Document:

<PAGE>
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                                                   EXHIBIT 10.16

                                      [*]

                                  DEED OF LEASE
                                       FOR
                                 WAREHOUSE SPACE

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
ARTICLE                                                                     PAGE
<S>                                                                         <C>
1.  DEFINITIONS.............................................................   1
2.  TERM....................................................................   6
3.  CONDITIONS OF PREMISES..................................................   7
4.  RENT....................................................................   8
5.  ADDITIONAL RENT.........................................................  10
6.  USE.....................................................................  11
7.  CARE OF PREMISES........................................................  12
8.  ALTERATIONS BY TENANT...................................................  12
9.  EQUIPMENT...............................................................  13
10.  OWNERSHIP AND REMOVAL OF PROPERTY......................................  13
11.  LANDLORD'S ACCESS TO PREMISES..........................................  14
12.  SERVICES AND UTILITIES.................................................  15
13.  RULES AND REGULATIONS..................................................  16
14.  REPAIR OF DAMAGE CAUSED BY TENANT: INDEMNIFICATION.....................  16
15.  LIMITATION ON LANDLORD LIABILITY.......................................  17
16.  FIRE AND OTHER CASUALTY................................................  17
17.  TENANT INSURANCE.......................................................  18
18.  CONDEMNATION...........................................................  20
19.  DEFAULT................................................................  21
20.  NO WAIVER..............................................................  24
21.  HOLDING OVER...........................................................  25
22.  SUBORDINATION..........................................................  25
23.  ASSIGNMENT AND SUBLETTING..............................................  26
24.  TRANSFER BY LANDLORD...................................................  28
25.  INABILITY TO PERFORM...................................................  29
26.  ESTOPPEL CERTIFICATES..................................................  29
27.  COVENANT OF QUIET ENJOYMENT............................................  29
28.  WAIVER OF JURY TRIAL...................................................  29
29.  BROKERS................................................................  30
30.  CERTAIN RIGHTS RESERVED BY LANDLORD....................................  30
31.  NOTICES................................................................  31
32.  MISCELLANEOUS PROVISIONS...............................................  31
</TABLE>

*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                       i
<PAGE>

<TABLE>
<S>                                                                           <C>
         A.  Benefit and Burden.............................................  31
         B.  Governing Law..................................................  31
         C.  No Partnership.................................................  31
         D.  Delegation by Landlord.........................................  32
         E.  Tenant Responsibility for Agents...............................  32
         F.  Invalidity of Particular Provisions............................  32
         G.  Counterparts...................................................  32
         H.  Entire Agreement...............................................  32
         J.  Mortgagee's Performance........................................  32
         K.  Limitation on Interest.........................................  32
         L.  Remedies Cumulative............................................  33
         M.  Annual Financial Statements....................................  33
33.  LENDER APPROVAL [Intentionally omitted.]...............................  33
34.  PARKING................................................................  33
35.  SECURITY DEPOSIT.......................................................  33
36.  HAZARDOUS MATERIALS....................................................  35
37.  RELOCATION OF TENANT [Intentionally omitted.]..........................  36
38.  MEMORANDUM OF LEASE....................................................  36
39.  ANTENNA LICENSE........................................................  37
40.  OPTIONS TO EXTEND......................................................  38
SIGNATURES..................................................................  41
</TABLE>

Exhibit A - Premises Plan
Exhibit B - Declaration of Acceptance
Exhibit C-1 - Cold Dark Shell Condition Specifications
Exhibit C-2 - Construction Schedule
Exhibit D-1 - Rules and Regulations
Exhibit D-2 - Declaration of Protective Covenants [*]
Exhibit E - Parking
Exhibit F - Description of the Land
Exhibit G - Special Tenant Requirements
Exhibit H - Tenant's Financial Statement
Exhibit I - Form of Memorandum of Lease
Exhibit J - Form of Nondisclosure Agreement

*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.
                                      ii

<PAGE>

                                      [*]

                                  DEED OF LEASE

          THIS DEED OF LEASE (the "Lease") is made and entered into this 15/th/
day of December, 1999, by and between TRIZECHAHN CENTERS, INC. dba TRIZECHAHN
BEAUMEADE CORPORATE MANAGEMENT, a California corporation ("Landlord") and
EQUINIX, INC., a Delaware corporation ("Tenant").

          In consideration of the Rent hereinafter reserved and the agreements
hereinafter set forth, Landlord and Tenant mutually agree as follows:

          1.   DEFINITIONS.

          Except as otherwise expressly provided or unless the context otherwise
requires, the following terms shall have the meanings assigned to them in this
Section:

               A. Alterations: Any improvements, alterations, fixed decorations
or modifications, structural or otherwise, to the Premises, the Building or the
Land, as defined below, including but not limited to the installation or
modification of carpeting, partitions, counters, doors, air conditioning ducts,
plumbing, piping, lighting fixtures, wiring, hardware, locks, ceilings and
window and wall coverings.

               B. Building: The building located on [*] in Ashburn, Virginia, in
the Park (as hereinafter defined) in which the Premises are located. Except as
expressly indicated otherwise, the term "Building" shall include all portions of
said building, including but not limited to the Premises and the common areas of
said building .

               C. Consumer Price Index (Regular and Base):  [Intentionally
omitted.]

               D. Default Rate: That rate of interest which is two (2)
percentage points above the annual rate of interest which is publicly announced
by Bank of America or its successor entity, if applicable ("Bank of America"),
from time to time as its "prime" rate of interest, irrespective of whether such
rate is the lowest rate of interest charged by Bank of America to commercial
borrowers. In the event that Bank of America ceases to announce such a prime
rate of interest, Landlord, in Landlord's reasonable discretion, shall designate
the prime rate of interest by another bank located in the Washington, D.C.
metropolitan area, which shall be the prime rate of interest used to calculate
the default rate.

               E. Fiscal Year: Each consecutive twelve (12) month period during
the Term of this Lease that commences on January 1 and concludes on December 31
inclusive.

               F. Ground Leases: All ground and other underlying leases from
which Landlord's title to the Land and/or the Building is or may in the future
be derived.

*CONFIDENTIAL TREATMENT REQUESTED.  CONFIDENTIAL PORTIONS HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.
                                       1
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"Ground Lessors" shall denote those persons and entities holding such ground or
underlying leases.

               G. Holidays: New Year's Day, Presidents' Day, Martin Luther King,
Jr.'s Birthday, Memorial Day, Independence Day, Labor Day, Columbus Day,
Veteran's Day, Thanksgiving Day, Christmas Day and any other holidays designated
by an executive order of the President of the United States or by Act of
Congress.

               H. Land: The real estate that supports the Building as more
fully described on Exhibit F attached hereto and made a part hereof, and all
associated easements.

               I. Park Common Areas: All areas, improvements, facilities and
equipment from time to time designated by Landlord for the common use or benefit
of Tenant, other tenants of the Building or the Park and their agents,
including, without limitation, roadways, entrances and exits, landscaped areas,
open areas, park areas, exterior lighting, service drives, loading areas,
pedestrian walkways, sidewalks, atriums, courtyards, concourses, stairs, ramps,
washrooms, maintenance and utility rooms and closets, exterior utility lines,
hallways, lobbies, elevators and their housing and rooms, common window areas,
common walls, common ceilings, common trash areas and parking facilities.

               J. Landlord's Work: All work to be performed by Landlord as set
forth on Exhibit C-1 attached hereto and made a part hereof.

               K. Lease Commencement Date: The date this Lease commences, as
determined pursuant to Subsection 2.A. below.

               L. Lease Year: That period of twelve (12) consecutive calendar
months that commences on the first day of the calendar month in which the Lease
Commencement Date occurs, and each consecutive twelve (12) month period
thereafter. The earliest such twelve (12) month period shall be referred to as
the "first Lease Year," and each of the following Lease Years shall similarly be
numbered for identification purposes.

               M. Mortgages: All mortgages, deeds of trust and similar security
instruments which may now or in the future encumber or otherwise affect the
Building or the Land, including mortgages related to both construction and
permanent financing. "Mortgagees" shall denote those persons and entities
holding such mortgages, deeds of trust and similar security instruments.

               N. Park Common Area Maintenance Expenses: All costs and expenses
incurred by Landlord during any Fiscal Year in owning, managing, operating and
maintaining the Park Common Areas, as determined by Landlord in accordance with
an accounting system established and regularly applied by Landlord. Such costs
and expenses shall include, but not be limited to the cost of insurance for the
Budding and the Park; labor costs (including social security taxes and
contributions and fringe benefits); charges under maintenance and service
contracts (including but not limited to chillers, boilers, elevators, window and
security services); the cost of water, gas, sanitary sewer, storm sewer,
electricity, and other utilities to Park Common Areas; the cost of services to
Park Common Areas and facilities and systems related thereto (including but not
limited to, paving and parking areas,

                                       2
<PAGE>

lighting and sound facilities, storm and sanitary drainage systems, utility
conduits, systems and ducts, fire protection systems, sprinkler systems,
security systems, Building signs, whether or not located on the Land, retaining
walls, curbs, gutters, fences, sidewalks, canopies, steps, ramps, grass, trees
and shrubbery), which services may include, among other things, ice and snow
removal, lighting, cleaning, landscaping, gardening, sweeping, painting, and
resurfacing; that portion of management fees which does not exceed three percent
(3%) of the aggregate gross revenues received by Landlord from the Park from all
sources; business taxes, license fees, public space and vault rentals and
charges; assessments imposed by any association now or hereafter established to
maintain the Park Common Areas (including, but not limited to, assessments
imposed by any association with respect to the Park); and the cost of any
equipment or services provided by Landlord in connection with the servicing,
operation, maintenance repair and protection of the Park Common Areas and
related exterior appurtenances (whether or not provided on the Lease
Commencement Date). Park Common Area Maintenance Expenses shall include the cost
of capital improvements made by Landlord to manage, operate or maintain the Park
Common Areas together with any financing charges incurred in connection
therewith, provided that such costs shall be amortized over the useful life of
the improvements and only the portion attributable to the Fiscal Year shall be
included in Park Common Area Maintenance Expenses for the Fiscal Year; further
provided, that such expenditures shall be (a) limited to those replacements of
Park components (other than buildings) with other Park components (other than
buildings) which serve similar purposes and which are reasonably necessary to
keep the Park in good repair, in Landlord's reasonable judgment, and which will
not change the character of the Park, (b) improvements or Park components (other
than buildings) added to the Park which in Landlord's reasonable Judgment will
increase the efficiency the Park (i.e., are reasonably anticipated by Landlord
to reduce Park Common Area Maintenance Expenses as they relate to the item which
is the subject of the capital expenditure or to reduce the rate of increase in
the Park Common Area Maintenance Expense which relates to the item which is the
subject of the capital expenditure from what it otherwise may have been
reasonably anticipated to be in the absence of such capital expenditure), and
(c) improvements or replacements which are required to comply with the
requirements of any laws, regulations or insurance or utility company
requirements, except for conditions existing in violation thereof on the Lease
Commencement Date. Common Area Maintenance Expenses shall not include (i) Real
Estate Tax Expenses, (ii) payments of principal and interest on any Mortgages,
(iii) leasing commissions, (iv) costs of preparing, improving or altering any
spaces in preparation for occupancy of any new or renewal tenant, (v) costs
incurred by Landlord on account of utilities, char services or other services
attributable to space occupied by any tenant of the Building, (vi) the cost of
damage and repairs necessitated by the gross negligence or willful misconduct of
Landlord or of Landlord's agents and employees, (vii) any cost or expense
incurred by reason of the remediation or clean-up of any contamination of the
Building, the Land or the Park, or the soils or ground water underlying the
Building, the Land or the Park, by hazardous materials or toxic substances to
the extent that either (A) such contamination existed prior to the Lease
Commencement Date and was not caused by Tenant or any of its employees, agents
or contractors, or (B) such contamination arose on or after the Lease
Commencement Date and was caused by any other tenant of the Park or by Landlord
or any of its employees, agents or contractors, (viii) overhead costs and profit
increment paid to subsidiaries or affiliates of Landlord for services on or for
the Building, the Land or the Park, to the extent only that the cost of such
services exceed the competitive costs of such services were they not so rendered
by a subsidiary or affiliate of Landlord, (ix) any

                                       3
<PAGE>

deductible on Landlord's insurance policy in excess of Fifty Thousand Dollars
($50,000,00), (x) the costs, including permit, license and inspection costs,
incurred with respect to the construction of the Building, (xi) the cost of any
services provided to other tenants of the Park which are not made available to
Tenant, (xii) legal fees, brokerage commissions, advertising costs, or other
related expenses incurred in connection with the leasing of the Building or the
Park or associated with monetary disputes with tenants or other occupants of the
Building or the Park or with the enforcement of any monetary provision of any
lease or defense of Landlord's title to or interest in the Budding or the Park
or any part thereof, (xiii) except to the extent allocable to the Park, salaries
of personnel to the extent that such personnel perform services other than in
connection with the management, operation, repair or maintenance of the
Building, the Land or the Park, and (xiv) Landlord's general corporate overhead
and general and administrative expenses not related to the Building, the Land or
the Park.

               O. Park: That certain business park located in Ashburn, Virginia
known as [*] which as of the date of this Lease contains approximately [*]
rentable square feet in five (5) buildings, known as 21731, 21721, 21711, 21701,
and the Building (with an address to be determined).

               P. Premises: [*] square feet of rentable area comprising the
entirety of the Building, including, but not limited to, the roof of the
Building as shown on the floor plan attached hereto as Exhibit A. However, the
area and plan of the Premises may change in the event of the exercise of any
option to expand or contract the Premises set forth in this Lease. The rentable
area of the Premises has been determined in accordance with the Greater
Washington Commercial Association of REALTORS(R) Standard Method of Measurement
dated June 13, 1995 (the "GWCAR Standard Method of Measurement"). Tenant shall
have the option, exercisable by written notice to Landlord within thirty (30)
days following the Lease Commencement Date, to verify the rentable area of the
Premises by having the Premises remeasured by Tenant's architect in the manner
provided for in the GWCAR Standard Method of Measurement (the Tenant's
Remeasurement"). If the rentable area of the Premises resulting from the
Tenant's Remeasurement is within two percent (2%) of the rentable area of the
Premises as stated above (the Stated Area ), the rentable area of the Premises
shall be equal to the Stated Area. If the Tenant's Remeasurement is not within
two percent (2%) of the Stated Area, Landlord and Tenant shall negotiate in good
faith for ten (10) days to attempt to reach agreement as to the rentable area of
the Premises. If within such 10-day period the parties have not mutually agreed
on the rentable area of the Premises, then within five (5) days following) such
10-day period Landlord s architect and Tenant's architect shall jointly appoint
a third architect. The third architect shall independently make his
determination of the rentable area of the Premises within ten (10) days after
his appointment. The highest and the lowest measurements among the three (3)
architects shall be disregarded and the remaining determination shall be deemed
to be the rentable area of the Premises. Each party shall pay for the cost of
its architect and one-half of the cost of the third architect. In the event that
Landlord's architect and Tenant's architect do not agree on a third architect
within such 10-day period, the dispute shall be resolved by arbitration in
accordance with the then prevailing Commercial Rules of the American Arbitration
Association. For purposes of this Section 1.P., an "architect" shall mean an
architect certified by The American Institute of Architects and licensed or
registered to practice architecture in the Commonwealth of Virginia.

*CONFIDENTIAL TREATMENT REQUESTED.  CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.
                                       4
<PAGE>

          If the rentable area of the Premises as determined above is not within
two percent (2%) of the Stated Area, then within fifteen (15) days after final
determination of the rentable area of the Premises, Landlord shall prepare, and
Landlord and Tenant shall each promptly execute, an amendment to this Lease
pursuant to which the Base Rent, Tenant's Share of Park Common Area Maintenance
Expenses and Tenant's Share of Real Estate Tax Expenses and any other affected
provisions of this Lease are recalculated to reflect such increase or decrease
in the rentable area of the Premises, which amendment shall be effective
retroactive to the Lease Commencement Date.

               Q. Premises' Standard Electrical Capacity: [Intentionally
omitted.]

               R. Real Estate Tax Expenses: All taxes and assessments, general
or special, ordinary or extraordinary, and foreseen or unforeseen, that are
assessed, levied or imposed upon the Park, including, but not limited to, the
Building and the Land, under any current or future taxation or assessment system
or modification of, or supplement or substitute for, such system, whether or not
based on or measured by the receipts or revenues from the Park Building or and
the Land (including all taxes and assessments for public improvements or any
other purpose and any gross receipts or similar taxes). Real Estate Tax Expenses
also shall include all reasonable expenses incurred by Landlord in obtaining or
attempting to obtain a reduction of any such taxes, rates or assessments,
including but not limited to legal fees, but shall not include any taxes on
Tenant's Personal Property or other tenants personal property, which taxes are
the sole obligation of each tenant.

               S. Rent: All Base Rent and Additional Rent.

                    (1) Base Rent:  The amount payable by Tenant pursuant to
Subsection 4.A. below.

                    (2) Additional Rent:  All sums of money payable by Tenant
pursuant to this Lease other than Base Rent.

                    (3) Monthly Rent: A monthly installment of Base Rent and
Additional Rent, if any, which shall equal one-twelfth (1/12th) of Base Rent and
Additional Rent then in effect.

               T. Tenant's Personal Property: All Alterations, equipment,
improvements, furnishings and/or other property now or hereafter installed or
placed in or on the Premises by and at the sole expense of Tenant or with
Tenant's permission (other than any property of Landlord), with respect to which
Tenant has not been granted any credit or allowance by Landlord, and which: (i)
is removable without damage to the Premises, the Building and the Land, unless
such damage is repaired by Tenant at its sole cost and expense, and (ii) is not
a replacement of any property of Landlord, whether such replacement is made at
Tenant's expense or otherwise.

               U. Tenant's Share:

                    (1) Tenant's Share of Park Common Area Maintenance Expenses
shall be that percentage of Park Common Area Maintenance Expenses which is equal

                                       5
<PAGE>

to the number of square feet of rentable area in the Premises divided by the
total number of square feet of rentable area in the Park ([*] on the Lease
Commencement Date). As of the Lease Commencement Date, Tenant's Share of Park
Common Area Maintenance Expenses shall be [*] percent ([*]).

                    (2) Tenant's Share of Real Estate Tax Expenses shall be that
percentage of Real Estate Tax Expenses which is equal to the number of square
feet of rentable area in the Premises divided by the total number of square feet
of rentable area in the Building Park ([*] on the Lease Commencement Date).
As of the Lease Commencement Date, Tenant's Share of Real Estate Tax Expenses
shall be [*] percent ([*]).

                    (3) Tenant's Share of Park Common Area Maintenance Expenses
and Tenant's Share of Real Estate Tax Expenses shall change any time the number
of square feet of rentable area leased hereunder by Tenant or the number of
square feet of rentable area in the Park increases or decreases.

               V. Unavoidable Delay: Any delays due to strikes, labor disputes,
shortages of material, labor or energy, acts of God, governmental restrictions,
enemy action, civil commotion, fire, unavoidable casualty or any other causes
beyond the control of Landlord.

               W.   Work Agreement:  [Intentionally omitted.]

          2.   TERM.

               A. Term of Lease: The term of this Lease (the "Term") shall
commence on a date (the "Lease Commencement Date"), as defined below, and shall
terminate at midnight on the day which is the tenth (10th) anniversary of the
Lease Commencement Date, or such earlier date on which this Lease is terminated
pursuant to the provisions hereof (the "Lease Expiration Date"). The Lease
Commencement Date shall be that date on which Landlord notifies Tenant that the
Premises is in a "substantially complete" Cold Dark Shell Condition (as
hereinafter defined), as certified by Landlord's architect based upon practices
as are detailed by The American Institute of Architects. Landlord hereby leases
the Premises to Tenant and Tenant hereby leases the Premises from Landlord for
the Term.

          Landlord shall use reasonable efforts to substantially complete
Landlord's Work in accordance with the schedule set forth on Exhibit C-2 which
is attached hereto and made a part hereof (the "Construction Schedule") on or
before May 31, 2000. However, Landlord shall in no event be liable or subject to
any claim for failure to substantially complete Landlord's Work by such date or
for delay or inability to deliver possession of the Premises to Tenant for any
reason. Notwithstanding anything contained herein to the contrary, if Landlord
shall be delayed in substantially completing Landlord's Work as a result of:

                    (a) Tenant's failure to furnish to Landlord, on or before
the dates and time periods set forth in the Construction Schedule, the
information, requirements and/or approvals for any work to be done hereunder;

*CONFIDENTIAL TREATMENT REQUESTED.  CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.
                                       6
<PAGE>

                    (b) Tenant's request for changes in any plans subsequent to
the date(s) set forth for such approval in the Construction Schedule;

                    (c) Tenant's failure to approve the plans, specifications or
cost estimates for Additional Tenant Work (as hereinafter defined) or make any
payment within the time required under Section 3 hereof;

                    (d) Tenant's request for materials, finishes or
installations other than Landlord's Park standard;

                    (e) The result of Tenant's or its agents' or employees'
acts, failure to act, or failure to act in a timely manner;

                    (f) Landlord's provision for Tenant's contractor to commence
Tenant's initial buildout of the Premises prior to completion of Landlord's Work
pursuant to the Cold Dark Shell Specifications; or

                    (g) Delays caused by coordination of Additional Tenant Work
and delivery of the Cold Dark Shell Specifications;

then, solely for the purposes of determining the commencement date of Tenant's
liability for Base Rent and other charges under this Lease, such delay shall
neither postpone the Lease Commencement Date nor the date of substantial
completion by Landlord of the Premises.

               B. Declarations: If requested by Landlord at any time during the
Term, Tenant promptly will execute a declaration in the form attached hereto as
Exhibit B.

               C. Effective Date: The rights and obligations set forth in this
Lease, except for the obligation to pay Rent and as otherwise specifically
provided herein to the contrary, shall become effective on the date of final
execution of this Lease.

          3.   CONDITIONS OF PREMISES.

          Landlord shall deliver the Premises to Tenant in a "Cold Dark Shell
Condition", which shall be in accordance with the specifications set forth on
Exhibit C-1 (the "Cold Dark Shell Specifications"). Landlord and Tenant shall
each use diligent efforts to fulfill their respective obligations necessary to
achieve the construction dates set forth on the Construction Schedule. Except as
set forth in Exhibit C attached hereto, Landlord shall have no obligation to
make any improvements or alterations to the Premises.

          If Tenant shall desire any work to be performed by Landlord in the
Premises, other than Landlord's Work, that is, any work not contained in the
Cold Dark Shell Specifications ("Additional Tenant Work"), then (i) such
Additional Tenant Work shall be subject to Landlord's sole and absolute
discretion, (ii) Landlord shall cooperate with Tenant in order to obtain the
approval of the [*] Owners Association, Inc. (the "Beaumeade Association") with
respect to Additional Tenant Work, if such approval is required pursuant to
Section 8.A. hereof, and (iii) all Additional Tenant Work shall be performed at
Tenant's sole cost and expense, including, but not limited to, the costs
incurred by Landlord

*CONFIDENTIAL TREATMENT REQUESTED.  CONFIDENTIAL PORTIONS HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.
                                       7
<PAGE>

relating to attempts to obtain the approval of such Additional Tenant Work by
the Beaumeade Association. If any, Tenant shall pay the full amount of the costs
thereof to Landlord, as Additional Rent hereunder, as follows: Not later than
three (3) business days following Tenant's receipt from Landlord of written
notice of the cost of the Additional Tenant Work (the "Additional Tenant Work
Cost"), Tenant shall deposit in escrow with Commercial Settlements, Inc. ("CSI")
the full amount of the Additional Tenant Work Cost as set forth in Landlord's
notice. Such amount deposited in escrow, or such lesser amount as remains
therein after disbursements therefrom, is hereinafter referred to as the
"Additional Tenant Work Cost Escrow". At each time that a portion of the
Additional Tenant Work has been substantially completed, Landlord shall have the
right to request from Tenant that Tenant authorize the disbursement from the
Additional Tenant Work Cost Escrow of such portion of the Additional Tenant Work
Cost as is allocable to such portion of the Additional Tenant Work, which
request shall be made in writing and accompanied by copies of the relevant
disbursement request from the contractor(s) or supplier(s) requesting such
disbursement. Within three (3) business days following receipt of Landlord's
request for approval by Tenant of a disbursement from the Additional Tenant Work
Cost Escrow, Tenant shall either notify Landlord of any objections thereto or
approve such request in writing, which approval shall not be unreasonably
withheld, conditioned or delayed. In the event that Tenant does not approve a
disbursement request, CSI shall not disburse the funds to Landlord, and Tenant
shall indemnify Landlord against, and hold Landlord harmless from, any and all
losses, costs, damages, liabilities, claims of action and expenses (including,
but not limited to, late charges, penalties, reasonable costs and reasonable
attorneys' fees) incurred by Landlord as a result, direct or indirect, of
Tenant's failure to timely approve a disbursement request. The Additional Tenant
Work Cost Escrow shall be disbursed in not more than six (6) payments therefrom.

          4.   RENT.

          From and after the Lease Commencement Date, Tenant shall pay to
Landlord such Base Rent and Additional Rent as set forth in this Section 4 and
in Section 5 below.

               A.   Base Rent:  Base Rent shall equal:  The following amounts:

<TABLE>
<CAPTION>
                     Base Rent Per
                    Square Foot Per         Base Rent Per            Monthly Base
 Lease Year              Annum                  Annum                    Rent
------------       -----------------       ----------------         --------------
<S>                 <C>                     <C>                      <C>
     1                   $ [*]                  $ [*]                   $ [*]
     2                   $ [*]                  $ [*]                   $ [*]
     3                   $ [*]                  $ [*]                   $ [*]
     4                   $ [*]                  $ [*]                   $ [*]
     5                   $ [*]                  $ [*]                   $ [*]
     6                   $ [*]                  $ [*]                   $ [*]
     7                   $ [*]                  $ [*]                   $ [*]
     8                   $ [*]                  $ [*]                   $ [*]
     9                   $ [*]                  $ [*]                   $ [*]
    10                   $ [*]                  $ [*]                   $ [*]

</TABLE>

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                       8
<PAGE>

Tenant shall pay Base Rent to Landlord in equal monthly installments ("Monthly
Base Rent") in advance on the first day of each calendar month during the Term,
without notice, except that the first monthly installment of Base Rent shall be
paid upon execution of this Lease. If the Lease Commencement Date occurs on a
date other than the first day of a calendar month, Tenant shall receive a credit
equal to the Monthly Base Rent multiplied by the number of days in said calendar
month prior to the Lease Commencement Date and divided by the number of days in
such month, which credit shall be applied toward the installment of Monthly Base
Rent next due hereunder. If the Lease Expiration Date occurs after the
expiration of the last numbered Lease Year set forth above in this Section 4.A.
for which an amount of Monthly Base Rent is specified, then Monthly Base Rent
shall continue to be payable by Tenant at such rate for each month or portion of
a month thereafter which is prior to the Lease Expiration Date.

               B. Payment: All Base Rent and Additional Rent due and payable to
Landlord under this Lease shall be made payable to TrizecHahn Centers, Inc. dba
TrizecHahn Beaumeade Corporate Management and delivered to TrizecHahn Centers,
Inc. dba TrizecHahn Beaumeade Corporate Management at Bank of America, P.O. Box
#631577, Baltimore, MD 21263-1577.

               C. Late Fee: If Tenant fails to make any payment of Rent on or
before the date when payment is due, then Tenant also shall pay to Landlord a
late fee equal to five percent (5%) of the amount that is past due for each
month or part thereof until such Rent is fully paid; provided, however, that,
if, during each of the first three (3) Lease Years, Tenant has made all payments
of Rent on or before the date when such payments are due and payable hereunder,
then, commencing on the first day of the fourth (4th) Lease Year and continuing
for the remainder of the Term, in lieu of the foregoing, the late fee provided
for in this Section 3.C. shall not be assessed unless Tenant falls to make full
payment of Rent within five (5) days after the day on which such payment is due.
Said late fee shall be deemed reimbursement to Landlord for its costs of
carrying and processing Tenant's delinquent account. Acceptance by Landlord of
said late fee shall not waive or release any other rights or remedies to which
Landlord may be entitled on account of such late payment.

               D. Arbitration: Any statement provided to Tenant by Landlord
pursuant to Section 5 below shall be conclusive and binding upon Tenant unless,
within thirty (30) days after receipt thereof, Tenant notifies Landlord of the
respects in which the statement is claimed to be incorrect. Unless otherwise
mutually agreed, any such dispute shall be determined by arbitration in the
jurisdiction in which the Premises are located, in accordance with the then
current commercial rules of the American Arbitration Association. The costs of
the arbitration shall be divided equally between Landlord and Tenant, except
that each party shall bear the cost of its own legal fees, unless (i) the
arbitration results in a determination that Landlord's statement contained a
discrepancy of less than five percent (5%) in Landlord s favor in which event
Tenant shall bear all costs incurred in connection with such arbitration
including without limitation reasonable legal fees or (ii) the arbitration
results in a determination that Landlord's statement contained a discrepancy of
at least five percent (5%) in Landlord's favor, in which event Landlord shall
bear all costs incurred in connection with such arbitration, including, without
limitation, reasonable legal fees. Pending determination of any dispute Tenant
shall pay all amounts due pursuant to the disputed statement but such payments
shall be without prejudice to Tenant's position. Upon at least fifteen (15) days
notice to Landlord,

                                       9
<PAGE>

Tenant shall have reasonable access during normal business hours and at Tenant's
expense to appropriate books and records of Landlord relating to the amount of
expenses covered by the disputed statement for the purpose of verifying the
statement. Any such review shall be made only by Tenant's employees and/or by an
auditor hired by Tenant who is a Certified Public Accountant and who is employed
on other than a contingent fee basis.

          5.   ADDITIONAL RENT.

               A.   To Cover Consumer Price Index Increases: [Intentionally
omitted.]

               B.   To Cover Park Common Area Maintenance Expenses and Real
Estate Tax Expenses: In addition to all other Rent set forth herein for each
Fiscal Year Tenant shall pay to Landlord as Additional Rent an amount equal to
the sum of Tenant's Share of Park Common Area Maintenance Expenses and Tenant's
Share of Real Estate Tax Expenses; provided, however, that for the Fiscal Years
during which the Term begins and ends, Tenant's Share of the aforesaid sum shall
be prorated based upon the greater of: (i) the number of days during such Fiscal
Year that this Lease is in effect or (ii) the number of days that Tenant
actually occupies the Premises or any portion thereof.

               C.   Statements:

                    (1)  [Intentionally omitted.]

                    (2)  For each Fiscal Year Landlord shall deliver to Tenant a
statement estimating Tenant's Share of Park Common Area Maintenance Expenses and
Tenant's Share of Real Estate Tax Expenses for such Fiscal Year, which Tenant
shall pay in equal monthly installments in advance on the first day of each
calendar month during each Fiscal Year. Tenant shall continue to pay such
estimated Tenant's Share of Park Common Area Maintenance Expenses and Tenant's
Share of Real Estate Tax Expenses until Tenant receives the next such statement
from Landlord at which time Tenant shall commence making monthly payments
pursuant to Landlord s new statement. With the first payment of Monthly Base
Rent which is due at least fifteen (15) days after Tenant's receipt of a
statement from Landlord specifying estimated Tenant's Share of Park Common Area
Maintenance Expenses and Tenant's Share of Real Estate Tax Expenses payable
during the Fiscal Year Tenant shall pay the difference between its monthly share
of such sums for the preceding months of the Fiscal Year and the monthly
installments which Tenant has actually paid for said preceding months.

               D. Retroactive Adjustments: After the end of each Fiscal Year
Landlord shall determine and shall provide to Tenant a statement of Tenant's
Share of Park Common Area Maintenance Expenses and Tenant's Share of Real Estate
Tax Expenses for the Fiscal Year. Within thirty (30) days after delivery of any
such statement Tenant shall pay to Landlord any deficiency between the amount
shown as Tenant's Share of Park Common Area Maintenance Expenses and Tenant's
Share of Real Estate Tax Expenses for the Fiscal Year and the estimated payments
made by Tenant. Tenant shall be credited with any excess estimated payments
toward payments by Tenant of the share of estimated Tenant's Share of Park
Common Area Maintenance Expenses and Tenant's Share of Real Estate Tax Expenses
or if the Term has expired Landlord shall refund such amount to Tenant within
thirty (30) days following the date

                                       10
<PAGE>

of issuance of Landlord s statement provided that Tenant is not then in default
under this Lease or if Tenant is then in default under this Lease such refund
shall be made within thirty (30) days following the date that such default is
cured.

               E. Change In or Contest of Taxes: In the event of any change by
any taxing body in the period or manner in which any of the Real Estate Tax
Expenses are levied assessed or imposed Landlord shall have the right in its
sole discretion to make appropriate adjustments with respect to computing
increases in Real Estate Tax Expenses. Real Estate Tax Expenses which are being
contested by Landlord shall be included in computing Tenant's Share of Real
Estate Tax Expenses under this Section but if Tenant shall have paid Rent on
account of contested Real Estate Tax Expenses and Landlord thereafter receives a
refund of such taxes Tenant shall receive a credit toward subsequent estimated
payments in an amount equal to Tenant's Share of such refund.

               F. Sales, Use or Other Taxes: If during the Term any governmental
authority having jurisdiction over the Building or the Land levies assesses or
imposes any tax on Landlord the Premises the Building the Land or the Rent
payable hereunder in the nature of a sales tax use tax or any tax except (i)
taxes on Landlord s income (ii) estate or inheritance taxes or (iii) Real Estate
Tax Expenses then Tenant shall pay its proportionate share to Landlord within
fifteen (15) days after receipt by Tenant of notice of the amount of such tax.

          6.   USE.

               A. Permitted Use: Tenant shall use and occupy the Premises solely
for general office use and as a telecommunications service center with related
legal uses and for no other purpose.

               B. Legal and Other Restrictions of Tenant's Use: In its use of
the Premises, Tenant shall comply with all present and future laws regulations
(including but not limited to fire and zoning regulations) and ordinances of all
other public and quasi-public agencies having Jurisdiction over the Land or the
Building. Tenant shall not use the Park the Land, the Building or use or occupy
the Premises for any unlawful disorderly or hazardous purposes or in a manner
which will interfere with the rights of Landlord other tenants or their invitees
or in any way injure or annoy any of them; Landlord acknowledges that Tenant's
permitted uses as set forth in Section 6.A. above which are in accordance with
the provisions of this Lease and all applicable laws and governmental
regulations shall not be deemed to cause such interference. Notwithstanding the
foregoing Tenant shall not be responsible for (i) any such noncompilance of the
Cold Dark Shell Condition existing on the Lease Commencement Date (ii) making
any Alterations to the Premises except to the extent that such Alterations are
required either due to Tenant's particular use of the Premises, due to
Alterations made by Tenant within the Premises or due to any requirements of
applicable law or any governmental requirements or (iii) any remediation of
Hazardous Materials (as hereinafter defined) except to the extent caused by
Tenant or any of its employees agents or contractors.

                                       11
<PAGE>

          7.   CARE OF PREMISES.

          Tenant shall at its expense keep the Premises (including all
improvements fixtures and other property located therein) in a neat and clean
condition and in good order and repair and will suffer no waste or injury
thereto. Tenant shall surrender the Premises at the end of the Term in as good
order and condition as they were in on the Lease Commencement Date ordinary wear
and tear excepted.

          8.   ALTERATIONS BY TENANT.

               A. Making of Alterations; Landlord's Consent; Beaumeade
Association's Consent: Tenant shall not make or permit to be made any
Alterations without the prior written consent of Landlord both as to whether the
Alterations may be made and as to how and when they will be made which consent
shall not be unreasonably withheld or delayed with respect to any proposed
Alteration which would not be visible from outside of the Premises nor affect
any of the structural components of the Building; provided however that the
consent of Landlord shall not be required for (i) painting or carpeting of the
Premises or (ii) Alterations costing less than Fifty Thousand Dollars ($50,000)
in the aggregate which are not visible from outside of the Premises and which do
not affect any of the structural components of the Building; further provided
that Tenant shall give Landlord at least ten (10) days prior written notice of
any such Alterations not requiring Landlord's consent and Tenant shall observe
all reasonable rules and regulations promulgated by Landlord with respect to the
performance of Alterations. Any Alterations shall be made at Tenant's expense by
its contractors and subcontractors and in accordance with complete plans and
specifications approved in advance in writing by Landlord and only after Tenant:
(i) has obtained all necessary permits from governmental authorities having
jurisdiction and has furnished copies thereof to Landlord, (ii) has submitted to
Landlord an architect's certificate that the Alterations will conform to all
applicable laws and regulations and (iii) has complied with all other
requirements reasonably imposed by Landlord including without limitation any
requirements due to the underwriting guidelines of Landlord s insurance
carriers. Landlord's consent to any Alternations and approval of any plans and
specifications constitutes approval of no more than the concept of these
Alterations and not a representation of warranty with respect to the quality or
functioning of such Alterations plans and specifications. Tenant shall be and is
solely responsible for the Alterations and for the proper integration thereof
with the Building the Building's systems and existing conditions. Landlord shall
have the right but not the obligation to supervise the making of any
Alterations, if any Alterations are made without the prior written consent of
Landlord or the Beaumeade Association, if applicable or which do not conform to
plans and specifications approved by Landlord or the Beaumeade Association if
applicable or to other conditions imposed by Landlord or the Beaumeade
Association if applicable and such nonconformity is not fully corrected by
Tenant within fifteen (15) days after notice from Landlord to Tenant or such
shorter notice period as Landlord in good faith reasonably believes to be
necessary in order to comply with the requirements of any applicable law
governmental regulation or insurance company requirement, then Landlord may in
its sole discretion correct or remove such Alterations at Tenant's expense.
Following completion of any Alterations at Landlord's request Tenant either
shall deliver to Landlord a complete set of "as built" plans showing the
Alterations or shall reimburse Landlord for any expense incurred by Landlord in
causing the Building plans to be modified to reflect the Alterations. In
addition to the foregoing, any Alterations which are visible from outside of the

                                       12
<PAGE>

Premises are subject to the prior review and approval of the Beaumeade
Association, which approval may be granted or denied in the sole and absolute
discretion of the Beaumeade Association, and which approval Tenant is solely
responsible for obtaining.

               B. No Liens: Tenant shall take all necessary steps to ensure that
no mechanic's or materialmen's liens are filed against the Premises, the
Building or the Land as a result of any Alterations made by the Tenant. If any
mechanic's lien is filed Tenant shall discharge the lien within ten (10) days
thereafter at Tenant's expense, by paying off or bonding the lien.

          9.   EQUIPMENT.

               A. Permitted Equipment: With the exception of the items of
equipment or machinery which are reflected on Tenant's plans for Tenant's
initial buildout of the Premises Tenant shall not install or operate in the
Premises any equipment or other machinery without: (i) obtaining the prior
written consent of Landlord who may condition its consent upon the payment by
Tenant of Additional Rent for additional wiring or other expenses resulting
therefrom, which consent shall not be unreasonably withheld, conditioned or
delayed, unless Landlord determines, in its sole and absolute discretion, that
such equipment or machinery causes noise or vibration which would disturb any
other tenant of the Park, (ii) securing all necessary permits from governmental
authorities and utility companies and furnishing copies thereof to Landlord, and
(iii) complying with all other requirements reasonably imposed by Landlord.
Tenant shall not install any equipment or machinery which may necessitate any
changes, replacements or additions to or material changes in the use of the
water systems of the Building without obtaining the prior written consent of
Landlord, who may withhold its consent in its absolute discretion.

               B.   Payment For Excess Utility Usage:  [Intentionally omitted.]

               C. Noise; Vibration; Floor Load: Business machines and equipment
belonging to Tenant, which cause noise or vibration that may be transmitted to
any part of the Building to such a degree as to be objectionable to Landlord or
to any tenant of the Park, shall be installed and maintained by Tenant at
Tenant's expense on devices that eliminate the noise and vibration. Tenant shall
not place any load upon the floor of the Premises which exceeds the per square
foot load the floor was designed to carry (it being understood and agreed that
the floor is a six inch (6") slab with a capacity of two hundred fifty (250)
pounds per square foot.

          10.  OWNERSHIP AND REMOVAL OF PROPERTY.

               A. Landlord's Property: Any Alterations, including, but not
limited to, Additional Tenant Work and Tenant's initial buildout of the
Premises, and other improvements and any equipment, machinery, furnishings and
other property, installed or located in the Premises, the Building or the Land
by or on behalf of Landlord or Tenant, except for Tenants Personal Property: (i)
shall immediately become the property of Landlord, and (ii) shall be surrendered
to Landlord with the Premises as a part thereof at the end of the Term;
provided, however, that if Landlord requests Tenant to remove any Alterations
installed by or on behalf of Tenant, Tenant shall cause the same to be removed
at Tenant's expense on or before

                                       13
<PAGE>

the Lease Expiration Date, or shall reimburse Landlord for the cost of such
removal, as elected by Landlord (unless Landlord expressly waives in writing the
right to require such removal at the time Landlord give its consent to the
making of such Alterations). Notwithstanding the foregoing, Tenant, upon
submitting its request to Landlord to make Alterations, including, but not
limited to, Additional Tenant Work, shall have the right to request therein that
Landlord specify whether and to what extent Landlord will require Tenant to
remove the Alterations in question at the end of the Term, provided that Tenant
refers therein to the provisions of this Section 10.A. If Tenant shall fail to
request such information in its request to make any Alterations, such right
shall be deemed null and void as to the Alterations in question, and all such
Alterations shall thereafter be subject to the exercise of Landlord's rights and
to Tenant's obligations set forth in the first sentence of this Section 10.A. If
Tenant submits its request for such information in accordance with the foregoing
provisions and Landlord consents to the Alterations requested, Landlord shall,
together with its consent, specify in writing whether and to what extent it will
require Tenant to remove the Alterations in question at the end of the Term, and
if Landlord falls so to specify, Tenant shall have no further obligation to
remove the Alterations which were the subject of Tenant's request.

