<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


                                                                    EXHIBIT 10.8

                                                                  Execution Copy

================================================================================

                                   ----------

                               AGREEMENT OF LEASE

                                   ----------

                       SENTINEL PROPERTIES - BEDFORD, LLC

                                    LANDLORD

                                       AND

                               ATHENAHEALTH, INC.

                                     TENANT

Premises: PART OF
          SENTINEL BEDFORD DATA CENTER
          55 MIDDLESEX TURNPIKE
          BEDFORD, MASSACHUSETTS

Dated:    MAY 8, 2007

================================================================================

CONFIDENTIAL

<PAGE>
*Exhibit has been omitted pursuant to request for CTR
**Portion of Exhibit has been omitted pursuant to request for CTR

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                  Page
                                                                                  ----
<S>   <C>                                                                         <C>
      ARTICLE 1  DEMISE, PREMISES, TERM, RENT..................................     1
      ARTICLE 2  USE AND OCCUPANCY; TENANT'S EQUIPMENT.........................     2
      ARTICLE 3  ALTERATIONS...................................................     2
      ARTICLE 4  CONDITION OF THE PREMISES; INITIAL WORK.......................     3
      ARTICLE 5  REPAIRS AND MAINTENANCE; FLOOR LOAD; SELF-HELP RIGHTS.........     4
      ARTICLE 6  UTILITY EXPENSES..............................................     4
      ARTICLE 7  LEGAL REQUIREMENTS............................................     5
      ARTICLE 8  MORTGAGES; SUBORDINATION; ESTOPPEL CERTIFICATES...............     6
      ARTICLE 9  SERVICES......................................................     7
      ARTICLE 10 INSURANCE.....................................................     8
      ARTICLE 11 DESTRUCTION OF THE PROPERTY; LOSS OR DAMAGE...................     9
      ARTICLE 12 EMINENT DOMAIN................................................    10
      ARTICLE 13 ASSIGNMENT AND SUBLETTING.....................................    10
      ARTICLE 14 ACCESS TO PREMISES............................................    14
      ARTICLE 15 CERTIFICATE OF OCCUPANCY......................................    15
      ARTICLE 16 DEFAULT.......................................................    15
      ARTICLE 17 REMEDIES AND DAMAGES..........................................    17
      ARTICLE 18 FEES AND EXPENSES.............................................    18
      ARTICLE 19 NO REPRESENTATIONS BY LANDLORD................................    18
      ARTICLE 20 END OF TERM...................................................    18
      ARTICLE 21 QUIET ENJOYMENT...............................................    19
      ARTICLE 22 NO WAIVER, NON-LIABILITY......................................    19
      ARTICLE 23 WAIVER OF TRIAL BY JURY.......................................    20
      ARTICLE 24 INABILITY TO PERFORM..........................................    20
      ARTICLE 25 BILLS AND NOTICES.............................................    20
      ARTICLE 26 RULES AND REGULATIONS.........................................    21
      ARTICLE 27 BROKER........................................................    21
      ARTICLE 28 INDEMNITY.....................................................    21
      ARTICLE 29 OFFER SPACE...................................................    22
      ARTICLE 30 EXTENSION OPTION..............................................    23
      ARTICLE 31 [INTENTIONALLY OMITTED].......................................    24
      ARTICLE 32 [INTENTIONALLY OMITTED].......................................    24
      ARTICLE 33 [INTENTIONALLY OMITTED].......................................    24
      ARTICLE 34 EXCULPATION; APPROVALS; LEGAL FEES............................    24
      ARTICLE 35 LANDLORD'S DEFAULT, TENANT'S REMEDIES, SELF-HELP..............    24
      ARTICLE 36 MISCELLANEOUS.................................................    25

    * EXHIBIT A  FLOOR PLAN OF THE PREMISES....................................    A-1
   ** EXHIBIT B  DEFINITIONS...................................................    B-1
      EXHIBIT C  RULES AND REGULATIONS.........................................    C-1
    * EXHIBIT D  REMAINING FIT OUT ITEMS.......................................    D-1
   ** EXHIBIT E  FORM OF SUBORDINATION, NON-DISTURBANCE
                 AND ATTORNMENT AGREEMENT......................................    E-1
    * EXHIBIT F  SERVICE LEVEL AGREEMENT.......................................    F-1
   ** EXHIBIT G  TENANT'S INITIAL AUTHORIZED CONTACTS..........................    G-1
</TABLE>

<PAGE>

                             INDEX OF DEFINED TERMS

<TABLE>
<CAPTION>
Term                                                            Section
----                                                  --------------------------
<S>                                                   <C>
Additional Rent....................................                    Exhibit B
Affiliate..........................................                    Exhibit B
Aggregate Direct Electric Loads....................                  Section 6.1
Alterations........................................                    Exhibit B
Ancillary Utility Costs............................                    Exhibit B
Applicable Offer Space.............................                 Section 29.1
Approval...........................................                    Exhibit B
Approved...........................................                    Exhibit B
Authorized Contacts................................                    Exhibit B
Base Building Restoration..........................   Section 11.1, Section 11.1
Base Rate..........................................                    Exhibit B
Broker.............................................                    Exhibit B
Building...........................................                    Exhibit B
Business Days......................................                    Exhibit B
Commencement Date..................................                    Exhibit B
controlled.........................................                    Exhibit B
controls...........................................                    Exhibit B
Core Building Systems..............................                    Exhibit B
CRAC...............................................               Section 9.2(b)
Data Center Configuration Work.....................                  Section 3.1
Data Center Configuration Work Approval
Conditions.........................................                  Section 3.2
Data Center Use....................................                    Exhibit B
Dedicated Building Systems.........................                    Exhibit B
Default Rate.......................................                    Exhibit B
Deficiencies.......................................          Section 17.2(a)(ii)
Deficiency.........................................          Section 17.2(a)(ii)
Electrical Capacity................................                    Exhibit B
Event of Default...................................                 Section 16.1
Exculpated Parties.................................              Section 34.1(b)
Existing Rent......................................                 Section 20.2
Expiration Date....................................                    Exhibit B
Extension Notice...................................              Section 30.2(a)
Extension Option...................................                 Section 30.1
Extension Term.....................................                 Section 30.1
Extension Term Commencement Date...................                 Section 30.1
Extension Term Expiration Date.....................                 Section 30.1
Fixed Expiration Date..............................                    Exhibit B
Fixed Rent.........................................                    Exhibit B
FMV................................................                 Section 30.3
free rent..........................................                 Section 32.4
Governmental Authority.............................                    Exhibit B
HVAC...............................................    Exhibit B, Section 9.2(b)
Initial Commencement Date..........................                  Section 1.1
Initial Premises...................................                  Section 1.1
Landlord...........................................                     Preamble
Lease Year.........................................                    Exhibit B
Legal Requirements.................................                    Exhibit B
Lender.............................................                  Section 8.4
Lessor.............................................                    Exhibit B
Managing Agent.....................................                    Exhibit B
Metered Direct Electronic Loads....................                  Section 6.1
Mission Critical Data Center.......................                    Exhibit B
Mortgage...........................................                    Exhibit B
Mortgagee..........................................                    Exhibit B
</TABLE>


                                       iii

<PAGE>

<TABLE>
<S>                                                   <C>
Non-Disturbance Agreement..........................                  Section 8.4
Offer Notice.......................................                 Section 32.1
Offer Space Commencement Date......................                 Section 32.5
Option.............................................                 Section 29.2
Original Tenant....................................                    Exhibit B
PDU................................................                  Section 6.1
Permitted Use......................................                    Exhibit B
Person.............................................                    Exhibit B
Premises...........................................                    Exhibit B
Principal Permitted Use............................                    Exhibit B
Property...........................................                    Exhibit B
Punch List.........................................                  Section 4.2
re-enter...........................................              Section 17.1(b)
re-entered.........................................              Section 17.1(b)
re-entry...........................................              Section 17.1(b)
Remaining Fit Out Items............................                  Section 4.1
Rental Notice......................................              Section 30.4(a)
Response Notice....................................                 Section 29.2
Restoration Estimate...............................                 Section 11.3
Rules and Regulations..............................                    Exhibit B
Scheduled Offer Space Commencement Date............                 Section 32.1
SLA................................................                    Exhibit B
Space 1............................................                  Section 1.1
Space 2............................................                  Section 1.1
Space 3............................................                  Section 1.1
Space 4............................................                  Section 1.1
Substantial Completion.............................                    Exhibit B
Substantially Completed............................                    Exhibit B
Successor Landlord.................................                  Section 8.3
Superior Lease(s)..................................                    Exhibit B
System Efficiency Losses...........................                  Section 6.2
Tenant.............................................       Section 16.3, Preamble
Tenant Alterations.................................                    Exhibit B
Tenant's Notice....................................                 Section 13.2
Tenant's Property..................................                    Exhibit B
Term...............................................                    Exhibit B
Termination Notice.................................                 Section 11.3
Unavoidable Delays.................................                 Section 24.1
Unmetered Direct Electric Loads....................                  Section 6.1
untenantable.......................................                 Section 11.2
Useable Square Feet................................                    Exhibit B
</TABLE>


                                       iv
<PAGE>

Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.

          AGREEMENT OF LEASE, made as of May 8, 2007, between SENTINEL
PROPERTIES - BEDFORD, LLC, a limited liability company with an address c/o
Resolution Capital, LLC, 1270 Avenue of the Americas, Suite 204, New York, New
York 10020 ("Landlord"), and athenahealth, Inc., with an address at 31 Arsenal
street, Watertown, Massachusetts 02472 ("Tenant").

                                   AGREEMENT:

          ALL OF THE CAPITALIZED TERMS NOT DEFINED IN THIS LEASE ARE DEFINED IN
EXHIBIT B ATTACHED HERETO.

ARTICLE 1 DEMISE, PREMISES, TERM, RENT

          SECTION 1.1 Landlord hereby leases to Tenant, and Tenant hereby leases
from Landlord at the Fixed Rent set forth in the definition of Fixed Rent in
Exhibit B:

          (a) the space labeled as the "Initial Premises" on Exhibit A (the
"Initial Premises") for a term to commence on the date of delivery of the
Initial Premises to Tenant pursuant to Section 2.3 (the "Initial Commencement
Date");

          (b) the space labeled as "Space 1" on Exhibit A ("Space 1") for a term
to commence on the later of: (i) the date of delivery of Space 1 to Tenant
pursuant to Section 2.3 or (ii) the date which is * (*) months after the Initial
Commencement Date;

          (c) the space labeled as "Space 2" on Exhibit A ("Space 2") for a term
to commence on the later of: (i) the date of delivery of Space 2 to Tenant
pursuant to Section 2.3 or (ii) the date which is * (*) months after the Initial
Commencement Date;

          (d) the space labeled as "Space 3" on Exhibit A ("Space 3") for a term
to commence on the later of: (1) the date of delivery of Space 3 to Tenant
pursuant to Section 2.3 or (ii) the date which is * (*) months after the Initial
Commencement Date; and

          (e) the space labeled as "Space 4" on Exhibit A ("Space 4") for a term
to commence on the later of: (i) the date of delivery of Space 4 to Tenant
pursuant to Section 2.3 or (ii) the date which is * (*) months after the Initial
Commencement Date.

Notwithstanding the foregoing, Tenant may accelerate the delivery date of one or
more such spaces (but only in their numerical order) by giving Landlord at least
ninety (90) days prior written notice thereof. If Tenant exercises any such
acceleration right then the Fixed Rent shall increase as set forth in the
definition of Fixed Rent in Exhibit B as of the delivery date of such Space to
Tenant pursuant to Section 2.3 rather than as of the later date set forth in the
definition of Fixed Rent. The Term shall end as to the entire Premises on the
Fixed Expiration Date.

          SECTION 1.2 [Intentionally Omitted.]

          SECTION 1.3 Tenant agrees to pay to Landlord the Fixed Rent, without
notice or demand, in lawful money of the United States, in monthly installments
in advance on the first (1st) day of each calendar month during the Term. All
Additional Rent shall be paid within thirty (30) days after billing. All Fixed
Rent and Additional Rent shall be paid at the office of Landlord or such other
place and/or to such other party as Landlord may designate, without any set-off,
offset, abatement or deduction whatsoever except as otherwise expressly provided
in this Lease. Fixed Rent and Additional Rent shall be paid by check drawn on a
Bank which is a member of the Clearing House Association with banking offices in
New York, New York, or Boston, Massachusetts, or at the option of either
Landlord or Tenant, by wire transfer of immediately available funds to an
account designated from time to time by Landlord.

          SECTION 1.4 Notwithstanding anything to the contrary contained in this
Lease, upon execution and delivery of this Lease, Tenant shall pay to Landlord
the sum of $* Dollars representing the first full month's installment of Fixed
Rent for the Initial Premises. Such payment shall be credited by Landlord toward
Tenant's first Fixed Rent obligations as they become due hereunder.

          SECTION 1.5 If any installment or sum of Fixed Rent due hereunder is
not paid on or before the fifth (5th) day of the month during which such
installment is due or any installment of Additional Rent due hereunder is not
paid within thirty (30) days after same is billed, Tenant shall pay Landlord as
Additional Rent: (a) on or before the first (1st) day of the following month,
five percent (5%) of the overdue amount (or such lesser amount as is the maximum
amount permitted by law) in order to defray Landlord's administrative and other
costs in connection with such late payment (which sum Tenant acknowledges is
fair and reasonable and does not constitute interest or a penalty); and (b) if
such amount remains unpaid for thirty (30) days after the date due, interest on
all such Fixed Rent and Additional Rent from the date the same was originally
due (without regard to any grace period) at the Default Rate.

<PAGE>

ARTICLE 2 USE AND OCCUPANCY; TENANT'S EQUIPMENT

          SECTION 2.1 Tenant shall use and occupy the Premises for the Permitted
Use and for no other purpose. Tenant shall not use or occupy or permit the use
or occupancy of any part of the Premises in any manner which is not permitted
hereunder or which would materially and adversely affect (a) the functioning of
the Core Building Systems, (b) the use and occupancy of any part of the Property
by any other tenant or other occupant, or (c) the appearance of the Property or
(d) the proper and economical rendition of any service required to be provided
to Tenant or to any other tenant or occupant of the Building. Tenant shall not
use or permit the Premises to be used for any other use which is not the
Permitted Use or consistent with the use of the Building as a Mission Critical
Data Center as reasonably determined by Landlord.

          SECTION 2.2 At Landlord's option, Landlord may mark the boundaries of
one or more Space(s) by painted lines or by another reasonable method. Tenant
shall not use or occupy any Space(s) unless and until Landlord by written notice
to Tenant delivers possession of such Space(s) to Tenant. If Tenant uses or
occupies all or any part of any such undelivered Space(s) prior to such delivery
then Tenant shall be deemed as of the commencement of any such use or occupancy
to have accelerated the Commencement Date as to such Space(s), to have accepted
such Space(s) in their then "as is" condition and to have agreed to pay the
applicable increase in Fixed Rent for such Space(s).

          SECTION 2.3 Upon Substantial Completion of the Remaining Fit Out Items
pursuant to Article 4, Landlord shall deliver possession of the Premises to
Tenant. Tenant's commencement of any work or Tenant Alterations in the Premises,
moving in of any equipment or personal property or opening for business shall be
deemed to be acceptance of all the Premises. If the Remaining Fit Out Items have
not been Substantially Completed by the date which is sixty (60) days after the
execution and unconditional delivery of this Lease by Landlord and Tenant, then
Tenant may give Landlord a notice of termination and if the remaining Fit Out
Items are not Substantially Completed within ten (10) days after Landlord's
receipt of such notice of termination then Landlord shall within ten (10) days
thereafter refund Tenant's payment if any under Section 1.4 whereupon this Lease
shall terminate and the parties shall have no further obligations hereunder.
Notwithstanding the foregoing, Tenant shall have the right with Landlord's prior
Approval to enter the Premises after the date hereof to perform Data Center
Configuration Work and upon any such entry the Commencement Date shall be deemed
to have occurred; provided, however, that during any such entry Tenant shall not
have the obligation to pay Fixed Rent or Additional Rent and upon any such entry
Tenant shall not be deemed to have accepted any of the Remaining Fit Out Items
that have not been Substantially Completed as of such date. Such Approval shall
not be unreasonably withheld, conditioned or delayed if Landlord in its
reasonable judgment determines that such entry will not materially delay or
increase the cost of performing or completing the Remaining Fit Out Items of any
other work to be performed by Landlord in the Premises. Tenant agrees to perform
such Data Center Configuration Work at times and in a manner reasonably
designated by Landlord and to avoid any interference with Remaining Fit Out
Items in the Premises.

          SECTION 2.4 Subject to the provisions of Articles 3, 4, and 7, and any
other applicable provisions of this Lease, Tenant may install and maintain in
the Premises such equipment as Tenant may reasonably require for the Permitted
Use. If such equipment shall interfere with the normal operation of other
equipment, radio reception or television reception in other parts of the
Building, then and in that event Tenant, at its own cost and expense, shall
either discontinue the use of such equipment in the Premises or cause the same
to be protected and shielded in such a manner as will prevent any disturbance
to, or interference with, any equipment, radios or televisions in other parts of
the Building. To the extent that equipment belonging to other tenants in the
Building materially interferes with Tenant's Permitted Use of the Premises,
Landlord shall employ commercially reasonably efforts to prevent such
interference. All equipment shall be placed and maintained by Tenant in settings
sufficient to absorb and prevent any vibration, noise and annoyance to other
occupants of the Building.

          SECTION 2.5 Tenant shall have a non-exclusive right to use at no
additional charge: (a) the common areas of the Property which are open to the
public, as same exist from time to time, including the driveways, walkways,
entrances, lobbies, parking and loading facilities for any reasonable purpose
subject to the Rules and Regulations, provided, however, that such right shall
not apply to mechanical, electrical and other equipment spaces or any areas that
are not open to the public; and (b) reasonable use of conference rooms and work
station cubicles in the Building available on a first-come, first-served,
reservation basis to the extent of available cubicles subject to the Rules and
Regulations.

ARTICLE 3 ALTERATIONS

          SECTION 3.1 Tenant shall not make any Tenant Alterations without
Landlord's Approval in each instance; provided, however, that Tenant's
installation, modification or removal of wiring, raised flooring, cages,
equipment racks, cable trays and similar ordinary course equipment installation
entirely within the Premises shall not be deemed to be Tenant Alterations
requiring such Approval provided same can be removed without material damage to
the Building (any of the foregoing constituting "Data Center Configuration
Work"). Landlord's Approval of Tenant Alterations may be granted or denied in
Landlord's sole discretion. Landlord shall in no event be required to Approve
the installation outside the Premises by Tenant of any installations or
equipment.


