project, including
all renewals, modifications,

                                      -18-
<PAGE>

consolidations, replacements and extensions thereof; provided, however, if the
lessor under any such lease or the holder or holders of any such mortgage or
deed of trust shall advise Landlord that they desire or require this Lease to be
prior and superior thereto, upon written request of Landlord to Tenant, Tenant
agrees to promptly execute, acknowledge and deliver any and all documents or
instruments which Landlord or such lessor, holder or holders deem necessary or
desirable for purposes thereof. Landlord shall have the right to cause this
Lease to be and become and remain subject and subordinate to any and all ground
or underlying leases, mortgages or deeds of trust which may hereafter be
executed covering the Premises, the Project or the property or any renewals,
modifications, consolidations, replacements or extensions thereof, for the full
amount of all advances made or to be made thereunder and without regard to the
time or character of such advances, together with interest thereon and subject
to all the terms and provisions thereof; provided, however, that Landlord
obtains from the lender or other party in question a written undertaking in
favor of Tenant to the effect that such lender or other party will not disturb
Tenant's right of possession under this Lease if Tenant is not then or
thereafter in breach of any covenant or provision of this Lease. Tenant agrees,
within ten (10) days after Landlord's written request therefor, to execute,
acknowledge and deliver upon request any and all documents or instruments
requested by Landlord or necessary or proper to assure the subordination of this
Lease to any such mortgages, deed of trust, or leasehold estates. Tenant agrees
that in the event any proceedings are brought for the foreclosure of any
mortgage or deed of trust or any deed in lieu thereof, to attorn to the
purchaser or any successors thereto upon any such foreclosure sale or deed in
lieu thereof as so requested to do so by such purchaser and to recognize such
purchaser as the lessor under this Lease; Tenant shall, within ten (10) days
after request execute such further instruments or assurances as such purchaser
may reasonably deem necessary to evidence or confirm such attornment. Tenant
agrees to provide copies of any notices of Landlord's default under this Lease
to any mortgagee or deed of trust beneficiary whose address has been provided to
Tenant and Tenant shall provide such mortgagee or deed of trust beneficiary a
commercially reasonable time after receipt of such notice within which to cure
any such default. Tenant waives the provisions of any current or future statute,
rule or law which may give or purport to give Tenant any right or election to
terminate or otherwise adversely affect this Lease and the obligations of the
Tenant hereunder in the event of any foreclosure proceeding or sale.

                                  ARTICLE 18
                                  ----------

                                EMINENT DOMAIN
                                --------------

     If the whole of the Premises or the Project or so much thereof as to render
the balance unusable by Tenant shall be taken under power of eminent domain, or
is sold, transferred or conveyed in lieu thereof, this Lease shall automatically
terminate as of the date of such condemnation, or as of the date possession is
taken by the condemning authority, at Landlord's option.  No award for any
partial or entire taking shall be apportioned, and Tenant hereby assigns to
Landlord any award which may be made in such taking or condemnation, together
with any and all rights of Tenant now or hereafter arising in or to the same or
any part thereof; provided, however, that nothing contained herein shall be
deemed to give Landlord any interest in or to require Tenant to assign to
Landlord any award made to Tenant for relocation expenses or for the taking of
personal property and trade fixtures belonging to Tenant and removable by Tenant
at the expiration of the Term hereof as provided hereunder or for the
interruption of, or damage to, Tenant's business.  In the event of a partial
taking described in this Article 18, or a sale, transfer or conveyance in lieu
thereof, which does not result in a termination of this Lease, the rent shall be
apportioned according to the ratio that the part of the Premises remaining
useable by Tenant bears to the total area of the Premises.  Tenant hereby waives
any and all rights it might otherwise have pursuant to Section 1265.130 of the
California Code of Civil Procedure.

                                  ARTICLE 19
                                  ----------

                                    DEFAULT
                                    -------

   (a) Tenant's Default. Each of the following acts or omissions of Tenant or of
any guarantor of Tenant's performance hereunder, or occurrences, shall
constitute an "EVENT OF DEFAULT":

        (i) Failure or refusal to pay Basic Rental, Additional Rent or any other
amount to be paid by Tenant to Landlord hereunder within five (5) calendar days
after notice that

                                      -19-
<PAGE>

the same is due or payable hereunder; said five (5) day period shall be in lieu
of, and not in addition to, the notice requirements of Section 1161 of the
California Code of Civil Procedure or any similar or successor law;

        (ii) Except as set forth in items (i) above and (iii) below, failure to
perform or observe any other covenant or condition of this Lease to be performed
or observed within thirty (30) days following written notice to Tenant of such
failure; however, if the nature of such default is such that the same cannot be
reasonably cured within a thirty (30) day period, Tenant shall not be deemed to
be in default if Tenant diligently commences such cure within such period and
thereafter diligently proceeds to rectify and cure said default. Such thirty
(30) day notice shall be in lieu of, and not in addition to, any required under
Section 1161 of the California Code of Civil Procedure or any similar or
successor law; or

        (iii) Tenant's failure to observe or perform according to the provisions
of Articles 7, 17 or 25 within five (5) business days after notice from
Landlord.

   (b) Landlord's Default. Notwithstanding anything to the contrary set forth in
this Lease, Landlord shall be in default in the performance of any obligation
required to be performed by Landlord pursuant to this Lease if Landlord fails to
perform such obligation within thirty (30) days after the receipt of notice from
Tenant specifying in detail Landlord's failure to perform; provided, however, if
the nature of Landlord's obligation is such that more than thirty (30) days are
required for its performance, then Landlord shall not be in default under this
Lease if it shall commence such performance within such thirty (30) day period
and thereafter diligently pursue the same to completion. Upon any such default
by Landlord under this Lease, Tenant may, except as otherwise specifically
provided in this Lease to the contrary, exercise any of its rights provided at
law or in equity.

                                  ARTICLE 20
                                  ----------

                                   REMEDIES
                                   --------

   (a) Upon the occurrence of an Event of Default under this Lease as provided
in Article 19 hereof, Landlord may exercise all of its remedies as may be
permitted by law, including but not limited to the remedy provided by Section
1951.4 of the California Civil Code, and including without limitation,
terminating this Lease, reentering the Premises and removing all persons and
property therefrom, which property may be stored by Landlord at a warehouse or
elsewhere at the risk, expense and for the account of Tenant. If Landlord elects
to terminate this Lease, Landlord shall be entitled to recover from Tenant the
aggregate of all amounts permitted by law, including but not limited to (i) the
worth at the time of award of the amount of any unpaid rent which had been
earned at the time of such termination; plus (ii) the worth at the time of award
of the amount by which the unpaid rent which would have been earned after
termination until the time of award exceeds the amount of such rental loss that
Tenant proves could have been reasonably avoided; plus (iii) the worth at the
time of award of the amount by which the unpaid rent for the balance of the
Lease Term after the time of award exceeds the amount of such rental loss that
Tenant proves could have been reasonably avoided; plus (iv) any other amount
necessary to compensate Landlord for all the detriment proximately caused by
Tenant's failure to perform its obligations under this Lease or which in the
ordinary course of things would be likely to result therefrom; and (v) at
Landlord's election, such other amounts in addition to or in lieu of the
foregoing as may be permitted from time to time by applicable law. The term
"rent" as used in this Article 20(a) shall be deemed to be and to mean all sums
of every nature required to be paid by Tenant pursuant to the terms of this
Lease, whether to Landlord or to others. As used in items (i) and (ii), above,
the "worth at the time of award" shall be computed by allowing interest at the
rate set forth in item (e), below, but in no case greater than the maximum
amount of such interest permitted by law. As used in item (iii), above, the
"worth at the time of award" shall be computed by discounting such amount at the
discount rate of the Federal Reserve Bank of San Francisco at the time of award
plus one percent (1%).

   (b) Nothing in this Article 20 shall be deemed to affect Landlord's right to
indemnification for liability or liabilities arising prior to the termination of
this Lease for personal injuries or property damage under the indemnification
clause or clauses contained in this Lease.

                                      -20-
<PAGE>

   (c) Notwithstanding anything to the contrary set forth herein, Landlord's re-
entry to perform acts of maintenance or preservation of or in connection with
efforts to relet the Premises or any portion thereof, or the appointment of a
receiver upon Landlord's initiative to protect Landlord's interest under this
Lease shall not terminate Tenant's right to possession of the Premises or any
portion thereof and, until Landlord does elect to terminate this Lease, this
Lease shall continue in full force and effect and Landlord may enforce all of
Landlord's rights and remedies hereunder including, without limitation, the
remedy described in California Civil Code Section 1951.4 (lessor may continue
lease in effect after lessee's breach and abandonment and recover rent as it
becomes due, if lessee has the right to sublet or assign, subject only to
reasonable limitations). Accordingly, if Landlord does not elect to terminate
this Lease on account of any default by Tenant, Landlord may, from time to time,
without terminating this Lease, enforce all of its rights and remedies under
this Lease, including the right to recover all rent as it becomes due.

   (d) All rights, powers and remedies of Landlord hereunder and under any other
agreement now or hereafter in force between Landlord and Tenant shall be
cumulative and not alternative and shall be in addition to all rights, powers
and remedies given to Landlord by law, and the exercise of one or more rights or
remedies shall not impair Landlord's right to exercise any other right or
remedy.

   (e) Any amount due from Tenant to Landlord hereunder which is not paid when
due shall bear interest at the lower of twelve percent (12%) per annum or the
maximum lawful rate of interest from the due date until paid, unless otherwise
specifically provided herein, but the payment of such interest shall not excuse
or cure any default by Tenant under this Lease. In addition to such interest:
(i) if Basic Rental is not paid within ten (10) days after the same is due, a
late charge equal to five percent (5%) of the amount overdue shall be assessed
and shall accrue for each calendar month or part thereof until such rental,
including the late charge, is paid in full, which late charge Tenant hereby
agrees is a reasonable estimate of the damages Landlord shall suffer as a result
of Tenant's late payment and (ii) an additional charge of $25 shall be assessed
for any check given to Landlord by or on behalf of Tenant which is not honored
by the drawee thereof; which damages include Landlord's additional
administrative and other costs associated with such late payment and unsatisfied
checks and the parties agree that it would be impracticable or extremely
difficult to fix Landlord's actual damage in such event. Such charges for
interest and late payments and unsatisfied checks are separate and cumulative
and are in addition to and shall not diminish or represent a substitute for any
or all of Landlord's rights or remedies under any other provision of this Lease.

                                  ARTICLE 21
                                  ----------

                        TRANSFER OF LANDLORD'S INTEREST
                        -------------------------------

     In the event of any transfer or termination of Landlord's interest in the
Premises or the Project by sale, assignment, transfer, foreclosure, deed-in-lieu
of foreclosure or otherwise whether voluntary or involuntary, Landlord shall be
automatically relieved of any and all obligations and liabilities on the part of
Landlord from and after the date of such transfer or termination, including
furthermore without limitation, the obligation of Landlord under Article 4 and
California Civil Code 1950.7 above to return the security deposit, provided said
security deposit is transferred to said transferee and said transferee assumes
the obligations of Landlord under this Lease.  Tenant agrees to attorn to the
transferee upon any such transfer and to recognize such transferee as the lessor
under this Lease and Tenant shall, within five (5) days after request, execute
such further instruments or assurances as such transferee may reasonably deem
necessary to evidence or confirm such attornment.

                                  ARTICLE 22
                                  ----------

                                    BROKER
                                    ------

     Landlord and Tenant hereby warrant to each other that they have had no
dealings with any real estate broker or agent in connection with the negotiation
of this Lease, excepting only the real estate brokers or agents specified in
Article 1.H. of the Basic Lease Provisions (the "BROKER"), and that they know of
no other real estate broker or agent who is entitled to a commission in
connection with this Lease.  Pursuant to Landlord's separate agreement with the
Broker, Landlord shall pay the brokerage commissions owing to the Broker in
connection with

                                      -21-
<PAGE>

the transaction contemplated by this Lease. Each party agrees to indemnify and
defend the other party against and hold the other party harmless from any and
all claims, demands, losses, liabilities, lawsuits, judgments, and costs and
expenses (including without limitation reasonable attorneys' fees) with respect
to any leasing commission or equivalent compensation alleged to be owing on
account of the indemnifying party's dealings with any real estate broker or
agent other than the Broker. The terms of this Article 22 shall survive the
expiration of earlier termination of the Lease Term.

                                  ARTICLE 23
                                  ----------

                                    PARKING
                                    -------

     Tenant shall be entitled to rent from Landlord, commencing on the date of
expiration of the Abatement Period, the number of unreserved parking passes set
forth in Section 1(I) of the Basic Lease Provisions, which parking passes shall
pertain to the parking facility located adjacent to the Project.  Tenant shall
pay to Landlord for automobile parking passes the prevailing rate charged from
time to time at the location of such parking passes which rates are currently
$65.00 per parking pass per month (plus any applicable parking tax).  In
addition, Tenant shall be responsible for the full amount of any taxes imposed
by any governmental authority in connection with the renting of such parking
passes by Tenant or the use of the parking facility by Tenant.  Tenant's
continued right to use the parking passes is conditioned upon Tenant abiding by
all rules and regulations which are prescribed from time to time for the orderly
operation and use of the parking facility where the parking passes are located,
including any sticker or other identification system established by Landlord,
Tenant's cooperation in seeing that Tenant's employees and visitors also comply
with such rules and regulations, and Tenant not being in default under this
Lease.  Landlord specifically reserves the right to change the size,
configuration, design, layout and all other aspects of the Project parking
facility at any time and Tenant acknowledges and agrees that Landlord may,
without incurring any liability to Tenant and without any abatement of rent
under this Lease, from time to time, close-off or restrict access to the Project
parking facility for purposes of permitting or facilitating any such
construction, alteration or improvements.  Landlord may relocate any reserved
parking spaces rented by Tenant to another location in the Parking project
facility.  Landlord may delegate its responsibilities hereunder to a parking
operator or a lessee of the parking facility in which case such parking operator
or lessee shall have all the rights of control attributed hereby to the
Landlord.  The parking passes rented by Tenant pursuant to this Article 23 are
provided to Tenant solely for use by Tenant's own personnel and such passes may
not be transferred, assigned, subleased or otherwise alienated by Tenant without
Landlord's prior approval.  Tenant may validate visitor parking by such method
or methods as the Landlord may establish, at the validation rate from time to
time generally applicable to visitor parking.

                                  ARTICLE 24
                                  ----------

                                    WAIVER
                                    ------

     No waiver by Landlord or Tenant of any provision of this Lease shall be
deemed to be a waiver of any other provision hereof or of any subsequent breach
of the same or any other provision.  No provision of this Lease may be waived by
Landlord or Tenant, except by an instrument in writing executed by Landlord and
Tenant.  Landlord's consent to or approval of any act by Tenant requiring
Landlord's consent or approval shall not be deemed to render unnecessary the
obtaining of Landlord's consent to or approval of any subsequent act of Tenant,
whether or not similar to the act so consented to or approved.  No act or thing
done by Landlord or Landlord's agents during the Term of this Lease shall be
deemed an acceptance of a surrender of the Premises, and no agreement to accept
such surrender shall be valid unless in writing and signed by Landlord.  The
subsequent acceptance of rent hereunder by Landlord shall not be deemed to be a
waiver of any preceding breach by Tenant of any term, covenant or condition of
this Lease, other than the failure of Tenant to pay the particular rent so
accepted, regardless of Landlord's knowledge of such preceding breach at the
time of acceptance of such rent.  Any payment by Tenant or receipt by Landlord
of an amount less than the total amount then due hereunder shall be deemed to be
in partial payment only thereof and not a waiver of the balance due or an accord
and satisfaction, notwithstanding any statement or endorsement to the contrary
on any check or any other instrument delivered concurrently therewith or in
reference thereto.  Accordingly, Landlord may accept any such amount and
negotiate any such check without

                                      -22-
<PAGE>

prejudice to Landlord's right to recover all balances due and owing and to
pursue its other rights against Tenant under this Lease, regardless of whether
Landlord makes any notation on such instrument of payment or otherwise notifies
Tenant that such acceptance or negotiation is without prejudice to Landlord's
rights.

                                  ARTICLE 25
                                  ----------

                             ESTOPPEL CERTIFICATE
                             --------------------

     Tenant shall, at any time and from time to time, upon not less than ten
(10) business days' prior written notice from Landlord, execute, acknowledge and
deliver to Landlord a statement in writing certifying the following information,
(but not limited to the following information in the event further information
is requested by Landlord): (i) that this Lease is unmodified and in full force
and effect (or, if modified, stating the nature of such modification and
certifying that this Lease, as modified, is in full force and effect); (ii) the
dates to which the rental and other charges are paid in advance, if any; (iii)
the amount of Tenant's security deposit, if any; and (iv) acknowledging that
there are not, to Tenant's knowledge, any uncured defaults on the part of
Landlord hereunder, and no events or conditions then in existence which, with
the passage of time or notice or both, would constitute a default on the part of
Landlord hereunder, or specifying such defaults, events or conditions, if any
are claimed.  It is expressly understood and agreed that any such statement may
be relied upon by any prospective purchaser or encumbrancer of all or any
portion of the Real Property.  Tenant's failure to deliver such statement within
such time shall constitute an admission by Tenant that all statements contained
therein are true and correct.  Tenant agrees to execute all documents required
in accordance with this Article 25 within ten (10) business days after delivery
of said documents.  Tenant hereby irrevocably appoints Landlord as Tenant's
attorney-in-fact and in Tenant's name, place and stead to execute any and all
documents described in this Article 25 if Tenant fails to do so within the
specified time period.

                                  ARTICLE 26
                                  ----------

                             LIABILITY OF LANDLORD
                             ---------------------

     Notwithstanding anything in this Lease to the contrary, any remedy of
Tenant for the collection of a judgment (or other judicial process) requiring
the payment of money by Landlord in the event of any default by Landlord
hereunder or any claim, cause of action or obligation, contractual, statutory or
otherwise by Tenant against Landlord  concerning, arising out of or relating to
any matter relating to this Lease and all of the covenants and conditions or any
obligations, contractual, statutory, or otherwise set forth herein, shall be
limited solely and exclusively to an amount which is equal to the sum of (a) the
proceeds of the Letter of Credit (or the actual Letter of Credit to the extent
the Letter of Credit has not been drawn upon) plus (b) the lesser of (i) the
interest of Landlord in and to the Project, and (ii) the interest Landlord would
have in the Project if the Project were encumbered by third party debt in an
amount equal to eighty percent (80%) of the then current value of the Project
(as such value is reasonably determined by Landlord).  No other property or
assets of Landlord, or any member, officer, director, shareholder, partner,
trustee, agent, servant or employee of Landlord (the "REPRESENTATIVE") shall be
subject to levy, execution or other enforcement procedure for the satisfaction
of Tenant's remedies under or with respect to this Lease, Landlord's obligations
to Tenant, whether contractual, statutory or otherwise, the relationship of
Landlord and Tenant hereunder, or Tenant's use or occupancy of the Premises.
Tenant further understands that any liability, duty or obligation of Landlord to
Tenant, shall automatically cease and terminate as of the date that Landlord or
any of Landlord's Representatives no longer have any right, title or interest in
or to the Project provided that any successor or transferee of Landlord shall
assume the obligations of Landlord under this Lease.  Except as specifically
provided in this Lease, Landlord shall not be liable under any circumstances for
injury or damage to, or interference with, Tenant's business, including but not
limited to, loss of profits, loss of rents or other revenues, loss of business
opportunity, loss of goodwill or loss of use, in each case, however occurring.

                                      -23-
<PAGE>

                                  ARTICLE 27
                                  ----------

                             INABILITY TO PERFORM
                             --------------------

     This Lease and the obligations of both parties hereunder shall not be
affected or impaired because such party is unable to fulfill any of its
obligations hereunder or is delayed in doing so, if such inability or delay is
caused by reason of any prevention, delay, stoppage due to strikes, lockouts,
acts of God, or any other cause previously, or at such time, beyond the
reasonable control or anticipation of such party (collectively, a "FORCE
MAJEURE") and both parties' obligations under this Lease shall be forgiven and
suspended by any such Force Majeure; provided, however, that this Article 27 is
not intended to, and shall not, extend the time period for the payment of any
monetary amounts due (including, without limitation, rent payments from Tenant)
from either party to the other under this Lease nor relieve either party from
their monetary obligations to the other under this Lease.

                                  ARTICLE 28
                                  ----------

                                HAZARDOUS WASTE
                                ---------------

   (a) Tenant shall not cause or permit any Hazardous Material (as defined in
Article 28(c) below) to be brought, kept or used in or about the Project by
Tenant, its agents, employees, contractors, or invitees. Tenant indemnifies
Landlord from and against any breach by Tenant of the obligations stated in the
preceding sentence, and agrees to defend and hold Landlord harmless from and
against any and all claims, judgments, damages, penalties, fines, costs,
liabilities, or losses (including, without limitation, diminution in value of
the Project, damages for the loss or restriction or use of rentable or usable
space or of any amenity of the Project, damages arising from any adverse impact
or marketing of space in the Project, and sums paid in settlement of claims,
attorneys' fees and costs, consultant fees, and expert fees) which arise during
or after the Term of this Lease as a result of such breach. This indemnification
of Landlord by Tenant includes, without limitation, costs incurred in connection
with any investigation of site conditions or any cleanup, remedial, removal, or
restoration work required by any federal, state, or local governmental agency or
political subdivision because of Hazardous Material present in the soil or
ground water on or under the Project. Without limiting the foregoing, if the
presence of any Hazardous Material on the Project caused or permitted by Tenant
results in any contamination of the Project and subject to the provisions of
Articles 9, 10 and 11, hereof, Tenant shall promptly take all actions at its
sole expense as are necessary to return the Project to the condition existing
prior to the introduction of any such Hazardous Material and the contractors to
be used by Tenant for such work must be approved by Landlord, which approval
shall not be unreasonably withheld so long as such actions would not potentially
have any material adverse long-term or short-term effect on the Project and so
long as such actions do not materially interfere with the use and enjoyment of
the Project by the other tenants thereof.

   (b) It shall not be unreasonable for Landlord to withhold its consent to any
proposed Transfer if (i) the proposed transferee's anticipated use of the
Premises involves the generation, storage, use, treatment, or disposal of
Hazardous Material; (ii) the proposed Transferee has been required by any prior
landlord, lender, or governmental authority to take remedial action in
connection with Hazardous Material contaminating a property if the contamination
resulted from such Transferee's actions or use of the property in question; or
(iii) the proposed Transferee is subject to an enforcement order issued by any
governmental authority in connection with the use, disposal, or storage of a
Hazardous Material.

   (c) As used herein, the term "HAZARDOUS MATERIAL" means any hazardous or
toxic substance, material, or waste which is or becomes regulated by any local
governmental authority, the State of California or the United States Government.
The term "Hazardous Material" includes, without limitation, any material or
substance which is (i) defined as "Hazardous Waste," "Extremely Hazardous
Waste," or "Restricted Hazardous Waste" under Sections 25115, 25117 or 25122.7,
or listed pursuant to Section 25140, of the California Health and Safety Code,
Division 20, Chapter 6.5 (Hazardous Waste Control Law), (ii) defined as a
"Hazardous Substance" under Section 25316 of the California Health and Safety
Code, Division 20, Chapter 6.8 (Carpenter-Presley-Tanner Hazardous Substance
Account Act), (iii) defined as a "Hazardous Material," "Hazardous Substance," or
"Hazardous Waste" under Section 25501 of the California Health and Safety Code,
Division 20, Chapter 6.95 (Hazardous Materials Release Response

                                      -24-
<PAGE>

Plans and Inventory), (iv) defined as a "Hazardous Substance" under Section
25281 of the California Health and Safety Code, Division 20, Chapter 6.7
(Underground Storage of Hazardous Substances), (v) petroleum, (vi) asbestos,
(vii) listed under Article 9 or defined as Hazardous or extremely hazardous
pursuant to Article 11 of Title 22 of the California Administrative Code,
Division 4, Chapter 20, (viii) designated as a "Hazardous Substance" pursuant to
Section 311 of the Federal Water Pollution Control Act (33 U.S.C. (S) 1317),
(ix) defined as a "Hazardous Waste" pursuant to Section 1004 of the Federal
Resource Conservation and Recovery Act, 42 U.S.C. (S) 6901 et seq. (42 U.S.C.
(S) 6903), or (x) defined as a "Hazardous Substance" pursuant to Section 101 of
the Comprehensive Environmental Response, Compensation and Liability Act, 42
U.S.C. (S) 9601 et seq. (42 U.S.C. (S) 9601).

   (d) As used herein, the term "LAWS" mean any applicable federal, state or
local laws, ordinances, or regulations relating to any Hazardous Material
affecting the Project, including, without limitation, the laws, ordinances, and
regulations referred to in Article 28(c) above.

                                  ARTICLE 29
                                  ----------

                  SURRENDER OF PREMISES; REMOVAL OF PROPERTY
                  ------------------------------------------

   (a) The voluntary or other surrender of this Lease by Tenant to Landlord, or
a mutual termination hereof, shall not work a merger, and shall at the option of
Landlord, operate as an assignment to it of any or all subleases or subtenancies
affecting the Premises.

   (b) Upon the expiration of the Term of this Lease, or upon any earlier
termination of this Lease, Tenant shall quit and surrender possession of the
Premises to Landlord in as good order and condition as the same are now and
hereafter may be improved by Landlord or Tenant, reasonable wear and tear and
repairs which are Landlord's obligation excepted, and shall, without expense to
Landlord, remove or cause to be removed from the Premises all debris and
rubbish, all furniture, equipment, business and trade fixtures, free-standing
cabinet work, moveable partitioning, telephone and data cabling and other
articles of personal property owned by Tenant or installed or placed by Tenant
at its own expense in the Premises, and all similar articles of any other
persons claiming under Tenant unless Landlord exercises its option to have any
subleases or subtenancies assigned to it, and Tenant shall repair all damage to
the Premises resulting from the installation and removal of such items to be
removed.

   (c) Whenever Landlord shall reenter the Premises as provided in Article 12
hereof, or as otherwise provided in this Lease, any property of Tenant not
removed by Tenant upon the expiration of the Term of this Lease (or within
forty-eight (48) hours after a termination by reason of Tenant's default), as
provided in this Lease, shall be considered abandoned and Landlord may remove
any or all of such items and dispose of the same in any manner or store the
same in a public warehouse or elsewhere for the account and at the expense and
risk of Tenant, and if Tenant shall fail to pay the cost of storing any such
property after it has been stored for a period of ninety (90) days or more,
Landlord may sell any or all of such property at public or private sale, in
such manner and at such times and places as Landlord, in its sole discretion,
may deem proper, without notice or to demand upon Tenant, for the payment of
all or any part of such charges or the removal of any such property, and shall
apply the proceeds of such sale as follows: first, to the cost and expense of
such sale, including reasonable attorneys' fees for services rendered; second,
to the payment of the cost of or charges for storing any such property; third,
to the payment of any other sums of money which may then or thereafter be due
to Landlord from Tenant under any of the terms hereof; and fourth, the balance,
if any, to Tenant.

   (d) All fixtures, equipment, leasehold improvements, Alterations and/or
appurtenances attached to or built into the Premises prior to or during the
Term, whether by Landlord or Tenant and whether at the expense of Landlord or
Tenant, or of both, shall be and remain part of the Premises and shall not be
removed by Tenant at the end of the Term unless otherwise expressly provided for
in this Lease or unless such removal is required by Landlord as expressly
provided elsewhere in this Lease. Such fixtures, equipment, leasehold
improvements, Alterations, additions, improvements and/or appurtenances shall
include but not be limited to: all floor coverings, drapes, paneling, built-in
cabinetry, molding, doors, vaults (including vault doors), plumbing systems,
security systems, electrical systems, lighting systems, silencing equipment,
communication systems, all fixtures and outlets for the systems mentioned above
and for all telephone, radio, telegraph and television purposes, and any special
flooring or ceiling installations.

                                      -25-
<PAGE>

                                  ARTICLE 30
                                  ----------

                                 MISCELLANEOUS
                                 -------------

   (a) Severability; Entire Agreement. Any provision of this Lease which shall
prove to be invalid, void, or illegal shall in no way affect, impair or
invalidate any other provision hereof and such other provisions shall remain in
full force and effect. This Lease and the Exhibits and any Addendum attached
hereto constitute the entire agreement between the parties hereto with respect
to the subject matter hereof, and no prior agreement or understanding pertaining
to any such matter shall be effective for any purpose. No provision of this
Lease may be amended or supplemented except by an agreement in writing signed by
the parties hereto or their successor in interest.