               B. Removal of Property At End of Term: Tenant shall remove all of
Tenant's Personal Property, and all computer cabling and wiring installed by or
on behalf of Tenant (irrespective of whether such cabling and wiring constitutes
Tenant's Personal Property under the terms of this Lease, and at Tenant's
expense, using a contractor approved in advance by Landlord in writing), from
the Building and the Land on or before the Lease Expiration Date. Any personal
property belonging to Tenant or to any other person or entity which is left in
the Building or on the Land after the date this Lease is terminated for any
reason shall be deemed to have been abandoned. In such event, Landlord shall
have the right to store such property at Tenant's sole cost and/or to dispose of
it in whatever manner Landlord considers appropriate, without waiving its right
to claim from Tenant all expenses and damages caused by Tenant's failure to
remove such property, and Tenant and any other person or entity shall have no
right to compensation from or any other claim against Landlord as a result.

          11.  LANDLORD'S ACCESS TO PREMISES.

          Upon such notice as is reasonable under the circumstances (which
notice shall not be of less than forty-eight (48) hours, except in an emergency,
and which notice may be given orally), Landlord may at any reasonable time enter
the Premises to examine them to make alterations or repairs thereto or for any
other purposes which Landlord considers necessary or advisable; however in the
case of any emergency Landlord and its agents may enter the Premises at any time
and in any manner. Tenant shall allow the Premises to be exhibited by Landlord
upon such notice as is reasonable under the circumstances (which notice shall
not be of less than forty-eight (48) hours and which notice may be given
orally): (i) at any reasonable time to representatives of lending institutions
or to prospective purchasers of the Building, and (ii) at any reasonable time to
persons who may be interested in leasing the Premises during the last twelve
(12) months of the Term. Landlord reserves the right and shall be permitted
reasonable access to the Premises to install facilities within and through the
Premises and to install and service any systems deemed advisable by Landlord to
provide services or utilities to any tenant of the Building. Notwithstanding the
foregoing, Landlord shall not enter the Premises without being accompanied by a
representative of Tenant; provided, however, that, in consideration for

                                       14
<PAGE>

such right granted to Tenant by Landlord, (i) Tenant hereby authorizes Landlord
and any of its employees, agents and contractors to break any locks and the
doors and walls to which locks are attached, if Landlord deems such action
necessary, and to enter the Premises without accompaniment by Tenant's
representative (a) in the event of an emergency, if Tenant's representative is
not reached immediately, or (b) in the event of the need to make inspections,
repairs, maintenance or improvements and Tenant's failure to provide Landlord
access to the Premises when requested by Landlord pursuant to this Section 11,
and (ii) Tenant hereby indemnifies Landlord (including its shareholders,
partners, members, employees, agents and contractors) against and holds Landlord
(including its shareholders, partners, members, employees, agents and
contractors) harmless from, any and all liabilities, losses, damages, causes of
action, suits, claims, demands, judgments, costs and expenses of any kind
(including court costs and reasonable attorneys' fees) asserted against Landlord
by any third party relating to or arising from or in connection with Landlord's
exercise of its rights under this sentence.

          12.  SERVICES AND UTILITIES.

               A. Utilities Provided: Tenant will provide, at its expense, for
the separate metering of all utilities to be supplied to the Premises, and shall
contract directly with the appropriate public utility companies for the
supplying of all such utilities to the Premises. Tenant shall pay all submetered
utility charges to the appropriate utilities, as and when due. In the event the
Premises cannot be submetered for a particular utility, Landlord may, at its
option, cause a survey to be made by an independent electrical engineering or
consulting firm, at Tenant's expense, to measure Tenant's consumption of such
utility. For all utility consumption measured by survey, Tenant shall pay to
Landlord, as Additional Rent, all sums necessary to reimburse Landlord for its
costs of providing such utilities, within ten (10) days after Landlord submits
to Tenant any statement setting forth such costs. It is expressly understood
that, in the event Tenant is unable to have the Premises submetered for a
particular utility, in lieu of causing a survey to be done, Landlord shall have
the option to charge Tenant for its equitable share of the cost of such utility
to all non-submetered rentable areas in the Building.

               B. Right to Discontinue: [Intentionally Omitted.]

               C. No Liability: Except as otherwise specifically set forth
herein, Landlord shall have no liability to Tenant or others based on any
failure by Landlord to furnish any utilities and services to be furnished by
Landlord hereunder, due to Unavoidable Delays, repair or maintenance work or any
other reason, and such failure shall neither render Landlord liable for damages
to either person or property, nor be construed as an eviction of Tenant, nor
cause a diminution or abatement of Rent nor relieve Tenant of any of Tenant's
obligations hereunder.

               D. Conservation: Tenant hereby agrees to comply with all energy
conservation procedures, controls and requirements instituted by Landlord
pursuant to any government regulations or otherwise in good faith, including but
not limited to controls on the permitted range of temperatures, the volume of
energy consumption or the hours of operation of the Building. Institution by
Landlord of such controls and requirements shall not entitle Tenant to terminate
this Lease or to an abatement of any Rent payable hereunder.

                                       15
<PAGE>

          E. Recycling: Without limiting the foregoing, Tenant covenants and
agrees, at its sole cost and expense, to comply with all present and future
laws, orders, and regulations of the jurisdiction in which the Building is
located and of the federal, municipal, and local governments, departments,
commissions, agencies and boards having jurisdiction over the Building to the
extent that they or this Lease impose on Tenant duties and responsibilities
regarding the collection, sorting, separation, and recycling of trash. Tenant
shall pay all costs, expenses, fines, penalties, or damages that may be imposed
on Landlord or Tenant by reason of Tenant's failure to comply with the
provisions of this Section 12.D., and, at Tenant's sole cost and expense, shall
indemnify, defend and hold Landlord harmless (including legal fees and expenses)
from and against any actions, claims, and suits arising from such noncompliance,
using counsel reasonably satisfactory to Landlord.

          13.  RULES AND REGULATIONS.

          Tenant shall abide by and observe (i) the rules and regulations
attached hereto as Exhibit D-1 and such other rules and regulations as may be
made by Landlord from time to time, provided that such rules and regulations
shall not be inconsistent with the provisions of this Lease, and (ii) the
obligations imposed upon users of space in [*], as set forth in Exhibit D-2
attached hereto ("Declaration of Protective Covenants [*]"), by the Beaumeade
Association and any additions and any modifications thereto adopted from time to
time by the Beaumeade Association. Nothing contained in this Lease or in any
rules and regulations shall be interpreted to impose upon Landlord any
obligations to enforce against any tenant its rules and regulations, or the
provisions of any lease with any other tenant, and Landlord shall not be liable
to Tenant or any other entity for any violation of said rules, regulations or
lease provisions.

          14.  REPAIR OF DAMAGE CAUSED BY TENANT: INDEMNIFICATION.

               A. Repairs: Except as otherwise expressly provided in this Lease,
all injury, breakage and damage to the Land, the Building or the Premises,
caused by any act or omission of Tenant shall be repaired by and at the sole
expense of Tenant, except Landlord shall have the right, at its option, to make
such repairs and to charge Tenant for all costs and expenses incurred in
connection therewith as Additional Rent payable within ten (10) days after the
rendering of a bill therefor. Tenant shall notify Landlord promptly of any
injury, breakage or damage to the Land, the Building, or the Premises caused by
Tenant.

               B. Indemnification: Tenant hereby agrees to indemnify and hold
Landlord harmless from and against all costs, damages, claims, liabilities and
expenses, including attorney's fees, suffered by or claimed against Landlord,
directly or indirectly, based on, arising out of or resulting from: (i) Tenant's
use and occupancy of the Premises or the business conducted by Tenant therein or
Tenant's presence in the Building or on the Land (ii) the making by Tenant of
any Alterations, (iii) any act or omission of Tenant or its employees, agents or
invitees, and (iv) any breach or default by Tenant in the observance or
performance of its covenants and obligations under this Lease. In the event that
Landlord intends to settle any claim against Landlord which is the subject of
Tenant's indemnification and hold harmless obligation under this Section 14.B.
(an "Indemnified Claim"), Landlord shall use reasonable efforts to keep Tenant
informed of the progress of its negotiations with respect to the settlement

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                       16
<PAGE>

of such indemnified Claim, and, prior to entering into a settlement of such an
indemnified Claim, Landlord shall solicit Tenant's comments on the terms and
conditions of the proposed settlement, which comments shall be solely of an
advisory nature and non-binding on Landlord and shall not affect Landlord's
rights or Tenant's obligations under this Section 14.B. If Landlord or any other
indemnified party obtains recovery of any of the amounts that Tenant has paid to
such party pursuant to the indemnity set forth in this Section 14.B. or such
other Section of this Lease, then Landlord or such other indemnified party under
this Section 14.B., as applicable, shall promptly pay to Tenant the amount of
such recovery.

          15.  LIMITATION ON LANDLORD LIABILITY.

               A. Liability Standard: Landlord shall not be liable to Tenant
or any other individual or entity for any damage, loss or claim whatsoever,
except damages, losses and claims that are the direct result of either (i)
Landlord's gross negligence or willful misconduct or (ii) Landlord's breach of
this Lease; however, in no event shall Landlord be liable for consequential
damages.

               B. Limitation on Total Liability: Notwithstanding any other
provision of this Lease, it is expressly understood and agreed that the total
liability of Landlord arising out of or in connection with this Lease, the
relationship of Landlord and Tenant hereunder and/or Tenant's use of the
Premises, shall be limited to the estate of Landlord in the Building. No other
property or assets of Landlord or any partner or owner of Landlord shall be
subject to levy, execution, or other enforcement proceedings or other judicial
process for the satisfaction of any judgment or any other right or remedy of
Tenant arising out of or in connection with this Lease, the relationship of
Landlord and Tenant hereunder and/or Tenant's use of the Premises.

          16.  FIRE AND OTHER CASUALTY.

          If the Premises shall be damaged by fire or other casualty, other than
as a result of the negligence or misconduct of Tenant, the Lease shall not
terminate and, upon adjustment of insurance claims, Landlord shall repair the
damage, provided that (a) Landlord shall have no obligation to repair damage to
or replace Tenant's Personal Property, and (b) Landlord's obligation to repair
any damage under this Section 16 shall be limited to repairs necessary to
restore the Premises to its original Cold Dark Shell Condition. Except as
otherwise provided herein, if any part of the Premises are rendered untenantable
by reason of any such damage, Rent shall abate from the date of the damage to
the date the damage is repaired, as determined by Landlord, in the proportion
that the area of the untenantable part bears from time to time to the total area
of the Premises. No compensation or reduction of Rent shall be paid or allowed
for inconvenience, annoyance or injury to Tenant or Tenant's business arising
from any damage to or repair of the Premises or the Building.

          Notwithstanding the foregoing, if Landlord does not receive sufficient
insurance proceeds to fully repair the damage (it being agreed that Landlord
shall make a good faith effort to persuade any Mortgagee to make such insurance
proceeds available for the restoration of such damage, which good faith effort
shall not include any obligation on the part of Landlord to agree to any
modification of the terms of the loan secured by the Mortgage or any obligation
to pay any money to the Mortgagee or deposit any money into escrow, other than
the amount of any

                                       17
<PAGE>

deductible under Landlord's insurance policy), or if the
Building shall be so damaged that, as determined by Landlord, substantial
reconstruction of the Premises or the Building is required (whether or not the
Premises have been damaged), then Landlord, at its option, may give Tenant,
within sixty (60) days after the casualty, written notice of termination of this
Lease (the "Casualty Termination Notice"), and this Lease and the Term shall
terminate (whether or not the Term has commenced) upon the expiration of thirty
(30) days from the date of the Casualty Termination Notice, with the same effect
as if the new expiration date had been the date initially fixed for expiration
of the Term, and all Rent shall be apportioned as of such date; provided,
however, that, in the event that Landlord elects to terminate this Lease
pursuant to this Section 16, Tenant shall have the option to override the
Casualty Termination Notice and fully repair the damage to the Building by
giving written notice to Landlord, which notice shall be given, if at all,
within ten (10) days following the Casualty Termination Notice, in which event
(a) Landlord shall assign all insurance proceeds which Landlord actually
receives with respect to such fire or other casualty to Tenant, (b) Tenant shall
promptly repair such damage, and (c) such repairs by Tenant shall be subject to
Landlord's prior written approval in accordance with the provisions of Section 8
hereof.

          If the Premises or the Building shall be damaged by fire or other
casualty due to the negligence or misconduct of Tenant: (i) Landlord shall have
no obligation to repair the Premises or the Building, (ii) this Lease shall, at
Landlord's option, not terminate, (iii) Landlord may at Tenant's expense repair
the damage, provided that Landlord shall apply all insurance proceeds which
Landlord actually receives with respect to such damage toward the costs of such
repairs, and (iv) Landlord may pursue any legal and equitable remedies available
to it.

         17.   TENANT INSURANCE.

               A. Types of Insurance Required: Tenant, at its expense, shall
obtain and maintain in effect at all times during the Term an insurance policy
providing the following coverage:

                    (1) An "all risk" insurance policy covering all of Tenant's
Personal Property within, and improvements and alterations made by Tenant to,
the Premises for not less than the full replacement value thereof.

                    (2) A commercial general liability policy on an occurrence
basis, with the following limits:

<TABLE>
<S>                                                                  <C>
Each occurrence limit for bodily injury and property damage          $1,000,000
General aggregate                                                    $2,000,000
Product/completed operations aggregate                               $2,000,000
Fire damage legal liability                                          $   50,000
Medical payments (any one person)                                    $    5,000
</TABLE>

Said insurance shall name Landlord (in care of Landlord's management agent and
referring to the Building by its address), Landlord's management agent and
Mortgagee as an additional insured. The policy shall protect Landlord,
Landlord's management agent, and the Mortgagee any liability for bodily injury,
personal injury, death or property damage occurring upon, in or

                                       18
<PAGE>

about the Premises, the Building or the Land or arising out of or relating to
any risks against which Tenant is required to indemnify Landlord, Landlord's
management agent and the Mortgagee. From time to time during the Term, Landlord
may require Tenant to increase said limits of said insurance to the limits of
liability insurance then customarily required of tenants of other comparable
buildings in the city (or, if not a city, other local Jurisdiction) in which the
Building is located.

               B. Required Provisions of Policies: All insurance policies
required to be maintained by Tenant under this Lease must: (i) be issued by
insurance companies approved by Landlord; (ii) be in form and have content
satisfactory to Landlord; (iii) be written as primary policy coverage and not
contributing to or in excess of any coverage which Landlord or the Mortgagees
may carry; (iv) contain an express waiver of any right of subrogation by the
insurance company against Landlord, the Mortgagees and the Landlord's and the
Mortgagees' employees and agents; and (v) provide that the policy may not be
cancelled or permitted to lapse unless Landlord shall have received at least
fifteen (15) days prior written notice of cancellation or non-renewal. Tenant
shall deliver to Landlord (in care of Landlord's management agent and referring
to the Building by its address) certified copies or duplicate originals of each
such policy and any renewal policy, together with evidence of payment of all
applicable premiums, at least ten (10) days before the Lease Commencement Date
and at least thirty (30) days before the renewal of any policies. Any insurance
required of Tenant under this Section may be carried under a blanket policy,
provided that said policy shall specifically set forth the amount of insurance
allocated to this Lease.

               C. Effect of Tenant's Activities on Insurance: Tenant shall not
conduct or permit to be conducted any activity, or place any equipment in or
about the Land, the Building or the Premises which will increase the rate of, or
make void or voidable, any fire or other insurance maintained or required to be
maintained by Landlord or any Mortgagee on the Building, the Land or the
property kept thereon or therein, which will conflict with the provisions of any
such insurance policy or which will make it impracticable for Landlord to obtain
insurance covering any risks against which Landlord reasonably deems it
advisable to obtain insurance. In the event any increases in the rates of such
insurance are, in Landlord's reasonable judgment, due to Tenant's presence in
the Building, to any activity conducted or property installed or placed by
Tenant on or about the Land, the Building or the Premises or to Alterations
installed by Tenant or at Tenant's request, Tenant shall reimburse Landlord for
the amount of such increases promptly upon demand therefor. Statements by the
applicable insurance company or insurance rating bureau that such increases are
due to any activity, property or improvements shall be conclusive for the
purposes of determining Tenant's liability hereunder.

               D. Termination Right: Landlord shall have the right to terminate
this Lease upon thirty (30) days notice to Tenant in the event Landlord receives
notice from any of Landlord's insurance carriers that such carrier intends to
cancel its insurance on the Building, or to increase the cost of such insurance
by more than one hundred percent (100%) above the premium payable by Landlord
immediately prior to such notice, due to the activities of Tenant or the
presence of Tenant in the Building. However, Landlord shall not terminate this
Lease in the event Landlord is able, with good faith efforts, to obtain
equivalent insurance from an insurance carrier satisfactory to Landlord at a
premium not more then one hundred percent (100%) greater

                                       19
<PAGE>

than the premium for the cancelled insurance; provided that Tenant shall
reimburse Landlord for all additional premiums charged to Landlord by such new
insurance carrier. It is expressly understood that Landlord shall not have the
right to terminate this Lease pursuant to this Subsection D, if any cancellation
or rate increase is due to factors generally applicable to the insurance or
rental market, rather than to Tenant's activities or presence in the Building.

               E. Waiver: Landlord and Tenant hereby each waive and release each
other from any and all liabilities, claims and losses for which Landlord or
Tenant is or may be held liable, to the extent either party: (i) receives
insurance proceeds on account thereof, or (ii) is required to maintain insurance
pursuant to this Section, whichever is greater.

               F. Landlord's Insurance: Landlord shall maintain in force such
property insurance and liability insurance with respect to the Building as are
required by any first mortgagee or Ground Lessor or, if at any time there is no
first mortgagee and no Ground Lessor, Landlord shall maintain in force such
property insurance and liability insurance as Landlord, in its reasonable
judgment, determines to be appropriate based upon coverages in force with
respect to comparable buildings in Loudoun County, Virginia; provided, however,
that in no event shall the property insurance be less than what would be
required to prevent Landlord from being considered a co-insurer. Each property
insurance policy maintained by Landlord shall include an express waiver of any
right to subrogation by the insurance company against Tenant. All insurance
policies actually maintained by Landlord shall contain an express waiver of any
right of subrogation by the insurance Company against Tenant.

          18.  CONDEMNATION.

               A. Landlord's Right to Terminate: If a substantial part of the
Premises, the Building or the Land is taken or condemned by any governmental
authority for any purpose or is granted to any authority in lieu of condemnation
(collectively, a "taking"). Landlord shall have the right in its sole discretion
to terminate this Lease by written notice to Tenant, and upon the giving of such
notice, the Term shall terminate as of the date title vests in the authority,
and Rent shall be abated as of that date. For purposes of this Section, a
substantial part of the Premises, the Land or the Building shall be considered
to have been taken if, in the sole opinion of Landlord, the taking shall render
it commercially undesirable for Landlord to permit this Lease to continue or to
continue operating the Building.

               B. Adjustment of Rent: If a portion of the Premises is taken and
Landlord does not elect to terminate this Lease pursuant to the preceding
paragraph, then Rent shall be equitably adjusted as of the date title vests in
the authority and this Lease shall otherwise continue in full force and effect.

               C. Division of Award: Tenant shall have no claim against Landlord
arising out of or related to any taking, or for any portion of the amount that
may be awarded as a result, and Tenant hereby assigns to Landlord all its
rights, title and interest in and to any such award; provided, however, that
Tenant may assert any claim it may have against the authority for compensation
for Tenant's Personal Property for the then unamortized portion of the cost of
Additional Tenant Work and Alterations and for any relocation expenses
compensable by statute,

                                       20
<PAGE>

as long as such awards shall be made in addition to and stated separately from
the award made for the Land, the Building and the Premises.

          19.  DEFAULT.

               A.   Default of Tenant:  The following events shall be a default
by Tenant (a "Default") under this Lease:

                    (1) Failure of Tenant to pay Rent as and when due, if the
failure continues for five (5) days after notice from Landlord specifying the
failure.

                    (2) Failure of Tenant to comply with or perform any covenant
or obligation of Tenant under this Lease, other than those concerning the
payment of Rent, if the failure continues for twenty (20) days after notice from
Landlord to Tenant specifying the failure; provided, however, that if the
failure on the part of Tenant is not capable of being cured within such 20-day
period but Tenant expeditiously commences to cure same and diligently proceeds
with such cure, Tenant's time to cure such failure shall be extended for the
time necessary to cure same, but in no event longer than sixty (60) days,
inclusive of the original 20-day period.

                    (3)  [Intentionally omitted.]

                    (4) If Tenant, any guarantor of Tenant's performance
hereunder (a "Guarantor") or, if Tenant is a partnership, any partner of Tenant
("Partner"), shall file a voluntary petition in bankruptcy or insolvency, shall
be adjudicated bankrupt or insolvent or shall file a petition or answer seeking
any reorganization, arrangement, composition, readjustment, liquidation,
dissolution or similar relief under any present or future federal, state or
other law, or shall make an assignment for the benefit of creditors, or shall
seek or acquiesce in the appointment of any trustee, receiver or liquidator of
Tenant or of any Guarantor or Partner or of all or any part of the property of
Tenant or of such Guarantor or Partner.

                    (5) If, within thirty (30) days after the commencement of
any proceeding against Tenant or a Guarantor or Partner, whether by the filing
of a petition or otherwise, seeking any reorganization, arrangement,
composition, readjustment, liquidation, dissolution or similar relief under any
present or future applicable federal, state or other law, such proceeding shall
not have been dismissed or if, within thirty (30) days after the appointment of
any trustee, receiver or liquidator of Tenant or any Guarantor or Partner, or of
all or any part of the property of Tenant or of any Guarantor or Partner without
the acquiescence of such individual or entity, such appointment shall not have
been vacated or otherwise discharged, or if any execution or attachment shall
have been issued against the property of Tenant or of any Guarantor or Partner,
pursuant to which the Premises shall be taken or occupied or attempted to be
taken or occupied.

                    (6) If Tenant fails to take possession of the Premises on
the Lease Commencement Date or vacates, abandons or ceases to carry on its
ordinary activities in the Premises prior to the Lease Expiration Date, with or
without an intention of paying Rent; provided, however, that if (i) Tenant gives
Landlord at least thirty (30) days prior written notice that it intends to
vacate the Premises, (ii) Tenant pays the full amount of all Rent when due under

                                       21
<PAGE>

this Lease while the Premises are vacant, (iii) the fact that the Premises are
vacant does not adversely affect the Building or other tenants of the Park and
does not result in any liability to, or expenditure of funds by, Landlord, and
(iv) Tenant leaves the Premises in a condition satisfactory to Landlord and
continues to maintain the Premises in a condition satisfactory to Landlord
throughout the remainder of the Term, then, and in such event only, Tenant shall
not be deemed to be in Default under this Section 19.A.(6) and Landlord shall
have the right, exercisable by sending written notice to Tenant, to sublet from
Tenant for the balance of the Term of this Lease all or any portion of the
Premises at Tenant's then rental rate hereunder, or to terminate this Lease as
to all or any portion of the Premises, which rights of Landlord as to subletting
and termination shall be exercisable by Landlord in its sole discretion.

               B.   Remedies Upon Default: Upon the occurrence of a Default,
Landlord shall have the right, then or at any time

                    (1) Without demand or notice, to reenter and take possession
of all or any part of the Premises, to expel Tenant and those claiming through
Tenant and to remove any property therein, either by summary proceedings or by
any other action at law, in equity or otherwise, with or without terminating
this Lease without being deemed guilty of trespass and without prejudice to any
other remedies of Landlord for breach of this Lease, and/or

                    (2) To give Tenant written notice of Landlord's intent to
terminate this Lease, and on the date specified in Landlord's notice, Tenant's
right to possession of the Premises shall cease and this Lease shall terminate.

          If Landlord elects to terminate this Lease, everything contained in
this Lease on the part of Landlord to be done shall cease, without prejudice to
Landlord's right to recover from Tenant all Rent, as set forth in Subsections C.
and D. below. If Landlord elects to reenter pursuant to Subsection B.(1) above,
Landlord may terminate this Lease, or, from time to time without terminating
this Lease, may relet all or any part of the Premises as the agent of Tenant,
for such term, at such rental and upon such other provisions as Landlord deems
acceptable, with the right to make any alterations and repairs to the Premises
that Landlord deems appropriate, at Tenant's expense. No such reentry or taking
of possession of the Premises shall be construed as an election to terminate
this Lease, unless notice of such intention is given pursuant to Subsection
B.(2) above, or unless termination be decreed by a court of competent
jurisdiction at the instance of Landlord. Landlord shall in no event be under
any obligation to relet any part of the Premises.

               C.   Liability of Tenant: If Landlord terminates this Lease or
reenters the Premises (with or without terminating this Lease), Tenant shall
remain liable (in addition to all other liabilities of Tenant accrued at the
time of the Default) for the sum of (i) any unpaid Rant accrued prior to the
time of termination and/or reentry, as the case may be, plus interest thereon
from the due date at the Default Rate, (ii) all Base Rent and Additional Rent
provided for in this Lease from the time of termination and/or reentry, as the
case may be, until the date this Lease would have expired had a Default not
occurred, plus interest thereon from the due date at the Default Rate, (iii) any
and all expenses (including but not limited to attorneys' and brokerage fees)
incurred by Landlord in reentering and repossessing the Premises, in correcting
any default, in painting, altering or repairing the Premises in order to place
the Premises in first-class rentable

                                       22
<PAGE>

condition (whether or not the Premises are relet), in protecting and preserving
the Premises and in reletting or attempting to relet the Premises, and (iv) any
other amounts necessary to compensate Landlord for any other injury or detriment
caused by the Default, minus the net proceeds (after deducting any rental
abatements, tenant improvement allowances and other concessions and inducements)
actually received by Landlord, if any, from any reletting to the extent
attributable to the period prior to the date this Lease would have expired had a
Default not occurred. Landlord shall have the option to recover any damages
sustained by Landlord either at the time of reletting, or in separate actions
from time to time as said damages shall have been made more easily ascertainable
by successive relettings or, at Landlords' option, to defer any such recovery
until the date this Lease would have expired in the absence of a Default, in
which event Tenant hereby agrees that the cause of action shall be deemed to
have accrued on the aforesaid date. The provisions of this Section shall be in
addition to, and shall not prevent the enforcement of, any claim Landlord may
have for anticipatory breach of this Lease.

               D. Liquidated Damages: In addition to Landlord's rights pursuant
to Subsection C. above, if Landlord terminates this Lease, Landlord shall have
the right at any time, at its sole option, to require Tenant to pay to Landlord
on demand, as liquidated damages, the sum of (i) the total of the Base Rent,
Additional Rent and all other sums which would have been payable under this
Lease from the date of Landlord's demand for liquidated damages ("Landlord's
Demand") until the date this Lease would have terminated in the absence of the
Default, discounted to present value at the rate of five percent (5%) per annum
(the "Discount Rate"), (ii) all unpaid Rent accrued prior to the time of
Landlord's Demand, plus interest thereon from the due date at the Default Rate,
(iii) any and all expenses (including but not limited to attorneys' and
brokerage fees) incurred by Landlord in reentering and repossessing the
Premises, in correcting any default, in painting, altering or repairing the
Premises in order to place the Premises in first-class rentable condition
(whether or not the Premises are relet), in protecting and preserving the
Premises and in reletting or attempting to relet the Premises, and (iv) any
other amounts necessary to compensate Landlord for any other injury or detriment
caused by the Default; minus the sum of (a) the net fair market rental value of
the Premises for the period referred to in Subsection D.(i) above, discounted to
present value at the Discount Rate, and (b) any sums actually paid by Tenant to
Landlord pursuant to Subsection C. above; provided, however, that if said
damages shall be limited by law to a lesser amount, Landlord shall be entitled
to recover the maximum amount permitted by law. The "net fair market rental
value" referred to in Subsection D.(a) above shall be the fair market rental
value of the Premises at the time of Landlord's Demand, reduced by any rental
abatements, tenant improvement allowances and other concessions and inducements
generally provided by landlords seeking to tease comparable commercial property
in the area of the Premises at the time of Landlord's Demand. If reletting is
accomplished within a reasonable time after Lease termination, the 'net fair
market rental value' referred to in Subsection D (a) above shall be deemed prima
facie to be the net rental income (after deducting any rental abatements, tenant
improvement allowances and other concessions and inducements) realized upon such
reletting.

               E. Waiver: Tenant, on its own behalf and on behalf of all persons
and entities claiming through Tenant, including but not limited to creditors of
Tenant, hereby waives any and all rights and privileges which Tenant and such
other persons and entities might otherwise have under any present or future law:
(i) to redeem the Premises, (ii) to reenter or repossess the Premises, or (iii)
to restore the operation of this Lease, with respect to any

                                       23
<PAGE>

dispossession of Tenant by judgment or warrant of any court, any reentry by
Landlord or any expiration or termination of this Lease, whether by operation of
law or pursuant to the provisions of this Lease. Tenant hereby expressly waives
receipt of a Notice to Quit.

               F.   Lien on Personal Property:  [Intentionally omitted.]

               G.   Right of Distress:  Landlord shall, to the extent permitted
by law, have a right of distress for Rent.

               H. Right of Landlord to Cure: If Tenant defaults in the making of
any payment or in the doing of any act required to be made or done by Tenant
under this Lease, then Landlord may, at its option, make such payment or do such
act, and the expenses thereof, with interest thereon at the Default Rate, from
the date paid by Landlord, shall constitute Additional Rent hereunder due and
payable by Tenant with the next payment of Monthly Base Rent.

               I. Attorneys' Fees: In the event of any Default hereunder, Tenant
shall pay to Landlord all reasonable attorneys fees incurred by Landlord in
connection with such Default or the enforcement of Landlord s rights or remedies
arising in connection therewith, whether or not this Lease is terminated and
whether or not Landlord institutes any lawsuit against Tenant as a result of
such Default. In the event that either party initiates litigation against the
other party, the prevailing party in such litigation, based upon a judgment by a
court of competent jurisdiction, shall be entitled to recover from the
non-prevailing party the prevailing party's court costs and reasonable
attorneys' fees in connection with such litigation; provided, however, that in
the event that any such litigation is resolved without a final determination by
a court in a manner which results in the non-initiating party paying
substantially all of the money which was sought by the initiating party in such
litigation or taking' substantially the same action as was sought by the
initiating party in such litigation, then, in either of such cases, the
non-initiating party shall pay to the initiating party the initiating party's
court costs and reasonable attorneys' fees in connection with such litigation.

               J. Survival: Tenant's liability pursuant to this Section 19 shall
survive the termination of this Lease, the institution of summary proceedings
and/or the issuance of a warrant thereunder.

          20.  NO WAIVER.

          No failure or delay by Landlord in enforcing its right to strict
performance by Tenant of every provision of this Lease or in exercising any
right or remedy hereunder, and no acceptance by Landlord of full or partial rent
during the continuance of any Default, shall constitute a waiver of the
provision or the Default, and no provision shall be waived or modified except by
a written instrument executed by Landlord. No payment by Tenant, or receipt by
Landlord, of a lesser amount than the full Rent shall be deemed to be other than
a payment on account, notwithstanding any endorsement or statement on any check
or letter accompanying any payment of any Rent. No waiver of any Default or
settlement of any proceeding instituted on account of any claimed Default shall
affect or alter this Lease or constitute a waiver of any of Landlord's rights
hereunder.

                                       24
<PAGE>

          21.  HOLDING OVER.

          If Tenant shall be in possession of the Premises after termination of
this Lease (whether by normal expiration of the Term or otherwise), at Landlord
s option: (i) Landlord may deem Tenant to be occupying the Premises as a tenant
from month-to month, (a) for the first month of such holdover, at the sum of one
hundred fifty percent (150%) of the Monthly Base Rent in effect for the last
full month of the Term, (b) for the second month of such holdover, at the sum of
one hundred seventy-five percent (175%) of the Monthly Base Rent in effect for
the last full month of the Term, and (c) thereafter, at the sum of two hundred
percent (200%) of the Monthly Base Rent in effect for the test full month of the
Term, and, in each case (that is, with respect to any holdover to which any of
the immediately foregoing clauses (a), (b), or (c), or any combination thereof,
applies), plus the monthly installment of Additional Rent which is then payable
pursuant to Section 5.C. of this Lease, and subject to all of the other
provisions of this Lease, as applicable to a month-to-month tenancy, or (ii)
Landlord may exercise any or all remedies for Default and at law and in equity,
including but not limited to an action against Tenant for wrongfully holding
over.

          22.  SUBORDINATION.

               A. Lease Subordinate: This Lease shall be subject and subordinate
to the lien of any and all Mortgages and to any Ground Leases, and any and all
renewals, extensions, modifications, recastings and refinancings thereof. This
clause shall be self-operative, without execution of any further instrument; but
if requested by Landlord or any Mortgagee, Tenant shall promptly execute a
certificate or other document evidencing and providing for such subordination.
Landlord shall have the right to execute said document on behalf of Tenant if
Tenant fails to do so within five (5) days after receipt of the request. Tenant
agrees that, if any Mortgage is foreclosed or Ground Lease terminated, upon
request by the purchaser at the foreclosure sale or Ground Lessor, as the case
may be, Tenant shall attorn to and recognize the purchaser or Ground Lessor as
the landlord under this Lease and shall make all payments required hereunder to
such new landlord without any deduction or set-off of any kind whatsoever.
Tenant waives the provisions of any law or regulation, now or hereafter in
effect, which may give or purport to give Tenant any right to terminate or
otherwise affect this Lease or the obligations of Tenant hereunder in the event
that any such foreclosure, termination or other proceeding is filed, prosecuted
or completed. Notwithstanding anything herein to the contrary, any Mortgagee may
at any time subordinate the lien of its Mortgage to the operation and effect of
this Lease without Tenant's consent, by giving Tenant written notice of such
subordination, in which event this Lease shall be deemed to be senior to such
Mortgage, and thereafter such Mortgagee shall have the same rights as it would
have had if this Lease had been executed, delivered and recorded before said
Mortgage. Landlord shall obtain from any current Mortgagee or Ground Lessor a
non-disturbance agreement for the benefit of Tenant in such Mortagee's or Ground
Lessor's, as the case may be, usual form; provided, however, that Tenant shall
pay all costs incurred by Landlord which are imposed by such Mortgagee or Ground
Lessor, as the case may be, with respect to such non-disturbance agreement.
Furthermore, Landlord shall obtain from any future Mortgagee or Ground Lessor a
non-disturbance agreement for the benefit of Tenant in such Mortgagee's or
Ground Lessor's, as the case may be, usual form; provided, however, that (i)
Tenant shall pay all costs incurred by Landlord which are imposed by such
Mortagee or Ground Lessor, as the case may be, with respect to such
non-disturbance agreement,

                                       25
<PAGE>

and (ii) in the event that either (A) Tenant's net worth is not equal to at
least fifty percent (50%) of Tenant's net worth as shown on Exhibit H attached
hereto and made a part hereof, or (B) Tenant's creditworthiness is not then
greater than or equal to, in Landlord's sole and absolute discretion, Tenant's
creditworthiness as shown on said Exhibit H, Landlord shall not have any
obligation to obtain such non-disturbance agreement; provided, however, that
even in such circumstance(s), Landlord shall nevertheless use commercially
reasonable efforts to obtain such non-disturbance agreement.

               B. Modifications to Lease: In the event any of Landlord's
insurance carriers or any Mortgagee requests modifications to this Lease, Tenant
shall execute a written amendment incorporating such requested modifications
within thirty (30) days after the same has been submitted to Tenant by Landlord,
provided that such modifications do not adversely affect Tenant's use of the
Premises as herein permitted or increase the rentals and other sums payable by
Tenant hereunder. In the event Tenant refuses or fails to execute such amendment
within thirty (30) days, Landlord shall have the right, at its sole option, in
addition to Landlord's other remedies for Default, to terminate and cancel this
Lease by written notice to Tenant specifying the date on which this Lease will
terminate. From and after said termination date, both Landlord and Tenant shall
be relieved of any and all further obligations hereunder, except liabilities
arising prior to the date of termination.

          23.  ASSIGNMENT AND SUBLETTING.

               A. No Transfer Without Consent. Tenant shall not, without the
prior written consent of Landlord in each instance (which consent may be
withheld in Landlord's sole and absolute discretion) (i) assign, mortgage or
otherwise encumber this Lease or any of its rights hereunder, (ii) sublet the
Premises or any part thereof or permit the occupancy or use of the Premises or
any part thereof by any persons or entities other than Tenant; or (iii) permit
the assignment of this Lease or any of Tenant's rights hereunder by operation of
law (each of the actions set forth in clauses (i), (ii) and (iii) of this
sentence is referred to herein as a "Transfer"). Any attempted assignment,
mortgaging or encumbering of this Lease or any of Tenants rights hereunder and
any attempted subletting or grant of a right to use or occupy all or a portion
of the Premises in violation of the foregoing sentence shall be void.
Notwithstanding any provision of this Lease to the contrary, Tenant shall have
the right, without obtaining the prior written consent of Landlord, to Transfer
to (a) any parent corporation of Tenant, (b) any subsidiary corporation of
Tenant or of Tenant's parent corporation, (c) any entity in which Tenant, any
parent corporation of Tenant or any subsidiary corporation of Tenant or of
Tenant's parent corporation holds a majority the outstanding shares or ownership
interests, or (d) any corporation resulting from the merger, consolidation or
reorganization of Tenant or Tenant's parent corporation with another corporation
(any entity which is described in clauses (a), (b), (c) or (d) is hereinafter
referred to as an "Affiliate"); provided, however, that the combined net worth
and creditworthiness of such Affiliate and Tenant shall be at least equal to the
greater of either Tenant's net worth and creditworthiness as of the Effective
Date of this Lease or Tenant's net worth and creditworthiness as of the date of
such Transfer. In addition, Landlord's consent shall not be required for any
agreements with Customers (as such term is defined in the Special Tenant
Requirements which are attached hereto as Exhibit G and made a part hereof) (the
"Customer Agreements"). Any and all of the transactions permitted under this
Section 23.A. shall not constitute an assignment, subletting or other
transaction requiring the consent of Landlord under

                                       26
<PAGE>

the provisions of this Section 23 and shall not be subject to the consent
requirements hereof or any of the provisions of Section 23.B., 23.C. or 23.D.

               B.   Take-Back Rights: In addition, Tenant may not assign this
Lease, nor sublet (or permit occupancy or use of) the Premises, or any part
thereof, without giving Landlord thirty (30) days prior written notice thereof.
For thirty (30) days following receipt of said notice, in the event that either
(a) such proposed sublease would result in an aggregate of at least 140,000
rentable square feet of the area comprising the Premises being sublet, or (b)
Tenant is proposing assisting the Lease to any party other than an Affiliate, In
accordance with the terms and conditions of Section 23.A. hereof, Landlord shall
have the right, exercisable by sending notice to Tenant, to sublet from Tenant
for the balance of the Term of this Lease (i) all of the Premises in the event
Tenant notified Landlord of its desire to assign this Lease, or (ii) so much of
the Premises as Tenant intends to sublet in the event Tenant notified Landlord
of its desire to sublet the Premises or permit another to make use thereof, at
the same rental Tenant is obligated to pay to Landlord hereunder. In the event
Landlord does not exercise the aforesaid right within said thirty (30) days,
Tenant may attempt to assign, sublet or permit use of this Lease or such space;
provided that Tenant shall obtain the prior written consent of Landlord as set
forth in Subsection A. above. In the event that Tenant defaults hereunder,
Tenant hereby assigns to Landlord the Rent due from any assignee or subtenant
and hereby authorizes each such party to pay said Rent to Landlord.

               C.   Transfer of Stock: If Tenant and/or any Guarantor is a
corporation, then the sale, issuance or transfer of any voting capital stock of
Tenant or any Guarantor, by the person, persons or entities owning a controlling
interest therein as of the date of this Lease, which results in a change in the
voting control of Tenant or the Guarantor, shall be deemed an assignment within
the meaning of this Section 23; provided, however, that the provisions of this
Section 23.C. shall not be applicable to (i) transfers of stock among persons
who are shareholders of Tenant as of the Effective Date of this Lease, (ii)
transfers of stock to any spouse, child, grandchild, sibling or aunt or uncle of
any shareholder, or to the spouse of any of the foregoing persons, or any trust
for the benefit of any of the foregoing persons, or (iii) transfers of stock at
any time that Tenant is an entity the shares of which are publicly held and
traded on a national or regional stock exchange. If Tenant and/or any Guarantor
is a partnership, the sale or transfer of the partnership share, or any portion
thereof, of any general partner shall be deemed an assignment of this Lease.

               D.   Expenses and Profits; Effect of Consent:

                    (1) In the event Landlord permits Tenant to assign or
sublet all or a portion of the Premises to a third party, fifty percent (50%)
of any sums that are paid by such third party for the right to occupy the
Premises, in excess of the sum of (i) the Rent then in effect plus (ii)
reasonable costs actually incurred by Tenant in connection with such sublease
or assignment for brokerage commissions, advertising fees, attorneys' fees and
tenant improvements, and the then unamortized costs of any initial Additional
Tenant Work and of Tenant's initial buildout of the Premises shall be paid by
Tenant to Landlord on a monthly basis as Additional Rent. This Section
23.D.(1) shall not apply to Customer Agreements.

