Document:

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                                                                   Exhibit 10.39

          INDENTURE OF LEASE made as of this     day of March, 2000, between 622
BUILDING COMPANY LLC, a New York limited liability company, having an office at
750 Lexington Avenue, New York, New York 10022 ("Landlord") and CMGI  Inc., a
Delaware corporation having an office at 100 Brickstone Square, Andover,
Massachusetts 01810 ("Tenant").

                             W I T N E S S E T H :

                                   ARTICLE 1

                                Premises; Term

          Landlord hereby leases to Tenant and Tenant hereby hires from Landlord
the following space ("Demised Premises"): the entire 9/th/ and 11/th/ and part
of the 10th floors as shown crosshatched on the floor plan (Schedule A) attached
hereto, in the office building known as and by the street number 622 Third
Avenue, in the Borough of Manhattan, City and State of New York ("Building"),
upon and subject to the terms, covenants and conditions hereafter set forth.

          TO HAVE AND TO HOLD the Demised Premises unto Tenant for a term
commencing on March 15, 2000 (the "Commencement Date") (subject to Section 2.01)
and ending on August 31, 2007 (the "Expiration Date"), or on such earlier date
upon which said term may expire or terminate pursuant to the conditions of this
Lease or pursuant to law.

          IT IS MUTUALLY COVENANTED AND AGREED between Landlord and Tenant as
follows:

                                   ARTICLE 2

                             Commencement of Term

          Section 2.01.  The term of this Lease, for which the Demised Premises
are hereby leased, shall commence on the Commencement Date, and the Landlord
shall deliver possession of the Demised Premises on the Commencement Date and
deliver a countersigned original of this Lease on or before such date.  Delivery
of possession of the Demised Premises includes delivery of keys and reasonable
access to and from all portions of the Demised Premises.

          Section 2.02.     Tenant has fully inspected the Demised Premises, is
familiar with the condition thereof and agrees to accept possession of the same
on the Commencement Date.  Landlord shall not be required to do any work therein
to make the same suitable for the operation of Tenant's business.

                                       1
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          Section 2.03.  Promptly after the Commencement Date, Landlord and
Tenant shall execute a statement in recordable form confirming the agreed upon
Commencement and Expiration Dates of this Lease, in accordance with the
foregoing provisions.

                                   ARTICLE 3

                                     Rent

          Section 3.01.  Tenant shall pay as rent for the Demised Premises, the
following:

               (a) a fixed minimum rent (the "minimum rent") at the annual rate
     of $3,375,000.00 per annum (or $281,250.00 per month), provided if the
     Commencement Date is not the first day of a month, then the minimum rent
     for such month shall be prorated; and

               (b) all other sums and charges required to be paid by Tenant
     under the terms of this Lease (including without limitation, the payments
     required to be made under Article 22), which shall be deemed to be and are
     sometimes referred to hereafter as additional rent.

          Section 3.02.  Notwithstanding the provisions of Section 3.01 hereof
and provided Tenant is not then in default under any of the provisions of this
Lease on its part to be performed, Tenant shall be entitled to an abatement of
the minimum rent only as follows: the amount of $281,250.00 for each of the
1/st/, 2/nd/, 3/rd/, 37/th/ and 49/th/ full months of the term succeeding the
Commencement Date. Tenant acknowledges that the consideration for the aforesaid
abatement of minimum rent is Tenant's agreement to perform all of the terms,
covenants and conditions of this Lease on its part to be performed. Tenant shall
be required to pay additional rent from and after the Commencement Date.

          Section 3.03.  The minimum rent shall be payable in equal monthly
installments in advance on the first day of each and every month during the term
of this Lease, except that the amount of $281,250.00 shall be paid upon the
execution of this Lease and applied to the payment of minimum rent for the
fourth (4th) full month of the term.

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          Landlord and Tenant agree that Tenant shall pay minimum rent,
additional rent and other amounts now due or hereafter to become due to the
Landlord or its agents as provided for in this Lease, (as and when due) directly
to the following lock-box account:

                    622 Building Company LLC
                    P.O. Box 41007
                    Newark, New Jersey 07101-8700

All rent checks shall be made payable to 622 Building Company LLC.

          Section 3.04.  Tenant shall pay the minimum rent and additional rent
in lawful money of the United States which shall be legal tender for the payment
of all debts, public and private, at the time of payment.

          Section 3.05.  The minimum rent and additional rent shall be payable
by Tenant without any set-off, abatement or deduction whatsoever and without
notice or demand, except as otherwise expressly provided herein.

                                   ARTICLE 4

                                      Use

          Section 4.01.  Tenant shall use and occupy the Demised Premises for
administrative, executive and general office purposes only, including a data
center and computer room.

          Section 4.02.  Notwithstanding the provisions of Section 4.01, Tenant
shall not use or allow the use of the Demised Premises or any part thereof (1)
for the cooking and/or sale of food, except that Tenant may have a coffee maker
and warm foods through a microwave; (2) for storage for sale of any alcoholic
beverage in the Demised Premises; (3) for the storage and/or sale of any product
or material from the Demised Premises; (4) for manufacturing or printing
purposes; (5) for the conduct of a school or training facility or similar type
of business which results in the presence of the general public in the Demised
Premises, except that Tenant may have training classes for its personnel
incidental to its business; (6) for the conduct of the business of an employment
agency or personnel agency; (7) for the conduct of any public auction or public
exhibition; (8) for occupancy by a foreign, United States, state, municipal or
other governmental or quasi-governmental body, agency or department or any
authority or other entity which is affiliated therewith or controlled thereby
and which has diplomatic or sovereign immunity or the like with respect to a
commercial lease; (9) for messenger or delivery service (excluding Tenant's own
employees or outside services); (10) as a public stenographer or typist; (11) as
a telephone or telegraph agency, except that Tenant as an incident to its
business may have audio visual and closed circuit television facilities and
other types of telecommunication equipment; (12) as a company engaged in the
business of renting office(s) or desk space in the Demised Premises; (13) as
medical offices or a laboratory; (14)

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as a travel agency; (15) as a dating service; (16) as a restaurant; (17) as a
night club, discotheque, arcade or like kind establishments; (18) as a public or
quasi-public health facility, radiation treatment facility, methadone clinic or
other drug related clinic, abortion clinic, or for any practice conducted in or
through the format of a clinic; (19) as a pawn shop; (20) as an off-track
betting parlor; (21) as a homeless shelter, soup kitchen or similar use; (22)
for the sale or display or pornographic products or services; (23) for the use
or storage of flammable liquids or chemicals (unless incidental to a permitted
use); (24) as a funeral parlor; (25) for the sale or grooming of pets; or (26)
for any form of spiritualist services, such a fortune telling or reading.
Furthermore, the Demised Premises shall not be used for any purpose that would,
in Landlord's reasonable judgment, create unreasonable or excessive elevator or
floor loads, impair or interfere with any of the Building operations or the
proper and economic heating, air-conditioning, cleaning or any other services of
the Building, interfere with the use of the other areas of the Building by any
other tenants, or impair the appearance of the Building. Neither Tenant nor any
person within Tenant's control shall use, generate, store, treat and/or dispose
of any Hazardous Materials (as hereinafter defined) in, on, under or about the
Demised Premises, except for small quantities customarily used in offices and in
compliance with all applicable laws.

          Section 4.03.  If any governmental license or permit, other than a
Certificate of Occupancy or any license or permit required for the proper and
lawful conduct of Tenant's business in the Demised Premises, or any part
thereof, and if failure to secure such license or permit would in any way affect
Landlord, Tenant, at its expense, shall duly procure and thereafter maintain
such license or permit and submit the same for inspection by Landlord.  Tenant
shall at all times comply with the terms and conditions of each such license or
permit.

          Section 4.04.  Tenant shall not at any time use or occupy, or permit
anyone to use or occupy, the Demised Premises, or do or permit anything to be
done in the Demised Premises, in violation of the Certificate of Occupancy, for
the Demised Premises or for the Building, and will not permit or cause any act
to be done or any condition to exist on the Demised Premises which may be
dangerous unless safeguarded as required by law, or which in law constitutes a
nuisance, public or private, or which may make void or voidable any insurance
then in force covering the Building and building equipment.

          Section 4.05.  Landlord represents that the existing Certificate of
Occupancy permits the use of the Demised Premises for the purposes set forth in
Section 4.01, and that Landlord shall not change the Certificate of Occupancy to
prohibit such uses.

                                   ARTICLE 5

                             Alterations, Fixtures

          Section 5.01.  Tenant, without Landlord's prior consent, shall make no
structural alterations, installations, additions, or improvements in or to the
Demised Premises ("work") including, but not limited to, an air-conditioning or
cooling system, or any unit or part

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thereof or other apparatus of like or other nature, railings, mezzanine floors,
galleries and the like. However, Tenant may make non-structural interior work,
subject to Landlord's prior written consent which shall not be unreasonably
withheld or delayed. Notwithstanding the foregoing, Tenant, without Landlord's
consent but subject to Landlord's approval of contractors, may make non-
structural interior work which does not affect the structural integrity of the
Building or the Building systems, does not affect the other tenants in the
Building, does not violate any mortgage, does not cost more than $50,000 in the
aggregate during any twelve (12) month period, and Tenant has given not less
than ten (10) days prior notice thereof. With respect to any work requiring
Landlord's approval and performance by any contractor other than Landlord,
Tenant shall pay to Landlord ten (10%) percent of the cost of such work for
supervision, coordination and other expenses incurred by Landlord in connection
therewith. However, such ten (10%) percent charge shall not apply to Tenant's
initial work in the Demised Premises nor does it apply to painting,
wallcovering, carpeting or furnishings. Tenant acknowledges that the ICIP
Program (as hereinafter defined) may impose requirements with respect to the
hiring and training practices, among other matters, of contractors and
subcontractors engaged to perform certain work in the Building for Tenant
(collectively, herein called "Tenant's Contractors"). To the extent required by
law, Tenant shall use Tenant's Contractors (subject to Landlord's approval )
that qualify under the applicable requirements of the ICIP Program for the
performance of Tenant's initial work and any subsequent alterations to the
Demised Premises and Tenant will require Tenant's Contractors to comply with the
provisions of the ICIP Program. If Landlord is notified of any violation of the
ICIP Program by Tenant's Contractors (to the extent such contractors are
required by law to comply with the ICIP Program) Landlord shall promptly advise
Tenant, and Tenant shall take all necessary actions to cure such violations.
Workers' compensation and public liability insurance and property damage
insurance, all in amounts and with companies and/or forms reasonably
satisfactory to Landlord, shall be provided and at all times maintained by
Tenant's contractors engaged in the performance of the work, and before
proceeding with the work, certificates of such insurance shall be furnished to
Landlord. If consented to by Landlord, all such work shall be done at Tenant's
sole expense and in full compliance with all governmental authorities having
jurisdiction thereover. Upon completion of such work, Tenant shall deliver to
Landlord full scale "as built" plans for the same. Landlord upon request of
Tenant, will waive its right to any lien upon Tenant's trade fixtures and
equipment, in such form as shall be reasonably acceptable to Landlord. All work
affixed to the realty or if not so affixed but for which Tenant shall have
received a credit, shall become the property of Landlord, subject to Tenant's
right to replace same during the term hereof with items of equal quality class
and value, and shall remain upon, and be surrendered with, the Demised Premises
as a part thereof at the end of the term or any renewal or extension term, as
the case may be, without allowance to Tenant or charge to Landlord, unless
Landlord elects otherwise on notice to Tenant given at the time that Landlord
has consented to the work. However, if Landlord shall elect at the time Tenant
requests consent to any work, otherwise, Tenant at Tenant's expense, at or prior
to any termination of this Lease, shall remove all such work or such portion
thereof as Landlord shall elect and Tenant shall restore the Demised Premises to
its original condition, reasonable wear and tear excepted, at Tenant's expense.
However, Tenant shall not be obligated to remove its initial work in the Demised
Premises. If any Building facilities or services, including but not

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limited to air-conditioning and ventilating equipment installed by Landlord, are
adversely affected or damaged by reason of the work by Tenant, Tenant, at its
expense, shall repair such damage to the extent such damage has been caused by
Tenant's work and shall correct the work so as to prevent any further damage or
adverse effect on such facilities or services.

          Section 5.02.  Prior to commencing any work pursuant to the provisions
of Section 5.01, Tenant shall furnish to Landlord:

               (a) Plans and specifications for the work to be done.  However,
     if Landlord fails to respond to Tenant's request for Landlord's consent to
     the work within ten (10) business days after its receipt of such request
     together with all required information, then Landlord shall be deemed to
     have consented thereto.

               (b) Copies of all governmental permits and authorizations which
     may be required in connection with such work.

               (c) A certificate evidencing that Tenant (or Tenant's contractor)
     has procured workers' compensation insurance covering all persons employed
     in connection with the work who might assert claims for death or bodily
     injury against Landlord, Tenant, any mortgagee or the Building.

               (d) Such additional personal injury and property damage insurance
     (over and above the insurance required to be carried by Tenant pursuant to
     the provisions of Section 9.03) as Landlord may reasonably require because
     of the nature of the work to be done by Tenant.

               (e) With respect to Tenant's work, other than Tenant's initial
     work, exceeding the cost of $50,000, a bond or other security satisfactory
     to Landlord, in the amount of one hundred ten (110%) percent of the
     aggregate cost of the work, to insure completion of such work.

          Section 5.03.  Where furnished by or at the expense of Tenant (except
the replacement of an item theretofore furnished and paid for by Landlord or for
which Tenant has received a credit), all movable property, furniture,
furnishings, roller files, equipment and trade fixtures ("personalty") other
than those affixed to the realty in such manner as to cause material damage upon
its removal, shall remain the property of and shall be removed by Tenant on or
prior to any termination or expiration of this Lease, and, in the case of damage
by reason of such removal, Tenant, at Tenant's expense, promptly shall repair
the damage.  If Tenant does not remove any such personalty, Landlord, after two
(2) business days notice to Tenant, at its election, (a) may cause the
personalty to be removed and placed in storage at Tenant's expense or (b) may
treat the personalty as abandoned and may dispose of the personalty as it sees
fit without accounting to Tenant for any proceeds realized upon such disposal.