                                       2

<PAGE>

          SECTION 3.2 The following are the conditions (the "Data Center
Configuration Work Approval Conditions") that must be satisfied before any Data
Center Configuration Work may be performed, and as appropriate, during and upon
completion of the performance of any Data Center Configuration Work:

          (a) Tenant shall furnish to Landlord duplicate original policies or
certificates of worker's compensation insurance (covering all persons to be
employed by Tenant and by all contractors and subcontractors supplying materials
or performing work in connection with such Data Center Configuration Work) and
commercial general liability (including property damage coverage) insurance and
during any construction or Alterations by Tenant or its contractors or employees
Builder's Risk coverage (issued on a completed value basis) or an equivalent
coverage reasonably satisfactory to Landlord, all in such form, with such
companies, for such periods and in such amounts as Landlord may reasonably
require, naming Landlord and, any Lessor and any Mortgagee as to which Tenant
has received the name and address as additional insureds for such liability
insurance.

          (b) All Data Center Configuration Work shall be performed by Tenant
(i) at Tenant's sole cost and expense, (ii) in a good and workmanlike manner
using new materials of first class quality, (iii) in compliance with all Legal
Requirements and Rules and Regulations, (iv) subject to Landlord's inspection,
if so requested by Landlord and (v) at hours reasonably Approved by Landlord and
otherwise minimizing unreasonable disturbance to other tenants of the Building.

          (c) Landlord shall Approve, such approval not to be unreasonably
withheld, conditioned or delayed, the general contractors, construction
managers, contractors and subcontractors proposed to be used by Tenant for Data
Center Configuration Work (and if any such party employed by or on behalf of
Tenant causes any labor disharmony anywhere in the Building then Landlord may
require Tenant to immediately discontinue using such party) except that all
mechanical and electrical work shall be performed by contractors who are
designated by Landlord.

          (d) Upon completion of any Data Center Configuration Work, Tenant, at
its expense, shall promptly deliver to Landlord an electronic copy of "as-built"
plans and specifications for such Data Center Configuration Work, in the format
designated by Landlord.

          (e) The indemnity of Landlord by Tenant set forth in Article 28 shall
extend and apply fully as to any costs, damages, liability, etc., arising
directly or indirectly from any Data Center Configuration Work performed by
Tenant.

          SECTION 3.3 If, because of any act or omission of Tenant, its
employees, agents, contractors, or subcontractors, any mechanic's lien, notice
of commencement, notice of intention to lien, U.C.C. financing statement or
other lien, encumbrance, notice, charge or order for the payment of money shall
be filed against Landlord, or against all or any portion of the Premises or the
Property (other than Tenant's Property which under Legal Requirements does not
constitute a fixture), Tenant shall, at its own cost and expense, cause the same
to be discharged of record, by bonding or otherwise, within thirty (30) days
after the filing thereof, and Tenant shall indemnify, defend and save Landlord
harmless against and from all costs, expenses, liabilities, suits, penalties,
claims and demands (including reasonable attorneys' fees and disbursements)
resulting therefrom.

          SECTION 3.4 At Tenant's request, Landlord shall review Tenant's
initial proposed layout of Tenant's equipment racks to be installed in the
Premises based on Tenant's proposed "hot-aisle/cold-aisle" layout and promptly
provide any comments that Landlord has to such proposed layout.

ARTICLE 4 CONDITION OF THE PREMISES; INITIAL WORK

          SECTION 4.1 Tenant has examined the Premises and subject to: (a) the
completion by Landlord and the acceptance by Tenant pursuant to Section 4.2 of
the work described in Exhibit D (the "Remaining Fit Out Items"), and (b) any
Punch List items with respect to the Remaining Fit Out Items to be completed
pursuant to Section 4.2, and (c) any other representations and warranties
expressly made by Landlord hereunder, Tenant hereby accepts possession of the
Premises in their "as is" condition in all respects on the date hereof, subject
to the completion of the Remaining Fit Out Items. Tenant further agrees that,
except for the completion of the Remaining Fit Out Items pursuant to the
Remaining Fit Out Time Line and the completion of any Punch List items with
respect to the Remaining Fit Out Items pursuant to Section 4.2, Landlord shall
have no obligation to perform any work, supply any materials, incur any expenses
or make any installations in order to prepare the Premises for Tenant's
occupancy.

          SECTION 4.2 Within five (5) Business Days after Landlord notifies
Tenant that the Remaining Fit Out Items are Substantially Complete, authorized
representatives of Landlord and Tenant shall jointly inspect the Premises and
prepare a reasonably detailed list of any items of Remaining Fit Out Items that
are not complete (the "Punch List"). After the Commencement Date, Landlord shall
use commercially reasonable and diligent efforts to complete the items on the
Punch List within thirty (30) days after the Commencement Date, subject to
Tenant allowing Landlord and its employees, representatives and contractors
reasonable access to the Premises at all reasonable times after the Commencement
Date to perform same. In the event the items on the Punch List are not completed
on or before the Punch List Completion Date,


                                       3

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.

Tenant as its exclusive remedy may, but shall have no obligation to do so,
complete the Punch List items and deduct such reasonable costs thereof from the
next installment(s) of Fixed Rent until such sums due Tenant have been fully
paid by Landlord or fully credited and accounted for.

ARTICLE 5 REPAIRS AND MAINTENANCE; FLOOR LOAD; SELF-HELP RIGHTS

          SECTION 5.1 (a) Landlord shall diligently maintain and repair to the
extent within Landlord's reasonable control, and otherwise shall use reasonable
efforts to cause the appropriate party to maintain and repair, the Building and
the Core Building Systems in accordance with the SLA in good working order and
condition and to a standard consistent with a Mission Critical Data Center.

          (b) Tenant, at Tenant's expense, shall maintain and repair the
Premises and the fixtures, systems, equipment and appurtenances tin this Lease
to keep same in good order and condition, reasonable wear and tear and damage by
insured casualty excepted, and shall make all nonstructural repairs thereto as
and when needed to preserve them in good working order and condition, except for
reasonable wear and tear, obsolescence and damage for which Tenant is not
responsible pursuant to the provisions of Articles 11 and 12 hereof, provided
that the foregoing shall not be construed to diminish or limit Landlord's
responsibility for its maintenance and repair responsibilities under Section
5.1(a). Notwithstanding the foregoing, all damage or injury to the Premises or
to any other part of the Property, or to its fixtures, equipment and
appurtenances, caused by or resulting from the making of any Alterations by
Tenant, the moving of Tenant's Property, or any carelessness, omission, neglect
or improper conduct of, or Alterations made by Tenant, Tenant's agents,
employees or licensees, shall be repaired at Tenant's expense, (i) by Tenant to
the reasonable satisfaction of Landlord (if the required repairs are
non-structural and do not affect any Core Building System), or (ii) by Landlord
(if the required repairs are structural or affect any Core Building System). All
such repairs shall be of quality or class substantially equal to the original
work or construction to extent possible. If Tenant fails after fifteen (15) days
notice (or such lesser notice as is appropriate in case of emergency or
immediate risk of danger to persons or property) to proceed with due diligence
to make repairs required to be made by Tenant, Landlord may make such repairs at
the expense of Tenant, and Tenant shall pay the reasonable out-of-pocket costs
and expenses thereof paid to third parties by Landlord, with interest at the
Default Rate, as Additional Rent within thirty (30) days after rendition of a
bill or statement therefor.

          SECTION 5.2 Tenant shall not place a live load upon any floor of the
Premises exceeding one hundred fifty (150) pounds per square foot. Tenant shall
not move any safe, heavy batteries or heavy equipment into or out of the
Building without Landlord's reasonable Approval. If items moved into or out of
the Building require special handling, Tenant shall employ only persons holding
a master rigger's license if applicable or any other license required by law to
do such work.

          SECTION 5.3 Landlord shall use commercially reasonable efforts
considering the specific circumstances and the impact of such circumstances on
Tenant's Mission Critical Data Center: (a) to avoid taking any action which
would materially and adversely affect Tenant's use of or business operations
within the Premises, (b) except in an emergency, to provide any of Tenant's
Authorized Contacts with not less than forty-eight (48) hours prior notice
(which may be oral, by a voicemail message or by e-mail) if, notwithstanding
Landlord's commercially reasonable efforts, Landlord must take any action which
would materially and adversely affect Tenant's use of or business operations
within the Premises, (c) to coordinate and cooperate with Tenant to minimize any
cessation or degradation of Tenant's use of or business operations within the
Premises, (d) to take such actions as soon as reasonably practicable to cure or
correct any acts, events or circumstances which materially and adversely affect
Tenant's use of or business operations within the Premises and (e) to operate
the Building in a manner consistent with the operation of a Mission Critical
Data Center. Subject to Landlord's compliance with the provisions of this
Section 5.3 and the provisions of Section 4.2 and Article 11, and except as
otherwise expressly provided in the SLA, there shall be no allowance to Tenant
for a diminution of rental value, no constructive eviction of Tenant and no
liability on the part of Landlord by reason of inconvenience, annoyance or
injury to business arising from Landlord making, or failing to make, any
repairs, alterations, additions or Improvements in or to any portion of the
Property or the Premises, or in or to fixtures, appurtenances or equipment
thereof.

ARTICLE 6 UTILITY EXPENSES

          SECTION 6.1

                                       *

                                       4

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.

          *


          SECTION 6.2 *

          SECTION 6.3 *

          SECTION 6.4 *

          SECTION 6.5 *

          SECTION 6.6 Any delay or failure of Landlord in computing or billing
for the rent adjustment in this Leaseabove provided shall not constitute a
waiver of or in any way impair the continuing obligation of Tenant to pay such
rent adjustment hereunder. Notwithstanding any termination of this Lease prior
to the Expiration Date, Tenant's obligation to pay Additional Rent under this
Article shall continue and shall cover all periods up to the Expiration Date and
shall survive any expiration or termination of this Lease.

ARTICLE 7 LEGAL REQUIREMENTS

          SECTION 7.1 Tenant, at its sole expense, shall comply with all Legal
Requirements applicable to the Premises, or the use and occupancy thereof by
Tenant, and make all repairs or Alterations required thereby, whether structural
or nonstructural, ordinary or extraordinary, except for those repairs and
Alterations that are Landlord's obligation hereunder or unless otherwise
expressly provided in this Lease; provided, however, that Tenant shall not be
obligated to comply with any Legal Requirement applicable to the Property
(exclusive of the Premises) or requiring any structural alteration to the
Premises unless the application of such Legal Requirement arises from (a)
Tenant's particular manner of use or occupancy of the Premises (as distinguished
from the use or occupancy of the Premises for office or data center purposes
generally), (b) any cause or condition created by or on behalf of Tenant or any
of its Affiliates (including any Alterations), (c) the breach of any of Tenant's
obligations under this Lease, or (d) any hazardous materials having been brought
into the Building by Tenant or any of its Affiliates. Tenant shall not do or
permit to be done any act or thing upon the Premises which will invalidate or be
in conflict with customary requirements of Landlord's insurance policies or any
provisions of any of Landlord's insurance policies of which Landlord has
notified Tenant, and shall not do or permit anything to be done in or upon the
Premises, or use the Premises in a manner, or bring or keep anything in this
Lease, which shall increase the rates for casualty or liability insurance
applicable to Building or the Property. The foregoing notwithstanding, to the
extent that modifications to the Building or the land on which the Building is
located are required in order to bring same into compliance with any of the
Legal Requirements in effect from and after the date hereof, Landlord shall be
responsible for the compliance of such item(s) with the Legal Requirements at
Landlord's sole cost and expense; provided, however, all such costs shall be
paid by Tenant to the extent that any such required modifications are the result
of: (i) leasehold improvements made by (or at the request of) Tenant, including
without limitation, Alterations, (ii) any particular use made of the Premises by
Tenant which is not in the


                                       5

<PAGE>

nature of a Principal Permitted Use, or (iii) any other negligent or willful act
or omission of Tenant or its agents or employees.

          SECTION 7.2 Landlord shall keep and maintain the common areas of the
Property serving the Premises (including, without limitation, the parking areas
serving the Premises), all in compliance with the American with Disabilities Act
and all other applicable Legal Requirements to the extent that any
non-compliance with Legal Requirements would have a material adverse effect on
Tenant's use of the Premises as a Mission Critical Data Center.

ARTICLE 8 MORTGAGES; SUBORDINATION; ESTOPPEL CERTIFICATES

          SECTION 8.1 Subject to the provisions of Section 8.4, all rights of
Tenant under this Lease are and shall be subject and subordinate in all respects
to all existing and future Mortgages and all existing and future Superior Leases
(there being no Superior Leases on the date hereof), and all other easements,
restrictions, agreements, declarations and interests now or hereafter of record
and Tenant shall not cause Landlord to be in default under any of the foregoing.
This Section 8.1 shall be self-operative and no further instrument of
subordination shall be required. In confirmation of such subordination, Tenant
shall execute, acknowledge and deliver within ten (10) days after request any
reasonable and customary instrument that Landlord or any Lessor or Mortgagee may
reasonably request to evidence such subordination.

          SECTION 8.2 In the event of any act or omission of Landlord which
would give Tenant the right, immediately or after lapse of a period of time, to
cancel or terminate this Lease, or to claim a partial or total eviction, Tenant
shall not exercise such right (a) until it has given written notice of such act
or omission to each Mortgagee and Lessor whose name and address shall previously
have been furnished to Tenant in writing, and (b) unless such act or omission
shall be one which is not capable of being remedied by Landlord or such
Mortgagee or Lessor within a reasonable period of time, until a reasonable
period for remedying such act or omission shall have elapsed following the later
to occur of (i) the giving of such notice or (ii) the time when such Mortgagee
or Lessor shall have become entitled under such Mortgage or Superior Lease, as
the case may be, to remedy the same (which reasonable period shall, in the case
of this clause (iii), in no event be (A) less than the period to which Landlord
would be entitled under this Lease, after similar notice, to effect such remedy
nor (B) more than the period to which Landlord would be entitled under this
Lease, after similar notice, to effect such remedy, plus thirty (30) days, and
which period shall only commence on the date such Mortgagee obtains possession
and control of the mortgaged property). If more than one Mortgagee or Superior
Lessor shall become entitled to any additional cure period under this Section
8.2, such cure periods shall run concurrently, not consecutively.

          SECTION 8.3 If a Mortgagee or Lessor shall succeed to the rights of
Landlord under this Lease, whether through possession or foreclosure action or
delivery of a new lease or deed, then at the request of such party so succeeding
to Landlord's rights ("Successor Landlord") and upon Successor Landlord's
written agreement to accept Tenant's attornment, Tenant shall attorn to and
recognize Successor Landlord as Tenant's landlord under this Lease, and shall
promptly execute, acknowledge and deliver any customary instrument reasonably
acceptable to Tenant that Successor Landlord may reasonably request to evidence
such attornment. Upon such attornment this Lease shall continue in full force
and effect as, or as if it were, a direct lease between Successor Landlord and
Tenant upon all of the terms, conditions and covenants as are set forth in this
Lease and shall be applicable after such attornment except that Successor
Landlord shall not: (a) be liable for any previous act or omission of Landlord
under this Lease, except to the extent same continues after such attornment; (b)
be subject to any offset, not expressly provided for in this Lease or the SLA,
which shall have theretofore accrued to Tenant against Landlord; or (c) be bound
by any previous modification of this Lease, not expressly provided for in this
Lease, or by any previous prepayment of more than one month's Fixed Rent, unless
such modification or prepayment shall have been expressly Approved by such
Mortgagee or Lessor; provided that the name and address of such Mortgagee or
Lessor have been provided to Tenant in writing.

          SECTION 8.4 Notwithstanding the foregoing provisions of this Article
8, as a condition to Tenant's agreement hereunder to subordinate Tenant's
interest in this Lease to (a) any Mortgage encumbering all or any part of the
Property on the Commencement Date and (b) any future Mortgages encumbering all
or any part of the Property, Landlord shall obtain from each current Mortgagee
and shall obtain (but at Tenant's sole cost and expense) from each future
Mortgagee an agreement, in the standard form then-customarily employed by such
Mortgagee (or, if none, any form selected by Landlord, satisfactory to such
Mortgagee, and reasonably satisfactory to Tenant), with such modifications
thereto as are reasonably requested by Tenant and are reasonably acceptable to
Landlord and such Mortgagee, pursuant to which such Mortgagee shall agree that
if and so long as no Event of Default hereunder shall have occurred and be
continuing, the leasehold estate granted to Tenant and all of the rights of
Tenant pursuant to this Lease shall not be terminated, modified, affected or
disturbed by any action which such Mortgagee may take to foreclose any such
Mortgage, and that any Successor Landlord shall recognize this Lease as being in
full force and effect as if it were a direct lease between such Successor
Landlord and Tenant upon all of the terms, covenants, conditions and options
granted to Tenant under this Lease, except as otherwise provided in Section 8.3
hereof (any such agreement, a "Non-Disturbance Agreement"). The form of Non
Disturbance Agreement utilized by the existing mortgagee of the Building (the
"Lender") is attached to this Lease as Exhibit E. Provided that Tenant executes
such


                                       6

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


form simultaneously with its execution and delivery of this Lease, Landlord
agrees to cause the same to be executed by Lender within ten (10) Business Days
after execution and delivery of this Lease.

          SECTION 8.5 Tenant agrees, at any time and from time to time, as
requested by Landlord, upon not less than ten (10) days' prior notice, to
execute, acknowledge and deliver an estoppel certificate or a statement as to
any matters reasonably requested by Landlord with respect to this Lease and the
Premises. The parties acknowledge that any statement delivered pursuant to this
Section 8.5 may be relied upon by others, including any purchaser or owner of
all or any part of the Property, or by any existing or potential Mortgagee or
Lessor.

          SECTION 8.6 Tenant covenants and agrees not to execute any security
agreements, Uniform Commercial Code Financing Statements, chattel mortgages,
conditional bills of sale, leases or other title retention agreements or any
modifications, extensions, replacement or amendments thereto in connection with
the purchase of, or covering or affecting any fixtures, equipment or personal
property used at the Premises, except to the extent the same relate only to
Tenant's Property which does not constitute a fixture or part of the Building
under the law of the Commonwealth of Massachusetts.

ARTICLE 9 SERVICES

          SECTION 9.1 Service Level Agreement. Landlord shall provide or cause
to be provided the services set forth in the SLA.

          SECTION 9.2 Tenant's Use of Core Building Systems. The following
requirements apply to Tenant's use of the Core Building Systems described below:


                                       *


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<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.