   (b)  Attorneys' Fees; Waiver of Jury Trial.

        (i) In any action to enforce the terms of this Lease, including any suit
by Landlord for the recovery of rent or possession of the Premises, the losing
party shall pay the successful party a reasonable sum for attorneys' fees and
costs in such suit and such attorneys' fees and costs shall be deemed to have
accrued prior to the commencement of such action and shall be paid whether or
not such action is prosecuted to judgment.

        (ii) EACH PARTY HEREBY WAIVES ANY RIGHT TO A TRIAL BY JURY IN ANY ACTION
SEEKING SPECIFIC PERFORMANCE OF ANY PROVISION OF THIS LEASE, FOR DAMAGES FOR ANY
BREACH UNDER THIS LEASE, OR OTHERWISE FOR ENFORCEMENT OF ANY RIGHT OR REMEDY
HEREUNDER.

   (c) Time of Essence. Time is of the essence with respect to the performance
of every provision of this Lease.

   (d) Headings; Joint and Several. The article headings contained in this Lease
are for convenience only and do not in any way limit or amplify any term or
provision hereof. The terms "Landlord" and "Tenant" as used herein shall include
the plural as well as the singular, the neuter shall include the masculine and
feminine genders and the obligations herein imposed upon Tenant shall be joint
and several as to each of the persons, firms or corporations of which Tenant may
be composed.

   (e) Reserved Area. Tenant hereby acknowledges and agrees that the exterior
walls of the Premises and the area between the finished ceiling of the Premises
and the slab of the floor of the project thereabove have not been demised hereby
and the use thereof together with the right to install, maintain, use, repair
and replace pipes, ducts, conduits and wires leading through, under or above the
Premises in locations which will not materially interfere with Tenant's use of
the Premises and serving other parts of the Project are hereby excepted and
reserved unto Landlord.

   (f) NO OPTION. THE SUBMISSION OF THIS LEASE BY LANDLORD, ITS AGENT OR
REPRESENTATIVE FOR EXAMINATION OR EXECUTION BY TENANT DOES NOT CONSTITUTE AN
OPTION OR OFFER TO LEASE THE PREMISES UPON THE TERMS AND CONDITIONS CONTAINED
HEREIN OR A RESERVATION OF THE PREMISES IN FAVOR OF TENANT, IT BEING INTENDED
HEREBY THAT THIS LEASE SHALL ONLY BECOME EFFECTIVE UPON THE EXECUTION HEREOF BY
LANDLORD AND TENANT AND DELIVERY OF A FULLY EXECUTED LEASE TO TENANT.

   (g) Use of Project Name; Improvements. Tenant shall not be allowed to use the
name, picture or representation of the Project, or words to that effect, in
connection with any business carried on in the Premises or otherwise (except as
Tenant's address) without the prior written consent of Landlord. In the event
that Landlord undertakes any additional improvements on the Real Property
including but not limited to new construction or renovation or additions to the
existing improvements, Landlord shall not be liable to Tenant for any noise,
dust, vibration or interference with access to the Premises or disruption in
Tenant's business caused thereby.

                                      -26-
<PAGE>

   (h) Rules and Regulations. Tenant shall observe faithfully and comply
strictly with the Rules and Regulations attached to this Lease as Exhibit "B"
and made a part hereof, and such other Rules and Regulations as Landlord may
from time to time reasonably adopt for the safety, care and cleanliness of the
Project, the facilities thereof, or the preservation of good order therein.
Landlord shall not be liable to Tenant for violation of any such Rules and
Regulations, or for the breach of any covenant or condition in any lease by any
other tenant in the Project. A waiver by Landlord of any Rule or Regulation for
any other tenant shall not constitute nor be deemed a waiver of the Rule or
Regulation for this Tenant.

   (i) Quiet Possession. Upon Tenant's paying the Basic Rent, Additional Rent
and other sums provided hereunder and observing and performing all of the
covenants, conditions and provisions on Tenant's part to be observed and
performed hereunder, Tenant shall have quiet possession of the Premises for the
entire Term hereof, subject to all of the provisions of this Lease.

   (j)  Rent.  All payments required to be made hereunder to Landlord shall be
deemed to be rent, whether or not described as such.

   (k) Successors and Assigns. Subject to the provisions of Article 15 hereof,
all of the covenants, conditions and provisions of this Lease shall be binding
upon and shall inure to the benefit of the parties hereto and their respective
heirs, personal representatives, successors and assigns.

   (l) Notices. Any notice required or permitted to be given hereunder shall be
in writing and may be given by personal service evidenced by a signed receipt or
sent by registered or certified mail, return receipt requested, or via overnight
courier, and shall be effective upon proof of delivery, addressed to Tenant at
the Premises with a copy to Tenant at C-Bridge Internet Solutions, Inc., 219
Vassar Street, Cambridge, MA, 02139, Attn: Chief Counsel, Clifford B. Thompson
or to Landlord at the management office for the Project, with a copy to
Landlord, c/o Arden Realty, Inc., 11601 Wilshire Boulevard, Fourth Floor, Los
Angeles, California 90025, Attn: Legal Department. Either party may by notice to
the other specify a different address for notice purposes except that, upon
Tenant's taking possession of the Premises, the Premises shall constitute
Tenant's address for notice purposes. A copy of all notices to be given to
Landlord hereunder shall be concurrently transmitted by Tenant to such party
hereafter designated by notice from Landlord to Tenant. Any notices sent by
Landlord regarding or relating to eviction procedures, including without
limitation three day notices, may be sent by regular mail.

   (m) Access. Subject to Landlord's security requirements, repairs made by the
Landlord to the Project and Articles 16 and 18 above, Tenant shall have access
to the Premises twenty-four (24) hours per day, seven (7) days per week
throughout the Term.

   (n) Right of Landlord to Perform. All covenants and agreements to be
performed by Tenant under any of the terms of this Lease shall be performed by
Tenant at Tenant's sole cost and expense and without any abatement of rent. If
Tenant shall fail to pay any sum of money, other than rent, required to be paid
by it hereunder or shall fail to perform any other act on its part to be
performed hereunder, and such failure shall continue beyond any applicable cure
period set forth in this Lease, Landlord may, but shall not be obligated to,
without waiving or releasing Tenant from any obligations of Tenant, make any
such payment or perform any such other act on Tenant's part to be made or
performed as is in this Lease provided. All sums so paid by Landlord and all
reasonable incidental costs, together with interest thereon at the rate of ten
percent (10%) per annum from the date of such payment by Landlord, shall be
payable to Landlord on demand and Tenant covenants to pay any such sums, and
Landlord shall have (in addition to any other right or remedy of Landlord) the
same rights and remedies in the event of the nonpayment thereof by Tenant as in
the case of default by Tenant in the payment of the rent.

   (o)  Access, Changes in Project, Facilities, Name.

        (i) Every part of the Project except the inside surfaces of all walls,
windows and doors bounding the Premises (including exterior building walls, core
corridor walls and doors and any core corridor entrance), and any space in or
adjacent to the Premises used for shafts, stacks, pipes, conduits, fan rooms,
ducts, electric or other utilities, sinks or other building facilities, and the
use thereof, as well as access thereto through the Premises for the purposes of
operation, maintenance, decoration and repair, are reserved to Landlord.

                                      -27-
<PAGE>

        (ii) Landlord reserves the right, without incurring any liability to
Tenant therefor, to make such changes in or to the Project and the fixtures and
equipment thereof, as well as in or to the street entrances, halls, passages,
elevators, stairways and other improvements thereof, as it may deem necessary or
desirable.

        (iii) Landlord may adopt any name for the Project and Landlord reserves
the right to change the name or address of the Project at any time. (p) Signing
Authority. Concurrently with Tenant's execution of this Lease, Tenant shall
provide to Landlord reasonably satisfactory evidence that the individuals
executing this Lease on behalf of Tenant are authorized to bind Tenant and to
enter into this Lease.

   (q)  Intentionally Omitted.

   (r) Substitute Premises. Landlord shall have the right at any time during the
Term hereof, upon giving Tenant not less than sixty (60) days prior notice, to
provide and furnish Tenant with space elsewhere in the Project on the fourth
(4th) floor or higher and of approximately the same size as the Premises and
remove and place Tenant in such space, with Landlord to (i) improve such new
space to a level equivalent to that of the original Premises, (ii) pay for
Tenant to reprint a reasonable quantity of business stationery and for the
printing and mailing of a reasonable number of announcements of Tenant's new
address, and (iii) pay all other verified and previously approved costs and
expenses incurred as a result of such movement to such new space including,
without limitation, cabling and reconnection costs for Tenant's telephone, fax
and computer equipment. If Landlord moves Tenant to such new space, this Lease
and each and all of its terms, covenants and conditions shall remain in full
force and effect and shall be deemed applicable to such new space and such new
space shall thereafter be deemed to be the "Premises" as though Landlord and
Tenant had entered into an express written amendment of this Lease with respect
thereto.

   (s) Survival of Obligations. Any obligations of Tenant occurring prior to the
expiration or earlier termination of this Lease shall survive such expiration or
earlier termination.

   (t) Confidentiality. Tenant acknowledges that the content of this Lease and
any related documents are confidential information. Tenant shall keep such
confidential information strictly confidential and shall not disclose such
confidential information to any person or entity other than Tenant's financial,
legal and space planning consultants and any proposed subtenants or assignees.

   (u) Governing Law. This Lease shall be governed by and construed in
accordance with the laws of the State of California. No conflicts of law rules
of any state or country (including, without limitation, California conflicts of
law rules) shall be applied to result in the application of any substantive or
procedural laws of any state or country other than California. All
controversies, claims, actions or causes of action arising between the parties
hereto and/or their respective successors and assigns, shall be brought, heard
and adjudicated by the courts of the State of California, with venue in the
County of Los Angeles. Each of the parties hereto hereby consents to personal
jurisdiction by the courts of the State of California in connection with any
such controversy, claim, action or cause of action, and each of the parties
hereto consents to service of process by any means authorized by California law
and consent to the enforcement of any judgment so obtained in the courts of the
State of California on the same terms and conditions as if such controversy,
claim, action or cause of action had been originally heard and adjudicated to a
final judgment in such courts. Each of the parties hereto further acknowledges
that the laws and courts of California were freely and voluntarily chosen to
govern this Lease and to adjudicate any claims or disputes hereunder.

   (v) Exhibits and Addendum. The Exhibits and Addendum, if applicable, attached
hereto are incorporated herein by this reference as if fully set forth herein.

                                  ARTICLE 31
                                  ----------

                               OPTION TO EXTEND
                               ----------------

   (a) Option Right. Landlord hereby grants the Tenant named in this Lease (the
"ORIGINAL TENANT") one (1) option ("OPTION") to extend the Lease Term for the
entire Premises

                                      -28-
<PAGE>

for a period of five (5) years (an "OPTION TERM"), which option shall be
exercisable only by written notice delivered by Tenant to Landlord set forth
below. The rights contained in this Article 31 shall be personal to the Original
Tenant and any assignee of Tenant's entire interest in this Lease where such
assignment is made in accordance with Article 15 above ("PERMITTED ASSIGNEE")
and may only be exercised by the Original Tenant or such Permitted Assignee if
the Original Tenant or such Permitted Assignee occupies the entire Premises as
of the date of Tenant's Acceptance (as defined in Section 31(c) below).

   (b) Option Rent. The rent payable by Tenant during the Option Term ("OPTION
RENT") shall be equal to the "Market Rent" (defined below), but in no event
shall the Option Rent be less than Tenant is paying under the Lease on the month
immediately preceding the Option Term for Monthly Basic Rental, including all
escalations, Direct Costs, additional rent and other charges. "MARKET RENT"
shall mean the applicable Monthly Basic Rental, including all escalations,
Direct Costs, additional rent and other charges at which tenants, as of the time
of Landlord's "Option Rent Notice" (as defined below), are entering into leases
for non-sublease, non-encumbered, space comparable in size, location and quality
to the Premises in renewal transactions for a term comparable to the Option Term
which comparable space is located in office buildings comparable to the Project
in the West Los Angeles Area of California (but within a two (2) mile radius of
the Project), taking into consideration the value of the existing improvements
in the Premises to Tenant, as compared to the value of the existing improvements
in such comparable space, with such value to be based upon the age, quality and
layout of the improvements and the extent to which the same could be utilized by
Tenant with consideration given to the fact that the improvements existing in
the Premises are specifically suitable to Tenant.

   (c) Exercise of Option. The Option shall be exercised by Tenant only in the
following manner: (i) Tenant shall not be in default beyond the expiration of
any applicable cure period on the delivery date of the Interest Notice and
Tenant's Acceptance; (ii) Tenant shall deliver written notice ("INTEREST
NOTICE") to Landlord not more than twelve (12) months nor less than nine (9)
months prior to the expiration of the Lease Term, stating that Tenant is
interested in exercising the Option, (iii) within fifteen (15) business days of
Landlord's receipt of Tenant's written notice, Landlord shall deliver notice
("OPTION RENT NOTICE") to Tenant setting forth the Option Rent; and (iv) if
Tenant desires to exercise such Option, Tenant shall provide Landlord written
notice within ten (10) business days after receipt of the Option Rent Notice
("TENANT'S ACCEPTANCE'"). Tenant's failure to deliver the Interest Notice or
Tenant's Acceptance on or before the dates specified above shall be deemed to
constitute Tenant's election not to exercise the Option. If Tenant timely and
properly exercises its Option, the Lease Term shall be extended for the Option
Term upon all of the terms and conditions set forth in this Lease, except that
the rent for the Option Term shall be as indicated in the Option Rent Notice.

                                  ARTICLE 32
                                  ----------

                                   DIRECTORY
                                   ---------

     Tenant, at Tenant's sole cost and expense, shall have the right to one (1)
line in the lobby directory during the Lease Term.

                                      -29-
<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Lease, consisting of the
foregoing provisions and Articles, including all exhibits and other attachments
referenced therein, as of the date first above written.

"LANDLORD"                     ARDEN REALTY LIMITED PARTNERSHIP,
                               a Maryland limited partnership

                               By:  ARDEN REALTY, INC.
                                    a Maryland corporation
                                    Its:  Sole General Partner

                               By:  /s/
                                    ------------------------------------
                                    VICTOR J. COLEMAN
                                    Its:  President and COO

                               By:  /s/ Robert C. Peddiford
                                    ------------------------------------
                                    Its: Senior Vice President

"TENANT"                       C-BRIDGE INTERNET SOLUTIONS, INC.,
                               a Delaware corporation

                               By:  /s/
                                    ------------------------------------
                                    Print Name: Rick Wester
                                    Title: VP Finance

                               By:  /s/
                                    ------------------------------------
                                    Print Name: Clifford B. Thompson
                                    Title: VP & General Counsel

                                      -30-
<PAGE>

                                  EXHIBIT "A"
                                  -----------

                                   PREMISES
                                   --------

Rough drawing of Premises Omitted

                                  EXHIBIT "A"
                                      -1-
<PAGE>

                                  EXHIBIT "B"
                                  -----------

                             RULES AND REGULATIONS
                             ---------------------

   1. No sign, advertisement or notice shall be displayed, printed or affixed on
or to the Premises or to the outside or inside of the Project or so as to be
visible from outside the Premises or Project without Landlord's prior written
consent. Landlord shall have the right to remove any non-approved sign,
advertisement or notice, without notice to and at the expense of Tenant, and
Landlord shall not be liable in damages for such removal. All approved signs or
lettering on doors and walls shall be printed, painted, affixed or inscribed at
the expense of Tenant by Landlord or by a person selected by Landlord and in a
manner and style acceptable to Landlord.

   2.  Tenant shall not obtain for use on the Premises ice, waxing, cleaning,
interior glass polishing, rubbish removal, towel or other similar services, or
accept barbering or bootblackening, or coffee cart services, milk, soft drinks
or other like services on the Premises, except from persons authorized by
Landlord and at the hours and under regulations fixed by Landlord.  No vending
machines or machines of any description shall be installed, maintained or
operated upon the Premises without Landlord's prior written consent.

   3.  The sidewalks, halls, passages, exits, entrances, elevators and stairways
shall not be obstructed by Tenant or used for any purpose other than for ingress
and egress from Tenant's Premises.  Under no circumstances is trash to be stored
in the corridors.  Notice must be given to Landlord for any large deliveries.
Furniture, freight and other large or heavy articles, and all other deliveries
may be brought into the Project only at times and in the manner designated by
Landlord, and always at Tenant's sole responsibility and risk.  Landlord may
impose reasonable charges for use of freight elevators after or before normal
business hours.  All damage done to the Project by moving or maintaining such
furniture, freight or articles shall be repaired by Landlord at Tenant's
expense.  Tenant shall not take or permit to be taken in or out of entrances or
passenger elevators of the Project, any item normally taken, or which Landlord
otherwise reasonably requires to be taken, in or out through service doors or on
freight elevators.  Tenant shall move all supplies, furniture and equipment as
soon as received directly to the Premises, and shall move all waste that is at
any time being taken from the Premises directly to the areas designated for
disposal.

   4. Toilet rooms, toilets, urinals, wash bowls and other apparatus shall not
be used for any purpose other than for which they were constructed and no
foreign substance of any kind whatsoever shall be thrown therein.

   5.  Tenant shall not overload the floor of the Premises or mark, drive nails,
screw or drill into the partitions, ceilings or floor or in any way deface the
Premises.  Tenant shall not place typed, handwritten or computer generated signs
in the corridors or any other common areas.  Should there be a need for signage
additional to the Project standard tenant placard, a written request shall be
made to Landlord to obtain approval prior to any installation.  All costs for
said signage shall be Tenant's responsibility.

   6.  In no event shall Tenant place a load upon any floor of the Premises or
portion of any such flooring exceeding the floor load per square foot of area
for which such floor is designed to carry and which is allowed by law, or any
machinery or equipment which shall cause excessive vibration to the Premises or
noticeable vibration to any other part of the Project.  Prior to bringing any
heavy safes, vaults, large computers or similarly heavy equipment into the
Project, Tenant shall inform Landlord in writing of the dimensions and weights
thereof and shall obtain Landlord's consent thereto.  Such consent shall not
constitute a representation or warranty by Landlord that the safe, vault or
other equipment complies, with regard to distribution of weight and/or
vibration, with the provisions of this Rule 6 nor relieve Tenant from
responsibility for the consequences of such noncompliance, and any such safe,
vault or other equipment which Landlord determines to constitute a danger of
damage to the Project or a nuisance to other tenants, either alone or in
combination with other heavy and/or vibrating objects and equipment, shall be
promptly removed by Tenant, at Tenant's cost, upon Landlord's written notice of
such determination and demand for removal thereof.

                                  EXHIBIT "B"
                                      -1-
<PAGE>

   7.  Tenant shall not use or keep in the Premises or Project any kerosene,
gasoline or inflammable, explosive or combustible fluid or material, or use any
method of heating or air-conditioning other than that supplied by Landlord.

   8. Tenant shall not lay linoleum, tile, carpet or other similar floor
covering so that the same shall be affixed to the floor of the Premises in any
manner except as approved by Landlord.

   9.  Tenant shall not install or use any blinds, shades, awnings or screens in
connection with any window or door of the Premises and shall not use any drape
or window covering facing any exterior glass surface other than the standard
drapes, blinds or other window covering established by Landlord.

   10. Tenant shall cooperate with Landlord in obtaining maximum effectiveness
of the cooling system by closing window coverings when the sun's rays fall
directly on windows of the Premises. Tenant shall not obstruct, alter, or in any
way impair the efficient operation of Landlord's heating, ventilating and air-
conditioning system. Tenant shall not tamper with or change the setting of any
thermostats or control valves.

   11.  The Premises shall not be used for manufacturing or for the storage of
merchandise except as such storage may be incidental to the permitted use of the
Premises.  Tenant shall not, without Landlord's prior written consent, occupy or
permit any portion of the Premises to be occupied or used for the manufacture or
sale of liquor or tobacco in any form, or a barber or manicure shop, or as an
employment bureau.  The Premises shall not be used for lodging or sleeping or
for any improper, objectionable or immoral purpose.  No auction shall be
conducted on the Premises.

   12.  Tenant shall not make, or permit to be made, any unseemly or disturbing
noises, or disturb or interfere with occupants of Project or neighboring
buildings or premises or those having business with it by the use of any musical
instrument, radio, phonographs or unusual noise, or in any other way.

   13. No bicycles, vehicles or animals of any kind shall be brought into or
kept in or about the Premises, and no cooking shall be done or permitted by any
tenant in the Premises, except that the preparation of coffee, tea, hot
chocolate and similar items for tenants, their employees and visitors shall be
permitted. No tenant shall cause or permit any unusual or objectionable odors to
be produced in or permeate from or throughout the Premises. The foregoing
notwithstanding, Tenant shall have the right to use a microwave and to heat
microwavable items typically heated in an office. No hot plates, toasters,
toaster ovens or similar open element cooking apparatus shall be permitted in
the Premises.

   14. The sashes, sash doors, skylights, windows and doors that reflect or
admit light and air into the halls, passageways or other public places in the
Project shall not be covered or obstructed by any tenant, nor shall any bottles,
parcels or other articles be placed on the window sills.

   15.  No additional locks or bolts of any kind shall be placed upon any of the
doors or windows by any tenant, nor shall any changes be made in existing locks
or the mechanisms thereof unless Landlord is first notified thereof, gives
written approval, and is furnished a key therefor.  Each tenant must, upon the
termination of his tenancy, give to Landlord all keys and key cards of stores,
offices, or toilets or toilet rooms, either furnished to, or otherwise procured
by, such tenant, and in the event of the loss of any keys so furnished, such
tenant shall pay Landlord the cost of replacing the same or of changing the lock
or locks opened by such lost key if Landlord shall deem it necessary to make
such change.  If more than two keys for one lock are desired, Landlord will
provide them upon payment therefor by Tenant.  Tenant shall not key or re-key
any locks.  All locks shall be keyed by Landlord's locksmith only.

   16.  Landlord shall have the right to prohibit any advertising by any tenant
which, in Landlord's opinion, tends to impair the reputation of the Project or
its desirability as an office building and upon written notice from Landlord any
tenant shall refrain from and discontinue such advertising.

                                  EXHIBIT "B"
                                      -2-
<PAGE>

   17. Landlord reserves the right to control access to the Project by all
persons after reasonable hours of generally recognized business days and at all
hours on Sundays and legal holidays. Each tenant shall be responsible for all
persons for whom it requests after hours access and shall be liable to Landlord
for all acts of such persons. Landlord shall have the right from time to time to
establish reasonable rules pertaining to freight elevator usage, including the
allocation and reservation of such usage for tenants' initial move-in to their
premises, and final departure therefrom.

   18. Any person employed by any tenant to do janitorial work shall, while in
the Project and outside of the Premises, be subject to and under the control and
direction of the Office of the Project or its designated representative such as
security personnel (but not as an agent or servant of Landlord, and the Tenant
shall be responsible for all acts of such persons).

   19. All doors opening on to public corridors shall be kept closed, except
when being used for ingress and egress. Tenant shall cooperate and comply with
any reasonable safety or security programs, including fire drills and air raid
drills, and the appointment of "fire wardens" developed by Landlord for the
Project, or required by law. Before leaving the Premises unattended, Tenant
shall close and securely lock all doors or other means of entry to the Premises
and shut off all lights and water faucets in the Premises.

   20.  The requirements of tenants will be attended to only upon application to
the Office of the Project.

   21. Canvassing, soliciting and peddling in the Project are prohibited and
each tenant shall cooperate to prevent the same.

   22. All office equipment of any electrical or mechanical nature shall be
placed by tenants in the Premises in settings approved by Landlord, to absorb or
prevent any vibration, noise or annoyance.

   23. No air-conditioning unit or other similar apparatus shall be installed or
used by any tenant without the prior written consent of Landlord. Tenant shall
pay the cost of all electricity used for air-conditioning in the Premises if
such electrical consumption exceeds normal office requirements, regardless of
whether additional apparatus is installed pursuant to the preceding sentence.

   24.  There shall not be used in any space, or in the public halls of the
Project, either by any tenant or others, any hand trucks except those equipped
with rubber tires and side guards.

   25.  All electrical ceiling fixtures hung in offices or spaces along the
perimeter of the Project must be fluorescent and/or of a quality, type, design
and bulb color approved by Landlord.  Tenant shall not permit the consumption in
the Premises of more than 2 1/2 watts per net usable square foot in the Premises
in respect of office lighting nor shall Tenant permit the consumption in the
Premises of more than 1 1/2 watts per net usable square foot of space in the
Premises in respect of the power outlets therein, at any one time.  In the event
that such limits are exceeded, Landlord shall have the right to require Tenant
to remove lighting fixtures and equipment and/or to charge Tenant for the cost
of the additional electricity consumed.

   26.  Parking.

        (a) Project parking facility hours shall be 7:00 a.m. to 7:00 p.m.,
Monday through Friday, and closed on weekends, state and federal holidays
excepted, as such hours may be revised from time to time by Landlord.

        (b) Automobiles must be parked entirely within the stall lines on the
floor.

        (c) All directional signs and arrows must be observed.

        (d) The speed limit shall be 5 miles per hour.

        (e) Parking is prohibited in areas not striped for parking.

        (f) Parking cards or any other device or form of identification supplied
by Landlord (or its operator) shall remain the property of Landlord (or its
operator). Such parking

                                  EXHIBIT "B"
                                      -3-
<PAGE>

identification device must be displayed as requested and may not be mutilated in
any manner. The serial number of the parking identification device may not be
obliterated. Devices are not transferable or assignable and any device in the
possession of an unauthorized holder will be void. There will be a replacement
charge to the Tenant or person designated by Tenant of $25.00 for loss of any
parking card. There shall be a security deposit of $25.00 due at issuance for
each card key issued to Tenant.

        (g) The monthly rate for parking is payable one (1) month in advance
and must be paid by the third business day of each month.  Failure to do so will
automatically cancel parking privileges and a charge at the prevailing daily
rate will be due.  No deductions or allowances from the monthly rate will be
made for days parker does not use the parking facilities.

        (h) Tenant may validate visitor parking by such method or methods as
the Landlord may approve, at the validation rate from time to time generally
applicable to visitor parking.

        (i) Landlord (and its operator) may refuse to permit any person who
violates the within rules to park in the Project parking facility, and any
violation of the rules shall subject the automobile to removal from the Project
parking facility at the parker's expense.  In either of said events, Landlord
(or its operator) shall refund a prorata portion of the current monthly parking
rate and the sticker or any other form of identification supplied by Landlord
(or its operator) will be returned to Landlord (or its operator).

        (j) Project parking facility managers or attendants are not authorized
to make or allow any exceptions to these Rules and Regulations.

        (k) All responsibility for any loss or damage to automobiles or any
personal property therein is assumed by the parker.

        (l) Loss or theft of parking identification devices from automobiles
must be reported to the Project parking facility manager immediately, and a lost
or stolen report must be filed by the parker at that time.

        (m) The Parking facilities are for the sole purpose of parking one
automobile per space.  Washing, waxing, cleaning or servicing of any vehicles by
the parker or his agents is prohibited.

        (n) Landlord (and its operator) reserves the right to refuse the
issuance of monthly stickers or other parking identification devices to any
Tenant and/or its employees who refuse to comply with the above Rules and
Regulations and all City, State or Federal ordinances, laws or agreements.

        (o) Tenant agrees to acquaint all employees with these Rules and
Regulations.

        (p) No vehicle shall be stored in the Project parking facility for a
period of more than one (1) week.

   27. The Project is a non-smoking Project. Smoking or carrying lighted cigars
or cigarettes in the Premises or the Project, including the elevators in the
Project, is prohibited.

                                  EXHIBIT "B"
                                      -4-
<PAGE>

                                  EXHIBIT "C"
                                  -----------

                          NOTICE OF LEASE TERM DATES
                       AND TENANT'S PROPORTIONATE SHARE
                       --------------------------------

TO: _________________________________    DATE: ________________________________
_____________________________________
_____________________________________

RE:  Lease dated ________________, 2000, between ______________________________
     ___________________________ ("LANDLORD"), and ____________________________
     ___________________________ ("TENANT"), concerning Suite _______, located
     at __________________________________________.

Ladies and Gentlemen:

     In accordance with the Lease, Landlord wishes to advise and/or confirm the
following:

   1.  That the Premises have been accepted herewith by the Tenant as being
substantially complete in accordance with the Lease and that there is no
deficiency in construction.

   2. That the Tenant has taken possession of the Premises and acknowledges that
under the provisions of the Lease the Term of said Lease commenced on
___________(i.e., the Commencement Date under the Lease), the Abatement Period
expired on _________, and the Expiration Date shall be _____________.