          Section 5.04.  Tenant agrees that the exercise of its rights pursuant
to the

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provisions of this Article 5 shall not be done in a manner which would create
any work stoppage, picketing, labor disruption or dispute or violate Landlord's
union contracts affecting the Building or interfere with the business of
Landlord or any Tenant or occupant of the Building. In the event of the
occurrence of any condition described above arising from the exercise by Tenant
of its right pursuant to the provisions of this Article 5, Tenant shall,
immediately upon notice from Landlord, cease the manner of exercise of such
right giving rise to such condition. In the event Tenant fails to cease such
manner of exercise of its rights as aforesaid, Landlord, in addition to any
rights available to it under this Lease and pursuant to law, shall have the
right to injunction. With respect to Tenant's work, Tenant shall make all
arrangements for, and pay all expenses incurred in connection with, use of the
freight elevators servicing the Demised Premises during those hours other than
as provided in Section 21.01(a) in accordance with Landlord's customary charges
therefor.

                                   ARTICLE 6

                                    Repairs

          Section 6.01.  Except as provided in Articles 10 and 14, Tenant shall
take good care of the Demised Premises and the fixtures wholly contained therein
and all portions of the HVAC, mechanical, plumbing and electrical systems wholly
contained within and exclusively serving the Demised Premises, and at its sole
cost and expense make all repairs thereto as and when needed to preserve them in
good working order and condition.   All damage or injury to the Demised Premises
or the Building or to any building equipment or systems caused by Tenant moving
property in or out of the Building or by installation or removal of personalty
or resulting from negligence or conduct of Tenant, its employees, agents,
contractors, customers, invitees and visitors, shall be repaired, promptly by
Tenant at Tenant's expense, and whether or not involving structural changes or
alterations, to the satisfaction of Landlord.  All repairs shall include
replacements or substitutions where necessary and shall be at least equal to
the quality, class and value of the property repaired, replaced or substituted
and shall be done in a good and workmanlike manner.

          Section 6.02.  Landlord, at its expense, shall maintain and make all
repairs and replacements, structural and otherwise, to the exterior and public
portions of the Building, the Building systems up to its connection with the
Demised Premises, and to the Demised Premises, unless Tenant is required to make
them under the provisions of Section 6.01 or unless required as a result of the
performance or existence of alterations performed by Tenant or on Tenant's
behalf, in which event Tenant, at its expense, shall perform such maintenance,
repairs or replacements.  Tenant shall notify Landlord of the necessity for any
repairs for which Landlord may be responsible in the Demised Premises under the
provisions of this Section.  Landlord shall have no liability to Tenant by
reason of any inconvenience, annoyance, interruption or injury to business
arising from Landlord's making any repairs or changes which Landlord is required
or permitted by this Lease, or required by law, to make in or to any portion of
the Building or the Demised Premises, or in or to the fixtures, equipment or
appurtenances of the Building or the Demised Premises.  Notwithstanding the
foregoing,

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Landlord shall use reasonable efforts to make such repairs or changes in a
manner to minimize its interference with the normal conduct of Tenant's
business, provided Landlord shall not be required to employ overtime or premium
labor.

          Section 6.03.  Tenant shall not store or place any materials or other
obstructions in the lobby or other public portions of the Building, or on the
sidewalk abutting the Building.

                                   ARTICLE 7

                               Floor Load; Noise

          Section 7.01.  Tenant shall not place a load upon any floor of the
Demised Premises which exceeds the load per square foot which such floor was
designed to carry (50 lbs. live per square foot).

          Section 7.02.  Business machines and mechanical equipment belonging to
Tenant which cause noise, vibration or any other nuisance that may be
transmitted to the structure or other portions of the Building or to the Demised
Premises, to such a degree as to be objectionable to Landlord or which interfere
with the use or enjoyment by other tenants of their premises or the public
portions of the Building, shall be placed and maintained by Tenant, at Tenant's
expense, in settings of cork, rubber or spring type vibration eliminators
sufficient to eliminate such objectionable or interfering noise or vibration.

                                   ARTICLE 8

             Laws, Ordinances, Requirements of Public Authorities

          Section 8.01.  (a)  Subject to the provisions of this Article 8,
     Tenant, at its expense, shall comply with all laws, orders, ordinances,
     rules and regulations and directions of Federal, State, County and
     Municipal authorities and departments thereof having jurisdiction over the
     Demised Premises and the Building, including but not limited to the
     Americans With Disabilities Act ("Governmental Requirements"), referable to
     Tenant or the Demised Premises, arising by reason of Tenant's particular
     manner of use of the Demised Premises (other than in contradistinction
     merely for the office uses permitted in Section 4.01) or any installations
     made therein by or at Tenant's request, or any default by Tenant under this
     Lease.

               (b) Except as otherwise provided herein, Tenant covenants and
     agrees that Tenant shall, at Tenant's sole cost and expense, comply at all
     times with all Governmental Requirements governing the use, generation,
     storage, treatment and/or disposal of any "Hazardous Materials" (which term
     shall mean any biologically or chemically active or other toxic or
     hazardous wastes, pollutants or substances, including, without limitation,
     asbestos, PCBs,

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     petroleum products and by-products, substances defined or listed as
     "hazardous substances" or "toxic substances" or similarly identified in or
     pursuant to the Comprehensive Environmental Response, Compensation and
     Liability Act, 42 U.S.C. (S) 9601 et seq., and as hazardous wastes under
     the Resource Conservation and Recovery Act, 42 U.S.C. (S) 6010 et seq., any
     chemical substance or mixture regulated under the Toxic Substance Control
     Act of 1976, as amended, 15 U.S.C. (S) 2601 et seq., any "toxic pollutant"
     under the Clean Water Act, 33 U.S.C. (S) 466 et seq., as amended, any
     hazardous air pollutant under the Clean Air Act, 42 U.S.C. (S) 7401 et
     seq., hazardous materials identified in or pursuant to the Hazardous
     Materials Transportation Act, 49 U.S.C. (S) 1802 et seq., and any hazardous
     or toxic substances or pollutant regulated under any other Governmental
     Requirements). Tenant shall agree to execute, from time to time, at
     Landlord's request, affidavits, representations and the like concerning
     Tenant's best knowledge and belief regarding the presence of Hazardous
     Materials in, on, under or about the Demised Premises, the Building or the
     Land. Tenant shall indemnify and hold harmless Landlord, its partners,
     officers, shareholders, members, directors and employees, Overlandlord and
     any mortgagee (collectively, the "Indemnitees"), from and against any loss,
     cost, damage, liability or expense (including attorneys' fees and
     disbursements) arising by reason of any cleanup, removal, remediation,
     detoxification action or any other activity required or recommended of any
     Indemnitees by any government authority by reason of the presence in or
     about the Land, the Building or the Demised Premises of any Hazardous
     Materials, as a result of or in connection with the act or omission of
     Tenant or any person or entity within Tenant's control or the breach of
     this Lease by Tenant or any person or entity within Tenant's control. The
     foregoing covenants and indemnity shall survive the expiration of any
     termination of this Lease. Tenant, at its own cost and expense, may
     contest, in any manner permitted by Governmental Requirements (including
     appeals to a court, governmental department or authority having
     jurisdiction), the validity or the enforcement of any Government
     Requirements which Tenant is required to comply, and may defer compliance,
     provided that (i) such non-compliance shall not subject Landlord to
     criminal prosecution or subject the Land and/or Building to sale or any
     lien, unless Tenant posts a bond to remove such lien, (ii) Tenant shall
     indemnify Landlord against any cost, damage or injury from such non-
     compliance, and if any mortgagee shall require, Tenant shall deliver a
     surety bond by a surety company approved by such mortgagee and Landlord
     with respect to such indemnity, and (iii) Tenant shall promptly, diligently
     and continuously prosecute such contest. Landlord, at no expense to
     Landlord, shall cooperate with Tenant and execute any required documents,
     provided Landlord is reasonably satisfied that the facts set forth in such
     documents are accurate.

               (c) Landlord, at its expense, shall comply with and cure
     Governmental Requirements relating to the public portions of the Building
     and

<PAGE>

     to the Demised Premises, provided that Tenant is not obligated to comply
     with them under the provisions of subdivision (a) of this Section.
     Landlord, at its expense, may contest the validity of any Governmental
     Requirements and postpone compliance therewith pending such contest.

               (d) Landlord represents that on the Commencement Date the Demised
     Premises will be free of Hazardous Materials and in compliance with
     applicable Governmental Requirements. Landlord, at its expense, agrees to
     remedy any condition arising out of a breach of the representations
     contained in this subdivision (d) and agrees to indemnify and hold Tenant
     harmless from and against any costs, expenses and damages arising out of a
     breach of such representations.

          Section 8.02.  If Tenant receives written notice of any violation of
any Governmental Requirements applicable to the Demised Premises, it shall give
prompt notice thereof to Landlord.

          Section 8.03.  Tenant will not clean, nor allow any window in the
Demised Premises to be cleaned, from the outside in violation of Section 202 of
the Labor Law or the rules of the Board of Standards and Appeals or of any other
board or body having or asserting jurisdiction.

                                   ARTICLE 9

                                   Insurance

          Section 9.01.  Provided Tenant has notice of the applicable
provisions, Tenant shall not do or permit to be done any act or thing in or upon
the Demised Premises which will invalidate or be in conflict with the
Certificate of Occupancy for the Building or the terms of the insurance policies
covering the Building and the property and equipment therein; and, subject to
Section 8.01, Tenant, at its expense, shall comply with all rules, orders,
regulations and requirements of the New York Board of Fire Underwriters or any
other similar body having jurisdiction, and of the insurance carriers, and shall
not knowingly do or permit anything to be done in or upon the Demised Premises
in a manner which increases the rate of insurance for the Building or any
property or equipment therein over the rate in effect on the Commencement Date,
provided further that nothing in this Section shall prohibit the uses permitted
under Section 4.01.

          Section 9.02.  If, by reason of Tenant's failure to comply with the
provisions of Section 9.01 or any of the other provisions of this Lease, the
rate of insurance for the Building or the property and equipment of Landlord
shall be higher than on the Commencement Date, Tenant shall pay to Landlord any
additional or increased insurance premiums to the extent resulting therefrom
thereafter paid by Landlord, and Tenant shall make such payment forthwith on
demand of Landlord.  In any action or proceeding wherein Landlord and Tenant

<PAGE>

are parties, a schedule or "make up" of any insurance rate for the Building or
Demised Premises issued by the New York Fire Insurance Exchange, or other body
establishing fire insurance rates for the Building, shall be conclusive evidence
of the facts therein stated and of the several items and charges in the
insurance rates then applicable to the Building or Demised Premises.

          Section 9.03.  (a)  Tenant covenants to provide on or before the
     Commencement Date and to keep in force during the term hereof, the
     following insurance coverage:

                   (i) For the benefit of Landlord, Tenant and any mortgagee, a
          commercial policy of liability insurance protecting and indemnifying
          Landlord, Tenant and any mortgagee against any and all claims for
          personal injury, death or property damage occurring upon, in or about
          the Demised Premises, and the public portions of the Building in
          connection with any act of Tenant, its employees, agents, contractors,
          customers, invitees and visitors including, without limitation,
          personal injury, death or property damage resulting from any work
          performed by or on behalf of Tenant, with coverage of not less than
          $5,000,000.00 combined single limit for personal injury, death and
          property damage arising out of one occurrence or accident.

                   (ii) Fire and extended coverage in an amount adequate to
          cover the cost of replacement of all personal property, fixtures,
          furnishings and equipment, including Tenant's work (as referred to in
          Section 5.01), located in the Demised Premises.

               (b) All such insurance shall (i) be effected under valid and
     enforceable policies, (ii) be issued by insurers of recognized
     responsibility authorized to do business in the State of New York, (iii)
     contain a provision whereby the insurer agrees not to cancel the insurance
     without thirty (30) days' prior written notice to Landlord, and (iv)
     contain a provision that no act or omission of Tenant shall result in
     forfeiture of the insurance as against Landlord.

          On or before the Commencement Date, Tenant shall deliver to Landlord
duplicate originals of the aforesaid policies or certificates evidencing the
aforesaid insurance coverage, and renewal policies or certificates shall be
delivered to Landlord at least thirty (30) days prior to the expiration date of
each policy with proof of payment of the premiums thereof.

          Section 9.04   Landlord shall maintain fire and extended coverage
insurance covering the Building in an amount required by the mortgagee, and
shall also

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maintain liability insurance.

          Section 9.05.  Landlord and Tenant shall each secure an appropriate
clause in, or an endorsement upon, each fire or extended coverage policy
obtained by it and covering the Building, the Demised Premises or the personal
property, fixtures and equipment located therein or thereon, pursuant to which
the respective insurance companies waive subrogation or permit the insured,
prior to any loss, to agree with a third party to waive any claim it might have
against said third party.  The waiver of subrogation or permission for waiver of
any claim herein before referred to shall extend to the agents of each party and
its employees and, in the case of Tenant, shall also extend to all other persons
and entities occupying or using the Demised Premises in accordance with the
terms of this lease.  If and to the extent that such waiver or permission can be
obtained only upon payment of an additional charge, then, the party benefitting
from the waiver or permission shall pay such charge upon demand, or shall be
deemed to have agreed that the party obtaining the insurance coverage in
question shall be free of any further obligations under the provisions hereof
relating to such waiver or permission.