                                        *

          SECTION 9.3 Tenant to Manage Certain Equipment. Tenant shall have the
sole obligation, at its cost and expense, to manage, maintain, monitor and
repair (or contract with a third party for the management, maintenance,
monitoring and repair of) any facility or equipment installed by or on behalf of
Tenant in the Premises (other than the Remaining Fit Out Items) and Landlord
shall have no obligations with respect to same.

          SECTION 9.4 No Warranty of Landlord. Except as expressly set forth in
the SLA, Landlord does not warrant that any of the services to be provided by
Landlord under this Lease, including without limitation the Core Building
Systems and any services referenced in the SLA: (a) will be adequate for
Tenant's particular purposes or as to any other particular need of Tenant or (b)
will be free from interruption, and Tenant acknowledges that any one or more
such services may be interrupted or suspended by reason of Unavoidable Delays.
In addition, Tenant acknowledges that Landlord has the right to stop, interrupt
or reduce service of the Core Building Systems and any services referenced in
the SLA by reason of Unavoidable Delays, or for repairs, additions, alterations,
replacements, or improvements which are appropriate or necessary to be made or
for any other reasonable purpose; provided that Landlord shall comply with
Sections 5.1(a) and 5.3 and, provided, further, that Landlord shall use
reasonable efforts to avoid or minimize interruption to services of Core
Building Systems necessary for the provisioning of critical power and cooling to
the Premises. Any such interruption or discontinuance of service, or the
exercise of such right by Landlord to suspend or interrupt such service, shall
not (i) constitute an actual or constructive eviction or disturbance of Tenant's
use and possession of the Premises, in whole or in part, (ii) entitle Tenant to
any compensation or to any abatement or diminution of Fixed Rent or Additional
Rent (except as expressly set forth in the SLA), (iii) relieve Tenant from any
of its obligations under this Lease, or (iv) impose any responsibility or
liability upon Landlord or its agents by reason of inconvenience or annoyance to
Tenant, or injury to or interruption of Tenant's business, or otherwise.
Landlord shall use reasonable efforts to minimize interference with Tenant's
access to and use and occupancy of the Premises in making any repairs,
alterations, additions, replacements, decorations or improvements. Landlord
shall not be required to furnish any services except as expressly provided in
this Article 9 or in the SLA.

ARTICLE 10 INSURANCE

          SECTION 10.1 Tenant, at its expense, shall obtain and keep in full
force and effect a policy of commercial general liability insurance with respect
to the Premises under which Tenant is named as the insured and Landlord, the
Managing Agent, and any Lessors and any Mortgagees (whose names shall have been
furnished to Tenant) are named as additional insureds, which insurance shall
provide primary coverage for the Premises without contribution from any other
insurance carried by or for the benefit of Landlord, the Managing Agent, or any
Lessors or Mortgagees named as additional insureds. Tenant's primary commercial
general liability policy shall contain a provision that the policy shall be
noncancellable unless thirty (30) days' written notice shall have been given to
Landlord and Landlord shall similarly receive thirty (30) days' notice of any
material change in coverage. The minimum limits of liability shall be a combined
single limit with respect to each occurrence in an amount of not less than
* per location general aggregate limit (including umbrella coverage);
provided, however, that Landlord shall retain the right to require Tenant to
increase said coverage to that amount of insurance which in Landlord's
reasonable judgment is then being customarily required by prudent landlords of
comparable buildings in the metropolitan area in which the Building is located
and provided further that Landlord shall require similar increases of other
tenants of space in the Building comparable to the Premises to the extent
Landlord shall then have the right to do so under applicable leases. Tenant
shall also obtain and keep in full force and effect during the Term, (a)
insurance against loss or damage by fire, and such other risks and hazards as
are insurable under then available standard forms of commercial property
insurance - special causes of loss form insurance policies with extended
coverage, to Tenant's Property and Tenant Alterations with respect to the
Premises for the full insurable value thereof or on a replacement cost basis,
(b) Workers' Compensation Insurance, as required by Legal Requirements, (c)
Disability Benefits Law Policy, if required by Legal Requirements, and (d) such
other insurance in such amounts as Landlord, any Mortgagee or Lessor may
reasonably require from time to time from a majority of the tenants in the
Building. All insurance required to be carried by Tenant pursuant to the terms
of this Lease shall be effected under valid and enforceable policies issued by
reputable and independent insurers permitted to do business in the Commonwealth
of Massachusetts, and rated in Best's Insurance Guide, or any successor thereto
or if there be none, an organization having a national reputation) as having a
Best's Financial Strength Rating of "A" and a "Financial Size Category" of at
least "XII" or if such ratings are not then in effect, the equivalent thereof.


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<PAGE>

          SECTION 10.2 (a) The parties hereto do hereby waive, any and all
rights of recovery against the other, or against the officers, employees,
partners, agents and representatives of the other, for loss of or damage to the
property of the waiving party to the extent such loss or damage is insured
against under any insurance policy that Landlord or Tenant is obligated to carry
pursuant to this Article 10. In addition, the parties hereto shall procure an
appropriate clause in, or endorsement on, any fire or extended coverage
insurance covering the Premises, the Building and personal property, fixtures
and equipment located thereon or tin this Lease, pursuant to which the insurance
companies waive subrogation or consent to a waiver of recovery and subject to
obtaining such clauses or endorsements of waiver of subrogation or consent to a
waiver of right of recovery, hereby agree not to make any claim against or seek
to recover from the other for any loss or damage to its property or the property
of others resulting from fire or other hazards covered by such fire and extended
coverage insurance; provided, however, that the release, discharge, exoneration
and covenant not to sue in this Lease contained shall be limited by and
coextensive with the terms and provisions of the waiver of subrogation clause or
endorsements or clauses or endorsements consenting to a waiver of right of
recovery. If the payment of an additional premium is required for the inclusion
of such waiver of subrogation or consent to waiver provision, each party shall
advise the other of the amount of any such additional premiums and the other
party at its own election may, but shall not be obligated to, pay the same. If
such other party shall not elect to pay such additional premium, the first party
shall not be required to obtain such waiver of subrogation or consent to waiver
provision. Tenant acknowledges that Landlord shall not carry insurance on Tenant
Alterations (if any) or Tenant's Property and that Landlord shall not carry
insurance against interruption of Tenant's business.

          (b) As to each party hereto, provided such party's right of full
recovery under the applicable insurance policy is not adversely affected, such
party hereby releases the other (its servants, agents, contractors, employees
and invitees) with respect to any claim (including a claim for negligence) which
it might otherwise have against the other party for loss, damages or destruction
of the type covered by such insurance with respect to its property by fire or
other casualty, i.e., in the case of Landlord, as to the Building, and, in the
case of Tenant, as to Tenant's Property and Tenant Alterations (including rental
value or business interruption, as the case may be) occurring during the Term of
this Lease.

          SECTION 10.3 On or prior to the Commencement Date, Tenant shall
deliver to Landlord appropriate evidence reasonably satisfactory to Landlord
(which evidence may be Acord Form 27 Evidence of Property Insurance as to
property insurance and Acord Form 75 Insurance Binder as to other coverages or
the substantially equivalent forms but shall not include Acord Form 25
Certificate of Insurance) confirming the existence of the insurance required to
be carried by Tenant pursuant to this Article 10, including evidence of waivers
of subrogation required pursuant to Section 10.2. Evidence of each renewal or
replacement of a policy shall be delivered by Tenant to Landlord at least twenty
(20) days prior to the expiration of such policy.

ARTICLE 11 DESTRUCTION OF THE PROPERTY; LOSS OR DAMAGE

          SECTION 11.1 If the Premises shall be damaged by fire or other
casualty, or if the Building shall be so damaged that Tenant shall be deprived
of reasonable access to the Premises (whether or not the Premises are damaged),
Tenant shall give prompt notice thereof to Landlord, and the damage (a) to the
Premises (including, without limitation, the Remaining Fit Out Items) but
excluding Tenant Alterations (the "Base Building Restoration"), shall be
repaired by and at the expense of Landlord or by Landlord using reasonable
efforts to cause the party legally responsible for such restoration to do so, as
appropriate, (the "Base Building Restoration"), and (b) by Tenant as to all
Tenant Alterations, Data Center Configuration Work and Tenant's Property. Until
the date on which Landlord delivers possession of the Premises as the case may
be, to Tenant with the Base Building Restoration Substantially Completed, Fixed
Rent and Additional Rent shall be reduced in the proportion which the Useable
Square Feet of the part of the Premises which is neither usable nor used by
Tenant bears to the total Useable Square Feet of the Premises. Landlord shall
have no obligation to repair any damage to, or to replace, any of the Tenant
Alterations or Tenant's Property.

          SECTION 11.2 Anything contained in Section 11.1 to the contrary
notwithstanding, if the Premises are damaged in their entirety or are rendered
untenantable, and if Landlord shall decide not to restore the Premises, or if
the Building shall be so damaged by fire or other casualty that, in Landlord's
opinion, substantial alteration, demolition, or reconstruction of the Building
shall be required (whether or not the Premises shall have been damaged or
rendered untenantable), then in any of such events, Landlord may, not later than
sixty (60) days following the date of the damage, give Tenant a notice in
writing terminating this Lease. If this Lease is so terminated, the Term shall
expire upon the tenth (10th) day after such notice is given, and Tenant shall
vacate the Premises and surrender the same to Landlord. Upon the termination of
this Lease under the conditions provided for in this Section 11.2, Tenant's
liability for Fixed Rent and Additional Rent shall cease as of the date of such
fire or other casualty, and any prepaid portion of Fixed Rent or Additional Rent
for any period after such date shall be refunded by Landlord to Tenant. As used
in this Lease, the Premises shall be deemed "untenantable" in the event that a
portion of the Premises shall have been damaged to the extent that Tenant is
unable to reasonably conduct its business in the undamaged portion of the
Premises.


                                       9

<PAGE>

          SECTION 11.3 If the Premises are damaged by fire or other casualty and
are rendered untenantable thereby, or if the Building or Core Building Systems
shall be so damaged that Tenant shall be deprived of reasonable access to or use
of the Premises sufficient, in Tenant's reasonable judgment, for the normal
conduct of Tenant's business operations in the Premises, and Tenant has given
timely notice thereof to Landlord pursuant to Section 11.1, then Landlord shall,
within thirty (30) days following the date of the damage, deliver to Tenant an
estimate prepared by a contractor or architect selected by Landlord (the
"Restoration Estimate") of the date by which such contractor or architect
believes the Base Building Restoration shall be Substantially Completed. If the
Restoration Estimate shall indicate that the Base Building Restoration shall not
be Substantially Completed on or before the date which shall be six (6) months
following the date of such damage or destruction, then either Landlord or Tenant
shall have the right to terminate this Lease by giving written notice (the
"Termination Notice") to other not later than thirty (30) days following receipt
of the Restoration Estimate. If either party shall timely deliver a Termination
Notice, then this Lease shall be deemed canceled and terminated as of the date
of the giving of the Termination Notice as if such date were the Expiration
Date, and Fixed Rent and Additional Rent shall be apportioned and shall be paid
or refunded, as the case may be up to and including the date of such
termination.

          SECTION 11.4 Anything contained in this Article 11 to the contrary
notwithstanding, in the event of a catastrophic casualty event such that it is
impossible in Tenant's reasonable determination for the Base Building
Restoration to be completed within six (6) months, then Tenant may immediately
vacate the Premises, surrender same to Landlord in the condition required by
this Lease and terminate this Lease. Upon the termination of this Lease under
the conditions provided for in this Section 11.4, Tenant's liability for Fixed
Rent and Additional Rent shall cease as of the date of such casualty, and any
prepaid portion of Fixed Rent or Additional Rent for any period after such date
shall be refunded by Landlord to Tenant.

          SECTION 11.5 Subject to any applicable Legal Requirements which shall
supersede the provisions of this Article 11, this Article 11 constitutes an
express agreement governing any case of damage or destruction of the Premises or
the Building by fire or other casualty, and any applicable law which provides
for such contingency in the absence of an express agreement now or hereafter in
force shall have no application in any such case.

ARTICLE 12 EMINENT DOMAIN

          SECTION 12.1 If (a) all of the floor area of the Premises or so much
thereof as shall render the Premises untenantable or, in Tenant's reasonable
judgment, unsuitable for the conduct of Tenant's business as such business was
being conducted immediately prior thereto, shall be acquired or condemned for
any public or quasi-public use or purpose, or (b) a portion of the Property, not
including the Premises, shall be so acquired or condemned, but by reason of such
acquisition or condemnation, Tenant no longer has means of access to the
Premises, then this Lease and the Term shall end as of the date of the vesting
of title with the same effect as if that date were the Expiration Date. In the
event of any termination of this Lease and the Term pursuant to the provisions
of this Article 12, Fixed Rent and Additional Rent shall be apportioned as of
the date of sooner termination and any prepaid portion of Fixed Rent or
Additional Rent for any period after such date shall be refunded by Landlord to
Tenant.

          SECTION 12.2 In the event of any such acquisition or condemnation of
all or any part of the Property, Landlord shall be entitled to receive the
entire award for any such acquisition or condemnation. Tenant shall have no
claim against Landlord or the condemning authority for the value of any
unexpired portion of the Term or Tenant Alterations, and Tenant hereby expressly
assigns to Landlord all of its right in and to any such award. Nothing contained
in this Section 12.2 shall be deemed to prevent Tenant from making a separate
claim in any condemnation proceedings for the then value of any Tenant's
Property included in such taking and for any moving expenses, provided such
award shall be made by the condemning authority in addition to, and shall not
result in a reduction of, the award made by it to Landlord.

          SECTION 12.3 If only a part of the Property shall be so acquired or
condemned and the remaining portion thereof is reasonably feasible (in the
reasonable opinion of Tenant) to permit the Tenant to continue its operation as
a Mission Critical Data Center, then, subject to Section 12.1, this Lease and
the Term shall continue in force and effect. If a part of the Premises shall be
so acquired or condemned and this Lease and the Term shall not be terminated,
Landlord, at Landlord's expense, shall restore that part of the Premises not so
acquired or condemned so as to constitute tenantable Premises. From and after
the date of the vesting of title, Fixed Rent and Additional Rent shall be
reduced in the proportion which the area of the part of the Premises so acquired
or condemned bears to the total area of the Premises immediately prior to such
acquisition or condemnation.

ARTICLE 13 ASSIGNMENT AND SUBLETTING

          SECTION 13.1 Except as otherwise expressly provided in this Lease,
Tenant, for itself, its heirs, distributees, executors, administrators, legal
representatives, successors and assigns, expressly covenants that it shall not
assign, mortgage, pledge, encumber, or otherwise transfer this Lease, nor sublet
(nor modify, amend or extend a sublease), nor suffer, nor permit the Premises,
or any part thereof to be used or occupied by others without the Approval of
Landlord in each instance.


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<PAGE>

In no event shall any permitted subtenant assign or encumber its sublease or
further sublet all or any portion of its sublet space, or otherwise suffer or
permit the sublet space or any part thereof to be used or occupied by others,
without Landlord's Approval in each instance. Any assignment, sublease,
mortgage, pledge, encumbrance or transfer in contravention of the provisions of
this Article 13 shall be void.

          SECTION 13.2 If Tenant shall, at any time or from time to time, during
the Term desire to assign this Lease or sublet all or part of the Premises,
Tenant shall give notice (a "Tenant's Notice") thereof to Landlord, which
Tenant's Notice shall set forth: (a) with respect to an assignment of this
Lease, the date Tenant desires the assignment to be effective and any
consideration Tenant would receive under such assignment, (b) with respect to a
sublet of all or a part of the Premises (i) the dates upon which Tenant desires
the sublease term to commence and expire, (ii) the rental rate and other
material business terms upon which Tenant would sublet such premises, and (iii)
a description of the Premises showing the portion to be sublet, the effective or
commencement date of which shall be not less than thirty (30) nor more than one
hundred and eighty (180) days after the giving of such notice, (c) a statement
setting forth in reasonable detail the identity of the proposed assignee or
subtenant, the nature of its business and its proposed use of the Premises, (d)
current financial information with respect to the proposed assignee or
subtenant, including its most recent financial report, (e) a true and complete
copy of the proposed assignment or sublease and any other agreements relating
thereto, and (f) an agreement by Tenant to indemnify Landlord against liability
resulting from any claims that may be made against Landlord by the proposed
assignee or subtenant or by any brokers or other Persons claiming a commission
or similar compensation in connection with the proposed assignment or sublease.
Tenant's Notice shall be deemed an offer from Tenant to Landlord whereby
Landlord (or Landlord's designee) may, at its option (except in the case of an
assignment or sublease pursuant to Section 13.9): (A) terminate this Lease as to
the entire Premises in the event of a proposed assignment or a proposal sublease
of all or substantially all of the Premises; or (B) terminate this Lease only as
to the relevant portion(s) of the Premises in the event of a sublease of less
than all or substantially all of the Premises but only if such sublease is for
all or substantially all of the remaining Term of this Lease (including any
Extension Option but only if Tenant has irrevocably exercised such Extension
Option). Either such option may be exercised by Landlord by notice given to
Tenant at any time within thirty (30) days after Tenant's Notice has been given
by Tenant to Landlord, and during such thirty (30) day period, Tenant shall not
assign this Lease nor sublet such space to any Person other than Landlord.

          SECTION 13.3 If Landlord exercises its option to terminate this Lease
with respect to all or a portion of the Premises pursuant to Section 13.2
hereof, then this Lease shall end and expire (or be modified to reduce the size
of the Premises) on the date that such assignment or sublease was to be
effective or commence, as the case may be, and the Fixed Rent and Additional
Rent due hereunder shall be paid and apportioned to such date. In such event,
Landlord and Tenant, upon request of either party, shall enter into an amendment
of this Lease ratifying and confirming such total or partial termination, and
setting forth appropriate modifications, if any, to the terms and provisions
hereof. Following such termination, Landlord shall be free to and shall have no
liability to Tenant if Landlord should lease the Premises (or any part thereof)
to Tenant's prospective assignee or subtenant.