   3.  That in accordance with the Lease, the Abatement Period expired on
_____________ and Basic Rental commenced to accrue on the day following the date
of expiration of the Abatement Period.

   4. If the date of expiration of the Abatement Period is other than the last
day of the month, the first billing will contain a prorata adjustment. Each
billing thereafter shall be for the full amount of the monthly installment as
provided for in said Lease.

   5.  Effective as of the day after the date of expiration of the Abatement
Period, rent is due and payable in advance on the first day of each and every
month during the Term of said Lease.  Your rent checks should be made payable to
________________________ at ________________________________________________.

   6. The exact number of rentable square feet within the Premises is __________
square feet.

   7.  Tenant's Proportionate Share, as adjusted based upon the exact number of
rentable square feet within the Premises is _______%.

AGREED AND ACCEPTED:

TENANT:

__________________________________,

a ________________________________

By: ______________________________
    Its: _________________________

                                 EXHIBIT ONLY
                       ***DO NOT SIGN - INITIAL ONLY***

                                  EXHIBIT "C"
                                      -1-
<PAGE>

                                  EXHIBIT "D"
                                  -----------

                              TENANT WORK LETTER
                              ------------------

     This Tenant Work Letter shall set forth the terms and conditions relating
to the renovation of the tenant improvements in the Premises.  This Tenant Work
Letter is essentially organized chronologically and addresses the issues of the
renovation of the Premises, in sequence, as such issues will arise.

                                   SECTION 1
                                   ---------

                LANDLORD'S INITIAL CONSTRUCTION IN THE PREMISES
                -----------------------------------------------

     Landlord has constructed, at its sole cost and expense, the base, shell and
core (i) of the Premises, and (ii) of the floor of the Project on which the
Premises is located (collectively, the "BASE, SHELL AND CORE").  Tenant has
inspected and hereby approves the condition of the Base, Shell and Core, and
agrees that the Base, Shell and Core shall be delivered to Tenant in its current
"as-is" condition.  The improvements to be initially installed in the Premises
shall be designed and constructed pursuant to this Tenant Work Letter.  Any
costs of initial design and construction of any improvements to the Premises
shall be an "Improvement Allowance Item", as that term is defined in Section 2.2
of this Tenant Work Letter.

                                   SECTION 2
                                   ---------

                                 IMPROVEMENTS
                                 ------------

     2.1  Improvement Allowance.  Tenant shall be entitled to a one-time
improvement allowance in the amount of $133,005 for the costs relating to the
initial design and construction of Tenant's improvements which are permanently
affixed to the Premises (the "IMPROVEMENTS") plus $1,330.05 for the initial
space plan (collectively, the "IMPROVEMENT ALLOWANCE").  Tenant shall have the
option, exercisable by written notice to Landlord on or before the Cost Proposal
Delivery Date, to increase the amount of the Improvement Allowance by up to Five
Dollars ($5.00) per usable square foot of the Premises.  If Tenant exercises
such option, monthly Basic Rental payable by Tenant throughout the five (5) year
period from the expiration of the Abatement Period until the Expiration Date
shall be increased by an amount sufficient to fully amortize such increase in
the Improvement Allowance throughout said five (5) year period based upon equal
monthly payments of principal and interest, with interest imputed on the
outstanding principal balance at the rate of eleven percent (11%) per annum and
the parties shall promptly execute an amendment to this Lease in order to
memorialize such increase in the Improvement Allowance and such increase in the
monthly Basic Rental.  In no event shall Landlord be obligated to make
disbursements pursuant to this Tenant Work Letter in a total amount which
exceeds the Improvement Allowance and in no event shall Tenant be entitled to
any credit for any unused portion of the Improvement Allowance not used by
Tenant by December 31, 2001.

     2.2  Disbursement of the Improvement Allowance.  Except as otherwise set
forth in this Tenant Work Letter, the Improvement Allowance shall be disbursed
by Landlord (each of which disbursements shall be made pursuant to Landlord's
disbursement process) for costs related to the construction of the Improvements
and for the following items and costs (collectively, the "IMPROVEMENT ALLOWANCE
ITEMS"): (i) payment of the fees of the "Architect" and the "Engineers," as
those terms are defined in Section 3.1 of this Tenant Work Letter, and payment
of the fees incurred by, and the cost of documents and materials supplied by,
Landlord and Landlord's consultants in connection with the preparation and
review of the "Construction Drawings," as that term is defined in Section 3.1 of
this Tenant Work Letter; (ii) the cost of permits; (iii) the cost of any changes
in the Base, Shell and Core required by the Construction Drawings; (iv) the cost
of any changes to the Construction Drawings or Improvements required by
applicable building codes (the "CODE"); and (v) the "Landlord Supervision Fee",
as that term is defined in Section 4.3.2 of this Tenant Work Letter.  However,
in no event shall more than Three and 00/100 Dollars ($3.00) per usable square
foot of the Tenant Improvement Allowance be used for the items described in (i)
and (ii) above; any additional amount incurred as a result of (i) and (ii) above
shall be deemed to constitute an Over-Allowance Amount.

                                  EXHIBIT "D"
                                      -1-
<PAGE>

     2.3  Standard Improvement Package.  Landlord has established specifications
(the "SPECIFICATIONS") for the Project standard components to be used in the
construction of the Improvements in the Premises (collectively, the "STANDARD
IMPROVEMENT PACKAGE"), which Specifications are available upon request.  The
quality of Improvements shall be equal to or of greater quality than the quality
of the Specifications, provided that Landlord may, at Landlord's option, require
the Improvements to comply with certain Specifications.

                                   SECTION 3
                                   ---------

                             CONSTRUCTION DRAWINGS
                             ---------------------

     3.1  Selection of Architect/Construction Drawings.  Tenant shall retain an
architect/space planner acceptable to Landlord (the "ARCHITECT ") to prepare the
"Construction Drawings," as that term is defined in this Section 3.1.  Tenant
shall also retain the engineering consultants designated by Landlord (the
"ENGINEERS ") to prepare all plans and engineering working drawings relating to
the structural, mechanical, electrical, plumbing, HVAC and lifesafety work of
the Tenant Improvements.  The plans and drawings to be prepared by Architect and
the Engineers hereunder shall be known collectively as the "CONSTRUCTION
DRAWINGS."  All Construction Drawings shall comply with the drawing format and
specifications as reasonably determined by Landlord, and shall be subject to
Landlord's reasonable approval.  Tenant and Architect shall verify, in the
field, the dimensions and conditions as shown on the relevant portions of the
base building plans, and Tenant and Architect shall be solely responsible for
the same, and Landlord shall have no responsibility in connection therewith.
Landlord's review of the Construction Drawings as set forth in this Section 3,
shall be for its sole purpose and shall not imply Landlord's review of the same,
or obligate Landlord to review the same, for quality, design, Code compliance or
other like matters.  Accordingly, notwithstanding that any Construction Drawings
are reviewed by Landlord or its space planner, architect, engineers and
consultants, and notwithstanding any advice or assistance which may be rendered
to Tenant by Landlord or Landlord's space planner, architect, engineers, and
consultants, Landlord shall have no liability whatsoever in connection therewith
and shall not be responsible for any omissions or errors contained in the
Construction Drawings.

     3.2  Final Space Plan.  On or before the date set forth in Schedule 1,
attached hereto, Tenant and the Architect shall prepare the final space plan for
Improvements in the Premises (collectively, the "FINAL SPACE PLAN"), which Final
Space Plan shall include a layout and designation of all offices, rooms and
other partitioning, their intended use, and equipment to be contained therein,
and shall deliver the Final Space Plan to Landlord for Landlord's approval.

     3.3  Final Working Drawings.  On or before the date set forth in Schedule
1, Tenant, the Architect and the Engineers shall complete the architectural and
engineering drawings for the Premises, and the final architectural working
drawings in a form which is complete to allow subcontractors to bid on the work
and to obtain all applicable permits (collectively, the "FINAL WORKING
DRAWINGS") and shall submit the same to Landlord for Landlord's approval.

     3.4  Permits.  The Final Working Drawings shall be approved by Landlord
(the "APPROVED WORKING DRAWINGS") prior to the commencement of the construction
of the Improvements.  Tenant shall cause the Architect to immediately submit the
Approved Working Drawings to the appropriate municipal authorities for all
applicable building permits necessary to allow "Contractor," as that term is
defined in Section 4.1, below, to commence and fully complete the construction
of the Improvements (the "PERMITS").  No changes, modifications or alterations
in the Approved Working Drawings may be made without the prior written consent
of Landlord, which consent shall not be unreasonably withheld.

     3.5  Time Deadlines.  Tenant shall use its best, good faith efforts and all
due diligence to cooperate with the Architect, the Engineers, and Landlord to
complete all phases of the Construction Drawings and the permitting process and
to receive the permits, and with Contractor for approval of the "Cost Proposal,"
as that term is defined in Section 4.2 of this Tenant Work Letter, as soon as
possible after the execution of the Lease, and, in that regard, shall meet with
Landlord on a scheduled basis to be determined by Landlord, to discuss Tenant's
progress in connection with the same.  The applicable dates for approval of
items, plans and drawings as described in this Section 3, Section 4 below, and
in this Tenant Work Letter are set forth and further elaborated upon in Schedule
1 (the "TIME DEADLINES"), attached hereto.  Tenant agrees to comply with the
Time Deadlines.

                                  EXHIBIT "D"
                                      -2-
<PAGE>

                                   SECTION 4
                                   ---------

                       CONSTRUCTION OF THE IMPROVEMENTS
                       --------------------------------

     4.1  Contractor.  The contractor which shall construct the Improvements
shall be a contractor designated by Landlord.  The contractor selected may be
referred to herein as the "CONTRACTOR".

     4.2  Cost Proposal.  After the Approved Working Drawings are signed by
Landlord and Tenant, Landlord shall provide Tenant with a cost proposal in
accordance with the Approved Working Drawings, which cost proposal shall
include, as nearly as possible, the cost of all Improvement Allowance Items to
be incurred by Tenant in connection with the construction of the Improvements
(the "COST PROPOSAL").  Tenant shall approve and deliver the Cost Proposal to
Landlord within three (3) business days of the receipt of the same, and upon
receipt of the same by Landlord, Landlord shall be released by Tenant to
purchase the items set forth in the Cost Proposal and to commence the
construction relating to such items.  The date by which Tenant must approve and
deliver the Cost Proposal to Landlord shall be known hereafter as the "COST
PROPOSAL DELIVERY DATE".

     4.3  Construction of Improvements by Contractor under the Supervision of
Landlord.

          4.3.1  Over-Allowance Amount.  On the Cost Proposal Delivery Date,
Tenant shall deliver to Landlord an amount (the "OVER-ALLOWANCE AMOUNT") equal
to the difference between (i) the amount of the Cost Proposal and (ii) the
amount of the Improvement Allowance (less any portion thereof already disbursed
by Landlord, or in the process of being disbursed by Landlord, on or before the
Cost Proposal Delivery Date).  The Over-Allowance Amount shall be disbursed by
Landlord prior to the disbursement of any then remaining portion of the
Improvement Allowance, and such disbursement shall be pursuant to the same
procedure as the Improvement Allowance.  In the event that, after the Cost
Proposal Delivery Date, any revisions, changes, or substitutions shall be made
to the Construction Drawings or the Improvements, any additional costs which
arise in connection with such revisions, changes or substitutions or any other
additional costs shall be paid by Tenant to Landlord immediately upon Landlord's
request as an addition to the Over-Allowance Amount.  Promptly after Substantial
Completion of the Improvements in the Premises, Landlord shall perform an
accounting to determine the total cost of the Improvement Allowance Items and,
to the extent Tenant has overpaid the Over-Allowance Amount, Landlord shall
refund such excess to Tenant within ten (10) days, or, if Tenant has underpaid
the Over-Allowance Amount, Tenant shall pay such shortfall to Landlord within
ten (10) days after Tenant's receipt of a reasonably particularized invoice.

          4.3.2  Landlord's Retention of Contractor.  Landlord shall
independently retain Contractor, on behalf of Tenant, to construct the
Improvements in accordance with the Approved Working Drawings and the Cost
Proposal and Landlord shall supervise the construction by Contractor, and Tenant
shall pay a construction supervision and management fee (the "LANDLORD
SUPERVISION FEE") to Landlord in an amount equal to the product of (i) three
percent (3%) and (ii) an amount equal to the Improvement Allowance plus the
Over-Allowance Amount (as such Over-Allowance Amount may increase pursuant to
the terms of this Tenant Work Letter).

                                   SECTION 5
                                   ---------

                        COMPLETION OF THE IMPROVEMENTS
                        ------------------------------

     5.1  Substantial Completion.  For purposes of this Lease, "SUBSTANTIAL
COMPLETION" of the Improvements in the Premises shall occur upon the completion
of construction of the Improvements in the Premises pursuant to the Approved
Working Drawings, with the exception of any punch list items and any tenant
fixtures, work-stations, built-in furniture, or equipment to be installed by
Tenant.

     5.2  Delay of the Substantial Completion of the Premises.  Except as
provided in this Section 5.2, the date of expiration of the Abatement Period and
Tenant's obligation to pay rent for the Premises shall occur as set forth in
Article 2 of the Lease.  However, if there shall be a delay or there are delays
in the Substantial Completion of the Improvements in the Premises as a result of
the following (collectively, "TENANT DELAYS"):

          5.2.1  Tenant's failure to comply with the Time Deadlines;

                                  EXHIBIT "D"
                                      -3-
<PAGE>

          5.2.2  Tenant's failure to timely approve any matter requiring
Tenant's approval;

          5.2.3  A breach by Tenant of the terms of this Tenant Work Letter or
the Lease;

          5.2.4  Changes in any of the Construction Drawings after disapproval
of the same by Landlord or because the same do not comply with Code or other
applicable laws;

          5.2.5  Tenant's request for changes in the Approved Working Drawings;

          5.2.6  Tenant's requirement for materials, components, finishes or
improvements which are not available in a commercially reasonable time given the
anticipated date of Substantial Completion of the Improvements in the Premises,
or which are different from, or not included in, the Standard Improvement
Package;

          5.2.7  Changes to the Base, Shell and Core required by the Approved
Working Drawings; or

          5.2.8  Any other acts or omissions of Tenant, or its agents, or
employees;

then, notwithstanding anything to the contrary set forth in the Lease or this
Tenant Work Letter and regardless of the actual date of the Substantial
Completion of Improvements in the Premises, the date of Substantial Completion
thereof shall be deemed to be the date that Substantial Completion would have
occurred if no Tenant Delay or Delays, as set forth above, had occurred.

                                   SECTION 6
                                   ---------

                                 MISCELLANEOUS
                                 -------------

     6.1  Tenant's Representative.  Tenant has designated Don Amaya or his
designee as its sole representative with respect to the matters set forth in
this Tenant Work Letter, who, until further notice to Landlord, shall have full
authority and responsibility to act on behalf of the Tenant as required in this
Tenant Work Letter.

     6.2  Landlord's Representative.  Prior to commencement of construction of
Improvements, Landlord shall designate a representative with respect to the
matters set forth in this Tenant Work Letter, who, until further notice to
Tenant, shall have full authority and responsibility to act on behalf of the
Landlord as required in this Tenant Work Letter.

     6.3  Time of the Essence in This Tenant Work Letter.  Unless otherwise
indicated, all references herein to a "number of days" shall mean and refer to
calendar days.

     6.4  Punch List.  Concurrently with Landlord's delivery of the Premises to
Tenant, a representative of Landlord and a representative of Tenant shall
perform a walk-through inspection of the Improvements in the Premises to
identify any "punch list" items (i.e., minor defects or conditions in such
Improvements that do not impair Tenant's ability to utilize the Premises for the
purposes permitted hereunder), which items Landlord shall repair or correct no
later than thirty (30) days after the date of such walk-through (unless the
nature of such repair or correction is such that more than thirty (30) days are
required for completion, in which case, Landlord shall commence such repair or
correction work within such thirty (30) day period and diligently prosecute the
same to completion).

                                  EXHIBIT "D"
                                      -4-
<PAGE>

                                  SCHEDULE 1
                                  ----------

                                TIME DEADLINES
                                --------------
<TABLE>
<CAPTION>
Dates                                        Actions to be Performed
------------------------------------------  --------------------------------------------------
<C> <C>                                      <S>
A.  May 26, 2000                             Tenant to deliver Final Space Plan to Landlord.

B.  June 12, 2000                            Tenant to deliver Final Working Drawings to
                                             Landlord.

C.  Three (3) business days after the        Tenant to approve Cost Proposal and deliver Cost
    receipt of the Cost Proposal by Tenant.  Proposal to Landlord.
</TABLE>

                                  SCHEDULE 1
                                      -1-
<PAGE>

                                  EXHIBIT "E"
                                  -----------

                               LETTER OF CREDIT
                               ----------------

Arden Realty Limited Partnership
6701 Center Drive West, Suite 1400
Los Angeles, California 90045
Attention: Property Manager

Ladies and Gentlemen:

     We hereby establish in your favor, for the account of C-Bridge Internet
Solutions, Inc., a Delaware corporation ("APPLICANT"), our Irrevocable Letter of
Credit and authorize you to draw on us at sight the aggregate amount of Three
Hundred Sixty-Four Thousand Five Hundred Fifty-Eight and 58/100 Dollars
($364,558.58) ("STATED AMOUNT").

     Funds under this Letter of Credit are available to Arden Realty Limited
Partnership, a Maryland limited partnership (the "BENEFICIARY") as follows:

     Any and all of the sums hereunder may be drawn down at any time and from
time to time from and after the date hereof by Beneficiary when accompanied by
this Letter of Credit and a written certification signed by an authorized
signatory of Beneficiary certifying that such sums are due and owing to
Beneficiary as a result of a default by Applicant with respect to any provision
of that certain Standard Office Lease dated May 11, 2000 ("LEASE") by and
between Beneficiary, as Landlord, and Applicant, as Tenant, together with a
notarized certification by any such individual representing that such individual
is authorized by Beneficiary to take such action on behalf of Beneficiary.  The
sums drawn by Beneficiary under this Letter of Credit shall be payable upon
demand without necessity of notice to the Applicant.  Partial drawings shall be
permitted.

     Subject to our receipt of a written authorization signed by an authorized
signatory of Beneficiary, the Stated Amount of this Letter of Credit shall be
reduced to the following amounts at the following times:
<TABLE>
<CAPTION>
     Date         Stated Amount
---------------  ----------------
<S>              <C>
July 31, 2001      $291,646.86
July 31, 2002      $218,735.14
July 31, 2003      $145,823.42
July 31, 2004      $ 72,911.72
</TABLE>

     This Letter of Credit is transferable in its entirety.  Should a transfer
be desired, such transfer will be subject to the return to us of this Letter of
Credit, together with written instructions.

     The amount of each draft must be endorsed on the reverse hereof by the
negotiating bank.  We hereby agree that this Letter of Credit shall be duly
honored upon presentation and delivery of the certification specified above.

     This Letter of Credit shall expire on September 30, 2005.

     Notwithstanding the above expiration of this Letter of Credit, the term of
this Letter of Credit shall be automatically renewed for successive, additional
one (1) year periods unless, at least thirty (30) days prior to any such date of
expiration, the undersigned shall give written notice to Beneficiary, by
certified mail, return receipt requested and at the address set forth above or
at such other address as may be given to the undersigned by Beneficiary, that
this Letter of Credit will not be renewed.

                                  EXHIBIT "E"
                                      -1-
<PAGE>

     This Letter of Credit is governed by the Uniform Customs and Practice for
Documentary Credits (1993 Revision), International Chamber of Commerce
Publication 500.

                              Very truly yours,

                              (Name of Issuing Bank)

                              By: ____________________________________________

                                 EXHIBIT ONLY
                       ***DO NOT SIGN - INITIAL ONLY***

                                  EXHIBIT "E"
                                      -2-<PAGE>

                                LEASE AGREEMENT

                                    between

                       125 SUMMER STREET CORNERSTONE LLC

                                 as "Landlord"

                                      and

                       C-BRIDGE INTERNET SOLUTIONS, INC.

                                  as "Tenant"
<PAGE>

                               TABLE OF CONTENTS
                               -----------------
<TABLE>
<CAPTION>
                                                                        Page
                                                                        ----
<S>                                                                     <C>
1.   PREMISES...........................................................   1
2.   TERM; POSSESSION...................................................   1
3.   RENT...............................................................   1
4.   SECURITY DEPOSIT...................................................   6
5.   USE AND COMPLIANCE WITH LAWS.......................................   7
6.   TENANT IMPROVEMENTS & ALTERATIONS..................................   9
7.   MAINTENANCE AND REPAIRS............................................  10
8.   TENANT'S TAXES.....................................................  12
9.   UTILITIES AND SERVICES.............................................  12
10.  EXCULPATION AND INDEMNIFICATION....................................  14
11.  INSURANCE..........................................................  15
12.  DAMAGE OR DESTRUCTION..............................................  17
13.  CONDEMNATION.......................................................  18
14.  ASSIGNMENT AND SUBLETTING..........................................  20
15.  DEFAULT AND REMEDIES...............................................  20
16.  LATE CHARGE AND INTEREST...........................................  26
17.  WAIVER.............................................................  27
18.  ENTRY, INSPECTION AND CLOSURE......................................  27
19.  SURRENDER AND HOLDING OVER.........................................  28
20.  ENCUMBRANCES.......................................................  29
21.  ESTOPPEL CERTIFICATES AND FINANCIAL STATEMENTS.....................  29
22.  NOTICES............................................................  30
23.  ATTORNEYS' FEES....................................................  30
24.  QUIET POSSESSION...................................................  31
25.  SECURITY MEASURES..................................................  31
26.  FORCE MAJEURE......................................................  31
27.  RULES AND REGULATIONS..............................................  31
28.  LANDLORD'S LIABILITY...............................................  32
29.  CONSENTS AND APPROVALS.............................................  32
30.  WAIVER OF RIGHT TO JURY TRIAL......................................  32
31.  BROKERS............................................................  32
32.  RELOCATION OF PREMISES.............................................  33
33.  ENTIRE AGREEMENT...................................................  33
34.  MISCELLANEOUS......................................................  33
35.  AUTHORITY..........................................................  34
36.  VACANCY DURING LAST SIX MONTHS.....................................  35
</TABLE>

                                       i
<PAGE>

                             INDEX OF DEFINED TERMS
                             ----------------------
<TABLE>
<CAPTION>
                                                                        Page
                                                                        ----
<S>                                                                     <C>
Additional Rent........................................................   4
Alterations............................................................   8
Award..................................................................  16
Base Operating Costs...................................................   2
Base Rent..............................................................   1
Base Taxes.............................................................   2
Broker.................................................................  27
Building...............................................................   1
Building Rules.........................................................  26
Building Systems.......................................................   6
Business Days..........................................................  11
Business Hours.........................................................  11
Commencement Date......................................................   1
Condemnation...........................................................  16
Condemnor..............................................................  16
Construction Rider.....................................................   1
Controls...............................................................  10
Date of Condemnation...................................................  16
Encumbrance............................................................  23
Environmental Losses...................................................   6
Environmental Requirements.............................................   6
Event of Default.......................................................  19
Expiration Date........................................................   1
Fees...................................................................  25
Handled by Tenant......................................................   6
Handling by Tenant.....................................................   6
Hazardous Materials....................................................   6
HVAC...................................................................   6
Interest Rate..........................................................  21
Landlord...............................................................   1
Laws...................................................................   2
Mortgagee..............................................................  24
Operating Costs........................................................   2
Parking Facility.......................................................   1
Permitted Hazardous Materials..........................................   7
Premises...............................................................   1
Project................................................................   1
Property...............................................................   1
Property Manager.......................................................  13
Proposed Transferee....................................................  17
Rent...................................................................   5
</TABLE>

                                      ii
<PAGE>

<TABLE>
<S>                                                                      <C>
Rental Tax.............................................................  10
Representatives........................................................   6
Scheduled Commencement Date............................................   1
Security Deposit.......................................................   5
Service Failure........................................................  11
Substantially Completed................................................   1
Taxes..................................................................   3
Tenant.................................................................   1
Tenant's Share.........................................................   3
Tenant's Taxes.........................................................  10
Tenant Delay...........................................................   1
Tenant Improvements....................................................   8
Term...................................................................   1
Trade Fixtures.........................................................   9
Transfer...............................................................  17
Transferee.............................................................  18
Visitors...............................................................   6
</TABLE>

                                      iii
<PAGE>

                            BASIC LEASE INFORMATION
                            -----------------------

Lease Date:              For identification purposes only, the date
                         of this Lease is March 24, 2000

Landlord:                125 Summer Street Cornerstone LLC, a
                         Delaware limited liability company

Tenant:                  C-Bridge Internet Solutions, Inc., a
                         Delaware corporation

Project:                 125 Summer Street

Building Address:        125 Summer Street, Boston, MA 02110

Rentable Area of         463,691 rentable square feet
Building:

Premises:                Floor:         19
                         Suite Number:  Not Applicable.
                         Rentable Area: 19,682 rentable square feet

Term:                    84 full calendar months (plus any partial
                         month at the beginning of the Term)

Scheduled                June 15, 2000
Commencement Date:

Expiration Date:         The last day of the seventh (7/th/) Lease Year.
                         The term "Lease Year" shall mean
                         any twelve (12) calendar month period
                         commencing on the Term Commencement Date or
                         on any anniversary thereof (plus any partial
                         month at the end of the Term).

Base Rent:               $46.00 PSF of Rentable Area in the Premises
                         for Lease Year 1 through Lease Year 3;

                         $48.00 PSF of Rentable Area in the Premises
                         for Lease Year 4; and

                         $50.00 PSF of Rentable Area in the Premises
                         for Lease Year 5 through Lease Year 7

Base Year                Calendar year 1999 for Operating Costs

                         Fiscal year 2000 for Taxes

                                       1
<PAGE>

Tenant's Share:                See Section 3.2(a)

Security Deposit:              $150,895.00, plus Letter of Credit pursuant
                               to Exhibit E

Landlord's Address for         125 Summer Street Cornerstone LLC
Payment of Rent:               P.O. Box 35334
                               Newark Post Office
                               Newark, NJ 07193-5334

Business Hours:                8:00 A.M. to 6:00 P.M.

Landlord's Address for         125 Summer Street Cornerstone LLC
Notices:                       c/o Cornerstone Properties, Inc.
                               125 Summer Street
                               Boston, MA 02110

                               with a copy to:

                               Wilson Cornerstone Properties
                               2929 Campus Drive, 4th Floor
                               San Mateo, CA 94403
                               Attention:  General Counsel

Tenant's Address for           C-Bridge Internet Solutions, Inc.
Notices:                       219 Vassar Street
                               Cambridge, MA 02139

Access Card Deposit:           $25 per card

Broker(s):                     Meredith & Grew, Inc. and Grubb & Ellis
                               Company

Guarantor(s):                  None.

Property Manager:              Cornerstone Properties, Inc.
                               or such other manager as Landlord may from
                               time to time designate

Additional Provisions:         See Exhibit E

                               1.    Parking

                               2.    Extension Option

                               3.    Right of First Offer

                               4.    Letter of Credit

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Exhibits:
--------

Exhibit A:     The Premises
Exhibit B:     Construction Rider
Exhibit C:     Building Rules
Exhibit D:     Landlord Services
Exhibit E:     Additional Provisions
Exhibit F:     Form of Letter of Credit

     The Basic Lease Information set forth above is part of the Lease. In the
event of any conflict between any provision in the Basic Lease Information and
the Lease, the Lease shall control.

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<PAGE>

     THIS LEASE is made as of the Lease Date set forth in the Basic Lease
Information, by and between the Landlord identified in the Basic Lease
Information ("Landlord"), and the Tenant identified in the Basic Lease
Information ("Tenant"). Landlord and Tenant hereby agree as follows:

1.   PREMISES. Landlord hereby leases to Tenant, and Tenant hereby leases from
Landlord, upon the terms and subject to the conditions of this Lease, the office
space identified in the Basic Lease Information as the Premises (the
"Premises"), in the Building located at the address specified in the Basic Lease
Information (the "Building"). The approximate configuration and location of the
Premises is shown on Exhibit A. Landlord and Tenant agree that the rentable area
                     ---------
of the Premises for all purposes under this Lease shall be the Rentable Area
specified in the Basic Lease Information. The Building, together with the
parking facilities serving the Building (the "Parking Facility"), and the
parcel(s) of land on which the Building and the Parking Facility are situated
(collectively, the "Property"), is part of the Project identified in the Basic
Lease Information (the "Project").