          Subject to the foregoing provisions of this Section 9.05, and insofar
as may be permitted by the terms of the insurance policies carried by it, (i)
each party hereby releases the other with respect to any claim (including a
claim for negligence) which it might otherwise have against the other party for
loss, damages or destruction with respect to its property by fire or other
casualty (including rental value or business interruption, as the case may be)
occurring during the term of this Lease covered by insurance and (ii) Tenant
releases other tenants but only to the extent that the policies of such other
tenants permit a similar waiver for the benefit of Tenant and such other tenant
gives such a waiver.

                                  ARTICLE 10

                         Damage by Fire or Other Cause

          Section 10.01.  If the Demised Premises shall be damaged by fire or
other casualty, the damage shall be repaired by and at the expense of Landlord
and the minimum rent and additional rent pursuant to the provisions of Article
22 until such repairs shall be made, shall be apportioned according to the part
of the Demised Premises which is usable and accessable by Tenant.  Landlord
shall have no responsibility to repair any damage to Tenant's work (as referred
to in Section 5.01), the same being the responsibility of Tenant.  No penalty
shall accrue for delays which may arise by reason of adjustment of insurance by
Landlord, unavoidable delays (as hereinafter defined), or any other cause beyond
Landlord's reasonable control.  Tenant shall give notice to Landlord promptly
upon learning thereof in case of fire or other damage to the Demised Premises.
If the Demised Premises are totally or substantially damaged or are rendered
wholly or substantially unusable by fire or any such other casualty, or if the
Building shall be so damaged that Landlord shall decide to demolish it or to
rebuild it (whether or not the Demised Premises shall have been damaged),
Landlord at its election may terminate this Lease by written notice to Tenant,
within ninety (90) days after such fire or

<PAGE>

other casualty, and thereupon the term of this Lease shall expire by lapse of
time upon the third (3rd) day after such notice is given, and Tenant shall
vacate and surrender the Demised Premises to Landlord. However, if more than
twenty-five (25%) percent of the rentable square feet of the Demised Premises
shall be damaged during the last year of the term hereof, either Landlord or
Tenant, at its election, may terminate this Lease by written notice to the other
within sixty (60) days after such fire or other casualty, and thereupon the term
of this Lease shall expire upon the third (3/rd/) day after such notice is given
and Tenant shall vacate and surrender the Demised Premises to Landlord. Tenant
shall not be liable under this Lease for anything accruing after the date of
such expiration. Notwithstanding the foregoing, if Landlord does not
substantially complete such repairs within six (6) months from the date of such
casualty (as such period may be extended pursuant to Article 34), then Tenant
may elect to terminate this Lease by notice to Landlord within ten (10) days
following the expiration of such time period, and thereupon the term of this
Lease shall expire on the thirtieth (30/th/) day after such notice is given and
Tenant shall vacate and surrender the Demised Premises to Landlord, unless
within such thirty (30) day period, Landlord substantially completes such
repairs, in which event this Lease shall remain in full force and effect. Tenant
hereby waives the provisions of Section 227 of the Real Property Law, and the
provisions of this Article shall govern and control in lieu thereof.

          Section 10.02.  No damages of compensation shall be payable by
Landlord nor shall Tenant make any claim for inconvenience, loss of business or
annoyance arising from any repair or restoration of any portion of the Demised
Premises or of the Building.  Landlord shall use its best efforts to commence
and effect such repairs promptly and in such manner as not to unreasonably
interfere with Tenant's occupancy.

                                  ARTICLE 11

                      Assignment, Subletting, Mortgaging

          Section 11.01.  Tenant will not, by operation of law or otherwise,
assign, mortgage or encumber this Lease, or sublet or permit the Demised
Premises or any part thereof to be occupied or used by others for desk space,
mailing privileges or otherwise, without Landlord's prior written consent in
each instance, which consent shall not be unreasonably withheld or delayed
subject to the provisions of Section 11.07.  If this Lease be assigned, or if
the Demised Premises or any part thereof be underlet or occupied by anybody
other than Tenant, Landlord, may, after default by Tenant, collect rent from the
assignee, undertenant or occupant, and apply the net amount collected to the
rent herein reserved, but no assignment, underletting, occupancy or collection
shall be deemed a waiver of the provisions hereof, the acceptance of the
assignee, undertenant or occupant as tenant, or a release of Tenant from the
further performance by Tenant of covenants on the part of Tenant herein
contained.  The consent by Landlord to any assignment, subletting, mortgage or
encumbrance shall not in any manner be construed to relieve Tenant from
obtaining Landlord's express consent to any other or further assignment,
subletting, mortgage or encumbrance.  In no event shall any permitted sublessee
assign or encumber its sublease or further sublet all or any portion of its
sublet space,

<PAGE>

or otherwise suffer or permit the sublet space or any part thereof to be used or
occupied by others, without Landlord's prior written consent in each instance,
which consent shall not be unreasonably withheld or delayed subject to the
provisions of Section 11.07.

          Section 11.02.  If Tenant shall at any time or times during the term
of this Lease desire to assign this Lease or sublet all or part of the Demised
Premises, Tenant shall give notice thereof to Landlord, which notice shall be
accompanied by (a) a conformed or photostatic copy of the proposed assignment or
sublease, the effective or commencement date of which shall be not less than
thirty (30) nor more than 180 days after the giving of such notice, (b) 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
Demised Premises, and (c) current financial information with respect to the
proposed assignee or subtenant, including, without limitation, its most recent
financial report.  Such notice shall be deemed an offer from Tenant to Landlord
whereby Landlord (or Landlord's designee) may, at its option, (i) sublease such
space (hereinafter called the "Leaseback Space") from Tenant upon the terms and
conditions hereinafter set forth (if the proposed transaction is a sublease of
all or part of the Demised Premises), (ii) terminate this Lease (if the proposed
transaction is an assignment or a sublease (whether by one sublease or a series
of related or unrelated subleases) of all or substantially all of the Demised
Premises, or (iii) terminate this Lease with respect to the Leaseback Space (if
the proposed transaction is a sublease of part of the Demised Premises).  Said
options may be exercised by Landlord by notice to Tenant at any time within
twenty (20) days after such notice has been given by Tenant to Landlord; and
during such twenty (20) day period Tenant shall not assign this Lease nor
sublet such space to any person.

          Section 11.03.  If Landlord exercises its option to terminate this
Lease in the case where Tenant desires either to assign this Lease or sublet
(whether by one sublease or a series of related or unrelated subleases) all or
substantially all of the Demised Premises, then this Lease shall end and expire
on the date that such assignment or sublet was to be effective or commence, as
the case may be, and the minimum rent and additional rent shall be paid and
apportioned to such date.

          Section 11.04.  If Landlord exercises its option to terminate this
Lease in part in any case there Tenant desires to sublet part of the Demised
Premises, then (a) this Lease shall end and expire with respect to such part of
the Demised Premises on the date that the proposed sublease was to commence; and
(b) from and after such date the minimum rent and additional rent shall be
adjusted, based upon the proportion that the rentable area of the Demised
Premises remaining bears to the total rentable area of the Demised Premises; and
(c) Landlord shall pay the costs incurred by Landlord in physically separating
such part of the Demised Premises from the balance of the Demised Premises and
in complying with any laws and requirements of any public authorities relating
to such separation.

          Section 11.05.  If Landlord exercises its option to sublet the
Leaseback Space, such sublease to Landlord or its designee (as subtenant) shall
be at the lower of (i) the rental rate per rentable square foot of minimum rent
and additional rent then payable pursuant

<PAGE>

to this Lease or (iii) the rentals set forth in the proposed sublease, and shall
be for the same term as that of the proposed subletting, and such sublease:

               (a) shall be expressly subject to all of the covenants,
     agreements, terms, provisions and conditions of this Lease except such as
     are irrelevant or inapplicable, and except as otherwise expressly set forth
     to the contrary in this Section;

               (b) Such sublease shall be upon the same terms and conditions as
     those contained in the proposed sublease, except such as are irrelevant or
     inapplicable and except as otherwise expressly set forth to the contrary in
     this Section;

               (c) Such sublease shall give the sublesee the unqualified and
     unrestricted right, without Tenant's permission, to assign such sublease or
     any interest therein and/or to sublet the Leaseback Space and to make any
     and all changes, alterations, and improvements in the space covered by such
     sublease at no cost or liability to Tenant and if the proposed sublease
     will result in all or substantially all of the Demised Premises being
     sublet, grant Landlord or its designee the option to extend the term of
     such sublease for the balance of the term of this Lease less one (1) day;

               (d) Such sublease shall provide that any assignee or further
     subtenant, of Landlord or its designee, may, at the election of Landlord,
     be permitted to make alterations, decorations and installations in the
     Leaseback Space or any part thereof and shall also provide in substance
     that any such alterations, decorations and installations in the Leaseback
     Space therein made by any assignee or subtenant of Landlord or its designee
     may be removed, in whole or in part, by such assignee or subtenant, at its
     option, prior to or upon the expiration or other termination of such
     sublease provided that such assignee or subtenant, at its expense, shall
     repair any damage and injury to that portion of the Leaseback Space so
     sublet caused by such removal and restore to the condition such space was
     in at the beginning of the sublease term for other than customary office
     installations; and

               (e) Such sublease shall also provide that (i) the parties to such
     sublease expressly negate any intention that any estate created under such
     sublease be merged with any other estate held by either of said parties,
     (ii) any assignment or subletting by Landlord or its designee (as the
     subtenant) may be for any purpose or purposes that Landlord, in Landlord's
     reasonable discretion, shall deem suitable or appropriate, (iii) Landlord,
     at Tenant's expense, may make such alterations as may be required or deemed
     necessary by Landlord to physically separate the Leaseback Space from the
     balance of the Demised Premises and to comply with any laws and
     requirements of public authorities

<PAGE>

     relating to such separation, and (iv) that at the expiration of the term of
     such sublease, Tenant will accept the space covered by such sublease in its
     then existing condition, subject to the obligations of the sublessee to
     make such repairs thereto as may be necessary to restore the premises
     demised by such sublease to a comparable condition as such space was in at
     the beginning of the sublease term.

          Section 11.06. (a)  If Landlord exercises its option to sublet the
     Leaseback Space, Landlord shall indemnify and save Tenant harmless from all
     obligations under this Lease as to the Leaseback Space during the period of
     time it is so sublet to Landlord.

               (b) Performance by Landlord, or its designee, under a sublease of
     the Leaseback Space shall be deemed performance by Tenant of any similar
     obligation under this Lease and any default under any such sublease shall
     not give rise to a default under a similar obligation contained in this
     Lease, nor shall Tenant be liable for any default under this Lease or
     deemed to be in default hereunder if such default is occasioned by or
     arises from any act or omission of any occupant holding under or pursuant
     to any such sublease.

               (c) Tenant shall have no obligation, at the expiration or earlier
     termination of the term of this Lease, to remove any alteration,
     installation or improvement made in the Leaseback Space by Landlord or by
     any occupant thereof.

          Section 11.07.  In the event Landlord does not exercise an option
provided to it pursuant to Section 11.02 and provided that Tenant is not in
default in any of Tenant's obligations under this Lease, Landlord's consent
(which must be in writing and in form reasonably satisfactory to Landlord) to
the proposed assignment or sublease shall not be unreasonably withheld or
delayed, provided and upon condition that:

               (a) Tenant shall have complied with the provisions of Section
     11.02 and Landlord shall not have exercised any of its options under said
     Section 11.02 within the time permitted therefor;

               (b) In Landlord's judgment, the proposed assignee or subtenant is
     engaged in a business and the Demised Premises, or the relevant part
     thereof, will be used in a manner which (i) is limited to the use expressly
     permitted under Sections 4.01 and 4.02 of this Lease, and (ii) is in
     keeping with the then standards of the Building;

               (c) The proposed assignee or subtenant is a reputable person of
     good character and with sufficient financial worth considering the
     responsibility involved, and Landlord has been furnished with reasonable
     proof

<PAGE>

     thereof;

               (d) Neither (i) the proposed assignee or sublessee nor (ii) any
     person which, directly or indirectly, controls, is controlled by or is
     under common control with, the proposed assignee or sublessee, is then an
     occupant of any part of the Building other than the Demised Premises;

               (e) The proposed assignee or sublessee is not a person with whom
     Landlord is currently negotiating to lease space in the Building;

               (f) The proposed sublease shall be in form reasonably
     satisfactory to Landlord and shall comply with the provisions of this
     Article;

               (g) At any one time there shall not be more than four (4)
     unrelated subtenants on any full floor and not more than two (2) unrelated
     subtenants on any partial floor (including Landlord or its designee) in the
     Demised Premises;

               (h) Tenant shall reimburse Landlord on demand for any reasonable
     costs that may be incurred by Landlord in connection with said assignment
     or sublease, including, without limitation, the reasonable costs incurred
     in making investigations as to the acceptability of the proposed assignee
     or subtenant, and reasonable legal costs incurred in connection with the
     granting of any requested consent;

               (i) Tenant shall not have (i) advertised in any way the
     availability of the Demised Premises without prior notice to Landlord, or
     (ii)  listed the Demised Premises at a rental rate less than the minimum
     rent or additional rent at which Landlord is then offering to lease other
     space in the Building; and

               (j) 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
     New York State.