          SECTION 13.4 In the event Landlord does not exercise the option
provided to it pursuant to Section 13.2 hereof, and provided that no Event of
Default shall have occurred and be continuing under this Lease as of the time
Landlord's Approval is requested by Tenant, Landlord's Approval to the proposed
assignment or sublease shall not be unreasonably withheld and shall be given or
denied during the thirty (30) day period under Section 13.2; provided, however,
that:

          (a) Tenant shall have complied with the provisions of Section 13.2
hereof and Landlord shall not have exercised any of its options thereunder
within the time permitted therefore;

          (b) Tenant shall have furnished Landlord with the name and address of
the proposed assignee or subtenant and its principals, financial statements for
the proposed assignee or subtenant and proof satisfactory to Landlord evidencing
that the proposed assignee or subtenant is experienced in and will secure
personnel reasonably experienced in the data center business being conducted at
the demised premises as permitted under the terms of this lease;

          (c) in Landlord's reasonable judgment, the proposed assignee or
subtenant is engaged in a business or activity, and the Premises, or the
relevant part thereof, will be used in a manner, which does not violate the
restrictions set forth in Article 2 hereof;

          (d) in Landlord's reasonable discretion, the proposed assignee or
subtenant and its proposed use of the Premises is consistent with the use of the
Premises as a Mission Critical Data Center and will not adversely affect
security or operation of the Building;

          (e) the proposed assignee or subtenant: (i) is of sufficient financial
worth considering the responsibility involved (which shall include that it then
has at least a credit profile by the major credit reporting agencies such as
Moody's, Standard & Poor and Dun & Bradstreet at least equal to that of Original
Tenant on the date of this Lease), and Landlord has been furnished with
reasonable evidence thereof; and (ii) the proposed subtenant and its proposed
use of the Premises will not require greater services from Landlord and will not
increase the cost of operating the Building.


                                       11

<PAGE>

          (f) in the event Landlord has space in the Building which is or after
renovation would be reasonably comparable and available for lease, then (i)
neither the proposed assignee or subtenant nor any of its Affiliates is then an
occupant of any part of the Building, and (ii) the proposed assignee or
subtenant is not a Person (or Affiliate of a Person) with whom Landlord or
Landlord's agent is then, or has been within the previous six (6) month period,
engaging in bona fide negotiations (as evidenced by a tour of the Building, a
draft lease, a term sheet or a letter of intent) in connection with rental of
space in the Building;

          (g) the form of the proposed sublease or assignment and assumption
agreement and all related documents shall be reasonably satisfactory to Landlord
and shall comply with the applicable provisions of this Article 13, and Tenant
shall deliver a true and complete original, fully executed counterpart of such
sublease or assignment and all related documents to Landlord promptly upon the
execution and delivery thereof;

          (h) Tenant and its proposed subtenant or assignee, as the case may be,
and any guarantor of this Lease or such sublease shall execute and deliver to
Landlord an agreement, in form and substance satisfactory to Landlord, setting
forth the terms and conditions upon which Landlord shall have granted its
Approval to such assignment or subletting (provided such terms and conditions
are consistent with the terms and conditions of this Article 13), and the
agreement of Tenant and such subtenant or assignee, as the case may be, to be
bound by the provisions of this Article 13;

          (i) there shall not be more than three (3) occupants of the Premises
(considering Tenant and its Affiliates which are not separately demised as one
occupant);

          (j) the amount of the aggregate rent to be paid by the proposed
subtenant shall not be less than the then current fair market rent for the
Useable Square Feet in the Premises, determined as though the Premises were
vacant (and taking into account all relevant facts regarding the Premises and
the rights to be afforded to the assignee or subtenant), and the rental and
other terms and conditions of the sublease shall be substantially the same as
those contained in Tenant's Notice;

          (k) Tenant shall reimburse Landlord, as Additional Rent upon demand,
for (A) the reasonable out-of-pocket costs and expenses incurred by Landlord in
connection with the assignment or sublease, including the costs of making
investigations as to the acceptability of the proposed assignee or subtenant and
the cost of reviewing plans and specifications proposed to be made in connection
therewith, and (B) Landlord's reasonable legal fees and disbursements incurred
in connection with the granting of any requested Approval and the preparation of
Landlord's Approval to the sublease or assignment;

          (l) Tenant shall not have (i) advertised or publicized in any way the
availability of the Premises without Landlord's Approval, or (ii) listed the
Premises for sublease or assignment with a broker, agent or otherwise at a
rental rate less than the Fixed Rent and Additional Rent at which Landlord is
then offering to lease comparable space in the Building which is or after
renovation could be reasonably comparable and available for lease;

          (m) the proposed occupancy shall not impose a materially increased
burden upon services to be supplied by Landlord to Tenant, unless Tenant and
such proposed subtenant or assignee shall agree with Landlord in writing to pay
the costs of such additional services; and

          (n) the proposed subtenant or assignee shall not be entitled, directly
or indirectly, to diplomatic or sovereign immunity and shall be subject to the
service of process in, and the jurisdiction of the courts of the Commonwealth of
Massachusetts.

Each sublease pursuant to this Section 13.4 shall be subject to all of the
covenants, agreements, terms, provisions and conditions contained in this Lease.
If Landlord shall decline to give its Approval to any proposed assignment or
sublease, or if Landlord shall exercise its option under Section 13.2 hereof,
Tenant shall indemnify, defend and hold harmless Landlord against and from any
and all losses, liabilities, damages, costs and expenses (including reasonable
attorneys' fees and disbursements) resulting from any claims that may be made
against Landlord by the proposed assignee or subtenant arising from or in
connection with such proposed assignment or sublease, or by any brokers or other
Persons (with whom Tenant or its proposed assignee or subtenant may have dealt)
claiming a commission or similar compensation in connection with the proposed
assignment or sublease.

          SECTION 13.5 When requesting Landlord's consent, Tenant shall supply
all such information as may reasonably be required for Landlord to review the
business reputation and financial condition of the proposed Transferee.

          SECTION 13.6 In the event that (a) Landlord fails to exercise its
option under Section 13.2 hereof and Approves a proposed assignment or sublease,
and (b) Tenant fails to execute and deliver the assignment or sublease which
Landlord Approved within one hundred eighty (180) days after the giving of such
Approval, then, Tenant shall again comply with all of the provisions and
conditions of Section 13.2 hereof before assigning this Lease or subletting all
or part of the Premises.

          SECTION 13.7 With respect to each and every sublease authorized by
Landlord under the provisions of this Lease, it is further agreed that: (a) no
sublease shall be for a term ending later than one (1) day prior to the
Expiration Date of


                                       12

<PAGE>

this Lease (as the same may be extended); (b) no sublease shall be delivered,
and no subtenant shall take possession of the Premises or any part thereof,
until an executed counterpart of such sublease has been delivered to Landlord
and Approved by Landlord; and (c) each sublease shall be subject and subordinate
to this Lease and to the matters to which this Lease is or shall be subordinate,
and each subtenant by entering into a sublease is deemed to have agreed that in
the event of termination, re-entry or dispossession by Landlord under this
Lease, Landlord may, at its option, take over all of the right, title and
interest of Tenant, as sublandlord, under such sublease, and such subtenant
shall, at Landlord's option, attorn to Landlord pursuant to the then executory
provisions of such sublease, except that Landlord shall not be (i) liable for
any previous act or omission of Tenant under such sublease, (ii) subject to any
counterclaim, offset or defense, not expressly provided in such sublease, which
theretofore accrued to such subtenant against Tenant, (iii) bound by any
previous modification of such sublease or by any previous prepayment of more
than one month's Fixed Rent or of any Additional Rent unless previously Approved
by Landlord, or (iv) obligated to perform any work in the subleased space or to
prepare it for occupancy; and in connection with such attornment, the subtenant
shall execute and deliver to Landlord any instruments Landlord may reasonably
request to evidence and confirm such attornment. Each subtenant or licensee of
Tenant shall be deemed, automatically upon and as a condition of its occupying
or using the Premises or any part thereof, to have agreed to be bound by the
terms and conditions set forth in this Article 13. The provisions of this
Article 13 shall be self-operative and no further instrument shall be required
to give effect to this provision.

          SECTION 13.8 If Landlord shall Approve any assignment of this Lease or
any sublease (other than an assignment or sublease pursuant to Section 13.9
hereof), or if Tenant shall enter into any other assignment or sublease
permitted hereunder, Tenant shall, in consideration therefor, pay to Landlord,
as Additional Rent:

          (a) in the case of an assignment, on the effective date of the
assignment, an amount equal to fifty percent (50%) of (i) all sums and other
consideration paid to Tenant by the assignee for or by reason of such assignment
(including sums paid for Tenant's Property, less, in the case of a sale thereof,
the then market value thereof) less (ii) all out-of-pocket expenses reasonably
and actually incurred by Tenant in entering into the assignment, such as
customary real estate brokerage commissions, reasonable attorneys' fees, and the
cost of improvements or alterations made by Tenant expressly and solely for the
purpose of preparing the Premises for such assignment; and less (iii) the
unamortized value of Tenant's Alterations; or

          (b) in the case of a sublease, an amount equal to fifty percent (50%)
of (i) all rents, additional charges or other consideration payable to Tenant
under the sublease in excess of the Fixed Rent and Additional Rent accruing
during the term of the sublease in respect of the subleased space (at the rate
per square foot payable by Tenant hereunder with respect to the particular type
of space) pursuant to the terms hereof (including sums paid for the sale or
rental of Tenant's Property, less, in the case of the sale thereof, the then
market value thereof) less (ii) all expenses reasonably and actually incurred by
Tenant in entering into the sublease, such as customary real estate brokerage
commissions, reasonable attorneys' fees, and the cost of improvements or
alterations made by Tenant expressly and solely for the purpose of preparing the
subleased space for such subtenancy and the value of any so-called free rent or
tenant allowances, and less (iii) the unamortized value of Tenant's Alterations.
The sums payable under this clause shall be paid by Tenant to Landlord as
Additional Rent as and when payable by the subtenant to Tenant.

          SECTION 13.9 If Tenant is a partnership, corporation, limited
liability company, trust, entity or other than a natural Person, then the
transfer during the Term of this lease of more than forty-nine percent (49%) in
the aggregate of the beneficial ownership of Tenant or the issuance of any
additional shares or partnership or membership interests to the extent of more
than 49% in the aggregate of the beneficial ownership of Tenant hereunder, or
any merger, consolidation or combination of Tenant with any other entity or any
transfer of this Lease by operation of law or otherwise shall constitute an
assignment of this Lease; provided, however, that (a) if Tenant is a
publicly-traded corporation, the foregoing shall not apply to transfers of
publicly-traded stock in the ordinary course of such public trading, and (b)
transactions with a corporation or other entity into or with which Tenant is
merged or consolidated or to which substantially all of Tenant's assets are
transferred shall not be deemed an assignment hereunder so long as (i) such
transfer is for a legitimate independent business purpose and not for the
principal purpose of transferring this Lease, (ii) the successor to Tenant then
has at least: (A) an equity market capitalization determined in accordance with
GAAP consistently applied at least equal to that of Original Tenant on the date
of this Lease, (B) cash flow from operations determined in accordance with GAAP
consistently applied at least equal to that of Original Tenant on the date of
this Lease and (C) a credit profile by the major credit reporting agencies such
as Moody's, Standard & Poor and Dun & Bradstreet at least equal to that of
Original Tenant on the date of this Lease, and (iii) proof satisfactory to
Landlord of the foregoing shall have been delivered to Landlord at least ten
(10) days prior to the effective date of any such transaction.

          SECTION 13.10 (a) Notwithstanding anything to the contrary set forth
in this Lease, Tenant may, without Landlord's Approval, but upon not less than
ten (10) days' prior notice to Landlord and only upon compliance with this
Article 13, permit any Affiliate of Tenant to sublet all or any portion of the
Premises (i.e., including all then-existing Affiliate subleases) for any
Permitted Use, provided that no Event of Default shall then have occurred and be
continuing and provided, however, that should such Affiliate thereafter cease to
be an Affiliate of Tenant, such cessation shall be considered an


                                       13

<PAGE>

assignment of this Lease for which Landlord's Approval is required. Such
sublease shall not be deemed to vest in any such Affiliate any right or interest
in this Lease or the Premises nor shall it relieve, release, impair or discharge
any of Tenant's obligations hereunder, which shall be joint and several with
such Affiliate.

          (b) Notwithstanding anything to the contrary set forth in this Lease,
Tenant may, with Landlord's reasonable Approval, assign this Lease to any
Affiliate of Tenant for any Permitted Use, provided that no Event of Default
shall then have occurred and be continuing, and provided, however, that should
such Affiliate thereafter cease to be an Affiliate of Tenant, such cessation
shall be considered an assignment of this Lease for which compliance with all
this Article 13 is required. Any assignment pursuant to this Section 13.10(b)
shall not relieve, release, impair or discharge any of Tenant's obligations
hereunder, which shall be joint and several with such Affiliate.

          SECTION 13.11 (a) Any assignment or transfer, whether made with
Landlord's Approval pursuant to Section 13.1 hereof or without Landlord's
Approval to the extent permitted under Section 13.10 hereof, shall be made only
if, and shall not be effective until the assignee shall execute, acknowledge and
deliver to Landlord an agreement in form and substance reasonably satisfactory
to Landlord whereby the assignee shall assume the obligations of this Lease on
the part of Tenant to be performed or observed from and after the effective date
of such assignment or transfer, and whereby the assignee shall agree that the
provisions in Section 13.1 hereof shall, notwithstanding such assignment or
transfer, continue to be binding upon it in respect of all future assignments
and transfers. Any assignment or transfer made in violation of the provisions of
this Article 13 shall be void and of no force and effect.

          (b) The joint and several liability of Tenant and any immediate or
remote successor in interest of Tenant and the due performance of the
obligations of this Lease on Tenant's part to be performed or observed shall not
be discharged, released or impaired in any respect by any agreement or
stipulation made by Landlord, or any grantee or assignee of Landlord by way of
mortgage or otherwise, extending the time, or modifying any of the obligations
of this Lease, or by any waiver or failure of Landlord, or any grantee or
assignee of Landlord by way of mortgage or otherwise to enforce any of the
obligations of this Lease.

          (c) If this Lease be assigned, whether or not in violation of the
provisions of this Lease, Landlord may collect rent from the assignee. If the
Premises or any part thereof are licensed, sublet or used or occupied by anybody
other than Tenant, whether or not in violation of this Lease, Landlord may
collect rent from the subtenant or occupant upon an Event of Default by Tenant.
In either event, Landlord shall apply the net amount collected to the fixed
annual rent and additional rent in this Lease reserved, but no such assignment,
subletting, occupancy or collection shall be deemed a waiver of any of the
provisions of this Lease, or the acceptance of the assignee, subtenant, licensee
or occupant as tenant, or as a release of Tenant from the performance by Tenant
of Tenant's obligations under this Lease. The consent by Landlord to any
assignment, mortgaging, subletting, licensing or use or occupancy by others
shall not in any way be considered to relieve Tenant from obtaining the express
written consent of Landlord to any other or further assignment, mortgaging or
subletting or use or occupancy by others not expressly permitted by this
Article.

          (d) Tenant covenants that, notwithstanding any assignment, subletting
or transfer, whether or not in violation of the provisions of this Lease, and
notwithstanding the acceptance of fixed annual rent and/or additional rent by
Landlord from an assignee, subtenant, transferee, licensee, or any other party,
Tenant shall remain fully and personally liable for the payment of the fixed
annual rent and additional rents and for the other obligations of this Lease on
the part of Tenant to be performed or observed. Any violation of any provision
of this Lease by any assignee, subtenant or other occupant shall be deemed a
violation by the Original Tenant, the then subtenant or assignee and any other
persons who at any time was or were subtenant or assignee, it being the
intention and meaning that the Original Tenant, the then subtenant or assignee
and any other person(s) who at any time was or were subtenant or assignee shall
all be liable to Landlord (to the extent that any liability theretofore existed)
for any and all acts and omissions of any and all assignees, subtenants and
other occupants of the Premises.

ARTICLE 14 ACCESS TO PREMISES

          SECTION 14.1 Subject to the provisions of Section 5.3, Tenant shall
permit Landlord, Landlord's agents, and public utilities servicing the Building
to erect, use and maintain concealed ducts, pipes and conduits in and through
the Premises. Landlord and Landlord's agents, shall have the right to enter the
Premises at all reasonable times upon forty-eight (48) hours' prior notice
(except no such prior notice shall be required in case of a condition posing an
imminent threat of harm to persons or property), which notice may be oral, to
examine the same, to show them to prospective purchasers, Mortgagees, Lessors or
lessees of all or any part of the Building and their respective agents and
representatives or prospective tenants of the Premises, and to make such
repairs, alterations, improvements or additions (a) as Landlord may deem
reasonably necessary or desirable to the Premises or to any other portion of the
Property, or (b) which Landlord may elect to perform following Tenant's failure
to make repairs or perform any work which Tenant is obligated to make or perform
under this Lease, or (c) for the purpose of complying with Legal Requirements,
and Landlord shall be allowed to take all material


                                       14

<PAGE>

into and upon the Premises that may be reasonably required therefor without the
same constituting an eviction or constructive eviction of Tenant in whole or in
part and Fixed Rent and Additional Rent will not be abated while said repairs,
alterations, improvements or additions are being made, by reason of loss or
interruption of business of Tenant, or otherwise, unless caused by Landlord's
gross negligence or willful misconduct. Landlord covenants and agrees, in
exercising its rights under this Article 14, to use commercially reasonable
efforts to minimize interference with Tenant's use and enjoyment of the
Premises.

          SECTION 14.2 If Tenant shall not be present when for any reason entry
into the Premises shall be necessary or permissible, Landlord or Landlord's
agents may enter the same without rendering Landlord or such agents liable
therefor (if during such entry Landlord or Landlord's agents shall accord
reasonable care to Tenant's property), and without in any manner affecting this
Lease. Nothing in this Lease contained, however, shall be deemed or construed to
impose upon Landlord any obligation, responsibility or liability whatsoever for
the care, supervision or repair of the Building or any part thereof, other than
as in this Lease provided.

          SECTION 14.3 Subject to Section 5.3, Landlord shall have the right
from time to time to alter the Building and, without the same constituting an
actual or constructive eviction and without incurring any liability to Tenant
therefore provided that after such alteration Tenant has the use of facilities
that are similar to and provide substantially the same benefits to Tenant as
existed before such alteration to the extent same are reasonably required for
Tenant to operate its Mission Critical Data Center in the Premises, to change
the arrangement or location of entrances or passageways, doors and doorways, and
corridors, elevators, stairs, toilets, or other public parts of the Building and
to change the name, number or designation by which the Building is commonly
known. All parts (except surfaces facing the interior of the Premises) of all
walls, windows and doors bounding the Premises (including exterior Building
walls, exterior corridor walls, exterior doors and entrances other than doors
and entrances solely servicing the Premises), all balconies, terraces and roofs
adjacent to the Premises, all space in or adjacent to the Premises used for
shafts, stacks, stairways, chutes, pipes, conduits, ducts, fan rooms, heating,
air cooling, plumbing and other mechanical facilities, service closets and other
Building facilities are not part of the Premises, and Landlord shall have the
use thereof, as well as access thereto through the Premises for the purposes of
operation, maintenance, alteration and repair thereto provided such access does
not cause a material adverse effect on Tenant's use and operations or Tenant's
rights under this Lease.