2.   TERM; POSSESSION. The term of this Lease (the "Term") shall commence on the
Commencement Date as described below and, unless sooner terminated, shall expire
on the Expiration Date set forth in the Basic Lease Information (the "Expiration
Date"). The "Commencement Date" shall be the earlier of (a) the date on which
Landlord tenders possession of the Premises to Tenant, with all of Landlord's
construction obligations, if any, "Substantially Completed" as provided in the
Construction Rider attached as Exhibit B (the "Construction Rider") or, in the
                               ---------
event of any "Tenant Delay," as defined in the Construction Rider, the date on
which Landlord could have done so had there been no such Tenant Delay; or (b)
the date upon which Tenant, with Landlord's written permission, actually
occupies and conducts business in any portion of the Premises. The parties
anticipate that the Commencement Date will occur on or about the Scheduled
Commencement Date set forth in the Basic Lease Information (the "Scheduled
Commencement Date"); provided, however, that Landlord shall not be liable for
any claims, damages or liabilities if the Premises are not ready for occupancy
by the Scheduled Commencement Date. When the Commencement Date has been
established, Landlord and Tenant shall at the request of either party confirm
the Commencement Date and Expiration Date in writing.

3.   RENT.

     3.1. Base Rent. Tenant agrees to pay to Landlord the Base Rent set forth in
          ---------
the Basic Lease Information (the "Base Rent"), without prior notice or demand,
in equal monthly installments on the first day of each and every calendar month
during the Term, except that Base Rent for the first full calendar month in
which Base Rent is payable shall be paid upon Tenant's execution of this Lease
and Base Rent for any partial month at the beginning of the Term shall be paid
on the Commencement Date. Base Rent for any partial month at the beginning or
end of the Term shall be prorated based on the actual number of days in the
month.

     If the Basic Lease Information provides for any change in Base Rent by
reference to years or months (without specifying particular dates), the change
will take effect on the applicable annual

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<PAGE>

or monthly  anniversary of the Commencement  Date (which will not necessarily be
the first day of a calendar month).

     3.2. Additional Rent: Increases in Operating Costs and Taxes.
          -------------------------------------------------------

          (a)  Definitions.
               -----------

               (1)  "Base Operating Costs" means Operating Costs for the
calendar year specified in the Basic Lease Information.

               (2)  "Base Taxes" means Taxes for the fiscal year specified in
 the Basic Lease Information.

               (3)  "Operating Costs" means all costs of managing, operating,
maintaining and repairing the Property, including all costs, expenditures, fees
and charges for: (A) operation, maintenance and repair of the Property
(including maintenance, repair and replacement of glass, the roof covering or
membrane, and landscaping); (B) utilities and services (including
telecommunications facilities and equipment, recycling programs, trash removal,
and snow and ice removal), and associated supplies and materials; (C)
compensation (including employment taxes and fringe benefits) for persons who
perform duties in connection with the operation, management, maintenance and
repair of the Building, such compensation to be appropriately allocated for
persons who also perform duties unrelated to the Building; (D) property
(including coverage for earthquake and flood if carried by Landlord), liability,
rental income and other insurance relating to the Property, and expenditures for
commercially reasonable deductible amounts paid under such insurance; (E)
licenses, permits and inspections; (F) complying with the requirements of any
law, statute, ordinance or governmental rule or regulation or any orders
pursuant thereto (individually a "Law" and collectively "Laws"); (G)
amortization of capital improvements required to comply with Laws, or which are
intended to reduce Operating Costs or improve the utility, efficiency or
capacity of any Building System, with interest on the unamortized balance at the
rate paid by Landlord on funds borrowed to finance such capital improvements
(or, if Landlord finances such improvements out of Landlord's funds without
borrowing, the rate that Landlord would have paid to borrow such funds, as
reasonably determined by Landlord), over such useful life (or, if Landlord so
elects, over such shorter period during which the cost savings resulting from
the capital improvement equal the total cost of the improvement) as Landlord
shall reasonably determine; (H) an office in the Project for the management of
the Property, including expenses of furnishing and equipping such office and the
rental value of any space occupied for such purposes; (I) property management
fees; (J) accounting, legal and other professional services incurred in
connection with the operation of the Property and the calculation of Operating
Costs and Taxes; (K) a reasonable allowance for depreciation on machinery and
equipment used to maintain the Property and on other personal property owned by
Landlord in the Property (including window coverings and carpeting in common
areas); (L) contesting the validity or applicability of any Laws that may affect
the Property; (M) the Building's share of any shared or common area maintenance
fees and expenses (including costs and expenses of operating, managing, owning
and maintaining the Parking Facility and the common areas of the Project and
amenities serving tenants generally); and (N) any other cost, expenditure, fee
or charge, whether or not hereinbefore

                                       2
<PAGE>

described,  which in accordance  with  generally  accepted  property  management
practices would be considered an expense of managing, operating, maintaining and
repairing  the  Property.  Operating  Costs for any  calendar  year during which
average  occupancy of the Building is less than one hundred percent (100%) shall
be calculated  based upon the  Operating  Costs that would have been incurred if
the Building had an average  occupancy of one hundred  percent (100%) during the
entire calendar year.

Notwithstanding the foregoing, Operating Costs shall not include (i) capital
improvements (except as otherwise provided above); (ii) costs of special
services rendered to individual tenants (including Tenant) for which a special
charge is made; (iii) interest, principal payments, points and fees on loans or
indebtedness secured by the Building; (iv) costs of improvements for Tenant or
other tenants of the Building; (v) costs of services or other benefits of a type
which are not available to Tenant but which are available to other tenants or
occupants, and costs for which Landlord is reimbursed by other tenants of the
Building (e.g., tenant electricity) other than through payment of tenants'
shares of increases in Operating Costs and Taxes; (vi) leasing commissions,
advertising costs, attorneys' fees and other expenses incurred in connection
with leasing space in the Building or enforcing such leases; (vii) depreciation
or amortization, other than as specifically enumerated in the definition of
Operating Costs above; (viii) costs, fines or penalties incurred due to
Landlord's violation of any Law; (ix) any costs or expenses incurred by Landlord
in the original construction and development of the Building; (x) costs required
to remedy any noncompliance, as of the date hereof, of the Building with
applicable Law (including, without limitation, the Americans with Disabilities
Act of 1990); (xi) costs relating to maintaining Landlord's existence as a
corporation, limited partnership or other entity; (xii) ground lease payments,
and any other costs related to ground leases; (xiii) any bad debt loss, rent
loss, or reserves for bad debt or rent loss; (xiv) interest or penalties
incurred as a result of Landlord's negligence, willful misconduct or breach of
contract; (xv) salaries of executives or principals of Landlord above the level
of senior property manager (except to the extent the same may be reflected in
any management or building services fee for the Project or attributable to
actual Project management or operations); (xvi) the day-to-day expenses of
cleaning, operating, and maintaining the Parking Facility; (xvii) costs incurred
by Landlord for the repair of damage to the Building, to the extent Landlord is
reimbursed by insurance proceeds; and (xviii) any charitable or political
contributions by Landlord;.

                    (4)  "Taxes" means all taxes, assessments, betterments,
excises, user fees and all other governmental charges and fees of any kind or
nature, or impositions or agreed payments in lieu thereof or voluntary payments
made in connection with the provision of governmental services or improvements
of benefit to the Property (including any so-called linkage, impact or voluntary
betterment payments), and all penalties and interest thereon (if due to Tenant's
failure to make timely payments on account of Taxes), assessed or imposed
against the Premises or the Property of which the Premises are a part (including
without limitation any personal property taxes levied on such Property or on
fixtures or equipment used in connection therewith), or upon Landlord by virtue
of its ownership thereof, other than a federal or state income tax of general
application. If during the Term the present system of ad valorem taxation of
property shall be changed so that, in lieu of or in addition to the whole or any
part of such ad valorem tax, there shall be assessed, levied or imposed on such
Property or Premises or on Landlord any kind or nature of

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<PAGE>

federal, state, county, municipal or other governmental capital levy, income,
sales, franchise, excise or similar tax, assessment, levy, charge or fee (as
distinct from the federal and state income tax in effect on the Commencement
Date) measured by or based in whole or in part upon Property valuation, mortgage
valuation, rents or any other incidents, benefits or measures of real property
or real property operations, then any and all of such taxes, assessments,
levies, charges and fees (to the extent levied, assessed or imposed with respect
to the Property) shall be included within the term Taxes. For all real estate
taxes (other than assessments payable in installments, for which Taxes for the
year shall include the installments and any applicable interest due and payable
during such year), Taxes for the year shall, at Landlord's election, include
either the amount accrued, assessed, or imposed for such year or the amount due
and payable for that year, provided that such determination of Taxes shall be
applied consistently to Tenant throughout the Term. Taxes also include
reasonable expenses, including fees of attorneys, appraisers and other
consultants, incurred in connection with any efforts to obtain abatements or
reductions or to assure maintenance of Taxes for any tax fiscal year wholly or
partially included in the Term, whether or not successful and whether or not
such efforts involve filing of actual abatement applications or initiation of
formal proceedings.

                    (5)  "Tenant's Share" means the Rentable Area of the
Premises divided by ninety-five percent (95%) of the total Rentable Area of the
Building (or, if greater, the Rentable Area of the Building occupied), as set
forth in the Basic Lease Information. If the Rentable Area of the Building is
changed or the Rentable Area of the Premises is changed by Tenant's leasing of
additional space hereunder or for any other reason, Tenant's Share shall be
adjusted accordingly.

               (b)  Additional Rent.
                    ---------------

                    (1)  Tenant shall pay Landlord as "Additional Rent" for each
calendar year or portion thereof during the Term Tenant's Share of the sum of
(x) the amount (if any) by which Operating Costs for such period exceed Base
Operating Costs, and (y) the amount (if any) by which Taxes for such period
exceed Base Taxes.

                    (2)  Prior to the end of each calendar year, Landlord shall
notify Tenant of Landlord's good faith estimate of Operating Costs, Taxes and
Tenant's Additional Rent for the following calendar year. Commencing on the
first day of January of each calendar year and continuing on the first day of
every month thereafter in such year, Tenant shall pay to Landlord one-twelfth
(1/12th) of the estimated Additional Rent. If Landlord thereafter reasonably
estimates during the course of such calendar year that Operating Costs or Taxes
for such year will vary from Landlord's prior estimate, Landlord may, by notice
to Tenant, revise the estimate for such year (and Additional Rent shall
thereafter be payable based on the revised estimate).

                    (3)  As soon as reasonably practicable after the end of each
calendar year, Landlord shall furnish Tenant a statement with respect to such
year, showing Operating Costs, Taxes and Additional Rent for the year, and the
total payments made by Tenant with respect thereto. Unless Tenant gives notice
of any objections to Landlord's statement within six (6) months after receipt of
the same, such statement shall conclusively be deemed correct and Tenant shall
have no right thereafter to dispute such statement or any item therein or the
computation of

                                       4
<PAGE>

Additional Rent based thereon. If Tenant does object to such statement, then
Landlord shall provide Tenant with reasonable verification of the figures shown
on the statement and the parties shall negotiate in good faith to resolve any
disputes. Any objection of Tenant to Landlord's statement and resolution of any
dispute shall not postpone the time for payment of any amounts due Tenant or
Landlord based on Landlord's statement, nor shall any failure of Landlord to
deliver Landlord's statement in a timely manner relieve Tenant of Tenant's
obligation to pay any amounts due Landlord based on Landlord's statement.

                    (4)  If Tenant's Additional Rent as finally determined for
any calendar year exceeds the total payments made by Tenant on account thereof,
Tenant shall pay Landlord the deficiency within thirty (30) days of Tenant's
receipt of Landlord's statement. If the total payments made by Tenant on account
thereof exceed Tenant's Additional Rent as finally determined for such year,
Tenant's excess payment shall be credited toward the rent next due from Tenant
under this Lease. For any partial calendar year at the beginning or end of the
Term, Additional Rent shall be prorated on the basis of a 365-day year by
computing Tenant's Share of the increases in Operating Costs and Taxes for the
entire year and then prorating such amount for the number of days during such
year included in the Term. Notwithstanding the termination of this Lease,
Landlord shall pay to Tenant or Tenant shall pay to Landlord, as the case may
be, within thirty (30) days after Tenant's receipt of Landlord's final statement
for the calendar year in which this Lease terminates, the difference between
Tenant's Additional Rent for that year, as finally determined by Landlord, and
the total amount previously paid by Tenant on account thereof.

     If for any reason Taxes for any year during the Term are reduced, refunded
or otherwise changed, Tenant's Additional Rent shall be adjusted accordingly. If
Taxes are temporarily reduced as a result of space in the Building being leased
to a tenant that is entitled to an exemption from property taxes or other taxes,
then for purposes of determining Additional Rent for each year in which Taxes
are reduced by any such exemption, Taxes for such year shall be calculated on
the basis of the amount the Taxes for the year would have been in the absence of
the exemption. The obligations of Landlord to refund any overpayment of
Additional Rent and of Tenant to pay any Additional Rent not previously paid
shall survive the expiration of the Term.

                    (5)  Provided that no Event of Default (or condition as to
which Tenant has received notice, which with the passage of time, would
constitute an Event of Default) then exists, Tenant shall have the right to
audit Landlord's annual statement concerning Operating Costs and Taxes for the
year just ended, subject to and in accordance with this Section 3(b)(5). Any
request by Tenant to conduct such an audit shall be made by written notice
delivered to Landlord not later than ninety (90) days after Tenant's receipt of
such annual statement, specifying the items in such annual statement that Tenant
desires to audit. Any such audit shall be conducted by a certified public
accountant from one of the six largest national accounting firms. Before the
commencement of any such audit, Tenant and its accountant shall also enter into
a confidentiality agreement with Landlord, in a form reasonably supplied by
Landlord, certifying that Tenant has not engaged any person or firm on a
contingency fee basis in connection with this audit and agreeing to restrict the
use of all information solely to the determination of Tenant's Proportionate
Share of Operating Cost and Taxes under this Lease. At least ten (10) business
days prior to commencement of the audit, Tenant shall provide Landlord

                                       5
<PAGE>

with a list of requested information. The accountant's field work shall take
place during business hours in the offices of Landlord or its building manager
(or in another location specified by Landlord in Boston, Massachusetts) and
shall be completed within no more than five (5) business days commencing on the
date that such access is first made available to Tenant. Access shall be limited
to the records evidencing the Operating Costs and Taxes allocable to the
Premises that were used by Landlord in preparing such annual statement. Copies
of any documents requested by Tenant shall be made by Landlord at Tenant's
expense. Tenant shall furnish Landlord with a copy of the completed audit report
not later than two (2) months after the date such access is first made available
to Tenant. Any discussions between Landlord and Tenant concerning the results of
the audit shall include authorized representatives of each party. If Landlord
agrees with the results of Tenant's completed audit report, or if the parties do
not so agree but a final judgment is reached that payments made by Tenant are in
excess of the payments properly payable to Landlord hereunder, Landlord shall
refund to Tenant the amount of any such excess payments or credit the amount
toward the rent next due from Tenant under this Lease. If Tenant's audit
discloses that payments made by Tenant are less than the payments properly
payable to Landlord hereunder, Tenant shall pay to Landlord the amount of any
such underpayments. If such audit reveals that Landlord's annual statement has
overstated Operating Costs by more than five percent (5%), Landlord shall
reimburse Tenant for the reasonable third-party costs incurred by Tenant's
auditor in conducting the audit. If Tenant fails timely to request an audit or
to provide Landlord with the completed audit report as set forth above, Tenant
shall be deemed to have accepted the Landlord's annual statement for the year
just ended. The rights granted under this Section 3(b)(5) are personal to the
Tenant originally named herein (and any permitted Successor or Affiliate to whom
this Lease is assigned under Section 14.2(c)) and may not be exercised by or on
behalf of any subtenant or other party.

     3.3. Payment of Rent. All amounts payable or reimbursable by Tenant under
          ---------------
this Lease, including late charges and interest (collectively, "Rent"), shall
constitute rent and shall be payable and recoverable as rent in the manner
provided in this Lease. All sums payable to Landlord on demand under the terms
of this Lease shall be payable within thirty (30) days after notice from
Landlord of the amounts due. All rent shall be paid without offset, recoupment
or deduction in lawful money of the United States of America to Landlord at
Landlord's Address for Payment of Rent as set forth in the Basic Lease
Information, or to such other person or at such other place as Landlord may from
time to time designate.

4.   SECURITY DEPOSIT. On execution of this Lease, Tenant shall deposit with
Landlord the amount specified in the Basic Lease Information as the Security
Deposit, if any (the "Security Deposit"), as security for the performance of
Tenant's obligations under this Lease. Landlord may (but shall have no
obligation to) use the Security Deposit or any portion thereof to cure any Event
of Default under this Lease or to compensate Landlord for any damage Landlord
incurs as a result of Tenant's failure to perform any of Tenant's obligations
hereunder. In such event Tenant shall pay to Landlord on demand an amount
sufficient to replenish the Security Deposit. If Tenant is not in default at the
expiration or termination of this Lease, Landlord shall return to Tenant the
Security Deposit or the balance thereof then held by Landlord and not applied as
provided above. Landlord may commingle the Security Deposit with Landlord's
general and other funds. Landlord shall not be required to pay interest on the
Security Deposit to Tenant.

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<PAGE>

5.   USE AND COMPLIANCE WITH LAWS.

     5.1. Use. The Premises shall be used and occupied for general business
          ---
office purposes and for no other use or purpose. Tenant shall comply with all
present and future Laws relating to Tenant's use or occupancy of the Premises
(and make any repairs, alterations or improvements as required to comply with
all such Laws), and shall observe the "Building Rules" (as defined in Section
27 -Rules and Regulations). Tenant shall not do, bring, keep or sell anything in
or about the Premises that is prohibited by, or that will cause a cancellation
of or an increase in the existing premium for, any insurance policy covering the
Property or any part thereof. Tenant shall not permit the Premises to be
occupied or used in any manner that will constitute waste or a nuisance, or
disturb the quiet enjoyment of or otherwise annoy other tenants in the Building.
Without limiting the foregoing, the Premises shall not be used for educational
activities (other than business programs designed for Tenant's employees or
customers), practice of medicine or any of the healing arts, providing social
services, for any governmental use (including embassy or consulate use), or for
personnel agency, customer service office open to the general public, studios
for radio, television or other media, travel agency or reservation center
operations or uses. Tenant shall not, without the prior consent of Landlord, (i)
bring into the Building or the Premises anything that may cause substantial
noise, odor or vibration, overload the floors in the Premises or the Building or
any of the heating, ventilating and air-conditioning ("HVAC"), mechanical,
elevator, plumbing, electrical, fire protection, life safety, security or other
systems in the Building ("Building Systems"), or jeopardize the structural
integrity of the Building or any part thereof; (ii) connect to the utility
systems of the Building any apparatus, machinery or other equipment other than
typical office equipment; or (iii) connect to any electrical circuit in the
Premises any equipment or other load with aggregate electrical power
requirements in excess of 80% of the rated capacity of the circuit.

     5.2. Hazardous Materials.
          -------------------

          (a)  Definitions.
               -----------

               (1)  "Hazardous Materials" shall mean any substance: (A) that now
or in the future is regulated by, or is defined as a hazardous substance,
pollutant or contaminant under, any governmental law, including the
Comprehensive Environmental Response Compensation and Liability Act, 42 U.S.C.
(S) 9601 et seq., and the Resource Conservation and Recovery Act, 42 U.S.C. (S)
         -- ---
6901 et seq., and any oil or hazardous substance or material regulated under the
     -- ---
Massachusetts Hazardous Waste Management Act, as amended, M.G.L. Chapter 21C,
and the Massachusetts Oil and Hazardous Material Release Prevention Act, as
amended, M.G.L. Chapter 21E, and the regulations adopted under these acts, or
(B) that is toxic, dangerous or otherwise hazardous, including gasoline, diesel
fuel, petroleum hydrocarbons, polychlorinated biphenyls (PCBs), asbestos, radon
and urea formaldehyde foam insulation.

               (2)  "Environmental Requirements" shall mean all present and
future Laws, approvals, and other requirements of any kind applicable to
Hazardous Materials.

               (3)  "Handled by Tenant" and "Handling by Tenant" shall mean and
refer to any storage, use, disposal, transportation, or any other activity of
any type by Tenant or its

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<PAGE>

agents, employees, contractors, licensees, assignees, sublessees, transferees or
representatives (collectively, "Representatives") or its guests, customers,
invitees, or visitors (collectively, "Visitors"), at or about the Premises or
Property in connection with or involving Hazardous Materials.

               (4)  "Environmental Losses" shall mean all costs and expenses of
any kind, damages, fines and penalties incurred in connection with any violation
of and compliance with Environmental Requirements and all losses of any kind
attributable to the diminution of value, loss of use or adverse effects on any
portion of the Premises or Property.

               (5)  "Claims" shall mean all claims, actions, losses, damages,
liabilities, costs and expenses of every kind, including reasonable attorneys',
experts' and consultants' fees and costs.

          (b)  Tenant's Covenants. No Hazardous Materials shall be Handled by
               ------------------
Tenant without Landlord's prior written consent, which consent may be withheld
or conditioned in Landlord's absolute discretion. Notwithstanding the foregoing,
normal quantities and use of those Hazardous Materials customarily used in the
conduct of general office activities, such as copier fluids and cleaning
supplies ("Permitted Hazardous Materials"), may be used and stored at the
Premises without Landlord's prior written consent, provided that such activities
of Tenant shall comply at all times with all Environmental Requirements. At the
expiration or termination of the Lease, Tenant shall promptly remove from the
Premises and Property all Hazardous Materials Handled by Tenant. Tenant shall be
responsible and liable for the compliance with all of the provisions of this
Section by all of Tenant's Representatives and Visitors, and all of Tenant's
obligations under this Section (including its indemnification obligations under
subsection (e) below) shall survive the expiration or termination of this Lease.

          (c)  Compliance. Tenant shall at Tenant's expense promptly take all
               ----------
actions required by any governmental agency or entity in connection with or as a
result of the Handling by Tenant of Hazardous Materials. All of the foregoing
work and all Handling by Tenant of all Hazardous Materials shall be performed in
a good, safe and workmanlike manner by consultants qualified and licensed to
undertake such work and in a manner that will not interfere with any other
tenant's quiet enjoyment of the Property or Landlord's use, operation, leasing
and sale of the Property.

          (d)  Landlord's Rights. Landlord shall have the right, but not the
               -----------------
obligation, to enter the Premises at any reasonable time and (except in cases of
emergency) upon reasonable prior notice (i) to confirm Tenant's compliance with
the provisions of this Section 5.2, and (ii) to perform Tenant's obligations
under this Section if Tenant has failed to do so after reasonable notice to
Tenant. Tenant shall pay to Landlord on demand the costs of Landlord's
consultants' fees and all costs incurred by Landlord in performing Tenant's
obligations under this Section.

          (e)  Tenant's Indemnification. Tenant agrees to indemnify, defend,
               ------------------------
protect and hold harmless Landlord and its partners or members and its or their
partners, members, directors, officers, shareholders, employees and agents from
all Environmental Losses and all other Claims incurred at any time and arising
from or in connection with the Handling by Tenant of Hazardous

                                       8
<PAGE>

Materials or Tenant's failure to comply in full with all Environmental
Requirements with respect to the Premises.

     5.3. Landlord represents that, to the best of Landlord's knowledge as of
the date hereof, the Premises do not contain any materials known as of the date
hereof to be Hazardous Materials that materially adversely affect Tenant's use
of the Premises for the permitted uses under Section 5.1.

6.   TENANT IMPROVEMENTS & ALTERATIONS.

     6.1  Landlord and Tenant shall perform their respective obligations with
respect to design and construction of any improvements to be constructed and
installed in the Premises (the "Tenant Improvements"), as provided in the
Construction Rider. Except for any Tenant Improvements to be constructed by
Landlord for Tenant as provided in the Construction Rider, Tenant shall not make
any alterations, improvements or changes to the Premises, including installation
of any security system or telephone or data communication wiring
("Alterations"), without Landlord's prior written consent, which consent shall
not be unreasonably withheld or delayed provided that the proposed Alterations
comply with the provisions of this Section 6 and this Lease. (Notwithstanding
the foregoing, any nonstructural Alterations within the Premises that do not
affect any mechanical, electrical, or other Building systems, do not cost more
than $10,000 in the aggregate, and do not adversely affect the value of the
Premises for general office uses shall not require Landlord's prior approval,
provided that Tenant shall give Landlord notice of the commencement of such work
(including plans and specifications therefor, as provided below) at least ten
(10) days in advance and the work otherwise complies with the provisions of this
Section 6 and this Lease.) Any such Alterations shall be completed by Tenant at
Tenant's sole cost and expense: (i) with due diligence, in a good and
workmanlike manner, using new materials; (ii) in compliance with plans and
specifications approved by Landlord; (iii) in compliance with the non-
discriminatory construction rules and regulations promulgated by Landlord from
time to time; (iv) in accordance with all applicable Laws (including all work,
whether structural or non-structural, inside or outside the Premises, required
to comply fully with all applicable Laws and necessitated by Tenant's work); and
(v) subject to all conditions which Landlord may in Landlord's reasonable
discretion impose. Such conditions may include requirements for Tenant to: (i)
provide payment or performance bonds or additional insurance (from Tenant or
Tenant's contractors, subcontractors or design professionals); (ii) use
contractors or subcontractors designated by Landlord; and (iii) remove all or
part of the Alterations prior to or upon expiration or termination of the Term,
as designated by Landlord. If any work outside the Premises, or any work on or
adjustment to any of the Building Systems, is required in connection with or as
a result of Tenant's work, such work shall be performed at Tenant's expense by
contractors designated by Landlord. Landlord's right to review and approve (or
withhold approval of) Tenant's plans, drawings, specifications, contractor(s)
and other aspects of construction work proposed by Tenant is intended solely to
protect Landlord, the Property and Landlord's interests. No approval or consent
by Landlord shall be deemed or construed to be a representation or warranty by
Landlord as to the adequacy, sufficiency, fitness or suitability thereof or
compliance thereof with applicable Laws or other requirements. Except as
otherwise provided in Landlord's consent, all Alterations shall upon
installation become part of the realty and be the property of Landlord.

                                       9
<PAGE>

     If Tenant specifically requests at the time of its submission of proposed
plans to Landlord by written notice bearing the legend "Request for Confirmation
of Restoration Obligations," Landlord shall identify the elements (if any) of
the proposed Alterations that Landlord may require Tenant to remove at the end
of the Term, provided that Tenant shall not be required to remove Alterations
that are standard for general office use of the Premises and do not increase the
costs of demolishing space for another tenant. Landlord shall have the right to
require Tenant to remove any internal stairs, cafeteria, raised floors, demising
walls for subtenants, vaults, and private bathrooms installed by or for Tenant.

     6.2  Before making any Alterations, Tenant shall submit to Landlord for
Landlord's prior approval reasonably detailed final plans and specifications
prepared by a licensed architect or engineer, a copy of the construction
contract, including the name of the contractor and all subcontractors proposed
by Tenant to make the Alterations and a copy of the contractor's license. Tenant
shall reimburse Landlord upon demand for any expenses reasonably incurred by
Landlord in connection with any Alterations made by Tenant, including reasonable
fees charged by Landlord's contractors or consultants to review plans and
specifications prepared by Tenant and to update the existing as-built plans and
specifications of the Building to reflect the Alterations. Tenant shall obtain
all applicable permits, authorizations and governmental approvals and deliver
copies of the same to Landlord before commencement of any Alterations.

     6.3  Tenant shall keep the Premises and the Property free and clear of
all liens arising out of any work performed, materials furnished or obligations
incurred by Tenant. If any such lien attaches to the Premises or the Property,
and Tenant does not cause the same to be released by payment, bonding or
otherwise within ten (10) business days after the attachment thereof, Landlord
shall have the right but not the obligation to cause the same to be released,
and any sums expended by Landlord (plus Landlord's administrative costs) in
connection therewith shall be payable by Tenant on demand with interest thereon
from the date of expenditure by Landlord at the Interest Rate (as defined in
Section 16.2 - Interest). Tenant shall give Landlord at least ten (10) days'
notice prior to the commencement of any Alterations and cooperate with Landlord
in posting and maintaining notices of non-responsibility in connection
therewith.

     6.4  Subject to the provisions of Section 5 - Use and Compliance with
Laws and the foregoing provisions of this Section, Tenant may install and
maintain furnishings, equipment, movable partitions, business equipment and
other trade fixtures ("Trade Fixtures") in the Premises, provided that the Trade
Fixtures do not become an integral part of the Premises or the Building. Tenant
shall promptly repair any damage to the Premises or the Building caused by any
installation or removal of such Trade Fixtures.