                                       27
<PAGE>

                    (2) Tenant shall be responsible for all costs and
expenses, including attorneys' fees, incurred by Landlord in connection with
any proposed or purported assignment or sublease and an administrative fee of
Two Thousand Five Hundred Dollars ($2,500.00).

                    (3) The consent by Landlord to any assignment or
subletting shall neither be construed as a waiver or release of Tenant from
any covenant or obligation of Tenant under this Lease, nor as relieving Tenant
from giving Landlord the aforesaid thirty (30) days notice of, or from
obtaining the consent of Landlord to, any further assignment or subletting.
The collection or acceptance of Rent from any such assignee or subtenant shall
not constitute a waiver or release of Tenant from any covenant or obligation
of Tenant under this Lease, except as expressly agreed by Landlord in writing.

               E.   Tenant's Equipment Financing: The foregoing notwithstanding,
Tenant may grant a security interest in rights under this Lease to the entity
that provides equipment financing to Tenant. The entity holding the security
interest in this Lease as authorized under this Section 23.E. may foreclose on
such security interest and transfer this Lease to the party purchasing at the
foreclosure, provided that Landlord consents to such party as the new Tenant
hereunder, which consent shall not be unreasonably withheld or delayed, provided
that all of the following conditions are satisfied: (1) there shall be no
default at the time of the transfer, (2) the proposed new tenant shall be
creditworthy, (3) the proposed new tenant shall not be a governmental entity or
a person or entity enjoying sovereign or diplomatic immunity, (4) the use of the
Premises by the proposed new tenant shall not attract a volume, frequency or
type of visitor or employee to the Building which is not consistent with the
standards of a high quality office building, (5) the proposed new tenant shall
specifically covenant and agree to perform the obligations of Tenant hereunder
and to occupy the Premises subject to the provisions of this Lease, and (6)
Tenant remains liable for the faithful performance of this Lease.

          24.  TRANSFER BY LANDLORD.

          Landlord (and any successor or affiliate of Landlord) may freely sell,
assign or transfer all or any portion of its interest in this Lease or the
Premises, the Building or the Land and, in the event of any such sale,
assignment or transfer, shall be relieved of any and all obligations under this
Lease from and after the date of the sale, assignment or transfer. From and
after said date, Tenant shall be bound to such purchaser, assignee or other
transferee, as the case may be, as though the latter had been the original
Landlord hereunder, provided that the purchaser, assignee or transferee agrees
to assume the obligations of Landlord hereunder.

          25.  INABILITY TO PERFORM.

          This Lease and Tenant's obligation hereunder shall in no way be
affected, impaired or excused, nor shall Tenant have any claim against Landlord
for damages, because Landlord, due to Unavoidable Delays, is unable to fulfill
any of its obligations under this Lease, including, but not limited to, any
obligations to provide any services, repairs, replacements, alterations or
decorations or to supply any improvements, equipment or fixtures.

                                       28
<PAGE>

          26.  ESTOPPEL CERTIFICATES.

          Tenant shall, without charge, within ten (10) days after receipt of
any request therefor, execute and deliver to Landlord a certificate stating: (i)
whether this Lease is unmodified and in full force and effect (or if there have
been modifications, that the Lease is in full force and effect and seeing forth
all such modifications); (ii) whether there then exist any defenses against the
enforcement of any right of Landlord hereunder (and, if so, specifying the same
in detail); (iii) the dates to which rent and any other charges hereunder have
been paid by Tenant; (iv) that Tenant has no knowledge of any then uncured
defaults under this Lease (or, if Tenant has knowledge of any such defaults,
specifying the same in detail); (v) that Tenant has no knowledge of any event
that will or may result in the termination of this Lease (or if Tenant has such
knowledge, specifying the same in detail); (vi) the address to which notices to
Tenant are to be sent; and (vii) such other information as may be reasonably
requested. It is understood that any such certificate may be relied upon by
Landlord, any Mortgagee, prospective Mortgagee, Ground Lessor, prospective
Ground Lessor, or purchaser or prospective purchaser of the Land or the
Building. On not more than one (1) occasion in each Fiscal Year, within ten (10)
days after receipt of a request therefor from Tenant, Landlord shall execute and
deliver to Tenant a certificate which addresses the matters described in clauses
(i) through (vi) of the preceding sentence.

          27.  COVENANT OF QUIET ENJOYMENT.

          Landlord covenants that it has the right to make this Lease and that,
if Tenant shall pay all Rent and perform all of Tenant's other obligations under
this Lease, Tenant shall have the right, during the Term and subject to the
provisions of this Lease, to quietly occupy and enjoy the Premises without
hindrance by Landlord or its successors and assigns.

          28.  WAIVER OF JURY TRIAL.

          Landlord and Tenant hereby waive trial by jury in any action,
proceeding or counterclaim brought by either of them against the other with
respect to any matter arising out of or connected with this Lease.

          29.  BROKERS.

          Landlord and Tenant each represents and warrants to the other that,
except as hereinafter set forth, neither of them has employed any broker in
procuring or carrying on any negotiations relating to this Lease. Landlord and
Tenant shall indemnify and hold each other harmless from any loss, claim or
damage relating to the breach of the foregoing representation and warranty.
Landlord recognizes only Advantis, Inc., as agent of Landlord, as broker with
respect to this Lease and agrees to be responsible for the payment of any
leasing commissions owed to said brokers.

          30.  CERTAIN RIGHTS RESERVED BY LANDLORD.

          Landlord shall have the following rights, exercisable without notice,
without liability for damage or injury to property, person or business and
without effecting an eviction,

                                       29
<PAGE>

constructive or actual, or disturbance of Tenant's use or possession of the
Premises or giving rise to any claim for set-off, abatement of Rent or
otherwise:

               A.   To change the Park's and the Building's name or street
address.

               B.   [Intentionally omitted.]

               C. To designate and approve, prior to installation, all window
shades, blinds, drapes, awnings, window ventilators, lighting and other similar
equipment to be installed by Tenant that may be visible from the exterior of the
Premises or the Building.

               D. To make repairs, whether structural or otherwise, in, to and
about the Building and any part thereof, and for such purposes to enter the
Premises, and, during the continuance of any such work, to close temporarily
doors, entry ways, common areas in the Building and to interrupt or temporarily
suspend Building services and facilities, all without affecting Tenant's
obligations hereunder, as long as the Premises remain tenantable.

               E. To grant to anyone the exclusive right to conduct any business
or render any service in the Parks provided Tenant is not thereby excluded from
uses expressly permitted herein.

               F. To alter, relocate, reconfigure and reduce the common areas of
the Park, as long as the Premises remain reasonably accessible.

               G. To alter, relocate, reconfigure, reduce and withdraw the Park
Common Areas located outside the Building, including parking and access roads,
as long as the Premises remain reasonably accessible; provided, however, that
any such alteration, relocation, reconfiguration, reduction or withdrawal of the
Park Common Areas located outside the Building not adversely affect Tenant's
parking rights as set forth in this Lease.

               H. To erect, use and maintain pipes and conduits in and through
the Premises, if required by any applicable law or governmental regulation.

          31.  NOTICES.

          No notice, request, approval, waiver or other communication which may
be or is required or permitted to be given under this Lease shall be effective
unless the same is in writing and hand-delivered, sent by registered or
certified mail, return receipt requested, first-class postage prepaid, or sent
with charges prepaid by a nationally recognized air courier service, addressed
as follows:

          If to Landlord:

               TrizecHahn Mid-Atlantic Management Services LLC
               1250 Connecticut Avenue, N.W.
               Suite 500
               Washington, D.C. 20036
               Attention: Portfolio Manager - [*]

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                       30
<PAGE>

          If to Tenant:

Prior to the Lease Commencement Date:

Equinix, Inc.                                     ____________________________
901 Marshall Street                               ____________________________
Redwood City, California 94063                    ____________________________
Attn: Mr. Keith Taylor                            ____________________________

or at any other address of which either party shall notify the other in
accordance with this Section.  Such communications, if sent by registered or
certified mail, shall be deemed to have been given to three (3) business days
after the date of mailing, or if sent by a nationally recognized air courier
service, shall be deemed to have been given one (1) business day after the date
of deposit of the notice with such service.  If any Mortgagee shall notify
Tenant that it is the holder of a Mortgage affecting the Premises, no notice,
request or demand thereafter sent by Tenant to Landlord shall be effective until
a copy of same shall be sent to such Mortgagee in the manner prescribed in this
Section at such address as such Mortgagee shall designate.

          32.  MISCELLANEOUS PROVISIONS.

               A.   Benefit and Burden:  The provisions of this Lease shall be
binding upon, and shall inure to the benefit of, the parties hereto and each of
their respective successors and permitted assigns.

               B.   Governing Law:  This Lease shall be construed and enforced
in accordance with the laws of the jurisdiction in which the Building is
located.

               C.   No Partnership:  Nothing contained in this Lease shall be
deemed to create a partnership or joint venture between Landlord and Tenant, or
to create any other relationship between the parties other than that of Landlord
and Tenant.

               D.   Delegation by Landlord:  Wherever Landlord has the authority
to take any action under this Lease, Landlord shall have the right to delegate
such authority to others, and Landlord shall be responsible for the authorized
actions of such agents, employees and others, to the same extent as if Landlord
had taken such action itself.

               E.   Tenant Responsibility for Agents:  In any case where Tenant
is responsible for performing or refraining from an act or for preventing an
action or result from occurring, Tenant shall also be responsible for any
actions taken or omitted by Tenant's agents, employees, business invitees,
licensees, contractors, subtenants, family members, guests and any other
individuals or entities present in the Building or on the Land at Tenant's
invitation.

               F.   Invalidity of Particular Provisions:  If any provision of
this Lease or the application thereof to any person, entity or circumstance
shall, to any extent, be held invalid or unenforceable, the remaining provisions
and the application of such invalid or unenforceable provisions to persons,
entities and circumstances other than those as to which it is held invalid or
unenforceable, shall not be affected thereby.  Each provision of this Lease
shall be valid and enforced to the fullest extent permitted by law.

                                       31
<PAGE>

               G.   Counterparts: This Lease may be executed in several
counterparts, all of which shall constitute one and the same document.

               H.   Entire Agreement:  This Lease, and any exhibits and addenda
attached hereto, embody the entire agreement of the parties hereto relating to
the Premises, and no representations, inducements or agreements, oral or
otherwise, between the parties not contained in this Lease or in the exhibits or
addenda shall be of any force or effect.  No rights, privileges, easements or
licenses are granted to Tenant hereby, except as expressly set forth herein.

               I.   Amendments:  This Lease may not be modified in whole or in
part in any manner other than by an agreement in writing.

               J.   Mortgagee's Performance:  Tenant shall accept performance of
any of Landlord's obligations hereunder by any Mortgagee.

               K.   Limitation on Interest:  In any case where this Lease
provides for a rate of interest that is higher than the maximum rate permitted
by law, the rate specified herein shall be deemed to equal, and the party
designated as recipient of such interest shall be entitled to receive, the
maximum rate of interest permitted by law.

               L.   Remedies Cumulative:  All rights and remedies of Landlord
shall be cumulative and shall not be exclusive of any other rights or remedies
of Landlord hereunder or now or hereafter existing at law or in equity.

               M.   Annual Financial Statements:  Within five (5) business days
following Landlord's request therefor, Tenant shall submit to Landlord an
audited financial statement covering the preceding Fiscal Year, which has been
prepared in accordance with generally accepted accounting principles by an
independent certified public accountant.  Tenant's most recent audited financial
statement as of the Effective Date of this Lease is attached hereto and made a
part hereof as Exhibit H.

          33.  LENDER APPROVAL [Intentionally omitted.].

          34.  PARKING.

          Parking will be made available to Tenant pursuant to the provisions of
Exhibit E attached hereto.

          35.  SECURITY DEPOSIT.

               A. Amount and Uses: Landlord acknowledges receipt from Tenant of
[*] Dollars ($ [*]) (the "Security Deposit"), to be held by Landlord as security
for the payment of all Rent payable by Tenant and for the faithful performance
by Tenant of all other obligations of Tenant under this Lease. Notwithstanding
the foregoing, the Security Deposit shall be reduced (i) by [*] Dollars ($ [*])
after the expiration of the third (3rd) Lease Year of the Term, (ii) by Dollars
($ [*]) after the expiration of the sixth (6th) Lease Year of the Term, and
(iii) by

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                       32
<PAGE>

[*] Dollars ($[*]) after the expiration of the seventh (7th) Lease Year of the
Term, except that there shall be no such reduction for any Lease Year at the end
of which either (a) there exists any Default or any circumstance which with the
giving of notice or the passage of time would constitute a Default under this
Lease or (b) Tenant's net worth and creditworthiness are not at least equal, in
Landlord's reasonable judgment, to Tenant's net worth and creditworthiness as of
the Effective Date of this Lease, until such time as such Default or
circumstance has been cured, at which time the reduction in the Security Deposit
shall resume. After the end of the seventh (7th) Lease Year, the required amount
of the Security Deposit at that time shall remain as the Security Deposit for
the remainder of the Term hereof. Said Security Deposit shall be repaid to
Tenant after the termination of this Lease (or any renewal thereof) provided
Tenant shall have made all such payments and performed all such obligations
hereunder. Landlord shall not be required to maintain the Security Deposit in a
separate account. The Security Deposit shall not be mortgaged assigned
transferred or encumbered by Tenant without the prior written consent of
Landlord and any such act shall be void. Landlord may at Landlord's option
appropriate and apply the entire Security Deposit or so much thereof as Landlord
believes may be necessary to compensate Landlord for the payment of any past-due
Rent and for loss or damage sustained by Landlord due to any Default. In the
event Landlord appropriates or applies the Security Deposit in such a manner
Tenant within five (5) days after notice thereof shall pay to Landlord an amount
sufficient to restore the Security Deposit to the original sum deposited Tenants
failure to restore any such deficiency shall constitute a Default hereunder. In
the event of bankruptcy or other debtor creditor proceedings by or against
Tenant the Security Deposit shall be applied first to the payment of Rent due
Landlord for all periods prior to the filing of such proceedings. In lieu of the
cash Security Deposit herein above provided for, Tenant shall have the option to
deposit with Landlord a letter of credit (the "Letter of Credit") in an amount
equal to the Security Deposit, which Letter of Credit shall thereupon constitute
the Security Deposit. The Letter of Credit shall be maintained throughout the
remainder of the Term. Any Letter of Credit delivered to Landlord by Tenant
shall be an unconditional, irrevocable letter of credit in a form and from a
financial institution located in the Washington, D.C. metropolitan area, capable
of being drawn upon at any of the such issuer's offices in the Washington, D.C.
metropolitan area, and acceptable to Landlord in its sole discretion; provided,
however, that the initial issuer of the Letter of Credit may be Comercia Bank of
California ("Comercia") if the Letter of Credit is capable of being drawn upon
in any of Comercia's offices in California. Said Letter of Credit shall provide
that it shall expire on the thirtieth (30th) day following the date of
expiration of the Term of this Lease. At Tenant's option, said Letter of Credit
shall have a term equal to the period expiring on the first anniversary of the
date of issuance thereof, in which event Tenant covenants that a renewal of said
Letter of Credit shall be delivered to Landlord by that date which is thirty
(30) days prior to the expiration date thereof, and thereafter a renewal of the
Letter of Credit shall be delivered to Landlord by Tenant by that date which is
thirty (30) days prior to each succeeding anniversary of the original expiration
date of the Letter of Credit. If Tenant falls to so renew and deliver said
Letter of Credit to Landlord by the thirtieth (30th) day preceding each said
expiration date, such failure shall constitute a Default hereunder (as to which
no cure period shall be applicable) and Landlord may draw upon the Letter of
Credit then in effect without the necessity of any other monetary or other
default hereunder by Tenant, in which event the proceeds thereof shall be held
by Landlord. Said Letter of Credit shall provide that Landlord shall be
permitted to draw on same on multiple occasions following the occurrence of a
Default by Tenant under this Lease;

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.
                                       33
<PAGE>

provided, however, that in the event that said Letter of Credit would expire
during the pendency of any litigation to resolve whether such Default has
occurred, Landlord may draw upon said Letter of Credit prior to the expiration
thereof. In the event that Landlord draws upon the Letter of Credit after a
Default by Tenant as aforesaid, Landlord shall use, apply or retain all or any
portion of the proceeds thereof for (1) the payment of any Rent or any other
sums as to which Tenant is in default, (2) the payment of any amount which
Landlord may spend or become obligated to spend to repair damage to the Premises
or the Building for which repairs Tenant is liable hereunder, or (3)
compensation to Landlord for any losses which Landlord is entitled to recover
hereunder by reason of Tenant's Default, including, but not limited to, any
damage or deficiency arising in connection with the reletting of the Premises
and all associated reasonable legal fees. In the event that the Letter of Credit
is drawn upon by Landlord for failure of Tenant to renew said Letter of Credit
as aforesaid, the proceeds thereof shall be held by Landlord in accordance with
the provisions respecting the Security Deposit under this Section 35, and, in
such event, within thirty (30) days after the expiration of the Term, and
provided Tenant has vacated the Premises and is not in default hereunder,
Landlord shall return such proceeds to Tenant, less such portion thereof as
Landlord may be entitled hereunder to apply to satisfy any Default by Tenant
hereunder. In the event that Tenant is in default upon the expiration of the
Term and Landlord does not use all of the Security Deposit to cure such default,
then, after such default has been cured, Landlord shall return any unused
balance of the Security Deposit to Tenant. The use, application or retention of
the proceeds of the Letter of Credit, or any portion thereof, by Landlord shall
not prevent Landlord from exercising any other right or remedy provided by this
Lease or by law, and shall not limit any recovery to which Landlord may
otherwise be entitled. In the event of the sale or transfer of Landlord's
interest in the Building or the Land, Landlord shall transfer the proceeds of
the Letter of Credit to the purchaser or transferee, in which event Tenant shall
look only to the purchaser or transferee for the return of the proceeds of the
Letter of Credit, and Landlord shall be released from all liability to Tenant
for the return of such proceeds.

               B.   Transferability:  In the event of a sale or transfer of
Landlord's interest in the Building or of the interest of any successor or
assign of Landlord, Landlord (or such successor or assign) shall have the right
to transfer the Security Deposit to any vendee or transferee and shall thereupon
be released automatically from any liability therefor Tenant shall look solely
to the transferee for the return of the Security Deposit.  No Mortgagee or
purchaser of any or all of the Building at any foreclosure proceeding shall
(regardless of whether the Lease is at the time subordinated to the lien of said
Mortgage) be liable to Tenant or any other person for any of such Security
Deposit, or any other payment made by Tenant hereunder, unless Landlord has
actually delivered said deposit or other such sum to such Mortgagee or purchaser
in the event of any rightful and permitted assignment of Tenant's interest in
this Lease, the Security Deposit shall be deemed to be held by Landlord as a
deposit made by the assignee, and Landlord shall have no liability to the
assignor with respect to the return of the Security Deposit

          36.  HAZARDOUS MATERIALS

               A.   Definition.  As used in this Lease, the term "Hazardous
Material" means any flammable items, explosives, radioactive materials,
hazardous or toxic substances, material or waste or related materials, including
any substances defined as or included in the definition of "hazardous
substances", "hazardous wastes", "infectious wastes", "hazardous

                                       34
<PAGE>

materials" or "toxic substances", now or subsequently regulated under any
federal, state or local laws, regulations or ordinances including without
limitation, oil, petroleum-based products, paints, solvents, lead, cyanide, DDT,
printing inks, acids, pesticides, ammonia compounds and other chemical products,
asbestos, PCBs and similar compounds, and including any different products and
materials which are subsequently found to have adverse effects on the
environment or the health and safety of persons

               B.   General Prohibition.  Tenant shall not cause or permit any
Hazardous Material to be generated, produced, brought upon, used, stored,
treated, discharged, released, spilled or disposed of on, in under or about the
Premises, the Building, or the Land (hereinafter referred to collectively as the
"Property") by Tenant, its affiliates, agents, employees, contractors,
subtenants, assignees or invitees; provided, however, that such prohibition
shall not apply to fuel for Tenant's generators, batteries and customary office
and cleaning supplies, so long as all of same are stored, used and disposed of
in accordance with all applicable laws and governmental regulations.  Tenant
shall indemnify, defend and hold Landlord harmless from and against any and all
actions (including, without limitation, remedial or enforcement actions of any
kind, administrative or judicial proceedings, and orders or judgments arising
out of or resulting therefrom), costs, claims, damages (including without
limitation, attorneys', consultants', and experts' fees, court costs and amount
paid in settlement of any claims or actions), fines, forfeitures or other civil,
administrative or criminal penalties, injunctive or other relief (whether or not
based upon personal injury, property damage, or contamination of, or adverse
effects upon, the environment, water tables or natural resources), liabilities
or losses arising from a breach of this prohibition by Tenant, its affiliates,
agents, employees, contractors, subtenants, assignees or invitees.

               C.   Notice.  In the event that Hazardous Materials are
discovered upon, in, or under the Property, and any governmental agency or
entity having jurisdiction over the Property requires the removal of such
Hazardous Materials, Tenant shall be responsible for removing those Hazardous
Materials arising out of or related to the use or occupancy of the Property by
Tenant or its affiliates, agents, employees, contractors, subtenants, assignees
or invitees but not those of its predecessors.  Notwithstanding the foregoing,
Tenant shall not take any remedial action in or about the Property or any
portion thereof without first notifying Landlord of Tenant's intention to do so
and affording Landlord the opportunity to protect Landlord's interest with
respect thereto.  Tenant immediately shall notify Landlord in writing of: (i)
any spill, release, discharge or disposal of any hazardous Material in, on or
under the Property or any portion thereof; (ii) any enforcement, cleanup,
removal or other governmental or regulatory action instituted, contemplated, or
threatened (if Tenant has notice thereof) pursuant to any laws respecting
Hazardous Materials; (iii) any claim made or threatened by any person against
Tenant or the Property or any portion thereof relating to damage, contribution,
cost recovery, compensation, loss or injury resulting from or claimed to result
from any Hazardous Materials; and (iv) any reports made to any governmental
agency or entity arising out of or in connection with any Hazardous Materials
in, on under or about or removed from the Property or any portion thereof,
including any complaints, notices, warnings, reports or asserted violations in
connection therewith.  Tenant also shall supply to Landlord as promptly as
possible, and in any event within five (5) business days after Tenant first
receives or sends the same, copies of all claims, reports, complaints, notices,
warnings or asserted violations relating in any way to the Premises, the
Property or Tenant's use or occupancy thereof.

                                       35
<PAGE>

               D.   Survival.  The respective rights and obligations of Landlord
and Tenant under this Section 36 shall survive the expiration or earlier
termination of this Lease.

          37.  RELOCATION OF TENANT [Intentionally omitted.].

          38.  MEMORANDUM OF LEASE.

          A Memorandum of Lease (i) referring to this Lease, including, but not
limited to, the names of the parties, the description of the Land, the Term, a
statement regarding the use of the Premises, and such other provisions hereof as
Landlord and Tenant shall mutually approve, and (ii) in the form attached hereto
and made a part hereof as Exhibit 1, shall, at Tenant's or Landlord's request,
be executed by Landlord and Tenant and recorded among the Land Records in the
Circuit Court of Loudoun County, Virginia, in which case the party requesting
such recordation shall pay all recordation fees, taxes and charges which are
assessed by the recording official.

          39.  ANTENNA LICENSE.

          Subject to the terms of this Section 39, Landlord hereby grants to
Tenant a license during the Term provided that Tenant is not in default under
this Lease: to install and operate a reasonable number of satellite dishes
(solely for Tenant's business as conducted within the Premises, and not for any
resale or other commercial purpose, except for use by Customers (as hereinafter
defined in Paragraph 7 of Exhibit G hereto)), microwave antennae and other
similar equipment in and on the Building in accordance with specifications and
at locations approved by Landlord in writing in advance, in Landlord's sole
discretion (all of the foregoing items being hereinafter collectively referred
to as the "Equipment").

          The installation of the Equipment shall be performed only by
contractors which are bonded, licensed, insured and reputable.

          In the event Tenant undertakes installation of any Items of the
Equipment, Tenant shall not be obligated to pay any fee or rental with respect
to the use of the roof for the Equipment which is in addition to the Base Rent
or the Additional Rent which is provided for in Section 5 hereof.

          This Section 39 shall be subject at all times to the following
conditions (the failure of any of which shall be a material breach of this
Section 39 by Tenant and shall give Landlord the right to terminate Tenant's
access and use of the roof for said Equipment):

                    (a)  The Equipment shall be installed and at all times
operated, maintained and repaired by Tenant, at Tenant's sole cost and expense.
All penetrations into any of the Building surfaces shall be sealed so as to
prevent any water leakage. Tenant shall not undertake or engage in any
installation of the Equipment without first submitting to Landlord detailed
working plans of all such installations and obtaining prior written approval of
Landlord.

                    (b)  Throughout the period of such installation, and
thereafter during any operation, maintenance or repair of the Equipment, Tenant
shall install and utilize, at Tenant's sole expense, such screening supports,
walk boards, and such other materials as may be

                                       36
<PAGE>

required by Landlord to protect the Building or any part thereof, the Building
generally, pedestrians, vehicles on adjacent roadways and any other property or
owners of property adjacent to the Building.

                    (c)  The Equipment installed or operated by Tenant hereunder
shall be installed, operated, maintained and repaired by Tenant in a good and
workmanlike manner and in a manner which shall not impair the structure, value,
rental value or rentability of, or detract from the appearance of, the Building
or any part thereof.

                    (d)  The Equipment installed or operated by Tenant hereunder
shall be installed, operated, maintained and repaired by Tenant in a manner
which shall not cause a violation of any mortgage, deed of trust, ground lease
or other financing instrument now existing or hereafter recorded with respect to
the Building at any time after Landlord has provided Tenant with notice of the
applicable provisions thereof, or any agreements or warranties with respect to
the Building or any part thereof as are now or hereafter shall be held by or
entered into by Landlord or Landlord's management agent. The provisions of this
Section 39(d) shall not apply to any mortgage, deed of trust, ground lease or
financing instrument, the provisions of which would preclude Tenant from
exercising its right to install Equipment pursuant to this Section 39.

                    (e)  The Equipment installed or operated by Tenant hereunder
shall be installed, operated, maintained and repaired by Tenant in a manner
which shall not interfere with or disturb any tenant or other occupant of the
Park.

                    (f)  The Equipment shall not cause interference with any
other equipment of any nature in, on or about the Building or the Park or any
other equipment owned by any other person, irrespective of where located and
irrespective of whether such person has any interest in the Park. In the event
that the Equipment causes such interference, Tenant agrees it will take all
steps necessary to correct and eliminate the interference consistent with
appropriate government rules and regulations upon receipt of written
notification of the interference. If Tenant does not commence to eliminate the
interference within one (1) calendar day after receipt of notification, or if
the interference is not in fact eliminated within two (2) business days of
receipt of notification, Tenant will cease operation of the equipment causing
such interference until such interference is cured.

                    (g)  Neither the Equipment nor Tenant shall unreasonably
interfere with the use of the roof of the Building by Landlord.

                    (h)  Prior to the installation of the Equipment, Tenant
shall obtain, and shall thereafter comply with and keep in force throughout the
Term, all permits, licenses, inspections and other governmental requirements and
authorizations required by all governmental authorities having jurisdiction over
the Building, the Equipment, Tenant, or the business operations in which the
Equipment shall be utilized.

                    (i)  The installation, operation, maintenance and repair of
the Equipment shall be performed by Tenant in accordance with all applicable
laws, regulations and

                                       37
<PAGE>

other requirements of all federal and local government and quasi-governmental
entities and authorities.

          Tenant acknowledges and agrees that Landlord has not made any
representation, warranty or other statement to Tenant (and none is implied)
regarding the feasibility of installing or operating the Equipment hereunder.

          Landlord agrees to permit Tenant reasonable, non-exclusive access to
portions of the Building as necessary so as to facilitate the installation,
operation, maintenance, repair, and removal of the Equipment in accordance with
this Section 39.

          40.  OPTIONS TO EXTEND.

          Provided that Equinix, Inc., a Delaware corporation, or an Affiliate
(as defined in Section 23.A. hereof) (said Equinix, Inc. or an Affiliate being
hereinafter collectively referred to as "Equinix") (i) is not then in default in
the payment of any Rent due under this Lease and is not then in Default in the
performance of any of its other obligations under this Lease, and (ii) has not
been in Default more than once during the immediately preceding two (2) years of
the Term, in each case both at the time of exercise of the Renewal Option, as
hereinafter defined, in question, and at the commencement of the Renewal Period,
as hereinafter defined, in question, and is then in occupancy of the Premises at
the time of exercise of the Renewal Option, as hereinafter defined, in question,
and at the time of the commencement of the Renewal Period, as hereinafter
defined, in question, Equinix shall have three (3) successive options (the
"Renewal Options") to extend the Term of the Lease, each for a successive
additional five (5) year period (the "Renewal Periods") after the expiration of
the Initial Term.  Each Renewal Option shall be exercisable only by written
notice given by Equinix to Landlord not later than twelve (12) months, nor
earlier than fifteen (15) months, prior to the expiration of the initial Term,
or the Renewal Period then in effect, as the case may be.  In the event that
Equinix does not timely exercise a Renewal Option, said Renewal Option and all
successive Renewal Options shall be null and void and of no further force or
effect, time being of the essence in the exercise of each Renewal Option and it
being acknowledged and agreed by Equinix that Landlord shall be entitled to rely
on any failure by Equinix to give written notice of its exercise of its Renewal
Option by the date set forth herein for such exercise thereof.

          All terms and conditions of this Lease shall be applicable during the
Renewal Period except that the amount of Base Rent charged for each Renewal
Period shall be the then "Prevailing Market Rent", which shall be the rent for
comparable space in comparable buildings in Loudoun County, Virginia; provided,
however, that in no event shall the Prevailing Market Rent determined as
aforesaid be deemed to be less than the Base Rent payable under this Lease
during the Lease Year immediately preceding the first Lease Year of the Renewal
Period.  If within thirty (30) days following delivery of Equinix's notice,
Landlord and Equinix have not mutually agreed on the Prevailing Market Rent for
the Renewal Period in question, then within ten (10) days after the expiration
of such thirty-day period, each party shall file written notice to the other
setting forth the name and address of a Broker (as hereinafter defined) selected
by such party who has agreed to act in such capacity, to determine the
Prevailing Market Rent.  If either party shall fall to select a Broker as
aforesaid, the Prevailing Market Rent shall be determined by the Broker selected
by the other party.  Each Broker shall thereupon independently make his

                                       38
<PAGE>

determination of the Prevailing Market Rent within twenty (20) days after the
appointment of the second Broker.  If the two Brokers' determinations are not
the same, but the higher of such two values is not more than one hundred five
percent (105%) of the lower of them, then the Prevailing Market Rent shall be
deemed to be the average of the two values.  If the higher of such two values is
more than one hundred five percent (105%) of the lower of them, then the two
Brokers shall jointly appoint a third Broker within ten (10) days after the
second of the two determinations described above has been rendered.  The third
Broker shall independently make his determination of the Prevailing Market Rent
within twenty (20) days after his appointment.  The highest and the lowest
determinations of value among the three Brokers shall be disregarded and the
remaining determination shall be deemed to be the Prevailing Market Rent.
Within thirty (30) days after the Prevailing Market Rent is determined as
aforesaid, the parties shall execute an amendment to this Lease setting forth
the new Rent to be paid for the Renewal Period.

          For the purposes of this Section 40, "Broker" shall mean a real estate
broker licensed in the Commonwealth of Virginia, who has been regularly engaged
in such capacity in the business of commercial leasing in Loudoun County,
Virginia for at least ten (10) years immediately preceding such person's
appointment hereunder.  Each party shall pay for the cost of its Broker and one-
half of the cost of the third Broker.

                                       39
<PAGE>

          IN WITNESS WHEREOF, Landlord and Tenant have executed this Deed of
Lease under seal as of the day and year first above written.

WITNESS:                                   LANDLORD:

                                           TRIZECHAHAN CENTERS, INC. dba
                                           TrizecHahn Beaumeade Corporate
                                           Management, a California corporation
By: _____________________________          By: ________________________________
                                           Name: ______________________________
                                           Its: _______________________________

ATTEST:                                    TENANT:

[Corporate Seal]                           EQUINIX, INC., a Delaware corporation
By:  /s/ Jay S. Adelson                    By:  /s/ Philip J. Koen
     ----------------------------               -------------------------------
Name:  Jay S. Adelson                      Name:   Philip J. Koen
       --------------------------                  ----------------------------
Its:  Chief Financial Officer              Its:  Chief Financial Officer
      --------------------------                 ------------------------------

                                       40
<PAGE>

                                   EXHIBIT A

                        [Graphic of Layout of Premises]

                                      A-1
<PAGE>

                                    EXHIBIT B

                      DECLARATION BY LANDLORD AND TENANT
                   AS TO DATE OF DELIVERY AND ACCEPTANCE OF
                   POSSESSION, LEASE COMMENCEMENT DATE, ETC.

          THIS DECLARATION is hereby attached to and made a part of the Deed of
Lease dated the __________ day of __________, 1999 (the "Lease"), entered into
by and between TRIZECHAHN CENTERS, INC. dba TRIZECHAHN BEAUMEADE CORPORATE
MANAGEMENT, a California corporation, as Landlord and EQUINIX, INC., a Delaware
corporation, as Tenant.  All terms used in this Declaration have the same
meaning as they have in the Lease.

          (i)   Landlord and Tenant do hereby declare that possession of the
Premises was accepted by Tenant on the ___ day of __________, 19___;

          (ii)  As of the date hereof, the Lease is in full force and effect,
and Landlord has fulfilled all of its obligations under the Lease required to be
fulfilled by Landlord on or prior to said date;

          (iii) The Lease Commencement Date is hereby established to be
__________________, 19___; and

          (iv)  The Lease Expiration Date is hereby established to be
_______________________, unless the Lease is sooner terminated pursuant to any
provision thereof.

WITNESS:                           LANDLORD:

                                   TRIZECHAHN CENTERS, INC. dba TrizecHahn
                                   Beaumeade Corporate Management, a
                                   California corporation
By:__________________________      By:_____________________________________
                                   Name:___________________________________
                                   Its:____________________________________

ATTEST:                            TENANT:

[Corporate Seal]                   EQUINIX, INC., a Delaware corporation

By:__________________________      By:_____________________________________
Name:________________________      Name:___________________________________
Its:_________________________      Its:____________________________________

           [NOTE: NOT TO BE EXECUTED AT TIME OF EXECUTION OF LEASE]
                  ---

                                      B-1
<PAGE>

                                  EXHIBIT C-1

Outline Specifications for [*] Building F
[*], Virginia

TECHNICAL SECTIONS
--------------------------------------------------------------------------------
                                                               23 September 1999
DIVISION 1 GENERAL REQUIREMENTS

1010  -    SUMMARY OF THE WORK

           The project consists of a one-story base building structure and
           related site and utility development on a previously undeveloped
           suburban tract in [*] near Dulles, Virginia, The site is
           approximately 9.0 acres of land. The building shall be rectangular in
           shape with outside dimensions of [*] for approximately [*] gsf. The
           site will have approximately 360 parking spaces provided. The
           structure is a tilt-up concrete frame with steel columns with joist
           girders and bar joists supporting the roof. The majority of the
           facade shall be articulated with revels and minimum punched windows
           at the entrances. The building height will be approximately 30' with
           24' clear to underside of joist. Glazing shall be insulated and dark
           bronze tint. Bronze spandrel panel shall be utilized for all glazing
           above 10'. Service and loading areas shall be located on a rear
           facade, as well as a specially designed generator enclosure area. The
           front, sides and rear parking area are landscaped as required. Assume
           3 non-motorized overhead dock doors (12' x 14').

1020   -   ALLOWANCES

           [_] Per Owner direction, allowances will be quoted for specifically
           identified items.

01026  -   UNIT PRICES

01030  -   ALTERNATES

01035  -   MODIFICATION PROCEDURES

01040  -   PROJECT COORDINATION

           The contractor is responsible for all the components that are
           necessary parts-of full and complete building systems per design
           intent. All subparts of any building system or any part reasonably
           inferable there from shall be considered part of the Architect's or
           Engineer's drawings and would be assumed to be part of this contract
           for construction.
________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                     C-1-1
<PAGE>

01050  -    FIELD ENGINEERING

            [_] The contractor shall be responsible for building layout and
            staking. Restaking, stake displacement, and any related activity due
            to contractor errors shall be the responsibility of the contractor.

01090  -    DEFINITIONS AND STANDARDS

01300  -    SUBMITTALS

01310  -    SCHEDULES, REPORTS, PAYMENTS

01340  -    SHOP DRAWINGS, PROD. DATA, AND SAMPLES

01400  -    QUALITY CONTROL SERVICES

            [_] Life Safety Provisions: BOCA 1996, ADA and Commonwealth of
            Virginia Labor and Industrial Standards apply. Testing of soils,
            concrete and steel connections are among construction testing
            required. All testing services supplied by Owner.

01500  -    TEMPORARY FACILITIES

01600  -    MATERIAL AND EQUIPMENT

01631  -    PRODUCT SUBSTITUTIONS

01700  -    PROJECT CLOSEOUT

01740  -    WARRANTIES AND BONDS

DIVISION 2 - SITEWORK

02110  -    SITE CLEARING

            [_] Service court accommodating trucks will also be included. Site
            drainage will be to an existing regional management system.

02200  -    EARTHWORK

            [_] The intent of this project is to make the excavation an
            unclassified bid. Identify lump sum prices for overall earthwork as
            well as costs for individual work items.

                                       2
<PAGE>

02422  -    IRRIGATION

            [_] All planting and lawn areas immediately adjacent to the building
            shall be irrigated with an automatic underground irrigation system.
            Materials and installation shall conform to all requirements of park
            covenants and local jurisdiction and the Commonwealth of Virginia
            water, sewer and electrical requirements. Covenants for park will
            also apply.

02480  -    LANDSCAPING
            [_] All plant material shall meet or exceed the American
            Nurseryman's Association (AAN) and Commonwealth of Virginia
            Standards. All planting means and methods shall conform to ASLA
            standards of practice. Plants shall be installed per proper and
            recognized procedures for the climate of Chantilly, Virginia and
            indigenous to area. All plant materials shall be guaranteed for one
            year from the date of Final Acceptance. Park covenants must be
            followed. Detailed plantings will be provided at building entrances.
            Trees will border entrances and parking islands. All lawns and open
            areas will be seeded or covered with ground cover. Property lines
            will be buffered with plant material.

02481  -    LAWNS

            [_] All seed and sod shall meet applicable Commonwealth of Virginia
            Standards and shall be certified by the local Turf Growers
            Association. Installation of lawns shall be in accordance with the
            ASLA. Guarantee all lawns until acceptance.

02483  -    SIGNAGE COORDINATION

            [_] All exterior signage for the site must conform to the covenants,
            regulations and zoning restrictions of the park as well as local
            codes.

02513  -    ASPHALT CONCRETE PAVING (Final sections will be base on geotechnical
            report) [_] Car Parking Paving Detail: 3" base course, 1 1/2 "
            surface course of asphaltic concrete on 6" of crushed stone. Include
            parking stripes. Heavy-duty Paving Detail: 4: base course, 2"
            surface course of asphaltic concrete on 6" of crushed stone. Include
            lane stripes. Final design to be used is to be based on actual CBR
            Valves obtained by on-site testing.

02520  -    Concrete Paving

            [_] Local jurisdiction requirements and ACI standards shall apply.
               Curbs will be continuous at site and building entrances and
               comply with ADA.

                                       3
<PAGE>

02660  -    POTABLE WATER SYSTEMS

            [_] Provide per local county standards. Hook-up fees are the
            responsibility of the contractor.

02720  -    STORM SEWER SYSTEMS

            [_] Both surface swale systems and underground conduit systems will
            direct run-off water to a regional facility.

DIVISION 3 - CONCRETE

03310  -    CONCRETE

            [_] Individual reinforced concrete spread footings shall be used in
            accordance with test results from borings. The slab on grade will be
            a rebar reinforced 6"-3500 psi concrete slab. All spread footings
            and grade beams shall be 3000 psi concrete. Concrete slab shall be
            designed for load capacity of 250 psf, F.F. = 20, F.L.= 15.

03410  -    TILT-UP CONCRETE PANELS

            [_] Tilt-up concrete panels will be cast in modular shapes and
            poured on site. Panels to be engineered for load bearing duty at
            exterior wall. Panels will be finished with the Tex-coat (XL-70)
            system with medium texture finish. The tilt panels will be
            moderately articulated and configured with punched opening for
            windows. Proper bond breakers and fiberglass reveals shall be used.
            All panels are to be priced as 8" thick, 4000 psi concrete, or as
            per final engineering documents.

DIVISION 4 - MASONRY

04200  -    UNIT MASONRY

            [_] Masonry walls shall be used to enclose the electrical and
            sprinkler rooms to 10' AFF. Mortar: All mortar to be field mixed
            Portland Cement-Lime type. Type S for exterior and bearing walls,
            and Type M below grade. Conforming to ASTM C270. Color to be
            selected from standard colors and equal to "Colorport" by Riverton
            Corporation.

DIVISION 5 - METALS

05200  -    STRUCTURAL STEEL

            [_] Bar joist and joist girders shall be used to support the roof.
            Roof deck shall be 1-1/2" Type B painted roof deck. The standard
            structural bay shall be approximately 45' x 40'.

                                       4
<PAGE>

05210  -    STEEL JOISTS/JOIST GIRDERS

            [_] Structural system shall employ bar joists and joist girders for
            roof construction only. Steel columns shall provide vertical
            support. The roof structure shall be designed for 25-lb. dead load
            and 30-lb. live (snow) load. The roof joists and girders along the
            second bay back from the front facade shall be upgraded to
            accommodate future rooftop units.