          SECTION 14.4 Any reservation of a right by Landlord to enter upon the
Premises and to make or perform any repairs, restorations and replacements,
Alterations or other work in, to or about the Premises which, in the first
instance, is the obligation of Tenant pursuant to this Lease, shall not be
deemed to: (a) impose any obligation on Landlord to do so, (b) render Landlord
liable (to Tenant or any third party) for the failure to do so, or (c) relieve
Tenant from any obligation to indemnify Landlord as otherwise provided elsewhere
in this Lease.

ARTICLE 15 CERTIFICATE OF OCCUPANCY

          SECTION 15.1 Tenant shall not at any time use or occupy the Premises
in violation of the certificate of occupancy at such time issued for the
Premises or for the Building and in the event that any Governmental Authority
shall hereafter contend or declare by notice, violation, order or in any other
manner whatsoever that the Premises are used for a purpose which is a violation
of such certificate of occupancy, Tenant shall upon thirty (30) days' written
notice (or such shorter period as may be required under applicable Legal
Requirements from Landlord or any Governmental Authority, immediately
discontinue such use of the Premises.

ARTICLE 16 DEFAULT

          SECTION 16.1 Each of the following events shall be an "Event of
Default" under this Lease:

          (a) if Tenant defaults in the payment when due of any installment of
Fixed Rent and such default continues for a period of ten (10), or if Tenant
defaults in the payment when due of Additional Rent and such default continues
for a period of five (5) days after notice thereof from Landlord; provided,
however, that if Tenant shall default in the timely payment of Fixed Rent or
Additional Rent, and any such default shall occur for more than two (2)
consecutive months or more than three (3) times in any period of twenty-four
(24) months, then notwithstanding that such defaults shall have each been cured
within the applicable period provided above, upon any further monetary default,
Landlord may serve a notice of termination upon Tenant without affording to
Tenant an opportunity to cure such further default; or

          (b) if Tenant's interest in this Lease is transferred in violation of
Article 13 hereof; or

          (c) if the Premises or a substantial portion thereof becomes vacant or
abandoned; or

          (d) (i) if Tenant admits in writing its inability to pay its debts as
they become due; (ii) if Tenant commences or institutes any case proceeding or
other action (A) seeking relief as a debtor, or to adjudicate it a bankrupt or
insolvent, or


                                       15

<PAGE>

seeking reorganization, arrangement, adjustment, winding-up, liquidation,
dissolution, composition or other relief with respect to it or its debts under
any existing or future Legal Requirements of any jurisdiction, domestic or
foreign, relating to bankruptcy, insolvency, reorganization or relief of
debtors, or (B) seeking appointment of a receiver, trustee, custodian or other
similar official for it or for all or any substantial part of its property;
(iii) if Tenant makes a general assignment for the benefit of creditors; or (iv)
if any case, proceeding or other action is commenced or instituted against
Tenant (A) seeking to have an order for relief entered against it as debts, or
to adjudicate it a bankrupt or insolvent, or seeking reorganization,
arrangement, adjustment, winding-up, liquidation, dissolution, composition or
other relief with respect to it or its debts under any existing or future Legal
Requirements of any jurisdiction, domestic or foreign, relating to bankruptcy,
insolvency, reorganization or relief of debtors, or (B) seeking appointment of a
receiver, trustee, custodian or other similar official for it or for all or any
substantial part of its property, which either (1) results in any such entry of
an order for relief, adjudication of bankruptcy or insolvency or such an
appointment or the issuance or entry of any other order having a similar effect
or (2) remains undismissed for a period of one hundred twenty (120) days; (v) if
any case, proceeding or other action is commenced or instituted against Tenant
seeking issuance of a warrant of attachment, execution, distraint or similar
process against all or any substantial part of its property which results in the
entry of an order for any such relief which has not been vacated, discharged, or
stayed or bonded pending appeal within one hundred twenty (120) days from the
entry thereof; (vi) if Tenant takes any action in furtherance of, or indicating
its consent to, approval of, or acquiescence in, any of the acts set forth in
Sections 16.1(d) (ii), (iii), (iv) or (v); or (vii) if a trustee, receiver or
other custodian is appointed for any substantial part of the assets of Tenant,
which appointment is not vacated or effectively stayed within sixty (60) days,
or if any such vacating or stay does not thereafter remain in effect; or

          (e) if Tenant defaults in the observance or performance of any other
term, covenant or condition of this Lease on Tenant's part to be observed or
performed and Tenant fails to remedy such default within thirty (30) days after
notice by Landlord to Tenant of such default, or, if such default is of such a
nature that it cannot be completely remedied within said period of thirty (30)
days, if Tenant fails to commence to remedy such default within such thirty (30)
day period, or fails thereafter to diligently prosecute to completion all steps
necessary to remedy such default; provided, however, that if Tenant shall
default in the observance or performance of any term, covenant or condition of
this Lease more than two (2) times in any period of twenty-four (24) months,
then notwithstanding that such defaults shall have each been cured within the
applicable period provided above, upon any further default, Landlord may serve a
three (3) days' notice of termination upon Tenant without affording to Tenant an
opportunity to cure such further default; and

          (f) if Tenant or any Affiliate of Tenant defaults beyond applicable
grace and notice periods in the payment of any fixed rent, or additional rent or
other sums due or in the timely performance of any obligations or under any
other lease of space, license agreement or similar document in the Building, or
if any such lease, license agreement or similar document is terminated by
Landlord or any Affiliate of Landlord as a result of a default by the tenant,
licensee or any party thereunder after applicable notice and grace periods.

          SECTION 16.2 If an Event of Default occurs, Landlord may at any time
thereafter give written notice to Tenant stating that this Lease and the Term
shall expire and terminate on the date specified in such notice, which date
shall not be less than three (3) days after the giving of such notice. If
Landlord gives such notice, this Lease and the Term and all rights of Tenant
under this Lease shall expire and terminate as if the date set forth in such
notice were the stated Expiration Date and Tenant immediately shall quit and
surrender the Premises, but Tenant shall remain liable as in this Leaseafter
provided. Anything contained in this Lease to the contrary notwithstanding, if
such termination shall be stayed by order of any court having jurisdiction over
any proceeding described in Section 16.1(d), or by federal or state statute,
then, following the expiration of any such stay, or if the trustee appointed in
any such proceeding, Tenant or Tenant as debtor-in-possession shall fail to
assume Tenant's obligations under this Lease within the period prescribed
therefor by Legal Requirements or within one hundred twenty (120) days after
entry of the order for relief or as may be allowed by the court, or if said
trustee, Tenant or Tenant as debtor-in-possession shall fail to provide adequate
protection of Landlord's right, title and interest in and to the Premises or
adequate assurance of the complete and continuous future performance of Tenant's
obligations under this Lease Landlord, to the extent permitted by Legal
Requirements or by leave of the court having jurisdiction over such proceeding,
shall have the right, at its election, to terminate this Lease on seven (7)
days' notice to Tenant, Tenant as debtor-in-possession or said trustee and upon
the expiration of said seven (7) day period this Lease shall cease and expire as
set forth above and Tenant, Tenant as debtor-in-possession or said trustee shall
immediately quit and surrender the Premises as aforesaid.

          SECTION 16.3 If, at any time, (a) Tenant shall be comprised of two (2)
or more Persons, (b) Tenant's obligations under this Lease shall have been
guaranteed by any Person other than Tenant, or (c) Tenant's interest in this
Lease shall have been assigned, the word "Tenant" as used in Section 16.1(d),
shall be deemed to mean any one or more of the Persons primarily or secondarily
liable for Tenant's obligations constituting Tenant under this Lease. Any monies
received by Landlord from or on behalf of Tenant during the pendency of any
proceeding of the types referred to in Section 16.1(d) shall be deemed paid as
compensation for the use and occupation of the Premises and the acceptance of
any such compensation by Landlord shall not be deemed an acceptance of Fixed
Rent and/or Additional Rent or a waiver on the part of Landlord of any rights
under this Lease.


                                       16

<PAGE>

ARTICLE 17 REMEDIES AND DAMAGES

          SECTION 17.1 (a) If an Event of Default shall occur: (i) Tenant shall
quit and peacefully surrender the Premises to Landlord, and Landlord and its
agents may immediately, or at any time after such Event of Default or after the
date upon which this Lease and the Term shall expire and come to an end,
re-enter the Premises or any part thereof, without notice, either by summary
proceedings, or by any other applicable action or proceeding, or by legal force
or other legal means (without being liable to indictment, prosecution or damages
therefor), and may repossess the Premises and dispossess Tenant and any other
Persons from the Premises and remove any and all of their property and effects
from the Premises; and (ii) Landlord, at Landlord's option, may relet the whole
or any part or parts of the Premises from time to time, either in the name of
Landlord or otherwise, to such tenant or tenants, for such term or terms ending
before, on or after the Expiration Date, at such rental or rentals and upon such
other conditions, which may include concessions and free rent periods, as
Landlord, in its sole discretion, may determine; provided, however, that
Landlord shall have no obligation to relet the Premises or any part thereof and
shall in no event be liable for refusal or failure to relet the Premises or any
part thereof, or, in the event of any such reletting, for refusal or failure to
collect any rent due upon any such reletting, and no such refusal or failure
shall operate to relieve Tenant of any liability under this Lease or otherwise
affect any such liability, and Landlord, at Landlord's option, may make such
repairs, replacements, alterations, additions, improvements, decorations and
other physical changes in and to the Premises as Landlord, in its sole
discretion, considers advisable or necessary in connection with any such
reletting or proposed reletting, without relieving Tenant of any liability under
this Lease or otherwise affecting any such liability.

          (b) Tenant hereby waives the service of any notice of intention to
re-enter or to institute legal proceedings to that end which may otherwise be
required to be given under any present or future Legal Requirements. Tenant, on
its own behalf and on behalf of all Persons claiming through or under Tenant,
including all creditors, does further hereby waive any and all rights which
Tenant and all such Persons might otherwise have under any present or future
Legal Requirements to redeem the Premises, or to re-enter or repossess the
Premises, or to restore the operation of this Lease, after (i) Tenant shall have
been dispossessed by a judgment or by warrant of any court or judge, (ii) any
re-entry by Landlord, or (iii) any expiration or termination of this Lease and
the Term, whether such dispossess, re-entry, expiration or termination shall be
by operation of law or pursuant to the provisions of this Lease. The words
"re-enter," "re-entry" and "re-entered" as used in this Lease shall not be
deemed to be restricted to their technical legal meanings. In the event of a
breach or threatened breach by Tenant, or any Persons claiming through or under
Tenant, of any term, covenant or condition of this Lease, Landlord shall have
the right to enjoin such breach and the right to invoke any other remedy allowed
by Legal Requirements or in equity as if re-entry, summary proceedings and other
special remedies were not provided in this Lease for such breach. The rights to
invoke the remedies in this Leasebefore set forth are cumulative and shall not
preclude Landlord from invoking any other remedy allowed at law or in equity.

          SECTION 17.2 (a) If this Lease and the Term shall expire and come to
an end as provided in Article 16, or by or under any summary proceeding or any
other action or proceeding, or if Landlord shall re-enter the Premises as
provided in Section 17.1, or by or under any summary proceeding or any other
action or proceeding, then, in any of such events:

               (i) Tenant shall pay to Landlord all Fixed Rent and Additional
Rent payable under this Lease by Tenant to Landlord to the date upon which this
Lease and the Term shall have expired and come to an end or to the date of
re-entry upon the Premises by Landlord;

               (ii) Tenant also shall be liable for and shall pay to Landlord,
as damages, any deficiency (the "Deficiency" or "Deficiencies") between (A)
Fixed Rent and Additional Rent for the period which otherwise would have
constituted the unexpired portion of the Term (conclusively presuming the
Additional Rent for each year thereof to be the same as was payable for the year
immediately preceding such termination or re-entry), and (B) the net amount, if
any, of rents collected under any reletting effected pursuant to the provisions
of Section 17.1(a)(ii) for any part of such period (first deducting from the
rents collected under any such reletting all of Landlord's expenses in
connection with the termination of this Lease, Landlord's re-entry upon the
Premises and with such reletting including all repossession costs, brokerage
commissions, legal expenses, reasonable attorneys' fees and disbursements,
alteration costs and other expenses of preparing the Premises for such
reletting). Tenant shall pay the Deficiency in monthly installments on the days
specified in this Lease for payment of installments of Fixed Rent, and Landlord
shall be entitled to recover from Tenant each monthly Deficiency as the same
shall arise. No suit to collect the amount of the Deficiency for any month shall
prejudice Landlord's right to collect the Deficiency for any subsequent month by
a similar proceeding; and

               (iii) whether or not Landlord shall have collected any monthly
Deficiency as aforesaid, Landlord shall be entitled to recover from Tenant, and
Tenant shall pay to Landlord, on demand, in lieu of any further Deficiency as
and for liquidated and agreed final damages, a sum equal (A) to the amount by
which the Fixed Rent and Additional Rent for the period which otherwise would
have constituted the unexpired portion of the Term (conclusively presuming the
Additional Rent for each year thereof to be the same as was payable for the year
immediately preceding such termination or re-entry)


                                       17

<PAGE>

exceeds (B) the then fair and reasonable rental value of the Premises, including
Additional Rent for the same period, both discounted to present value at the
rate of four percent (4%) per annum less (C) the aggregate amount of
Deficiencies previously collected by Landlord, pursuant to the provisions of
Section 17.2(a)(ii) for the same period. If, before presentation of proof of
such liquidated damages to any court, commission or tribunal, Landlord shall
have relet the Premises or any part thereof for the period which otherwise would
have constituted the unexpired portion of the Term, or any part thereof, the
amount of net rents collected in connection with such reletting shall be deemed,
prima facie, to be the fair and reasonable rental value for the part or the
whole of the Premises so relet during the term of the reletting.

          (b) If Landlord shall relet the Premises, or any part thereof,
together with other space in the Building, the net rents collected under any
such reletting and the expenses of any such reletting shall be equitably
apportioned for the purposes of this Section 17.2. Tenant shall in no event be
entitled to any rents collected or payable under any reletting, whether or not
such rents shall exceed the Fixed Rent reserved in this Lease. Nothing contained
in Article 16 or this Article 17 shall be deemed to limit or preclude the
recovery by Landlord from Tenant of the maximum amount allowed to be obtained as
damages by any statute or rule of Legal Requirements, or of any sums or damages
to which Landlord may be entitled in addition to the damages set forth in this
Section 17.2.

          (c) In the event of a breach or threatened breach on the part of
Tenant with respect to any of the covenants, agreements, terms, provisions or
conditions on the part of or on behalf of Tenant to be kept, observed or
performed, Landlord shall also have the right to obtain injunctive relief.

          (d) The specified remedies to which Landlord may resort under this
Lease are cumulative and concurrent, and are not intended to be exclusive of
each other or of any other remedies or means of redress to which Landlord may
lawfully be entitled at any time, and Landlord may invoke any remedy allowed
under this Lease or at law or in equity as if specific remedies were not in this
Lease provided for, and the exercise by Landlord of any one or more of the
remedies allowed under this Lease or in law or in equity shall not preclude the
simultaneous or later exercise by the Landlord of any or all other remedies
allowed under this Lease or in law or in equity.

ARTICLE 18 FEES AND EXPENSES

          SECTION 18.1 If an Event of Default shall occur under this Lease or if
Tenant shall do or permit to be done any act or thing upon the Premises, the
Building or the Property which would cause Landlord to be in default under any
Superior Lease or Mortgage or any other document superior to this Lease, or if
Tenant shall fail to comply with its obligations under this Lease and the
preservation of property or the safety of any tenant, occupant or other Person
is threatened, Landlord may, after reasonable prior notice to Tenant except in
the event of an imminent threat of harm to persons or property where no notice
is required, perform the same for the account of Tenant or make any expenditure
or incur any obligation for the payment of money for the account of Tenant. All
amounts expended by Landlord in connection with the foregoing, including
reasonable attorneys' fees and disbursements in instituting, prosecuting or
defending any action or proceeding or recovering possession, and the cost
thereof, with interest thereon at the Default Rate, shall be deemed to be
Additional Rent hereunder and shall be paid by Tenant to Landlord within thirty
(30) days of rendition of any bill or statement to Tenant therefore. Upon
request, Landlord shall provide Tenant with reasonable supporting documentation
of the costs incurred by Landlord.

ARTICLE 19 NO REPRESENTATIONS BY LANDLORD

          SECTION 19.1 Landlord and Landlord's agents have made no warranties,
representations, statements or promises with respect to (a) the rentable and
usable areas of the Premises or the Building, (b) the compliance with applicable
Legal Requirements of the Premises, the Building or the Property, or (c) the
suitability of the Premises or the Property for any particular use or purpose.
No rights, easements or licenses are acquired by Tenant under this Lease, by
implication or otherwise, except as expressly set forth in this Lease. This
Lease (including any Exhibits referred to in this Lease and all supplementary
agreements provided for in this Lease) contains the entire agreement between the
parties and all understandings and agreements previously made between Landlord
and Tenant are merged in this Lease, which alone fully and completely expresses
their agreement. Tenant is entering into this Lease after full investigation,
and is not relying upon any statement or representation made by Landlord not
embodied in this Lease.

ARTICLE 20 END OF TERM

          SECTION 20.1 Upon the expiration or other termination of this Lease,
Tenant shall quit and surrender to Landlord the Premises, vacant, broom-clean,
in good order and condition, ordinary wear and tear and damages for which Tenant
is not responsible under the terms of this Lease excepted, and Tenant shall
remove all of Tenant's Property and any Tenant Alterations and Data Center
Configuration Work from the Premises and the Property to the extent required
under Section 3.3, and this obligation shall survive the expiration or sooner
termination of the Term. If the last day of the Term or any renewal


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<PAGE>

or extension thereof falls on Saturday or Sunday, this Lease shall expire on the
Business Day immediately preceding. Tenant expressly waives for itself and for
any Person claiming through or under Tenant, any rights which Tenant or any such
Person may have under the provisions of any applicable Legal Requirement then in
force in connection with any holdover summary proceedings which Landlord may
institute to enforce the foregoing provisions of this Article 20.