          Except for any subletting by Tenant to Landlord or its designee
pursuant to the provisions of this Article, each subletting pursuant to this
Article shall be subject to all of the covenants, agreements, terms, provisions
and conditions contained in this Lease.  Notwithstanding any such subletting to
Landlord or any such subletting to any other subtenant and/or acceptance of rent
or additional rent by Landlord from any subtenant, Tenant shall and will remain
fully liable for the payment for the minimum rent and additional rent due and to
become due hereunder and for the performance of all the covenants, agreements,
terms, provisions and conditions contained in this Lease on the part of Tenant
to be performed and

<PAGE>

all acts and omissions of any licensee or subtenant or anyone claiming under or
through any subtenant which shall be in violation of any of the obligations of
this Lease, and any such violation shall be deemed to be a violation by Tenant.
Tenant further agrees that notwithstanding any such subletting, no other person
claiming through or under Tenant (except as provided in Section 11.05) shall or
will be made except upon compliance with and subject to the provisions of this
Article. If Landlord shall decline to give its consent to any proposed
assignment or sublease (provided landlord has not unreasonably withheld or
delayed its consent), or if Landlord shall exercise its option under Section
11.02, Tenant shall indemnify, defend and hold harmless Landlord against and
from any and all loss, liability, damages, costs and expenses (including
reasonable counsel fees) resulting from any claims that may be made against
Landlord by the proposed assignee or sublessee or by any brokers or other
persons claiming a commission or similar compensation in connection with the
proposed assignment or sublease. Notwithstanding the foregoing, Tenant, without
Landlord's consent, may allow a portion of the Demised Premises to be occupied
by a majority owned subsidiary or an affiliate or related entity controlling,
controlled by or under common control with Tenant, provided such occupancy shall
not create any landlord and tenant relationship or privity as between Landlord
and any such occupant and Tenant shall give Landlord prior reasonable notice of
such proposed occupancy. Such occupancies shall not be counted towards the total
allowed under Section 11.07(g), and Landlord has no rights of termination or
recapture with respect to such occupancies.

          Section 11.08.  In the event that (a) Landlord fails to exercise its
options under Section 11.02 and consents to a proposed assignment or sublease,
and (b) Tenant fails to execute and deliver the assignment or sublease to which
Landlord consented within ninety (90) days after the giving of such consent,
then, Tenant shall again comply with all of the provisions and conditions of
Section 11.02 before assigning this Lease or subletting all or part of the
Demised Premises.

          Section 11.09.  With respect to each and every sublease or subletting
authorized by Landlord under the provisions of this Lease, it is further agreed:

               (a) No subletting shall be for a term ending later than one day
     prior to the expiration date of this Lease;

               (b) No sublease shall be valid, 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;

               (c) Each sublease shall provide that it is subject and
     subordinate to this Lease and to the matters to which this Lease is or
     shall be subordinate, and that in the event of termination, re-entry or
     dispossess by Landlord under this Lease Landlord may, at its option, take
     over all of the right, title and interest of Tenant, as sublessor, under
     such sublease, and such subtenant shall, at Landlord's option, attorn to
     Landlord pursuant to the then

<PAGE>

     executory provisions of such sublease, except that Landlord shall not (i)
     be liable for any previous act or omission of Tenant under such sublease,
     (ii) be subject to any offset, not expressly provided in such sublease,
     which thereto accrued to such subtenant against Tenant, or (iii) be bound
     by any previous modification of such sublease or by any previous prepayment
     of more than one month's rent.

          Section 11.10.  If Landlord gives its consent to any assignment of
this Lease or to any sublease, Tenant shall, in consideration therefor, pay to
Landlord, as additional rent:

               (a) in the case of an assignment of this Lease or an assignment
     by any sublease, an amount equal to one-half of all sums and other
     considerations paid to Tenant from the assignee for such assignment or paid
     to Tenant by any sublessee or other person claiming through or under Tenant
     for such assignment (including, but not limited to sums paid for the sale
     of Tenant's or sublessee's fixtures, leasehold improvements, less, in case
     of a sale thereof, the then net unamortized or undepreciated cost thereof
     determined on the basis of Tenant's or sublessee's federal income tax
     returns).  The sums payable to Landlord under this Section 11.10(a) shall
     be paid to Landlord as and when paid by such assignee to Tenant; and

               (b) in the case of a sublease, an amount equal to one-half of the
     rents and charges and other consideration payable under the sublease to
     Tenant by the subtenant or paid to Tenant by any such sublessee or other
     person claiming through or under Tenant in connection with such subletting
     which is in excess of all  rent accruing during the term of the sublease in
     respect of the subleased space (at the rate per square foot payable by
     Tenant hereunder or such sublessee) pursuant to the terms of this Lease
     (including, but not limited to, sums paid for the sale or rental of
     Tenant's fixtures, leasehold improvements, less, in the case of the sale
     thereof, the then net unamortized or undepreciated cost thereof determined
     on the basis of Tenant's or sublessee's federal income tax returns).  The
     sums payable to Landlord under this Section 11.10(b) shall be paid to
     Landlord as and when paid by such subtenant to Tenant.

               (c) For the purposes of computing the sums payable by Tenant to
     Landlord under subparagraphs (a) and (b) hereof, there shall be first
     excluded from the consideration payable to Tenant by any assignee or
     sublessee any transfer taxes, rent concession, reasonable attorneys' fees,
     reasonable brokerage commissions, advertising costs and fix-up costs paid
     by Tenant with respect to such assignment or subletting, but only to the
     extent any such sums are allocable to the period of this Lease (in the case
     of any assignment), or the term of any sublease.

          Section 11.11.  If Tenant or any subtenant is a corporation,
partnership, limited

<PAGE>

liability company or other entity, the provisions of Section 11.01 shall apply
to a transfer (by one or more transfers) of a majority of the stock,
partnership, membership or other ownership interests or transfer of all or
substantially all of the assets of Tenant or such subtenant, as the case may be,
as if such transfer of a majority of the stock, partnership, membership or other
ownership interests or all or substantially all of the assets of Tenant or such
subtenant were an assignment of this Lease; but said provisions and the
provisions of Sections 11.02 and 11.10 shall not apply to transactions with a
corporation, partnership, limited liability company or other entity into or with
which Tenant or such subtenant is merged or consolidated, or to which all or
substantially all of the assets of Tenant are transferred, or to any
corporation, partnership, limited liability company or other entity which
controls or is controlled by Tenant or such subtenant or is under common control
with Tenant or such subtenant, provided that in any of such events (i) the
successor to Tenant or such subtenant has a net worth computed in accordance
with generally accepted accounting principles at least equal to the greater of
(1) the net worth of Tenant or such subtenant immediately prior to such merger,
consolidation or transfer, or (2) the net worth of Tenant herein named on the
date of this Lease or the net worth of such subtenant on the date of such
sublease, and (ii) proof satisfactory to Landlord of such net worth shall have
been delivered to Landlord at least ten (10) days prior to the effective date of
any such transaction. Notwithstanding the foregoing, without Landlord's consent,
subject to the provisions of Section 11.11 Tenant may assign this Lease, or
subject to the provision of the last paragraph of Section 11.07 and Section
11.09 Tenant may sublet a part of the Demised Premises, to a controlled
subsidiary or controlled affiliate of Tenant, provided a duly executed
counterpart of such assignment together with the assumption by the assignee or
duly executed counterpart of such sublease, as the case may be, is delivered to
Landlord upon the earlier of (a) at least ten (10) days prior to its effective
date or (b) within three (3) business days of the transaction to which such
asisgnment or sublease is not subject to confidentiality requirements but in no
event more than ten (10) days after the effective date. Such subleases shall not
be counted towards the total allowed under Section 11.07(g) and Landlord has no
rights of termination or recapture with respect to the subleases or assignments
permitted in this Section 11.11.

          Section 11.12.  Any assignment or transfer, whether made with
Landlord's consent pursuant to Section 11.06 or without Landlord's consent
pursuant to Section 11.10, 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 and whereby the assignee shall agree that the provisions
in this Article 11 shall, notwithstanding such assignment or transfer, continue
to be binding upon it in respect of all future assignments and transfers.  The
original named Tenant covenants that, notwithstanding any assignment or
transfer, whether or not in violation of the provisions of this Lease, and
notwithstanding the acceptance of minimum rent and/or additional rent by
Landlord from an assignee, transferee, or any other party, the original named
Tenant shall remain fully liable for the payment of the minimum rent and
additional rent and for the other obligations of this Lease on the part of
Tenant to be performed or observed.

<PAGE>

          Section 11.13.  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 extending the time of, or modifying any of the
obligations of, this Lease, or by any waiver or failure of Landlord to enforce
any of the obligations of this Lease.

          Section 11.14.  The listing of any name ot her than that of Tenant,
whether on the doors of the Demised Premises, or the Building directory, if any,
or otherwise, shall not operate to vest any right or interest in this Lease or
in the Demised Premises, nor shall it be deemed to be the consent of Landlord to
any assignment or transfer of this Lease, to any sublease of the Demised
Premises, or to the use or occupancy thereof by others.  Landlord at its cost,
shall provide Tenant up to thirty (30) listings in the main lobby for Tenant and
permitted occupants and subtenants.

                                  ARTICLE 12

                Liability  and Indemnity by Landlord and Tenant

          Section 12.01.  Each party shall indemnify the other against and save
the other harmless from any liability to and claim by or on behalf of any
person, firm, governmental authority, corporation or entity for personal injury,
death or property damage, arising:

               (a) (i) with respect to Tenant, from its use of the Demised
     Premises, or from any work whatsoever done or omitted to be done by Tenant,
     its employees, agents, contractors, customers, invitees or visitors, or
     from any accident thereat, and (ii) with respect to Landlord, from any work
     whatsoever done or omitted to be done in the Building by Landlord, its
     agents, contractors or employees; and

               (b) from any breach or default by either party of and under any
     of the terms, covenants and conditions of this Lease on such party's part
     to be performed.

          Each party also shall indemnify the other against and save the other
harmless from all costs, reasonable counsel fees, expenses and penalties
incurred by the other in connection with any such liability or claim other than
such liability or claim incurred as a result of such party's negligence or
willful misconduct.

          If any action or proceeding shall be brought against either party in
connection with any such liability or claim, the other party (the "Indemnitor")
, on notice from the party against whom such action or proceeding was commenced
(the "Indemitee") , shall defend such action or proceeding, at the Indemnitor's
expense, by counsel reasonably satisfactory to the Indemnitee , or by the
attorney for the Indemnitor's insurance carrier whose insurance policy

<PAGE>

covers the liability or claim.

          Section 12.02.  Landlord shall not be liable for any damage to
property of Tenant or of others entrusted to employees of the Building, nor for
the loss of or damage to any property of Tenant by theft or otherwise, except if
due to the negligence or willful act of Landlord, its agents, contractors or
employees. Landlord and its agents shall not be liable for any injury or damage
to persons or property 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 sub-
surface or from any other place or by dampness or by any other cause of
whatsoever nature, except if due to the negligence or willful act of Landlord,
its agents, contractors or employees; nor shall Landlord be liable for any such
damage caused by other tenants or persons in the Building or caused by
operations in construction of any public or quasi-public work. If, at any time
any windows of the Demised Premises are permanently closed, darkened or bricked
up by reason of the requirements of law or temporarily closed or darkened by
reason of repairs, alterations or maintenance by Landlord, Landlord shall not be
liable for any damage Tenant may sustain thereby and Tenant shall not be
entitled to any compensation therefor nor abatement of rent nor shall the same
release Tenant from its obligations hereunder nor constitute an eviction.

          Tenant shall give immediate notice to Landlord upon its discovery of
accidents in the Demised Premises.

          Section 12.03. (a)  If in this Lease it is provided that Landlord's
     consent or approval as to any matter will not be unreasonably withheld, and
     it is established by a court or body having final jurisdiction thereover
     that Landlord has been unreasonable, the only effect of such finding shall
     be that Landlord shall be deemed to have given its consent or approval; but
     Landlord shall not be liable to Tenant in any respect for money damages by
     reason of withholding its consent.

          (b)  If there is a dispute between Landlord and Tenant under Section
     11.07 relating to the reasonableness of the withholding of a consent or
     approval by Landlord, Tenant may, at its option, as its sole and exclusive
     remedy, submit such dispute to arbitration in the City of New York under
     the Expedited Procedures provisions of the Commercial Arbitration Rules of
     the American Arbitration Association or any successor (the "AAA")
     (presently Rules E-1 through E-10 and, to the extent applicable, Section R-
     19); provided, however, that with respect to any such arbitration, (i) the
     list of arbitrators referred to in Rule E-5 shall be returned within five
     (5) days from the date of mailing; (ii) the parties shall notify the AAA by
     telephone, within four (4) days of any objections to the arbitrator
     appointed and will have no right to object if the arbitrator so appointed
     was on the list submitted by the AAA and was not objected to in accordance
     with Rule E-5; (iii) the Notice of hearing referred to in Rule E-8 shall be
     four (4) days in advance of the hearing; (iv) the hearing shall be held
<PAGE>

     within seven (7) days after the appointment of the arbitrator; (v) the
     arbitrator shall have no right to award damages; and (vi) the decision and
     award of the arbitrator shall be final and conclusive on the parties. The
     sole issue to be submitted to the arbitrator, which shall be included as
     part of his oath, shall be the reasonableness of Landlord's determination
     to withhold consent or approval under the provisions of this Lease. The
     arbitrators conducting any arbitration shall be bound by the provisions of
     this Lease and shall not have the right or power to consider, determine or
     resolve any other issue or dispute between the parties, or to add to,
     subtract from, or otherwise modify such provisions. Landlord and Tenant
     agree to sign all documents and to do all other things necessary to submit
     any such matter to arbitration upon request of the other and further agree
     to, and hereby do, waive any and all rights they or either of them may at
     any time have to revoke their agreement hereunder to submit to arbitration
     and to abide by the decision rendered thereunder. Each of the arbitrators
     shall have at least ten (10) years' experience in the business of managing
     real estate or acting as a real estate broker with first-class office
     buildings located in Manhattan. Each party hereunder initially shall pay
     its own costs, fees and expenses in connection with any arbitration or
     other action or proceeding brought under this Article 12, and the expenses
     and fees of the arbitrators selected initially shall be shared equally by
     Landlord and tenant, provided, however, that the losing party shall
     reimburse the prevailing party for its reasonable expenses paid to
     unrelated third parties in connection with the foregoing. Notwithstanding
     any contrary provisions hereof, if Tenant shall submit such dispute to
     arbitration, then Landlord and Tenant agree that (i) the arbitrators may
     not award or recommend any damages to be paid by either party, and (ii) in
     no event shall either party be liable for, nor be entitled to recover, any
     damages.