05500  -    METAL FABRICATIONS

            [_] Exit stairs shall be fabricated with steel channels and concrete
            filled metal pans. Provide two 4' x 3-1/2" dia. concrete filled
            bollards at each at each service door. Provide 4" x 4" x 1/4" steel
            angle door guards to 4'.

05521  -    PIPE AND TUBE RAILINGS

            [_] Painted pipe railings to be used at all exit stairways. Rails
            shall be 1-1/2" diameter painted steel tubes. All stairs shall
            provide guardrails to 42" above tread and handrails at 34" above
            tread. All guardrails shall have 1/2 diameter vertical balusters at
            4.5" o.c.

DIVISION 6 - WOOD AND PLASTICS

06100  -    ROUGH CARPENTRY

06200  -    FINISH CARPENTRY

DIVISION 7 - THERMAL AND MOISTURE PROTECTION

07190  -    VAPOR BARRIERS

            [_] Polyurethane sheets 6 mil. to be used under grade slab.

07200  -    INSULATION

            [_] Roof insulation shall be R-l9 utilizing Polyisocyanurate
            insulation. Alternate shall be R-19 EPS insulation with thermal
            barrier (3/4" Fresco board). Fire safety insulation to be used as
            per BOCA 1996, and local county code. Landlord to provide insulation
            as necessary to obtain permits for a shell building to meet energy
            envelope requirements. Wall insulation shall be tenant supplied.
            Slab insulation shall be R-7.5 utilizing 2" rigid boards and limited
            to within 4' of slab edge (run horizontally and vertically) at the
            perimeter.

                                       5
<PAGE>

07530  -    FLEXIBLE SHEET ROOF SYSTEMS

            [_] EPDM single ply (45 mil) ballasted roofing system shall be
            installed with 10-year warranty. Roof membrane will be ballasted
            with smooth river run gravel of 3/4" minimum and 2" maximum
            diameter. Coverage shall be even. Ballast shall be provided at a
            rate of 12 psf for the remaining roof area Roof will utilize
            Termination bar detail per standard manufacturer detail.

07600  -    FLASHING AND SHEET METAL

07620  -    METAL FASCIA AND COPING

07700  -    ROOF SPECIALTIES & ACCESSORIES

            [_] Ladder access shall be provided to the roof. The roofing
            manufacturer's standards shall be followed for all roof penetrations
            of conduit and supports for satellite antenna, etc. Walkways to be
            precast pavers (2'x2'x2') to run from roof hatch to each roof top
            unit. ( To be supplied by tenant during tenant construction.)

07900  -    JOINT SEALERS

            [_] Joint sealers shall be of a custom color where visible from
            exterior and generally match the exterior wall color. Product
            selections shall depend upon application. Acceptable companies shall
            include Tremco. All precast panels shall be caulked with backer rods
            at two locations (outside edge and inside edge) as well as for each
            top. All panels shall be painted first and then the joints shall be
            sealed. GC shall take necessary precautions to prevent texture paint
            from entering joint and preventing a proper seal.

DIVISION 8 - DOORS AND WINDOWS

08110  -    STEEL DOORS AND FRAMES

            [_] Exterior insulated, 20 ga. face steel doors (3'-0" x 7'-0" x 1-
            3/4") and frames 16 ga. (welded with 2" trim) will be used at
            utility rooms and for exit doors. Painted steel frames will be used
            for all other base building interior conditions. All fire doors
            shall carry UL label for entire door frame assembly.

08333  -    OVERHEAD DOORS

            [_] Sectional overhead doors shall be 12' x 14' insulated metal
            doors with steel frames. Provide each sectional overhead door as a
            complete unit produced by one manufacturer, Thermacore 190 (or
            equal)). All doors to be operated mechanically unless otherwise
            specified.

                                       6
<PAGE>

08410  -    ALUMINUM ENTRANCE DOORS

            [_] Black anodized Kawneer #190 doors or equal with dark bronze
            steel horizontal push bars and CS9 bright stainless steel vertical
            pull bars will be used at entry doors and other public access doors
            throughout the project. These doors "will be glazed with 1/4" non-
            insulated safety glazing. Provide latch paddle device. Entry doors
            to have concealed closures. Thresholds shall be similar light metal
            finish (brushed aluminum)

08525  -    ARCHITECTURAL ALUMINUM WINDOWS

            [_] Kawneer 450 (or equal) glazing system will be used for windows.
            Color shall be permanodic Kawneer (or equal) black.

08710  -    FINISH HARDWARE

            [_] The building hardware metal color shall be white (stainless
            steel for exterior doors or bright chromium plated for interior
            doors). Hardware noted is by Schlage (625 finish) (or equal) and
            handicap rated: Latchsets to be Athens (ATM) D10S, Locksets to be
            Athens (ATM) D50PD, Mortised deadbolts where required, Deadbolts to
            be B460P, 6 pin tumblers, Thresholds to be brushed aluminum at
            entryway, exits, labeled doors and loading areas with maximum 1/2"
            rise.

08800  -    GLASS AND GLAZING (To match buildings A-E)

            [_] The building glazing shall be l" insulated ( 1/4" Glass, 1/2"
            Airspace, 1/4" Glass) and lightly tinted. Glass shall be bronze
            tinted. Spandrel glazing shall be AFGD Clear with Solex Frit, EX-26-
            111 (bronze) or equal. Tinted 1/4" safety glazing shall be used for
            entry doors. Glass adjacent to entry doors shall be safety glazing.
            All glass to meet local Jurisdiction's and Commonwealth of Virginia
            codes.

                                       7
<PAGE>

DIVISION 9 - FINISHES

09250  -    GYPSUM DRYWALL

            [_] Base building electrical and sprinkler-demising partitions shall
            utilize USG gypsum board standards from 10' aff to roof deck. A
            construction joint shall be placed to break up each expansion of 25'
            or more of gypsum wall. Deflection joints to be provided at all stud
            walls extending to underside of structure or roof deck.

09512  -    ACOUSTICAL TILE CEILINGS (N/A)

09651  -    RESILIENT FLOOR MOULDING (N/A)

09653  -    RESILIENT BASE MOULDING (N/A)

09680  -    CARPET (N/A)

09900  -    PAINTING

            [_] Miscellaneous metals including exterior stairs

DIVISION 10 - SPECIALTIES

10155  -    TOILET COMPARTMENT (N/A)

10522  -    FIRE EXTINGUISHERS, CABINETS & ACCESSORIES

            [_] Provide surface mounted fire extinguishers per local code
            requirements for a shell building.

10801  -    TOILET & BATH ACCESSORIES (N/A)

DIVISION 11 - EQUIPMENT

11160  -    LOADING DOCK EQUIPMENT (By tenant, listed is TrizecHahn standard)

            [_] Dock Levelers: Provide (1) To be fully mechanical, requiring no
            manual lifting to operate. To be spring counter balanced. Lip to
            automatically extend. Hinged legs to provide full rated capacity
            support at dock level. To allow lowering of ramp below dock level
            without exceeding lip. To meet U.S. Department of Commerce Standard
            C.S. 202-S6. Dock levelers shall be 6x6, 25,0001b. capacity. Kelley
            Company, model M606C.

            [_] Dock Bumpers: Dock bumpers shall be furnished and installed by
            Contractor.

                                       8
<PAGE>

DIVISION 12 - FURNISHINGS

12511  -  HORIZONTAL LOWER BLINDS

12680  -  FOOT GRILLES

          [_] No provision for recessed walk off mat

DIVISION 15 - MECHANICAL

15010  -  BASIC MECHANICAL REQUIREMENTS

15050  -  BASIC MECHANICAL MATERIALS AND METHODS

15055  -  BASIC PIPING MATERIALS AND METHODS

15250  -  MECHANICAL INSULATION

15300  -  FIRE PROTECTION

15411  -  WATER DISTRIBUTION PIPING

15420  -  DRAINAGE AND VENT SYSTEMS

15440  -  PLUMBING FIXTURES

          [_] Equipment to include standpipe riser, valves, fire pump, sprinkler
          mains, annunciator, fire controls as required by code. Building shell
          systems shall be designed and sized for office use. Main distribution
          of the sprinkler line shall extend throughout a mutually agreed upon
          elevation. Sprinkler heads oriented per Fire Marshall instructions.
          Provide sprinkler system with full coordination with structure and
          NFPA 231C, Commodity 4 code. Provide a 6" sanitary line running the
          entire building length. Provide water mains and meters for domestic
          water service and fire service to building.

          [_] Rainwater leaders shall be internalized on the outside walls with
          underground (under slab) laterals. Drain overflows will be scuppered
          to day light at building. All overflow leaders and roof leaders shall
          be separate from the drains to the under slab lateral in accordance
          with the plumbing codes.

15781  -  PACKAGED HEATING AND COOLING UNITS.

          [_] Provide heating units in the electrical and sprinkler rooms to
          provide freeze protection. All other unit heaters and rooftop HVAC
          units shall be part of the tenant improvement contract.

15850  -  AIR HANDLING

15891  -  AIR OUTLETS AND INLETS

                                       9
<PAGE>

15933  -  AIR TERMINALS

15971  -  CONTROL SYSTEMS

          [_] All building systems and construction will be designed to meet all
          applicable local, state and federal codes and regulations.

15990  -  TESTING, ADJUSTING AND BALANCING

DIVISION 16 - ELECTRICAL

16010  -  BASIC ELECTRICAL REQUIREMENTS

          [_] Exterior lighting in the parking areas shall provide and average
          or 1.5 foot candles for security and nighttime visibility. Metal
          halide lamps shall be used on the building and parking light poles.
          All poles and light fixtures shall conform to Beaumeade Technology
          Park standards or approved equal.

16110  -  RACEWAYS

16120  -  WIRES AND CABLES

16145  -  WIRING DEVICES

16170  -  CIRCUIT AND MOTOR DISCONNECTS

16425  -  MAIN SWITCHBOARDS

16452  -  GROUNDING

16460  -  TRANSFORMERS (To be Coordinated with Tenant)

          [_] Pad mounted transformer Primary underground service 2000 amp,
          277/480 volt, 3 phase, 4 wire. Calculation to assume 3 watts for
          lighting and 6 watts for office equipment power.

          [_] Main switch with ground fault protection to be provided per code
          requirements at switchboard, with fusible branch devices. Emergency
          and exit lighting in accordance with local code requirements.

16470  -  PANEL BOARDS (To be coordinated with Tenant)

          [_] 277/480 volt, cable in conduit risers to connect main switch gear
          to panels in electrical room. The electrical room shall have house
          panel boards a minimum of 277/480 volts serving site lighting, minimum
          indoor lighting and emergency lighting and sprinkler room
          requirements. Through capacity for additional four sub-panels for
          future tenants shall also be provided.

                                      10
<PAGE>

16512  -  EXTERIOR LIGHTING FIXTURES

          [_] 400 watt HID high-pressure sodium wall mounted fixtures shall be
          provided at truck court. 400 watt HID high-pressure sodium pole
          mounted fixtures shall be provided in parking areas. Maintain an
          average of 1.5 foot-candles at grade. All exterior lighting shall be
          on a photocell switch.

16515  -  INTERIOR LIGHTING FIXTURES (To be Coordinated with Tenant)

          [_] Warehouse lighting will by metal halide, 400W every other bay.

16621  -  EMERGENCY POWER ELECTRICAL SYSTEMS

16721  -  FIRE ALARM SYSTEMS

          Minimum required to meet county code.

END OF OUTLINE SPECIFICATION

                                      11
<PAGE>

                                  EXHIBIT C-2

                 [Graphic of Chart Describing Project Schedule]

                                     C-2-1
<PAGE>

                                  EXHIBIT D-1

                             RULES AND REGULATIONS

          The following rules and regulations have been formulated for the
safety and well-being of all the tenants of the Park.  Adherence to these rules
and regulations by each and every tenant contributes to safe occupancy and quiet
enjoyment of the Park.  Any violation of these rules and regulations by any
tenant which continues after notice from Landlord shall be a Default under such
tenant's lease, at the option of Landlord.

          Landlord may, upon request by any tenant, waive compliance by such
tenant of any of the following rules and regulations, provided that (a) no
waiver shall be effective unless signed by Landlord or Landlord's authorized
agent, (b) no such waiver shall relieve any tenant from the obligation to comply
with such rule or regulation in the future, unless expressly consented to by
Landlord, and (c) no such waiver granted to any tenant shall relieve any other
tenant from the obligation of complying with said rule or regulation unless such
other tenant has received a similar waiver in writing from Landlord.

          1.   The sidewalks, entrances, passages, courtyards, elevators,
vestibules, stairways, corridors, halls and other parts of the Park not occupied
by any tenant (hereinafter "Common Areas") shall not be obstructed or encumbered
by any tenant or used for any purposes other than ingress and egress to and from
the tenant's premises.  No tenant shall permit the visit to its premises of
persons in such numbers or under such conditions as to interfere with the use
and enjoyment of the Common Areas by other tenants.

          2.   No awnings or other projections shall be attached to the outside
walls of the Building without the prior written consent of Landlord.  No drapes,
blinds, shades or screens shall be attached to or hung in, or used in connection
with, any window or door of a tenant's premises, without the prior written
consent of Landlord.  Such awnings, projections, curtains, blinds, screens and
other fixtures shall be of a quality, type, design and color acceptable to
Landlord and shall be attached in a manner approved by Landlord.

          3.   No sign, advertisement, notice or other lettering shall be
exhibited, inscribed, painted or affixed by any tenant on any part of the
outside or inside of the tenant's premises or in the Park without the prior
written consent of Landlord.  In the event of any violation of the foregoing by
any tenant, Landlord may remove the same without any liability and may charge
the expense incurred by such removal to the tenant or tenants responsible for
violating this rule.  All exterior signs on the doors of the Building Park shall
be inscribed, painted or affixed by Landlord at the expense of each tenant, and
shall be of a size, color and style acceptable to Landlord.

          4.   No show cases or other articles shall be put in front of or
affixed to any part of the exterior of the Building, nor placed in the Common
Areas without the prior written consent of Landlord.

          5.   The water and wash closets and other plumbing fixtures shall not
be used for any purposes other than those for which they were constructed, and
no sweepings, rubbish,

                                     D-1-1
<PAGE>

rags or other substances shall be thrown therein. No tenant shall throw anything
out of the doors or windows or down any corridors of stairs.

          6.   No tenant shall construct, maintain, use or operate on the
outside of the Building, any electrical device, wiring or apparatus in
connection with a loud speaker system or other sound system.  Tenant may install
Muzak or other internal music system within the tenant's premises if the music
system cannot be heard outside of the premises.

          7.   No tenant shall make or permit to be made any disturbing noises
or disturb or interfere with the occupants of the Park or those having business
with them, whether by the use of any musical instrument, radio, tape recorder,
whistling, singing or any other way.

          8.   No bicycles, vehicles, animals, birds or pets of any kind shall
be brought into or kept in or about a tenant's premises or in the Park.

          9.   [Intentionally omitted.]

          10.  No space in or about the Building shall be used for the
manufacture, storage, sale or auction of merchandise goods or property of any
kind.

          11.  [Intentionally omitted.]

          12.  Tenant shall allow Landlord access to the Premises in accordance
with the terms and conditions of the Lease, including, but not limited to,
Section 11 thereof.  Each tenant shall, upon the termination of its tenancy,
return to Landlord all keys used in connection with its premises, including any
keys to the premises, to rooms and offices within the premises, to storage rooms
and closets, to cabinets and other built-in furniture, and to toilet rooms,
whether or not such keys were furnished by Landlord or procured by the tenant,
and in the event of the loss of such keys, such tenant shall pay to Landlord the
cost of replacing the locks.  On termination of a tenant's lease, the tenant
shall disclose to Landlord the combination of all locks for safes, safe cabinets
and vault doors, if any, remaining in the premises.

          13.  [Intentionally omitted.]

          14.  [Intentionally omitted.]

          15.  No tenant shall purchase spring water, ice, coffee, soft drinks,
towels or other like merchandise or service from any company or person who has,
in Landlord's opinion committed violations of Park regulations or caused a
hazard or nuisance to the Park and/or its occupants.

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

          17.  Landlord reserves the right to exclude from the Park at all times
any person who is not known or does not properly identify himself to the Park's
management or its

                                     D-1-2
<PAGE>

agents. Each tenant shall be responsible for all persons for whom it authorized
entry into the Building, and shall be liable to Landlord for all acts of such
persons.

          18.  [Intentionally omitted.]

          19.  The requirements of tenants will be attended to only upon
application at the office of the Park.  Park employees have been instructed not
to perform any work or do anything outside of their regular duties, except with
special instructions from the management of the Park.

          20.  Canvassing, soliciting and peddling in the Park is prohibited,
and each tenant shall cooperate to prevent the same.

          21.  [Intentionally omitted.]

          22.  [Intentionally omitted.]

          23.  Access plates to under floor conduits shall be left exposed.
Where carpet is installed, carpet shall be cut around the access plates.

          24.  [Intentionally omitted.]

          25.  [Intentionally omitted.]

          26.  [Intentionally omitted.]

          27.  Landlord's employees are prohibited from receiving articles
delivered to the Park and, if any such employee receives any article for any
tenant, such employee shall be acing as the agent of such tenant for such
purposes.

          28.  All cigarettes and related trash shall be disposed of in trash
receptacles and not on the sidewalk, parking lot or grass.

                                     D-1-3
<PAGE>

                                  EXHIBIT D-2

                   DECLARATIONS OF PROTECTIVE COVENANTS [*]

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                     D-2-1
<PAGE>

                      DECLARATION OF PROTECTIVE COVENANTS

                                      [*]
                           ------------------------

THIS CORRECTED DECLARATION OF PROTECTIVE COVENANTS FOR [*] (the "Declaration")
is made by Beau Meade Associates, a Maryland general partnership, owner of
record of the real property shown on the plat attached hereto as Exhibit A
(hereinafter referred to as "Declarant").

                                  WITNESSETH:
                                  ----------

          Declarant, for the use and benefit of itself and its successors and
assigns, does hereby place and impose upon those certain parcels of real
property hereinafter described the following conditions, covenants,
reservations, easements and restrictions, for the mutual benefit of Declarant
and all Owners (hereinafter defined), to insure the proper use, appropriate
development and improvement of such property; to protect against the
construction of improvements and structures built of improper or unsuitable
materials; to insure compliance with all applicable zoning ordinances, building
codes and environmental laws and regulations; to provide for a method for the
maintenance and continued improvement of certain common areas and facilities
appurtenant to such property; and to otherwise provide for the construction and
development of first class quality improvements on such property.

          Therefore, in consideration of the premises and of the mutual benefits
and duties herein contained, and for the overall development of the property
subjected to this Declaration as a consistent and unified whole, Declarant
hereby declares for itself and its successors and assigns, that the parcels of
real property hereinafter described shall be held, sold and conveyed subject to
the following covenants, reservations, easements, conditions and restrictions,
all of which are for the purpose of protecting the value and desirability of,
and which shall run with, the real estate shown in Exhibit A, and which shall be
binding on all parties having any right, title, or interest

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

<PAGE>

therein, along with their heirs, successors, and assigns, and which shall inure
to the benefit of each owner thereof.

                                   ARTICLE I

                            Definition and Purpose
                            ----------------------

Section 1.  Definitions.
---------   -----------

(a)  "Architectural Committee" shall mean the Committee established pursuant to
     Article VII:, Section 10 of this Declaration.

(b)  "Association" shall mean and refer to the [*] Owners Association, Inc., its
     successors and assigns, a corporation formed or to be formed by Declarant.

(c)  "Common Property" shall mean and refer to all real property (if any) that
     is owned, now or in the future, by the Association for the common use and
     enjoyment of all the owners.

(d)  "Common Use and Access Easement" shall mean an easement in favor of the
     Association and its employees, agents or contractors (but not in favor of
     any individual owner) to install, maintain, repair and replace (i) any and
     all utility lines (other than utility lines serving any individual
     building, which are the responsibility of the Owner of such building),
     landscaping and vegetation and any roadway signage or park entry signage
     (other than any sign erected by an Owner referring to an individual site
     ("site entry signage"), which is the responsibility of the Owner of such
     site) within any Lot for a distance of fifty (50) feet from the edge of
     public rights of way within or adjacent to the Properties (such fifty (50)
     foot easement hereinafter also referred to as the Street Landscape
     Basement"), as shown on the record plat for each Lot, and ten (10) feet
     into each lot from the side and rear lot lines; and (ii) all entrances to
     [*], medians, streets and traffic signs and signals whether or not
     dedicated to a governmental authority; and (iii) all flood plain areas,
     drainage facilities and management ponds (whether within or outside a Lot)
     which serve [*].

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                       2
<PAGE>

(e)  "Declarant" shall mean and refer to Beau Meade Associates, a Maryland
     general partnership, the owner of record of the property shown on Exhibit
     A.

(f)  "Guidelines" shall mean and refer to the architectural and landscaping
     guidelines prepared by the Declarant and the Architectural Committee, and
     made available upon request to prospective purchasers, users and others, to
     implement the overall design scheme for the Property and to provide
     illustration of and guidance in the architecture, design details and
     landscaping features recommended by or acceptable to the Architectural
     Committee.  Declarant and the Architectural Committee shall have the right
     to modify, amend or update the Guidelines from time to time, on a
     prospective basis.  The Guidelines are intended to supplement this
     Declaration; however, in the event of any inconsistency between this
     Declaration and the Guidelines, the terms of this Declaration shall govern
     and control.

(g)  "Improvements" shall mean any and all structures, improvements, or
     betterments made or placed upon the properties or any portion thereof,
     including but not limited to any and all buildings, roofed structures,
     parking areas, loading docks or loading areas, fences, walls, hedges, mass
     plantings, poles, lighting fixtures, communications equipment, driveways,
     ponds, lanes, swimming pools, tennis courts, signs, picnic facilities, or
     any other improvements placed or built on the Properties by any person.

(h)  "Lot" shall mean and refer to any lot, parcel or tract of land subdivided
     out of the Properties in accordance with Loudoun County subdivision
     regulations.

(i)  "Member" or "Members" shall mean and refer to those persons or entitles
     entitled to membership in the Association as set forth In Article IV.  All
     Members, and the Lots which they own, shall be subject to and shall comply
     with the Articles of Incorporation and the Bylaws of the Association and
     any rules and regulations validly promulgated by the Association.

(j)  "Owner" or "Owners" shall mean and refer to the record owner, whether one
     or more persons or entitles, of the fee simple title to any Lot which is a
     part of the Properties,

                                       3
<PAGE>

     except those having such interest merely as security for the repayment of
     indebtedness or the performance of an obligation.

(k)  "Properties" or "Property" shall mean and refer to the real property shown
     on Exhibit A, along with any additional real property hereafter subjected
     to this Declaration.

                                  ARTICLE II

                                  Properties
                                  ----------

Section 1.  Description.  The real property made subject to this Declaration is
--------    -----------
shown on the plat marked as Exhibit A, which is attached hereto and made a part
hereof as if set forth in full in this Article II, Section 1.  The Declarant
reserves the right to subject additional property to the operation and effect of
this Declaration by recording an instrument to such effect (which instrument
shall specifically describe such additional property) in the office of the Clerk
of the Circuit Court for Loudoun County, Virginia.

                                  ARTICLE III

                Common Property/Common Use and Access Easement
                ----------------------------------------------

Section 1.  Title.  The Common Property shall be that property which is
---------   -----
specifically identified and shown as Common Property on the Declarant's record
plat of the Property, as approved by Loudoun County, Virginia, or which is
subsequently declared by Declarant to be Common Property and deeded by Declarant
to the Association.  The Common Property shall also include any subdivided land
contributed to the Association by an Owner.

Section 2.  Owner's Rights.  Every Owner shall have a right and easement of
--------    --------------
enjoyment in and to the Common Property which shall be appurtenant to and shall
pass with the title to every Lot subject to this Declaration and the bylaws,
rules and regulations adopted from time to time by the Association.

Section 3.  Common Use and Access Easement.  The Association and its employees,
---------   ------------------------------
agents and contractors (but not any individual owner in his or its individual
capacity as Owner) shall have a nonexclusive easement extending (i) fifty (50)
feet into each Lot from the edge of any public right of way within or adjacent
to the Properties (i.e., the Street Landscape Easement), as

                                       4
<PAGE>

shown on the record plat for each Lot, and (ii) ten (10) feet into each Lot from
the side and rear lot lines, for ingress, egress, and access to install,
maintain, repair, and replace any and all utility lines, landscaping and
vegetation and any roadway signage or park entrance signage within any such
areas. Any and all utility lines (other than utility lines seeing any individual
building), landscaping, vegetation, and signage so installed by the Association
shall comply with the requirements of this Declaration and the Exhibits hereto.
Notwithstanding the foregoing, it shall be the responsibility Of the Owner of
each Lot, concurrently with the construction of the initial Improvements on such
Lot, to install or cause to be installed the initial landscaping vegetation and
sprinkler system, and utility lines as necessary on the portion of such Owner's
Lot subject to the Common Use and Access Easement (except along Panorama Parkway
where such installations shall be provided by Declarant). The Association and
its employees, agents and contractors (but not any individual Owner in his or
its individual capacity as Owner) shall also have a nonexclusive easement to
enter upon any Lot to the extent necessary for the installation, maintenance,
repair and replacement of (i) the entrances to [*] and any medians, streets and
traffic signs and signals whether or not dedicated to a governmental authority,
and (ii) all flood plain areas, drainage facilities, and retention ponds
(whether within or outside a Lot) which serve [*] and are not dedicated to a
governmental authority. In no event, however, shall the Association have the
right to construct and install a storm water retention pond on the property of
any owner without the written consent of such owner.

                                  ARTICLE IV

                                  Membership
                                  ----------

Section 1.  Members.  Every person or entity who is an owner of any Lot which is
---------   -------
included in the Property shall be a Member of the Association and shall be
entitled to one vote for each acre (or fraction thereof In excess of 1/2 acre)
owned by such Owner in the Property.  If any Lot is leased for a term of 25
years or more (not including extensions or renewal options) the voting privilege
shall accrue to the lessee rather than the owner of fee simple title during the
term of the lease.  Every Member shall be bound by the Articles of Incorporation
and Bylaws of the Association.

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                       5
<PAGE>

Section 2.  Reservation of Declarant's Rights.  Notwithstanding anything to the
---------   ---------------------------------
contrary contained herein, Declarant shall have the right to assume the duty to
perform all of the functions of the Association and to refrain from establishing
the Association until the earlier to occur of (i) the sale by Declarant of the
last Lot in the Property owned by Declarant or (ii) ten (10) years from the date
of recordation of this Declaration in the land records of Loudoun County,
Virginia.  In the alternative, Declarant shall have the right to establish the
Association at any earlier date, whereupon the control of the Association shall
be determined by voting in accordance with the same procedure used for
amendments described in Article V, Section 1.

                                   ARTICLE V

                                    Voting
                                    ------

Section 1.  Amendments.
---------   ----------

(a)  This Declaration or any provision hereof, or any covenant, condition or
     restriction contained herein, may be terminated, extended, modified or
     otherwise amended, as to the whole of the subject Property or any portion
     thereof, with the written consent of Owners having fifty percent (50%) of
     the total number of votes in the Association; provided, however, that so
     long as Declarant owns a Lot or for a period of ten (10) years from the
     effective date hereof, whichever period is shorter, no such termination,
     extension, modification or other amendment shall be effective without the
     written approval of Declarant, which approval shall not be unreasonably
     withheld.

(b)  No such termination, extension, modification or other amendment to this
     Declaration that abrogates or limits the rights of any lender holding a
     mortgage or deed of trust or equivalent financing instrument encumbering a
     Lot as security for a loan may be made without the consent of all lenders
     who have provided the Association with notice of such mortgage or deed of
     trust and an address to which notices or requests for consent may be sent.

(c)  No such termination, extension, modification or other amendment shall be
     effective until a proper instrument in writing has been executed,
     acknowledged and recorded.

                                       6
<PAGE>

Section 2.  Special Assessments.  Special assessments relating to the Common
--------    -------------------
Property and the area of the Common Use and Access Easement may be made upon
approval by the Owners in accordance with the procedure described in Section
l(a) of this Article.

                                  ARTICLE VI

                                  Assessments
                                  -----------

Section 1.  Creation of Lien and Personal Obligation of Owner.  Each Owner of
---------   -------------------------------------------------
any Lot shall, by acceptance of a deed (or lease over twenty-five (25) years)
therefor, whether or not it shall be so expressed in any such deed, lease, or
other conveyance, be deemed to covenant and agree to all the terms and
provisions of this Declaration and any duly authorized amendment hereto, and
promises to pay to the Association both annual assessments and charges and duly
authorized special assessments, together with such interest thereon and costs of
collection therefore as are hereinafter provided, all of which shall be a charge
and continuing lien upon the Lot against which such assessment is made as of the
effective date of each assessment.  Any such lien shall, however, be subordinate
to the lien, operation and effect of any mortgage or deed of trust or equivalent
financing instrument encumbering such Lot or Lots and securing the repayment of
indebtedness and no lender shall be responsible for the repayment or discharge
of such lien.  Each such assessment, together with such interest thereon and
costs of collection therefore as are hereinafter provided, shall also be the
personal obligation of the person or entity who was the Owner of such Lot at the
time when the assessment fell due.  In the case of co-ownership of a Lot, all of
such co-owners shall be jointly and severally liable for the entire amount of
the assessment.  In no event, however, shall any lender holding an interest in
any Lot as security for the repayment of indebtedness (or a transferee from such
lender or a purchaser at a foreclosure sale) be liable for any of such
assessments, interests or collection charges unless such lender (or a transferee
from such lender or a purchaser at a foreclosure sale) acquires title to or
physical possession of such Lot, and in such event the lender's (or transferee
or purchaser's) responsibility for charges and assessments shall commence only
as of the date the lender (or transferee or purchaser) acquires title to or
physical possession of such Lot, and shall only apply to assessments becoming
due after the date on which such lender, transferee or purchaser acquires title
to or physical possession of such Lot.

                                       7
<PAGE>

Section 2.  Purpose of Annual Assessments.  The annual assessments levied by the
---------   -----------------------------
Association shall be used exclusively for the operation, maintenance, and repair
of the Common Property and the areas covered by the Common Use and Access
Easement, including, but not limited to, (i) the payment of any taxes and
insurance on the Common Property (ii) the costs of landscaping, sign and fence
maintenance and repair; (iii) the payment of utility bills on common facilities
(including water for sprinkler systems); (iv) the maintenance, repair, and
replacement of the common elements located at the entrances of [*], of dedicated
streets and medians (including traffic signs and signals) not accepted by the
Virginia Department of Transportation ("VDOT"), or those not dedicated to a
governmental authority, and of the flood plain areas, drainage facilities, and
retention ponds serving [*]; (v) for the cost of labor, equipment, materials,
management and supervision of all of the foregoing; and (vi) organizational and
operational expenses of the Association relating to the foregoing. The regular
annual assessment will be adjusted according to increases in costs (including
taxes, insurance and utility bills) and competitive bids submitted by qualified
management and maintenance companies approved by the Association.

Section 3.  Special Assessments.  In addition to the annual assessments
---------   -------------------
hereinabove authorized, the Association may levy special assessments for the
purpose of defraying, in whole or part, the cost of any construction or
reconstruction, unexpected repair or replacement of the Common Property or the
areas covered by the Common Use and Access Easement, including the necessary
fixtures and personal property related thereto; provided, however, that any such
special assessment shall be approved as set forth in Article V.  Special
assessments shall be due and payable on the date(s) which are fixed by the
resolution authorizing such assessment.

Section 4.  Commencement.  Assessments shall commence on the date fixed by the
---------   ------------
Association.  Assessments on Lots that first become, subject to assessments
during a calendar year shall be prorated on a calendar year basis for the
remainder of such calendar year.

Section 5.  Due Date.  Unless otherwise provided herein, annual assessments
---------   --------
shall be determined by the Association by January 31 of each calendar year and
shall be due and payable in full on a prospective basis for the upcoming year
within 30 days after the date on which such assessments are billed to an Owner
by the Association.

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                       8
<PAGE>

Section 6.  Records of Assessments.  The Association shall cause to be
---------   ----------------------
maintained in the office of the Association a record of all Lots and assessments
applicable thereto which shall be open for inspection by any Owner or lender.
Written notice of each assessment shall be mailed to every Owner of the Lot
subject to assessment, provided that such Owner shall have provided the
Association with an address to which such notice is to be mailed.  The
Association shall upon demand and payment of a reasonable charge furnish to any
Owner or lender a certificate in writing signed by an officer of the Association
and setting forth whether the assessments against the Owner's Lot have been
paid, and if so, the date through which such assessments have been paid, and if
not, the amount due and owing.  Such certificates shall be conclusive as
evidence for third parties as to the status of assessments against such Lot.

Section 7.  Effect of Non-Payment of Assessment.  If any annual assessment or
---------   -----------------------------------
special assessment is not paid on the date when due, then such assessment shall
be delinquent and shall accrue interest thereon from the due date at the highest
lawful rate deemed appropriate by the Board of the Association, not to exceed,
however, six percentage points over the annual yield rate on six month Treasury
Bills as of the first day of each month.  If such assessment is not paid within
thirty (30) days after the due date, then the Association may, after ten (10)
days written notice to the Owner and to any lender who has requested copies of
such notices, during which time the Owner or such lender may make such payment
without penalty, bring an action at law or in equity against the Owner
personally and/or to foreclose the lien against the Lot, and there shall be
added to the Amount of such assessments all reasonable attorneys' fees and costs
incurred by the Association in such actions, and in the event a judgment is
obtained, such judgment shall Include interest on the assessments as indicated
above.

                                  ARTICLE VII

                     Construction of Improvements and Uses
                     -------------------------------------

          Any and all Improvements constructed on any Lot, and any and all
alterations or changes to any such Improvements, shall require the prior written
approval of the Architectural Committee of the Association, and shall be
designed, constructed, used and operated In compliance with this Declaration and
the Guidelines.  Ordinary maintenance, repair, or replacement of portions of an
Improvement, if occasioned by normal wear and tear, and which

                                       9
<PAGE>

do not alter the exterior color and appearance of an Improvement, shall not
require Committee approval.

Section 1.  Permitted Uses and General Restrictions.
---------   ---------------------------------------

          A.  Permitted Uses.  Lots may be used for offices, research and
              --------------
development facilities, light assembly, and warehouses (other than "mini-
warehouses"), distribution facilities and such other compatible uses such as
servicing the products distributed as may be permitted from time to time under
the Zoning Ordinances of Loudoun County, Virginia (or such other governmental
authority having zoning jurisdiction over the Properties) except that in no
event shall any of the following uses be permitted: cemeteries (public or
private); commercial poultry, livestock and swine production, cattle feeder lots
or fur-bearing animal rearing or breeding farms; commercial animal kennels;
abattoirs; junk yards; bailing, storage or processing of scrap metal, glass,
paper or rags; storage or processing of wrecked or junked motor vehicles;
quarries; race tracks, raceways or dragstrips; sanitary land fills or garbage
disposal areas; trailer or mobile home parks; "mini-warehouses"; massage parlors
or similar business operations; or any other businesses which may produce or
emit substantial gases, smokes, odors or noises that are determined by the
Architectural Committee to be objectionable in a high quality, environmentally
controlled commercial development.

          Retail uses are allowed only if such use is a support facility for an
office use and whose primarily clientele is not the general public.
Notwithstanding the foregoing, a hotel use is a permissible use hereunder, if
and to the extent that a hotel use is alloyed by the Loudoun County Zoning
Ordinances, and such hotel may include retail uses incidental to the operation
of the hotel; provided, however, that said hotel shall be governed by this
Declaration.

          B.  General restrictions.  The Properties shall be continually
              --------------------
maintained by the Owners at all times, including during the process of
construction of improvements, in an attractively clean manner, free of trash,
rubbish and debris.  All uses and improvements shall conform with all federal,
state, and local building codes, zoning ordinances, bylaws and regulations, and
shall comply with current Loudoun County Zoning Ordinances and the regulation of
all governmental bodies with jurisdiction over the area of the Properties.

                                      10
<PAGE>

          C.  Resubdivision of Lots.  Any two or more Lots may be combined into
              ---------------------
a larger lot.  No Lot shall contain less than three (3) acres of land, unless
such Lot was shown on the subdivision plat originally recorded by Declarant as
containing less than three (3) acres.  Any resubdivision or consolidation of
such lots must conform with the Loudoun County Zoning and Subdivision
Ordinances.

          D.  Water, Sanitary, and Storm Sewer Easements.  Each Owner shall be
              ------------------------------------------
obligated upon request of another Owner to grant the requesting Owner without
cost (other than the cost of preparing and recording the easement, which shall
be borne by the requesting Owner) such easements as may be necessary to provide
the requesting Owner with adequate water, sanitary sewer, and storm water
management facilities (not including wet or dry storm water management ponds) to
serve the Improvements on the requesting Owner's property.  Any such easement
shall conclusively be deemed necessary if the requesting Owner is required by
Loudoun County, Virginia to provide such easement as a condition of obtaining
site plan approval or a building permit.  However, all Owners shall endeavor
during the design process to minimize the extent of easements for water,
sanitary sewer, and storm water management facilities on the property of other
Owners.

Section 2.  Lot Setbacks and Planting Requirements.
---------   --------------------------------------

          A.  Setback Requirements.  All Improvements shall comply with Loudoun
              --------------------
County, Virginia setback requirements.  In addition, no structure, building,
parking lot or area or any part thereof shall be located on any Lot in the
Street Landscape Easement.  The Building Setback Line shall be ten (10) feet
plus the height of the tallest building on a given Lot from a side interior
property line and the some distance from a rear property line.  Neither parking
areas nor driveways shall be located nearer than fifteen (15) feet from any
building or structure, or ten (10) feet from any interior property line.
Interior parking lot setback requirements between adjacent lots in the same
ownership (or between consenting owners who have coordinated the site design for
their parking areas) may be waived by the Architectural Committee if the
coordinated site design of the adjacent parcels is thus improved and if such
configuration would not unduly reduce the overall amount of landscaping on such
Lots and such configuration would not violate applicable Loudoun County
Ordinances.  No trees located in the Street Landscape Easement or

                                      11
<PAGE>

any Landscape Buffer (hereinafter defined) shall be removed except with prior
written approval by the Architectural Committee, which approval shall not be
unreasonably withheld or delayed.

     B.   Preservation of Landscape Buffers.  Any building or other structure
          ---------------------------------
above ground must conform to the Building Setback Line requirements described in
the preceding paragraph. In addition, the area extending ten (10) feet into a
Lot from the side and rear lot lines and the area extending fifteen (15) feet
into Lot from the sides and rear of any building on a Lot (except for service
courts and loading bays) shall be used solely as a landscaped planting strip
(hereinafter a "Landscape Buffer"), and it shall be the responsibility of each
Owner, at its sole expense, to landscape this area with lawn, trees, flowers and
shrubbery in conformance with the Guidelines and according to plans approved in
writing by the Architectural Committee. The Association will maintain the
planting strips and the cost of such maintenance will be borne by the Owners
through annual assessments.

     C.   Preservation of Street Landscape Easement.  The planting and
          -----------------------------------------
landscaping of the Street Landscape Easement are designed to provide a uniform
controlled environment which will set the aesthetic tone of [*]. Berms, trees,
ground cover, shrubs, lawn and other landscaping, shall be installed by each
Owner in connection with the construction of the Improvements on such Owner's
Lot, and shall conform to the Guidelines.

     D.   Landscape Buffers.  The planting and landscape design of Landscape
          -----------------
Buffers should be used to enhance and complement the design and appearance of
the building and, though subject to architectural review, is not prescribed by
this Declaration.

     E.   Landscaping Area and Maintenance Requirements.
          ---------------------------------------------

          1.   All Owners shall comply with and provide, as a minimum, the
               amount, type, and density of landscaping and erosion control
               required by Loudoun County ordinances as interpreted by Loudoun
               County from time to time.  All owners shall also comply with the
               landscaping requirements set forth in the Guidelines and in this
               Declaration.

          2.   Site Planting

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                      12
<PAGE>

               A consistent landscape plan shall be submitted for approval to
               the Architectural Committee.

          3.   Installation and Maintenance

               Each Owner shall install lawn, trees, flowers or shubbery in all
               landscaped areas and an underground sprinkler or watering system
               in the Street Landscape Easement.

               Maintenance of landscaping in Common Use and Access Easement
               areas shall be through a common assessment and maintenance
               program performed by the Association.  The maintenance of all
               other areas beyond the Street Landscape Easement shall be the
               responsibility of the Owner.

Section 3.  Building Design and Materials.
---------   -----------------------------

     A.   Building location shall conform to Loudoun County setback requirements
and the set-back requirements contained in this Declaration.

     B.   Building entry location is not specifically prescribed by this
Declaration, but shall be reviewed and approved by the Architectural Committee.

     C.   Building heights are controlled by Loudoun County Zoning Ordinances.

     D.   Truck parking and truck loading shall be permitted only in side and
rear yards which do not face the roadways.

     E.   Utilities Services and Appurtenances.  No articles, goods, materials,
          ------------------------------------
incinerators, storage tanks, refuse containers or like equipment shall be kept
in the open in front of any buildings or exposed to public view or view from any
neighboring properties. Water towers, storage tanks, transformers, pump houses,
processing equipment, stand fans, cooling towers, communication towers, vents,
stacks, skylights, mechanical rooms and any other structures or equipment
(whether freestanding or roofmounted) shall be architecturally compatible or
effectively shielded from public view by an architecturally approved method
organized in an aesthetically pleasing manner to provide a "roofscape" which
shall conform to the Guidelines

                                      13
<PAGE>

and shall be approved in writing by the Architectural Committee before
construction or erection of said structures or equipment. All on-site utility
services on any Lot or within the Common Property shall be located in accordance
with the Guidelines.