          SECTION 20.2 Tenant acknowledges that Tenant or any subtenant of
Tenant remaining in possession of the Premises after the expiration or earlier
termination of this Lease would create an unusual hardship for Landlord and for
any prospective tenant. Tenant, therefore, covenants that if for any reason
Tenant or any assignee or subtenant of Tenant shall fail to vacate and surrender
possession of the Premises or any part thereof on or before the expiration or
earlier termination of this Lease and the Term, then Tenant's continued
possession of the Premises shall be as a month-to-month tenant, during which
time, without prejudice and in addition to any other rights and remedies
Landlord may have hereunder or at law, Tenant shall pay to Landlord for each
month and for each portion of any month during which Tenant holds over, an
amount equal to: (a) for the first thirty (30) days during which Tenant holds
over, the total monthly amount of Fixed Rent and Additional Rent payable
hereunder immediately prior to such termination (the "Existing Rent") multiplied
by one hundred fifty percent (150%), and (b) two hundred percent (200%) of the
Existing Rent thereafter. The provisions of this Section 20.2 shall not in any
way be deemed to (i) permit Tenant to remain in possession of the Premises after
the Expiration Date or sooner termination of this Lease or (ii) imply any right
of Tenant to use or occupy the Premises upon expiration or termination of this
Lease and the Term, and no acceptance by Landlord of payments from Tenant after
the Expiration Date or sooner termination of the Term shall be deemed to be
other than on account of the amount to be paid by Tenant in accordance with the
provisions of this Article 20. Tenant's obligations under this Article shall
survive the expiration or earlier termination of this Lease.

          SECTION 20.3 In addition to making all required payments of Fixed Rent
and Additional Rent, Tenant shall, in the event of Tenant's failure to surrender
the Premises upon the expiration or other termination of this Lease, as and in
the manner aforesaid, also indemnify and hold Landlord harmless from and against
any and all cost, expense, damage, claim, loss or liability resulting from any
delay or failure by Tenant in so surrendering the Premises, including any
consequential damages suffered by Landlord and any claims made by any succeeding
occupant founded on such delay or failure, and any and all reasonable attorneys'
fees, disbursements and court costs incurred by Landlord in connection with any
of the foregoing.

          SECTION 20.4 Tenant's obligations under this Article 20 (including the
indemnity) shall survive the expiration or earlier termination of this Lease.

ARTICLE 21 QUIET ENJOYMENT

          SECTION 21.1 Provided no Event of Default has occurred and is
continuing, Tenant may peaceably and quietly enjoy the Premises without
hindrance by Landlord or any Person lawfully claiming through or under Landlord
subject to the terms and conditions of this Lease.

ARTICLE 22 NO WAIVER, NON-LIABILITY

          SECTION 22.1 No act or thing done by Landlord or Landlord's agents
during the Term shall be deemed an acceptance of a surrender of the Premises,
and no agreement to accept such surrender shall be valid unless in writing and
signed by Landlord. The delivery of keys to any employee of Landlord or of
Landlord's agents shall not operate as a termination of this Lease or a
surrender of the Premises. Any employee of Landlord or its agents to whom any
property shall be entrusted by or on behalf of Tenant shall be deemed to be
acting as Tenant's agent, with respect to such property and neither Landlord nor
its agents shall be liable for any damage to property of Tenant or of others
entrusted to employees of Landlord, or its agents, nor for the loss of or damage
to any property of Tenant by theft or otherwise.

          SECTION 22.2 The failure of either parties to seek redress for
violation of, or to insist upon the strict performance of, any covenant or
condition of this Lease, or any of the Rules and Regulations, shall not prevent
a subsequent act, which would have originally constituted a violation, from
having all of the force and effect of an original violation. No provision of
this Lease shall be deemed to have been waived by either party, unless such
waiver is in writing signed by the party against whom the waiver is sought to be
enforced. No payment by Tenant or receipt by Landlord of a lesser amount than
the monthly Fixed Rent or any Additional Rent shall be deemed to be other than
on account of the next installment of Fixed Rent or Additional Rent, as the case
may be, or as Landlord may elect to apply same, nor shall any endorsement or
statement on any check or any letter accompanying any check or payment as Fixed
Rent or Additional Rent be deemed an accord and satisfaction, and Landlord may
accept such check or payment without prejudice to Landlord's right to recover
the balance of such Fixed Rent or Additional Rent or pursue any other remedy in
this Lease provided. Any executory agreement hereafter made shall be ineffective
to change, modify, discharge or effect an abandonment of this Lease in whole or
in part unless such


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<PAGE>

executory agreement is in writing and signed by the party against whom
enforcement of the change, modification, discharge or abandonment is sought.

          SECTION 22.3 Unless caused by Landlord's gross negligence or willful
misconduct, neither Landlord nor its agents shall be liable for any injury or
damage to persons or property or interruption of Tenant's business resulting
from fire, explosion, falling plaster, steam, gas, electricity, water, rain or
snow or leaks from any part of the Building or from the pipes, appliances or
plumbing works or from the roof, street or subsurface or from any other place or
by dampness or by any other cause of whatsoever nature; nor shall Landlord or
its agents be liable for any such damage caused by other tenants or persons in
the Building or caused by construction of any private, public or quasi-public
work; nor shall Landlord be liable for any latent defect in the Premises or in
the Building. Nothing in the foregoing shall affect any right of Landlord to the
indemnity from Tenant to which Landlord may be entitled under Article 28 in
order to recoup for payments made to compensate for losses of third parties.

ARTICLE 23 WAIVER OF TRIAL BY JURY

          SECTION 23.1 The respective parties hereto shall and they hereby do
waive trial by jury in any action, proceeding or counterclaim brought by either
of the parties hereto against the other on any matters whatsoever arising out of
or in any way connected with this Lease, the relationship of Landlord and
Tenant, Tenant's use or occupancy of the Premises, or for the enforcement of any
remedy under any statute, emergency or otherwise. If Landlord commences any
summary proceeding against Tenant, Tenant will not interpose any counterclaim of
whatever nature or description in any such proceeding (unless failure to impose
such counterclaim would preclude Tenant from asserting in a separate action the
claim which is the subject of such counterclaim), and will not seek to
consolidate such proceeding with any other action which may have been or will be
brought in any other court by Tenant.

ARTICLE 24 INABILITY TO PERFORM

          SECTION 24.1 This Lease and the obligation of Tenant to pay Fixed Rent
and Additional Rent hereunder and perform all of the other covenants and
agreements hereunder on the part of Tenant to be performed will not be affected,
impaired or excused because Landlord is unable to fulfill any of its obligations
under this Lease expressly or impliedly to be performed by Landlord or because
Landlord is unable to make, or is delayed in making any repairs, additions,
alterations, improvements or decorations or is unable to supply or is delayed in
supplying any equipment or fixtures, if Landlord is prevented or delayed from so
doing by reason of strikes or labor troubles or by accident, or by any cause
whatsoever reasonably beyond Landlord's control, including laws, governmental
preemption in connection with a national emergency or by reason of any Legal
Requirements or by reason of the conditions of supply and demand which have been
or are affected by war or other emergency but not by reason of Landlord's
unavailability of funds or other financial difficulty by Landlord (collectively
"Unavoidable Delays").

ARTICLE 25 BILLS AND NOTICES

          SECTION 25.1 Except as otherwise expressly provided in this Lease, any
bills, statements, Approvals, notices, demands, requests or other communications
given or required to be given under this Lease shall be in writing and shall be
deemed sufficiently given or rendered if delivered by hand (against a signed
receipt), sent by a nationally recognized overnight courier service, or sent by
registered or certified mail (return receipt requested) (except that bills or
demands for Rent may be sent by regular mail) and addressed:

          (a) if to Tenant, (i) at Tenant's address at the Premises, or (b) at
any place where Tenant or any agent or employee or Tenant may be found if mailed
subsequent to Tenant's abandoning or surrendering the Premises; or

          (b) if to Landlord, as follows: (i) at its address as first stated
above in this Lease, Attention: Mr. Todd Aaron; and (ii) with a copy at the same
time and in the same manner to: Mintz, Levin, Cohn, Ferris, Glovsky and Popeo,
P.C., 666 Third Avenue, New York, New York 10017, Attention: Jeffrey A.
Moerdler, Esq.

Any such bill, statement, Approval, notice, demand, request or other
communication shall be deemed to have been rendered or given: (A) on the date
when it shall have been hand delivered, (B) or three (3) Business Days from the
date when it shall have been mailed, or (C) one (1) Business Day from the date
when it shall have been sent by overnight courier service for next Business Day
delivery. Attorneys for either party may give any notice specified in this Lease
on behalf of such party. Landlord or Tenant may change the address(es) to which
any such bill, statement, Approval, notice, demand, request or other
communication may be sent by a notice given to the other parties in accordance
with this Article 25.


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<PAGE>

ARTICLE 26 RULES AND REGULATIONS

          SECTION 26.1 Landlord reserves the right, from time to time on not
less than thirty (30) days prior notice to Tenant, to adopt additional
reasonable Rules and Regulations and to amend the Rules and Regulations now or
then in effect, provided same do not materially adversely reduce Tenant's rights
under this Lease or materially and adversely affect the reasonable conduct of
Tenant's operations in the Premises. Tenant and Tenant's contractors, employees,
agents, and licensees shall comply with the Rules and Regulations, as so
supplemented or amended. Nothing contained in this Lease shall be construed to
impose upon Landlord any duty or obligation to enforce the Rules and Regulations
or terms, covenants or conditions in any other lease against any other tenant,
and Landlord shall not be liable to Tenant for violation of the same by another
tenant, its employees, agents, visitors or licensees. Notwithstanding anything
to the contrary contained in this Lease: (a) Landlord shall not enforce against
Tenant any Rules and Regulations against Tenant in a discriminatory manner; and
(b) if there shall be any specific inconsistencies between this Lease and the
Rules and Regulations attached as an Exhibit to this Lease then the express
provisions of this Lease shall prevail.

ARTICLE 27 BROKER

          SECTION 27.1 Each of Landlord and Tenant represents and warrants to
the other that it has not dealt with any broker in connection with this Lease
other than the Broker and that to the best of its knowledge and belief, no other
broker, finder or similar Person procured or negotiated this Lease or is
entitled to any fee or commission in connection herewith. Landlord shall pay a
commission to the Broker pursuant to a separate agreement with the Broker. Each
of Landlord and Tenant shall indemnify, defend, protect and hold the other party
harmless from and against any and all losses, liabilities, damages, claims,
judgments, fines, suits, demands, costs, interest and expenses of any kind or
nature (including reasonable attorneys' fees and disbursements) which the
indemnified party may incur by reason of any claim of or liability to any
broker, finder or like agent (other than Broker) arising out of any dealings
claimed to have occurred between the indemnifying party and the claimant in
connection with this Lease, or the above representation being false. The
provisions of this Article 27 shall survive the expiration or earlier
termination of the Term of this Lease.

ARTICLE 28 INDEMNITY

          SECTION 28.1 Tenant shall not do or permit any act or thing to be done
upon the Premises which may subject Landlord to any, liability or responsibility
for injury, damages to persons or property or to any liability by reason of any
violation of law or of any Legal Requirement, but shall exercise such control
over the Premises as to fully protect Landlord against any such liability.
Subject to the provisions of Section 10.2(b) hereof, Tenant shall defend,
indemnify and save harmless Landlord as set forth in this Lease below from and
against (a) all claims against Landlord arising from the negligence of Tenant,
its contractors, licensees, agents, servants, employees, invitees or visitors;
(b) all claims against Landlord arising from any accident, injury or damages
whatsoever caused to any person or to the property of any person and occurring
during the Term in or about the Premises, or other portions of the Property used
or occupied by Tenant; (c) all claims against Landlord arising from any
accident, injury or damage occurring outside of the Premises but anywhere within
or about the Property, where such accident, injury or damage results or is
claimed to have resulted from an act, omission or negligence of Tenant or
Tenant's agents, employees, contractors, licensees, servants, invitees or
visitors; (d) any breach, violation or nonperformance of any covenant, condition
or agreement in this Lease set forth and contained on the part of Tenant to be
fulfilled, kept, observed and performed; (e) the actual presence of hazardous
materials on the Premises or the Property which is caused or permitted by
Tenant, its employees, contractors, or invitees; (f) any environmental claim
relating in any way to Tenant's operation or use of the Premises or the
Property; (g) all claims arising in connection with the emission of
electromagnetic radiation which is caused or permitted by Tenant or its
equipment; (h) any claims arising in connection with the default or alleged
default under contracts or other agreements between Tenant and its customers;
(i) any and all costs and expenses that Landlord may incur in complying with any
Legal Requirements necessitated by any act or failure to act by Tenant that is
inconsistent with (x) the use of the Premises as a first class Mission Critical
Data Center, or (y) the terms of this Lease, any and all costs and expenses that
Landlord may incur in studying, assessing, containing, removing, remedying,
remediating, mitigating, or otherwise responding to, the presence or release of
any hazardous material at, in, on, under or from the Premises; (j) any and all
costs and expenses for which Landlord may be liable to any Governmental
Authority, Mortgagee or Lessor for studying, assessing, containing, removing,
remedying, remediating, mitigating, or otherwise responding to, the presence or
release of a hazardous material at, in, on, under, from or relating to Tenant's
operations on, the Premises; and (k) any and all fines or penalties assessed, or
threatened to be assessed, upon Landlord or liabilities to third parties by
reason of a failure of Tenant to comply with any obligations, covenants or
conditions set forth in Section 7.1. This indemnity and hold harmless agreement
shall be an indemnity of Landlord, and any partner, shareholder, director,
officer, principal, employee or agent, directly and indirectly, of Landlord,
from and against any and all obligations (including removal and remedial
actions), losses, claims, suits, judgments, liabilities, penalties, damages
(including consequential and


                                       21

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


punitive damages), costs and expenses (including reasonable attorneys' and
consultants' fees and expenses) of any kind or nature incurred in or in
connection with any such claim or proceeding brought thereon, and the defense
thereof.

          SECTION 28.2 The provisions of this Article 28 shall survive the
expiration or termination of this Lease.

ARTICLE 29

                                       *


                                       22

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


                                        *


ARTICLE 30 EXTENSION OPTION

          SECTION 30.1 Tenant shall have the right, at its option (each, an
"Extension Option"), to extend the initial Term of this Lease, for the entire
Premises (as the same may have been increased), for one (1) extension term (the
"Extension Term"). The Extension Term shall commence on the day following the
Expiration Date (the "Extension Term Commencement Date") and shall expire on the
day preceding the fifth (5th) anniversary of the Fixed Expiration Date (the
"Extension Term Expiration Date"). Tenant shall have no right to exercise the
Extension Option unless all of the following conditions are satisfied on the
date of the Extension Notice (as defined below) and on the Extension Term
Commencement Date: (a) neither an Event of Default nor a monetary default
(whether or not a notice has been sent) shall have occurred and be continuing
under this Lease or under any other agreement between Landlord or an Affiliate
of Landlord and Tenant or an Affiliate of Tenant; (b) the Original Tenant (or a
permitted assignee, sublessor, successor or transferee pursuant to Section
13.9(b), but not any other assignee or successor tenant) shall occupy not less
than eighty-five percent (85%) of the Useable Square Feet of the Premises; and
(c) there shall not have occurred any material adverse change in the financial
condition of Tenant from the condition described in the financial statements
submitted by Tenant to Landlord in connection with this Lease; (d) Tenant's: on
the date of this Lease and on the date of the last prior exercise of an
Extension Option; (e) no default (after notice if required and expiration of any
applicable cure period) by Tenant exists under any loan, debt, bank or similar
facility or agreement; and (f) proof satisfactory to Landlord of the foregoing
shall have been delivered to Landlord together with the notice exercising such
Extension Option.

          SECTION 30.2 No separate instrument of extension shall be required for
Tenant to exercise its Extension Option. If Tenant elects to extend this Lease
for the Extension Term, Tenant shall exercise such option by sending to Landlord
written notice thereof (the "Extension Notice") not less than ten(10) months
prior to the Expiration Date, and TIME SHALL BE OF THE ESSENCE with respect to
the giving of the Extension Notice. If Tenant shall send the Extension Notice
within the time and in the manner in this Lease provided, this Lease shall be
deemed extended for the Extension Term upon the terms, covenants and conditions
in this Lease contained, with the exception of Fixed Rent.

          SECTION 30.3 Fixed Rent for the Extension Term shall be determined as
of the date of the Extension Notice and shall be the greater of (a) the annual
fair market rental value ("FMV") of the Premises as a Mission Critical Data
Center for the relevant Extension Term, as determined by Landlord as if the
relevant Extension Term were for the number of years comparable to the leases
Landlord is then typically entering into, and otherwise in accordance with
Section 30.4 of this Lease, or (b) *% of the total of the Fixed Rent payable
during the preceding year. During each Extension term, the Fixed Rent shall
increase by * percent (*%) compounded cumulatively on each anniversary of the
Commencement Date.

          SECTION 30.4 Within fifteen (15) days after the giving by Tenant of a
Extension Notice, Landlord will notify Tenant of the amount of the Fixed Rent
for the Extension Term as determined by Landlord pursuant to Section 30.3 (a
"Rental Notice"). Tenant may withdraw the Extension Notice by written notice
to Landlord received by Landlord within fifteen (15) days after the giving of
the Rental Notice, TIME BEING OF THE ESSENCE as to Landlord's receipt of any


                                       23

<PAGE>

such withdrawal notice. After determination has been made of the FMV for the
Premises, the parties shall execute and deliver to each other an agreement
setting forth the Fixed Rent therefore as so determined.

ARTICLE 31 [INTENTIONALLY OMITTED]

ARTICLE 32 [INTENTIONALLY OMITTED]

ARTICLE 33 [INTENTIONALLY OMITTED]

ARTICLE 34 EXCULPATION; APPROVALS; LEGAL FEES

          SECTION 34.1 (a) The obligations of Landlord under this Lease shall
not be binding upon Landlord named in this Lease after the sale, conveyance,
assignment or transfer by such Landlord (or upon any subsequent landlord after
the sale, conveyance, assignment or transfer by such subsequent landlord) of its
interest in the Building and in the event of any such sale, conveyance,
assignment or transfer, Landlord shall be and hereby is entirely freed and
relieved of all covenants and obligations of Landlord hereunder, and the
transferee of Landlord's interest in the Building shall be deemed to have
assumed all obligations under this Lease, including claims accrued prior to such
sale, conveyance, assignment or transfer. Prior to any such sale, conveyance,
assignment or transfer, the liability of Landlord for Landlord's obligations
under this Lease shall be limited to Landlord's interest in the Building (and
the proceeds of any insurance or condemnation award with respect thereto) and
Tenant shall not look to any other property or assets of Landlord or the
property or assets of any of the Exculpated Parties (defined below) in seeking
either to enforce Landlord's obligations under this Lease or to satisfy a
judgment for Landlord's failure to perform such obligations.