                                  ARTICLE 13

                           Moving of Heavy Equipment

          Tenant shall not move any safe, heavy equipment or bulky matter in or
out of the Building without Landlord's written consent, which shall not be
unreasonably withheld.  If the movement of such items requires special handling,
Tenant agrees to employ only persons holding a Master Rigger's License to do
said work and all such work shall be done in full compliance with the
Administrative Code of the City of New York and other municipal requirements.
All such movements shall be made during hours which will least interfere with
the normal operations of the Building, and all damage caused by such movement
shall be promptly repaired by Tenant at Tenant's expense.

                                  ARTICLE 14

                                 Condemnation
<PAGE>

          Section 14.01.  In the event that the whole or more than ten (10%)
percent of the Demised Premises shall be condemned or taken in any manner for
any public or quasi-public use, this Lease and the term and estate hereby
granted shall forthwith cease and terminate as of the date of vesting of title.
In the event that ten (10%) percent or less  of the Demised Premises shall be so
condemned or taken, then, effective as of the date of vesting of title, the
minimum rent and additional rent hereunder for such part shall be equitably
abated and this Lease shall continue as to such part not so taken.  In the event
that only a part of the Building shall be so condemned or taken, then (a) if
substantial structural alteration or reconstruction of the Building shall, in
the opinion of Landlord, be necessary or appropriate as a result of such
condemnation or taking (whether or not the Demised Premises be affected),
Landlord may, at its option, terminate this Lease and the term and estate hereby
granted as of the date of such vesting of title by notifying Tenant in writing
of such termination within sixty (60) days following the date on which Landlord
shall have received notice of the vesting of title, or (b) if Landlord does not
elect to terminate this Lease, as aforesaid, this Lease shall be and remain
unaffected by such condemnation or taking, except that the minimum rent and
additional rent shall be abated to the extent, if any, hereinbefore provided.
In the event that only a part of the Demised Premises shall be so condemned or
taken and this Lease and the term and estate hereby granted are not terminated
as hereinbefore provided, Landlord, out of the portion of the award allocated
for such purpose , will restore with reasonable diligence the remaining
structural portions of the Demised Premises as nearly as practicable to the same
condition as it was in prior to such condemnation or taking.

          Section 14.02.  In the event of termination in any of the cases
hereinabove provided, this Lease and the term and estate hereby granted shall
expire as of the date of such termination with the same effect as if that were
the Expiration Date and the rent hereunder shall be apportioned as of such date.

          Section 14.03.  In the event of any condemnation or taking hereinabove
mentioned of all or a part of the Building, Landlord shall be entitled to
receive the entire award in the condemnation proceeding, including any award
made for the value of the estate vested by this Lease in Tenant, and Tenant
hereby expressly assigns to Landlord any and all right, title and interest of
Tenant now or hereafter arising in or to any such award or any part thereof, and
Tenant shall be entitled to receive no part of such award.  Notwithstanding the
foregoing, Tenant may make a separate claim for Tenant's moveable trade fixtures
and moving expenses, provided the same shall not affect or reduce Landlord's
award.

                                  ARTICLE 15

            Entry, Right to Change Public Portions of the Building

          Section 15.01.  Tenant shall permit Landlord to erect, use and
maintain pipes and conduits in and through the walls, within the ceiling or
below the floors of the Demised Premises.  Landlord, or its agents or designee
shall have the right, on prior written notice
<PAGE>

(except no notice in an emergency), to enter the Demised Premises for the
purpose of making such repairs or alterations as Landlord shall desire, shall be
required or shall have the right to make under the provisions of this Lease; and
shall also have the right to enter the Demised Premises for the purpose of
inspecting them or exhibiting them to prospective purchasers or lessees of the
entire Building or to prospective mortgagees or to prospective assignees of any
such mortgagees. Landlord shall, during the progress of any work in the Demised
Premises, be allowed to take all material into and upon the Demised Premises
that may be required for the repairs or alterations above mentioned without the
same constituting an eviction of Tenant in whole or in part and the rent
reserved shall in no wise abate, except as otherwise provided in this Lease,
while said repairs or alterations are being made. However, Landlord shall use
reasonable efforts to make such repairs or alterations in a manner to minimize
its interference with the normal conduct of Tenant's business, provided Landlord
shall not be required to employ overtime or premium labor.

          Section 15.02.  During the twelve (12) months prior to the expiration
of the term of this Lease, Landlord may exhibit the Demised Premises to
prospective tenants.

          Section 15.03.  Landlord shall have the right at any time without
thereby creating an actual or constructive eviction or incurring any liability
to Tenant therefor, to change the arrangement or location of such of the
following as are not contained within the Demised Premises: entrances,
passageways, doors and doorways, corridors, elevators, stairs, toilets, and
other like public service portions of the Building; and to put so-called "solar
film" or other energy-saving installations on the inside and outside of the
windows. All parts (except surfaces facing the interior of the Demised Premises)
of all walls, windows and doors bounding the Demised Premises (including
exterior Building walls, exterior core corridor walls, exterior doors and
entrances), all space in or adjacent to the Demised 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 Demised Premises and Landlord shall have
the use thereof, as well as access thereto through the Demised Premises for the
purposes of operation, maintenance, alteration and repair. However, Landlord
shall use reasonable efforts to make such repairs or alterations in a manner to
minimize its interference with the normal conduct of Tenant's business, provided
Landlord shall not be required to employ overtime or premium labor.

          Section 15.04.  Landlord shall have the right at any time to name the
Building as it desires and to change any and all such names at any time
thereafter.

                                  ARTICLE 16

                         Conditional Limitations, Etc.

          Section 16.01.  If at any time during the term of this Lease:

               (a)  Tenant or any guarantor of this Lease shall file a petition
<PAGE>

     in bankruptcy or insolvency or for reorganization or arrangement or for the
     appointment of a receiver of all or a portion of Tenant's or such
     guarantor's property, or

               (b)  Any petition of the kind referred to in subdivision (a) of
     this Section shall be filed against Tenant or such guarantor and such
     petition shall not be vacated, discharged or withdrawn within ninety (90)
     days, or

               (c)  Tenant or such guarantor shall be adjudicated a bankrupt by
     any court, or

               (d)  Tenant or such guarantor shall make an assignment for the
     benefit of creditors, or

               (e)  a permanent receiver shall be appointed for the property of
     Tenant or such guarantor by order of a court of competent jurisdiction by
     reason of the insolvency of Tenant or such guarantor (except where such
     receiver shall be appointed in an involuntary proceeding, if he shall not
     be withdrawn within ninety (90) days after the date of his appointment),

then Landlord, at Landlord's option, may terminate this Lease on five (5) days'
notice to Tenant, and upon such termination, Tenant shall quit and surrender the
Demised Premises to Landlord.

          Section 16.02  (a)  If Tenant assumes this Lease and proposes to
     assign the same pursuant to the provisions of the Bankruptcy Code, 11
     U.S.C. (S) 101 et seq. (the "Bankruptcy Code") to any person or entity who
     shall have made a bona fide offer to accept an assignment of this Lease on
     terms acceptable to Tenant, then notice of such proposed assignment,
     setting forth (i) the name and address of such person, (ii) all of the
     terms and conditions of such offer, and (iii) the adequate assurance to be
     provided Landlord to assure such person's future performance under the
     Lease, including, without limitation, the assurance referred to in section
     365(b)(1) of the Bankruptcy Code, shall be given to Landlord by Tenant not
     later than twenty (20) days after receipt by Tenant but in no event later
     than ten (10) days prior to the date that Tenant shall make application to
     a court of competent jurisdiction for authority and approval to enter into
     such assignment and assumption, and Landlord shall thereupon have the prior
     right and option, to be exercised by notice to Tenant given at any time
     prior to the effective date of such proposed assignment, to accept an
     assignment of this Lease upon the same terms and conditions and for the
     same consideration, if any, as the bona fide offer made by such person,
     less any brokerage commissions which may be payable out of the
     consideration to be paid by such person for the assignment of this Lease.
<PAGE>

               (b)  If this Lease is assigned to any person or entity pursuant
     to the provisions of the Bankruptcy Code, any and all monies or other
     considerations payable or otherwise delivered in connection with such
     assignment shall be paid or delivered to Landlord, shall be and remain the
     exclusive property of Landlord and shall not constitute property of Tenant
     or of the estate of Tenant within the meaning of the Bankruptcy Code.  Any
     and all monies or other considerations constituting Landlord's Property
     under the preceding sentence not paid or delivered to Landlord shall be
     held in trust for the benefit of Landlord and shall be promptly paid to
     Landlord.

               (c)  Any person or entity to which this Lease is assigned
     pursuant to the provisions of the Bankruptcy Code, shall be deemed without
     further act or deed to have assumed all of the obligations arising under
     this Lease on and after the date of such assignment. Any such assignee
     shall upon demand execute and deliver to Landlord an instrument confirming
     such assumption.

               (d)  Nothing contained in this Section shall, in any way,
     constitute a waiver of the provisions of this Lease relating to assignment.
     Tenant shall not, by virtue of this Section, have any further rights
     relating to assignment other than those granted in the Bankruptcy Code.

               (e)  Notwithstanding anything in this Lease to the contrary, all
     amounts payable by Tenant to or on behalf of Landlord under this Lease,
     whether or not expressly denominated as rent, shall constitute rent for the
     purposes of Section 502(b)(6) of the Bankruptcy Code.

               (f)  The term "Tenant" as used in this Section includes any
     trustee, debtor in possession, receiver, custodian or other similar
     officer.

          Section 16.03.  If this Lease shall terminate pursuant to the
provisions of Section 16.01:

               (a)  Landlord shall be entitled to recover from Tenant arrears in
     minimum rent and additional rent and, in addition thereto as liquidated
     damages, an amount equal to the difference between the minimum rent and
     additional rent for the unexpired portion of the term of this Lease which
     had been in force immediately prior to the termination effected under
     Section 16.01 of this Article and the fair and the reasonable rental value
     of the Demised Premises, on the date of termination, for the same period,
     both discounted at the rate of eight (8%) percent per annum to the date of
     termination; or

               (b)  Landlord shall be entitled to recover from Tenant arrears in
     minimum rent and additional rent and, in addition thereto as liquidated
<PAGE>

     damages, an amount equal to the maximum allowed by statute or rule of law
     in effect at the time when and governing the proceedings in which such
     damages are to be proved, whether or not such amount be greater or less
     than the amount referred to in subdivision (a) of this Section.

          Section 16.04.  (a)  If Tenant shall fail to make any payment of any
     minimum rent or additional rent when the same becomes due and payable, or
     if the Demised Premises become  deserted, or if Tenant shall fail to cancel
     or discharge any mechanic's lien or other lien within the time period as
     provided in Section 17.02, and if any of the foregoing defaults shall
     continue for a period of seven (7) days after notice thereof by Landlord,
     or

               (b)  If Tenant shall be in default in the performance of any of
     the other terms, covenants and conditions of this Lease and such default
     shall not have been remedied within thirty (30) days after notice by
     Landlord to Tenant specifying such default and requiring it to be remedied;
     or where such default reasonably cannot be remedied within such period of
     thirty (30) days, if Tenant shall not have commenced the remedying thereof
     within such period of time and shall not be proceeding with due diligence
     to remedy it,

then Landlord, at Landlord's election, may terminate this Lease on five (5)
days' notice to Tenant, and upon such termination Tenant shall quit and
surrender the Demised Premises to Landlord.

          Section 16.05.  If this Lease shall terminate as provided in this
Article or if Tenant shall be in default in the payment of minimum rent or
additional rent when the same become due and payable, and such default shall
continue for a period of seven (7) days after notice by Landlord to Tenant,

               (a)  Landlord may re-enter and resume possession of the Demised
     Premises and remove all persons and property therefrom either by summary
     dispossess proceedings or by a suitable action or proceeding, at law or in
     equity, or by force or otherwise, without being liable for any damages
     therefor, and

               (b)  Landlord may re-let the whole or any part of the Demised
     Premises for a period equal to, greater or less than the remainder of the
     then term of this Lease, at such rental and upon such terms and conditions
     as Landlord shall deem reasonable to any tenant it may deem suitable and
     for any use and purpose it may deem appropriate.  Landlord shall not be
     liable in any respect for failure to re-let the Demised Premises or, in the
     event of such re-letting, for failure to collect the rent thereunder and
     any sums received by Landlord on a re-letting in excess of the rent
     reserved in this Lease shall belong to Landlord.
<PAGE>

          Section 16.06.  If this Lease shall terminate as provided in this
Article or by summary proceedings (except as to any termination under Section
16.01), Landlord shall be entitled to recover from Tenant as damages, in
addition to arrears in minimum rent and additional rent,

               (a)  an amount equal to (i) all expenses incurred by Landlord in
     recovering possession of the Demised Premises and in connection with the
     re-letting of the Demised Premises, including, without limitation, the cost
     of repairing, renovating or remodeling the Demised Premises, (ii) the cost
     of performing any work required to be done by Tenant under this Lease,
     (iii) the cost of placing the Demised Premises in the same condition as
     that in which Tenant is required to surrender them to Landlord under this
     Lease, and (iv) all brokers' commissions and legal fees incurred by
     Landlord in re-letting the Demised Premises, which amounts set forth in
     this subdivision (a) shall be due and payable by Tenant to Landlord at such
     time or times as they shall have been incurred; and

               (b)  an amount equal to the deficiency between the minimum rent
     and additional rent which would have become due and payable had this Lease
     not terminated and the net amount, if any, of rent collected by Landlord on
     re-letting the Demised Premises.  The amounts specified in this subdivision
     shall be due and payable by Tenant on the several days on which such
     minimum rent and additional rent would have become due and payable had this
     Lease not terminated.  Tenant consents that Landlord shall be entitled to
     institute separate suits or actions or proceedings for the recovery of such
     amount or amounts, and Tenant hereby waives the right to enforce or assert
     the rule against splitting a cause of action as a defense thereto.