     F.   Building Materials and Finishes.  All buildings and improvements
          -------------------------------
constructed or erected upon the Properties shall conform to the Guidelines and
shall be approved by the Architectural Committee.  All buildings and
improvements constructed or erected upon the Properties shall also conform to
the minimum standards specified by the applicable governmental building codes in
effect at the time of such construction as well as to all other rules,
regulations, requirements, ordinances and laws of any local, state or federal
governmental unit(s) or authorities having jurisdiction thereof.

Section 4.  Site Entry Design.
---------   -----------------

     The site entry design shall conform to the Guidelines and shall be approved
by the Architectural Committee.

Section 5.  Parking Lot Design and Restrictions.
---------   -----------------------------------

     Off-street parking must be provided and maintained by the Owner of each Lot
in accordance with the Guidelines. The number of spaces shall conform to the
requirements imposed by the Zoning Ordinances of Loudoun County, Virginia and
the Guidelines. Onstreet parking or parking in the Street Landscape Easement
shall be prohibited. All parking must be screened from the roadways and adjacent
properties by berms and plantings.

Section 6.  Grading and Drainage Requirements.
---------   ---------------------------------

     A.   All flood plains located within the Property shall be preserved as
a natural landscape area not to be filled or modified in any way without prior
review of Loudoun County and State authorities and approval of the Architectural
Committee.  The planting and retention of hardwood trees in flood plains is
strongly encouraged.

     B.   Storm Drainage Systems.  The storm drainage system for any
          ----------------------
Improvements shall be consistent with the overall storm water management system
designed by the Declarant.  All Owners shall provide details (conforming to
Loudoun County detail requirements) of proposed

                                      14
<PAGE>

storm drainage systems to the Architectural Committee for approval. All such
drainage plans and facilities shall likewise comply with all rules, regulations
and requirements of the Loudoun County Technical Services Department and for
other governmental authority(ies) having jurisdiction thereof.

     Specific design for any storm water management system should follow the
following basic guidelines:

          1.   The course of proposed drainage channels should generally follow
               the drainage patterns of the existing topography.

          2.   During construction all surface runoff must be retained on site.

          3.   Erosion and Sediment control - During construction, erosion and
               sediment controls must be provided in accordance with Loudoun
               County regulations.

          4.   Lawn areas should utilize grass swales to collect and distribute
               surface runoff.  These should be designed to operate on a minimum
               of 10 year storm frequency.

          5.   Where grass channels are inadequate, naturalistic channels of
               rip-rap may be utilized.  Such channels should be heavily planted
               to resemble natural beds of small streams.

          6.   Roof drainage is to be channeled through downspouts located
               within the building and linked directly to an underground system
               or drainage channel.  No exterior gutters or downspouts will be
               permitted.

Section 7.  Road and Pathway Construction.
---------   -----------------------------

     A.   All public street construction shall conform to VDOT standards,
including curbs and gutters, asphalt paving and road beds.

                                      15
<PAGE>

     B.   All parking areas, loading areas and driveways are to be surfaced with
concrete, bituminous concrete, brick, or approved equal material. Curbs shall be
concrete. Asphalt curbs will not be permitted.

     C.   All site pathways, including jogging trails, shall be of materials
approved by the Architectural Committee.  Plazas and sidewalks adjacent to
buildings and parking areas may be of other paving surfaces integrated with the
building design, as approved by the Architectural Committee.

Section 8.  Lighting.
---------   --------

     All lighting shall conform to state and county regulations and to the
requirements set forth in the Guidelines, and shall be approved by the
Architectural Committee.

Section 9.  Signage.
---------   -------

     The size, shape, design and location of all signs shall conform to the
Guidelines and shall be shown on the plans submitted to the Architectural
Committee for approval. In no event shall the size, design, amount,
configuration or location of signage exceed or violate that permitted by the
Loudoun County Zoning Ordinance. There may be one temporary sign per lot for
persons offering the building for sale or lease. This sign may also include the
names of builders, architects, engineers and lenders involved in the
construction of the project. The temporary sign shall not exceed thirty-two (32)
square feet and shall be removed within thirty (30) days after completion of
sale or lease of the building.

Section 10.    Composition of Architectural Committee;
               --------------------------------------
               Submissions of Development Proposals
               ------------------------------------
               for Architectural Committee Approval.
               ------------------------------------

     The Architectural Committee shall consist of five (5) members appointed by
Declarant (and Declarant shall be empowered to appoint their successors should a
vacancy occur), and their names shall be maintained at Declarant's offices.  The
Architectural Committee shall keep minutes of its meetings and records of any
actions taken by consent in lieu of meeting, and such

                                      16
<PAGE>

minutes and records shall be open for inspection by any Owner in the offices of
the Association during regular business hours.

     Approval of each project shall be based on a general goal of producing a
high quality office and industrial park.  Before commencing the construction,
reconstruction, relocation or alteration of any Improvements, including but not
limited to any buildings, additions, enclosures, fences, loading docks, entrance
ways, exit ways, curb cuts, parking facilities, storage yards or any other
structures or permanent improvements on any Lot, the Owner shall make
submissions in four stages: 1) Preliminary Sketch; 2) Preliminary Plans; 3)
Final Construction Plans; 4) Construction Site Plan.

     All submissions shall include certain information including:

1.   Name and address of applicant and firm preparing the submission

2.   Graphic scale  - minimum 1"=50'for site plans
                    - minimum 1"=20' for buildings

3.   North arrow

4.   Date of preparation

5.   Revisions from previous submittals

6.   Stage of submission; i.e., preliminary sketch, preliminary plans, final
     construction plans, construction site plan

7.   Gross area of individual buildings

8.   Vicinity map

STEP 1 SUBMISSION (Preliminary Sketch)
--------------------------------------

9.   The height, bulk, massing and building footprint of all buildings and
     related improvements

2.   The layout of all parking areas, including auto capacity

                                      17
<PAGE>

3.   Building and parking setbacks

4.   The location and size of all access road, curb cuts and median breaks

5.   Landscaping, including site grading and rough topography

6.   Preliminary utility layout

7.   Proposed Gross Floor Area of Improvements and resulting Floor Area Ratio of
     Improvements to land area, determined in accordance with the Loudoun County
     Zoning Ordinances.

STEP 2 SUBMISSION (Preliminary Plans)
-------------------------------------

1.   Dimensioned site plan with location and size of all buildings, parking
     areas, service areas, and screening walls

2.   Schematic site grading and drainage plan

3.   Schematic utility plan

4.   Schematic floor plans

5.   Schematic building elevations

6.   Building sections

7.   Schematic landscaping plan

8.   Conceptual signage plan

9.   Conceptual lighting plan

STEP 3 SUBMISSION (Final Construction Plans)
--------------------------------------------

1.   Site plan

2.   Site grading and drainage plan

                                      18
<PAGE>

3.   Utility plan

4.   Floor plans

5.   Building elevations

6.   Building sections

7.   Landscaping and irrigation plan

8.   Lighting plan

9.   Signage plans

10.  Exterior materials samples

11.  Building perspective or model

STEP 4 SUBMISSION (Construction Site Plan)
------------------------------------------

1.   Trailer location

2.   Materials storage

3.   Parking area

4.   Equipment cleaning area

5.   Erosion and siltation control

6.   Security fencing

     The Owner is required to engage an architect registered in the State of
Virginia for the preparation of the project plans and specifications.  If the
Owner shows that its employees meet such requirement, such requirement can be
waived by the Architectural Committee.  The Owner is further required to engage
such an architect to provide construction progress inspection services.  This
requirement can be waived by the Architectural Committee as described in the
preceding sentence.

                                      19
<PAGE>

Section 11.  Architectural Committee Review Process.
----------   --------------------------------------

     Any matter requiring review and approval by the Architectural Committee
shall be submitted directly to the Committee at the following address:

                                  (if mailed)

                             Beau Meade Associates
                          c/o Intergate Company, Inc.
                        Washington Dulles International
                                P.O. Box 17533
                            Washington, D.C. 20041
                                  ATTN:  [*]
                        Architectural Review Committee

                                (if delivered)

                             Beau Meade Associates
                          c/o Intergate Company, Inc.
                              110 Underwood Lane
                              (Route 606 and 866)
                           Sterling, Virginia 22170
                                  ATTN:  [*]
                        Architectural Review Committee

Five (5) complete copies of all plans, specifications, and related data
constituting a formal submission shall be provided to the Architectural
Committee, together with a cover letter identifying the materials as a formal
submission and describing the submission stage.  The Architectural Committee
will review each formal submission made by the applicant and will provide a
written response within twenty-one (21) days after receipt of the formal
submission; provided, however, that the twenty-one (21), day time period shall
not begin until all of the materials constituting a formal submission (including
the cover letter) have been received by the Architectural Committee.  The
Architectural Committee may take one of three actions:

1.   Approval

2.   Approval with conditions and

3.   Disapproval-resubmit.

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                      20
<PAGE>

     In the event the Architectural Committee shall fail to approve,
conditionally approve or disapprove the formal submission in writing within
twenty-one (21) days after actual receipt of the formal submission by the
Architectural Committee, such approval shall be deemed to have been given and
the Owner shall be deemed to have complied with this Declaration.  The formal
submission shall be delivered to the Architectural Committee in person or by
certified mail at the address designated above or such other address as may be
designated from time to time by Declarant or the Association.  If the
Architectural Committee approves the plans, the actual construction in
accordance with the plans shall be the responsibility of the Owner; provided,
however, upon the completion of the Improvements, and prior to occupancy, the
Owner shall notify Declarant, who shall have ten (10) days thereafter in which
to have the Improvements inspected by the Architectural Committee to insure that
the Improvements were completed substantially in accordance with those plans
approved by the Architectural Committee prior to construction.  In the event
that the Architectural Committee shall fail to approve or disapprove in writing
the completed Improvements within ten (10) days after receipt of notice from the
Owner that the Improvements are completed, such approval shall be deemed to have
been given and this Declaration will be deemed to have been complied with.  In
the event an Owner has made substantial changes from the original plans approved
by the Architectural Committee and such changes were within the scope of the
original review of the Architectural Committee but not previously approved by
the Architectural Committee, the Owner shall make the necessary corrections to
the Improvements at such Owner's sole cost and expense, unless the Architectural
Committee determines that it is appropriate to approve such changes.

     Any action to approve or disapprove a submission to the Architectura1
Committee shall be made by the vote in person, by proxy, or by consent, of three
(3) out of the five (5) members of the Architectural Committee.  If less than
five (5) members (but not less than three (3) members) of the Architectural
Committee are present (either in, person, by proxy, or by written consents) then
approval or disapproval may be granted by a majority of those present.  The
Architectural Committee shall have regular meetings at such intervals as may be
determined by the Architectural Committee from time to time, but no less
frequently than quarterly.  Any special meeting of the Architectural Committee
shall be held on not less than five (5) days written notice, and the notice of
special meeting shall state the action required to be taken at such special
meeting and the Lot or Lots involved in such action.

                                      21
<PAGE>

     No permission or approval granted by Declarant or the Architectural
Committee with respect to construction pursuant to these restrictions shall
constitute or be construed as an approval by them of the structural stability,
safety, or design of any building, structure or other Improvement, and no
liability shall accrue to Declarant or the Architectural Committee in the event
that any such construction shall subsequently prove to be defective.  No
structure of a temporary nature shall be allowed on any Lot at any time except
that of an Owner's contractors and subcontractors during the period of
construction of Improvements.

     In addition to the approval of plans and other matters herein set forth,
the Architectural Committee shall have the right to waive minor violations and
allow minor variances where the same resulted unintentionally or without gross
carelessness on the part of any Owner and are not materially harmful to the
Properties.  If such a waiver is granted in writing, then thereafter such
matters so waived shall no longer be deemed a violation of these restrictions.

                                 ARTICLE VIII

                              General Provisions
                              ------------------

Section 1.  Duration.  These restrictions shall be appurtenant to and run with
---------   --------
the land comprising the Properties and shall be binding upon all Owners and
parties hereinafter having an interest in any of the Properties and all parties
claiming under them for a period of fifty (50) years from the date of the
recordation of this Declaration in the Office of the Clerk of the Circuit Court
for Loudoun County, Virginia.

Section 2.  Enforcement.  These restrictions may be enforced by Declarant, its
---------   -----------
successors and assigns or the Association by proceeding at law or in equity
against the person, firm or other entity violating or attempting to violate any
covenant or covenants, either to restrain the violation thereof or to recover
damages therefor together with reasonable attorneys' fees and court costs.
Further, in the event that the Association incurs expenses in performing any
work required by this Declaration to be performed by an Owner but which the
Owner failed, after notice, to perform, the Association shall have a lien on the
Lot or Lots owned by such Owner and on which such work was performed.  Such lien
may be enforced in the manner provided in Article VI, Section 7 for the
enforcement of assessments.  Any such lien shall, however, be subordinate to the
lien, operation, and effect of any mortgage or deed of trust encumbering such
Lot or Lots and

                                      22
<PAGE>

securing the repayment of indebtedness, and no lender shall be liable for the
repayment or discharge of any such lien. In the event the Association fails to
act to enforce any restriction herein, any Owner may enforce these restrictions
through judicial action against any other Owner, but no Owner shall have any
lien rights whatsoever as to any other Lot or Owner.

Section 3.  Partial Invalidity.  Any invalidation of any one or more of these
---------   ------------------
restrictions by judgment, court order, or statute or failure on the part of
Declarant or its successors or assigns to enforce any of said restrictions shall
in no way affect any of the other provisions hereof or be deemed as a waiver of
the right to enforce such restrictions any time after the violation thereof.

Section 4.  Abatement.  In the event that any Owner violates any of the terms or
---------   ---------
conditions of these restrictions and fails to cure the same within thirty (30)
days after written notice thereof then Declarant, or the Association, in
addition to the other rights and remedies provided for herein, shall have the
express right and privilege and license to enter upon any Lot to take any
reasonable action to cure such violation, and all reasonable costs thereof shall
be at the expense of the Owner of such Lot, and neither Declarant nor the
Association shall have any liability for any damage or injury to any person or
entity in connection with such entry, except for damage or injury resulting from
the gross negligence or willful misconduct of Declarant or the Association.

Section 5.  Exoneration of Declarant.  Each Owner of any Lot in the Properties
---------   ------------------------
or any other party having an interest in the Properties or any portion thereof
expressly agrees that:

     (a)    No duty or obligation is imposed upon Declarant to enforce or
            attempt to enforce any of the covenants or restrictions contained
            herein, nor shall Declarant be subject to any liability of any kind
            or nature whatsoever from any third party as a result of failing to
            enforce same, and

     (b)    Declarant's approval (or approval by the Architectural Committee) of
            any building plans, specifications, site or landscape plans or
            elevations or any other approvals or consents given by Declarant (or
            by the Architectural Committee) pursuant hereto or otherwise shall
            not be deemed a warranty, representation or covenant that any such
            buildings, improvements, landscaping or other action taken pursuant
            hereto or in reliance thereon is in compliance with any or all

                                      23
<PAGE>

            applicable laws, rules, requirements or regulations, the sole
            responsibility for all of same being upon the respective Owner; and

            Declarant and the Architectural Committee are expressly released and
            relieved of any and all liability in connection therewith.

Section 6.  Assignment.  Any and all of the rights, powers and reservations of
---------   ----------
Declarant herein contained may be assigned to any person, corporation or
association which will assume the duties of Declarant pertaining to the
particular rights, powers and reservations assigned, and upon any such person,
corporation or association evidencing its consent in writing to accept such
assignment and assure such duties he, she or it shall, to the extent of such
assignment, have the same rights and powers and be subject to the some
obligations and duties as are given to and assumed by Declarant herein.  If at
any time Declarant ceases to exist and has not made such an assignment, a
successor to Declarant may be appointed in the same manner as this Declaration
may be modified or amended under Article V.  Any assignment or appointment made
under this article shall be in recordable form and shall be recorded.

     In WITNESS WHEREOF, the Declarant has executed this Declaration of
Restrictive Covenants for [*] as of the 16 day of June, 1987.

                              BEAU MEADE ASSOCIATES,
                              a Maryland general partnership

                              By:  Beau Meade Land Investment
                                   Partnership, a Virginia general
                                   partnership, General Partner

                              By:  /s/ Jerome C. O'Connell
                                   -----------------------

                                 Jerome C. O'Connell, General Partner

_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                      24
<PAGE>

COUNTY OF LOUDOUN          )
                           )  ss:
COMMONWEALTH OF VIRGINIA   )

     I, Anne L. Kerr, a notary public in and for the aforesaid jurisdiction, do
certify that Jerome C. O'Connell, whose name, as general partner of Beau Meade
Land Investment Partnership, which is a general partner of Beau Meade
Associates, is signed to the foregoing instrument, bearing the date of June 16,
1987, has acknowledged the same before me in my County aforesaid.

     Given under my hand and official seal this 16th day of June, 1987.

                                        /s/ Anne L. Kerr
                                        ----------------------------------------
                                                    Notary Public

My commission expires:  MY COMMISSION EXPIRES OCTOBER 15, 1991
                        --------------------------------------
<PAGE>

                                   EXHIBIT A
                                   ---------

               [DESCRIPTION OF THE PROPERTY IN METES AND BOUNDS]
<PAGE>

                              FIRST AMENDMENT TO
                      DECLARATION OF PROTECTIVE COVENANTS
                                     [*]

          THIS FIRST AMENDMENT TO DECLARATION OF PROTECTIVE COVENANTS ("First
Amendment") made and entered into this 15th day of July, 1988, by BEAUMEADE
ASSOCIATES, a Maryland general partnership ("Declaration").

                                  WITNESSETH

          WHEREAS Declarant executed and recorded a certain Declaration of
Protective Covenants ("Declaration") for [*], dated June 16, 1987, recorded as
Instrument No. [*] at Deed Book [*], Page [*], in the office of the Clerk of the
Circuit Court for Loudoun County, Virginia; and

          WHEREAS Declarant wishes to amend the Declaration as more fully set
forth below.

          NOW, THEREFORE, in consideration of the foregoing, the Declaration is
amended by adding a new Article VI (Assessments), Section 8, as follows:

          Section 8.  Assessment Based on Acreage.  All assessments, whether
                      ---------------------------
          annual or special, shall be computed and allocated among the Lots on a
          per acre basis, so that each Owner of a Lot shall bear a percentage of
          the total annual or special assessments equal to a fraction, the
          numerator of which is the total acreage contained in such Lot and the
          denominator of which is the total acreage contained in all Lots in
          [*] and subject to this Declaration.

          Except as specifically amended by the foregoing, the Declaration
remains in full force and effect, unaltered in accordance with its terms.

          IN WITNESS WHEREOF, the Declaration has executed this First Amendment
to Declaration of Protective Covenants for [*] as of the 15th day of July,
1988.

                                   BEAUMEADE ASSOCIATES,
                                   a Maryland general partnership

                                   By:  BEAUMEADE LAND INVESTMENT
                                        PARTNERSHIP, a Virginia General
                                        Partnership, General Partner

                                   By:  /s/ Jerome C. O'Connell
                                        ----------------------------------------
                                        Jerome C. O'Connell,
                                        General Partner

                                       1
<PAGE>

COMMONWEALTH OF VIRGINIA     )
                             ) SS.
COUNTY OF FAIRFAX            )

          I, Linda H. Sheour, a notary public in and for the aforesaid
jurisdiction, do certify that Jerome C. O'Connell, whose name as general partner
of Beaumeade Land Investment Partnership, which is a general partner of
Beaumeade Associates is signed to the foregoing instrument, bearing the date of
July 15, 1988, has acknowledged the same before me in the jurisdiction
aforesaid.

          Given under my hand and official seal this 15th day of July 1988.

                                        /s/ Linda H. Sheour
                                        ----------------------------------------
                                        Notary Public

[SEAL]                                  My Commission expires:  4/27/9

                                     D-2-1
<PAGE>

                                   EXHIBIT E

                                    PARKING

          1.   AVAILABILITY; RENT.

          Landlord agrees that it will provide to Tenant sufficient space to
park two hundred thirty-five (235) automobiles, in the Park, or as otherwise
provided, at no additional cost to Tenant.  No specific parking spaces will be
allocated for use by Tenant.  Landlord reserves the right to institute either a
valet or self-parking system; provided, however, that if at any time during the
Term of the Lease Landlord provides to Tenant any additional spaces, Landlord
shall at all times have the right to reclaim such spaces upon thirty (30) days
notice to Tenant.

          2.   REGULATIONS; LIABILITY.

          Tenant and its employees, agents and invitees shall observe reasonable
safety precautions in the use of the parking' area get and shall at all limes
abide by all rules and regulations promulgated by Landlord and/or the parking
area operator governing use of the parking area.  Landlord does not assume any
responsibility for, and shall not be held liable for, any damage or loss to any
automobiles parked in the parking area or to any personal property located
therein, or for any injury sustained by any person in or about the parking area.

                                      E-1
<PAGE>

                                   EXHIBIT F

                            DESCRIPTION OF THE LAND

                         [Graphic Diagram of the Land]

                                      F-1
<PAGE>

                                   EXHIBIT G

                          SPECIAL TENANT REQUIREMENTS

          Landlord and Tenant hereby agree that, notwithstanding anything
contained in the Lease to the contrary, the provisions set forth below shall be
included as part of the Lease and, except as provided below, shall supercede any
inconsistent provisions of the Lease.  All references in the Lease and in this
Exhibit G to the Lease shall be construed to mean the Lease (and all exhibits
thereto), as amended and supplemented by this Exhibit G.  All terms not
otherwise defined in the Exhibit shall have the same meanings as set forth in
the Lease.

          1.   Use.

               1.1  Tenant's Use of Premises and Building and Land.  Subject to
Tenant's compliance with the requirements of Sections 8 and 9 of the Lease,
Tenant is permitted (a) to construct, maintain, operate and repair electronic,
transmitting and receiving equipment and supporting structures on the Premises,
including the roof of the Building, (b) to construct, maintain, operate and
repair an equipment room on the Premises, including the construction of an
upgraded fire suppression system which shall be a dry pipe, pre-action water
based system and Tenant reserves the right to install an environmentally
approved, gas, fire suppression system, (c) to install, upgrade, maintain,
operate and repair utility lines, transmission lines, and telecommunications
conduit and cabling (collectively, the "Conduits") in such locations on the
Building and Land as set forth in plans and specifications, which shall be
subject to Landlord's approval which shall not be unreasonably withheld,
conditioned or delayed, (d) reasonable ingress and egress over existing roadways
on the Land for Tenant's trucks and other vehicles, to maintain Tenant's
equipment and the Conduits (collectively, the "Tenant's Equipment").  The
Tenant's Equipment shall include, without limitation, the antenna, batteries,
uninterruptible power supply and such other equipment necessary thereto.  Tenant
shall have access to and use of the Premises, the Building, Land and the
Conduits, 24 hours per day, 365 days per year.

               1.2  Tenant's Use of Conduit Ducts.  Tenant shall have the right
to install, maintain, operate and repair the Conduits in any of Landlord's
conduit ducts located on the Building and Land, so long as Tenant's use of the
Conduits does not interfere with Landlord's use of Landlord's conduit ducts
located on the Building and the Land, if required for provisioning of any
utility service provider to the Building or telecommunications provider to the
Park (other than the Building).  Tenant will install separate conduit where
applicable.

          2.   Compliance with Law.  Nothing contained in this Exhibit G shall
in any way limit or negate Tenant's obligation to comply with laws in accordance
with the terms of the Lease.

          3.   Initial Installation and Testing.  Tenant shall have the rights,
at Tenant's sole cost and expense, at any time following the execution of the
Lease by Tenant in form mutually acceptable to Landlord and Tenant, to enter
upon the Building and Land and to carry out any test, inspections, pre-
installation and installation activities on the Building and Land as necessary
for the construction and installation of the Tenant's Equipment, including
without

                                      G-1
<PAGE>

limitation, engineering and environmental surveys, physical inspections, soil
test, inspections or pre-installation activities, Tenant shall, at Tenant's sole
cost and expense, repair any damages to the Building and the Land caused by such
inspections or pre-installation activities, including re-paving and re-
landscaping any affected areas of the Building and the Land. Any such entry onto
the Building and the Land prior to the Lease Commencement Date shall be on all
of the terms and provisions of the Lease, except for Tenant's obligation to pay
Rent; provided, however, that during the course of such entry and installation,
none of Tenant's employees, agents or contractors shall in any manner interfere
with or impede any of Landlord's employees, agents or contractors in the
performance of Landlord's Work or Additional Tenant Work.

          4.   Equipment Ownership: Surrender.  The Tenant's Equipment shall be
the property of and owned by Tenant throughout the Term, and shall in all event
be deemed trade fixtures, even if affixed to the Premises or the Building or the
Land.  On or before the Lease Expiration Date, Tenant shall remove the Tenant's
Equipment from the Premises, the Building and the Land and restore the Premises
as provided in Section 10 of the Lease.  Landlord agrees that the Tenant's
Equipment, Tenant's HVAC unit, and Tenant's Generator may be removed at any time
from the Premises, the Building and the Land by Tenant.

          5.   Emergency Power Generator.  Tenant shall have the right, at any
time during the Term, at Tenant's option and at Tenant's sole cost and expense:
(a) to install emergency power generators ("Tenant's Generator") on the Premises
in the location shown on Exhibit A.  In such location as is reasonably approved
by Landlord and the Beaumeade Association, to provide back-up emergency power
for the Tenant's Equipment and for Tenant's HVAC unit, and (b) to store fuel,
above ground, on the Premises or elsewhere as noted on Exhibit A, in such
locations as are reasonably approved by Landlord and the Beaumeade Association,
in such amounts as Tenant reasonably determines necessary for Tenant's
Generator.

          6.   No Interference:  Relocation

               6.1  No Interference.  Neither Landlord nor any of Landlord's
agents, employees, or contractors (collectively, the "Landlord Parties") shall
interfere in any way with the Tenant's Equipment or with Tenant's access to the
Tenant's Equipment and antennas, the Conduits, Tenant's HVAC unit, or Tenant's
Generator (the "Interference").  Landlord agrees that (except in an emergency,
when no notice shall be required) prior to Landlord's carrying out any
construction, maintenance or repair activities on the Land in the vicinity of
the antennas, the Conduits, Tenant's HVAC unit, or Tenant's Generator (if such
are not located within the Premises), Landlord shall endeavor to provide three
(3) days prior written notice or Landlord's of Landlord's Parties' intent to
carry out such construction, maintenance or repair work, including the location
in which such work will take place.  Tenant shall have the right to monitor and
inspect such work at Tenant's own risk, and at Tenant's sole cost and expense.
Landlord and Landlord Parties shall exercise all due care in carrying out such
work.  Landlord shall use reasonable efforts to immediately notify Tenant's
designated contact person by telephone or facsimile in the event of Landlord's
knowledge of fire, power failure, bomb threats, or other unplanned events which
could adversely impact Tenant's operations.

               6.2  Remedies.  Upon written notice from Tenant, stating with
specificity that Landlord or one or more of the Landlord Parties is creating an
interference in

                                      G-2
<PAGE>

violation of Section 6.1 of this Exhibit G, Landlord shall take immediately all
necessary measures at Landlord's sole cost and expense to eliminate the
interference, including hiring agents to work extended hours, until the
interference is eliminated.

               6.3  Relocation.  In no event shall Landlord relocate Tenant or
the Tenant's Equipment to other premises, or require Tenant to relocate the
Tenant's Equipment, for any length of time to any other location, either in or
on the Building or the Land or elsewhere.

          7.   Co-Location.  Landlord acknowledges that Tenant's business to be
conducted on the Premises requires the installation on the Premises of certain
communications equipment by certain licensees and customer of Tenant
(collectively, "Customers") in order for such Customers to interconnect with
Tenant's terminal facilities or to permit Tenant to manage or operate such
Customers' equipment, or otherwise as may be required pursuant to applicable
statutes and regulations.  Notwithstanding anything to the contrary contained in
the Lease, Landlord hereby consents in advance to any sublease, incense
agreement "co-location agreement" or similar agreement (collectively, "Customer
License") between Tenant and such a Customer for the limited purpose of
permitting such arrangements as described above.  The effectiveness of such
advance consent to a particular Customer License is conditioned upon such
Customer License being in writing and consistent with the provisions of the
Lease (although Tenant will only be required to provide Landlord a copy of the
executed Customer License if the Landlord requests it in writing).

          8.   Sound Control.  Tenant is responsible for taking the necessary
measures to reduce the sound transmission caused by the Tenant's Equipment.  In
addition, Tenant's Generator shall be installed in a weatherproof, walk-around
type, sound attenuating enclosure which shall limit the sound to no more than 85
dBA as measured at three (3) feet from any side, top or bottom, under all
operating conditions.

          9.   Confidentiality.  Landlord shall use reasonable efforts to keep
all Confidential Information of Tenant confidential.  For the purposes of the
Lease, "Confidential Information" includes any data or information pertaining to
Tenant or Tenant's business, regardless of medium, that is provided by Tenant to
Landlord, including Tenant's plans and specifications or electrical power
requirements, site plans, or copies of any such information, but excludes any
information (a) approved in writing by Tenant for release to third parties, (b)
that Landlord possesses independently of Tenant, (c) that Tenant places in the
public domain, or (d) that Landlord believes in good faith it is required to
disclose to any court, governmental agency or quasi-governmental agency after
having first notified Tenant of such good faith belief; provided, however, that
the provisions of this Paragraph 9 shall not be deemed to prohibit Tenant from
making public the provisions of this Lease with respect to tenant improvements,
rental rates, the Term or escalations for purposes of analysis of comparable
rents within any geographic area in which the Building is located, so long as
Tenant's name is not used in connection therewith; nor shall the provisions of
this Paragraph 9 be deemed to prohibit the furnishing of a copy of this Lease
and Tenant's then current financial statement to any purchaser or prospective
purchaser of the Park, the Building or the Land, or any combination thereof, or
any Mortgagee or Ground Lessor, prospective Mortgagee or prospective Ground
Lessor with respect to the Park, the Building or the Land, or any combination
thereof, or to any appraiser, accountant or other person having a bona fide role
in the evaluation of any actual or proposed sale, Mortgage or

                                      G-3
<PAGE>

Ground Lease, so long as, in each instance, the person receiving a copy of this
Lease and Tenant's then current financial statement executes a Nondisclosure
Agreement in a form which is substantially similar to that which is attached
hereto as Exhibit J and made a part hereof.

          10.  Indemnity.  Tenant acknowledges and agrees that Sections 14 and
15 of the Lease pertain to this Exhibit G.

                                      G-4
<PAGE>

                                   EXHIBIT H

DRAFT 10/31/99

                         EQUINIX, INC. AND SUBSIDIARY
                       (A Development Stage Enterprise)

                          Consolidated Balance Sheets

<TABLE>
<CAPTION>
                                                                                                    December 31,     September 30,
                                                                                                        1998              1999
                                                                                                -----------------   ----------------
                                                                                                         ---          (Unaudited)
                                                  Assets
<S>                                                                                                 <C>              <C>
Current assets:
   Cash and cash equivalents                                                                         $ 4,164,500         3,582,100
   Short-term investments                                                                              5,000,000        42,907,100
   Prepaids and other current assets                                                                     167,600         1,929,200
                                                                                                -----------------   ----------------
       Total Current assets                                                                            9,332,100        48,418,400

Property and equipment, net                                                                              482,000         2,716,400
Construction in progress                                                                                  30,700        19,862,200
Other assets                                                                                             156,400         1,440,200
                                                                                                -----------------   ----------------
       Total assets                                                                                   10,001,200        72,437,200
                                                                                                ================    ================
                                        Liabilities and Stockholder's Equity
Current liabilities:
   Accounts payable                                                                                  $    33,800           524,100
   Accrued construction costs                                                                            252,300         6,211,400
   Accrued expenses                                                                                       85,600           325,100
   Current portion of long-term obligations                                                                  ---         1,705,800
   Income taxes payable                                                                                   39,800               ---
                                                                                                -----------------   ----------------

       Total current liabilities                                                                         411,500         8,766,400

Long-term obligations                                                                                        ---         3,811,700
Other liabilities                                                                                            ---            45,000
                                                                                                -----------------   ----------------
       Total liabilities                                                                                 411,500        12,623,100
                                                                                                -----------------   ----------------
Commitments

Stockholder's equity:
Series A convertible preferred stock; $0.001 par value per share; 11,000,000 and
  14,000,000 shares authorized in 1998 and 1999, respectively; liquidation value                          10,400            12,400
  respectively and minimum redemption value of $10,465,000 and $12,445,000 in
  1998 and 1999,
Series B convertible preferred stock, $0.001 par value per share; none and
  16,000,000 shares authorized in 1998 and 1999, respectively; none and
  6,731,290 shares issued and outstanding in 1998 and 1999, respectively;                                    ---             6,700
  liquidation value and minimum redemption value of none and
  $53,850,320 in 1998 and 1999, respectively
Common stock $0.001 par value per share; 29,000,000 and 75,000,000 shares
  authorized on 1998 and 1999, respectively; 4,100,000 and 6,787,000 shares                                4,100             6,800
  issued in 1998 and 1999, respectively
Treasury stock                                                                                               ---           (10,000)
Additional paid-in capital                                                                            10,431,000        67,327,000
Deferred compensation                                                                                        ---           (67,400)
Other comprehensive income                                                                                   ---           147,300
Deficit accumulated during the development stage                                                        (855,800)       (7,608,700)
                                                                                                -----------------   ----------------
       Total stockholders' equity                                                                      9,589,700        59,814,100
                                                                                                -----------------   ----------------
       Total liabilities and stockholders' equity                                                     10,001,200        72,437,200
                                                                                                =================   ================
</TABLE>
                    See accompanying notes to consolidated financial statements.

                                      H-1
<PAGE>

DRAFT 10/31/99

                         EQUINIX, INC. AND SUBSIDIARY
                       (A Development Stage Enterprise)
                     Consolidated Statement of Operations

<TABLE>
<CAPTION>
                                                                      Period from             Nine months              Period from
                                                                     June 22, 1998               ended                June 22, 1998
                                                                    (inception) to           September 30,           (inception) to
                                                                      December 31,               1998                 September 30,
                                                                         1998                                             1999
                                                                    ---------------         ---------------          --------------
                                                                                              (Unaudited)              (Unaudited)
<S>                                                                  <C>                     <C>                      <C>
Selling, general, and administrative expenses                         $ 785,700                6,755,600               7,541,300

Stock-based compensation                                                    ---                  125,600                 125,600
                                                                    ---------------          --------------          --------------
Loss from operations                                                    785,700                6,881,200               7,666,900

Interest expense                                                            ---                  138,600                 138,600

Interest income                                                        (149,900)                (266,900)               (416,800)

Interest charge on beneficial conversion of convertible debt            220,000                      ---                 220,000
                                                                    ---------------           --------------         --------------
       Net loss                                                       $ 855,800                6,752,900               7,602,700
                                                                    ===============           ==============         ==============
</TABLE>

See accompanying notes to consolidated financial statements.

                                      H-2
<PAGE>

DRAFT 10/31/99

                          EQUINIX, INC. AND SUBSIDIARY

                        (A Development Stage Enterprise)

                      Consolidated Statement of Cash Flows

<TABLE>
<CAPTION>
                                                                            Period from           Nine months          Period from
                                                                           June 22, 1998            ended             June 22, 1998
                                                                           (inception) to        September 30,       (inception) to
                                                                            December 31,             1999             September 30,
                                                                                1998                                      1999
                                                                         -----------------     ----------------      ---------------
                                                                                                 (Unaudited)           (Unaudited)
<S>                                                                      <C>                   <C>                   <C>
Cash flows from operating activities:
 Net loss                                                                 $  (855,800)           (6,752,900)           (7,608,700)
 Adjustments to reconcile net loss to net cash provided by (used in)
 operating activities:
  Depreciation                                                                  4,200               248,100               252,300
  Interest charge on beneficial conversion of convertible debt                220,000                   ---               220,000
  Amortization of deferred stock-based compensation                               ---                67,400                67,400
  Amortization of deferred financing costs                                        ---                83,500                83,500
  Changes in operating assets and liabilities:
   Prepaids and other current assets                                         (167,600)           (1,761,600)           (1,929,200)
   Accrued construction costs                                                 252,300             5,959,100             6,211,400
   Accounts payable                                                            33,800               490,100               523,900
   Accrued expenses                                                            85,600               239,500               325,100
   Income taxes payable                                                        39,800               (39,800)                  ---

      Net cash provided by (used in) operating activities                    (387,700)           (1,466,600)           (1,854,300)

Cash flows from investing activities:
 Purchases of property and equipment                                         (486,200)           (2,482,500)           (2,968,700)
 Construction in progress                                                     (30,700)          (19,831,500)          (19,862,200)
 Other assets                                                                (156,400)           (1,283,700)           (1,440,100)
 Other liabilities                                                         (5,000,000)          (42,882,100)          (47,882,100)
 Maturities and sales of short-term investments                                   ---             5,122,200             5,122,200

      Net cash used in investing activities                                (5,673,300)          (61,312,600)          (65.985,900)

Cash flows from financing activities:
 Proceeds from debt and sale/leaseback arrangements                               ---             6,272,100             6,272,100
 Repayments of debt                                                               ---              (157,600)             (157,600)
 Gain on sale/leaseback transaction                                               ---               (77,700)              (77,700)
 Proceeds from issuance of common stock                                        10,000                   ---                10,000
 Proceeds from exercise of stock options                                          ---               288,700               288,700
 Proceeds from issuance of promissory notes                                   220,000                   ---               220,000
 Proceeds from issuance of convertible preferred stock                      9,995,500            55,871,300            65,866,800

      Net cash provided financing activities                               10,225,500            62,196,800            72,422,300

Net increase (decrease) in cash and cash equivalents                        4,164,500              (582,400)            3,582,100

Cash and cash equivalents at beginning of period                                  ---             4,164,500                   ---

Cash and cash equivalents at end of period                                  4,164,500             3,582,100             3,582,100
                                                                         =================     ================      ===============
 Supplemental cash flow information:

   Cash paid for taxes                                                            ---                67,500                67,500
                                                                         =================     ================      ===============
 Noncash financing and investing activities:
   Preferred stock warrants issued for financing commitments                      ---               600,700               600,700
   Deferred stock-based compensation on grants of stock options                   ---                67,400                67,400
   Conversion of notes payable to convertible preferred stock                 440,000                   ---               440,000
   Unrealized appreciation on investments                                         ---               147,300               147,300
                                                                         =================     ================      ===============
</TABLE>

See accompanying notes to consolidated financial statements.

                                      H-3
<PAGE>

                                   EXHIBIT I

                          FORM OF MEMORANDUM OF LEASE

          THIS MEMORANDUM OF LEASE ("Memorandum") is made effective as of the
_____ day of ___________, ______, by and between TRIZECHAHN CENTERS, INC. dba
TrizecHahn Beaumeade Corporate Management, a California corporation, its
successors and assigns, as landlord (collectively, "Landlord"), and EQUINIX,
INC., a Delaware corporation, its successors and assigns (collectively,
"Tenant").

          1.   Lease; Term.  Landlord and Tenant have entered into a Deed of
Lease (the "Lease") with respect to the premises described in Exhibit A
attached hereto and made a part hereof (the "Premises") in the building
located at [*], Ashburn, Virginia (the "Building"), which is located in the
business park known as [*] (the "Park"), for a term of ten (10) years after
the Lease Commencement Date (as such term is defined in the lease). Tenant has
three (3) Renewal Options (as defined in the Lease), each of which is for a
period of five (5) years.

          2.   Use of the Premises.  The Lease provides that Tenant shall use
the Premises only for the purposes permitted by Section 6 of the Lease.

          3.   Recordation.  Landlord and Tenant have agreed that, at the option
of either Landlord or Tenant, upon the execution of the Lease by each of them,
the original of this Memorandum may be recorded among the Land Records of
Loudoun County, Virginia and the party requesting recordation of this Memorandum
shall pay all of the costs of recordation thereof.

          4.   Lease Controls.  This Memorandum is intended for notice and
recording purposes only, and shall not supercede, diminish, add to or in any
manner change the terms of the Lease, it being understood that the terms of the
transaction shall be governed by the Lease.
_________________
*CONFIDENTIAL TREATMENT REQUESTED. CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

                                      I-1
<PAGE>

          IN WITNESS WHEREOF, Landlord and Tenant have executed this Memorandum
under seal as of the day and year first above written.

WITNESS:                                  LANDLORD:

                                          TRIZECHAHAN CENTERS, INC. dba
                                          TrizecHahn Beaumeade Corporate
                                          Management, a California corporation
By:___________________________            By:___________________________________
                                          Name:_________________________________
                                          Its:__________________________________

WITNESS/ATTEST:                           TENANT:

[Corporate Seal]                          EQUINIX, INC., a Delaware corporation
By:___________________________            By:___________________________________
Name:_________________________            Name:_________________________________
Its:__________________________            Its:__________________________________

COMMONWEALTH OF VIRGINIA

                                             )
                                             )ss:
COUNTY OF ____________________               )

          The foregoing instrument was acknowledged before me this _____ day of
_____________, ____ by _____________, in his/her capacity as ____________ of
TrizecHahn Center, Inc. dba TrizecHahn Beaumeade Corporation Management.

                                        ________________________________________
                                         Notary Public
[Notary Seal]

My commission expires:

                                      I-2
<PAGE>

COMMONWEALTH OF VIRGINIA                        )
                                                )ss:
COUNTY OF ____________________                  )

          The foregoing instrument was acknowledged before me this _____ day of
_____________, ____ by _____________, in his/her capacity as ____________ of
Equinix, Inc.