          (b) Notwithstanding anything contained in this Lease to the contrary.
Tenant shall look solely to Landlord to enforce Landlord's obligations hereunder
and no partner, shareholder, member, manager, director, officer, principal,
beneficial owner, employee or agent, directly and indirectly, of Landlord
(collectively, the "Exculpated Parties") shall be personally liable for the
performance of Landlord's obligations under this Lease. Tenant shall not seek
any damages against any of the Exculpated Parties.

          (c) Notwithstanding anything elsewhere in this Lease, except as
expressly provided in Article 28, under no circumstances shall either Landlord
or Tenant be liable to the other for any consequential damages or lost profits.

          (d) Whenever in this Lease it is provided that Landlord shall not be
liable to Tenant, the same shall be deemed and interpreted to mean and include
that Landlord shall not be liable for its negligence or that of its agents,
contractors, licensees, employees, servants or invitees, unless and only to the
extent that it is specifically and expressly stated that Landlord shall be
liable for such negligence.

          SECTION 34.2 (a) Wherever in this Lease Landlord's Approval is
required, if Landlord shall refuse such Approval, Tenant in no event shall be
entitled to make, nor shall Tenant make, any claim, and Tenant hereby waives any
claim, for money damages (nor shall Tenant claim any money damages by way of
set-off, counterclaim or defense) based upon any claim or assertion by Tenant
that Landlord unreasonably withheld or unreasonably delayed its Approval in any
one instance. Tenant's sole remedy as to such a claim or assertion shall be to
sue for specific performance.

          SECTION 34.3 In the event of any dispute between the parties to
enforce any obligation under this Lease, the prevailing party shall be entitled
to payment from the losing party of its costs and expenses incurred in such
enforcement, including reasonable attorneys' fees and disbursements.

ARTICLE 35 LANDLORD'S DEFAULT, TENANT'S REMEDIES, SELF-HELP

          SECTION 35.1 If Landlord shall fail to perform or observe any of the
material covenants contained in this Lease on Landlord's part to be performed or
observed or if Landlord shall breach any material warranty or representation
contained in this Lease; or shall fail to perform any of its material
obligations contained in this Lease and in any such event if Landlord shall fail
to cure same within five (5) days after receiving notice from Tenant thereof
(or, if the same cannot reasonably be cured within five (5) days, if Landlord
shall fail to promptly commence said cure within said five (5) days and
thereafter diligently prosecute said cure to completion), which notice shall
state in all capital letters that such notice is notice of default under this
Section 35.1 and that Landlord has five (5) days to cure or commence to cure
said default; then Tenant may in its sole discretion, and as its sole and
exclusive remedy, (except as expressly provided in Section 35.2) within ten (10)
days thereafter elect by notice to Landlord one of the following remedies:


                                       24

<PAGE>

          (a) if such matter relates exclusively to the Premises or to equipment
exclusively serving the Premises which is operated by Landlord, then Tenant may
perform such obligation(s) of Landlord in accordance with the provisions of this
Lease on behalf of and at the expense of Landlord (which expense must be
reasonable assuming that Landlord had performed such repair using its own staff
or contractors and in the ordinary course of business) and offset such expenses
against the Fixed Rent and Additional Rent;

          (b) bring an action against Landlord for the collection of any amounts
due to Tenant under this Lease for which Landlord is in default;

          (c) seek injunctive relief or specific performance for any other
covenant or agreement of Landlord; or

          (d) to take the credits provided under the SLA.

          SECTION 35.2 Supplementing the provisions of Section 35.1, if Landlord
shall fail to perform or observe any of the covenants contained in this Lease on
Landlord's part to be performed or observed or if Landlord shall materially
breach any warranty or representation contained in this Lease or shall fail to
perform any of its material obligations under this Agreement and provided that
any such event has actually interrupted Tenant's operation of its Mission
Critical Data Center in the Premises and if such matter relates exclusively to
the Premises or to equipment exclusively serving the Premises which is operated
by Landlord, then Tenant may in its sole discretion, as its sole and exclusive
remedy, may elect to either: (a) take the credits provided under the SLA or (b)
within one (1) Business Day after any such interruption elect by notice to
Landlord to perform such obligation(s) of Landlord in accordance with the
provisions of this Lease on behalf of and at the expense of Landlord (which
expense must be reasonable assuming that Landlord had performed such repair
using its own staff or contractors and in extraordinary course of business) and
offset such expenses against the Fixed Rent and Additional Rent; provided that
Tenant shall do so in accordance with all warranties, manufacturers
specifications, Building standard maintenance and repair procedures and similar
matters where Tenant has received notice thereof from Landlord.

ARTICLE 36 MISCELLANEOUS

          SECTION 36.1 The covenants of Landlord and Tenant in this Lease are
independent, and Fixed Rent and Additional Rent shall continue to be payable in
all events and under all circumstances and the obligations of Tenant hereunder
shall continue unaffected, unless the requirement to pay or perform the same
shall have been abated or suspended pursuant to an express provision of this
Lease.

          SECTION 36.2 (a) All of the Exhibits attached to this Lease are
incorporated in and made a part of this Lease, but, in the event of any
inconsistency between the terms and provisions of this Lease and the terms and
provisions of the Exhibits hereto, the terms and provisions of this Lease shall
control. This Lease may not be changed, modified, terminated or discharged, in
whole or in part, except by a writing, executed by the party, against whom
enforcement of the change, modification, termination or discharge is to be
sought. Wherever appropriate in this Lease, personal pronouns shall be deemed to
include the other genders and the singular to include the plural. The captions
hereof are inserted only as a matter of convenience and for reference and in no
way define, limit or describe the scope of this Lease nor the intent of any
provision thereof. All Article and Section references set forth in this Lease
shall, unless the context otherwise specifically requires, be deemed references
to the Articles and Sections of this Lease. Whenever the words "include",
"includes", or "including" are used in this Lease, they shall be deemed to be
followed by the words "without limitation".

          (b) This Lease shall be governed in all respects by the laws of the
Commonwealth of Massachusetts applicable to agreements executed in and to be
performed wholly within said State.

          (c) If any term, covenant, condition or provision of this Lease, or
the application thereof to any Person or circumstance, shall ever be held to be
invalid or unenforceable, then in each such event the remainder of this Lease or
the application of such term, covenant, condition or provision to any other
Person or any other circumstance (other than those as to which it shall be
invalid or unenforceable) shall not be thereby affected, and each term,
covenant, condition and provision hereof shall remain valid and enforceable to
the fullest extent permitted by Legal Requirements.

          (d) The covenants, conditions and agreements contained in this Lease
shall bind and inure to the benefit of Landlord and Tenant and their respective
legal representatives, successors, and, except as otherwise provided in this
Lease, their assigns. No Person is intended or shall be deemed to be a
third-party beneficiary of any of the terms of this Lease, it being intended
that this Lease be enforceable only by the Persons set forth in the preceding
sentence.

          SECTION 36.3 Except as expressly provided to the contrary in this
Lease, Tenant agrees that all disputes arising, directly or indirectly, out of
or relating to this Lease, and all actions to enforce this Lease, shall be dealt
with and adjudicated in the courts of the Commonwealth of Massachusetts or the
Federal courts sitting in Boston, Massachusetts; and for that purpose hereby
expressly and irrevocably submits itself to the jurisdiction of such courts.
Tenant hereby irrevocably appoints


                                       25

<PAGE>

the Secretary of the Commonwealth of Massachusetts as its authorized agent upon
which process may be served in any such action or proceeding.

          SECTION 36.4 Each of Landlord and Tenant agrees, in connection with
this Lease, not to disclose to any third party, without the other party's
Approval, (a) as to Tenant only, all financial and other material business or
legal terms of this Lease, and the Building, and (b) materials submitted from
one of them to the other and designated by the submitting party as confidential;
except only to the extent that (i) such information is a matter of public record
or is otherwise readily available to the real estate industry from other
sources, (ii) such disclosure is made on a comparably confidential basis to
either parties' attorneys, accountants, tax advisors or, as to disclosure by
Landlord, an existing or prospective purchaser, Mortgagee or Lessor of the
Building or the Property, on a need to know basis, or (iii) disclosure is
compelled by Legal Requirements or regulatory or judicial process, in which
latter case the party compelled shall first notify the other in writing and, if
requested by such party, shall use all commercially reasonable efforts to
preserve the confidentiality of the information in question to the greatest
possible extent.

          SECTION 36.5 Each of Landlord and Tenant hereby represents and
warrants to the other that it is duly organized, validly existing and in good
standing under the laws of the State of Delaware as to Landlord and the State of
Delaware as to Tenant, that is has the fully right and authority to enter into
this Lease, and that the execution, delivery and performance of this Lease by
it: (a) does not violate or conflict with any provisions of any instrument to
which it is a party or by which it is bound, and (b) constitutes its valid,
legal and binding obligation. In addition, each party represents that the
person(s) executing this Lease on its behalf is duly authorized to do so.

          SECTION 36.6 Tenant agrees not to record this Lease, but each party
hereto agrees, on the request of the other, to execute a so-called Notice of
Lease or short form lease in form recordable and complying with applicable law
and reasonably satisfactory to both Landlord's and Tenant's attorneys. In no
event shall such document set forth rent or other charges payable by Tenant
under this Lease; and any such document shall expressly state that it is
executed pursuant to the provisions contained in this Lease, and is not intended
to vary the terms and conditions of this Lease. In addition, Tenant shall
execute and acknowledge a release, in recordable form and complying with
applicable law and reasonably satisfactory to both Landlord's and Tenant's
attorneys, of such Notice of Lease. Such release shall be held by Landlord until
the Expiration Date at which time Landlord may, in its sole discretion, record
such release.


                                       26

<PAGE>

          SECTION 36.7 This Lease may be executed in counterparts or counterpart
signature pages, all of which when taken together shall constitute one Lease and
the signature page may be executed and delivered by facsimile.

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

          LANDLORD:                  SENTINEL PROPERTIES - BEDFORD, LLC

                                     By Sentinel Bedford Manager LLC


                                     By: /s/ Todd Aaron
                                         ---------------------------------------
                                     Name:   Todd Aaron
                                           -------------------------------------
                                     Title: Co-President
                                            ------------------------------------


          TENANT:                    ATHENAHEALTH, INC.


                                     By: /s/ Carl Byers
                                         ---------------------------------------
                                     Name:   Carl Byers
                                           -------------------------------------
                                     Title: CFO
                                            ------------------------------------

                                     Tenant's Federal Tax Identification Number:
                                     04-338-7530


                                       27
<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


                                    EXHIBIT A
                           FLOOR PLAN OF THE PREMISES

The floor plan which follows is intended solely to identify the general outline
of the Premises, and should not be used for any other purpose. All areas,
dimensions and locations are approximate, and any physical conditions indicated
may not exist as shown.


                                        *

                                       A-1

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.



                                    EXHIBIT B

                                   DEFINITIONS

          "Additional Rent" means any and all sums, other than Fixed Rent,
payable by Tenant to Landlord under this Lease.

          "Affiliate" means, with respect to any Person, any other Person that,
directly or indirectly, through one or more intermediaries, controls, is
controlled by, or is under common control with, such first Person.

          "Alterations" means alterations, installations, improvements,
additions or other physical changes, other than movable decorations, movable
fixtures, furniture and trade fixtures which can easily be removed without
material damage to the Building and other equipment not permanently affixed to
the Building and which can easily be removed without material damage to the
Building and includes Tenant Alterations unless the context requires otherwise.
Alterations shall include, without limitation, telephone, security system and
data wiring and cabling.


                                       *


          "Approval" or "Approved" means prior written approval, which approval
shall be in the sole discretion of the relevant Person unless otherwise
expressly stated.

          "Authorized Contacts" means such two (2) natural persons who are
agents or employees of Tenant, whom Tenant shall have designated or redesignated
(by notice to Landlord) from time to time as being Tenant's Authorized Contacts.
Any such designation or redesignation shall include, for each such Authorized
Contact, the Authorized Contact's name, office telephone, home telephone,
cellular telephone and facsimile numbers, and e-mail address where such
Authorized Contact may be reached for all relevant purposes under this Lease.
Tenant's initial Authorized Contacts as of the Commencement Date are identified
in Exhibit G hereto.

          "Base Rate" means the annual rate of interest publicly announced from
time to time by Citibank, N.A., New York, New York (or any successor thereto) as
its "base rate" (or such other term as may be issued by Citibank, N.A, from time
to time for the rate presently referred to as its base rate).

          "Broker" means Grubb & Ellis Company.

          "Building" means the improvements and equipment owned by Landlord at
the Property.

          "Business Days" means all days, excluding Saturdays, Sundays, and all
days observed by any or all of the Commonwealth of Massachusetts, the Federal
Government and the labor unions, if any, servicing the Building and/or the
Building as legal holidays.

          "Commencement Date" means the date of delivery of the relevant
Space(s) to Tenant pursuant to Section 2.3.

          "controls" or "controlled" (whether or not capitalized) means: (i) the
ownership, directly or indirectly, of more than fifty per cent (50%) of the
voting rights of a Person, or (ii) the possession, directly or indirectly, of
the power to direct or cause the direction of the management and policies of
such Person.

          "Core Building Systems" means the mechanical, electrical, heating,
ventilating, air conditioning, elevator, plumbing, sanitary, life-safety and
other service systems of the Building, but shall not include the portions of
such systems that constitute Dedicated Building Systems.

          "Data Center Use" means the use of environmentally-conditioned space
for the installation, operation and maintenance of communications, electronic
and optronic equipment and facilities relating to enterprise information
technology applications.


                                       B-1

<PAGE>

Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.

          "Dedicated Building Systems" means the mechanical, electrical,
heating, ventilating, air conditioning, elevator, plumbing, sanitary,
life-safety and other service systems of the Building that exist or are
installed in or upon the Premises or the Building and function for the exclusive
use of Tenant or serve only the Premises.

          "Default Rate" means a rate at all times equal to the greater of (a)
eighteen percent (18%) per annum, or (b) five (5) percentage points above the
Base Rate but in neither event higher than the maximum rate permitted by
applicable Legal Requirements.


                                       *


          "Expiration Date" means the Fixed Expiration Date or such earlier date
on which the Term sooner ends pursuant to any of the terms, conditions or
covenants of this Lease or pursuant to law.

          "Fixed Expiration Date" means the date which is one (1) day prior to
the twelfth (12th) anniversary of the Rent Commencement Date or if such day is
not the last day of a calendar month then such later date as is the last day of
the calendar month in which the anniversary of the Rent Commencement Date
occurs, as same may be extended by the exercise of one or more of the Extension
Options.

          "Fixed Rent" shall mean with respect to each Lease Year during the
Term of this Lease a monthly amount determined based on the Useable Square
Footage of the Premises which has been delivered to Tenant pursuant to Sections
1.1 and 2.3 as follows:

<TABLE>
<CAPTION>
Period Covered After Initial   Rent Per Useable   Premises Useable
     Commencement Date            Square Foot      Square Footage    Total Monthly Fixed Rent
----------------------------   ----------------   ----------------   ------------------------
<S>                            <C>                <C>                <C>
*                                      $*               *                        $*
*                                      $*               *                        $*
*                                      $*               *                        $*
*                                      $*               *                        $*
*                                      $*               *                        $*
</TABLE>

Thereafter, the Fixed Rent shall increase by * compounded cumulatively on
each anniversary of the Initial Commencement Date. Notwithstanding anything to
the contrary contained in this Lease: (a) the Fixed Rent shall increase on a per
Useable Square Foot basis on the dates set forth in the first column of
foregoing table applicable to the portions of the Premises that have been
delivered to Tenant pursuant to Section 2.3 utilizing the rent per square foot
figures in the foregoing table and the Useable Square Footage figures in the
foregoing table and (b) if delivery of any portion of the Premises to Tenant is
delayed beyond the dates set forth in the foregoing table then the Fixed Rent
adjustment as to such delayed portion of the Premises shall only apply as of the
date of delivery thereof to Tenant pursuant to Section 2.3. Fixed Rent shall be
paid on the first (1st) of each month in equal monthly installments and shall
also include any sums hereafter due pursuant to Section 1.2 and also Articles 29
or 30 and any other payments of sums in a recurring monthly amount.

          "Governmental Authority" means any of the United States of America,
the Commonwealth of Massachusetts, the Town of Bedford and/or the Town of
Billerica, any political subdivision thereof and any agency, department,
commission, board, bureau or instrumentality of any of the foregoing, now
existing or hereafter created, having jurisdiction over the Property or any
portion thereof or the curbs, sidewalks and areas adjacent thereto.

          "HVAC" means heat, ventilation and air-conditioning.

          "Lease Year" shall mean the one (1) year period commencing on the
Commencement Date and ending on the day before the first (1st) anniversary of
the Commencement Date and each succeeding period of one (1) year until the Fixed
Expiration Date.


                                       B-2

<PAGE>

          "Legal Requirements" means all present and future laws, rules, orders,
ordinances, regulations, statutes, requirements, codes, executive orders,
judgments, directives, guidance rules of common law, and any judicial
interpretations thereof, extraordinary as well as ordinary, of all Governmental
Authorities.

          "Lessor" means a lessor under a Superior Lease.

          "Managing Agent" means RC Property Management, LLC or its successor
from time to time as the managing agent of all or any part of the Building.

          "Mission Critical Data Center" shall mean a large scale, mission
critical data center for a Fortune 1000 type business with multiple locations,
it being understood that the operation of such data center is critical to the
operation of such business.

          "Mortgage" means any mortgage or trust indenture which may now or
hereafter encumber all or any part of the Building or any Superior Lease and the
leasehold interest created thereby, and all renewals, extensions, supplements,
amendments, modifications, consolidations and replacements thereof or thereto,
substitutions therefor, and advances made thereunder.

          "Mortgagee" means any mortgagee, trustee or other holder of a
Mortgage.

          "Original Tenant" means athenahealth, Inc., the original Tenant named
in this Lease.

          "Permitted Use" means the use of the Premises by Tenant as follows,
and for no other purpose: (a) the installation, operation and maintenance of
communication, electronic and optronic equipment and facilities relating to
various information technology applications which are customarily found in a
Mission Critical Data Center (the "Principal Permitted Use"); and (b) for other
incidental uses normally related thereto which are consistent with the use of
the Building as a Mission Critical Data Center and which are permitted by
applicable Legal Requirements.