               Landlord, at its election, which shall be exercised by the
service of a notice on Tenant, at any time after such termination of this Lease,
may collect from Tenant and Tenant shall pay, in lieu of the sums becoming due,
under the provisions of subdivision (b) of this Section, an amount equal to the
difference between the minimum rent and additional rent which would have become
due and payable had this Lease not terminated (from the date of the service of
such notice to the end of the term of this Lease which had been in force
immediately prior to any termination effected under this Article) and the then
fair and reasonable rental value of the Demised Premises for the same period,
both discounted to the date of the service of such notice at the rate of eight
(8%) percent per annum.

          Section 16.07.  Tenant, for itself and for all persons claiming
through or under it, hereby waives any and all rights which are or may be
conferred upon Tenant by any present or future law to redeem the Demised
Premises after a warrant to dispossess shall have been issued or after judgment
in an action of ejectment shall have been made and entered.
<PAGE>

          Section 16.08.  The words "re-enter" and "re-entry", as used in this
Article, are not restricted to their technical legal meanings.

          Section 16.09.  Landlord shall not be required to give any notice of
its intention to re-enter, except as otherwise provided in this Lease.

          Section 16.10.  In any action or proceeding brought by Landlord
against Tenant, predicated on a default in the payment of minimum rent or
additional rent, Tenant shall not have the right to and shall not interpose any
set-off or counterclaim of any kind whatsoever, other than a claim which would
be legally barred for failure to raise as a counterclaim in such action or
proceeding. If Tenant has any claim, Tenant shall be entitled only to bring an
independent action therefor; and if such independent action is brought by
Tenant, Tenant shall not be entitled to and shall not consolidate it with any
pending action or proceeding brought by Landlord against Tenant for a default in
the payment of minimum rent or additional rent.

                                  ARTICLE 17

                               Mechanic's Liens

          Section 17.01.  If, subject to and notwithstanding Landlord's consent
as required under this Lease, Tenant shall cause any changes, alterations,
additions, improvements, installations or repairs to be made to or at the
Demised Premises or shall cause any labor to be performed or material to be
furnished in connection therewith, neither Landlord nor the Demised Premises,
under any circumstances, shall be liable (except for Landlord's payment
obligations pursuant to Article 38) for the payment of any expense incurred or
for the value of any work done or material furnished, and all such changes,
alterations, additions, improvements, installations and repairs and labor and
material shall be made, furnished and performed upon Tenant's credit alone and
at Tenant's expense, and Tenant shall be solely and wholly responsible to
contractors, laborers, and materialmen furnishing and performing such labor and
material.  Nothing contained in this Lease shall be deemed or construed in any
way as constituting the consent or request of Landlord, express or implied, to
any contractor, laborer or materialman to furnish or to perform any such labor
or material.

          Section 17.02.  If, because of any act or omission (or alleged act or
omission) of Tenant any mechanic's or other lien, charge or order for the
payment of money shall be filed against the Demised Premises or the Building or
Landlord's estate as tenant under any ground or underlying lease (whether or not
such lien, charge or order is valid or enforceable as such), for work claimed to
have been for, or materials furnished to, Tenant, Tenant, at Tenant's expense,
shall cause it to be cancelled or discharged of record by bonding or otherwise
within twenty (20) days after such filing, and Tenant shall indemnify Landlord
against and save Landlord harmless from and shall pay all reasonable costs,
expenses, losses, fines and penalties, including, without limitation, reasonable
attorneys' fees, resulting therefrom.
<PAGE>

                                  ARTICLE 18

             Landlord's and Tenant's Right to Perform Obligations

          Section 18.01.  If Tenant shall default in the performance of any of
the terms or covenants and conditions of this Lease, Landlord, without being
under any obligation to do so and without hereby waiving such default, may
remedy such default for the account and at the expense of Tenant. Any payment
made or expense incurred by Landlord for such purpose (including, but not
limited to, reasonable attorneys' fees) with interest at the maximum legal rate,
shall be deemed to be additional rent hereunder and shall be paid by Tenant to
Landlord on demand, or at Landlord's election, added to any subsequent
installment or installments of minimum rent.

          Section 18.02.  If Landlord shall fail to perform any repair or
maintenance obligation required to be performed by Landlord in the Demised
Premises pursuant to the provisions of this Lease, then Tenant shall give
Landlord written notice (the "Repair Notice") stating the repair or maintenance
obligation which affects the Demised Premises. If Landlord fails to remedy the
condition set forth in the Repair Notice within thirty (30) days after it was
given, then to the extent such repair or maintenance may be performed by Tenant
solely within the Demised Premises, Tenant may perform the same. Landlord shall
reimburse Tenant for the reasonable, actual costs and expenses of performing the
same, within twenty (20) after receipt from Tenant of paid receipts therefor,
together with waivers of liens with respect thereto.

                                  ARTICLE 19

                          Covenant of Quiet Enjoyment

          Landlord covenants that upon Tenant paying the minimum rent and
additional rent and observing and performing all the terms, covenants and
conditions of this Lease on Tenant's part to be observed and performed, Tenant
and all persons claiming through or under Tenant may peaceably and quietly enjoy
the Demised Premises, subject nevertheless to the terms and conditions of this
Lease, and provided, however, that no eviction of Tenant by reason of the
foreclosure of any mortgage now or hereafter affecting the Demised Premises,
whether such termination is by operation of law, by agreement or otherwise,
shall be construed as a breach of this covenant nor shall any action be brought
against Landlord by reason thereof.

                                  ARTICLE 20

                                  Excavation

          In the event that construction is to be commenced or an excavation is
made or authorized for building or other purposes upon land adjacent to the
Building, Tenant shall, if necessary, afford to the person or persons causing or
authorized to commence construction or cause such excavation or to engage in
such other purpose, license to enter upon the Demised Premises for the purpose
of doing such work as shall reasonably be necessary to protect or
<PAGE>

preserve the Building, from injury or damage and to support the Building and any
new structure to be built by proper foundations, pinning and/or underpinning, or
otherwise. However, Landlord shall cause reasonable efforts to be made to have
such work performed in a manner to minimize any interference with the normal
conduct of Tenant's business, provided overtime or premium labor shall not be
required to be employed to perform such work.

                                  ARTICLE 21

                            Services and Equipment

          Section 21.01.  Landlord shall, at its cost and expense:

               (a)  Provide operatorless passenger elevator service Mondays
     through Fridays from 8:00 A.M. to 6:00 P.M., holidays excepted.  A
     passenger elevator will be available at all other times.  A freight
     elevator shall be available Mondays through Fridays, holidays excepted,
     only from 8:00 to 6:00 P.M.  The freight elevator shall be available on a
     "first come, first served" basis during the said days and hours and on a
     reservation "first come, first served" basis other than on said days and
     hours at Landlord's customary charges therefor.

               (b)  Maintain and repair the Building standard heating,
     ventilating and air conditioning system servicing the Demised Premises (the
     "HVAC System") installed by Landlord, except for those repairs which are
     the obligation of Tenant pursuant to Article 6 of this Lease. The HVAC
     System will be operated by Landlord as and when required by law, or for the
     comfortable occupancy of the Demised Premises (as determined by Landlord)
     throughout the year on Mondays through Fridays, holidays excepted, from
     8:00 A.M. to 6:00 P.M.; provided that Tenant shall draw and close the
     draperies or blinds for the windows of the Demised Premises whenever the
     HVAC system is in operation and the position of the sun so requires and
     shall, at all times, cooperate fully with Landlord and abide by all of the
     Rules and Regulations which Landlord may prescribe for the proper
     functioning of the HVAC System.  Landlord agrees to operate the HVAC System
     servicing the Demised Premises in accordance with their design criteria
     unless energy and/or water conservation programs, guidelines or laws and/or
     requirements of public authorities, shall provide for any reduction in
     operations below said design criteria in which case such equipment shall be
     operated so as to provide reduced service in accordance therewith.  Tenant
     expressly acknowledges that some or all windows are or may be hermetically
     sealed and will not open and Landlord makes no representation as to the
     habitability of the Demised Premises at any time the HVAC System is not in
     operation.  Tenant hereby expressly waives any claims against Landlord
     arising out of the cessation of operation of the HVAC System, or the
     suitability of the Demised Premises when the same is not
<PAGE>

     in operation, whether due to normal scheduling or the reasons set forth in
     Section 21.03. Said system is designed to be capable of manufacturing,
     within tolerances normal in first-class office buildings, inside space
     conditions averaging 78 degrees Fahrenheit dry bulb and 50% relative
     humidity when outside conditions are 95 degrees Fahrenheit dry bulb and 75
     degrees Fahrenheit wet bulb, and a temperature of not lower than an average
     of 68 degrees Fahrenheit when outside temperature is 50 degrees Fahrenheit
     or lower. Landlord will not be responsible for the failure of the HVAC
     System if such failure results from the occupancy of the Demised Premises
     by more than an average of one (1) person for each one hundred (100) square
     feet in any separate room or area, and upon a combined lighting and
     standard electrical load not to exceed three (3) watts per usable square
     foot (excluding the Building HVAC), or if Tenant shall install and operate
     machines, incandescent lighting and appliances the total connected
     electrical load in excess of the Building's electrical specifications, as
     determined by Landlord's consulting engineers. If Tenant shall occupy the
     Demised Premises at an occupancy rate of greater than that for which the
     HVAC System was designed, or if the total connected electrical load is in
     excess of the Building's electrical specifications, as determined by
     Landlord's consulting engineers, or if Tenant's partitions shall be
     arranged in such a way as to interfere with the normal operation of the
     HVAC System, Landlord may elect to make changes to the HVAC System or the
     ducts through which it operates required by reason thereof, and the cost
     thereof shall be reimbursed by Tenant to Landlord, as additional rent,
     within twenty (20) days after presentation of a bill therefor. Landlord,
     throughout the term, shall have free access to all mechanical installations
     of Landlord, including but not limited to air-cooling, fan, ventilating and
     machine rooms and electrical closets, and Tenant shall not construct
     partitions or other obstructions that may interfere with Landlord's free
     access thereto, or interfere with the moving of Landlord's equipment to and
     from the enclosures containing said installations. Neither Tenant nor any
     person or entity within Tenant's control shall at any time enter the said
     enclosures or tamper with, adjust, touch or otherwise in any manner affect
     said mechanical installations, except as set forth herein with respect to
     the thermostatic controls within the Demised Premises.

               (c)  Provide Building standard cleaning services in Tenant's
     office space and public portions of the Building, except no services shall
     be performed Saturdays, Sundays and holidays, in accordance with Schedule
     "D" annexed hereto and made part hereof. If, however, any additional
     cleaning of the Demised Premises is to be done by Tenant, it shall be done
     at Tenant's sole expense, in a manner reasonably satisfactory to Landlord
     and no one other than persons approved by Landlord shall be permitted to
     enter the Demised Premises or the Building for such purpose. Tenant, at its
     own cost, may utilize its own employees or outside contractors to perform
     additional cleaning services in the Demised Premises, provided such
     employees or outside contractors do not
<PAGE>

     cause any labor disruption or dispute or violate Landlord's union contracts
     affecting the Building. However, such use of outside contractors shall be
     subject to the right of Landlord to match the costs chargeable by such
     outside contractors, in which event Landlord shall perform such services at
     such cost, to be paid by Tenant within twenty (20) days after being billed
     therefor. Tenant shall pay to Landlord the cost of removal of any of
     Tenant's refuse and rubbish from the Demised Premises and the Building (i)
     to the extent that the same, in any one day, exceeds the average daily
     amount of refuse and rubbish usually attendant upon the use of such Demised
     Premises as offices, as described and included in Landlord's cleaning
     contract for the Building or recommended by Landlord's cleaning contractor,
     and (ii) related to or deriving from the preparation or consumption of food
     or drink, excluding food or drink for normal business use. Bills for the
     same shall be rendered by Landlord to Tenant at such time as Landlord may
     elect and shall be due and payable as additional rent within twenty (20)
     days after the time rendered. Tenant, at Tenant's expense, shall cause the
     Demised Premises to be exterminated from time to time to the satisfaction
     of Landlord and additionally shall cause all portions of the Demised
     Premises used for the storage, preparation, service or consumption of food
     or beverages to be cleaned daily in a manner reasonably satisfactory to
     Landlord, and to be treated against infestation by vermin, rodents or
     roaches, whenever there is evidence of any infestation. Tenant shall not
     permit any person to enter the Demised Premises or the Building for the
     purpose of providing such extermination services, unless such persons have
     been approved by Landlord. If so requested by Landlord, Tenant shall store
     any refuse generated by the consumption of food or beverages on the Demised
     Premises in a cold box or similar facility.

               (d)  Furnish hot and cold water for lavatory and drinking
     purposes.  If Tenant requires, uses or consumes water for any other
     purposes, Landlord may install a meter or meters or other means to measure
     Tenant's water consumption, and Tenant shall reimburse Landlord for the
     cost of the meter or meters and the installation thereof, and shall pay for
     the maintenance of said meter equipment and/or pay Landlord's cost of other
     means of measuring such water consumption by Tenant.  Tenant shall pay to
     Landlord on demand the cost of all water consumed as measured by said meter
     or meters or as otherwise measured, including sewer rents.