                                        ___________________________________

                                         Notary Public
[Notary Seal]

My commission expires:

                                      I-3
<PAGE>

                                   EXHIBIT J

                        FORM OF NONDISCLOSURE AGREEMENT

          In connection with a proposed business relationship, Equinix/SM/, Inc.
("Company") has disclosed or may disclose to you business information, technical
information and/or ideas ("Proprietary Information").

          In consideration of any disclosure and any negotiations concerning the
proposed business relationship, you agree as follows:

          1.   You will use your diligent, good faith efforts to hold in
confidence and not possess or use (except to evaluate within the U.S. the
proposed business relationship) or disclose any Proprietary Information except
information you can document (a) is in the public domain through no fault of
yours, (b) was properly known to you, without restriction, prior to disclosure
by Company, (c) was properly disclosed to you by another person without
restriction, or (d) was required to be disclosed by a court of competent
jurisdiction.  In any event you will not reverse engineer or attempt to derive
the composition or underlying information, structure or ideas of any Proprietary
Information.  The foregoing does not grant you a license in or to any of the
Proprietary Information.

          2.   If you decide not to proceed with the proposed business
relationship or if asked by Company, you will promptly return all Proprietary
Information and all copies, extracts and other objects or items in which it may
be contained or embodied.

          3.   You will promptly notify Company of any unauthorized release of
Proprietary Information of which you obtain actual knowledge.

          4.   You understand that this statement does not obligate Company to
disclose any information or negotiate or enter into any agreement or
relationship.

          5.   You acknowledge and agree that due to the unique nature of the
Proprietary Information, any breach of this agreement would cause irreparable
harm to Company for which damages are not an adequate remedy and that Company
shall therefore be entitled to equitable relief in addition to all other
remedies available at law, except for consequential or special damages.

          6.   The terms of this Agreement will remain in effect with respect to
any particular Proprietary Information until you can document that it falls into
one of the exceptions stated in Paragraph 1 above.

          7.   This Agreement is governed by the internal laws of the State of
Delaware and may be modified or waived only in writing.  If any provision is
found to be unenforceable, such provision will be limited or deleted to the
minimum extent necessary so that the remaining terms remain in full force and
effect.  The prevailing party in any dispute or legal action regarding the
subject matter of this Agreement shall be entitled to recover reasonable
attorney's fees and costs.

                                      J-1
<PAGE>

Acknowledged and agreed on October 28, 1999

Company:____________________________     Printed Name:__________________________

By:_________________________________     Title:_________________________________

                                      J-2<PAGE>

Net Office                         2450 Bayshore Parkway/Equinix, Inc. Page - 1

                                                                   EXHIBIT 10.17

                                LEASE AGREEMENT

     THIS LEASE AGREEMENT is made this 28th day of January, 2000, between ARE-
2425/2400/2450 GARCIA BAYSHORE LLC, a Delaware limited partnership ("Landlord"),
and EQUINIX, INC., a Delaware corporation ("Tenant").

Address:  2450 Bayshore Parkway, Mountain View, California

Premises: That portion of the Project, containing approximately 42,632 rentable
          square feet, as determined by Landlord, as shown on Exhibit A, and
          being 100% of the rentable square footage of the building located at
          2450 Bayshore Parkway, Mountain View, California ("Building").

Project:  The real property on which the building in which the Premises are
          located, together, with all improvements thereon and appurtenances
          thereto as described on Exhibit B.

Base Rent: $3.25/rentable square foot/month       Rentable Area of Premises:
                                                  42,632 sq.  ft

Rentable Area of Project: 98,964 sq.  ft.         Tenant's Share of Operating
                                                  Expenses:
                                                  100%

Building's Share of the Project:  43.08%          Security Deposit:  None.

Target Commencement Date: The earlier of the date  hereof or 2/1/2000

Rent Adjustment Percentage:   CPI Adjustment Percentage (as defined in
                              Section 4) but not less than 3% nor more
                              than 5% annually.

Base Term:     84 months from the first day of the first full month during which
               Base Rent is due and payable hereunder

Permitted Use: Office and related uses consistent with the character of the
               Building

Address for Rent Payment:                    Landlord's Notice Address:
135 N. Los Robles Avenue, Suite 250          135 N. Los Robles Avenue, Suite 250
Pasadena, CA 91101                           Pasadena, CA 91101
Attention: Accounts Receivable               Attention: General Counsel

Tenant's Notice Address:
901 Marshall Street
Redwood City, CA 94063
Attention: Mr. Philip Koen
<PAGE>

Net Office                         2450 Bayshore Parkway/Equinix, Inc. Page - 2

The following Exhibits and Addenda are attached hereto and incorporated herein
by this reference:

[X] EXHIBIT A - PREMISES DESCRIPTION    [X] EXHIBIT B - DESCRIPTION OF PROJECT
[X] EXHIBIT C - WORK LETTER             [X] EXHIBIT D - COMMENCEMENT DATE
[X] EXHIBIT E - RULES AND REGULATIONS   [X] EXHIBIT F - TENANT'S PERSONAL
PROPERTY
[X] EXHIBIT G - ESTOPPEL CERTIFICATE    [X] EXHIBIT H - NONDISTURBANCE AGREEMENT
<PAGE>

Net Office                         2450 Bayshore Parkway/Equinix, Inc. Page - 3

     1.   Lease of Premises.  Upon and subject to all of the terms and
conditions hereof, Landlord hereby leases the Premises to Tenant and Tenant
hereby leases the Premises from Landlord.  The portions of the Project which are
for the non-exclusive use of tenants of the Project are collectively referred to
herein as the "Common Areas." Landlord reserves the right to modify Common
Areas, provided that such modifications do not materially adversely affect
Tenant's use of the Premises for the Permitted Use.

     2.   Delivery; Acceptance of Premises; Commencement Date.  Landlord shall
use reasonable efforts to make the Premises available to Tenant for Tenant's
Work under the Work Letter within 2 days of full execution of this Lease and
Tenant's delivery of evidence of the insurance required hereby and by the Work
Letter ("Delivery" or "Deliver").  If Landlord fails to timely Deliver the
Premises, Landlord shall not be liable to Tenant for any loss or damage
resulting therefrom, and this Lease shall not be void or voidable except as
provided herein.  If Landlord does not Deliver the Premises within 60 days of
the Target Commencement Date for any reason other than Force Majeure Delays,
this Lease shall be voidable by Tenant by written notice to Landlord, and if so
voided: (a) so long as Tenant is not in default hereunder, the Security Deposit
shall be returned to Tenant, and (b) neither Landlord nor Tenant shall have any
further rights, duties or obligations under this Lease, except with respect to
provisions which expressly survive termination of this Lease.  As used herein,
the term "Force Majeure Delays" shall have the meaning set forth for such terms
in the Work Letter.  If Tenant does not elect to void this Lease within 5
business days of the lapse of such 60 day period, such right to void this Lease
shall be waived and this Lease shall remain in full force and effect.  Nothing
herein shall in any way limit Landlord's right to terminate this Lease pursuant
to Sections 18 or 19 hereof.

     The "Commencement Date" shall be the date Landlord Delivers the Premises to
Tenant Upon request of Landlord, Tenant shall execute and deliver a written
acknowledgment of the Commencement Date and the expiration date of the Term when
such are established in the form attached to this Lease as Exhibit D; provided,
however, Tenant's failure to execute and deliver such acknowledgment shall not
affect Landlord's rights hereunder.  The "Term" of this Lease shall be the Base
Term and any Extension Terms which Tenant may elect pursuant to Section 40
hereof.

     Except as set forth in the Work Letter and Section 7 regarding Landlord's
obligations with respect to the compliance of the Premises with Legal
Requirements as of the Commencement Date, if applicable: (i) Tenant shall accept
the Premises in their condition as of the Commencement Date, subject to all
applicable laws, ordinances, regulations, covenants and restrictions; (ii)
Landlord shall have no obligation for any defects in the Premises; and (iii)
Tenant's taking possession of the Premises shall be conclusive evidence that
Tenant accepts the Premises and that the Premises were in good condition at the
time possession was taken.  Any occupancy of the Premises by Tenant before the
Commencement Date shall be subject to all of the terms and conditions of this
Lease.

     Tenant agrees and acknowledges that neither Landlord nor any agent of
Landlord has made any representation or warranty with respect to the condition
of any or all of the Premises or the Project, and/or the suitability of the
Premises or the Project for the conduct of Tenant's business, and Tenant waives
any implied warranty that the Premises or the Project are suitable for the
Permitted Use.  This Lease constitutes the complete agreement of Landlord and
Tenant
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with respect to the subject matter hereof and supersedes any and all prior
representations, inducements, promises, agreements, understandings and
negotiations which are not contained herein. Landlord in executing this Lease
does so in reliance upon Tenant's representations, warranties, acknowledgments
and agreements contained herein.

     3.   Rent.

          (a)  Base Rent.  Tenant shall pay to Landlord in advance, without
demand, abatement, deduction or set-off, monthly installments of Base Rent on or
before the first day of each calendar month during the Term hereof, in lawful
money of the United States of America, at the office of Landlord for payment of
Rent set forth above, or to such other person or at such other place as Landlord
may from time designate in writing.  Payments of Base Rent for any fractional
calendar month shall be prorated and paid on the basis of a 30 day month.  The
obligation of Tenant to pay Base Rent and other sums to Landlord and the
obligations of Landlord under this Lease are independent obligations.  Tenant
shall have no right at any time to abate, reduce, or set-off any Rent due
hereunder except for any abatement as may be expressly provided in this Lease.
Notwithstanding anything herein to the contrary, so long as Tenant is not in
Default, Base Rent shall not be due or payable until May 1, 2000, provided,
however, that if the Premises are not available for Delivery (whether or not
this Lease has then been executed) on February 1, 2000, Base Rent shall not be
due until May 1, 2000, plus the number of days from February 1, 2000, until the
date the Premises are ready for Delivery.

          (b)  Additional Rent.  In addition to Base Rent, Tenant agrees to pay
to Landlord as additional rent ("Additional Rent"): (i) Tenant's Share of
"Operating Expenses," and (ii) any and all other amounts Tenant assumes or
agrees to pay under the provisions of this Lease, including, without limitation,
any and all other sums that may become due by reason of any default of Tenant or
failure to comply with the agreements, terms, covenants and conditions of this
Lease to be performed by Tenant, after any applicable notice and cure period.

     4.   Base Rent Adjustments.

          (a)  Additional Tenant Improvement Allowance.  For every dollar, or
portion thereof, of the Additional Tenant Improvement Allowance (as defined in
the Work Letter) disbursed by Landlord as provided in the Work Letter, Base Rent
shall increase by $0.018 per rentable square foot per month.

          (b)  CPI Adjustment Percentage.  Base Rent shall be increased on each
annual anniversary of the first day of the first full month during the Term of
this Lease by multiplying the Base Rent payable immediately before such
adjustment by the Rent Adjustment Percentage and adding the resulting amount to
the Base Rent payable immediately before such adjustment.  Base Rent, as so
adjusted, shall thereafter be due as provided herein.  Base Rent adjustments for
any fractional calendar month shall be prorated.  "CPI Adjustment Percentage"
means a fraction, stated as a percentage, the numerator of which shall be the
Index for the calendar month 3 months before the month in which the Base Rent
adjustment is to be made, and the denominator of which shall be the Index for
the calendar month 3 months before the last Base Rent adjustment or, if no prior
Base Rent adjustment has been made, 3 months before the first day of the first
full month during the Term of this Lease.  Landlord shall give
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Tenant written notice indicating the Base Rent, as adjusted pursuant to this
Section, and the method of computation, and Tenant shall pay to Landlord an
amount equal to any underpayment of Base Rent by Tenant within fifteen days of
Landlord's notice to Tenant. "Index" means the "Consumer Price Index-All Urban
Consumers-San Francisco Metropolitan Area" compiled by the U.S. Department of
Labor, Bureau of Labor Statistics, (1982-84 = 100). If a substantial change is
made in the Index, the revised Index shall be used, subject to such adjustments
as Landlord may reasonably deem appropriate in order to make the revised Index
comparable to the prior Index. If the Bureau of Labor Statistics ceases to
publish the Index, then the successor or most nearly comparable index, as
reasonably determined by Landlord, shall be used, subject to such adjustments as
Landlord may reasonably deem appropriate in order to make the new index
comparable to the Index.

     5.   Operating Expense Payments.  Landlord shall deliver to Tenant a
written estimate of Operating Expenses for each calendar year during the Term
(the "Annual Estimate"), which may be revised by Landlord from time to time
during such calendar year.  During each month of the Term, on the same date that
Base Rent is due, Tenant shall pay Landlord an amount equal to 1/12 of the
annual cost, as reasonably estimated by Landlord from time to time, of Tenant's
Share of Operating Expenses.  Payments for any fractional calendar month shall
be prorated.

     The term "Operating Expenses" means all costs and expenses of any kind or
description whatsoever incurred or accrued by Landlord with respect to the
Building (including the Building's Share of all costs and expenses of any kind
or description incurred or accrued by Landlord with respect to the Project which
are not specific to the Building or any other building located in the Project)
(including Taxes, reasonable reserves consistent with good business practice for
future repairs and replacements, capital repairs and improvements amortized over
the lesser of 7 years and the useful life of such capital items (provided that
any replacement roof shall be amortized over 10 years) and only the portion of
the costs so amortized during the Term of the Lease shall be included in
Operating Expenses, and the costs of Landlord's third party property manager or,
if there is no third party property manager, administration rent in the amount
of 3.0% of Base Rent), excluding only:

          (a)  the original design and construction costs of the Project and
renovation prior to the date of the Lease and costs of correcting defects in
such original construction or renovation;

          (b)  completing, fixturing, improving, renovating, painting,
redecorating or other work, which Landlord pays for or performs for specific
tenants within their premises and costs of correcting defects in such work;

          (c)  capital expenditures for expansion of the Project;

          (d)  interest, financing costs, principal and amortization of funds
borrowed by Landlord, whether secured or unsecured and all payments of base rent
(but not taxes or operating expenses) under any ground lease;
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          (e)  depreciation of the Project (except for capital improvements, the
cost of which are includable in Operating Expenses);

          (f)  advertising, legal and space planning expenses and leasing
commissions and other costs and expenses incurred in procuring tenants for the
Project, including any leasing office maintained in the Project;

          (g)  salaries, wages, benefits and other compensation paid to officers
and employees of Landlord who are not assigned in whole or in part to the
operation, management, maintenance or repair of the Project;

          (h)  costs of utilities (other than for Common Areas exterior to other
buildings in the Project;

          (i)  any expenses otherwise includable within Operating Expenses to
the extent actually reimbursed by persons other than tenants of the Project
under leases for space in the Project;

          (j)  legal and other expenses incurred in the negotiation or
enforcement of leases or in the enforcement of Landlord's title or interest in
the Project or any part thereof;

          (k)  costs relating to maintaining Landlord's existence, either as a
corporation, partnership, or other entity;

          (l)  costs (including attorneys' fees and costs of settlement,
judgments and payments in lieu thereof) arising from claims, disputes or
potential disputes pertaining to Landlord, but not the Project, or from
Landlord's failure to make any payment required to be made by Landlord hereunder
before delinquency;

          (m)  costs incurred by Landlord due to the violation by Landlord, its
employees, agents or contractors or any tenant of the terms and conditions of
any lease of space in the Project or any Legal Requirement;

          (n)  tax penalties incurred as a result of Landlord's negligence,
inability or unwillingness to make payment and/or to file any tax or
informational returns when due;

          (o)  overhead and profit increment paid to the Landlord or to
subsidiaries or affiliates of Landlord for goods and/or services in or to the
Project to the extent the same exceeds the costs of such goods and/or services
rendered by unaffiliated third parties on a competitive basis;

          (p)  costs arising from Landlord's charitable or political
contributions or fine art maintained at the Project;

          (q)  costs to be reimbursed by other tenants of the Project, whether
or not actually paid;
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          (r)  costs in connection with services (including electricity), items
or other benefits of a type which are not standard for the Project and which are
not available to Tenant without specific charges therefor, but which are
provided to another tenant or occupant of the Project, whether or not such other
tenant or occupant is specifically charged therefore by Landlord;

          (s)  costs incurred in the sale or refinancing of the Project;

          (t)  net income, franchise, capital stock, estate or inheritance
taxes;

          (u)  costs incurred by reason of the remediation or other
environmental response regarding any contamination of the Premises or the
Project or soils or groundwater thereunder, by Hazardous Materials, except to
the extent such contamination first originates during the Term as the result of
a breach by Tenant of its obligations under Section 30; and

          (v)  any deductible on a Landlord insurance policy to the extent
exceeding $25,000, or, in the case of a claim for earthquake damage, 5% of the
value of the Building.

     Within 90 days after the end of each calendar year (or such longer period
as may be reasonably required), Landlord shall furnish to Tenant a statement (an
"Annual Statement") showing in reasonable detail: (a) the total and Tenant's
Share of actual Operating Expenses for the previous calendar year, and (b) the
total of Tenant's payments in respect of Operating Expenses for such year.  If
Tenant's Share of actual Operating Expenses for such year exceeds Tenant's
payments of Operating Expenses for such year, the excess shall be due and
payable by Tenant as Rent within 30 days of Landlord's delivery of the Annual
Statement.  If Tenant's payments of Operating Expenses for such year exceed
Tenant's Share of actual Operating Expenses for such year Landlord shall, in its
sole and absolute discretion, either: (i) credit the excess amount to the next
succeeding installments of Operating Expenses due hereunder, or (ii) pay the
excess to Tenant within 30 days after delivery of such Annual Statement, except
that after expiration, or earlier termination of the Term, Landlord shall pay
the excess to Tenant within such 30 day period, after deducting all other
amounts due Landlord.

     The Annual Statement shall be final and binding upon Tenant unless Tenant,
within 30 days after Tenant's receipt thereof, shall contest any item therein by
giving written notice to Landlord, specifying each item contested and the reason
therefor.  If, during such 30 day period, Tenant reasonably and in good faith
questions or contests the correctness of Landlord's statement of Tenant's Share
of Operating Expenses, Landlord will provide Tenant with access to Landlord's
books and records relating to the operation of the Project and such information
as Landlord reasonably determines to be responsive to Tenant's questions.  If
after Tenant's review of such information, Landlord and Tenant cannot agree upon
the amount of Tenant's Share of Operating Expenses, then Tenant shall have the
right to have an independent public accounting firm selected from among the 6
largest in the United States, hired by Tenant (at Tenant's sole cost and
expense) and approved by Landlord (which approval shall not be unreasonably
withheld or delayed), audit and/or review Landlord's books and records relating
to the operation of the Project and such other information relating to the
operation of the Project for the year in question (the "Independent Review").
The results of any such Independent Review shall be binding on Landlord and
Tenant.  If the Independent Review shows that Tenant's pro rata share of the
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Operating Expenses actually paid by Tenant for the calendar year in question
exceeded Tenant's obligations for such calendar year, Landlord shall at
Landlord's option either (i) credit the excess amount to the next succeeding
installments of estimated Operating Expenses or (ii) pay the excess to Tenant
within 30 days after delivery of such statement, except that after expiration or
earlier termination of the Term, Landlord shall pay the excess to Tenant within
such 30 day period, after deducting all other amounts due Landlord.  If the
Independent Review shows that Tenant's payments of Tenant's Share of Operating
Expenses for such calendar year were less than Tenant's obligation for the
calendar year, Tenant shall pay the deficiency to the Landlord within 30 days
after delivery of such statement.  If the Independent Review shows that Tenant
has overpaid Tenant's pro rata share of Operating Expenses by more than 5% then
Landlord shall reimburse Tenant for all costs incurred by Tenant for the
Independent Review.  Operating Expenses for the calendar years in which Tenant's
obligation to share therein begins and ends shall be prorated.  Notwithstanding
anything set forth herein to the contrary, if the Project is not at least 95%
occupied on average during any year of the Term, Tenant's Share of Operating
Expenses for such year shall be computed as though the Project had been 95%
occupied on average during such year.

     "Tenant's Share" shall be the percentage set forth on the first page of
this Lease as Tenant's Share as reasonably adjusted by Landlord for changes in
the physical size of the Premises or the Project occurring thereafter.  Landlord
may equitably increase Tenant's Share for any item of expense or cost
reimbursable by Tenant that relates to a repair, replacement, or service that
benefits only the Premises or only a portion of the Project that includes the
Premises or that varies with occupancy or use.  Base Rent, Tenant's Share of
Operating Expenses and all other amounts payable by Tenant to Landlord hereunder
are collectively referred to herein as "Rent."

     6.   Security Deposit.  Intentionally omitted.

     7.   Use.  The Premises shall be used solely for the Permitted Use set
forth in the Basic Lease Provisions, in compliance with all laws, orders,
judgments, ordinances, regulations, codes, directives, permits, licenses,
covenants and restrictions now or hereafter applicable to the Premises, and the
use and occupancy thereof (collectively, "Legal Requirements").  Tenant shall,
upon 5 days' written notice from Landlord, discontinue any use of the Premises
which is declared by any governmental authority having jurisdiction to be a
violation of any Legal Requirement.  Tenant will not use or permit the Premises
to be used for any purpose or in any manner that would void Tenant's or
Landlord's insurance, increase the insurance risk, or cause the disallowance of
any sprinkler or other credits.  Tenant shall reimburse Landlord promptly upon
demand for any additional premium charged for any such insurance policy by
reason of Tenant's failure to comply with the provisions of this Section or
otherwise caused by Tenant's use and/or occupancy of the Premises.  Tenant will
use the Premises in a careful, safe and proper manner and will not commit waste,
overload the floor or structure of the Premises, subject the Premises to use
that would damage the Premises or obstruct or interfere with the rights of
Landlord or other tenants or occupants of the Project, including conducting or
giving notice of any auction, liquidation, or going out of business sale on the
Premises, or using or allowing the Premises to be used for any unlawful purpose.
Tenant shall cause any equipment or machinery to be installed in the Premises so
as to reasonably prevent sounds or vibrations therefrom from extending into
Common Areas, or other space in the Project.  Tenant shall not place any
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machinery or equipment weighing 500 pounds or more in or upon the Premises or
transport or move such items through the Common Areas of the Project or in the
Project elevators without the prior written consent of Landlord.  Except as may
be provided under the Work Letter, Tenant shall not, without the prior written
consent of Landlord, use the Premises in any manner which will require
ventilation, air exchange, heating, gas, steam, electricity or water beyond the
existing capacity of the Project as proportionately allocated to the Premises
based upon Tenant's Share as usually furnished for the Permitted Use.

     Landlord shall be responsible for the compliance of the Project with Legal
Requirements, including the Americans With Disabilities Act, 42 U.S.C. (S)
12101, et seq.  (together with regulations promulgated pursuant thereto, "ADA"),
as of the Commencement Date (in its then condition and before any work to be
undertaken by Tenant pursuant to the Work Letter).  Tenant, at its sole expense,
shall make any alterations or modifications, to the interior or the exterior of
the Premises or the Project, that are required by Legal Requirements (including,
without limitation, compliance of the Premises with the ADA) related to the
performance of Tenant's work under the Work Letter and/or Tenant's use or
occupancy of the Premises.  Notwithstanding any other provision herein to the
contrary, but subject to Landlord's obligations as of the Commencement Date of
the Lease, Tenant shall be responsible for any and all demands, claims,
liabilities, losses, costs, expenses, actions, causes of action, damages or
judgments, and all reasonable expenses incurred in investigating or resisting
the same (including, without limitation, reasonable attorneys' fees, charges and
disbursements and costs of suit) (collectively, "Claims") arising out of or in
connection with any failure of the Premises, or the Project to the extent
related to Tenant's use or occupancy of the Premises, to comply with any Legal
Requirement from and after the Commencement Date, and Tenant shall indemnify,
defend, hold and save Landlord harmless from and against any and all Claims
arising out of or in connection with any failure of the Premises, or the Project
to the extent related to Tenant's use or occupancy of the Premises, to comply
with any Legal Requirement from and after the Commencement Date.

     8.   Holding Over.  If, with Landlord's express written consent, Tenant
retains possession of the Premises after the termination of the Term, (i) unless
otherwise agreed in such written consent, such possession shall be subject to
immediate termination by Landlord at any time, (ii) all of the other terms and
provisions of this Lease (including, without limitation, the adjustment of Base
Rent pursuant to Section 4 hereof) shall remain in full force and effect
(excluding any expansion or renewal option or other similar right or option)
during such holdover period, (iii) Tenant shall continue to pay Base Rent in the
amount payable upon the date of the expiration or earlier termination of this
Lease or such other amount as Landlord may indicate, in Landlord's sole and
absolute discretion, in such written consent, and (iv) all other payments shall
continue under the terms of this Lease.  If Tenant remains in possession of the
Premises after the expiration or earlier termination of the Term without the
express written consent of Landlord, (A) Tenant shall become a tenant at
sufferance upon the terms of this Lease except that the monthly rental shall be
equal to 200% of the Rent in effect during the last 30 days of the Term, and (B)
Tenant shall be responsible for all damages suffered by Landlord resulting from
or occasioned by Tenant's holding over.  No holding over by Tenant, whether with
or without consent of Landlord, shall operate to extend this Lease except as
otherwise expressly provided, and this Section 8 shall not be construed as
consent for Tenant to retain possession of the Premises.  Acceptance by Landlord
of Rent after the expiration or earlier termination of the Term shall not result
in a renewal or reinstatement of this Lease.
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     9.   Taxes.  Landlord shall pay, as part of Operating Expenses, all taxes,
levies, assessments and governmental charges of any kind (collectively referred
to as "Taxes") imposed by any federal, state, regional, municipal, local or
other governmental authority or agency, including, without limitation, quasi-
public agencies (collectively, "Governmental Authority") during the Term,
including, without limitation all Taxes: (i) imposed on or measured by or based,
in whole or in part, on rent payable to Landlord under this Lease and/or from
the rental by Landlord of the Project or any portion thereof, or (ii) based on
the square footage, assessed value or other measure or evaluation of any kind of
the Premises or the Project, or (iii) assessed or imposed by or on the operation
or maintenance of any portion of the Premises or the Project, including parking,
or (iv) assessed or imposed by, or at the direction of, or resulting from
statutes or regulations, or interpretations thereof, promulgated by, any
Governmental Authority, or (v) imposed as a license or other fee on Landlord's
business of leasing space in the Project.  Landlord may contest by appropriate
legal proceedings the amount, validity, or application of any Taxes or liens
securing Taxes.  Taxes shall not include any net income taxes imposed on
Landlord unless such net income taxes are in substitution for any Taxes payable
hereunder.  If any such Tax is levied or assessed directly against Tenant, then
Tenant shall be responsible for and shall pay the same at such times and in such
manner as the taxing authority shall require.  Tenant shall pay, prior to
delinquency, any and all Taxes levied or assessed against any personal property
or trade fixtures placed by Tenant in the Premises, whether levied or assessed
against Landlord or Tenant.  If any Taxes on Tenant's personal property or trade
fixtures are levied against Landlord or Landlord's property, or if the assessed
valuation of the Project is increased by a value attributable to improvements in
or alterations to the Premises, whether owned by Landlord or Tenant and whether
or not affixed to the real property so as to become a part thereof, higher than
the base valuation on which Landlord from time-to-time allocates Taxes to all
tenants in the Project, Landlord shall have the right, but not the obligation,
to pay such Taxes.  Landlord's determination of any excess assessed valuation
shall be binding and conclusive, absent manifest error.  The amount of any such
payment by Landlord shall constitute Additional Rent due from Tenant to Landlord
immediately upon demand.

     10.  Parking.  Tenant shall have the right to park in common with other
tenants of the Project (in proportion to the rentable square feet in the
Premises and the aggregate rentable square feet in the Project) in those areas
designated for non-reserved parking subject in each case to Landlord's rules and
regulations.  The amount of such parking provided by Landlord to Tenant will be
in compliance with applicable codes as of the Commencement Date.  Landlord may
allocate parking spaces among Tenant and other tenants in the Project if
Landlord determines that such parking facilities are becoming crowded, or not in
compliance with Governmental Authority.  Landlord shall not be responsible for
enforcing Tenant's parking rights against any third parties, including other
tenants of the Project.

     11.  Utilities, Services.  Landlord shall pay, as Operating Expenses, for
all water, electricity, gas, telephone, sewer, and other utilities, refuse and
trash collection and landscaping and janitorial services (collectively,
"Utilities") used in the Common Areas of the Project, all maintenance charges
for Utilities, and any storm sewer charges or other similar charges for
Utilities imposed by any governmental entity or Utility provider, and any taxes,
penalties, surcharges or similar charges thereon.  Tenant shall pay directly to
the Utility provider, prior to delinquency, any separately metered Utilities and
services (including janitorial services) which may be furnished to Tenant or the
Premises during the Term.  Tenant shall pay, as part of
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Net Office                         2450 Bayshore Parkway/Equinix, Inc. - Page 11

Operating Expenses, its share of all charges for jointly metered Utilities based
upon consumption, as reasonably determined by Landlord. No interruption or
failure of Utilities, from any cause whatsoever other than Landlord's willful
misconduct, shall result in eviction or constructive eviction of Tenant,
termination of this Lease or the abatement of Rent. Tenant agrees to limit use
of water and sewer to normal restroom, lunchroom and office use.

     12.  Alterations and Tenant's Property. Any alterations, additions, or
improvements made to the Premises by or on behalf of Tenant, including
additional locks or bolts of any kind or nature upon any doors or windows in the
Premises, but excluding installation, removal or realignment of furniture
systems (other than removal of furniture systems owned or paid for by Landlord)
not involving any modifications to the structure or connections (other then by
ordinary plugs or jacks) to building systems (as hereinafter defined)
("Alterations") shall be subject to Landlord's prior written consent, which
shall not be unreasonably withheld, but which may be given or withheld in
Landlord's sole discretion if any such Alteration affects the structure or
building systems. Tenant may construct nonstructural Alterations in the Premises
without Landlord's prior approval if the aggregate cost of all such work in any
12 month period does not exceed $50,000 (a "Notice-Only Alteration"), provided
Tenant notifies Landlord in writing of such intended Notice Only Alteration, and
such notice shall be accompanied by plans, specifications, work contracts and
such other information concerning the nature and cost of the alteration as may
be reasonably requested by Landlord, which notice and accompanying materials
shall be delivered to Landlord not less than 15 business days in advance of any
proposed construction. If Landlord approves any Alterations requiring Landlord's
approval, Landlord may impose such conditions on Tenant in connection with the
commencement, performance and completion of such Alterations as Landlord may
deem appropriate in Landlord's reasonable discretion. Any request for approval
shall be in writing, delivered not less than 15 business days in advance of any
proposed construction, and accompanied by plans, specifications, bid proposals,
work contracts and such other information concerning the nature and cost of the
alterations as may be reasonably requested by Landlord, including the identities
and mailing addresses of all persons performing work or supplying materials.
Landlord's right to review plans and specifications and to monitor construction
shall be solely for its own benefit, and Landlord shall have no duty to ensure
that such plans and specifications or construction comply with applicable Legal
Requirements. Tenant shall cause, at its expense, all Alterations to comply with
insurance requirements and with Legal Requirements and shall implement at its
sole cost and expense any alteration or modification required by Legal
Requirements as a result of any Alterations. In connection with any Alteration
where the total cost of such Alteration equals or exceeds $50,000.00 in a 12
month period (excluding the initial improvements to be installed by Tenant in
preparing the Premises for its occupancy), Tenant shall pay to Landlord, as
Additional Rent, on demand an amount equal to 3% of all charges incurred by
Tenant or its contractors or agents to cover Landlord's overhead and expenses
for plan review, coordination, scheduling and supervision. Before Tenant begins
any Alteration, Landlord may post on and about the Premises notices of non-
responsibility pursuant to applicable law. Tenant shall reimburse Landlord for,
and indemnify and hold Landlord harmless from, any extra expense incurred by
Landlord by reason of faulty work done by Tenant or its contractors, delays
caused by such work, or inadequate cleanup.

     Tenant shall furnish security or make other arrangements satisfactory to
Landlord to assure payment for the completion of all Alteration work free and
clear of liens, and shall
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provide certificates of insurance for worker's compensation and other coverage
in amounts and from an insurance company reasonably satisfactory to Landlord
protecting Landlord against liability for personal injury or property damage
during construction. Upon completion of any Alterations, Tenant shall deliver to
Landlord: (i) sworn statements setting forth the names of all contractors and
subcontractors who did the work and final lien waivers from all such contractors
and subcontractors; and (ii) as built plans for any such Alteration.

     Other than (i) the items, if any, listed on Exhibit F attached hereto and,
(ii) any items reasonably agreed by Landlord in writing to be included on
Exhibit F in the future, and (iii) any trade fixtures, machinery, equipment and
other personal property not paid for out of the TI Fund (as defined in the Work
Letter) which may be removed without material damage to the Premises, which
damage shall be repaired by Tenant during the Term (the items in clauses (i)
through (iii) are collectively referred to herein as "Tenant's Property"), all
property of any kind paid for with the TI Fund, all Alterations, real property
fixtures, built-in machinery and equipment, built-in casework and cabinets and
other similar additions and improvements built into the Premises so as to become
an integral part of the Premises (collectively, "Installations") shall be and
shall remain the property of Landlord during the Term and following the
expiration or earlier termination of the Term.  Installations shall not be
removed by Tenant at any time during the Term and shall remain upon and be
surrendered with the Premises as a part thereof following the expiration or
earlier termination of this Lease; provided, however, that Landlord shall, at
the time its approval of Installations is requested or at the time it receives
notice of a Notice-Only Alteration, notify Tenant if it has elected to cause
Tenant to remove such Installation upon or prior to the expiration or earlier
termination of this Lease.  If Landlord so elects (other than with respect to
Tenant Improvements made under the Work Letter), Tenant shall remove any such
Installation upon the expiration or earlier termination of this Lease and
restore any damage caused by or occasioned as a result of such removal,
including, when removing any of Tenant's Property which was plumbed, wired or
otherwise connected to any of the building systems, capping off all such
connections behind the walls of the Premises and repairing any holes.  During
any such restoration period, Tenant shall pay Rent to Landlord as provided
herein as if said space were otherwise occupied by Tenant.

     13.  Landlord's Repairs. Landlord, as an Operating Expense, shall maintain
all of the structural, exterior, roof, parking and other Common Areas of the
Project as well as the plumbing, fire sprinkler and electrical building systems
serving the Premises and other portions of the Project ("Landlord Building
Systems"), in good repair, reasonable wear and tear and uninsured losses and
damages caused by Tenant, its agents, servants, employees, invitees and
contractors excluded. Losses and damages caused by Tenant, its agents, servants,
employees, invitees and contractors shall be repaired by Landlord, to the extent
not covered by insurance, at Tenant's sole cost and expense. Landlord reserves
the right to stop Utilities when necessary (i) by reason of accident or
emergency, or (ii) for planned repairs, alterations or improvements to common
area improvements, which are, in the judgment of Landlord, desirable or
necessary to be made, until said repairs, alterations or improvements shall have
been completed. Landlord shall have no responsibility or liability for failure
to supply Utilities during any such period of interruption; provided, however,
that Landlord shall give Tenant 24 hours advance notice of any planned stoppage
of Utilities for routine maintenance, repairs, alterations or improvements.
Tenant shall promptly give Landlord written notice of any repair required by
Landlord pursuant to this Section after which Landlord shall have a reasonable
opportunity to effect such repair.
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Landlord shall not be liable for any failure to make any repairs or to perform
any maintenance unless such failure shall persist for an unreasonable time after
Tenant's written notice of the need for such repairs or maintenance. Tenant
waives it rights under any state or local law to terminate this Lease or to make
such repairs at Landlord's expense and agrees that the parties' respective
rights with respect to such matters shall be solely as set forth herein. Repairs
required as the result of fire, earthquake, flood, vandalism, war, or similar
cause of damage or destruction shall be controlled by Section 18.

     14.  Tenant's Repairs. Subject to Section 13 hereof, Tenant, at its
expense, shall repair, replace and maintain in good condition all portions of
the Premises, including, without limitation, HVAC, elevators, entries, doors,
ceilings, interior windows, interior walls, and the interior side of demising
walls. Such repair and replacements may include capital expenditures and repairs
whose benefit may extend beyond the Term. Should Tenant fail to make any such
repair or replacement or fail to maintain the Premises, Landlord shall give
Tenant notice of such failure. If Tenant fails to commence cure of such default
within 30 days of Landlord's notice, and thereafter diligently prosecute such
cure to completion, Landlord may perform such work and shall be reimbursed by
Tenant within 10 days after written demand therefor; provided, however, that if
such default by Tenant creates or could create an emergency, Landlord may
immediately commence cure of such default and shall thereafter be entitled to
recover the costs of such cure from Tenant. Subject to Sections 17 and 18,
Tenant shall bear the full uninsured cost of any repair or replacement to any
part of the Project that results from damage caused by Tenant, its agents,
contractors, or invitees and any repair that benefits only the Premises.

     15.  Mechanic's Liens. Tenant shall discharge, by bond or otherwise, any
mechanic's lien filed against the Premises or against the Project for work
claimed to have been done for, or materials claimed to have been furnished to,
Tenant within 10 days after the filing thereof, at Tenant's sole cost and shall
otherwise keep the Premises and the Project free from any liens arising out of
work performed, materials furnished or obligations incurred by Tenant. Should
Tenant fail to discharge any lien described herein, Landlord shall have the
right, but not the obligation, to pay such claim or post a bond or otherwise
provide security to eliminate the lien as a claim against title to the Project
and the cost thereof shall be immediately due from Tenant as Additional Rent. If
Tenant shall lease or finance the acquisition of office equipment, furnishings,
or other personal property of a removable nature utilized by Tenant in the
operation of Tenant's business, Tenant warrants that any Uniform Commercial Code
Financing Statement executed by Tenant will upon its face or by exhibit thereto
indicate that such Financing Statement is applicable only to removable personal
property of Tenant located within the Premises. In no event shall the address of
the Project be furnished on the statement without qualifying language as to
applicability of the lien only to removable personal property, located in an
identified suite held by Tenant.

     16.  Indemnification. Tenant hereby indemnifies and agrees to defend, save
and hold Landlord harmless from and against any and all Claims for injury or
death to persons or damage to property occurring within or about the Premises,
arising directly or indirectly out of use or occupancy of the Premises or a
breach or default by Tenant in the performance of any of its obligations
hereunder, unless caused solely by the willful misconduct or gross negligence of
Landlord. Landlord shall not be liable to Tenant for, and Tenant assumes all
risk of damage to, personal property (including, without limitation, loss of
records kept within the Premises).
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Tenant further waives any and all Claims for injury to Tenant's business or loss
of income relating to any such damage or destruction of personal property
(including, without limitation, any loss of records). Landlord shall not be
liable for any damages arising from any act, omission or neglect of any tenant
in the Project or of any other third party.

     17.  Insurance.  Landlord shall maintain all insurance against any peril
generally included within the classification "Fire and Extended Coverage,"
sprinkler damage (if applicable), vandalism and malicious mischief covering the
full replacement cost of the Project.  Landlord shall further carry commercial
general liability insurance with a single loss limit of not less than $2,000,000
for death or bodily injury, or property damage with respect to the Project.
Landlord may, but is not obligated to, maintain such other insurance and
additional coverages as it may deem necessary, including, but not limited to,
flood, environmental hazard and earthquake, loss or failure of building
equipment, errors and omissions, rental loss during the period of repair or
rebuilding, workmen's compensation insurance and fidelity bonds for employees
employed to perform services and insurance for any improvements installed by
Tenant or which are in addition to the standard improvements customarily
furnished by Landlord without regard to whether or not such are made a part of
the Project.  All such insurance shall be included as part of the Operating
Expenses.  The Project may be included in a blanket policy (in which case the
cost of such insurance allocable to the Project will be determined by Landlord
based upon the insurer's cost calculations).

     Tenant, at its sole cost and expense, shall maintain during the Term: all
risk property insurance covering the full replacement cost of all property and
improvements installed or placed in the Premises by Tenant at Tenant's expense;
worker's compensation insurance with no less than the minimum limits required by
law; employer's liability insurance with such limits as required by law; and
commercial general liability insurance, with a minimum limit of not less than
$2,000,000 per occurrence for death or bodily injury and not less than
$1,000,000 for property damage with respect to the Premises.  The commercial
general liability insurance policies shall name Landlord, its officers,
directors, employees, managers, agents, invitees and contractors (collectively,
"Related Parties"), as additional insureds; insure on an occurrence and not a
claims-made basis; be issued by insurance companies which have a rating of not
less than policyholder rating of A- and financial category rating of at least
Class X in "Best's Insurance Guide"; shall not be cancelable unless 30 days
prior written notice shall have been given to Landlord from the insurer; contain
a hostile fire endorsement and a contractual liability endorsement; and provide
primary coverage to Landlord (any policy issued to Landlord providing duplicate
or similar coverage shall be deemed excess over Tenant's policies).  Such
policies or certificates thereof shall be delivered to Landlord by Tenant upon
commencement of the Term and upon each renewal of said insurance.  Tenant's
policy may be a "blanket policy" which specifically provides that the amount of
insurance shall not be prejudiced by other losses covered by the policy.  Tenant
shall, at least 10 days prior to the expiration of such policies, furnish
Landlord with renewals or binders.  Tenant agrees that if Tenant does not take
out and maintain such insurance, Landlord may (but shall not be required to)
procure said insurance on Tenant's behalf and at its cost to be paid as
Additional Rent.

     In each instance where insurance is to name Landlord as additional insured,
Tenant shall upon written request of Landlord also designate and furnish
certificates so evidencing Landlord as additional insured to: (i) any lender of
Landlord holding a security interest in the Project or
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any portion thereof, (ii) the landlord under any lease wherein Landlord is
tenant of the real property on which the Project is located, if the interest of
Landlord is or shall become that of a tenant under a ground lease rather than
that of a fee owner, and/or (iii) any management company retained by Landlord to
manage the Project.