7.   MAINTENANCE AND REPAIRS.

     7.1  By taking possession of the Premises Tenant agrees that the
Premises are then in a good and tenantable condition, subject to completion of
punchlist items under Section 1.2 of Exhibit B. Subject to Section 7.2, during
the Term, Tenant at Tenant's expense but under the direction of Landlord, shall
repair and maintain the Premises, including the interior walls, floor coverings,
ceiling (ceiling tiles and grid), Tenant Improvements, Alterations, fire
extinguishers,

                                      10
<PAGE>

outlets and fixtures, and any appliances (including dishwashers, tenant hot
water heaters and garbage disposers) in the Premises, in a first class
condition, and keep the Premises in a clean, safe and orderly condition.

     7.2  Landlord shall maintain or cause to be maintained in reasonably
good order, condition and repair, the structural portions of the roof,
foundations, floors and exterior walls of the Building, the Building Systems,
and the public and common areas of the Property, such as elevators, stairs,
corridors and restrooms; provided, however, that Tenant shall pay the cost of
repairs for any damage occasioned by Tenant's use of the Premises (with the
exception of reasonable wear and tear) or the Property or any act or omission of
Tenant or Tenant's Representatives or Visitors, to the extent (if any) not
covered by Landlord's property insurance. Landlord shall be under no obligation
to inspect the Premises. Tenant shall promptly report in writing to Landlord any
defective condition known to Tenant which Landlord is required to repair. As a
material part of the consideration for this Lease, Tenant hereby waives any
benefits of any applicable existing or future Law, that allows a tenant to make
repairs at its landlord's expense.

     7.3  Landlord hereby reserves the right, at any time and from time to
time, without liability to Tenant, and without constituting an eviction,
constructive or otherwise, or entitling Tenant to any abatement of rent or to
terminate this Lease or otherwise releasing Tenant from any of Tenant's
obligations under this Lease:

          (a) To make alterations, additions, repairs, improvements to or in or
to decrease the size or area of, all or any part of the Building, the fixtures
and equipment therein, and the Building Systems, provided that (except in cases
of emergency) Landlord shall use reasonable efforts to minimize any disruption
of Tenant's use of the Premises;

          (b) To change the Building's name or street address;

          (c) To install and maintain any and all signs on the exterior and
interior of the Building;

          (d) To reduce, increase, enclose or otherwise change at any time and
from time to time the size, number, location, lay-out and nature of the common
areas (including the Parking Facility, provided that such alterations shall not
reduce the number of parking spaces allotted to tenant under Exhibit E hereto
and provided that (except in cases of emergency) Landlord shall use reasonable
efforts to minimize any disruption of Tenant's use of and access to the
Premises) and other tenancies and premises in the Property and to create
additional rentable areas through use or enclosure of common areas; and

          (e) If any governmental authority promulgates or revises any Law or
imposes mandatory or voluntary controls or guidelines on Landlord or the
Property relating to the use or conservation of energy or utilities or the
reduction of automobile or other emissions or reduction or management of traffic
or parking on the Property (collectively "Controls"), to comply with such
Controls, whether mandatory or voluntary, or make any alterations to the
Property related thereto. In connection with the foregoing, Tenant shall
cooperate with Landlord and abide by all Building regulations that Landlord may,
from time to time, prescribe for the proper functioning and

                                      11
<PAGE>

protection of the heating and air-conditioning systems and in order to maximize
the effect thereof and to conserve heat and air-conditioning.

8.   TENANT'S TAXES. "Tenant's Taxes" shall mean (a) all taxes, assessments,
license fees and other governmental charges or impositions levied or assessed
against or with respect to Tenant's personal property or Trade Fixtures in the
Premises, whether any such imposition is levied directly against Tenant or
levied against Landlord or the Property, (b) all rental, excise, sales or
transaction privilege taxes arising out of this Lease (excluding, however, state
and federal personal or corporate income taxes measured by the income of
Landlord from all sources) imposed by any taxing authority upon Landlord or upon
Landlord's receipt of any rent payable by Tenant pursuant to the terms of this
Lease ("Rental Tax"), and (c) any increase in Taxes attributable to inclusion of
a value placed on Tenant's personal property, Trade Fixtures or Alterations.
Tenant shall pay any Rental Tax to Landlord in addition to and at the same time
as Base Rent is payable under this Lease, and shall pay all other Tenant's Taxes
before delinquency (and, at Landlord's request, shall furnish Landlord
satisfactory evidence thereof). If Landlord pays Tenant's Taxes or any portion
thereof, Tenant shall reimburse Landlord upon demand for the amount of such
payment, together with interest at the Interest Rate from the date of Landlord's
payment to the date of Tenant's reimbursement.

9.   UTILITIES AND SERVICES.

     9.1  Description of Services. Landlord shall furnish to the Premises:
          -----------------------
reasonable amounts of water, heat, ventilation and air-conditioning during the
Business Hours specified in the Basic Lease Information ("Business Hours") on
weekdays except public holidays ("Business Days"); reasonable amounts of
electricity; and janitorial services five days a week (except public holidays),
all in accordance with Exhibit D. Any electrical power supply or supplemental
                       ---------
HVAC required as a result of Tenant's particular use of the Premises (above the
Building standard levels for general office use) shall be installed at Tenant's
expense (subject to the tenant improvement allowance under Exhibit B). Landlord
shall also provide the Building with normal fluorescent tube replacement, window
washing, elevator service, and common area toilet room supplies. Any additional
utilities or services that Landlord may agree to provide (including lamp or tube
replacement for other than Building Standard lighting fixtures) shall be at
Tenant's sole expense.

     9.2  Payment for Additional Utilities and Services.
          ---------------------------------------------

          (a)  Upon request by Tenant in accordance with the procedures
established by Landlord from time to time for furnishing HVAC service at times
other than Business Hours on Business Days, Landlord shall furnish such service
to Tenant and Tenant shall pay for such services on an hourly basis at the then
prevailing rate established for the Building by Landlord. The Building's current
prevailing rate is $47 per hour per floor.

          (b)  If the temperature otherwise maintained in any portion of the
Premises by the HVAC systems of the Building is affected as a result of (i) any
lights, machines or equipment used by Tenant in the Premises, or (ii) the
occupancy of the Premises by more than one person per 150 square feet of
rentable area, then Landlord shall have the right to install any machinery or
equipment reasonably necessary to restore the temperature, including
modifications to the standard

                                      12
<PAGE>

air-conditioning equipment. The cost of any such equipment and modifications,
including the cost of installation and any additional cost of operation and
maintenance of the same, shall be paid by Tenant to Landlord upon demand.

          (c)  Tenant shall pay to Landlord all charges for electricity supplied
to the Premises. Tenant's actual consumption of electricity shall be measured by
any separate meter installed for the Premises or, if the Premises are not
separately metered, based on Landlord's reasonable judgment as to the level of
consumption in the Premises. (The initial Premises hereunder are separately
metered.) Landlord reserves the right to discontinue the furnishing of electric
current to the Premises upon not less than two months' notice (or such longer
time as may be required to make arrangements with the electric utility for
direct service provided Tenant exercises its best efforts to complete said
arrangements as soon as possible), whereupon Tenant's obligation to pay
Additional Rent for electricity under this paragraph shall cease. If Landlord so
elects to discontinue electric service, Tenant shall contract directly with the
utility company supplying electric current.

          (d)  If Tenant's usage of water or any other utility service exceeds
the use of such utility Landlord determines to be typical, normal and customary
for the Building, Landlord may determine the amount of such excess use by any
reasonable means (including the installation at Landlord's request but at
Tenant's expense of a separate meter or other measuring device) and charge
Tenant for the cost of such excess usage. In addition, Landlord may impose a
reasonable charge for the use of any additional or unusual janitorial services
required by Tenant because of any unusual Tenant Improvements or Alterations,
the carelessness of Tenant or the nature of Tenant's business (including hours
of operation).

     9.3  Interruption of Services. In the event of an interruption in, or
          ------------------------
failure or inability to provide any of the services or utilities described in
Section 9.1 - "Description of Services" (a "Service Failure"), Landlord shall
use reasonable and diligent efforts, consistent with a first-class office tower
in downtown Boston, to remedy and limit the duration of any such Service
Failure, provided that such Service Failure shall not, regardless of its
duration, constitute an eviction of Tenant, constructive or otherwise, or impose
upon Landlord any liability whatsoever, including, but not limited to, liability
of consequential damages or loss of business by Tenant or, except as provided
herein, entitle Tenant to an abatement of rent or to terminate this Lease.

          (a)  If any Service Failure not caused by Tenant or its
Representatives prevents Tenant from reasonably using a material portion of the
Premises and Tenant in fact ceases to use such portion of the Premises, Tenant
shall be entitled to an abatement of Base Rent and Additional Rent with respect
to the portion of the Premises that Tenant is prevented from using by reason of
such Service Failure in the following circumstances: (i) if the Service Failure
has persisted and continuously prevented Tenant from using a material portion of
the Premises for a period of five (5) consecutive Business Days after Tenant's
notice to Landlord of such Service Failure and such failure is due to Landlord's
negligence or misconduct or other cause within Landlord's control, the abatement
of rent shall commence on the sixth Business Day following notice of the Service
Failure and continue until Tenant is no longer so prevented from using such
portion of the Premises; and (ii) if the Service Failure has persisted for a
period of ten (10) consecutive Business

                                      13
<PAGE>

Days after Tenant's notice to Landlord of such failure and such failure is due
to causes not within Landlord's control and Tenant in fact does not use such
portion of the Premises for such ten (10) consecutive Business Day period or
more by reason of such Service Failure, then to the extent such Service Failure
is covered by Landlord's rental interruption insurance policy the abatement of
rent shall commence no later than the eleventh Business Day following such
notice of the occurrence of the Service Failure and continue until Tenant is no
longer so prevented from using such portion of the Premises. As used in this
paragraph, "Business Day" shall refer only to full Business Days (from 8:00 A.M.
to 6:00 P.M.) commencing on the Business Day next following the Business Day on
which Tenant delivers to Landlord notice of the Service Failure.

          (b)  If a Service Failure is caused by Tenant or its Representatives,
Landlord shall nonetheless remedy the Service Failure, at the expense of Tenant,
pursuant to Landlord's maintenance and repair obligations under Section 7 -
"Maintenance and Repair" or Section 12.1 - "Landlord's Duty to Repair," as the
case may be, but Tenant shall not be entitled to an abatement of rent or to
terminate this Lease as a result of any such Service Failure.

          (c)  Where the cause of a Service Failure is within the control of a
public utility or other public or quasi-public entity outside Landlord's
control, notification to such utility or entity of the Service Failure and
request to remedy the failure shall constitute "reasonable efforts" by Landlord
to remedy the Service Failure.

          (d)  Tenant hereby waives the provisions of any applicable existing or
future law, ordinance or governmental regulation permitting the termination of
this Lease due to such interruption, failure or inability.

          (e)  This Section does not apply to casualty and/or condemnation, as
to which Sections 12 and 13, respectively, apply.

10.  EXCULPATION AND INDEMNIFICATION.

     10.1 Tenant's Indemnification of Landlord. Tenant shall indemnify, protect,
          ------------------------------------
defend and hold Landlord and Landlord's authorized representatives harmless from
and against Claims arising from (a) the acts or omissions of Tenant or Tenant's
Representatives or Visitors in or about the Property, or (b) any construction or
other work undertaken by Tenant on the Premises (including any design defects),
or (c) any breach or default under this Lease by Tenant, or (d) any loss, injury
or damage, howsoever and by whomsoever caused, to any person or property,
occurring in or about the Premises during the Term, excepting only Claims
described in this clause (d) to the extent they are caused by the willful
misconduct or negligent acts or omissions of Landlord or its authorized
representatives.

     10.2 Damage to Tenant and Tenant's Property. To the maximum extent
          --------------------------------------
permitted by law: (a) Landlord shall not be liable to Tenant for any loss,
injury or other damage to Tenant or to Tenant's property in or about the
Premises or the Property from any cause (including defects in the Property or in
any equipment in the Property; fire, explosion or other casualty; bursting,
rupture, leakage or overflow of any plumbing or other pipes or lines,
sprinklers, tanks, drains, drinking fountains or washstands in, above, or about
the Premises or the Property; or acts of other tenants in

                                      14
<PAGE>

the Property); (b) Tenant hereby waives all claims against Landlord for any such
loss, injury or damage and the cost and expense of defending against claims
relating thereto; and (c) notwithstanding any other provision of this Lease to
the contrary, in no event shall either party be liable to the other for any
punitive or consequential damages or damages for loss of business by the other.

     10.3 Landlord Indemnification. Except as may be provided in Sections 9,
          ------------------------
10.2, 12, and 25, and subject to Section 11.3 and the limitations on the
liability of Landlord set forth in this Lease, Landlord shall indemnify and hold
Tenant harmless from and against any claim arising out of any loss, injury or
damage to any person or property occurring in the common areas of the Building
during the Term, to the extent that such loss, injury, or damage results from
the negligence or willful misconduct of Landlord.

     10.4 Survival.  The obligations of the parties under this Section 10 shall
          --------
survive the expiration or termination of this Lease.

11.  INSURANCE.

     11.1 Tenant's Insurance.
          ------------------

          (a) Liability Insurance. Tenant shall maintain in full force
              -------------------
throughout the Term, commercial general liability insurance providing coverage
on an occurrence form basis with limits of not less than Two Million Dollars
($2,000,000.00) each occurrence for bodily injury and property damage combined,
Two Million Dollars ($2,000,000.00) annual general aggregate, and Two Million
Dollars ($2,000,000.00) products and completed operations annual aggregate.
Tenant's liability insurance policy or policies shall: (i) include premises and
operations liability coverage, products and completed operations liability
coverage, broad form property damage coverage including completed operations,
blanket contractual liability coverage including, to the maximum extent
possible, coverage for the indemnification obligations of Tenant under this
Lease, and personal and advertising injury coverage; (ii) provide that the
insurance company has the duty to defend all insureds under the policy; (iii)
provide that defense costs are paid in addition to and do not deplete any of the
policy limits; (iv) cover liabilities arising out of or incurred in connection
with Tenant's use or occupancy of the Premises or the Property; (v) extend
coverage to cover liability for the actions of Tenant's Representatives and
Visitors; and (vi) designate separate limits for the Property. Each policy of
liability insurance required by this Section shall: (1) contain a cross
liability endorsement or separation of insureds clause; (2) provide that any
waiver of subrogation rights or release prior to a loss does not void coverage;
(3) provide that it is primary to and not contributing with, any policy of
insurance carried by Landlord covering the same loss; (4) provide that any
failure to comply with the reporting provisions by Tenant shall not affect
coverage provided to Landlord, its partners, members, managing members,
managers, affiliates, property managers and Mortgagees; and (5) name Landlord,
its partners, members, managing members, managers, affiliates, the Property
Manager identified in the Basic Lease Information (the "Property Manager"), and
such other parties in interest as Landlord may from time to time reasonably
designate to Tenant in writing, as additional insureds. Such additional insureds
shall be provided at least the same extent of coverage as is provided to Tenant
under such policies with

                                      15
<PAGE>

respect to liability arising out of the ownership, maintenance or use of the
Premises. All endorsements effecting such additional insured status shall be at
least as broad as additional insured endorsement form number CG 20 11 11 85 or
CG 20 11 11 01 96 promulgated by the Insurance Services Office or its successor
organization.

          (b)  Property Insurance. Tenant shall at all times maintain in effect
               ------------------
with respect to any Alterations and Tenant's Trade Fixtures and personal
property, commercial property insurance providing coverage, on an "all risk" or
"special form" basis, in an amount equal to at least the full replacement cost
of the covered property. Tenant may carry such insurance under a blanket policy,
provided that such policy provides coverage equivalent to a separate policy.
During the Term, the proceeds from any such policies of insurance shall be used
for the repair or replacement of the Alterations, Trade Fixtures and personal
property so insured. Landlord shall be provided coverage under such insurance to
the extent of its insurable interest and, if requested by Landlord, both
Landlord and Tenant shall sign all documents reasonably necessary or proper in
connection with the settlement of any claim or loss under such insurance.
Landlord will have no obligation to carry insurance on any Alterations or on
Tenant's Trade Fixtures or personal property.

          (c)  Requirements For All Policies. Each policy of insurance
               -----------------------------
required under this Section 11.1 shall: (i) be in a form, and written by an
insurer, reasonably acceptable to Landlord, (ii) be maintained at Tenant's sole
cost and expense, and (iii) require at least thirty (30) days' written notice to
Landlord prior to any cancellation, nonrenewal or modification of insurance
coverage. Insurance companies issuing such policies shall have rating
classifications of "A" or better and financial size category ratings of "VII" or
better according to the latest edition of the A.M. Best Key Rating Guide. All
insurance companies issuing such policies shall be admitted carriers licensed to
do business in the state where the Property is located. Any deductible amount
under such insurance shall not exceed $5,000. Tenant shall provide to Landlord,
upon request, evidence that the insurance required to be carried by Tenant
pursuant to this Section, including any endorsement effecting the additional
insured status, is in full force and effect and that premiums therefor have been
paid.

          (d)  Updating Coverage. Tenant shall increase the amounts of insurance
               -----------------
as required by any Mortgagee, and, not more frequently than once every three (3)
years, as recommended by Landlord's insurance broker, if, in the opinion of
either of them, the amount of insurance then required under this Lease is not
adequate. Any limits set forth in this Lease on the amount or type of coverage
required by Tenant's insurance shall not limit the liability of Tenant under
this Lease.

          (e)  Certificates of Insurance. Prior to occupancy of the Premises by
               -------------------------
Tenant, and not less than thirty (30) days prior to expiration of any policy
thereafter, Tenant shall furnish to Landlord a certificate of insurance
reflecting that the insurance required by this Section is in force, accompanied
by an endorsement showing the required additional insureds satisfactory to
Landlord in substance and form. Notwithstanding the requirements of this
paragraph, if requested by Landlord's Mortgagee or if reasonably required by
Landlord to confirm Tenant's compliance herewith or to exercise rights as an
additional insured, Tenant shall at Landlord's request provide to

                                      16
<PAGE>

Landlord a certified copy of each insurance policy required to be in force at
any time pursuant to the requirements of this Lease or its Exhibits.

     11.2 Landlord's Insurance. During the Term, to the extent such coverages
          --------------------
are available at a commercially reasonable cost, Landlord shall maintain in
effect insurance on the Building with responsible insurers, on an "all risk" or
"special form" basis, insuring the Building and the Tenant Improvements in an
amount equal to at least 90% of the replacement cost thereof, excluding land,
foundations, footings and underground installations. Landlord may, but shall not
be obligated to, carry insurance against additional perils and/or in greater
amounts.

     11.3 Mutual Waiver of Right of Recovery & Waiver of Subrogation. Landlord
          ----------------------------------------------------------
and Tenant each hereby waive any right of recovery against each other and the
partners, managers, members, shareholders, officers, directors and authorized
representatives of each other for any loss or damage that is covered by any
policy of property insurance maintained by either party (or required by this
Lease to be maintained) with respect to the Premises or the Property or any
operation therein, regardless of cause, including negligence (active or passive)
of the party benefiting from the waiver. If any such policy of insurance
relating to this Lease or to the Premises or the Property does not permit the
foregoing waiver or if the coverage under any such policy would be invalidated
as a result of such waiver, the party maintaining such policy shall obtain from
the insurer under such policy a waiver of all right of recovery by way of
subrogation against either party in connection with any claim, loss or damage
covered by such policy.

12.  DAMAGE OR DESTRUCTION.

     12.1 Landlord's Duty to Repair.
          -------------------------

          (a)  If all or a substantial part of the Premises are rendered
untenantable or inaccessible by damage to all or any part of the Property from
fire or other casualty then, unless either party is entitled to and elects to
terminate this Lease pursuant to Sections 12.2 - Landlord's Right to Terminate
and 12.3 - Tenant's Right to Terminate, Landlord shall, at its expense, use
reasonable efforts to repair and restore the Premises and/or the Property, as
the case may be, to substantially their former condition to the extent permitted
by then applicable Laws; provided, however, that in no event shall Landlord have
any obligation for repair or restoration beyond the extent of insurance proceeds
received by Landlord for such repair or restoration, or for any of Tenant's
personal property, Trade Fixtures or Alterations.

          (b)  If Landlord is required or elects to repair damage to the
Premises and/or the Property, this Lease shall continue in effect, but Tenant's
Base Rent and Additional Rent shall be abated with regard to any portion of the
Premises that Tenant is prevented from using by reason of such damage or its
repair from the date of the casualty until substantial completion of Landlord's
repair of the affected portion of the Premises as required under this Lease. In
no event shall Landlord be liable to Tenant by reason of any injury to or
interference with Tenant's business or property arising from fire or other
casualty or by reason of any repairs to any part of the Property necessitated by
such casualty.

                                      17
<PAGE>

     12.2 Landlord's Right to Terminate.  Landlord may elect to terminate this
          -----------------------------
Lease following damage by fire or other casualty under the following
circumstances :

          (a)  If, in the reasonable judgment of Landlord, the Premises and the
Property cannot be substantially repaired and restored under applicable Laws
within one (1) year from the date of the casualty;

          (b)  If, in the reasonable judgment of Landlord, adequate proceeds are
not, for any reason, made available to Landlord from Landlord's insurance
policies (and/or from Landlord's funds made available for such purpose, at
Landlord's sole option) to make the required repairs;

          (c)  If the Building is damaged or destroyed to the extent that, in
the reasonable judgment of Landlord, the cost to repair and restore the Building
would exceed twenty-five percent (25%) of the full replacement cost of the
Building, whether or not the Premises are at all damaged or destroyed; or

          (d)  If the fire or other casualty occurs during the last year of the
Term.

If any of the circumstances described in subsections (a), (b), (c) or (d) of
this Section 12.2 occur or arise, Landlord shall give Tenant notice within one
hundred and twenty (120) days after the date of the casualty, specifying whether
Landlord elects to terminate this Lease as provided above and, if not,
Landlord's estimate of the time required to complete Landlord's repair
obligations under this Lease.

     12.3 Tenant's Right to Terminate. If all or a substantial part of the
          ---------------------------
Premises are rendered untenantable or inaccessible by damage to all or any part
of the Property from fire or other casualty, and Landlord does not elect to
terminate as provided above, then Tenant may elect to terminate this Lease if
Landlord's estimate of the time required to complete Landlord's repair
obligations under this Lease is greater than nine (9) months, in which event
Tenant may elect to terminate this Lease by giving Landlord notice of such
election to terminate within thirty (30) days after Landlord's notice to Tenant
pursuant to Section 12.2 - Landlord's Right to Terminate.

     12.4 Waiver. Landlord and Tenant each hereby waive the provisions of any
          ------
applicable existing or future Law permitting the termination of a lease
agreement in the event of damage or destruction under any circumstances other
than as provided in Sections 12.2 - Landlord's Right to Terminate and 12.3 -
Tenant's Right to Terminate.

13.  CONDEMNATION.

     13.1 Definitions.
          -----------

          (a)  "Award" shall mean all compensation, sums, or anything of value
awarded, paid or received on a total or partial Condemnation.

          (b)  "Condemnation" shall mean (i) a permanent taking (or a temporary
taking for a period extending beyond the end of the Term) pursuant to the
exercise of the power of

                                      18
<PAGE>

condemnation or eminent domain by any public or quasi-public authority, private
corporation or individual having such power ("Condemnor"), whether by legal
proceedings or otherwise, or (ii) a voluntary sale or transfer by Landlord to
any such authority, either under threat of condemnation or while legal
proceedings for condemnation are pending.

          (c)  "Date of Condemnation" shall mean the earlier of the date that
title to the property taken is vested in the Condemnor or the date the Condemnor
has the right to possession of the property being condemned.

     13.2 Effect on Lease.
          ---------------

          (a)  If the Premises are totally taken by Condemnation, this Lease
shall terminate as of the Date of Condemnation. If a portion but not all of the
Premises is taken by Condemnation, this Lease shall remain in effect; provided,
however, that if the portion of the Premises remaining after the Condemnation
will be unsuitable for Tenant's continued use, then upon notice to Landlord
within thirty (30) days after Landlord notifies Tenant of the Condemnation,
Tenant may terminate this Lease effective as of the Date of Condemnation.

          (b)  If twenty-five percent (25%) or more of the Project or of the
parcel(s) of land on which the Building is situated or of the Parking Facility
or of the floor area in the Building is taken by Condemnation, or if as a result
of any Condemnation the Building is no longer reasonably suitable for use as an
office building, whether or not any portion of the Premises is taken, Landlord
may elect to terminate this Lease, effective as of the Date of Condemnation, by
notice to Tenant within thirty (30) days after the Date of Condemnation,
provided that Landlord terminates the leases for all other similarly situated
tenants in the Building.

          (c)  If all or a portion of the Premises is temporarily taken by a
Condemnor for a period not extending beyond the end of the Term, this Lease
shall remain in full force and effect.

     13.3 Restoration. If this Lease is not terminated as provided in Section
          -----------
13.2 - Effect on Lease, Landlord, at its expense, shall diligently proceed to
repair and restore the Premises to substantially its former condition (to the
extent permitted by then applicable Laws) and/or repair and restore the Building
to an architecturally complete office building; provided, however, that
Landlord's obligations to so repair and restore shall be limited to the amount
of any Award received by Landlord and not required to be paid to any Mortgagee
(as defined in Section 20.2 below). In no event shall Landlord have any
obligation to repair or replace any improvements in the Premises beyond the
amount of any Award received by Landlord for such repair or to repair or replace
any of Tenant's personal property, Trade Fixtures, or Alterations.

     13.4 Abatement and Reduction of Rent. If any portion of the Premises is
          -------------------------------
taken in a Condemnation or is rendered permanently untenantable by repairs
necessitated by the Condemnation, and this Lease is not terminated, the Base
Rent and Additional Rent payable under this Lease shall be proportionally
reduced as of the Date of Condemnation based upon the percentage of rentable
square feet in the Premises so taken or rendered permanently untenantable. In
addition, if this Lease remains in effect following a Condemnation and Landlord
proceeds to repair and restore the Premises, the Base Rent and Additional Rent
payable under this Lease shall

                                      19
<PAGE>

be abated during the period of such repair or restoration to the extent such
repairs prevent Tenant's use of the Premises.

     13.5 Awards. Any Award made shall be paid to Landlord, and Tenant
          ------
hereby assigns to Landlord, and waives all interest in or claim to, any such
Award, including any claim for the value of the unexpired Term; provided,
however, that Tenant shall be entitled to receive, or to prosecute a separate
claim for, an Award for a temporary taking of the Premises or a portion thereof
by a Condemnor where this Lease is not terminated (to the extent such Award
relates to the unexpired Term), or an Award or portion thereof separately
designated for relocation expenses or the interruption of or damage to Tenant's
business or as compensation for Tenant's personal property, Trade Fixtures or
Alterations.

     13.6 Waiver. Landlord and Tenant each hereby waive the provisions of any
          ------
applicable existing or future Law allowing either party to petition for a
termination of this Lease upon a partial taking of the Premises and/or the
Property.

14.  ASSIGNMENT AND SUBLETTING.

     14.1 Landlord's Consent Required. Tenant shall not assign this Lease or
          ---------------------------
any interest therein, or sublet or license or permit the use or occupancy of the
Premises or any part thereof by or for the benefit of anyone other than Tenant,
or in any other manner transfer all or any part of Tenant's interest under this
Lease (each and all a "Transfer"), without the prior written consent of Landlord
as set forth in this Article 14. If Tenant is a business entity, any direct or
indirect transfer of fifty percent (50%) or more of the ownership interest of
the entity (whether in a single transaction or in the aggregate through more
than one transaction) shall be deemed a Transfer. Notwithstanding any provision
in this Lease to the contrary, Tenant shall not mortgage, pledge, hypothecate or
otherwise encumber this Lease or all or any part of Tenant's interest under this
Lease.