               (e)  If Tenant shall require and request any of the foregoing
     services at times other than above provided, and if such request is made at
     least twenty-four (24) hours prior to the time when such additional
     services are required, Landlord will provide them and Tenant shall pay to
     Landlord promptly thereafter the charges therefor at the then Building
     standard rate charged to other tenants in the Building.
<PAGE>

          Section 21.02.  Holidays shall be deemed to mean all federal holidays,
state holidays and Building Service Employees Union Contract holidays.

          Section 21.03.  Landlord reserves the right to interrupt, curtail or
suspend the services required to be furnished by Landlord under this Lease when
necessary by reason of accident, emergency, mechanical breakdown or when
required by any law, order or regulation of any Federal, State, County or
Municipal authority, or for any other cause beyond the control of Landlord.
Landlord shall use due diligence to complete all required repairs or other
necessary work as quickly as possible so that Tenant's inconvenience resulting
therefrom may be for as short a period of time as circumstances will reasonably
permit.  Except as otherwise provided in this Lease, Tenant shall not be
entitled to nor shall Tenant make claim for any diminution or abatement of
minimum rent or additional rent or other compensation, nor shall this Lease or
any of the obligations of Tenant be affected or reduced by reason of such
interruption, curtailment, suspension, work or inconvenience.

          Section 21.04.  Tenant shall reimburse Landlord promptly for the
actual out-of-pocket cost to Landlord of removal from the Demised Premises and
the Building of any refuse and rubbish of Tenant not covered by the Cleaning
Specifications (Schedule D) and Tenant shall pay all bills therefor when
rendered.

          Section 21.05.  If Tenant shall request Landlord to furnish any
services in addition to those hereinabove provided or perform any work not
required under this Lease, and Landlord agrees to furnish and/or perform the
same, Tenant shall pay to Landlord promptly thereafter the charges therefor,
which charges are deemed to be additional rent and payable as such.

          Section 21.06.  Landlord shall provide security in the Building lobby
and Tenant shall have access to the Demised Premises twenty-four (24) hours per
day, seven (7) days per week, subject to emergencies, police power and Article
34.

          Section 21.07.  Landlord represents that the Building facility
equipment is Y2K ready and the Building shall be operated and maintained as a
first-class building similar to other first-class buildings in the vicinity of
the Building.

                                  ARTICLE 22

                                  Escalation

          Section 22.01.  Taxes.  Tenant shall pay to Landlord, as additional
rent, tax escalation in accordance with this Section:

               (a)  Definitions:  For the purpose of this Section, the following
     definitions shall apply:
<PAGE>

                    (i)    The term "Tax Base Factor" shall mean the average of
          the real estate taxes for the Building Project for the periods from
          July 1, 1999 to June 30, 2000, and from July 1, 2000 to June 30, 2001,
          as finally determined.

                    (ii)   The term "The Building Project" shall mean the parcel
          of Land described in Schedule B of this Lease with all improvements
          erected thereon.

                    (iii)  The term "Comparative Tax Year" shall mean the New
          York City real estate tax year commencing on July 1, 2001 and each
          subsequent New York City real estate tax year.  If the present use of
          July 1-June 30 New York City real estate tax year shall hereafter be
          changed, then such changed tax year shall be used with appropriate
          adjustment for the transition.

                    (iv)   The term "Real Estate Taxes" shall mean the total of
          all taxes and special or other assessments and charges of any Special
          Business Improvement District levied, assessed or imposed at any time
          by any governmental authority: (a) upon or against the Building
          Project, and (b) in connection with the receipt of income or rents
          from the Building Project to the extent that same shall be in lieu of
          all or a portion of any of the aforesaid taxes or assessments, or
          additions or increases thereof. Income, franchise, transfer,
          inheritance, corporate, mortgage recording or capital stock taxes of
          Landlord, or penalties or interest thereon, shall be excluded from
          "Real Estate Taxes" for the purposes hereof. If, due to a future
          change in the method of taxation or in the taxing authority, or for
          any other reason, a franchise, income, transit, profit or other tax or
          governmental imposition, however designated, shall be levied against
          Landlord in substitution in whole or in part for the Real Estate
          Taxes, or in lieu of or addition to or increase of Real Estate Taxes,
          then such franchise, income, transit, profit or other tax or
          governmental imposition shall be included within "Real Estate Taxes."
          Tenant acknowledges that the Tax Escalation Payment (as hereinafter
          defined) constitutes a method by which Landlord is seeking to
          compensate for increases in expenses and that the Tax Escalation
          Payment shall be calculated and paid by Tenant to Landlord whether or
          not Real Estate Taxes have then been paid by Landlord.

                    (v)    The term "the Percentage" for purposes of computing
          tax escalation, shall mean 8.573%.
<PAGE>

               (b)  (i)    In the event that the Real Estate Taxes payable for
          any Comparative Tax Year shall exceed the Tax Base Factor, Tenant
          shall pay to Landlord, as additional rent for such Comparative Tax
          Year, an amount for tax escalation ("Tax Escalation Payment")equal to
          the Percentage of the excess. Before or after the start of each
          Comparative Tax Year, Landlord shall furnish to Tenant a statement of
          the Tax Escalation Payment payable for such Comparative Tax Year,
          together with a copy of the tax bill. Tenant shall make its aforesaid
          Tax Escalation Payment to Landlord, in installments in the same manner
          and not later than thirty (30) days prior to the last date that Real
          Estate Taxes are payable by Landlord to the governmental authority. If
          a statement is furnished to Tenant after the commencement of the
          Comparative Tax Year in respect of which such statement is rendered,
          Tenant shall, within twenty (20) days thereafter, pay to Landlord an
          amount equal to those installments of the total Tax Escalation Payment
          then due. If, during the term of this Lease, Real Estate Taxes are
          required to be paid, in full or in monthly or other installments, on
          any other date or dates than as presently required, or if Landlord
          shall be required to make monthly deposits of Real Estate Taxes to the
          holder of any mortgage, then Tenant's Tax Escalation Payment(s) shall
          be correspondingly adjusted so that the same are due to Landlord in
          corresponding installments not later than thirty (30) days prior to
          the last date on which the applicable installment of such Real Estate
          Taxes shall be due and payable to the governmental authority or such
          mortgagee.

                    (ii)   If in any tax certiorari proceeding regarding Real
          Estate Taxes payable for any Comparative Tax Year or in otherwise
          establishing such taxes, Landlord has incurred expenses for legal
          and/or consulting services rendered in applying for, negotiating or
          obtaining a reduction of the assessment upon which the Real Estate
          Taxes are predicated, Tenant shall pay an amount equal to the
          Percentage of such expenses.

                    (iii)  The statements of the Tax Escalation Payment to be
          furnished by Landlord as provided above shall constitute a final
          determination as between Landlord and Tenant of the Tax Escalation
          Payment for the periods represented thereby, except for mathematical
          error in computation.
<PAGE>

                    (iv)   In no event shall the fixed minimum rent under this
          Lease be reduced by virtue of this Section 22.01.

                    (v)    Upon the date of any expiration or termination of
          this Lease, whether the same be the date hereinabove set forth for the
          expiration of the term or any prior or subsequent date, a
          proportionate share of the Tax Escalation Payment for the Comparative
          Tax Year during which such expiration or termination occurs shall
          immediately become due and payable by Tenant to Landlord, if it was
          not theretofore already billed and paid, or due and payable by
          Landlord to Tenant if the amount paid by Tenant exceeded such
          proportionate share. The said proportionate share shall be based upon
          the length of time that this Lease shall have been in existence during
          such Comparative Tax Year. Prior to or promptly after said expiration
          or termination, Landlord shall compute the Tax Escalation Payment due
          from or owed to Tenant, as aforesaid and Tenant shall promptly pay
          Landlord any amount unpaid. If Landlord shall receive a refund or a
          tax credit of any amount of Real Estate Taxes for any Comparative Tax
          Year for which Tenant has made a payment, Landlord shall pay to Tenant
          within fifteen (15) days of its receipt of such refund the Percentage
          of any such refund, less the Percentage of any legal fees and other
          expenses provided for in Section 22.01(b)(ii) to the extent the same
          have not theretofore been paid by Tenant.

                    (vi)   Landlord's and Tenant's obligations to make the
          adjustments referred to in subdivision (v) above shall survive any
          expiration or termination of this Lease.

                    (vii)  Any delay or failure of Landlord in billing any Tax
          Escalation Payment hereinabove provided shall not constitute a waiver
          of or in any way impair the continuing obligation of Tenant to pay
          such Tax Escalation Payment hereunder.

                    (viii) Notwithstanding any language to the contrary
          contained in this Lease, Landlord and Tenant agree that for the
          purposes of this Section 22.01, Real Estate Taxes and Tax Escalation
          Payments shall be calculated without regard to any deductions,
          credits, abatements, or deferral of Real Estate Taxes which Landlord
          may receive pursuant to Sections
<PAGE>

          11.256 through 11-267 of the Administrative Code of the City of New
          York, authorized by Title 2-D of Article 4 of the New York Real
          Property Tax Law and any and all rules and regulations promulgated
          thereunder (herein collectively called the "ICIP Program").

          Section 22.02.  Porter's Wage Rate.  Tenant shall pay to the Landlord,
as additional rent, a porter's wage rate escalation in accordance with this
Section:

               (a)  For the purpose of this Section, the following definitions
     shall apply:

                    (i)  "Wage Rate" shall mean the minimum regular hourly rate
          of wages in effect as of January 1st of each year (whether paid by
          Landlord or any contractor employed by Landlord) computed as paid over
          a forty hour week to Porters in Class A office buildings pursuant to
          an Agreement between Realty Advisory Board on Labor Relations,
          Incorporated, or any successor thereto, and Local 32B-32J of the
          Building Service Employees International Union, AFL-CIO, or any
          successor thereto; and provided, however, that if there is no such
          agreement in effect prescribing a wage rate for Porters, computations
          and payments shall thereupon be made upon the basis of the regular
          hourly wage rate actually payable in effect as of January 1st of each
          year, and provided, however, that if in any year during the term, the
          regular employment of Porters shall occur on days or during the hours
          when overtime or other premium pay rates are in effect pursuant to
          such Agreement, then the term "hourly rate of wages" as used herein
          shall be deemed to mean the average hourly rate for the hours in a
          calendar week during which Porters are regularly employed (e.g., if
          pursuant to an agreement between Realty Advisory Board and the Local
          the regular employment of Porters for forty hours during a calendar
          week is at a regular hourly wage rate of $3.00 for the first thirty
          hours, and premium or overtime hourly wage rate of $4.50 for the
          remaining ten hours, then the hourly rate of wages under this Article
          during such period shall be the total weekly rate of $135.00 divided
          by the total number of regular hours of employment, forty or $3.375).
          Notwithstanding the foregoing, if at any time such hourly wage rate is
          different for new hire and old hire Porters, then thereafter such
          hourly wage rate shall be based on the weighted average of the wage
          rates for the different classifications of Porters.
<PAGE>

                    (ii)   "Base Wage Rate" shall mean the Wage Rate in effect
          on January 1, 2000.

                    (iii)  The term "Porters" shall mean that classification of
          non-supervisory employees employed in and about the Building who
          devote a major portion of their time to general cleaning, maintenance
          and miscellaneous services essentially of a non-technical and non-
          mechanical nature and are the type of employees who are presently
          included in the classification of "Class A-Others" in the Commercial
          Building Agreement between the Realty Advisory Board and the aforesaid
          Union.

                    (iv)   The term "minimum regular hourly rate of wages" shall
          not include any payments for fringe benefits or adjustments of any
          kind.

                    (v)    The term "Multiplication Factor" shall mean 75,000.

               (b)  If the Wage Rate for any calendar year during the term shall
     be increased above the Base Wage Rate, then Tenant shall pay, as additional
     rent, an amount equal to the product obtained by multiplying the
     Multiplication Factor by 100% of the number of cents (including any
     fraction of a cent) by which the Wage Rate is greater than the Base Wage
     Rate, such payment to be made in equal one-twelfth (1/12th) monthly
     installments commencing with the first monthly installment of minimum rent
     falling due on or after the effective date of such increase in Wage Rate
     (payable retroactive from said effective date) and continuing thereafter
     until a new adjustment shall have become effective in accordance with the
     provisions of this Article. Landlord shall give Tenant notice of each
     change in Wage Rate which will be effective to create or change Tenant's
     obligation to pay additional rent pursuant to the provisions of this
     Section 22.02 and such notice shall contain Landlord's calculation in
     reasonable detail and certified as true by an authorized partner of
     Landlord or of its managing agent, of the annual rate of additional rent
     payable resulting from such increase in Wage Rate. Such amounts shall be
     prorated for any partial calendar years during the term.

               (c)  Every notice given by Landlord pursuant to Section 22(b)
     hereof shall be conclusive and binding upon Tenant, except for manifest
     error.

               (d)  The "Wage Rate" is intended to be a substitute comparative
     index of economic costs and does not necessarily reflect the actual
<PAGE>

     costs of wages or other expenses of operating the Building. The Wage Rate
     shall be used whether or not the Building is a Class A office building and
     whether or not Porters are employed in the Building and without regard to
     whether such employees are members of the Union referred to in subsection
     (a) hereof.

                                  ARTICLE 23

                                  Electricity

          Section 23.01.