     The property insurance obtained by Landlord and Tenant shall include a
waiver of subrogation by the insurers and all rights based upon an assignment
from its insured, against Landlord or Tenant, and their respective Related
Parties, in connection with any loss or damage thereby insured against. Neither
party nor its respective Related Parties shall be liable to the other for loss
or damage caused by any risk insured against under property insurance required
to be maintained hereunder, and each party waives any claims against the other
party, and its respective Related Parties for such loss or damage. The failure
of a party to insure its property shall not void this waiver. Landlord and its
respective Related Parties shall not be liable for, and Tenant hereby waives all
claims against such parties for, business interruption and losses occasioned
thereby sustained by Tenant or any person claiming through Tenant resulting from
any accident or occurrence in or upon the Premises or the Project from any cause
whatsoever. If the foregoing waivers shall contravene any law with respect to
exculpatory agreements, the liability of Landlord or Tenant shall be deemed not
released but shall be secondary to the other's insurer.

     Landlord may require insurance policy limits to be raised to conform with
requirements of Landlord's lender and/or to bring coverage limits to levels then
being required of new tenants within the Project.

     18.  Restoration. If at any time during the Term the Project or the
Premises are damaged by a fire or other insured casualty, Landlord shall notify
Tenant within 60 days after discovery of such damage as to the amount of time
Landlord reasonably estimates it will take to restore the Project or the
Premises, as applicable. If the restoration time is estimated to exceed 8
months, Landlord may, in such notice, elect to terminate this Lease as of the
date that is 75 days after the cat. of discovery of such damage or destruction.
Unless Landlord elects to terminate this Lease, Landlord shall, subject to
receipt of sufficient insurance proceeds (with any deductible to be treated as a
current Operating Expense), promptly restore the Premises (excluding the
improvements installed by Tenant or by Landlord and paid for by Tenant), subject
to delays arising from the collection of insurance proceeds, from Force Majeure
events or as needed to obtain any license, clearance or other authorization of
any kind required to enter into and restore the Premises issued by any
governmental or quasi-governmental agency having jurisdiction over the Premises,
including with respect to the use, storage, release or removal of Hazardous
Materials in, on or about the Premises (collectively referred to herein as "Use
Clearances"); provided, however, that if repair or restoration of the Premises
is not Substantially Complete as of the end of 8 months from the date of damage
or destruction, Landlord may, in its sole and absolute discretion, elect not to
proceed with such repair and restoration, or Tenant may, in its sole and
absolute discretion, elect to terminate this Lease by written notice delivered
within 5 business days of the expiration of such 8 month period, in which event
Landlord shall be relieved of its obligation to make such repairs or restoration
and this Lease shall terminate as of the date that is 75 days after the later
of: (i) discovery of such damage or destruction, or (ii) the date all required
Use Clearances are obtained.
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     Tenant, at its expense, shall promptly perform, subject to delays arising
from the collection of insurance proceeds, from Force Majeure events or to
obtain Use Clearances, all repairs or restoration not required to be done by
Landlord and shall promptly re-enter the Premises and commence doing business in
accordance with this Lease. Notwithstanding the foregoing, Landlord may
terminate this Lease upon 60 days prior written notice if the Premises are
damaged during the last 12 months of the Term and Landlord reasonably estimates
that it will take more than one month to repair such damage, or if insurance
proceeds are not available for such restoration.

     Rent shall be abated from the date all required Use Clearances are obtained
until the Premises are repaired and restored, in the proportion which the area
of the Premises, if any, which is not usable by Tenant in the manner in which
the damaged portion of the Premises were used by Tenant bears to the total area
of the Premises, unless Landlord provides Tenant with other space during the
period of repair that is reasonably suitable in Tenant's judgment for the
temporary conduct of Tenant's business.  Such abatement shall be the sole remedy
of Tenant, and except as provided herein, Tenant waives any right to terminate
the Lease by reason of damage or casualty loss.

     The provisions of this Lease, including this Section 18, constitute an
express agreement between Landlord and Tenant with respect to any and all damage
to, or destruction of, all or any part of the Premises, or any other portion of
the Project, and any statute or regulation which is now or may hereafter be in
effect, shall have no application to this Lease or any damage or destruction to
all or any part of the Premises or any other portion of the Project, the parties
hereto expressly agreeing this Section 18 sets forth their entire understanding
and agreement with respect to such matters.

     19.  Condemnation. If any part of the Premises or the Project is taken for
any public or quasi-public use under governmental law, ordinance, or regulation,
or by right of eminent domain, or by private purchase in lieu thereof (a
"Taking" or "Taken"), and the Taking would in Landlord's judgment either prevent
or materially interfere with Tenant's use of the Premises or materially
interfere with or impair Landlord's ownership or operation of the Project, then
upon written notice by Landlord this Lease shall terminate and Rent shall be
apportioned as of said date. If part of the Premises shall be Taken, and this
Lease is not terminated as provided above, Landlord shall promptly restore the
Premises and the Project as nearly as is commercially reasonable under the
circumstances to their condition prior to such partial taking and the Rent
payable hereunder during the unexpired Term shall be reduced to such extent as
may be fair and reasonable under the circumstances. Upon any such Taking,
Landlord shall be entitled to receive the entire price or award from any such
Taking without any payment to Tenant, and Tenant hereby assigns to Landlord
Tenant's interest, if any, in such award. Tenant shall have the right, to the
extent that same shall not diminish Landlord's award, to make a separate claim
against the condemning authority (but not Landlord) for such compensation as may
be separately awarded or recoverable by Tenant for moving expenses and damage to
Tenant's Trade Fixtures, if a separate award for such items is made to Tenant.
Tenant hereby waives any and all rights it might otherwise have pursuant to any
provision of state law to terminate this Lease upon a partial Taking of the
Premises or the Project.
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     20.  Events of Default. Each of the following events shall be a default
("Default") by Tenant under this Lease:

          (a)  Payment Defaults. Tenant shall fail to pay any installment of
Rent or any other payment hereunder when due; provided, however, that Landlord
will give Tenant notice and an opportunity to cure any failure to pay Rent
within 3 days of any such notice not more than once in any 12 month period and
Tenant agrees that such notice shall be in lieu of and not in addition to any
notice required by law.

          (b)  Insurance. Any insurance required to be maintained by Tenant
pursuant to this Lease shall be canceled or terminated or shall expire or shall
be reduced or materially changed, or Landlord shall receive a notice of
nonrenewal of any such insurance and Tenant shall fail to obtain replacement
insurance at least 10 days before the expiration of the current coverage.

          (c)  Abandonment.  Tenant shall abandon the Premises.

          (d)  Improper Transfer. Tenant shall assign, sublease or otherwise
transfer or attempt to transfer all or any portion of Tenant's interest in this
Lease or the Premises except as expressly permitted herein, or Tenant's interest
in this Lease shall be attached, executed upon, or otherwise judicially seized
and such action is not released within 90 days of the action.

          (e)  Liens. Tenant shall fail to discharge or otherwise obtain the
release of any lien placed upon the Premises in violation of this Lease within
10 days after Tenant has knowledge that any such lien has been filed against the
Premises.

          (f)  Insolvency Events. Tenant or any guarantor or surety of Tenant's
obligations hereunder shall: (A) make a general assignment for the benefit of
creditors; (B) commence any case, proceeding or other action seeking to have an
order for relief entered on its behalf as a debtor or to adjudicate it a
bankrupt or insolvent, or seeking reorganization, arrangement, adjustment,
liquidation, dissolution or composition of it or its debts or seeking
appointment of a receiver, trustee, custodian or other similar official for it
or for all or of any substantial part of its property (collectively a
"Proceeding for Relief"); (C) become the subject of any Proceeding for Relief
which is not dismissed within 90 days of its filing or entry; or (D) die or
suffer a legal disability (if Tenant, guarantor, or surety is an individual) or
be dissolved or otherwise fail to maintain its legal existence (if Tenant,
guarantor or surety is a corporation, partnership or other entity).

          (g)  Estoppel Certificate or Subordination Agreement. Tenant fails to
execute any document required from Tenant under Sections 23 or 27 within 5 days
after a second notice requesting such document.

          (h)  Other Defaults. Tenant shall fail to comply with any provision of
this Lease other than those specifically referred to in this Section 20, and
except as otherwise expressly provided herein, such failure shall continue for a
period of 10 days after written notice thereof from Landlord to Tenant.
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Any notice given under Sections 20 (g) or (h) hereof, shall: (i) specify the
alleged default, (ii) demand that Tenant cure such default, (iii) be in lieu of,
and not in addition to, or shall be deemed to be any notice required under any
provision of applicable law, and (iv) not be deemed a forfeiture or a
termination of this Lease unless Landlord elects otherwise in such notice;
provided that if the nature of Tenant's default pursuant to Section 20(h) is
such that it cannot be cured by the payment of money and reasonably requires
more than 10 days to cure, then Tenant shall not be deemed to be in default if
Tenant commences such cure within said 10 day period and thereafter diligently
prosecutes the same to completion; provided, however, that such cure shall be
completed no later than 120 days from the date of Landlord's notice.

     21.  Landlord's Remedies.

          (a)  Payment By Landlord; Interest. Upon a Default by Tenant
hereunder, Landlord may, without waiving or releasing any obligation of Tenant
hereunder, make such payment or perform such act. All sums so paid or incurred
by Landlord, together with interest thereon, from the date such sums were paid
or incurred, at the annual rate equal to 12% per annum or the highest rate
permitted by law (the "Default Rate"), whichever is less, shall be payable to
Landlord on demand as Additional Rent. Nothing herein shall be construed to
create or impose a duty on Landlord to mitigate any damages resulting from
Tenant's Default hereunder.

          (b)  Late Payment Rent. Late payment by Tenant to Landlord of Rent and
other sums due will cause Landlord to incur costs not contemplated by this
Lease, the exact amount of which will be extremely difficult and impracticable
to ascertain. Such costs include, but are not limited to, processing and
accounting charges and late charges which may be imposed on Landlord under any
Mortgage covering the Premises. Therefore, if any installment of Rent due from
Tenant is not received by Landlord within 5 days after the date such payment is
due, Tenant shall pay to Landlord an additional sum of 6% of the overdue Rent as
a late charge. The parties agree that this late charge represents a fair and
reasonable estimate of the costs Landlord will incur by reason of late payment
by Tenant. In addition to the late charge, Rent not paid when due shall bear
interest at the Default Rate from the 5th day after the date due until paid.

          (c)  Remedies. Upon the occurrence of a Default, Landlord, at its
option, without further notice or demand to Tenant, shall have in addition to
all other rights and remedies provided in this Lease, at law or in equity, the
option to pursue any one or more of the following remedies, each and all of
which shall be cumulative and nonexclusive, without any notice or demand
whatsoever .

               (i)  Terminate this Lease, or at Landlord's option, Tenant's
right to possession only, in which event Tenant shall immediately surrender the
Premises to Landlord, and if Tenant fails to do so, Landlord may, without
prejudice to any other remedy which it may have for possession or arrearages in
rent, enter upon and take possession of the Premises and expel or remove Tenant
and any other person who may be occupying the Premises or any part thereof,
without being liable for prosecution or any claim or damages therefor;

               (ii) Upon any termination of this Lease, whether pursuant to the
foregoing Section 21(c)(i) or otherwise, Landlord may recover from Tenant the
following:
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                      (A)  The worth at the time of award of any unpaid rent
which has been earned at the time of such termination; plus

                      (B)  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

                      (C)  The worth at the time of award of the amount by which
the unpaid rent for the balance of the Term after the time of award exceeds the
amount of such rental loss that Tenant proves could have been reasonably
avoided; plus

                      (D)  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, specifically including but not limited to, brokerage
commissions and advertising expenses incurred, expenses of remodeling the
Premises or any portion thereof for a new tenant, whether for the same or a
different use, and any special concessions made to obtain a new tenant; and

                      (E)  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 Section 21 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 Sections 21 (c)(ii) (A) and
(B), above, the "worth at the time of award" shall be computed by allowing
interest at the Default Rate.  As used in Section 21 (c)(ii)(C) 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 1%.

               (iii)  Landlord may continue this Lease in effect after Tenant's
Default and recover rent as it becomes due. Accordingly, if Landlord does not
elect to terminate this Lease following a Default by Tenant, Landlord may, from
time to time, without terminating this Lease, enforce all of its rights and
remedies hereunder, including the right to recover all Rent as it becomes due.

               (iv)   Whether or not Landlord elects to terminate this Lease
following a Default by Tenant, Landlord shall have the right to terminate any
and all subleases, licenses, concessions or other consensual arrangements for
possession entered into by Tenant and affecting the Premises or may, in
Landlord's sole discretion, succeed to Tenant's interest in such subleases,
licenses, concessions or arrangements. Upon Landlord's election to succeed to
Tenant's interest in any such subleases, licenses, concessions or arrangements,
Tenant shall, as of the date of notice by Landlord of such election, have no
further right to or interest in the rent or other consideration receivable
thereunder.

          (d)  Effect of Exercise. Exercise by Landlord of any remedies
hereunder or otherwise available shall not be deemed to be an acceptance of
surrender of the Premises and/or a termination of this Lease by Landlord, it
being understood that such surrender and/or termination can be effected only by
the express written agreement of Landlord and Tenant. Any law, usage, or custom
to the contrary notwithstanding, Landlord shall have the right at all times
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to enforce the provisions of this Lease in strict accordance with the terms
hereof; and the failure of Landlord at any time to enforce its rights under this
Lease strictly in accordance with same shall not be construed as having created
a custom in any way or manner contrary to the specific terms, provisions, and
covenants of this Lease or as having modified the same and shall not be deemed a
waiver of Landlord's right to enforce one or more of its rights in connection
with any subsequent default. A receipt by Landlord of Rent or other payment with
knowledge of the breach of any covenant hereof shall not be deemed a waiver of
such breach, and no waiver by Landlord of any provision of this Lease shall be
deemed to have been made unless expressed in writing and signed by Landlord. To
the greatest extent permitted by law, Tenant waives the service of notice of
Landlord's intention to re-enter, re-take or otherwise obtain possession of the
Premises as provided in any statute, or to institute legal proceedings to that
end, and also waives all right of redemption in case Tenant shall be
dispossessed by a judgment or by warrant of any court or judge. Any reletting of
the Premises or any portion thereof shall be on such terms and conditions as
Landlord in its sole discretion may determine. Landlord shall not be liable, nor
shall Tenant's obligations hereunder be diminished because of, Landlord's
failure to relet the Premises or collect rent due in respect of such reletting
or otherwise to mitigate any damages arising by reason of Tenant' Default.

     22.  Assignment and Subletting.

          (a)  General Prohibition. Without Landlord's prior written consent
subject to and on the conditions described in this Section 22, Tenant shall not,
directly or indirectly, voluntarily or by operation of law, assign this Lease or
sublease the Premises or any part thereof or mortgage, pledge, or hypothecate
its leasehold interest or grant any concession or license within the Premises
and any attempt to do any of the foregoing shall be void and of no effect. If
Tenant is a corporation, partnership or limited liability company, the shares or
other ownership interests of which are not actively traded upon a stock exchange
or in the over-the-counter market, a transfer or series of transfers whereby 50%
or more of the issued and outstanding shares or other ownership interests of
such corporation are, or voting control is, transferred (but excepting transfers
upon deaths of individual owners) from a person or persons or entity or entities
which were owners thereof at time of execution of this Lease to persons or
entities who were not owners of shares of the corporation, partnership or
limited liability company at time of execution of this Lease, shall be deemed an
assignment of this Lease requiring the consent of Landlord as provided in this
Section 22.

          (b)  Permitted Transfers. If Tenant desires to assign, sublease,
hypothecate or otherwise transfer this Lease or sublet the Premises other than
pursuant to a Permitted Assignment (as defined below), then at least 15 business
days, but not more than 45 business days, before the date Tenant desires the
assignment or sublease to be effective (the "Assignment Date"), Tenant shall
give Landlord a notice (the "Assignment Notice") containing such information
about the proposed assignee or sublessee, including the proposed use of the
Premises and any Hazardous Materials proposed to be used or stored in the
Premises, the Assignment Date, any relationship between Tenant and the proposed
assignee or sublessee, and all material terms and conditions of the proposed
assignment or sublease, including a copy of any proposed sublease in its final
form, and such other information as Landlord may deem reasonably necessary or
appropriate to its consideration whether to grant its consent. Landlord may, by
giving written notice to Tenant within 15 business days after receipt of the
Assignment Notice:
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(i) grant or refuse such consent, in its sole discretion with respect to a
proposed assignment, hypothecation or other transfer or subletting of more than
(together with all other then effective subleases) 50% of the Premises, or grant
or refuse such consent, in its reasonable discretion with respect to a proposed
subletting of up to (together with all other then effective subleases) 50% of
the Premises (provided that Landlord shall further have the right to review and
approve or disapprove the proposed form of sublease prior to the effective date
of any such subletting), or (ii) terminate this Lease with respect to the space
described in the Assignment Notice, as of the Assignment Date (an "Assignment
Termination"). If Landlord elects an Assignment Termination, Tenant shall have
the right to withdraw such Assignment Notice by written notice to Landlord of
such election within 5 business days after Landlord's notice electing to
exercise the Assignment Termination. If Tenant withdraws such Assignment Notice,
this Lease shall continue in full force and effect. If Tenant does not withdraw
such Assignment Notice, this Lease, and the term and estate herein granted,
shall terminate as of the Assignment Date with respect to the space described in
such Assignment Notice. No failure of Landlord to exercise any such option to
terminate this Lease shall be deemed to be Landlord's consent to the proposed
assignment, sublease or other transfer. Tenant shall reimburse Landlord for all
of Landlord's reasonable out-of-pocket expenses in connection with its
consideration of any Assignment Notice. Notwithstanding the foregoing, (i)
Landlord's consent to an assignment of this Lease or a subletting of any portion
of the Premises to any entity controlling, controlled by or under common control
with Tenant shall not be required, provided that Landlord shall have the right
to approve the form of any such sublease or assignment, and (ii) Tenant shall
have the right to assign this Lease, upon 30 days prior written notice to
Landlord but without obtaining Landlord's prior written consent, to a
corporation or other entity which is a successor-in-interest to Tenant, by way
of merger, consolidation or corporate reorganization, or by the purchase of all
or substantially all of the assets or the ownership interests of the Tenant
provided that (i) such merger or consolidation, or such acquisition or
assumption, as the case may be, is for a good business purpose and not
principally for the purpose of transferring the Lease, and (ii) the net worth
(as determined in accordance with GAAP) of the assignee is not less than the net
worth (as determined in accordance with GAAP) of Tenant as of the Effective
Date, and (iii) such assignee shall agree in writing to assume all of the terms,
covenants and conditions of this Lease arising after the effective date of the
assignment (either (i) or (ii), a "Permitted Assignment").

          (c)  Additional Conditions. As a condition to any such assignment or
subletting, whether or not Landlord's consent is required, Landlord may require:

               (i)  that any assignee or subtenant agree, in writing at the time
of such assignment or subletting, that if Landlord gives such party notice that
Tenant is in default under this Lease, such party shall thereafter make all
payments otherwise due Tenant directly to Landlord, which payments will be
received by Landlord without any liability except to credit such payment against
those due under the Lease, and any such third party shall agree to attorn to
Landlord or its successors and assigns should this Lease be terminated for any
reason; provided, however, in no event shall Landlord or its successors or
assigns be obligated to accept such attornment; and

               (ii) A list of Hazardous Materials, certified by the proposed
assignee or sublessee to be true and correct, which the proposed assignee or
sublessee intends to use or store in the Premises together with copies of all
documents relating to the handling, storage,
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disposal and emission of Hazardous Materials by the proposed assignee or
subtenant in the Premises or on the Project, prior to the proposed assignment or
subletting, including, without limitation: permits; approvals; reports and
correspondence; storage and management plans; plans relating to the installation
of any storage tanks to be installed in or under the Project (provided, said
installation of tanks shall only be permitted after Landlord has given its
written consent to do so, which consent may be withheld in Landlord's sole and
absolute discretion); and all closure plans or any other documents required by
any and all federal, state and local governmental agencies and authorities for
any storage tanks installed in, on or under the Project for the closure of any
such tanks. Neither Tenant nor any such proposed assignee or subtenant is
required, however, to provide Landlord with any portion(s) of the such documents
containing information of a proprietary nature which, in and of themselves, do
not contain a reference to any Hazardous Materials or hazardous activities.

          (d)  No Release of Tenant, Sharing of Excess Rents. Notwithstanding
any assignment or subletting, Tenant and any guarantor or surety of Tenant's
obligations under this Lease shall at all times remain fully and primarily
responsible and liable for the payment of Rent and for compliance with all of
Tenant's other obligations under this Lease. If the Rent due and payable by a
sublessee or assignee (or a combination of the rental payable under such
sublease or assignment plus any bonus or other consideration therefor or
incident thereto) exceeds the rental payable under this Lease, (excluding
however, any Rent payable under this Section), then Tenant shall be bound and
obligated to pay Landlord as Additional Rent hereunder 50% of such excess rental
and other excess consideration within 10 days following receipt thereof by
Tenant. If Tenant shall sublet the Premises or any part thereof, Tenant hereby
immediately and irrevocably assigns to Landlord, as security for Tenant's
obligations under this Lease, all rent from any such subletting and Landlord as
assignee and as attorney-in-fact for Tenant, or a receiver for Tenant appointed
on Landlord's application, may collect such rent and apply it toward Tenant's
obligations under this Lease; except that, until the occurrence of a Default,
Tenant shall have the right to collect such rent.

          (e)  No Waiver. The consent by Landlord to an assignment or subletting
shall not relieve Tenant or any assignees of this Lease or any sublessees of the
Premises from obtaining the consent of Landlord to any further assignment or
subletting nor shall it release Tenant or any assignee or sublessee of Tenant
from full and primary liability under the Lease. The acceptance of Rent
hereunder, or the acceptance of performance of any other term, covenant, or
condition thereof, from any other person or entity shall not be deemed to be a
waiver of any of the provisions of this Lease or a consent to any subletting,
assignment or other transfer of the Premises.

     23.  Estoppel Certificate. Tenant shall within 10 business days of written
notice from Landlord, execute, acknowledge and deliver a statement in writing
substantially in the form attached to this Lease as Exhibit G with the blanks
filled in, and on any other form reasonably requested by a proposed lender or
purchaser, (i) certifying 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 so modified is in full force and effect) and the dates to
which the rental and other charges are paid in advance, if any, (ii)
acknowledging that there are not any uncured defaults on the part of Landlord
hereunder, or specifying such defaults if any are claimed, and (iii) setting
forth such further information with respect to the status of this Lease or the
Premises as may be
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requested thereon. Any such statement may be relied upon by any prospective
purchaser or encumbrancer of all or any portion of the real property of which
the Premises are a part. Tenant's failure to deliver such statement within such
time shall, at the option of Landlord and subject to Section 20(g) hereof,
constitute a Default under this Lease, and, in any event, shall be conclusive
upon Tenant that the Lease is in full force and effect and without modification
except as may be represented by Landlord in any certificate prepared by Landlord
and delivered to Tenant for execution.

     24.  Quiet Enjoyment. So long as Tenant shall perform all of the covenants
and agreements herein required to be performed by Tenant, Tenant shall, subject
to the terms of this Lease, at all times during the Term, have peaceful and
quiet enjoyment of the Premises against any person claiming by, through or under
Landlord.

     25.  Prorations. All prorations required or permitted to be made hereunder
shall be made on the basis of a 360 day year and 30 day months.

     26.  Rules and Regulations. Tenant shall, at all times during the Term and
any extension thereof, comply with all reasonable rules and regulations at any
time or from time to time established by Landlord covering use of the Premises
and the Project. The current rules and regulations are attached hereto as
Exhibit E. If there is any conflict between said rules and regulations and other
provisions of this Lease, the terms and provisions of this Lease shall control.
Landlord shall not have any liability or obligation for the breach of any rules
or regulations by other tenants in the Project.

     27.  Subordination. This Lease and Tenant's interest and rights hereunder
are and shall be subject and subordinate at all times to the lien of any
Mortgage, now existing or hereafter created on or against the Project or the
Premises, and all amendments, restatements, renewals, modifications,
consolidations, refinancing, assignments and extensions thereof, without the
necessity of any further instrument or act on the part of Tenant; provided,
however, that so long as there is no Default hereunder, Tenant's right to
possession of the Premises shall not be disturbed by the Holder of any such
Mortgage. Tenant agrees, at the election of the Holder of any such Mortgage, to
attorn to any such Holder. Tenant agrees upon demand to execute, acknowledge and
deliver a Subordination, Non-disturbance and Attornment Agreement in the form
attached hereto as Exhibit H, or such other instruments, confirming such
subordination and such instruments of attornment as shall be requested by any
such Holder, provided any such instruments contain appropriate non-disturbance
provisions assuring Tenant's quiet enjoyment of the Premises as set forth in
Section 24 hereof. Notwithstanding the foregoing, any such Holder may at any
time subordinate its Mortgage to this Lease, without Tenant's consent, by notice
in writing to Tenant, and thereupon this Lease shall be deemed prior to such
Mortgage without regard to their respective dates of execution, delivery or
recording and in that event such Holder shall have the same rights with respect
to this Lease as though this Lease had been executed prior to the execution,
delivery and recording of such Mortgage and had been assigned to such Holder.
The term "Mortgage" whenever used in this Lease shall be deemed to include deeds
of trust, security assignments and any other encumbrances, and any reference to
the "Holder" of a mortgage shall be deemed to include the beneficiary under a
deed of trust.
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     28.  Surrender. Upon expiration of the Term or earlier termination of
Tenant's right of possession, Tenant shall surrender the Premises to Landlord in
the same condition as received, subject to any Alterations permitted by Landlord
or this Lease to remain in the Premises, free of Hazardous Materials brought
upon, kept or used in or about the Premises by any person other than Landlord,
its agents, employees, contractors or invitees, released of all Use Clearances,
and broom clean, ordinary wear and tear and casualty loss and condemnation
covered by Sections 18 and 19 excepted. Tenant shall immediately return to
Landlord all keys and/or access cards to parking, the Project, restrooms or all
or any portion of the Premises furnished to, or otherwise procured by Tenant. If
any such access card or key is lost, Tenant shall pay to Landlord, at Landlord's
election, either the cost of replacing such lost access card or key or the cost
of reprogramming the access security system in which such access card was used
or changing the lock or locks opened by such lost key. Any Tenant's Property,
Alterations and property not so removed by Tenant as permitted or required
herein shall be deemed abandoned and may be stored, removed, and disposed of by
Landlord at Tenant's expense, and Tenant waives all claims against Landlord for
any damages resulting from Landlord's retention and/or disposition of such
property. All obligations of Tenant hereunder not fully performed as of the
termination of the Term, including the obligations of Tenant under Section 30
hereof, shall survive the expiration or earlier termination of the Term,
including without limitation, indemnity obligations, payment obligations with
respect to Rent and obligations concerning the condition and repair of the
Premises.

     29.  Waiver of Jury Trial. TENANT AND LANDLORD WAIVE ANY RIGHT TO TRIAL BY
JURY OR TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN
CONTRACT, TORT, OR OTHERWISE, BETWEEN LANDLORD AND TENANT ARISING OUT OF THIS
LEASE OR ANY OTHER INSTRUMENT, DOCUMENT, OR AGREEMENT EXECUTED OR DELIVERED IN
CONNECTION HEREWITH OR THE TRANSACTIONS RELATED HERETO.

     30.  Environmental Requirements.

          (a)  Prohibition/Compliance. Except for Hazardous Material contained
in products used by Tenant in de minimis quantities for ordinary cleaning and
office purposes or contained in products used for fire suppression, Tenant shall
not permit or cause any party to bring any Hazardous Material upon the Premises
or the Project or transport, store, use, generate, manufacture or release any
Hazardous Material in or about the Premises or the Project without Landlord's
prior written consent which may be withheld in Landlord's sole discretion.
Tenant, at its sole cost and expense, shall operate its business in the Premises
in strict compliance with all Environmental Requirements and shall remediate in
a manner satisfactory to Landlord any Hazardous Materials released on or from
the Project by Tenant, its agents, employees, contractors, subtenants or
invitees. Tenant shall complete and certify to disclosure statements as
requested by Landlord from time to time relating to Tenant's transportation,
storage, use, generation, manufacture or release of Hazardous Materials on the
Premises. The term "Environmental Requirements" means all applicable present and
future statutes, regulations, ordinances, rules, codes, judgments, orders or
other similar enactments of any governmental authority or agency regulating or
relating to health, safety, or environmental conditions on, under, or about the
Premises or the environment, including without limitation, the following: the
Comprehensive Environmental Response, Compensation and Liability Act; the
Resource
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Conservation and Recovery Act; and all state and local counterparts thereto, and
any regulations or policies promulgated or issued thereunder. The term
"Hazardous Materials" means and includes any substance, material, waste,
pollutant, or contaminant listed or defined as hazardous or toxic, or regulated
by reason of its impact or potential impact on humans, animals and/or the
environment under any Environmental Requirements, asbestos and petroleum,
including crude oil or any fraction thereof, natural gas liquids, liquefied
natural gas, or synthetic gas usable for fuel (or mixtures of natural gas and
such synthetic gas). As defined in Environmental Requirements, Tenant is and
shall be deemed to be the "operator" of Tenant's "facility" and the "owner" of
all Hazardous Materials brought on the Premises by Tenant, its agents,
employees, contractors or invitees, and the wastes, by-products, or residues
generated, resulting, or produced therefrom.

          (b)  Indemnity. Tenant hereby indemnifies and shall defend and hold
Landlord, its officers, directors, employees, agents and contractors harmless
from any and all claims, judgments, damages, penalties, fines, costs,
liabilities, or losses (including, without limitation, diminution in value of
the Premises or any portion of the Project, damages for the loss or restriction
on use of rentable or usable space or of any amenity of the Premises or the
Project, damages arising from any adverse impact on marketing of space in the
Premises or the Project, and sums paid in settlement of claims, attorneys' fees,
consultant fees and expert fees) which arise during or after the Lease term as a
result of Tenant's breach of its obligations pursuant to Section 30(a). 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 Materials
present in the air, soil or ground water above, on, or under the Premises which
arise during or after the Lease term as a result of Tenant's breach of its
obligations pursuant to Section 30(a). Without limiting the foregoing, if the
presence of any Hazardous Materials on the Premises, the Building, the Project
or any adjacent property, caused or permitted by Tenant results in any
contamination of the Premises, the Project or any adjacent property, Tenant
shall promptly take all actions at its sole expense and in accordance with
applicable law as are necessary to return the Premises, the Project or any
adjacent property, to the condition existing prior to the time of such
contamination, provided that Landlord's approval of such action shall first be
obtained, which approval shall not unreasonably be withheld so long as such
actions would not potentially have any material adverse long-term or short-term
effect on the Premises or the Project.

          (c)  Landlord's Tests. Landlord shall have access to, and a right to
perform inspections and tests of, the Premises to determine Tenant's compliance
with Environmental Requirements, its obligations under this Section 30, or the
environmental condition of the Premises or the Project. Access shall be granted
to Landlord upon Landlord's prior notice to Tenant and at such times so as to
minimize, so far as may be reasonable under the circumstances, any disturbance
to Tenant's operations. Such inspections and tests shall be conducted at
Landlord's expense, unless such inspections or tests reveal that Tenant has not
complied with any Environmental Requirement, in which case Tenant shall
reimburse Landlord for the reasonable cost of such inspection and tests.
Landlord's receipt of or satisfaction with any environmental assessment in no
way waives any rights that Landlord holds against Tenant.
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          (d)  Tenant's Obligations. Tenant's obligations under this Article 30
shall survive the expiration or earlier termination of the Lease. During any
period of time after the expiration or earlier termination of this Lease
required by Tenant or Landlord to complete the removal from the Premises of any
Hazardous Materials and the release and termination of any licenses or permits
restricting the use of the Premises, Tenant shall continue to pay the full Rent
in accordance with this Lease for any portion of the Premises not relet by
Landlord in Landlord's sole discretion, which Rent shall be prorated daily.

          (e)  Landlord's AOM Plan. Landlord shall prepare and deliver to
Tenant, within 30 days of the date hereof, an Asbestos Operation and Maintenance
Plan with respect to the non-friable asbestos present in the floor tile mastic
in the Premises.

     31.  Tenant's Remedies/Limitation of Liability. Landlord shall not be in
default hereunder unless Landlord fails to perform any of its obligations
hereunder within 30 days after written notice from Tenant specifying such
failure (unless Landlord has failed to pay a sum of money when due, in which
case Landlord shall have 10 days in which to effect a cure by paying such sum,
or unless the performance of Landlord's obligations will, due to the nature of
the obligations, require a period of time in excess of 30 days, in which case
Landlord shall have such period of time as is reasonably necessary to effect a
cure). Upon any default by Landlord, Tenant shall give notice by registered or
certified mail to any Holder of a Mortgage covering the Premises and to any
landlord of any lease of property in or on which the Premises are located and
Tenant shall offer such beneficiary, Holder and/or landlord a reasonable
opportunity to cure the default, including time to obtain possession of the
Project by power of sale or a judicial action if such should prove necessary to
effect a cure; provided Landlord shall have furnished to Tenant in writing the
names and addresses of all such persons who are to receive such notices. All
obligations of Landlord hereunder shall be construed as covenants, not
conditions; and, except as may be otherwise expressly provided in this Lease,
Tenant may not terminate this Lease for breach of Landlord's obligations
hereunder.

     All obligations of Landlord under this Lease will be binding upon Landlord
only with respect to the obligations accruing during the period of its ownership
of the Premises and not thereafter.  The term "Landlord" in this Lease shall
mean only the owner, for the time being of the Premises, and upon the transfer
by such owner of its interest in the Premises, such owner shall thereupon be
released and discharged from all obligations of Landlord thereafter accruing,
but such obligations shall be binding during the Term upon each new owner for
the duration of such owner's ownership; including, without limitation, such new
owner's obligation to provide Tenant with peaceful and quiet enjoyment of the
Premises as provided in Section 24.

     32.  Inspection and Access. Subject to the provisions of this Section 32,
Landlord and its agents, representatives, and contractors may enter the Premises
at any reasonable time to inspect the Premises and to make such repairs as may
be required or permitted pursuant to this Lease and for any other business
purpose. Landlord and Landlord's representatives may enter the Premises during
business hours on not less than 48 hours advance written notice (except in the
case of emergencies in which case no such notice shall be required and such
entry may be at any time) for the purpose of effecting any such repairs,
inspecting the Premises, showing the Premises to prospective purchasers and,
during the last year of the Term, to prospective tenants or for any other
business purpose. Landlord may erect a suitable sign on the Premises stating the
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Net Office                         2450 Bayshore Parkway/Equinix, Inc. - Page 27

Premises are available to let or that the Project is available for sale.
Landlord may grant easements, make public dedications, designate Common Areas
and create restrictions on or about the Premises, provided that no such
easement, dedication, designation or restriction materially, adversely affects
Tenant's use or occupancy of the Premises for the Permitted use. At Landlord's
request, Tenant shall execute such instruments as may be necessary for such
easements, dedications or restrictions. Tenant shall at all times, except in the
case of emergencies, have the right to escort Landlord or its agents,
representatives, contractors or guests while the same are in the Premises,
provided such escort does not materially and adversely affect Landlord's access
rights hereunder. The names and employers of persons entering the Premises on
behalf of Landlord in a non-emergency shall be disclosed to Tenant not less than
48 hours in advance in advance of any such inspection.

     33.  Security.  Tenant acknowledges and agrees that security devices and
services, if any, while intended to deter crime may not in given instances
prevent theft or other criminal acts and that Landlord is not providing any
security services with respect to the Premises.  Tenant agrees that Landlord
shall not be liable to Tenant for, and Tenant waives any claim against Landlord
with respect to, any loss by theft or any other damage suffered or incurred by
Tenant in connection with any unauthorized entry into the Premises or any other
breach of security with respect to the Premises.  Tenant shall be solely
responsible for the personal safety of Tenant's officers, employees, agents,
contractors, guests and invitees while any such person is in, on or about the
Premises and/or the Project.  Tenant shall at Tenant's cost obtain insurance
coverage to the extent Tenant desires protection against such criminal acts.

     34.  Force Majeure. Neither Landlord nor Tenant shall not be held
responsible for delays in the performance of its obligations hereunder when
caused by strikes, lockouts, labor disputes, weather, natural disasters,
inability to obtain labor or materials or reasonable substitutes therefor,
governmental restrictions, governmental regulations, governmental controls,
delay in issuance of permits, enemy or hostile governmental action, civil
commotion, fire or other casualty, and other causes beyond the reasonable
control of Landlord or Tenant ("Force Majeure"). Notwithstanding the foregoing,
in no event shall Tenant's inability to pay Rent or to meet its financial
obligations hereunder be deemed to be a cause beyond its control.

     35.  Brokers, Entire Agreement, Amendment. Landlord and Tenant each
represent and warrant that it has not dealt with any broker, agent or other
person (collectively, "Broker") in connection with this transaction and that no
Broker brought about this transaction, other than Cooper/Brady Partnership (dba
CRESA Partners). Landlord and Tenant each hereby agree to indemnify and hold the
other harmless from and against any claims by any other Broker claiming a
commission or other form of compensation by virtue of having dealt with Tenant
or Landlord, as applicable, with regard to this leasing transaction. This Lease
may not be amended except by an instrument in writing signed by both parties
hereto.

     36.  Limitation on Landlord's Liability. NOTWITHSTANDING ANYTHING SET FORTH
HEREIN OR IN ANY OTHER AGREEMENT BETWEEN LANDLORD AND TENANT TO THE CONTRARY:
(A) LANDLORD SHALL NOT BE LIABLE TO TENANT OR ANY OTHER PERSON FOR (AND TENANT
AND EACH SUCH OTHER PERSON ASSUME ALL RISK OF) LOSS, DAMAGE OR INJURY, WHETHER
ACTUAL OR CONSEQUENTIAL TO: TENANT'S PERSONAL PROPERTY OF EVERY KIND AND
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DESCRIPTION, INCLUDING, WITHOUT LIMITATION TRADE FIXTURES, EQUIPMENT, INVENTORY,
SCIENTIFIC RESEARCH, SCIENTIFIC EXPERIMENTS, LABORATORY ANIMALS, PRODUCT,
SPECIMENS, SAMPLES, AND/OR SCIENTIFIC, BUSINESS, ACCOUNTING AND OTHER RECORDS OF
EVERY KIND AND DESCRIPTION KEPT AT THE PREMISES AND ANY AND ALL INCOME DERIVED
OR DERIVABLE THEREFROM; (B) THERE SHALL BE NO PERSONAL RECOURSE TO LANDLORD FOR
ANY ACT OR OCCURRENCE IN, ON OR ABOUT THE PREMISES OR ARISING IN ANY WAY UNDER
THIS LEASE OR ANY OTHER AGREEMENT BETWEEN LANDLORD AND TENANT WITH RESPECT TO
THE SUBJECT MATTER HEREOF AND ANY LIABILITY OF LANDLORD HEREUNDER SHALL BE
STRICTLY LIMITED SOLELY TO LANDLORD'S INTEREST IN THE PROJECT (INCLUDING NET
PROCEEDS OF SALE THEREOF), AND IN NO EVENT SHALL ANY PERSONAL LIABILITY BE
ASSERTED AGAINST LANDLORD IN CONNECTION WITH THIS LEASE NOR SHALL ANY RECOURSE
BE HAD TO ANY OTHER PROPERTY OR ASSETS OF LANDLORD OR ANY OF LANDLORD'S
OFFICERS, EMPLOYEES, AGENTS OR CONTRACTORS.  UNDER NO CIRCUMSTANCES SHALL
LANDLORD OR ANY OF LANDLORD'S OFFICERS, EMPLOYEES, AGENTS OR CONTRACTORS BE
LIABLE FOR INJURY TO TENANTS BUSINESS OR FOR ANY LOSS OF INCOME OR PROFIT
THEREFROM.

     37.  Severability. If any clause or provision of this Lease is illegal,
invalid or unenforceable under present or future laws, then and in that event,
it is the intention of the parties hereto that the remainder of this Lease shall
not be affected thereby. It is also the intention of the parties to this Lease
that in lieu of each clause or provision of this Lease that is illegal, invalid
or unenforceable, there be added, as a part of this Lease, a clause or provision
as similar in terms to such illegal, invalid or unenforceable clause or
provision as may be possible and be legal, valid and enforceable.

     38.  Signs; Exterior Appearance. Tenant shall not, without the prior
written consent of Landlord, which may be granted or withheld in Landlord's sole
discretion: (i) attach any awnings, exterior lights, decorations, balloons,
flags, pennants, banners, painting or other projection to any outside wall of
the Project, (ii) use any curtains, blinds, shades or screens other than
Landlord's standard window coverings, (iii) coat or otherwise sunscreen the
interior or exterior of any windows, (iv) place any bottles, parcels, or other
articles on the window sills, (v) place any equipment, furniture or other items
of personal property on any exterior balcony, (vi) paint, affix or exhibit on
any part of the Premises or the Project any signs, notices, window or door
lettering, placards, decorations, or advertising media of any type which can be
viewed from the exterior of the Premises; provided, however, that subject to
Landlord's reasonable approval and all Legal Requirements, Tenant shall have the
right to erect signs reflecting Tenant's name on the Premises and on the Project
signs designated by Landlord for the use of tenants.