     14.2 Landlord's Consent.
          ------------------

          (a)  Prior to any proposed Transfer, Tenant shall submit in writing to
Landlord (i) the name and legal composition of the proposed assignee, subtenant,
user or other transferee (each a "Proposed Transferee"); (ii) the nature of the
business proposed to be carried on in the Premises; (iii) a current balance
sheet, income statements for the last two years and such other financial and
other information concerning the Proposed Transferee as Landlord may require;
and (iv) a copy of a term sheet or letter of intent with the economic terms of
the proposed transaction, or the proposed assignment, sublease or other
agreement governing the proposed Transfer. Within fifteen (15) Business Days
after Landlord receives all such information it shall notify Tenant whether it
approves or disapproves such Transfer or if it elects to proceed under Section
14.7 - Landlord's Right to Space. If Landlord approves the terms of the proposed
Transfer submitted to Landlord and does not exercise its recapture right under
Section 14.7, within ninety (90) days after such approval Tenant shall submit to
Landlord a fully executed agreement on the terms set forth in Tenant's original
submission to Landlord. If Tenant's original submission was a letter of intent,
the final form of the proposed Transfer agreement shall be subject to Landlord's
reasonable approval. If Tenant does not submit such agreement to Landlord within
such ninety-

                                      20
<PAGE>

day (90) period, or if Tenant desires to modify the terms of the proposed
Transfer from those set forth in Tenant's original submission, Tenant shall
recommence the process under this Section 14.2(a) prior to entering into any
Transfer agreement.

          (b)  Landlord's consent to a proposed sublease or license shall,
subject to the other provisions of this Article 14, not be unreasonably
withheld. Tenant acknowledges and agrees that, among other circumstances for
which Landlord could reasonably withhold consent to a proposed Transfer, it
shall be reasonable for Landlord to withhold consent where (i) the Proposed
Transferee does not intend itself to occupy the entire portion of the Premises
assigned or sublet, (ii) Landlord reasonably disapproves of the Proposed
Transferee's business operating ability or history, reputation or
creditworthiness or the character of the business to be conducted by the
Proposed Transferee at the Premises, (iii) the Proposed Transferee is a
governmental agency or unit or an existing tenant in the Project, (iv) the
proposed Transfer would violate any "exclusive" rights of any tenants in the
Project, (v) Landlord or Landlord's agent has shown space in the Building to the
Proposed Transferee or responded to any inquiries from the Proposed Transferee
or the Proposed Transferee's agent concerning availability of space in the
Building, at any time within the preceding nine months, or (vi) Landlord
otherwise reasonably determines that the proposed Transfer would have the effect
of decreasing the value of the Building or increasing the expenses associated
with operating, maintaining and repairing the Property. Except for permitted
assignments under Section 14.2(c), Landlord may withhold its consent to a
proposed assignment of the Lease in its sole discretion. In no event may Tenant
publicly offer or advertise all or any portion of the Premises for assignment or
sublease at a rental less than that then sought by Landlord for a direct lease
(non-sublease) of comparable space in the Project.

          (c)  Notwithstanding anything to the contrary in this Article
14, the following transactions shall not require the consent of Landlord
provided that (i) Landlord shall receive prior notice thereof plus reasonable
evidence upon closing that the transaction is in fact one of the following, (ii)
the proposed Transfer complies with all other provisions of this Lease,
including, without limitation, this Article 14, does not alter Landlord's rights
under the Lease, and does not impose any additional obligation on Landlord; and
(iii) in the case of an assignment under this Section 14(c) the assignee shall
have a net worth at least equal to the greater of the net worth of the Tenant as
of the date hereof or as of the day immediately preceding such assignment:

          (1)  An assignment of the Lease to an entity succeeding to the
business and assets of Tenant, whether by way of merger, consolidation or
otherwise ("Successor");

          (2)  A sublease or assignment of the Lease to an entity that directly
or indirectly controls, is controlled by, or is under common control with Tenant
("Affiliate"). For purposes of this clause (2), control shall mean possession of
more than fifty percent (50%) of the shares or other beneficial ownership
interests of the entity in question together with the power to control and
manage the affairs thereof either directly or by election of directors and/or
officers.

     14.3 Excess Consideration. If Landlord consents to the Transfer and if the
          --------------------
consideration paid by any transferee (the "Transferee") for the Transfer,
including, in the case of a sublease, the

                                      21
<PAGE>

rent and other consideration payable by the subtenant exceeds (a) the amount of
Base Rent and Additional Rent payable hereunder applicable to the subleased
space in question, and (b) all costs reasonably incurred by Tenant in connection
with such sublease or assignment, then Tenant shall pay fifty percent (50%) of
such excess to Landlord as additional rent, within ten (10) days after receipt
by Tenant.

     14.4 No Release Of Tenant. No consent by Landlord to any Transfer, nor
          --------------------
any Transfer whether or not permitted under this Article 14, shall relieve
Tenant of any obligation to be performed by Tenant under this Lease, whether
occurring before or after such consent, assignment, subletting or other
Transfer. Each Transferee shall be jointly and severally liable with Tenant (and
Tenant shall be jointly and severally liable with each Transferee) for the
payment of rent (or, in the case of a sublease, rent in the amount set forth in
the sublease) and for the performance of all other terms and provisions of this
Lease and Landlord, at Landlord's option, may collect such rent directly from
such Transferee without releasing Tenant from Tenant's obligations. The consent
by Landlord to any Transfer shall not relieve Tenant or any such Transferee from
the obligation to obtain Landlord's express prior written consent to any
subsequent Transfer by Tenant or any Transferee. The acceptance of rent by
Landlord from any other person (whether or not such person is an occupant of the
Premises) shall not be deemed to be a waiver by Landlord of any provision of
this Lease or to be a consent to any Transfer.

     14.5 Expenses and Attorneys' Fees. Tenant shall pay to Landlord on demand
          ----------------------------
all reasonable costs and expenses (including reasonable attorneys' fees)
incurred by Landlord in connection with reviewing or consenting to any proposed
Transfer (including any request for consent to, or any waiver of Landlord's
rights in connection with, any security interest in any of Tenant's property at
the Premises).

     14.6 Effectiveness of Transfer. Prior to the date on which any permitted
          -------------------------
Transfer (whether or not requiring Landlord's consent) becomes effective, Tenant
shall deliver to Landlord a counterpart of the fully executed Transfer document
and Landlord's standard form of Consent to Assignment or Consent to Sublease
executed by Tenant and the Transferee in which each of Tenant and the Transferee
confirms its obligations pursuant to this Lease. Failure or refusal of a
Transferee to execute any such instrument shall not release or discharge the
Transferee from liability as provided herein. The voluntary, involuntary or
other surrender of this Lease by Tenant, or a mutual cancellation by Landlord
and Tenant, shall not work a merger, and any such surrender or cancellation
shall, at the option of Landlord, either terminate all or any existing subleases
or operate as an assignment to Landlord of any or all of such subleases.

     14.7 Landlord's Right to Space. Notwithstanding any of the above
          -------------------------
provisions of this Section to the contrary, if Tenant notifies Landlord that it
desires to enter into a Transfer, Landlord, in lieu of consenting to such
Transfer, may elect, within the time period set forth in Section 14(a) for such
election, (x) in the case of an assignment or a sublease of the entire Premises,
to terminate this Lease, or (y) in the case of a sublease of less than the
entire Premises, to terminate this Lease as it relates to the space proposed to
be subleased by Tenant. In such event, this Lease will terminate (or the space
proposed to be subleased will be removed from the Premises subject to this Lease
and the Base Rent and Tenant's Share under this Lease shall be proportionately
reduced) on the later

                                      22
<PAGE>

of: (i) 60 days after the date of Landlord's notice to Tenant making the
election set forth in this Section 14.7 or (ii) the date that the Transfer was
proposed to be effective, and Landlord may lease such space to any party,
including the prospective Transferee identified by Tenant.

     14.8 Assignment of Sublease Rents. Tenant hereby absolutely and irrevocably
          ----------------------------
assigns to Landlord any and all rights to receive rent and other consideration
from any sublease and agrees that Landlord, as assignee or as attorney-in-fact
for Tenant for purposes hereof, or a receiver for Tenant appointed on Landlord's
application may (but shall not be obligated to) collect such rents and other
consideration and apply the same toward Tenant's obligations to Landlord under
this Lease; provided, however, that Landlord grants to Tenant at all times prior
to occurrence of any breach or default by Tenant a revocable license to collect
such rents (which license shall automatically and without notice be and be
deemed to have been revoked and terminated immediately upon any Event of
Default).

15.  DEFAULT AND REMEDIES.

     15.1 Events of Default.  The occurrence of any of the following shall
          -----------------
constitute an "Event of Default" by Tenant:

          (a)  Tenant fails to make any payment of rent when due, or any amount
required to replenish the security deposit as provided in Section 4 above,
provided that, for the first two (2) times during any twelve (12) month period
that such a payment or amount is due and owing, Landlord shall provide written
notice to Tenant of such overdue amounts and an Event of Default shall only
occur if payment in full is not received by Landlord within five (5) days after
such written notice to Tenant. If such a payment or amount is due and owing more
than once during any twelve (12) month period, then, in such instance, Landlord
shall not be required to provide written notice to Tenant of such overdue
payment or amount and Tenant's failure to pay same shall constitute an immediate
Event of Default without further notice from Landlord.

          (b)  Tenant abandons the Premises.

          (c)  Tenant fails timely to deliver any subordination document,
estoppel certificate or financial statement requested by Landlord within the
applicable time period specified in Sections 20 - Encumbrances - and 21 -
Estoppel Certificates and Financial Statements - below.

          (d)  Tenant violates the restrictions on Transfer set forth in Section
14 - Assignment and Subletting.

          (e)  Tenant ceases doing business as a going concern; makes an
assignment for the benefit of creditors; is adjudicated an insolvent, files a
petition (or files an answer admitting the material allegations of a petition)
seeking relief under any state or federal bankruptcy or other statute, law or
regulation affecting creditors' rights; all or substantially all of Tenant's
assets are subject to judicial seizure or attachment and are not released within
30 days, or Tenant consents to or acquiesces in the appointment of a trustee,
receiver or liquidator for Tenant or for all or any substantial part of Tenant's
assets.

                                      23
<PAGE>

          (f) Tenant fails, within ninety (90) days after the commencement of
any proceedings against Tenant seeking relief under any state or federal
bankruptcy or other statute, law or regulation affecting creditors' rights, to
have such proceedings dismissed, or Tenant fails, within ninety (90) days after
an appointment, without Tenant's consent or acquiescence, of any trustee,
receiver or liquidator for Tenant or for all or any substantial part of Tenant's
assets, to have such appointment vacated.

          (g) Tenant fails to perform or comply with any provision of this Lease
other than those described in (a) through (f) above, and does not fully cure
such failure within thirty (30) days after notice to Tenant or, if such failure
cannot be cured within such thirty (30)-day period, Tenant fails within such
thirty (30)-day period to commence, and thereafter diligently proceed with, all
actions necessary to cure such failure as soon as reasonably possible but in all
events within ninety (90) days of such notice; provided, however, that if
Landlord in Landlord's reasonable judgment determines that such failure cannot
or will not be cured by Tenant within such ninety (90) days, then such failure
shall constitute an Event of Default immediately upon such notice to Tenant.

     15.2 Remedies. Upon the occurrence of an Event of Default, Landlord shall
          --------
have the following remedies, which shall not be exclusive but shall be
cumulative and shall be in addition to any other remedies now or hereafter
allowed by law:

          (a) Landlord may terminate this Lease at any time by written notice to
Tenant or by any other means available under law. Upon such termination,
Landlord shall be entitled, in accordance with the provisions of applicable law,
immediately to recover possession of the Premises from Tenant and those claiming
under Tenant. Tenant expressly acknowledges that in the absence of such written
notice from Landlord, no other act of Landlord, including re-entry into the
Premises, efforts to relet the Premises, reletting of the Premises for Tenant's
account, storage of Tenant's personal property and Trade Fixtures, acceptance of
keys to the Premises from Tenant or exercise of any other rights and remedies
under this Section, shall constitute an acceptance of Tenant's surrender of the
Premises or constitute a termination of this Lease or of Tenant's right to
possession of the Premises. Upon such termination in writing of this Lease, as
herein provided, this Lease shall terminate and Landlord shall be entitled to
recover damages from Tenant as provided herein and under any other applicable
existing or future Law providing for recovery of damages for such breach. In the
case of termination of this Lease pursuant to this Section, Tenant shall
reimburse Landlord for all expenses arising out of such termination, including
without limitation, all costs incurred in collecting amounts due from Tenant
under this Lease (including reasonable attorneys' fees, costs of litigation and
the like); all expenses incurred by Landlord in attempting to relet the Premises
or parts thereof (including advertisements, brokerage commissions, Tenant's
allowances, costs of preparing space, and the like); and all of Landlord's other
reasonable expenditures necessitated by the termination. The reimbursement from
Tenant shall be due and payable immediately from time to time upon notice from
Landlord that an expense has been incurred, without regard to whether the
expense was incurred before or after the termination.

          (b) Landlord may elect by written notice to Tenant within one year
following such termination to be indemnified for loss of rent by a lump sum
payment representing the then present value of the amount of rent and additional
charges that would have been paid in accordance

                                      24
<PAGE>

with this Lease for the remainder of the Term minus the then present value of
the aggregate fair market rent and additional charges payable for the Premises
for the remainder of the Term (if less than the rent and additional charges
payable hereunder), estimated as of the date of the termination, and taking into
account reasonable projections of vacancy and time required to re-lease the
Premises. (For the purposes of calculating the rent which would have been paid
hereunder for the lump sum payment calculation described herein, the last full
year's Additional Rent is to be deemed constant for each year thereafter. The
Federal Reserve discount rate (or equivalent) shall be used in calculating
present values.) Should the parties be unable to agree on a fair market rent,
the matter shall be submitted, upon the demand of either party, to the Boston,
Massachusetts office of the American Arbitration Association, with a request for
arbitration in accordance with the rules of the Association by a single
arbitrator who shall be a licensed real estate broker with at least ten years
experience as an appraiser of major office buildings in downtown Boston. The
parties agree that a decision of the arbitrator shall be conclusive and binding
upon them. If, at the end of the Term, the rent which Landlord has actually
received from the Premises is less than the aggregate fair market rent estimated
as aforesaid, Tenant shall thereupon pay Landlord the amount of such difference.
If Landlord does not make the election provided for in this Section, Tenant
shall indemnify Landlord for the loss of rent by a payment at the end of each
month which would have been included in the Term, representing the difference
between the rent which would have been paid in accordance with this Lease (Base
Rent and Additional Rent) and the rent actually derived from the Premises by
Landlord for such month (the amount of rent deemed derived shall be the actual
amount less any portion thereof attributable to Landlord's reletting expenses
that have not been reimbursed by Tenant thereunder).

     In lieu of any other damages or indemnity and in lieu of full recovery by
Landlord of all sums payable under all of the foregoing provisions of this
Section, Landlord may by written notice to Tenant within 6 months after
termination under any of the provisions contained in this Lease and before such
full recovery, elect to recover, and Tenant shall thereupon pay, as liquidated
damages, an amount equal to the lesser of (i) the aggregate of Base Rent and
Additional Rent for the balance of the Term had it not been terminated or (ii)
the aggregate thereof for the 12 months ending one year after the termination
date, plus in either case (iii) the amount of Base Rent and Additional Rent of
any kind accrued and unpaid at the time of termination and minus (iv) the amount
of any recovery by Landlord under the foregoing provisions of this Section
15.2(b) up to the time of payment of such liquidated damages (but reduced by any
amounts of reimbursement of reletting expenses). Liquidated damages hereunder
shall not be in lieu of any claims for reimbursement of reletting expenses.

          (c) Any obligation imposed by law upon Landlord to relet the Premises
shall be subject to the reasonable requirements of Landlord to lease to high
quality tenants and to develop the Building in a harmonious manner with an
appropriate mix of uses, tenants, floor areas and terms of tenancies, and the
like. Landlord's actual damages hereunder shall be subject to mitigation by the
amount of the damages that Tenant proves would have been avoided by Landlord in
the exercise of commercially reasonable efforts to relet the Premises; provided
that such reasonable efforts shall not require Landlord (i) to solicit or
negotiate with prospective new tenants until Landlord obtains full and complete
possession of the Premises, free of any claim by Tenant or its successors, (ii)
to relet the Premises prior to leasing any other space in the Project

                                      25
<PAGE>

then available or scheduled to become available, (iii) to relet the Premises in
a manner inconsistent with Landlord's leasing requirements under the preceding
sentence or inconsistent with the criteria for Landlord's approval of proposed
assignees or subtenants under Section 14, (iv) to expend any amounts on tenant
improvements or other leasing costs in excess of the levels in Landlord's budget
or leasing guidelines for the Project, or (v) to relet the Premises for a rental
less than the current fair market rental then prevailing for similar office
space in the Project. Tenant's liability hereunder shall not be diminished or
reduced if, or to the extent, that such reasonable efforts of Landlord to relet
the Premises are unsuccessful.

          (d) Any termination of this Lease and repossession of the Premises
under this Section shall be without prejudice to any remedies which Landlord
might otherwise have for arrears of rent or for a prior breach of the provisions
of this Lease. Tenant waives any statutory notice to quit and equitable rights
in the nature of further cure or redemption, and Tenant agrees that upon
Landlord's termination of this Lease Landlord shall be entitled to re-entry and
possession in accordance with the terms hereof. Tenant agrees that a notice by
Landlord alleging any default shall, at Landlord's option (the exercise of such
option shall be indicated by the inclusion of the words "notice to quit" in such
notice), constitute a statutory notice to quit. If Landlord exercises its option
to designate a notice of default hereunder as a statutory notice to quit, any
grace periods provided for herein shall run concurrently with any statutory
notice periods. Landlord and Tenant waive trial by jury in any action to which
they are parties. Tenant further agrees that it shall not interpose any
counterclaim or set-off in any summary proceeding or in any action based in
whole or in part on non-payment of rent unless Tenant has no right to commence
an independent proceeding to seek to recover on account of such claim.

          (e) Landlord may cure the Event of Default at Tenant's expense. If
Landlord pays any sum or incurs any expense in curing the Event of Default,
Tenant shall reimburse Landlord upon demand for the amount of such payment or
expense with interest at the Interest Rate from the date the sum is paid or the
expense is incurred until Landlord is reimbursed by Tenant.

          (f) After any termination of this Lease and repossession of the
Premises under this Section, Landlord may, without notice, store Tenant's
personal property (and those of any person claiming under Tenant) at the expense
and risk of Tenant or, if Landlord so elects, Landlord may sell such personal
property at public auction or auctions or at private sale or sales after seven
days notice to Tenant and apply the net proceeds to the earliest of installments
of rent or other charges owing Landlord.

16.  LATE CHARGE AND INTEREST.

     16.1 Late Charge. If any payment of rent is not received by Landlord when
          -----------
due on more than one occasion in any twelve-month period, Tenant shall pay to
Landlord on demand as a late charge an additional amount equal to four percent
(4%) of the overdue payment. A late charge shall not be imposed more than once
on any particular installment not paid when due, but imposition of a late charge
on any payment not made when due does not eliminate or supersede late charges
imposed on other (prior) payments not made when due or preclude imposition of a
late charge on other installments or payments not made when due.

                                      26
<PAGE>

     16.2 Interest. In addition to the late charges referred to above, which are
          --------
intended to defray Landlord's costs resulting from late payments, any payment
from Tenant to Landlord not paid when due shall at Landlord's option bear
interest from the date due until paid to Landlord by Tenant at the rate of
twelve percent (12%) per annum or the maximum lawful rate that Landlord may
charge to Tenant under applicable laws, whichever is less (the "Interest Rate").
Acceptance of any late charge and/or interest shall not constitute a waiver of
Tenant's default with respect to the overdue sum or prevent Landlord from
exercising any of its other rights and remedies under this Lease.

17.  WAIVER. No provisions of this Lease shall be deemed waived by Landlord
unless such waiver is in a writing signed by Landlord. The waiver by Landlord of
any breach of any provision of this Lease shall not be deemed a waiver of such
provision or of any subsequent breach of the same or any other provision of this
Lease. No delay or omission in the exercise of any right or remedy of Landlord
upon any default by Tenant shall impair such right or remedy or be construed as
a waiver. Landlord's acceptance of any payments of rent due under this Lease
shall not be deemed a waiver of any default by Tenant under this Lease
(including Tenant's recurrent failure to timely pay rent) other than Tenant's
nonpayment of the accepted sums, and no endorsement or statement on any check or
payment or in any letter or document accompanying any check or payment shall be
deemed an accord and satisfaction. Landlord's consent to or approval of any act
by Tenant requiring Landlord's consent or approval shall not be deemed to waive
or render unnecessary Landlord's consent to or approval of any subsequent act by
Tenant.

18.  ENTRY, INSPECTION AND CLOSURE. Upon reasonable oral or written notice to
Tenant (and without notice in emergencies), Landlord and its authorized
representatives may enter the Premises at all reasonable times to: (a) determine
whether the Premises are in good condition, (b) determine whether Tenant is
complying with its obligations under this Lease, (c) perform any maintenance or
repair of the Premises or the Building that Landlord has the right or obligation
to perform, (d) install or repair improvements for other tenants where access to
the Premises is required for such installation or repair, (e) serve, post or
keep posted any notices required or allowed under the provisions of this Lease,
(f) show the Premises to prospective brokers, agents, buyers, transferees,
Mortgagees or tenants, or (g) do any other act or thing necessary for the safety
or preservation of the Premises or the Building. When reasonably necessary
Landlord may temporarily close entrances, doors, corridors, elevators or other
facilities in the Building without liability to Tenant by reason of such
closure. Landlord shall conduct its activities under this Section in a manner
that will minimize inconvenience to Tenant (and Tenant's access to the Premises)
without incurring additional expense to Landlord. In no event shall Tenant be
entitled to an abatement of rent on account of any entry by Landlord, and
Landlord shall not be liable in any manner for any inconvenience, loss of
business or other damage to Tenant or other persons arising out of Landlord's
entry on the Premises in accordance with this Section. No action by Landlord
pursuant to this paragraph shall constitute an eviction of Tenant, constructive
or otherwise, entitle Tenant to an abatement of rent or to terminate this Lease
or otherwise release Tenant from any of Tenant's obligations under this Lease.

                                      27
<PAGE>

19.  SURRENDER AND HOLDING OVER.

     19.1 Surrender. Upon the expiration or termination of this Lease, Tenant
          ---------
shall surrender the Premises and all Tenant Improvements and Alterations to
Landlord broom-clean and in their original condition, except for reasonable wear
and tear, damage from casualty or condemnation and any changes resulting from
approved Alterations; provided, however, that prior to the expiration or
termination of this Lease (a) if Landlord removes the telephone and other
cabling installed in the Premises by the prior tenant, Tenant shall remove all
telephone and other cabling installed in the Building by Tenant, (b) Tenant
shall remove from the Premises all of Tenant's personal property and Trade
Fixtures and all Alterations that Landlord has elected to require Tenant to
remove as provided in Section 6.1 - Tenant Improvements & Alterations, and (c)
Tenant shall repair any damage caused by such removal of the items in clauses
(a) and (b). If such removal is not completed before the expiration or
termination of the Term, Landlord shall have the right (but no obligation) to
remove the same, and Tenant shall pay Landlord on demand for all costs of
removal and storage thereof and for the rental value of the Premises for the
period from the end of the Term through the end of the time reasonably required
for such removal. Landlord shall also have the right to retain or dispose of all
or any portion of such property if Tenant does not pay all such costs and
retrieve the property within ten (10) days after notice from Landlord (in which
event title to all such property described in Landlord's notice shall be
transferred to and vest in Landlord). Tenant waives all Claims against Landlord
for any damage or loss to Tenant resulting from Landlord's removal, storage,
retention, or disposition of any such property. Upon expiration or termination
of this Lease or of Tenant's possession, whichever is earliest, Tenant shall
surrender all keys to the Premises or any other part of the Building and shall
deliver to Landlord all keys for or make known to Landlord the combination of
locks on all safes, cabinets and vaults that may be located in the Premises.
Tenant's obligations under this Section shall survive the expiration or
termination of this Lease.

     19.2 Holding Over. If Tenant (directly or through any Transferee or other
          ------------
successor-in-interest of Tenant) remains in possession of the Premises after the
expiration or termination of this Lease, Tenant's continued possession shall be
on the basis of a tenancy at will or tenant by the month. No act or omission by
Landlord, other than its specific written consent, shall constitute permission
for Tenant to continue in possession of the Premises, and if such consent is
given or declared to have been given by a court judgment, Landlord may terminate
such holdover tenancy at any time upon thirty (30) days written notice. In the
event of any such holdover, Tenant shall continue to comply with or perform all
the terms and obligations of Tenant under this Lease, except that the monthly
Base Rent during Tenant's holding over shall be, for the first 30 days of such
holdover, at 150% of the Base Rent payable in the last full month prior to the
termination thereof and, thereafter, at twice the Base Rent payable in the last
full month prior to the termination hereof. Acceptance by Landlord of rent after
such termination shall not constitute a renewal or extension of this Lease; and
nothing contained in this provision shall be deemed to waive Landlord's right of
re-entry or any other right hereunder or at law. Notwithstanding the foregoing,
if Landlord desires to regain possession of the Premises promptly after the
termination or expiration hereof and prior to acceptance of rent for any period
thereafter, Landlord may, at its option, forthwith re-enter and take possession
of the Premises or any part thereof without process or if required with any
process required under applicable Laws. Tenant shall indemnify, defend and hold
Landlord harmless from

                                      28
<PAGE>

and against all Claims arising or resulting from Tenant's failure to timely
surrender the Premises, including (i) any loss, cost, or damages incurred by any
prospective tenant of the Premises, and (ii) Landlord's damages as a result of
such prospective tenant rescinding or refusing to enter into the prospective
lease of the Premises by reason of such failure to timely surrender the
Premises.

20.  ENCUMBRANCES.

     20.1 Subordination. This Lease is expressly made subject and subordinate to
          -------------
any mortgage, deed of trust, ground lease, underlying lease or like encumbrance
affecting any part of the Property or any interest of Landlord therein
("Encumbrance") which is now existing or hereafter executed or recorded;
provided, however, that such subordination shall only be effective, as to future
Encumbrances, if the holder of the Encumbrance agrees that this Lease shall
survive the termination of the Encumbrance by lapse of time, foreclosure or
otherwise so long as Tenant is not in default under this Lease. Provided the
conditions of the preceding sentence are satisfied, Tenant shall execute and
deliver to Landlord, within ten (10) days after written request therefor by
Landlord and in a form reasonably requested by Landlord, any additional
documents evidencing the subordination of this Lease with respect to any such
Encumbrance and the nondisturbance agreement of the holder of any such
Encumbrance. If the interest of Landlord in the Property is transferred pursuant
to or in lieu of proceedings for enforcement of any Encumbrance, Tenant shall
immediately and automatically attorn to the new owner, and this Lease shall
continue in full force and effect as a direct lease between the transferee and
Tenant on the terms and conditions set forth in this Lease. Landlord shall use
reasonable efforts to obtain a Subordination, Non-Disturbance and Attornment
Agreement from Landlord's current mortgagee with respect to this Lease in such
mortgagee's customary form. The costs, if any, incurred in securing such
agreement shall be at Tenant's expense.

     20.2 Mortgagee Protection. Tenant agrees to give any holder of any
          --------------------
Encumbrance covering any part of the Property ("Mortgagee"), by registered mail,
a copy of any notice of default served upon Landlord, provided that prior to
such notice Tenant has been notified in writing (by way of notice of assignment
of rents and leases, or otherwise) of the address of such Mortgagee. If Landlord
shall have failed to cure such default within thirty (30) days from the
effective date of such notice of default, then the Mortgagee shall have an
additional thirty (30) days within which to cure such default or if such default
cannot be cured within that time, then such additional time as may be necessary
to cure such default (including the time necessary to foreclose or otherwise
terminate its Encumbrance, if necessary to effect such cure), and this Lease
shall not be terminated so long as such remedies are being diligently pursued.

21.  ESTOPPEL CERTIFICATES AND FINANCIAL STATEMENTS.

     21.1 Estoppel Certificates. Within ten (10) business days after written
          ---------------------
request therefor, Tenant shall execute and deliver to Landlord, in a form
provided by or satisfactory to Landlord, a certificate stating that this Lease
is in full force and effect, describing any amendments or modifications hereto,
acknowledging that this Lease is subordinate or prior, as the case may be, to
any Encumbrance and stating any other information Landlord may reasonably
request, including the Term, the monthly Base Rent, the date to which Rent has
been paid, the amount of any security

                                      29
<PAGE>

deposit or prepaid rent, whether either party hereto is in default under the
terms of the Lease, and whether Landlord has completed its construction
obligations hereunder (if any). Any person or entity purchasing, acquiring an
interest in or extending financing with respect to the Property shall be
entitled to rely upon any such certificate. If Tenant fails to deliver such
certificate within ten (10) business days after Landlord's second written
request therefor, Tenant shall be liable to Landlord for any damages incurred by
Landlord including any profits or other benefits from any financing of the
Property or any interest therein which are lost or made unavailable as a result,
directly or indirectly, of Tenant's failure or refusal to timely execute or
deliver such estoppel certificate.