          "Person" means any individual, corporation, partnership, limited
liability company, limited liability partnership, joint venture, estate, trust,
unincorporated association, business trust, tenancy-in-common or other entity,
or any Governmental Authority.

          "Premises" means the Initial Premises, Space 1, Space 2, Space 3 and 4
(each a "Space") as shown on the floor plan attached to this Lease as Exhibit A
and made a part hereof. In addition, wherever appropriate to the context, and in
any event including in the context of Tenant's obligations in Articles 2, 3, 5,
7, and 10, the term "Premises" shall be deemed to include any Tenant
Alterations, equipment, or installations located outside the Premises but on or
about the Property.

          "Property" means the Building, together with the land on which the
Building is located known as 55 Middlesex Turnpike, Bedford, Massachusetts.

          "Rules and Regulations" means: (a) the Occupant Handbook or any
similar manual in effect on the date hereof as same may reasonably be amended or
replaced from time to time, and (b) the rules and regulations of the Building as
adopted or amended by Landlord from time to time.

          "SLA" means the Service Level Agreement attached hereto as Exhibit F.

          "Substantial Completion" or "Substantially Completed" means, as to any
construction performed by any party in the Premises, that such work has been
completed in accordance with (a) the provisions of this Lease applicable
thereto, (b) the plans and specifications for such work, and (c) all applicable
Legal Requirements and applicable insurance requirements under this Lease,
except for minor details of construction, decoration and mechanical adjustments,
if any, the non-completion of which does not materially interfere with Tenant's
use of the Premises.

          "Superior Lease(s)" means any ground or underlying lease of the
Property or any part thereof hereafter made by Landlord (there being none on the
date hereof) and all renewals, extensions, supplements, amendments,
modifications and replacements thereof.

          "Tenant Alterations" means all Alterations which may be made by or on
behalf of Tenant prior to and during the Term.


                                      B-3

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


          "Tenant's Property" means Tenant's movable fixtures and movable
partitions, telephone and other office communications equipment, computer
systems, furniture, trade fixtures, furnishings and other items of personal
property which are easily removable without material damage to the Premises or
the Property.

          "Term" means the term of this Lease, which shall commence on the
Commencement Date and shall expire on the Expiration Date.


                                       *


                                      B-4

<PAGE>

                                    EXHIBIT C
                              INTENTIONALLY OMITTED


                                       C-1

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


                                    EXHIBIT D
                             REMAINING FIT OUT ITEMS


                                       *


                                       D-1

<PAGE>

Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.

                                    EXHIBIT E
         FORM OF SUBORDINATION, NON-DISTURBANCE AND ATTORNMENT AGREEMENT

TENANT:  ___________________

                                 SUBORDINATION,
                    NON-DISTURBANCE AND ATTORNMENT AGREEMENT

     THIS SUBORDINATION, NON-DISTURBANCE AND ATTORNMENT AGREEMENT (this
"AGREEMENT") is entered into between athenahealth, Inc. ("TENANT"), whose
address is 31 Arsenal street, Watertown, Massachusetts 02472, and SENTINEL
PROPERTIES - BEDFORD, LLC, a Delaware limited liability company ("LANDLORD"),
whose address is c/o Resolution Capital, LLC, 1270 Avenue of the Americas, Suite
204, New York, New York 10020.

                                   WITNESSETH:

     WHEREAS, Landlord is the owner in fee simple of the land and improvements
located at 55 Middlesex Turnpike, Bedford and Billerica, Massachusetts, as more
particularly described on EXHIBIT A attached hereto (the "PREMISES").

     WHEREAS, Landlord or its predecessor and Tenant have entered into a certain
Lease dated ________________, 200__ (as the same may have been or may hereafter
be amended, modified, restated, renewed or extended, the "LEASE"), leasing to
Tenant a portion of the Premises (the "TENANT PREMISES");

     WHEREAS, Lender is making a certain loan to Landlord in the principal
amount of up to * ($*) (the "LOAN"), which Loan shall be secured by, among other
things, a mortgage (as amended, as noted below, the "SECURITY INSTRUMENT") from
Landlord to Lender encumbering the Premises and certain other collateral
described in the Security Instrument;

     WHEREAS, Lender, Landlord and Tenant desire to confirm their understanding
with respect to the Lease and the Loan and the rights of Tenant and Lender
thereunder.

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained herein and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

          1. Subordination. Notwithstanding anything to the contrary set forth
in the Lease, Tenant hereby acknowledges that the Lease and the leasehold estate
created thereby and all of Tenant's rights thereunder are and shall remain
subordinate and subject to the Security Instrument and the liens thereof and all
advances and rights of Lender thereunder and to any and all renewals,
modifications, consolidations, replacements and extensions thereof. Without
affecting the foregoing subordination, Lender may, from time to time: (a)
extend, in whole or in part, by renewal or otherwise, the terms of payment or
performance of any obligation secured by the Security Instrument; (b) release,
surrender, exchange or modify any obligation secured by the Security Instrument,
or any security for such obligation; or (c) settle or compromise any claim with
respect to any obligation secured by the Security Instrument or against any
person who has given security for any such obligation.

          2. Non-Disturbance. If, at any time, Lender or any person or entity or
any of their successors or assigns who shall acquire the interest of Landlord
under the Lease through a foreclosure of the Security Instrument, the exercise
of the power of sale under the Security Instrument, a deed-in-lieu of
foreclosure, an assignment-in-lieu of foreclosure or otherwise (each, a "NEW
OWNER") shall succeed to the interests of Landlord under the Lease, so long as
(i) the Lease is then in full force and effect, (ii) Tenant complies with this
Agreement, and (iii) no default after the giving of any required notice, and
expiration of any applicable grace period, under the Lease (a "DEFAULT") on the
part of Tenant exists under the Lease, then the Lease shall continue in full
force and effect as a direct lease between the New Owner and Tenant, upon and
subject to all of the terms, covenants and conditions of the Lease, for the
balance of the term thereof (it being agreed that if the conditions in the
aforesaid clauses (i) through (iii) are not


                                       E-1

<PAGE>

met, then the New Owner shall not be obligated to recognize this Lease on the
terms and conditions contained herein and the Lease may be terminated by New
Owner and such termination may occur or be effected by Lender naming Tenant as a
defendant or subordinate party in a foreclosure action brought by Lender with
respect to the Loan). Tenant hereby agrees to attorn to and accept any such New
Owner as landlord under the Lease and to be bound by and perform all of the
obligations imposed by the Lease, and Lender, or any such New Owner, agrees that
it will not disturb the possession of Tenant and will be bound by all of the
obligations imposed on the Landlord by the Lease; provided, however, that any
New Owner shall not be:

               (a) liable for any act or omission of a prior landlord (including
Landlord) arising prior to the date upon which the New Owner shall succeed to
the interests of Landlord under the Lease; or

               (b) subject to any claims, offsets or defenses which Tenant might
have against any prior landlord (including Landlord) arising prior to the date
upon which the New Owner shall succeed to the interests of Landlord under the
Lease; or

               (c) bound by any rent or additional rent which Tenant might have
paid in advance to any prior landlord (including Landlord) for a period in
excess of one (1) month or by any security deposit or other prepaid charge which
Tenant might have paid in advance to any prior landlord (including Landlord),
except to the extent that such New Owner actually comes into exclusive
possession of the same; or

               (d) bound by any assignment (except as permitted by the Lease),
surrender, release, waiver, cancellation, amendment or modification of the Lease
made without the written consent of Lender; or

               (e) responsible for the making of any improvements to the
Premises or repairs in or to the Premises including, without limitation, in the
case of damage or destruction of the Premises or any part thereof due to fire or
other casualty or by reason of condemnation unless such New Owner shall be
obligated under the Lease to make such repairs; or

               (f) obligated to make any payment to Tenant (except for the
timely return of any security deposit actually received by such New Owner)
arising prior to the date upon which the New Owner shall succeed to the
interests of Landlord under the Lease.

               3. Cure by Lender of Landlord Defaults. Tenant hereby agrees that
from and after the date hereof, in the event of any act or omission by Landlord
which would give Tenant the right, either immediately or after the lapse of
time, to terminate or cancel the Lease or to claim a partial or total eviction,
or to abate or reduce rent (none of the foregoing, however, being deemed to
create or infer any such right in Tenant), Tenant will not exercise any such
right until it has given written notice of such act or omission to Lender, and
Lender has failed, within thirty (30) days after receipt of such notice by
Lender, to commence to cure such act or omission and to thereafter diligently
prosecute such cure to completion; provided that in the event Lender cannot
commence such cure without possession of the Premises, Tenant will not exercise
any such right if Lender commences judicial or non-judicial proceedings to
obtain possession within such period and thereafter diligently prosecutes such
efforts and cure to completion; further, Tenant shall not, as to Lender, require
cure of any such act or omission which is not susceptible to cure by Lender. The
foregoing shall not be deemed to prevent or delay Tenant from, to the extent
expressly permitted or provided for under the Lease and in accordance with the
procedures set forth in the Lease, exercising any rights of self-help to make
repairs to the Tenant Premises or to appurtenant common areas or to seek
injunctive relief to compel Landlord or any other party to make repairs to the
Tenant Premises or to appurtenant common areas or to cease to interfere with
Tenant use and occupancy of the Tenant Premises.

          4. Payments to Lender and Exculpation of Tenant. Tenant is hereby
notified that the Lease and the rent and all other sums due thereunder have been
assigned to Lender as security for the Loan. In the event that Lender or any
future party to whom Lender may assign the Security Instrument directs that
Tenant pay its rent and all other sums due under the Lease to Lender or to such
assignee, Tenant shall honor such direction without inquiry and pay its rent and
all other sums due under the Lease in accordance with such notice. Landlord
agrees that Tenant shall have the right to rely on any such notice from Lender
or any such assignee without incurring any obligation or liability to Landlord,
and Tenant is hereby instructed to disregard any notice to the contrary received
from Landlord or any third party.


                                      E-2

<PAGE>

          5. Limitation of Liability. Lender shall not, either by virtue of the
Security Instrument, the Assignment of Leases or this Agreement, be or become a
mortgagee-in-possession or be or become subject to any liability or obligation
under the Lease or otherwise unless and until Lender shall have acquired the
interest of Landlord in the Premises, by foreclosure or otherwise, and then such
liability or obligation of Lender under the Lease shall extend only to those
liabilities or obligations accruing subsequent to the date that Lender has
acquired the interest of Landlord in the Premises as modified by the terms of
this Agreement. In addition, upon such acquisition, Lender shall have no
obligation, nor incur any liability, beyond Lender's then equity interest, if
any, in the Premises. Furthermore, in the event of the assignment or transfer of
the interest of Lender under this Agreement, all obligations and liabilities of
Lender under this Agreement shall terminate and, thereupon, all such obligations
and liabilities shall be the sole responsibility of the party to whom Lender's
interest is assigned or transferred.

          6. Notice. Any notice, demand, statement, request, consent or other
communication made hereunder shall be in writing and delivered (i) personally,
(ii) mailed by certified or registered mail, postage prepaid, return receipt
requested or (iii) by depositing the same with a reputable private courier
service, postage prepaid, for next business day delivery, to the parties at
their addresses first set forth above and shall be deemed given when delivered
or, if delivery is attempted and refused, when delivery is tendered. A copy of
any notice given by Tenant to Lender or by Lender to Tenant shall be given at
the same time and in the same manner to Landlord. A copy of any notice given
Tenant shall be given at the same time and in the same manner
to:____________________________________________________________________. A copy
of any notice given Landlord shall be given at the same time and in the same
manner to: Jeffrey A. Moerdler, Mintz Levin Cohn Ferris Glovsky & Popeo, P.C.,
666 Third Avenue, New York, New York 10017. Rejection or other refusal to accept
or the inability to deliver because of changed address of which no notice was
given as herein required shall be deemed to be receipt of the notice, demand or
request sent. By giving to the other parties thereto at least fifteen (15) days'
prior written notice hereof in accordance with the provisions hereof, the
parties hereto shall have the right from time to time to change their respective
addresses to any other address within the United States of America. Tenant
agrees to send a copy of any notice or statement under the Lease to Lender at
the same time such notice or statement is sent to Landlord.

          7. Miscellaneous.

               (a) In the event of any conflict or inconsistency between the
provisions of this Agreement and the Lease, the provisions of this Agreement
shall govern; provided, however, that the foregoing shall in no way diminish
Landlord's rights or Tenant's liability under the Lease. Lender's enforcement of
any provisions of this Agreement or the Security Instrument shall not entitle
Tenant to claim any interference with the contractual relations between Landlord
or Tenant or give rise to any claim or defense against Lender with respect to
the enforcement of such provisions.

               (b) Tenant agrees that this Agreement satisfies any condition or
requirement in the Lease relating to the granting of a non-disturbance
agreement.

               (c) Tenant agrees that it will not without Lender's approval
subordinate the Lease to the lien of any mortgage or deed of trust given by
Landlord with respect to the Premises, other than the Security Instrument for so
long as the Security Instrument shall remain a lien on the Premises.

               (d) This Agreement shall inure to the benefit of the parties
hereto and their respective successors and assigns; provided, however, that the
interest of Tenant under this Agreement may not be assigned or transferred,
except as Tenant shall have the specific right to assign its interest in the
Lease, without the prior written consent of Lender (to be given or withheld
according to the same standard of discretion applicable to the Landlord's
consent to the corresponding transfer of Tenant's interest under the Lease).

               (e) The captions appearing under the paragraph number
designations of this Agreement are for convenience only and are not a part of
this Agreement and do not in any way limit or amplify the terms and provisions
of this Agreement.


                                      E-3

<PAGE>

               (f) If any portion or portions of this Agreement shall be held
invalid or inoperative, then all of the remaining portions shall remain in full
force and effect, and, so far as is reasonable and possible, effect shall be
given to the intent manifested by the portion or portions held to be invalid or
inoperative.

               (g) This Agreement shall be governed by and construed in
accordance with the laws of the Commonwealth of Massachusetts.

               (h) This Agreement may be executed in any number of separate
counterparts, each of which shall be deemed an original, but all of which,
collectively and separately, shall constitute one and the same agreement.

               (i) This Agreement cannot be altered, modified, amended, waived,
extended, changed, discharged or terminated orally or by any act on the part of
Tenant, Landlord or Lender, but only by an agreement in writing signed by the
party against whom enforcement of any alteration, modified, amendment, waiver,
extension, change, discharge or termination is sought.

                            [SIGNATURES ON NEXT PAGE]


                                      E-4

<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the
dates set forth adjacent to their signatures below to be effective as of the
date of the Security Instrument.

LANDLORD:                               SENTINEL PROPERTIES - BEDFORD, LLC


                                        By Sentinel Bedford Manager LLC


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Title:
                                               ---------------------------------


TENANT:                                 ATHENAHEALTH, INC.


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Title:
                                               ---------------------------------

                                        Tenant's Federal Tax Identification
                                        Number: 04-338-7530

WHEN RECORDED, RETURN TO:

PAUL, HASTINGS, JANOFSKY & WALKER LLP
75 EAST 55TH STREET
NEW YORK, NEW YORK 10022

ATTN.: STEVEN KOCH, ESQ.


                                      E-5

<PAGE>

STATE OF ______________    )

                           )  SS

COUNTY OF ____________     )

On the ______ day of ________, 200__ before me, the undersigned, a notary public
in and for said state, personally appeared ______________________________,
personally known to me or proved to me on the basis of satisfactory evidence to
be the individual(s) whose name(s) is (are) subscribed to the within instrument
and acknowledged to me that he/she/they executed the same in his/her/their
capacity(ies), and that by his/her/their signature(s) on the instrument, the
individual(s), or the person upon behalf of which the individual(s) acted,
executed the instrument.


                                        ----------------------------------------
                                        Notary Public

                                        [notarial seal]

STATE OF ______________    )

                           )  SS

COUNTY OF ____________     )

On the ______ day of ________, 200__ before me, the undersigned, a notary public
in and for said state, personally appeared ______________________________,
personally known to me or proved to me on the basis of satisfactory evidence to
be the individual(s) whose name(s) is (are) subscribed to the within instrument
and acknowledged to me that he/she/they executed the same in his/her/their
capacity(ies), and that by his/her/their signature(s) on the instrument, the
individual(s), or the person upon behalf of which the individual(s) acted,
executed the instrument.


                                        ----------------------------------------
                                        Notary Public

                                        [notarial seal]


                                      E-6

<PAGE>

STATE OF ______________    )

                           )  SS

COUNTY OF ____________     )

On the ______ day of ______________, 200__ before me, the undersigned, a notary
public in and for said state, personally appeared ____________________________,
personally known to me or proved to me on the basis of satisfactory evidence to
be the individual(s) whose name(s) is (are) subscribed to the within instrument
and acknowledged to me that he/she/they executed the same in his/her/their
capacity(ies), and that by his/her/their signature(s) on the instrument, the
individual(s), or the person upon behalf of which the individual(s) acted,
executed the instrument.

                                        ----------------------------------------
                                        Notary Public

                                        [notarial seal]

[suggested Mass. notary form]

                    COMMONWEALTH / STATE OF _________________

___________, ss.                                               ___________, 2005

     On this ____ day of __________, 200__, before me, the undersigned notary
public, personally appeared __________________, proved to me through
satisfactory evidence of identification, which were __________________, to be
the person whose name is signed on the preceding or attached document, and
acknowledged to me that he signed it voluntarily for its stated purpose, as
________________ of _______________, a ___________________, and acknowledged the
foregoing instrument to be his free act and deed and the free act and deed of
said ____________________, before me.


                                        ----------------------------------------
                                        Notary Public:

                                        My Commission Expires:


                                      E-7

<PAGE>

                                    EXHIBIT A

                             DESCRIPTION OF PREMISES

                                [To be inserted]


                                       E-1

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


                                    EXHIBIT F
                             SERVICE LEVEL AGREEMENT


                                       *


                                      F-1

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


                                       *


                                        2

<PAGE>
Confidential Materials omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote omissions.


                                    EXHIBIT G
                      TENANT'S INITIAL AUTHORIZED CONTACTS

<TABLE>
<CAPTION>
Information                    Contact #1              Contact #2
-----------              ---------------------   ----------------------
<S>                      <C>                     <C>
1.  Name                 *                        *

2.  Office Telephone     *                        *

3.  Home Telephone       *                        *

4.  Cellular Telephone   *                        *

5.  Facsimile Number     *                        *

6.  E-mail Address       *                        *
</TABLE>


                                       G-1