     39.  Miscellaneous.

          (a)  Notices. All notices or other communications between the parties
shall be in writing and shall be deemed duly given upon delivery or refusal to
accept delivery by the addressee thereof if delivered in person, or upon actual
receipt if delivered by reputable overnight guaranty courier, addressed and sent
to the parties at their addresses set forth above.
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Landlord and Tenant may from time to time by written notice to the other
designate another address for receipt of future notices.

          (b)  Joint and Several Liability. If and when included within the term
"Tenant," as used in this instrument, there is more than one person or entity,
each shall be jointly and severally liable for the obligations of Tenant.

          (c)  Financial Information. Tenant shall furnish Landlord with true
and complete copies of (i) Tenant's most recent audited annual financial
statements within 90 days of the end of each of Tenant's fiscal years during the
Term, (ii) Tenant's most recent unaudited quarterly financial statements within
60 days of the end of each of Tenant's first three fiscal quarters of each of
Tenant's fiscal year during the Term, (iii) at Landlord's request from time to
time, updated business plans, including cash flow projections and/or pro forma
balance sheets and income statements, all of which shall be treated by Landlord
as confidential information belonging to Tenant, (iv) corporate brochures and/or
profiles prepared by Tenant for prospective investors, and (v) any other
financial information or summaries that Tenant typically provides to its lenders
or shareholders; provided, however, that with respect to the items described in
clause (iii) above, Tenant may refuse to disclose any information which it in
good faith believes to be a trade secret or which it may not lawfully disclose
at such time.

          (d)  Recordation. Neither this Lease nor a memorandum of lease shall
be filed by or on behalf of Tenant in any public record. Landlord may prepare
and file, and upon request by Landlord Tenant will execute, a memorandum of
lease.

          (e)  Interpretation. The normal rule of construction to the effect
that any ambiguities are to be resolved against the drafting party shall not be
employed in the interpretation of this Lease or any exhibits or amendments
hereto. Words of any gender used in this Lease shall be held and construed to
include any other gender, and words in the singular number shall be held to
include the plural, unless the context otherwise requires. The captions inserted
in this Lease are for convenience only and in no way define, limit or otherwise
describe the scope or intent of this Lease, or any provision hereof, or in any
way affect the interpretation of this Lease.

          (f)  Not Binding Until Executed. The submission by Landlord to Tenant
of this Lease shall have no binding force or effect, shall not constitute an
option for the leasing of the Premises, nor confer any right or impose any
obligations upon either party until execution of this Lease by both parties.

          (g)  Limitations on Interest. It is expressly the intent of Landlord
and Tenant at all times to comply with applicable law governing the maximum rate
or amount of any interest payable on or in connection with this Lease. If
applicable law is ever judicially interpreted so as to render usurious any
interest called for under this Lease, or contracted for, charged, taken,
reserved, or received with respect to this Lease, then it is Landlord's and
Tenant's express intent that all excess amounts theretofore collected by
Landlord be credited on the applicable obligation (or, if the obligation has
been or would thereby be paid in full, refunded to Tenant), and the provisions
of this Lease immediately shall be deemed reformed and the amounts thereafter
collectible hereunder reduced, without the necessity of the execution of any new
document, so as
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Net Office                         2450 Bayshore Parkway/Equinix, Inc. - Page 30

to comply with the applicable law, but so as to permit the recovery of the
fullest amount otherwise called for hereunder.

          (h)  Choice of Law. Construction and interpretation of this Lease
shall be governed by the internal laws of the state in which the Premises are
located, excluding any principles of conflicts of laws.

          (i)  Time. Time is of the essence as to the performance of Landlord's
and Tenant's obligations under this Lease.

          (j)  Incorporation by Reference. All exhibits and addenda attached
hereto are hereby incorporated into this Lease and made a part hereof. If there
is any conflict between such exhibits or addenda and the terms of this Lease,
such exhibits or addenda shall control.

          (k)  Confidentiality. Except as required by applicable law or court
order, Landlord and Tenant shall not distribute this Lease or disclose any of
the terms hereof to any third party other than their respective insurers, banks
and other financing sources, prospective purchasers or investors, prospective
assignees or subtenants, officers, directors, employees and consultants
("Permitted Parties"). Landlord and Tenant shall inform their respective
Permitted Parties of this confidentiality provision and shall be liable to the
other party hereto for any breach of this confidentiality provision by such
Permitted Parties.
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     IN WITNESS WHEREOF, Landlord and Tenant have executed this Lease as of the
day and year first above written.

                              TENANT:

                              EQUINIX, INC.,
                              a Delaware corporation

                              By:  /s/ Philip J. Koen
                                   --------------------------------
                              Its: CFO
                                   --------------------------------

                              LANDLORD:

                              ARE-2425/2400/2450 GARCIA BAYSHORE, LLC,
                              a Delaware limited liability company

                              By: ALEXANDRIA REAL ESTATE EQUITIES, L.P., a
                                  Delaware limited partnership, sole member

                                  By: ARE-QRS CORP., a Maryland corporation,
                                      general partner

                                      By: ____________________________

[Notary seal]
<PAGE>

Net Office                         2450 Bayshore Parkway/Equinix, Inc. - Page 32

                              EXHIBIT A TO LEASE

                            DESCRIPTION OF PREMISES
                            -----------------------

                            [Graphic of Floor Plan]
<PAGE>

Net Office                         2450 Bayshore Parkway/Equinix, Inc. - Page 33

                                   EXHIBIT B

                            DESCRIPTION OF PROJECT
                            ----------------------

The land upon which the Project is situated is located in the City of Mountain
View, County of Santa Clara, State of California, described as follows:

All of Parcel 3, as shown upon that certain Map entitled "Parcel Map being a
portion of Rancho De San Francisquito", which Map was filed for Record in the
Office of the Recorder of the County of Santa Clara, State of California, on
March 23, 1981, in Book 481 of Maps, at Pages 27 and 28.

[The foregoing legal description does not include any easements that may be
appurtenant to either the fee interest or the leasehold interest in such real
property]

The Project is depicted on the attached site map; the Premises are those areas
that have been cross-hatched.
<PAGE>

Net Office                         2450 Bayshore Parkway/Equinix, Inc. - Page 34

                                   EXHIBIT B

                             DESCRIPTION OF PROJECT
                             ----------------------

                    [Graphic of Site Map]
<PAGE>

Major Construction - Tenant Build   2450 Bayshore Parkway/Equinix, Inc. - Page 2

                              EXHIBIT C TO LEASE

                                  WORK LETTER
                                  -----------

     THIS WORK LETTER dated January 28, 2000 (this "Work Letter") is made and
entered into by and between ARE-2425/2400/2450 Garcia Bayshore, LLC, a Delaware
limited liability company ("Landlord"), and Equinix, Inc., a Delaware
corporation ("Tenant"), and is attached to and made a part of the Lease dated
January 28, 2000 (the "Lease"), by and between Landlord and Tenant.  Any
initially capitalized terms used but not defined herein shall have the meanings
given them in the Lease.

     1.   General Requirements

          (a)  Tenant's Authorized Representative. Tenant designates Kathleen
Cota and Nancy Escano-Dowler Gruman (either such individual acting alone,
"Tenant's Representative") as the only persons authorized to act for Tenant
pursuant to this Work Letter. Landlord shall not be obligated to respond to or
act upon any request, approval, inquiry or other communication ("Communication")
from or on behalf of Tenant in connection with this Work Letter unless such
Communication is in writing from Tenant's Representative. Tenant may change
Tenant's Representatives at any time upon not less than 5 business days advance
written notice to Landlord. No period set forth herein for any approval of any
matter by Tenant's Representative shall be extended by reason of any change in
Tenant's Representative.

          (b)  Landlord's Authorized Representative. Landlord designates Vin
Ciruzzi and Radika Ratna (either such individual acting alone, "Landlord's
Representative") as the only persons authorized to act for Landlord pursuant to
this Work Letter. Tenant shall not be obligated to respond to or act upon any
request, approval, inquiry or other Communication from or on behalf of Landlord
in connection with this Work Letter unless such Communication is in writing from
Landlord's Representative. Landlord may change Landlord's Representatives at any
time upon not less than 5 business days advance written notice to Tenant. No
period set forth herein for any approval of any matter by Landlord's
Representative shall be extended by reason of any change in Landlord's
Representative. Neither Landlord nor Landlord's Representative shall be
authorized to direct Tenant's contractors in the performance of Tenant's Work
(as hereinafter defined).

          (c)  Architects, Consultants and Contractors. Landlord and Tenant
hereby acknowledge and agree that the architect (the "TI Architect") for the
Tenant Improvements, the general contractor and any subcontractors for the
Tenant Improvements shall be selected by Tenant, subject to Landlord's approval,
which approval shall not be unreasonably withheld, conditioned or delayed.

          (d)  Development Schedule. The proposed schedule for design and
development of Tenant's Improvements (as defined below), including without
limitation the time periods for delivery of construction documents and
performance, shall be generally in accordance with the Development Schedule
attached hereto as Schedule A, subject to such
<PAGE>

Major Construction - Tenant Build   2450 Bayshore Parkway/Equinix, Inc. - Page 3

changes as Tenant shall reasonably require or as provided in this Work Letter
(the "Development Schedule").

     2.   Tenant Improvements.

          (a)  Tenant Improvements Defined. As used herein, "Tenant
Improvements" shall mean all improvements to the Premises desired by Tenant of a
fixed and permanent nature. Other than funding the TI Allowance (as defined
below) as provided herein, Landlord shall not have any obligation whatsoever
with respect to the finishing of the Premises for Tenant's use and occupancy.

          (b)  Tenant's Space Plans. Tenant shall deliver to Landlord schematic
drawings and outline specifications (the "TI Design Drawings") detailing
Tenant's requirements for the Tenant Improvements within 15 business days of the
date hereof. As promptly as reasonably possible, but in no event more than 5
business days thereafter, Landlord shall deliver to Tenant the written
objections, questions or comments of Landlord and the TI Architect with regard
to the TI Design Drawings. Tenant shall cause the TI Design Drawings to be
revised to address such written comments and shall resubmit said drawings to
Landlord for approval thereafter. Such process shall continue until Landlord has
approved the TI Design Drawings.

          (c)  Working Drawings. Following the approval of the TI Design
Drawings by Landlord, Tenant shall cause the TI Architect to prepare and deliver
to Landlord for review and comment construction plans, specifications and
drawings for the Tenant Improvements ("TI Construction Drawings"), which TI
Construction Drawings shall be prepared substantially in accordance with the TI
Design Drawings. Tenant shall be solely responsible for ensuring that the TI
Construction Drawings reflect Tenant's requirements for the Tenant Improvements.
Landlord shall deliver its written comments on the TI Construction Drawings to
Tenant as promptly as reasonably possible, but in no event more than 5 business
days after Landlord's receipt of the same; provided, however, that Landlord may
not disapprove any matter that is consistent with the TI Design Drawings. Tenant
and the TI Architect shall consider all such comments in good faith and shall,
within 10 business days after receipt, notify Landlord how Tenant proposes to
respond to such comments. Any disputes in connection with such comments shall be
resolved in accordance with Section 2(d) hereof. Provided that the design
reflected in the TI Construction Drawings is consistent with the TI Design
Drawings, Landlord shall approve the TI Construction Drawings submitted by
Tenant. Once approved by Landlord, subject to the provisions of Section 2(d)
below, Tenant shall not materially modify the TI Construction Drawings except as
may be reasonably required in connection with the issuance of the TI Permit and
except as provided in Section 4.

          (d)  Approval and Completion. Upon any dispute regarding the design of
the Tenant Improvements, which is not settled within 5 business days after
notice of such dispute is delivered by one party to the other, Tenant shall make
the final decision regarding the design of the Tenant Improvements, provided
Tenant acts reasonably and such final decision is either consistent with or a
compromise between Landlord's and Tenant's positions with respect to such
dispute, provided further that all costs and expenses resulting from any such
decision by Tenant shall be payable out of the TI Fund, as defined in Section
5(d) below. Any changes to the TI
<PAGE>

Major Construction - Tenant Build   2450 Bayshore Parkway/Equinix, Inc. - Page 4

Construction Drawings following Landlord's and Tenant's approval of same
requested by Tenant shall be processed as provided in Section 4 hereof.

     3.   Performance of Tenant's Work

          (a)  Definition of Tenant's Work. As used herein, "Tenant's Work"
shall mean the work of constructing the Tenant Improvements.

          (b)  Commencement and Permitting of Tenant's Work. Tenant shall
commence construction of the Tenant Improvements upon obtaining a building
permit (time "TI Permit") authorizing the construction of the Tenant
Improvements consistent with the TI Construction Drawings approved by Landlord.
The cost of obtaining the TI Permit shall be payable from the TI Fund. Landlord
shall assist Tenant in obtaining the TI Permit.

          (c)  Restrictions on Demolition of Existing Facilities. The parties
acknowledge that the Premises are currently designed for use as a laboratory
facility. The Tenant's Work will convert the Premises into commercial office
use. Prior to commencement of demolition of the current fixtures and equipment
in place in the Premises (the "Existing Facilities"), Tenant shall obtain
Landlord's consent, identifying any part of the Existing Facilities Tenant
intends to demolish or remove. Landlord shall have a reasonable opportunity to
remove, at Landlord's expense, the Existing Facilities prior to the commencement
of Tenant's Work, provided that Landlord's removal of the Existing Facilities
does not unreasonably interfere with or delay Tenant's Work.

          (d)  Selection of Materials, Etc. Where more than one type of material
or structure is indicated on the TI Construction Drawings approved by Tenant and
Landlord, the option will be within Tenant's reasonable discretion.

     4.   Changes. Any changes (other than Minor Variations) requested by Tenant
to the Tenant Improvements after the delivery and approval by Landlord of the TI
Design Drawings, shall be requested and instituted in accordance with the
provisions of this Section 4 and shall be subject to the written approval of
Landlord, such approval not to be unreasonably withheld, conditioned or delayed.

          (a)  Tenant's Right to Request Changes. If Tenant shall request
changes ("Changes"), Tenant shall request such Changes by notifying Landlord in
writing in substantially the same form as the AIA standard change order form (a
"Change Request"), which Change Request shall detail the nature and extent of
any such Change. Such Change Request must be signed by Tenant's Representative.
Landlord shall review and approve or disapprove such Change Request as soon as
reasonably possible, but in any event within 5 business days thereafter,
provided that Landlord's approval shall not be unreasonably withheld,
conditioned or delayed.

          (b)  Implementation of Changes. If Landlord approves such Change,
Tenant may cause the approved Change to be instituted.
<PAGE>

Major Construction - Tenant Build   2450 Bayshore Parkway/Equinix, Inc. - Page 5

     5.   Costs

          (a)  Budget For Tenant Improvements. Before the commencement of
construction of the Tenant Improvements, Tenant shall obtain a detailed
breakdown, by trade, of the costs incurred or which will be incurred, in
connection with the design and construction of Tenant's Work (the "Budget"). The
Budget shall be based upon the TI Construction Drawings approved by Landlord and
shall include a payment to Landlord, of administrative rent ("Administrative
Rent") equal to 5.0% of the TI Costs (as hereinafter defined) for monitoring and
inspecting the construction of Tenant's Work, which sum shall be payable from
the TI Fund. Such Administrative Rent shall include, without limitation, all
out-of-pocket costs, expenses and fees incurred by or on behalf of Landlord
arising from, out of, or in connection with, such monitoring of the construction
of the Tenant's Improvements, and shall be payable out of the TI Fund.

          (b)  TI Allowance. Landlord shall provide to Tenant improvement
allowances (collectively, the "TI Allowance") as follows:

               (i)  a "Tenant Improvement Allowance" in the maximum amount of
$20.00 per rentable square foot in the Premises which is included in the Base
Rent set forth in the Lease; and

               (ii) an "Additional Tenant Improvement Allowance" in the maximum
amount of $5.00 per rentable square foot in the Premises which shall, if and to
the extent used, result in adjustments to the Base Rent as set forth in the
Lease.

Before commencing any Tenant's Work, Tenant shall notify Landlord in writing how
much Additional Tenant Improvement Allowance, if any, Tenant has elected to
receive from Landlord.  Such election shall be final and binding on Tenant, and
may not thereafter be modified without Landlord's consent, which may granted or
withheld in Landlord's sole and absolute discretion.  The TI Allowance shall be
disbursed in accordance with this Work Letter.

          (c)  Costs Includable in TI Fund. The TI Fund shall be used solely for
the payment of design and construction costs in connection with the construction
of the Tenant Improvements, including, without limitation, the cost of preparing
the TI Design Drawings and the TI Construction Drawings, all costs set forth in
the Budget, including data and telecommunications cabling, Landlord's
Administrative Rent and the cost of Changes (collectively, "TI Costs").
Notwithstanding anything to the contrary contained herein, the TI Fund shall not
be used to purchase any furniture, personal property or other non-building
system materials or equipment.

          (d)  Excess TI Costs. It is understood and agreed that Landlord is
under no obligation to bear any portion of the cost of any of the Tenant
Improvements except to the extent of the TI Allowance. The funds required to be
paid by Tenant for Tenant's Work, together with the remaining TI Allowance, is
herein referred to as the "TI Fund". Notwithstanding anything to the contrary
set forth in this Section 5(d), Tenant shall be fully and solely liable for TI
Costs and the cost of Minor Variations in excess of the TI Allowance.
<PAGE>

Major Construction - Tenant Build   2450 Bayshore Parkway/Equinix, Inc. - Page 6

          (e)  Payment for TI Costs. Landlord shall disburse the TI Allowance
once a month against a draw request providing the information described in
Schedule B. attached hereto, to the extent of Landlord's approval thereof for
payment, no later than 30 days following receipt of such draw request.

     6.   Miscellaneous

          (a)  Consents. Whenever consent or approval of either party is
required under this Work Letter, that party shall not unreasonably withhold,
condition or delay such consent or approval, except as may be expressly set
forth herein to the contrary.

          (b)  Modification. No modification, waiver or amendment of this Work
Agreement or of any of its conditions or provisions shall be binding upon
Landlord or Tenant unless in writing signed by Landlord and Tenant.

          (c)  Counterparts. This Work Letter may be executed in any number of
counterparts but all counterparts taken together shall constitute a single
document.

          (d)  Governing Law. This Work Letter shall be governed by, construed
and enforced in accordance with the internal laws of the state in which the
Premises are located, without regard to choice of law principles of such State.

          (e)  Time of the Essence. Time is of the essence of this Work
Agreement and of each and all provisions thereof.

          (f)  Default. Notwithstanding anything set forth herein or in the
Lease to the contrary, Landlord shall not have any obligation to perform any
work hereunder or to fund any portion of the TI Fund during any period Tenant is
in Default under the Lease.

          (g)  Severability. If any term or provision of this Work Letter is
declared invalid or unenforceable, the remainder of this Work Letter shall not
be affected by such determination and shall continue to be valid and
enforceable.

          (h)  Merger. All understandings and agreements, oral or written,
heretofore made between the parties hereto and relating to Landlord's Work are
merged in this Work Letter, which alone (but inclusive of provisions of the
Lease incorporated herein and the final approved constructions drawings and
specifications prepared pursuant hereto) fully and completely expresses the
agreement between Landlord and Tenant with regard to the makers set forth in
this Work Letter.

          (i)  Entire Agreement. This Work Letter is made as a part of and
pursuant to the Lease and, together with the Lease, constitutes the entire
agreement of the parties with respect to the subject maker hereof. This Work
Letter is subject to all of the terms and limitation set forth in the Lease, and
neither party shall have any rights or remedies under this Work Letter separate
and apart from their respective remedies pursuant to the Lease.
<PAGE>

Major Construction - Tenant Build   2450 Bayshore Parkway/Equinix, Inc. - Page 2

     IN WITNESS WHEREOF, Landlord and Tenant have executed this Work Letter to
be effective on the date first above written.

                         TENANT:

                         EQUINIX, INC.,
                         a Delaware corporation

                         By:  /s/ Philip J. Koen
                              ------------------
                         Its:  CFO
                               -----------------

                         LANDLORD:

                         ARE-2425/2400/2450 GARCIA BAYSHORE, LLC,
                         a Delaware limited liability company

                         By:  ALEXANDRIA REAL ESTATE EQUITIES, L.P., a
                              Delaware limited partnership, sole member

                              By: ARE-QRS CORP., a Maryland corporation,
                                  general partner

                                    By:______________________________

[Notary seal]
<PAGE>

Major Construction - Tenant Build   2450 Bayshore Parkway/Equinix, Inc. - Page 2

                           SCHEDULE A TO WORK LETTER

                             Development Schedule
                             --------------------

Event                                                         Date
-----                                                         ----

Execution of lease                                          __/__/__

Naming of Tenant's Representatives                          __/__/__

Delivery of space plans for TI Design Drawings
pursuant to Section 2(b) of the Work Letter                 2/9/00

Delivery of Preliminary TI Plans for
pursuant to Section 2(c) of the Work Letter                 2/16/00

Delivery of TI Construction Drawings
pursuant to Section 2(d) of the Work Letter                 3/8/00

Commence construction of Tenant Improvements                3/1/00

Substantial Completion of Tenant Improvements               6/5/00

Issuance of Temporary Certificate of Occupancy              6/16/00
<PAGE>

Major Construction - Tenant Build   2450 Bayshore Parkway/Equinix, Inc. - Page 2

                           SCHEDULE B TO WORK LETTER

     1.   Before any work is begun, Landlord shall have received a fully
executed copy of the construction contract for the Tenant Improvements and a
certificate of insurance complying with the terms of the Lease including with
respect to the construction of the Tenant Improvements.

     2.   For each progress payment AIA Forms G702 and G703(a), together with
Civil Code Section 3262 conditional lien waivers and lien releases for any work
done and previously paid for, invoices, inspection reports and such other
relevant documents as Landlord may reasonably require.

     3.   For the final draw, an AIA Form G704 Certificate of Substantial
Completion executed by both the TI Architect and the TI contractor, together
with final lien releases, final inspection reports, a certificate of occupancy
for the Premises and such other makers as Landlord may reasonably require.
<PAGE>

Commencement Date                   2450 Bayshore Parkway/Equinix, Inc. - Page 1

                              EXHIBIT D TO LEASE

                      ACKNOWLEDGMENT OF COMMENCEMENT DATE

     This ACKNOWLEDGMENT OF COMMENCEMENT DATE is made this _____ day of
__________, 2000, between ARE-2425/2400/2450 Garcia Bayshore, LLC, a Delaware
limited liability company ("Landlord"), and Equinix, Inc., a Delaware
corporation ("Tenant"), and is attached to and made a part of the Lease dated
January 28, 2000 (the "Lease"), by and between Landlord and Tenant.  Any
                       -----
initially capitalized terms used but not defined herein shall have the meanings
given them in the Lease.

     Landlord and Tenant hereby acknowledge and agree, for all purposes of the
Lease, that the Commencement Date of the Base Term of the Lease is
__________,2000, and the termination date of the Base Term of the Lease shall be
midnight on __________, _____.

     IN WITNESS WHEREOF, Landlord and Tenant have executed this ACKNOWLEDGMENT
OF COMMENCEMENT DATE to be effective on the date first above written.

                         TENANT:

                         EQUINIX, INC.,
                         a Delaware corporation

                         By:___________________________________
                         Its:

                         LANDLORD:

                         ARE-2425/2400/2450 GARCIA BAYSHORE, LLC,
                         a Delaware limited liability company

                         By: ALEXANDRIA REAL ESTATE EQUITIES, L.P., a
                             Delaware limited partnership, sole member

                             By: ARE-QRS CORP., a Maryland corporation,
                                 general partner

                                    By:________________________
<PAGE>

Rules and Regulations               2450 Bayshore Parkway/Equinix, Inc. - Page 1

                              EXHIBIT E TO LEASE

                             RULES AND REGULATIONS

     1.   The sidewalk, entries, and driveways of the Project shall not be
obstructed by Tenant, or its agents, or used by them for any purpose other than
ingress and egress to and from the Premises.

     2.   Tenant shall not place any objects, including antennas, outdoor
furniture, etc., in the parking areas, landscaped areas or other areas outside
of its Premises, or on the roof of the Project.

     3.   Except for seeing-eye dogs, no animals shall be allowed in the
offices, halls, or corridors in the Project.

     4.   Tenant shall not disturb the occupants of the Project or adjoining
buildings by the use of any radio or musical instrument or by the making of loud
or improper noises.

     5.   If Tenant desires telegraphic, telephonic or other electric
connections in the Premises, Landlord or its agent will direct the electrician
as to where and how the wires may be introduced; and, without such direction, no
boring or cutting of wires will be permitted. Any such installation or
connection shall be made at Tenant's expense.

     6.   Tenant shall not install or operate any steam or gas engine or boiler,
or other mechanical apparatus in the Premises, except as specifically approved
in the Lease.  The use of oil, gas or inflammable liquids for heating, lighting
or any other purpose is expressly prohibited.  Explosives or other articles
deemed extra hazardous shall not be brought into the Project.

     7.   Parking any type of recreational vehicles is specifically prohibited
on or about the Project. Except for the overnight parking of operative vehicles,
no vehicle of any type shall be stored in the parking areas at any time. In the
event that a vehicle is disabled, it shall be removed within 48 hours. There
shall be no "For Sale" or other advertising signs on or about any parked
vehicle. All vehicles shall be parked in the designated parking areas in
conformity with all signs and other markings. All parking will be open parking,
and no reserved parking, numbering or lettering of individual spaces will be
permitted except as specified by Landlord.

     8.   Tenant shall maintain the Premises free from rodents, insects and
other pests.

     9.   Landlord reserves the right to exclude or expel from the Project any
person who, in the judgment of Landlord, is intoxicated or under the influence
of liquor or drugs or who shall in any manner do any act in violation of the
Rules and Regulations of the Project.

     10.  Tenant shall not cause any unnecessary labor by reason of Tenant's
carelessness or indifference in the preservation of good order and cleanliness.
Landlord shall not be responsible to Tenant for any loss of property on the
Premises, however occurring, or for any damage done to the effects of Tenant by
the janitors or any other employee or person.
<PAGE>

Rules and Regulations               2450 Bayshore Parkway/Equinix, Inc. - Page 1

     11.  Tenant shall give Landlord prompt notice of any material defects in
the water, lawn sprinkler, sewage, gas pipes, electrical lights and fixtures,
heating apparatus, or any other service equipment affecting the Premises.

     12.  Tenant shall not permit storage outside the Premises, including
without limitation, outside storage of trucks and other vehicles, or dumping of
waste or refuse or permit any harmful materials to be placed in any drainage
system or sanitary system in or about the Premises.

     13.  All moveable trash receptacles provided by the trash disposal firm for
the Premises must be kept in the trash enclosure areas, if any, provided for
that purpose.

     14.  No auction, public or private, will be permitted on the Premises or
the Project.

     15.  No awnings shall be placed over the windows in the Premises except
with the prior written consent of Landlord.

     16.  The Premises shall not be used for lodging, sleeping or cooking or for
any immoral or illegal purposes or for any purpose other than that specified in
the Lease.  No gaming devices shall be operated in the Premises.

     17.  Tenant shall ascertain from Landlord the maximum amount of electrical
current which can safely be used in the Premises, taking into account the
capacity of the electrical wiring in the Project and the Premises and the needs
of other tenants, and shall not use more than such safe capacity.  Landlord's
consent to the installation of electric equipment shall not relieve Tenant from
the obligation not to use more electricity than such safe capacity.

     18.  Tenant assumes full responsibility for protecting the Premises from
theft, robbery and pilferage.

     19.  Tenant shall not install or operate on the Premises any machinery or
mechanical devices of a nature not directly related to Tenant's ordinary use of
the Premises and shall keep all such machinery free of vibration, noise and air
waves which may be transmitted beyond the Premises.
<PAGE>

Tenant's Personal Property          2450 Bayshore Parkway/Equinix, Inc. - Page 1

                              EXHIBIT F TO LEASE

                          TENANT'S PERSONAL PROPERTY
                          --------------------------

                              [Tenant to Provide]
<PAGE>

Estoppel Certificate                2450 Bayshore Parkway/Equinix, Inc. - Page 1

                              EXHIBIT G TO LEASE

                             ESTOPPEL CERTIFICATE

     THIS TENANT ESTOPPEL CERTIFICATE ("Certificate"), dated as of __________,
_____, is executed by ("Tenant") in favor of [Buyer], a __________, together
with its nominees, designees and assigns (collectively, "Buyer"), and in favor
of __________, together with its nominees, designees and assigns (collectively,
"Lender").

                                   RECITALS
                                   --------

     A.   Buyer and __________ ("Landlord"), have entered into that certain
Purchase and Sale Agreement and Joint Escrow Instructions, dated as of
__________, 20__ (the "Purchase Agreement"), whereby Buyer has agreed to
purchase, among other things, the improved real property located in the City of
__________, County of __________, State of __________, more particularly
described on Exhibit A attached to the Purchase Agreement (the "Property").
             ---------

     B.   Tenant and Landlord have entered into that certain Lease Agreement,
dated as of __________ (together with all amendments, modifications,
supplements, guarantees and restatements thereof, the "Lease"), for a portion of
the Property.

     C.   Pursuant to the Lease, Tenant has agreed that upon the request of
Landlord, Tenant would execute and deliver an estoppel certificate certifying
the status of the Lease.

     D.   In connection with the Purchase Agreement, Landlord has requested that
Tenant execute this Certificate with an understanding that Lender will rely on
the representations and agreements below in granting to Buyer a loan.

     NOW, THEREFORE, Tenant certifies, warrants, and represents to Buyer and
Lender as follows:

     1.   Lease. Attached hereto as Exhibit B is a true, correct and complete
                                    ---------
copy of the Lease, including the following amendments, modifications,
supplements, guarantees and restatements thereof, which together represent all
of the amendments, modifications, supplements, guarantees and restatements
thereof:_______________________________________________________________________
_____________________________________________________________________________.
(If none, please state "None.")

     2.   Premises. Pursuant to the Lease, Tenant leases those certain premises
(the "Premises") consisting of approximately ____________________ rentable
square feet within the Property, as more particularly described in the Lease. In
addition, pursuant to the terms of the Lease, Tenant has the [non-exclusive]
right to use [__________ parking spaces/the parking area] located on the
Property during the term of the Lease. [Cross-out the preceding sentence or
portions thereof if inapplicable.]
<PAGE>

Estoppel Certificate                2450 Bayshore Parkway/Equinix, Inc. - Page 2

     3.   Full Force of Lease. The Lease has been duly authorized, executed and
delivered by Tenant, is in full force and effect, has not been terminated, and
constitutes a legally valid instrument, binding and enforceable against Tenant
in accordance with its terms, subject only to applicable limitations imposed by
laws relating to bankruptcy and creditor's rights.

     4.   Complete Agreement. The Lease constitutes the complete agreement
between Landlord and Tenant for the Premises and the Property, and except as
modified by the Lease Estoppel Certificate amendments noted above (if any), has
not been modified, altered or amended.

     5.   Acceptance of Premises. Tenant has accepted possession and is
currently occupying the Premises.

     6.   Lease Term. The term of the Lease commenced on __________ and ends on
__________, subject to the following options to extend _________________________
_________________________.
(If none, please state "None.")

     7.   Purchase Rights. Tenant has no option, right of first refusal, right
of first offer, or other right to acquire or purchase all or any portion of the
Premises or all or any portion of, or interest in, the Property, except as
follows: _______________________________________________________________________
_______________________________________________________________________________.
(If none, please state "None.")

     8.   Rights of Tenant. Except as expressly stated in this Certificate,
Tenant:

          (a)  has no right to renew or extend the term of the Lease;

          (b)  has no option or other right to purchase all or any part of the
Premises or all or any part of the Property;

          (c)  has no right, title, or interest in the Premises, other than as
Tenant under the Lease .

     9.   Rent.

          (a)  The obligation to pay rent under the Lease commenced on
__________. The rent under the Lease is current, and Tenant is not in default in
the performance of any of its obligations under the Lease.

          (b)  Tenant is currently paying base rent under the Lease in the
amount of $__________ per month. Tenant has not received and is not presently
entitled to any abatement, refunds, rebates, concessions or forgiveness of rent
or other charges, free rent, partial rent, or credits, offsets or reductions in
rent, except as follows: ______________________________________________________
_____________________________________________. (If none, please state "None.")
<PAGE>

Estoppel Certificate                2450 Bayshore Parkway/Equinix, Inc. - Page 3

          (c)  Tenant's estimated share of operating expenses, common area
charges, insurance, real estate taxes and administrative and overhead expenses
is ___% and is currently being paid at the rate of $__________ per month,
payable to: ___________________________________________________________________
_______________________________________.

          (d)  There are no existing defenses or offsets against rent due or to
become due under the terms of the Lease, and there presently is no default or
other wrongful act or omission by Landlord under the Lease or otherwise in
connection with Tenant's occupancy of the Premises, nor is there a state of
facts which with the passage of time or the giving of notice or both could ripen
into a default on the part of Tenant, or to the best knowledge of Tenant, could
ripen into a default on the part of Landlord under the Lease, except as follows:
_______________________________________________________________________________
____________________. (If none, please state "None.")

     10.  Security Deposit. The amount of Tenant's security deposit held by
Landlord under the Lease is $__________.

     11.  Prepaid Rent. The amount of prepaid rent, separate from the security
deposit, is $__________, covering the period from __________ to __________.

     12.  Insurance. All insurance, if any, required to be maintained by Tenant
under the Lease is presently in effect.

     13.  Pending Actions. There is not pending or, to the knowledge of Tenant,
threatened against or contemplated by the Tenant, any petition in bankruptcy,
whether voluntary or otherwise, any assignment for the benefit of creditors, or
any petition seeking reorganization or arrangement under the federal bankruptcy
laws or those of any state.

     14.  Tenant Improvements. As of the date of this Certificate, to the best
of Tenant's knowledge, Landlord has performed all obligations required of
Landlord pursuant to the Lease; no offsets, counterclaims, or defenses of Tenant
under the Lease exist against Landlord; and no events have occurred that, with
the passage of time or the giving of notice, would constitute a basis for
offsets, counterclaims, or defenses against Landlord, except as follows:________
________________________________________________________________________________
______________________________. (If none, please state "None.")

     15.  Assignments by Landlord. Tenant has received no notice of any
assignment, hypothecation or pledge of the Lease or rentals under the Lease by
Landlord. Tenant hereby consents to an assignment of the Lease and rents to be
executed by Landlord to Buyer or Lender in connection with the Loan and
acknowledges that said assignment does not violate the provisions of the Lease.
Tenant acknowledges that the interest of the Landlord under the Lease is to be
assigned to Buyer or Lender solely as security for the purposes specified in
said assignment and Buyer or Lender shall have no duty, liability or obligation
whatsoever under the Lease or any extension or renewal thereof, either by virtue
of said assignment or by any subsequent receipt or collection of rents
thereunder, unless Buyer or Lender shall specifically undertake such liability
in writing. Tenant agrees that upon receipt of a written notice from
<PAGE>

Estoppel Certificate                2450 Bayshore Parkway/Equinix, Inc. - Page 4

Buyer or Lender of a default by Landlord under the Loan, Tenant will thereafter
pay rent to Buyer or Lender in accordance with the terms of the Lease.

     16.  Assignments by Tenant. Tenant has not sublet or assigned the Premises
or the Lease or any portion thereof to any sublessee or assignee except as
follows: ______________________________________________________________________
______________________________________________________________. No one except
Tenant and its employees will occupy the Premises except as described in the
preceding sentence hereof. The address for notices to be sent to Tenant is as
set forth in the Lease.

     17.  Environmental Matters.  The operation and use of the Premises does not
involve the generation, treatment, storage, disposal or release into the
environment of any hazardous materials, regulated materials and/or solid waste,
except those used in the ordinary course of operating for the Permitted Use, as
defined in the Lease, or otherwise used in accordance with all applicable laws.

     18.  Succession of Interest. Tenant agrees that, in the event Buyer or
Lender succeeds to the interest of Landlord under the Lease:

          (a)  Buyer or Lender shall not be liable for any act or omission of
any prior landlord (including Landlord);

          (b)  Buyer or Lender shall not be liable for the return of any
security deposit;

          (c)  Buyer or Lender shall not be bound by any rent or additional rent
which Tenant might have prepaid under the Lease for more than the current month;

          (d)  Buyer or Lender shall not be bound by any amendments or
modifications of the Lease made without prior consent of Buyer or Lender;

          (e)  Buyer or Lender shall not be subject to any offsets or defenses
which Tenant might have against any prior landlord (including Landlord); or

          (f)  Buyer or Lender shall not be liable under the Lease to Tenant for
the performance of Landlord's obligations under the Lease beyond Buyer or
Lender's interest in the Property.

     19.  Notice of Default. Tenant agrees to give Buyer and Lender a copy of
any notice of default under the Lease served upon Landlord at the same time as
such notice is given to Landlord. Tenant further agrees that if Landlord shall
fail to cure such default within the applicable grace period, if any, provided
in the Lease, then Buyer or Lender shall have an additional 60 days within which
to cure such default, or if such default cannot be cured within such 60-day
period, such 60-day period shall be extended so long as Buyer or Lender has
commenced and is diligently pursuing the remedies necessary to cure such default
(including, but not limited to, commencement of foreclosure proceedings, if
necessary to effect such cure, in which event the Lease shall not be terminated
while such remedies are being pursued.
<PAGE>

Estoppel Certificate                2450 Bayshore Parkway/Equinix, Inc. - Page 5

     20.  Notification by Tenant. From the date of this Certificate and
continuing until __________, Tenant agrees to immediately notify Buyer and
Lender, in writing by registered or certified mail, return receipt requested, at
the following addresses, on the occurrence of any event or the discovery of any
fact that would make any representation contained in this Certificate
inaccurate:

     If To Buyer:        ______________________________

                         ______________________________

                         ______________________________

                         ______________________________

                         ______________________________

     With A Copy To:     ______________________________

                         ______________________________

                         ______________________________

                         ______________________________

                         ______________________________

     If To Lender:       ______________________________

                         ______________________________

                         ______________________________

                         ______________________________

                         ______________________________

     Tenant makes this Certificate with the knowledge that it will be relied
upon by Buyer and Lender in agreeing to purchase the Property.

<PAGE>

Estoppel Certificate               2450 Bayshore Parkway/Equinix, Inc. - Page 1

     Tenant has executed this Certificate as of the date first written above by
the person named below, who is duly authorized to do so.

TENANT:             _______________________________________
                    a______________________________________

                    By: ____________________________________
                        Name:_______________________________
                        Its:________________________________
<PAGE>

Estoppel Certificate               2450 Bayshore Parkway/Equinix, Inc. - Page 1

                       EXHIBIT A TO ESTOPPEL CERTIFICATE

                               Legal Description
                               -----------------
<PAGE>

Estoppel Certificate                2450 Bayshore Parkway/Equinix, Inc. - Page 2

                       EXHIBIT B TO ESTOPPEL CERTIFICATE

                                 Copy of Lease
                                 -------------

<PAGE>

Subordination Agreement            2450 Bayshore Parkway/Equinix, Inc. - Page 1

                              EXHIBIT H TO LEASE

                      SUBORDINATION, NON-DISTURBANCE AND
                             ATTORNMENT AGREEMENT
                             --------------------

     THIS SUBORDINATION, NON-DISTURBANCE AND ATTORNMENT AGREEMENT is made and
entered into as of __________ _____, _____("Agreement"), by and between
ALEXANDRIA REAL ESTATE EQUITIES, INC., a Maryland corporation together with its
nominees, designees and assigns (collectively, "Landlord"),
____________________, a ____________________ ("Tenant"), and _________________,
a ____________________ ("Mortgagee").

     WHEREAS, Mortgagee is making a loan to Landlord and others evidenced by a
certain promissory note ("Note"), and secured by, among other things, a deed of
trust/mortgage to be recorded prior hereto in the public records of the City of
__________, County of __________, State of ("Mortgage") constituting a lien upon
the real property described in Exhibit A hereto (the "Real Property"); and
                               ---------

     WHEREAS, ______________________________ and Tenant have entered into a
Lease Agreement dated as of _______________________, __________ ("Lease"), for
certain leased premises encompassing ______________________________ located in
__________________ , containing approximately ______________________________ net
square feet (hereinafter collectively referred to as "Premises"); and

     WHEREAS, the Lease is subordinate to the Mortgage and to the right, title,
and interests of Mortgagee thereto and thereunder; and

     WHEREAS, Mortgagee wishes to obtain from Tenant certain assurances that
Tenant will attorn to Mortgagee in the event of a foreclosure by Mortgagee or
the exercise of other rights under the Mortgage; and

     WHEREAS, Tenant wishes to obtain from Mortgagee certain assurances that
Tenant's possession of the Premises will not, subject to the terms and
conditions of this Agreement, be disturbed by reason of a foreclosure of the
lien of the Mortgage on the Real Property; and

     WHEREAS, Tenant and Mortgagee are both willing to provide such assurances
to each other upon and subject to the terms and conditions of this Agreement.

     NOW, THEREFORE, in consideration of the above, the mutual promises
hereinafter set forth, and other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, the parties hereto mutually
agree as follows:

     1.   Affirmation. Tenant hereby agrees that the Lease now is and shall be
subject and subordinate in all respects to the Mortgage and to all renewals,
modifications and extensions thereof until such time that the Mortgage is
released, satisfied or otherwise discharged, subject to the terms and conditions
of this Agreement. Landlord and Tenant hereby affirm that the Lease is
<PAGE>

Subordination Agreement            2450 Bayshore Parkway/Equinix, Inc. - Page 2

in full force and effect and that the Lease has not been modified or amended
except as follows:

_____________________________________________________________________________
__________________________________________________.  Mortgagee hereby confirms
that it is the holder of the Note and the beneficiary of the Mortgage and has
full power and authority to enter into this Agreement.

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