     21.2 Financial Statements. Within ten (10) days after written request
          --------------------
therefor, but not more than once a year, Tenant shall deliver to Landlord a copy
of the financial statements (including at least a year end balance sheet and a
statement of profit and loss) of Tenant (and of each guarantor of Tenant's
obligations under this Lease) for each of the two most recently completed years,
prepared in accordance with generally accepted accounting principles (and, if
such is Tenant's normal practice, audited by an independent certified public
accountant), all then available subsequent interim statements, and such other
financial information as may reasonably be requested by Landlord or required by
any Mortgagee.

22.  NOTICES. Any notice, demand, request, consent or approval that either party
desires or is required to give to the other party under this Lease shall be in
writing and shall be served personally, delivered by messenger or courier
service, or sent by U.S. certified mail, return receipt requested, postage
prepaid, addressed to the other party at the party's address for notices set
forth in the Basic Lease Information. Any notice required pursuant to any Laws
may be incorporated into, given concurrently with or given separately from any
notice required under this Lease. Notices shall be deemed to have been given and
be effective on the earlier of (a) receipt (or refusal of delivery or receipt);
or (b) one (1) day after acceptance by the independent service for delivery, if
sent by independent messenger or courier service, or three (3) days after
mailing if sent by mail in accordance with this Section. Either party may change
its address for notices hereunder, effective fifteen (15) days after notice to
the other party complying with this Section. If Tenant sublets the Premises,
notices from Landlord shall be effective on the subtenant when given to Tenant
pursuant to this Section.

23.  ATTORNEYS' FEES. In the event of any dispute between Landlord and Tenant in
any way related to this Lease, and whether involving contract and/or tort
claims, each party shall pay its own attorneys fees and costs except that the
non-prevailing party shall pay to the prevailing party all reasonable attorneys'
fees and costs and expenses of any type, without restriction by statute, court
rule or otherwise, incurred by the prevailing party in connection with any
action or proceeding (including any appeal and the enforcement of any judgment
or award), whether or not the dispute is litigated or prosecuted to final
judgment (collectively, "Fees"). The "prevailing party" shall be determined
based upon an assessment of which party's major arguments or positions taken in
the action or proceeding could fairly be said to have prevailed (whether by
compromise, settlement, abandonment by the other party of its claim or defense,
final decision, after any appeals, or otherwise) over the other party's major
arguments or positions on major disputed issues. Any Fees incurred in enforcing
a judgment shall be recoverable separately from

                                      30
<PAGE>

any other amount included in the judgment and shall survive and not be merged in
the judgment. The Fees shall be deemed an "actual pecuniary loss" within the
meaning of Bankruptcy Code Section 365(b)(1)(B), and notwithstanding the
foregoing, all Fees incurred by either party in any bankruptcy case filed by or
against the other party, from and after the order for relief until this Lease is
rejected or assumed in such bankruptcy case, will be "obligations of the debtor"
as that phrase is used in Bankruptcy Code Section 365(d)(3).

24.  QUIET POSSESSION. Subject to Tenant's full and timely performance of all of
Tenant's obligations under this Lease and subject to the terms of this Lease,
including Section 20 - Encumbrances, Tenant shall have the quiet possession of
the Premises throughout the Term as against any persons or entities lawfully
claiming by, through or under Landlord.

25. SECURITY MEASURES. Landlord may, but shall be under no obligation to,
implement security measures for the Property, such as the registration or search
of all persons entering or leaving the Building, requiring identification for
access to the Building, evacuation of the Building for cause, suspected cause,
or for drill purposes, the issuance of magnetic pass cards or keys for Building
or elevator access and other actions that Landlord deems necessary or
appropriate to prevent any threat of property loss or damage, bodily injury or
business interruption; provided, however, that such measures shall be
implemented in a way as not to inconvenience tenants of the Building
unreasonably. If Landlord uses an access card system, Landlord may require
Tenant to pay Landlord a deposit for each after-hours Building access card
issued to Tenant, in the amount specified in the Basic Lease Information. Tenant
shall be responsible for any loss, theft or breakage of any such cards, which
must be returned by Tenant to Landlord upon expiration or earlier termination of
the Lease. Landlord may retain the deposit for any card not so returned. If a
deposit is not required by Landlord, Landlord shall have the right to charge
Tenant for any card that is lost, stolen or broken or not returned upon
expiration or earlier termination of the Lease. Landlord shall at all times have
the right to change, alter or reduce any such security services or measures.
Tenant shall cooperate and comply with, and cause Tenant's Representatives and
Visitors to cooperate and comply with, such security measures. Landlord, its
agents and employees shall have no liability to Tenant or its Representatives or
Visitors for the implementation or exercise of, or the failure to implement or
exercise, any such security measures or for any resulting disturbance of
Tenant's use or enjoyment of the Premises.

26.  FORCE MAJEURE. If Landlord is delayed, interrupted or prevented from
performing any of its obligations under this Lease, including its obligations
under the Construction Rider (if any), and such delay, interruption or
prevention is due to fire, act of God, governmental act or failure to act, labor
dispute, unavailability of materials or any cause outside the reasonable control
of Landlord, then the time for performance of the affected obligations of
Landlord shall be extended for a period equivalent to the period of such delay,
interruption or prevention.

27.  RULES AND REGULATIONS. Tenant shall be bound by and shall comply with the
rules and regulations attached to and made a part of this Lease as Exhibit C to
                                                                   ---------
the extent those rules and regulations are not in conflict with the terms of
this Lease, as well as any reasonable nondiscriminatory rules and regulations
hereafter adopted by Landlord for all tenants of the Building, upon notice to
Tenant thereof (collectively, the "Building Rules"). Landlord shall not be

                                      31
<PAGE>

responsible to Tenant or to any other person for any violation of, or failure to
observe, the Building Rules by any other tenant or other person.

28.  LANDLORD'S LIABILITY. The term "Landlord," as used in this Lease, shall
mean only the owner or owners of the Building at the time in question. In the
event of any conveyance of title to the Building, then from and after the date
of such conveyance, the transferor Landlord shall be relieved of all liability
with respect to Landlord's obligations to be performed under this Lease after
the date of such conveyance. Notwithstanding any other term or provision of this
Lease, the liability of Landlord for its obligations under this Lease is limited
solely to Landlord's interest in the Building as the same may from time to time
be encumbered, and no personal liability shall at any time be asserted or
enforceable against any other assets of Landlord or against Landlord's partners
or members or its or their respective partners, shareholders, members,
directors, officers or managers on account of any of Landlord's obligations or
actions under this Lease.

29.  CONSENTS AND APPROVALS.

     29.1 Determination in Good Faith. Wherever the consent, approval, judgment
          ---------------------------
or determination of Landlord is required or permitted under this Lease, Landlord
may exercise its business judgment in granting or withholding such consent or
approval or in making such judgment or determination without reference to any
extrinsic standard of reasonableness, unless the specific provision contained in
this Lease providing for such consent, approval, judgment or determination
specifies that Landlord's consent or approval is not to be unreasonably
withheld, or that such judgment or determination is to be reasonable, or
otherwise specifies the standards under which Landlord may withhold its consent.
If it is determined that Landlord failed to give its consent where it was
required to do so under this Lease, Tenant shall be entitled to injunctive
relief but shall not to be entitled to monetary damages or to terminate this
Lease for such failure.

     29.2 No Liability Imposed on Landlord. The review and/or approval by
          --------------------------------
Landlord of any item or matter to be reviewed or approved by Landlord under the
terms of this Lease or any Exhibits or Addenda hereto shall not impose upon
Landlord any liability for the accuracy or sufficiency of any such item or
matter or the quality or suitability of such item for its intended use. Any such
review or approval is for the sole purpose of protecting Landlord's interest in
the Property, and no third parties, including Tenant or the Representatives and
Visitors of Tenant or any person or entity claiming by, through or under Tenant,
shall have any rights as a consequence thereof.

30.  WAIVER OF RIGHT TO JURY TRIAL. Landlord and Tenant waive their respective
rights to trial by jury of any contract or tort claim, counterclaim,
cross-complaint, or cause of action in any action, proceeding, or hearing
brought by either party against the other on any matter arising out of or in any
way connected with this Lease, the relationship of Landlord and Tenant, or
Tenant's use or occupancy of the Premises, including any claim of injury or
damage or the enforcement of any remedy under any current or future law,
statute, regulation, code, or ordinance.

31.  BROKERS. Landlord shall pay the fee or commission of the broker or brokers
identified in the Basic Lease Information (the "Broker") in accordance with
Landlord's separate written agreement with the Broker, if any. Tenant warrants
and represents to Landlord that in the

                                      32
<PAGE>

negotiating or making of this Lease neither Tenant nor anyone acting on Tenant's
behalf has dealt with any broker or finder who might be entitled to a fee or
commission for this Lease other than the Broker. Tenant shall indemnify and hold
Landlord harmless from any claim or claims, including costs, expenses and
attorney's fees incurred by Landlord asserted by any other broker or finder for
a fee or commission based upon any dealings with or statements made by Tenant or
Tenant's Representatives. Landlord agrees to indemnify and hold Tenant harmless
from and against any claim by third parties claiming by, through, or under
Landlord for commissions due or alleged to be due in connection with this Lease.

32. RELOCATION OF PREMISES. For the purpose of maintaining an economical and
proper distribution of tenants acceptable to Landlord throughout the Project,
Landlord shall have the right on one occasion during the Term to relocate the
Premises to a floor on or above the tenth (10th) floor within the Project,
provided that (a) the rentable and usable area of the new Premises is of
equivalent size to the existing Premises, subject to a variation of up to ten
percent (10%), provided that the Fixed Rent and Additional Rent payable
hereunder shall not be increased as a result of such relocation, (b) Landlord
shall pay the cost of providing tenant improvements in the new Premises, which
shall be substantially comparable in layout to those in the existing Premises,
and (c) Landlord shall pay reasonable costs (to the extent such costs are
submitted in writing to Landlord and approved in writing by Landlord prior to
such move) of moving Tenant's Trade Fixtures and personal property to the new
Premises and replacing stationery and business cards rendered incorrect as a
result of the relocation, and the costs of moving telephones and office
equipment and other personal property occasioned by the move. The new Premises
will be complete and ready for immediate occupancy by Tenant for the purpose of
doing business before the actual relocation takes place. Landlord shall deliver
to Tenant written notice of Landlord's election to relocate the Premises,
specifying the new location and the amount of rent payable therefor, at least
ninety (90) days prior to the date the relocation is to be effective.

33. ENTIRE AGREEMENT. This Lease, including the Exhibits and any Addenda
attached hereto, and the documents referred to herein, if any, constitute the
entire agreement between Landlord and Tenant with respect to the leasing of
space by Tenant in the Building, and supersede all prior or contemporaneous
agreements, understandings, proposals and other representations by or between
Landlord and Tenant, whether written or oral, all of which are merged herein.
Neither Landlord nor Landlord's agents have made any representations or
warranties with respect to the Premises, the Building, the Project or this Lease
except as expressly set forth herein, and no rights, easements or licenses shall
be acquired by Tenant by implication or otherwise unless expressly set forth
herein. The submission of this Lease for examination does not constitute an
option for the Premises and this Lease shall become effective as a binding
agreement only upon execution and delivery thereof by Landlord to Tenant.

34. MISCELLANEOUS. This Lease may not be amended or modified except by a writing
signed by Landlord and Tenant. Subject to Section 14 - Assignment and Subletting
and Section 28 - Landlord's Liability, this Lease shall be binding on and shall
inure to the benefit of the parties and their respective successors, assigns and
legal representatives. The determination that any provisions hereof may be void,
invalid, illegal or unenforceable shall not impair any other provisions hereof
and all such other provisions of this Lease shall remain in full force and
effect.

                                      33
<PAGE>

The unenforceability, invalidity or illegality of any provision of this Lease
under particular circumstances shall not render unenforceable, invalid or
illegal other provisions of this Lease, or the same provisions under other
circumstances. This Lease shall be construed and interpreted in accordance with
the laws (excluding conflict of laws principles) of the State in which the
Building is located. The provisions of this Lease shall be construed in
accordance with the fair meaning of the language used and shall not be strictly
construed against either party, even if such party drafted the provision in
question. When required by the context of this Lease, the singular includes the
plural. Wherever the term "including" is used in this Lease, it shall be
interpreted as meaning "including, but not limited to" the matter or matters
thereafter enumerated. The captions contained in this Lease are for purposes of
convenience only and are not to be used to interpret or construe this Lease. If
more than one person or entity is identified as Tenant hereunder, the
obligations of each and all of them under this Lease shall be joint and several.
Time is of the essence with respect to this Lease, except as to the conditions
relating to the delivery of possession of the Premises to Tenant. Neither
Landlord nor Tenant shall record this Lease; provided that, at the request of
either party, Landlord and Tenant shall, if appropriate, execute, acknowledge,
and deliver a notice of lease and a notice of termination of lease term, each in
recordable form. Such notices shall contain only the information required by law
for recording. Tenant hereby irrevocably appoints Landlord as Tenant's
attorney-in-fact (which appointment shall survive termination of the Term) with
full power of substitution to execute, acknowledge and deliver a notice of
termination of lease in Tenant's name if Tenant fails to do so within ten (10)
days after request therefor.

35.  AUTHORITY. If Tenant is a corporation, partnership, limited liability
company or other form of business entity, each of the persons executing this
Lease on behalf of Tenant warrants and represents that Tenant is a duly
organized and validly existing entity, that Tenant has full right and authority
to enter into this Lease and that the persons signing on behalf of Tenant are
authorized to do so and have the power to bind Tenant to this Lease. Tenant
shall provide Landlord upon request with evidence reasonably satisfactory to
Landlord confirming the foregoing representations. Landlord warrants and
represents that Landlord is a duly organized and validly existing entity, that
Landlord has full right and authority to enter into this Lease and that the
persons signing on behalf of Landlord are authorized to do so and have the power
to bind Landlord to this Lease. Landlord shall provide Tenant upon request with
evidence of such authority.

                                      34
<PAGE>

36.  VACANCY DURING LAST SIX MONTHS.

     If Tenant vacates substantially all of the Premises (or substantially all
of any major portion of the Premises, including a floor thereof) at any time
within the last six (6) months of the Term, Landlord may enter the Premises (or
such portion) and commence work necessary to prepare the space for future
tenants. The exercise of such right by Landlord will not affect Tenant's
obligations to pay Base Rent, Additional Rent, or any other additional charges
with respect to the Premises (or such portion), which obligations shall continue
without abatement until the end of the Term.

     IN WITNESS WHEREOF, Landlord and Tenant have entered into this Lease as a
sealed Massachusetts instrument as of the date first above written.

TENANT:                                       LANDLORD:

C-BRIDGE INTERNET SOLUTIONS, INC.             125 Summer Street Cornerstone LLC

By:  /s/                                      By:  /s/
    ----------------------------------------      ------------------------------
Name:  Rick Wester                            Name: A. Robert Paratte
      --------------------------------------       -----------------------------
Title:  CFO                                   Title:
       -------------------------------------         --------------------------

By:  /s/                                      By:
    ----------------------------------------      -----------------------------
Name:  Clifford B. Thompson                   Name:
      --------------------------------------        ----------------------------
Title:  VP & General Counsel                  Title:
       -------------------------------------        --------------------------

                                      35
<PAGE>

                                   EXHIBIT A
                                   ---------

                                 THE PREMISES
                                 ------------

Rough Drawing of floor plan omitted.

                               Exhibit A, Page 1
<PAGE>

                                   EXHIBIT B
                                   ---------

                              CONSTRUCTION RIDER
                              ------------------

     1.   Tenant Improvements. Landlord shall with reasonable diligence through
          -------------------
a contractor designated by Landlord (which contractor may be an affiliate of
Landlord) construct and install in the Premises the improvements and fixtures
provided for in this Construction Rider ("Tenant Improvements"). Upon request by
Landlord, Tenant shall designate in writing an individual authorized to act as
Tenant's Representative with respect to all approvals, directions and
authorizations pursuant to this Construction Rider.

          1.1  Plans. The Tenant Improvements shall be constructed substantially
               -----
as shown on the conceptual space plan for the Premises prepared by John Bryer
Architects who has been retained by Tenant as the space planner for the Premises
("Space Planner"), dated January 10, 2000 ("Space Plan").

     On or before April 1, 2000 Tenant will cause the Space Planner to
prepare and deliver to Landlord detailed plans and specifications sufficient to
permit the construction of the Tenant Improvements by Landlord's contractor
("Construction Documents"). Such Construction Documents shall be subject to
Landlord's approval, as provided in Article 6, and shall incorporate Building
standard finishes or such other finishes as Landlord may reasonably approve.
Landlord will bid the work to at least three (3) general contractors and provide
Tenant with a cost estimate for the work shown in the Construction Documents.
Tenant may include a general contractor and subcontractors (other than for
structural or building system trades) on the bid list. Tenant shall respond to
the Construction Documents and cost estimate within five (5) days after receipt
thereof, specifying any changes or modifications Tenant desires in the
Construction Documents. The Space Planner will then revise the Construction
Documents and resubmit them to Tenant and Landlord for their approval and
Landlord will provide Tenant with a revised cost estimate. Tenant shall approve
or disapprove the same within three (3) days after receipt. The revised
Construction Documents and cost estimate, as approved by Tenant and Landlord,
are hereinafter referred to as the "Final Construction Documents" and "Final
Cost Estimate," respectively.

     Additional interior decorating services and advice on the furnishing and
decoration of the Premises, such as the selection of fixtures, furnishings or
design of mill work, shall be provided by Tenant at its expense, but shall be
subject to the reasonable approval of Landlord.

     As part of the Tenant Improvements, Tenant shall have the right at its
sole cost and expense to install, operate, and maintain a separate security
system for access to the Premises ("Tenant's Security System") in accordance
with plans and specifications reasonably approved by Landlord. Upon the
expiration or earlier termination of the Lease, unless otherwise directed by
Landlord Tenant shall remove Tenant's Security System and repair any damage to
the Premises or Building caused by the installation and subsequent removal of
Tenant's Security System.

                               Exhibit B, Page 1
<PAGE>

          1.2  Construction. Upon approval by Landlord and Tenant of the Final
               ------------
Construction Documents and the Final Cost Estimate, Landlord shall proceed with
reasonable diligence to cause the Tenant Improvements to be Substantially
Completed on or prior to the Scheduled Commencement Date. The Tenant
Improvements shall be deemed to be "Substantially Completed" when they have been
completed in accordance with the Final Construction Documents except for
finishing details, minor omissions, decorations and mechanical adjustments of
the type normally found on an architectural "punch list". (The definition of
Substantially Completed shall also define the terms "Substantial Completion" and
"Substantially Complete.")

     Following Substantial Completion of the Tenant Improvements and before
Tenant takes possession of the Premises (or as soon thereafter as may be
reasonably practicable and in any event within 30 days after Substantial
Completion), Landlord and Tenant shall inspect the Premises and jointly prepare
a "punch list" of agreed items of construction remaining to be completed.
Landlord shall complete the items set forth in the punch list as soon as
reasonably possible and shall use reasonable efforts to complete the same within
thirty (30) days after the list of punchlist items has been agreed upon. Tenant
shall cooperate with and accommodate Landlord and Landlord's contractor in
completing the items on the punch list.

          1.3  Cost of Tenant Improvements. Landlord shall contribute
               ---------------------------
$32.00 per rentable square foot in the Premises (i.e., $629,824.00) toward the
cost of the design (including preparation of space plans and Construction
Documents), construction and installation of the Tenant Improvements, including
costs of cabling and wiring the Premises. The balance, if any, of the cost of
the Tenant Improvements ("Additional Cost"), including, but not limited to,
usual markups for overhead, supervision and profit, shall be paid by Tenant.
Tenant shall pay Landlord 50% of the Additional Cost based upon the Final Cost
Estimate prior to the commencement of construction of the Tenant Improvements.
The balance of the actual Additional Cost shall be paid to Landlord upon
Substantial Completion of the Tenant Improvements, within ten (10) days after
receipt of Landlord's invoice therefor. Landlord will use reasonable care in
preparing the cost estimates, but they are estimates only and do not limit
Tenant's obligation to pay for the actual Additional Cost of the Tenant
Improvements, whether or not it exceeds the estimated amounts. Tenant shall pay
Landlord a supervision fee equal to three percent (3%) of the total cost of the
Tenant Improvements in connection with Landlord's performance of the Tenant
Improvements. In connection with the Tenant Improvements, Landlord shall, at its
expense, remove the existing internal staircase between the 19/th/ and 20/th/
floors and fill in such stairway opening.

          1.4  Changes. If Tenant requests any change, addition or alteration in
               -------
or to any Final Construction Documents ("Changes") Landlord shall cause the
Space Planner to prepare additional Plans implementing such Change. Tenant shall
pay the cost of preparing additional Plans within ten (10) days after receipt of
Landlord's invoice therefor. As soon as practicable after the completion of such
additional Construction Documents, Landlord shall notify Tenant of the estimated
cost of the Changes. Within three (3) working days after receipt of such cost
estimate, Tenant shall notify Landlord in writing whether Tenant approves the
Change. If Tenant approves the Change, Landlord shall proceed with the Change
and Tenant shall be liable for any

                               Exhibit B, Page 2
<PAGE>

Additional Cost resulting from the Change. If Tenant fails to approve the Change
within such three (3) day period, construction of the Tenant Improvements shall
proceed as provided in accordance with the original Construction Documents.

          1.5  Delays. Tenant shall be responsible for, and shall pay to
               ------
Landlord, any and all costs and expenses incurred by Landlord in connection with
any delay in the commencement or completion of any Tenant Improvements and any
increase in the cost of Tenant Improvements caused by (i) Tenant's failure to
submit information to the Space Planner or approve any Space Plan, Construction
Documents or cost estimates within the time periods required herein, (ii) any
delays in obtaining any items or materials constituting part of the Tenant
Improvements requested by Tenant, (iii) any Changes, or (iv) any other delay
requested or caused by Tenant (collectively, "Tenant Delays").

     2.   Delivery of Premises. Upon Substantial Completion of the Tenant
          --------------------
Improvements, Landlord shall deliver possession of the Premises to Tenant. If
Landlord has not Substantially Completed the Tenant Improvements and tendered
possession of the Premises to Tenant on or before the Scheduled Commencement
Date specified in Section 2 - Term; Possession of the Lease, or if Landlord is
unable for any other reason to deliver possession of the Premises to Tenant on
or before such date, neither Landlord nor its representatives shall be liable to
Tenant for any damage resulting from the delay in completing such construction
obligations and/or delivering possession to Tenant and the Lease shall remain in
full force and effect unless and until it is terminated under the express
provisions of this Section. If any delays in Substantially Completing the Tenant
Improvements are attributable to Tenant Delays, then the Premises shall be
deemed to have been Substantially Completed and delivered to Tenant on the date
on which Landlord could have Substantially Completed the Premises and tendered
the Premises to Tenant but for such Tenant Delays.

     3.   Access to Premises. Landlord shall allow Tenant and Tenant's
          ------------------
Representatives to enter the Premises prior to the Commencement Date to permit
Tenant to make the Premises ready for its use and occupancy; provided, however,
that prior to such entry of the Premises, Tenant shall provide evidence
reasonably satisfactory to Landlord that Tenant's insurance, as described in
Section 11.1 - Tenant's Insurance of the Lease, shall be in effect as of the
time of such entry. Such permission may be revoked at any time upon twenty-four
(24) hours' notice, and Tenant and its Representatives shall not interfere with
Landlord or Landlord's contractor in completing the Building or the Tenant
Improvements.

         Tenant agrees that Landlord shall not be liable in any way for any
injury, loss or damage which may occur to any of Tenant's property placed upon
or installed in the Premises prior to the Commencement Date, the same being at
Tenant's sole risk, and Tenant shall be liable for all injury, loss or damage to
persons or property arising as a result of such entry into the Premises by
Tenant or its Representatives.

     4.   Ownership of Tenant Improvements. All Tenant Improvements, whether
          --------------------------------
installed by Landlord or Tenant, shall become a part of the Premises, shall be
the property of Landlord and, subject to the provisions of the Lease, shall be
surrendered by Tenant with the Premises,

                               Exhibit B, Page 3
<PAGE>

without any compensation to Tenant, at the expiration or termination of the
Lease in accordance with the provisions of the Lease.

                               Exhibit B, Page 4
<PAGE>

                                   EXHIBIT C
                                   ---------

                                BUILDING RULES
                                --------------

     The following Building Rules are additional provisions of the foregoing
Lease to which they are attached. The capitalized terms used herein have the
same meanings as these terms are given in the Lease.

     1.   Use of Common Areas. Tenant will not obstruct the sidewalks, halls,
          -------------------
passages, exits, entrances, elevators or stairways of the Building ("Common
Areas"), and Tenant will not use the Common Areas for any purpose other than
ingress and egress to and from the Premises. The Common Areas, except for the
sidewalks, are not open to the general public and Landlord reserves the right to
control and prevent access to the Common Areas of any person whose presence, in
Landlord's opinion, would be prejudicial to the safety, reputation and interests
of the Building and its tenants.

     2.   No Access to Roof. Tenant has no right of access to the roof of the
          -----------------
Building and will not install, repair or replace any antenna, aerial, aerial
wires, fan, air-conditioner or other device on the roof of the Building, without
the prior written consent of Landlord. Any such device installed without such
written consent is subject to removal at Tenant's expense without notice at any
time. In any event Tenant will be liable for any damages or repairs incurred or
required as a result of its installation, use, repair, maintenance or removal of
such devices on the roof and agrees to indemnify and hold harmless Landlord from
any liability, loss, damage, cost or expense, including reasonable attorneys'
fees, arising from any activities of Tenant or of Tenant's Representatives on
the roof of the Building.

     3.   Signage. No sign, placard, picture, name, advertisement or notice
          -------
visible from the exterior of the Premises will be inscribed, painted, affixed or
otherwise displayed by Tenant on or in any part of the Building without the
prior written consent of Landlord. Landlord reserves the right to adopt and
furnish Tenant with general guidelines relating to signs in or on the Building.
All approved signage will be inscribed, painted or affixed at Tenant's expense
by a person approved by Landlord, which approval will not be unreasonably
withheld.

     4.   Prohibited Uses. The Premises will not be used for manufacturing,
          ---------------
for the storage of merchandise held for sale to the general public, for lodging
or for the sale of goods to the general public. Tenant will not permit any food
preparation on the Premises except that Tenant may use Underwriters' Laboratory
approved equipment for brewing coffee, tea, hot chocolate and similar beverages
so long as such use is in accordance with all applicable federal, state and city
laws, codes, ordinances, rules and regulations.

     5.   Janitorial Services. Tenant will not employ any person for the
          -------------------
purpose of cleaning the Premises or permit any person to enter the Building for
such purpose other than Landlord's janitorial service, except with Landlord's
prior written consent. Tenant will not necessitate, and will be liable for the
cost of, any undue amount of janitorial labor by reason of Tenant's carelessness
in or indifference to the preservation of good order and cleanliness in the
Premises. Janitorial service will not be furnished to areas in the Premises on
nights when such

                               Exhibit C, Page 1
<PAGE>

areas are occupied after 7:00 p.m., unless such service is extended by written
agreement to a later hour in specifically designated areas of the Premises.

     6.   Keys and Locks. Landlord will furnish Tenant, free of charge, two
          --------------
keys to each door or lock in the Premises. Landlord may make a reasonable charge
for any additional or replacement keys. Tenant will not duplicate any keys,
alter any locks or install any new or additional lock or bolt on any door of its
Premises or on any other part of the Building without the prior written consent
of Landlord and, in any event, Tenant will provide Landlord with a key for any
such lock. On the termination of the Lease, Tenant will deliver to Landlord all
keys to any locks or doors in the Building which have been obtained by Tenant.

     7.   Freight. Upon not less than twenty-four hours prior notice to
          -------
Landlord, which notice may be oral, an elevator will be made available for
Tenant's use for transportation of freight, subject to such scheduling as
Landlord in its discretion deems appropriate. Tenant shall not transport freight
in loads exceeding the weight limitations of such elevator. Landlord reserves
the right to prescribe the weight, size and position of all equipment,
materials, furniture or other property brought into the Building, and no
property will be received in the Building or carried up or down the freight
elevator or stairs except during such hours and along such routes and by such
persons as may be designated by Landlord. Landlord reserves the right to require
that heavy objects will stand on wood strips of such length and thickness as is
necessary to properly distribute the weight. Landlord will not be responsible
for loss of or damage to any such property from any cause, and Tenant will be
liable for all damage or injuries caused by moving or maintaining such property.

     8.   Nuisances and Dangerous Substances. Tenant will not conduct itself
          ----------------------------------
or permit Tenant's Representatives or Visitors to conduct themselves, in the
Premises or anywhere on or in the Property in a manner which is offensive or
unduly annoying to any other Tenant or Landlord's property managers. Tenant will
not install or operate any phonograph, radio receiver, musical instrument, or
television or other similar device in any part of the Common Areas and shall not
operate any such device installed in the Premises in such manner as to disturb
or annoy other tenants of the Building. Tenant will not use or keep in the
Premises or the Property any kerosene, gasoline or other combustible fluid or
material other than limited quantities thereof reasonably necessary for the
maintenance of office equipment, or, without Landlord's prior written approval,
use any method of heating or air conditioning other than that supplied by
Landlord. Tenant will not use or keep any foul or noxious gas or substance in
the Premises or permit or suffer the Premises to be occupied or used in a manner
offensive or objectionable to Landlord or other occupants of the Building by
reason of noise, odors or vibrations, or interfere in any way with other tenants
or those having business therein. Tenant will not bring or keep any animals in
or about the Premises or the Property.

     9.   Building Name and Address. Without Landlord's prior written consent,
          -------------------------
Tenant will not use the name of the Building in connection with or in promoting
or advertising Tenant's business except as Tenant's address.

                               Exhibit C, Page 2
<PAGE>

     10.    Building Directory and Signage. A directory for the Building will
            ------------------------------
be provided for the display of the name and location of tenants. Landlord
reserves the right to approve any additional names Tenant desires to place in
the directory and, if so approved, Landlord may assess a reasonable charge for
adding such additional names. Tenant's name and suite number shall be displayed
on building standard signage in the elevator lobby of any multi-tenant floor on
which the Premises are located. If the Premises consist of an entire floor,
Tenant at its expense may affix a sign displaying its name in the elevator lobby
of such floor, subject to Landlord's prior approval.

     11.    Window Coverings. No curtains, draperies, blinds, shutters, shades,
            ----------------
awnings, screens or other coverings, window ventilators, hangings, decorations
or similar equipment shall be attached to, hung or placed in, or used in or with
any window of the Building without the prior written consent of Landlord, and
Landlord shall have the right to control all lighting within the Premises that
may be visible from the exterior of the Building.

     12.    Floor Coverings. Tenant will not lay or otherwise affix linoleum,
            ---------------
tile, carpet or any other floor covering to the floor of the Premises in any
manner except as approved in writing by Landlord. Tenant will be liable for the
cost of repair of any damage resulting from the violation of this rule or the
removal of any floor covering by Tenant or its contractors, employees or
invitees.

     13.    Wiring and Cabling Installations. Landlord will direct Tenant's
            --------------------------------
electricians and other vendors as to where and how data, telephone, and
electrical wires and cables are to be installed. No boring or cutting for wires
or cables will be allowed without the prior written consent of Landlord. The
location of burglar alarms, smoke detectors, telephones, call boxes and other
office equipment affixed to the Premises shall be subject to the written
approval of Landlord.

     14.    Office Closing Procedures. Tenant will see that the doors of the
            -------------------------
Premises are closed and locked and that all water faucets, water apparatus and
utilities are shut off before Tenant or its employees leave the Premises, so as
to prevent waste or damage. Tenant will be liable for all damage or injuries
sustained by other tenants or occupants of the Building or Landlord resulting
from Tenant's carelessness in this regard or violation of this rule. Tenant will
keep the doors to the Building corridors closed at all times except for ingress
and egress.

     15.    Plumbing Facilities. The toilet rooms, toilets, urinals, wash bowls
            -------------------
and other apparatus shall not be used for any purpose other than that for which
they were constructed and no foreign substance of any kind whatsoever shall be
disposed of therein. Tenant will be liable for any breakage, stoppage or damage
resulting from the violation of this rule by Tenant, its employees or invitees.

     16.    Use of Hand Trucks. Tenant will not use or permit to be used in the
            ------------------
Premises or in the Common Areas any hand trucks, carts or dollies except those
equipped with rubber tires and side guards or such other equipment as Landlord
may approve.

                               Exhibit C, Page 3
<PAGE>

     17.    Refuse. Tenant shall store all Tenant's trash and garbage within
            ------
the Premises or in other facilities designated By Landlord for such purpose.
Tenant shall not place in any trash box or receptacle any material which cannot
be disposed of in the ordinary and customary manner of removing and disposing of
trash and garbage in the city in which the Building is located without being in
violation of any law or ordinance governing such disposal. All trash and garbage
removal shall be made in accordance with directions issued from time to time by
Landlord, only through such Common Areas provided for such purposes and at such
times as Landlord may designate. Tenant shall comply with the requirements of
any recycling program adopted by Landlord for the Building.

     18.    Soliciting. Canvassing, peddling, soliciting and distribution of
            ----------
handbills or any other written materials in the Building are prohibited, and
Tenant will cooperate to prevent the same.

     19.    Parking. Tenant will use, and cause Tenant's Representatives and
            -------
Visitors to use, any parking spaces to which Tenant is entitled under the Lease
in a manner consistent with Landlord's directional signs and markings in the
Parking Facility. Specifically, but without limitation, Tenant will not park, or
permit Tenant's Representatives or Visitors to park, in a manner that impedes
access to and from the Building or the Parking Facility or that violates space
reservations for handicapped drivers registered as such with the Massachusetts
Registry of Motor Vehicles. Landlord may use such reasonable means as may be
necessary to enforce the directional signs and markings in the Parking Facility,
including but not limited to towing services, and Landlord will not be liable
for any damage to vehicles towed as a result of non-compliance with such parking
regulations.

     20.    Fire, Security and Safety Regulations. Tenant will comply with all
            -------------------------------------
safety, security, fire protection and evacuation measures and procedures
established by Landlord or any governmental agency.

     21.    Responsibility for Theft. Tenant assumes any and all responsibility
            ------------------------
for protecting the Premises from theft, robbery and pilferage, which includes
keeping doors locked and other means of entry to the Premises closed.

     22.    Sales and Auctions. Tenant will not conduct or permit to be
            ------------------
conducted any sale by auction in, upon or from the Premises or elsewhere in the
Property, whether said auction be voluntary, involuntary, pursuant to any
assignment for the payment of creditors or pursuant to any bankruptcy or other
insolvency proceeding.

     23.    Thermostats. Office Tenants shall not tamper with or attempt to
            -----------
adjust temperature control thermostats in their leased premises. Landlord shall
make adjustments in thermostats upon request by tenants.

     24.    Emergency Stairs. Building emergency stairs shall be used only for
            ----------------
emergency purposes, unless specifically approved by Landlord in its sole
discretion.

                               Exhibit C, Page 4
<PAGE>

     25.   Non-Smoking Policy. The common areas of the Project, including
           -----------------
without limitation the garage and the exterior areas adjacent to building
entrances, are non smoking areas. Tenants who permit smoking within their leased
premises shall, at their sole cost and expense, install filtering systems
sufficient to prevent smoke and odors from entering other tenants' premises, the
plenum space above the leased premises, or the building's HVAC system. Upon
request from Landlord, Tenant shall inform its employees of the building's
non-smoking policy in building common areas and shall take reasonable measures
to enforce the policy with respect to its employees.

     26.   Waiver of Rules. Landlord may waive any one or more of these
           ---------------
Building Rules for the benefit of any particular tenant or tenants, but no such
waiver by Landlord will be construed as a waiver of such Building Rules in favor
of any other tenant or tenants nor prevent Landlord from thereafter enforcing
these Building Rules against any or all of the tenants of the Building.

     27.   Effect on Lease. These Building Rules are in addition to, and shall
           ---------------
not be construed to in any way modify or amend, in whole or in part, the terms,
covenants, agreements and conditions of the Lease. Violation of these Building
Rules constitutes a failure to fully perform the provisions of the Lease, as
referred to in Section 15.1 - "Events of Default".

     28.   Non-Discriminatory Enforcement. Subject to the provisions of the
           ------------------------------
Lease (and the provisions of other leases with respect to other tenants),
Landlord shall use reasonable efforts to enforce these Building Rules in a
non-discriminatory manner, but in no event shall Landlord have any liability for
any failure or refusal to do so (and Tenant's sole and exclusive remedy for any
such failure or refusal shall be injunctive relief preventing Landlord from
enforcing any of the Building Rules against Tenant in a manner that
discriminates against Tenant).

     29.   Additional and Amended Rules. Landlord reserves the right to
           ----------------------------
rescind or amend these Building Rules and/or adopt any other and reasonable
rules and regulations as in its judgment may from time to time be needed for the
safety, care and cleanliness of the Building and for the preservation of good
order therein.
<PAGE>

                                   EXHIBIT D
                                   ---------

                               LANDLORD SERVICES
                               -----------------

1.   Water used by the building standard cooling, drinking and sanitation
     systems, and for maintenance and janitorial services.

2.   Central heat and air conditioning in season, at such temperatures and
     in such amounts as are from time to time furnished
     to tenants in comparable buildings in downtown Boston, or as may be
     permitted to controlled by applicable laws, ordinances, rules and
     regulations.

3.   Maintenance, repairs, structural and exterior maintenance (including
     exterior glass and glazing), painting and electric lighting service for all
     Common Areas, Building Common Areas and General Common Areas in the manner
     and to the extent customarily provided by landlords in first-class office
     buildings in Boston.

4.   Janitorial service after Business Hours on Business Days.

5.   Electricity for typewriters, voice writers, calculating machines, low
     consumption duplicating machines, low consumption electronic data
     processing equipment, and other machines of similar low electrical
     consumption (it being agreed that Tenant's total consumption for such items
     shall not exceed six (6) watts per square foot of Net Rentable Area per
     month at 120 volts).

6.   Initial lamps, bulbs, starters and ballasts for building standard fixtures
     used within the Leased Premises, and electricity for lighting such
     fixtures.

7.   Security for the Building.

8.   Public elevator service serving the floors on which the Leased Premises are
     situated, including a service elevator.

                               Exhibit D, Page 1
<PAGE>

9.   A general directory board or electronic device on which Tenant shall be
     entitled to have its name shown.

                               Exhibit D, Page 2
<PAGE>

                                   EXHIBIT E
                                   ---------

                          ADDITIONAL PROVISIONS RIDER
                          ---------------------------

1.   PARKING.
     -------

     (a) Tenant's Parking Rights. Landlord shall provide Tenant, on an
         -----------------------
unassigned and non-exclusive basis, for use by Tenant and Tenant's
Representatives and Visitors, at the users' sole risk, thirteen (13) parking
spaces in the Parking Facility. The parking spaces to be made available to
Tenant hereunder may contain a reasonable mix of spaces for compact cars and up
to ten percent (10%) of the unassigned spaces may also be designated by Landlord
as Building visitors' parking.

     (b) Availability of Parking Spaces. Landlord shall take reasonable actions
         ------------------------------
to ensure the availability of the parking spaces leased by Tenant, but Landlord
does not guarantee the availability of those spaces at all times against the
actions of other tenants of the Building and users of the Parking Facility.
Access to the Parking Facility may, at Landlord's option, be regulated by card,
pass, bumper sticker, decal or other appropriate identification issued by
Landlord. Landlord retains the right to revoke the parking privileges of any
user of the Parking Facility who violates the rules and regulations governing
use of the Parking Facility (and Tenant shall be responsible for causing any
employee of Tenant or other person using parking spaces allocated to Tenant to
comply with all parking rules and regulations).

     (c) Monthly Parking Rental. Tenant shall pay to Landlord, as monthly rent
         ----------------------
for the parking spaces leased by Tenant hereunder, a "Monthly Parking Rental"
per space, which shall be the "Prevailing Parking Rental" for such parking
spaces in effect from time to time. The Prevailing Parking Rental shall be
determined by Landlord, based on the monthly rental charged by Landlord from
time to time for spaces in the Parking Facility, and the unassigned or reserved
nature of such parking spaces. The Building's unreserved parking rate is
currently $325.00 per space per month. Tenant's Monthly Parking Rental shall be
paid on the first day of each month during the Term of this Lease; provided,
however, that in the event Tenant fails to pay Tenant's Monthly Parking Rental
when due, Landlord may assess a late charge of $50.00 on the delinquent amount,
which late charge shall be in addition to the late charge and interest that may
be charged pursuant to Section 16.1 - Late Charge and Interest in the Lease, and
provided further that in the event: (i) Tenant fails to pay Tenant's Monthly
Parking Rental within thirty (30) days of Landlord's notice of such delinquency,
or (ii) Tenant does not use any parking spaces for a period of more than sixty
(60) days, Landlord shall have the right by notice to Tenant permanently to
terminate Tenant's rights to use parking spaces hereunder, whether or not
Landlord declares a default under the Lease.

     (d) Assignment and Subletting. Notwithstanding any other provision of the
         -------------------------
Lease to the contrary, Tenant shall not assign its rights to the parking spaces
or any interest therein, or

                               Exhibit E, Page 1
<PAGE>

sublease or otherwise allow the use of all or any part of the parking spaces to
or by any other person, except with Landlord's prior written consent, which may
be granted or withheld by Landlord in its sole discretion, provided that the
parking spaces hereunder may be transferred as part of any assignment of this
Lease or a sublease that is permitted or approved under Article 14 of the Lease.
In the event of any separate assignment or sublease of parking space rights that
is approved by Landlord, Landlord shall be entitled to receive, as additional
Rent hereunder, one hundred percent (100%) of any profit received by Tenant in
connection with such assignment or sublease.

     (e)  Condemnation, Damage or Destruction. In the event the Parking Facility
          -----------------------------------
is the subject of a Condemnation, or is damaged or destroyed, and this Lease is
not terminated, and if in such event the available number of parking spaces in
the Parking Facility is permanently reduced, then Tenant's rights to use parking
spaces hereunder may, at the election of Landlord, thereafter be reduced in
proportion to the reduction of the total number of parking spaces in the Parking
Facility, and the Monthly Parking Rental payable hereunder shall be reduced
proportionately. In such event, Landlord reserves the right to reduce the number
of parking spaces to which Tenant is entitled or to relocate some or all of the
parking spaces to which Tenant is entitled to other areas in the Parking
Facility.

2.   EXTENSION OPTION.
     ----------------

     (a)  Provided that C-Bridge Internet Solutions, Inc. has not assigned this
Lease or sublet more than 25% of the Rentable Area of the Premises other than to
a Successor or Affiliate under Article 14 (it being intended that all rights
pursuant to this provision are and shall be personal to the original Tenant or
its Successor or Affiliate under Article 14 under this Lease and shall not be
transferable or exercisable for the benefit of any other Transferee), and
provided Tenant is not in default beyond applicable notice and grace periods
under this Lease at the time of exercise or at any time thereafter until the
beginning of any such extension of the Term, Tenant shall have the option (the
"Extension Option") to extend the Term for one (1) additional period of five (5)
years (the "Extension Period"), subject to and in accordance with the terms and
conditions of this Section. The exercise of any Extension Option by Tenant shall
be irrevocable and shall cover the entire Premises leased by Tenant pursuant to
this Lease. Any Extension Option shall terminate if not exercised precisely in
the manner provided herein. Any extension of the Term shall be upon all the
terms and conditions set forth in this Lease and all Exhibits thereto, except
that: (i) Tenant shall have no further option to extend the Term of the Lease,
other than as specifically set forth herein; (ii) Landlord shall not be
obligated to contribute funds toward the cost of any remodeling, renovation,
alteration or improvement work in the Premises.

     If Tenant wishes to consider exercising the Extension Option, Tenant shall
first give written notice to Landlord, at least twelve (12) months, but not more
than fifteen (15) months, prior to the expiration of the initial Term, of
Tenant's request for Landlord's determination of the Base Rent for the Extension
Period (the "Extension Rent"). The Extension Rent shall be the Fair Market Base
Rental for the Premises (as determined hereunder), but not less than the Base
Rent in effect immediately prior to the Extension Period. Failure timely to give
a notice as

                               Exhibit E, Page 2
<PAGE>

specified under this subsection (a) shall constitute an irrevocable waiver of
Tenant's right to extend the Term.

     (b)  If Tenant timely delivers a notice under subsection (a) above,
Landlord shall furnish Tenant with Landlord's proposed Extension Rent no later
than ten (10) months prior to the date the Term is then scheduled to expire.

     (c)  On or before the date that is one (1) month after Landlord furnishes
the amount of its proposed Extension Rent to Tenant under subsection (b) above,
Tenant shall either (i) waive the Extension Option, (ii) exercise the Extension
Option by giving Landlord notice to such effect accepting Landlord's proposed
Extension Rent, or (iii) exercise the Extension Option but cause the matter of
the Extension Rent to be submitted to arbitration in accordance with subsection
(f) below by giving Landlord notice to such effect, which notice shall state
Tenant's determination of the Fair Market Base Rental (as hereinafter defined).
Failure timely to give a notice exercising the Extension Option as specified
under this subsection (c) shall constitute an irrevocable waiver of Tenant's
right to extend the Term.

     (d)  If Tenant shall exercise the Extension Option in accordance with
this Section, the provisions of this Section shall be self-operative, but upon
request by either party after determination of the Extension Rent, the parties
shall execute an agreement specifying the Extension Rent and acknowledging the
extension of the Term.

     (e)  "Fair Market Base Rental" shall mean the fair market rent for the
Premises for the Extension Period under the terms of this Lease, as though the
Premises had been maintained in the condition the Premises are required to be
maintained under the Lease. In making such determination, when reference is made
to lease transactions for comparable space in the Building or other comparable
buildings in downtown Boston, Massachusetts, appropriate adjustments shall be
made to the rental rates for such transactions to take into account all relevant
factors. Fair Market Base Rental shall also reflect the then prevailing rental
structure for comparable office buildings in the general vicinity of the
Property, so that if, for example, at the time Fair Market Base Rental is being
determined the prevailing rental structure for comparable space and for
comparable lease terms includes periodic rental adjustments or escalations, Fair
Market Base Rental shall reflect such rental structure.

     (f)  If Tenant elects to proceed under subsection (c)(iii) (exercising the
Extension Option and submitting the matter of the Extension Rent to arbitration
by determination of the Fair Market Base Rental), Landlord and Tenant shall
mutually select a licensed real estate broker who is active in the leasing of
first-class high-rise office space in the general vicinity of the Property.
Landlord shall submit Landlord's determination of Fair Market Base Rental and
Tenant shall submit Tenant's determination of Fair Market Base Rental to such
broker, at such time or times and in such manner as Landlord and Tenant shall
agree (or as directed by the broker if Landlord and Tenant do not promptly
agree). The broker shall select either Landlord's or Tenant's final
determination of the Fair Market Base Rental, submitted at the commencement of
the broker determination process, as the Extension Rent, and such determination
of the Extension Rent shall be binding on Landlord and Tenant. If Tenant's
determination of the Fair

                               Exhibit E, Page 3
<PAGE>

Market Base Rental is selected as the Extension Rent, then Landlord shall bear
all of the broker's cost and fees. If Landlord's determination of the Fair
Market Base Rental is selected as the Extension Rent, then Tenant shall bear all
of the broker's cost and fees.

     (g)  In the event the Fair Market Base Rental for any Extension Period
has not been determined at such time as Tenant is obligated to pay Base Rent for
such Extension Period, Tenant shall pay as Base Rent pending such determination,
the Base Rent in effect for such space immediately prior to the Extension
Period; provided, that upon the determination of the applicable Fair Market Base
Rental, any shortage of Base Rent paid, together with interest at the rate
specified in the Lease, shall be paid to Landlord by Tenant.

     (h)  In no event shall the Base Rent during any Extension Period (adjusted
to reflect the Base Operating Costs and Base Taxes in effect immediately prior
to such Extension Period) be less than the Base Rent in effect immediately prior
to such Extension Period.

     (i)  The term of this Lease, whether consisting of the Initial Term alone
or the Initial Term as extended by any Extension Period (if any Extension Option
is exercised), is referred to in this Lease as the "Term."

3.   RIGHT OF FIRST OFFER.
     --------------------

     (a)  Provided that C-Bridge Internet Solutions, Inc. has not assigned this
Lease or sublet more than 25% of the Premises other than to a Successor or
Affiliate under Article 14 (it being intended that all rights pursuant to this
provision are and shall be personal to the original Tenant under this Lease or
its Successor or Affiliate under Article 14 and shall not be transferable or
exercisable for the benefit of any other Transferee), and provided Tenant is not
in default beyond applicable notice and grace periods under this Lease at the
time of the exercise of any such right or at any time thereafter until delivery
of possession of the space to Tenant, subject to any and all rights granted by
Landlord or asserted by others with respect to such space (including renewal and
extension rights and rights of first offer, first negotiation, first refusal or
other expansion rights and including the rights that Landlord may heretofore or
hereafter grant to Charles Schwab, Inc., Robinson Humphrey/Salomon Brothers,
LLC, or their affiliates), and subject to Landlord's right to extend or renew
any then existing lease of the space or otherwise to lease the space to any
tenant, subtenant or other occupant of the space, Tenant shall have a one-time
right of first offer to lease the following space in the Building: Any
contiguous space on the 18th floor.

     (b)  Such right of first offer (i) may only be exercised with respect to
space which has been previously leased and becomes vacant during the Term
following expiration or other termination of the previous lease, and (ii) may
only be exercised with respect to all of the space being offered by Landlord. If
any space qualifying for such right of first offer becomes available, Landlord
shall offer to lease such space to Tenant at the same rent and on the same terms
that Landlord intends to offer to other prospective tenants. Tenant shall have
ten (10) Business Days following receipt of Landlord's offer with respect to any
such space within which to notify Landlord in writing of its intention to lease
such space, and such notice, if given by Tenant, shall constitute an acceptance
of Landlord's terms for the lease of such space. If Tenant

                               Exhibit E, Page 4
<PAGE>

exercises such right of first offer, the space to be leased by Tenant shall be
leased on the same terms and conditions as are contained in this Lease except
for the economic and other terms specifically set forth in Landlord's notice,
and the parties shall execute an amendment to this Lease to include such space
in the Premises and otherwise to provide for the leasing of such space on such
terms. If Tenant fails so to exercise Tenant's right of first offer within such
ten (10) Business Day period, Landlord may thereafter lease such space to other
prospective tenants; provided, however, that if Landlord proposes to lease such
space at an effective rent that is less than ninety percent (90%) of the
effective rent proposed to Tenant, or upon other terms which are substantially
more favorable to the prospective tenant, Landlord shall first re-offer such
space to Tenant at such lower rent and/or more favorable terms in accordance
with the provisions of this paragraph.

     (c)  If Tenant does not lease the right of first offer space from Landlord
when it is first offered to Tenant by Landlord or when it is re-offered to
Tenant because the economic terms first offered to Tenant have materially
changed, as described in the last sentence of paragraph (b) above, then this
right of first offer shall terminate and Tenant shall have no further rights to
lease any of the right of first offer space.

4.   LETTER OF CREDIT

     (a)  Tenant shall deliver to Landlord a clean, unconditional, irrevocable,
transferable letter of credit (the "Letter of Credit") in form, and issued by a
financial institution ("Issuer") satisfactory to Landlord in Landlord's sole
discretion. The Letter of Credit shall be in the amount of Seven Hundred Seventy
Seven Thousand Four Hundred Thirty Nine and 00/100 Dollars ($777,439.00), name
Landlord as the beneficiary thereunder, and provide that draws thereunder will
be honored upon receipt by Issuer of a written statement signed by Landlord or
Landlord's authorized agent stating that Landlord is entitled to draw down on
the Letter of Credit pursuant to the terms of this Lease. Landlord shall be
entitled to draw the entire amount under the Letter of Credit if either (i)
Tenant does not deliver to Landlord a replacement letter of credit from Issuer
or another financial institution satisfactory to Landlord in the amount and form
of the initial Letter of Credit no later than one month before the expiration
date of the then existing Letter of Credit, or (ii) upon a proposed sale or
lease of the Building Tenant does not deliver to any new landlord a replacement
Letter of Credit pursuant to the provisions of (d) below. If Tenant is in
default under the Lease beyond any applicable notice and cure period, Landlord
shall be entitled to draw under the Letter of Credit only an amount equal to the
amount of any monetary default as defined below (or, only if partial draws are
not permitted, the entire amount of the Letter of Credit). As used herein,
"monetary default" means any delinquent installment of Base Rent, Additional
Rent or Rent under this Lease (as and when Tenant fails to pay the same beyond
any applicable notice and cure period contained in this Lease), plus any damages
to which Landlord is entitled under the Lease. Landlord agrees that the Letter
of Credit may also provide for partial draws by Landlord. To the extent not
applied by Landlord pursuant to the provisions of the Lease any amount drawn
under the Letter of Credit shall be held or applied by Landlord as a Security
Deposit, subject to the terms of Section 4 of this Lease.

                               Exhibit E, Page 5
<PAGE>

     (b) The Letter of Credit shall be issued and delivered to Landlord within
fifteen (15) days after complete execution of this Lease by Landlord and Tenant.
If Tenant Fails to deliver to Landlord the Letter of Credit when required, such
failure shall constitute an Event of Default under the Lease.

     (c) Tenant shall not assign or encumber or attempt to assign or encumber
the Letter of Credit and neither Landlord nor its successors or assign shall be
bound by any such assignment or encumbrance or attempted assignment or
encumbrance.

     (d) If Landlord shall be holding the Letter of Credit as security, then, in
the event of a proposed sale or lease of the Building by Landlord, Tenant will,
upon ten (10) Business Days' notice, at its sole cost and expense, cause the
issuing bank to consent to the assignment or to issue a substitute letter of
credit on identical terms except for the stated beneficiary, from the same
issuing bank or another bank acceptable to Landlord in Landlord's sole
discretion, naming the new landlord as the beneficiary thereof upon delivery by
Landlord of the then outstanding Letter of Credit.

     (e) For so long as no default has occurred under the Lease (and no event
has occurred or condition exists which with notice and/or passage of time would
give rise to such default), on each anniversary of the Commencement Date, the
amount of the Letter of Credit shall be reduced by 20% of the initial Letter of
Credit amount. Such reduction of the Letter of Credit shall not affect the
amount of the cash Security Deposit held by Landlord under Section 4.

                               Exhibit E, Page 6
<PAGE>

                                   EXHIBIT F

                        APPROVED LETTER OF CREDIT FORM

[Letterhead of Issuing Bank]
[must be a Bank whose location, credit and practices Landlord has approved]

RE:   IRREVOCABLE COMMERCIAL LETTER OF CREDIT NO. _________

TO:   [Name of project owner] ("Landlord"), ____________________________________
__________________ [Landlord's address]

Gentlemen:

We hereby issue our Irrevocable Commercial Letter of Credit in your favor, for
the account of _____________________________ [name of tenant and type of entity
(e.g. "ABC Corporation, a California corporation")] ("Tenant"), in the amount of
______________________________ Dollars ($__________). This amount is available
to you on presentation of your sight draft drawn upon us referring to the above
letter of credit number, date and amount being drawn hereunder, accompanied by
the signed statement of you or your authorized agent, Cornerstone Properties
Limited Partnership dba Wilson Cornerstone Properties Limited Partnership, that
the amount drawn hereunder is being drawn pursuant to the terms of the
_______________ [title of lease document (e.g. Office Lease, Lease Agreement,
etc.)] dated as of __________, between Tenant, as tenant, and Landlord, as
landlord, for certain premises located at __________________________ (the
"Lease").

Any draft presented for payment must be presented on or before ________________
[term should be at least one year], the date this Letter of Credit expires.
Partial drawings are permitted.

If you sell or otherwise transfer any interest in the "Building" (as defined in
the Lease), in the land upon which the same is located, in the Lease, or in
Landlord (including consolidations, mergers or other entity changes), you shall
have the right to transfer this Letter of Credit to your transferee(s),
successors or assigns.

We hereby certify that this is an unconditional and irrevocable Letter of Credit
and agree that a draft drawn under and in compliance with the terms hereof will
be honored upon presentation at our office at [Boston or New York].

This Letter of Credit shall automatically be extended and renewed for successive
one year periods at the end of the stated expiration date and each anniversary
thereof unless we notify you in writing, no later than forty-five (45) days
prior to the then applicable expiration date, that we will not extend and renew
the Letter of Credit for another one year term.

                               Exhibit F, Page 1
<PAGE>

Except to the extent inconsistent with the express provisions hereof, this
Letter of Credit is subject to and governed by Uniform Customs and Practice for
Documentary Credits (1993 Revision) International Chamber of Commerce
publication number 500.

                                              [Name of Bank]

                                      ---------------------------------
                                             Authorized Signature

                               Exhibit F, Page 2

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