               (a)  Landlord shall provide electricity to the Demised Premises
     on a submetering basis from the existing risers and switches on the floor.
     Tenant's consumption of electricity shall be measured by one independent
     time of day (or use) submeter furnished and installed by Landlord, at the
     cost of Tenant, and read by Landlord. If Tenant shall require electricity
     exceeding the available service capacity, any additional risers, feeders
     and similar electrical equipment which may be required, shall be installed
     by Landlord, at the expense of Tenant, to and for the use of Tenant in the
     Demised Premises during the term hereof. Any riser(s) shall terminate at a
     disconnect switch to be located at a point designated by Landlord in
     electrical closet(s) on the floor of the Demised Premises. Such disconnect
     switch shall be the sole source from which Tenant is to obtain electricity.
     Such submeter shall at all times be maintained by Tenant, at its expense,
     unless damaged due to the negligence of Landlord, its agents, employees or
     contractors. Tenant covenants and agrees to purchase electric power from
     Landlord or Landlord's designated agent at charges, terms and rates set,
     from time to time, during the term of this Lease by Landlord but not more
     than those specified in the service classification in effect from time to
     time pursuant to which Landlord then purchases electric current from the
     Electric Service Provider or Alternate Service Provider (as said terms are
     hereinafter defined), as the case may be, plus a fee equal to five (5%)
     percent of such charges, representing agreed upon administrative and
     overhead costs to Landlord. Bills therefor shall be rendered monthly or at
     such other times as Landlord may elect together with copies of the submeter
     printouts showing the totalized demand for the meter and copies of the
     applicable public utility rate schedule pursuant to which Landlord is then
     purchasing electricity for the Building, and the amount, as computed from
     such meter, shall be deemed to be, and be paid as, additional rent, within
     ten (10) days thereafter, without any set-off or deduction. If any tax is
     imposed upon Landlord's receipt from the sale or resale of electric energy
     to Tenant by any federal, state or municipal authority, Tenant covenants
     and agrees that, where permitted by law, Tenant's pro rata share of such
     taxes shall be passed on to, and included in the bill of, and paid by,
     Tenant to Landlord.
<PAGE>

               (b)  Landlord has advised Tenant that presently Con Edison
     ("Electric Service Provider") is the utility company selected by Landlord
     to provide electricity service for the Building. Notwithstanding the
     foregoing, if permitted by law, Landlord shall have the right at any time
     and from time to time during the term of this Lease to either contract for
     service from a different company or companies providing comparable
     electricity service at comparable or lower rates (each such company shall
     hereinafter be referred to as an "Alternate Service Provider") or continue
     to contract for service from the Electric Service Provider.

               (c)  Tenant shall cooperate with Landlord, the Electric Service
     Provider, and any Alternate Service Provider at all times and, as
     reasonably necessary, shall allow Landlord, Electric Service Provider, and
     any Alternate Service Provider reasonable access to the Building's electric
     lines, feeders, risers, wiring, and any other machinery within the Demised
     Premises.

          Section 23.02.  Landlord shall not be liable in any way for any loss,
damage or expense that Tenant may sustain or incur by reason of or any failure,
change, interruption or defect in the supply or character of electric energy
furnished to the Demised Premises by reason of any requirement, act or omission
of the Electric Service Provider or Alternate Service Provider (as said terms
are hereinafter defined) serving the Building with electricity and no such
failure, change, interruption or defect shall constitute an act of constructive
eviction, in whole or in part, or entitle Tenant to any abatement of minimum
rent or additional rent or relieve Tenant of its obligations under this Lease.
Tenant shall furnish and install, at its sole cost and expense, all lighting
fixtures, tubes, lamps, bulbs, ballasts and outlets relating to Tenant's
electrical equipment.

          Section 23.03.  Tenant's connected electrical load in the Demised
Premises, including lighting, shall not at any time exceed the capacity of any
of the electrical conductors and equipment in or servicing the Demised Premises
which capacity Landlord represents to be six (6) watts per usable square foot
(excluding the Building HVAC). In order to insure that such capacity is not
exceeded and to avert possible adverse effect upon the Building electric
service, Tenant shall not, without Landlord's prior consent in each instance,
make any alteration or addition to the electric system of the Demised Premises
existing on the Commencement Date, nor connect any additional fixtures,
appliances or equipment that would exceed the electrical capacity of the Demised
Premises represented by Landlord. Should Landlord grant such consent, all
additional risers or other equipment required therefor shall be provided by
Landlord and the cost thereof shall be paid by Tenant.

          Section 23.04.  Landlord reserves the right to discontinue furnishing
electric energy at any time, whether or not Tenant is in default under this
Lease, upon not less than thirty (30) days' notice to Tenant, provided Landlord
discontinues furnishing electricity to all other tenants in the Building. If
Landlord exercises such right of discontinuance, this Lease
<PAGE>

shall continue in full force and effect and shall be unaffected thereby, except
only that, from and after the effective date of such discontinuance, Landlord
shall not be obligated to furnish electric energy to Tenant. If Landlord so
elects to discontinue furnishing electric energy to Tenant, Tenant shall arrange
to obtain electric energy directly from the public utility company furnishing
electric service to the Building. Notwithstanding the foregoing, Landlord shall
not discontinue furnishing electric energy until Tenant is able to obtain such
electric energy directly from said public utility. Such electric energy may be
furnished to Tenant by means of the then existing Building system feeders,
risers and wiring to the extent that they are available, suitable and safe for
such purposes. All meters and additional panel boards, feeders, risers, wiring
and other conductors and equipment which may be required to obtain electric
energy directly from such public utility company, and which are to be located
within the Demised Premises, shall be installed by Landlord at its expense if
such discontinuance was voluntary, or installed by Landlord at Tenant's expense
if such discontinuance was required by law or the utility company. Thereafter,
all of such equipment shall be maintained by Tenant at its expense.

                                  ARTICLE 24

                                    Broker

          Landlord and Tenant covenant and represent that the sole brokers who
negotiated and brought about this transaction were Cushman Realty Corporation,
CRF Partners, Inc. and Cohen Brothers Realty Corporation.  Landlord agrees to
pay a commission therefor to Cushman Realty Corporation and Cohen Brothers
Realty Corporation as per separate agreements and Landlord shall not be
responsible for any separate payment to CRF Partners, Inc. .  Landlord and
Tenant agree to hold the other harmless against any claims for a brokerage
commission arising out of a breach by the other of the representations contained
in this Article.

                                  ARTICLE 25

                        Subordination and Ground Lease

          Section 25.01.  This Lease is subject and subordinate to (a) all
ground and underlying leases on the Land and/or Building now or hereafter
existing, and (b) to all mortgages which may now or hereafter affect any such
ground and underlying leases or the Land and/or the Building, and to all
renewals, modifications, amendments, consolidations, replacements or extensions
of any of the foregoing. This clause shall be self-operative and no further
instrument of subordination shall be required. However, in confirmation of such
subordination, Tenant, at any time and from time to time, shall execute
promptly, and within fifteen (15) days of such request, any certificate and
document that Landlord may reasonably request which reasonably evidences such
subordination. Landlord, within forty-five (45) days from the date hereof,
agrees to obtain from Credit Suisse First Boston Mortgage Capital, LLC, the
holder of the existing mortgage which is a lien on the Building Project, an
agreement (the "non-disturbance and attornment agreement") providing in
substance that Tenant's possession
<PAGE>

of and rights in the Demised Premises and under this Lease shall remain
undisturbed, so long as Tenant is not in default under the provisions of this
Lease, after any notice and the expiration of any applicable periods of grace,
and provided Tenant agrees in said instrument to attorn to such mortgagee as its
landlord under this Lease. If a fully executed and acknowledged original copy of
such non-disturbance and attornment agreement is not delivered to Tenant within
such forty-five (45) day period, Tenant, as its sole remedy for Landlord's
failure to obtain the non-disturbance and attornment agreement, may by notice
given within fifteen (15) days after the expiration of such forty-five (45) day
period, terminate this Lease on a date specified in such notice which shall not
be later than thirty (30) days after the date of said notice, unless prior to
such termination date all such copies are delivered to Tenant or Tenant elects
to rescind such notice. In the event of such termination, neither Landlord nor
Tenant shall have any further liability to each other except that Landlord shall
return to Tenant all moneys given to Landlord upon the execution of this Lease.
Concurrently with the execution of this Lease, Tenant has executed a non-
disturbance and attornment agreement with respect to such mortgagee. It is
further agreed that this Lease shall not be subject and subordinate to and
Tenant shall not be required to attorn to any mortgages or any ground or
underlying leases which may hereafter affect the Building Project, unless the
holder of each such mortgage or lessor under each such lease executes such non-
disturbance and attornment agreement in the then customary form of such
mortgagee or lessor.

          Section 25.02.  (a)  The Tenant covenants and agrees that if by reason
     of a default under any underlying lease, or under any mortgage, such
     underlying lease and the leasehold estate of the Landlord in the Demised
     Premises is terminated, or the Land and/or the Building are foreclosed upon
     or transferred in lieu of a foreclosure, the Tenant will attorn to the then
     holder of the reversionary interest in the premises demised by this Lease
     or the foreclosure purchaser or transferee in lieu of foreclosure, and will
     recognize such holder, purchaser or transferee as the Tenant's Landlord
     under this Lease, unless, subject to any non-disturbance agreement, the
     lessor under such underlying lease or the holder of any such mortgage
     shall, in any proceeding to terminate such underlying lease or foreclose
     such mortgage, elects to terminate this Lease and the rights of Tenant
     hereunder provided, however, the holder of the reversionary interest or the
     foreclosure purchaser or transferee in lieu of foreclosure shall not be (i)
     liable for any act or omission or negligence of Landlord under this Lease;
     (ii) subject to any counterclaim, defense or offset, not expressly provided
     for in this Lease and asserted with reasonable promptness which theretofore
     shall have accrued to Tenant against Landlord; (iii) obligated to perform,
     undertake or complete any work in the Demised Premises or to prepare it for
     occupancy; (iv) bound by any previous modification or amendment of this
     Lease or by any previous prepayment of more than one (1) month's rent,
     unless such modification or prepayment shall have been approved in writing
     by the holder of such Mortgage; (v) obligated to repair the Demised
     Premises, or the Building, or any part thereof, in the event of any damage
     beyond such repair as can reasonably be accomplished
<PAGE>

     from the net proceeds of insurance actually made available to the then
     holder of the reversionary interest or the foreclosure purchaser or
     transferee in lieu of foreclosure; (vi) obligated to repair the Demised
     Premises or the Building, or any part thereof, in the event of partial
     condemnation of the Demised Premises or the Building; (vii) required to
     account for any security deposit of Tenant unless actually delivered to
     such holder, purchaser or transferee by Landlord; (viii) bound by any
     obligation to make any payment to Tenant or grant any credits, except for
     services, repairs, maintenance and restoration provided for under this
     Lease to be performed by Landlord after the date of attornment; or (ix)
     responsible for any monies owing by Landlord to Tenant. Nothing contained
     in this subparagraph shall be construed to impair any right otherwise
     exercisable by any such holder, purchaser or transferee. Tenant agrees to
     execute and deliver, at any time and from time to time, upon the request of
     the Landlord of or the lessor under any such underlying lease or the holder
     of any such mortgage any instrument which may be necessary or appropriate
     to evidence such attornment. The Tenant further waives the provisions of
     any statute or rule or law now or hereafter in effect which may give or
     purport to give Tenant any right of election to terminate this Lease or to
     surrender possession of the premises demised hereby in the event any
     proceeding is brought by the lessor under any underlying lease or the
     holder of any such mortgage to terminate the same, and agrees that, subject
     to any non-disturbance agreement, unless and until any such lessor or
     holder, in connection with any such proceeding, shall elect to terminate
     this Lease and the rights of Tenant hereunder, this Lease shall not be
     affected in any way whatsoever by any such proceeding.

               (b)  Upon Tenant's receipt of a written notice from the lessor
     under any underlying lease or the holder of any such mortgage to the effect
     that (i) the lessor of said underlying lease or the holder of any such
     mortgage is entitled to send a notice to the Landlord, as tenant under said
     underlying lease, terminating said lease, or such holder is entitled to
     performance by Tenant under the Lease, and (ii) the Tenant should pay the
     minimum rent and additional rent thereafter due and payable under this
     Lease to said lessor or the holder of any such mortgage at a place
     designated in such notice, Tenant shall pay such minimum rent and
     additional rent to said lessor under said underlying lease or the holder of
     any such mortgage at such designated place until such time as said lessor
     or holder shall notify Tenant that Landlord is no longer in default under
     said underlying lease or such mortgage and that Tenant may resume paying
     all minimum rent and additional rent thereafter due and payable under this
     Lease to Landlord. Tenant shall have no liability to the Landlord for
     paying any minimum rent or additional rent to said lessor under the
     underlying lease or holder of any such mortgage or otherwise acting in
     accordance with the provisions of any notice sent to it under this
     paragraph and shall be relieved of its obligations to pay Landlord any
     minimum rent or additional rent under this
<PAGE>

     Lease to the extent such payments are made to said lessor under the
     underlying lease.

          Section 25.03.  In the event of any act or omission by Landlord which
would give Tenant the right to terminate this Lease or to claim a partial or
total eviction, pursuant to the terms of this Lease, if any, Tenant will not
exercise any such right until:

               (a)  it has given a written notice to cure (concurrently with any
     notice given to Landlord), regarding such act or omission to the holder of
     any mortgage and to the landlord of any ground or underlying lease, whose
     names and addresses shall previously have been furnished to Tenant,
     addressed to such holder and landlord at the last addresses so furnished,
     and

               (b)  a reasonable period of time (not to exceed the period in
     this Lease or the ground lease or the mortgage, as the case may be) for
     remedying such act or omission shall have elapsed following such giving of
     notice and the expiration of any grace period applicable thereto in favor
     of Landlord hereunder, during which such holder and landlord, or any of
     them, with reasonable diligence, following the giving of such notice, shall
     not have commenced and is or are not continuing to remedy such act or
     omission or to cause the same to be remedied.

          Section 25.04.  If, in connection with obtaining financing for the
Building, or of Landlord's interest in any ground or underlying lease, a
banking, insurance or other recognized institutional lender shall request
modifications in this Lease as a condition to such financing, Tenant will not
withhold, delay or defer its consent thereto and its execution and delivery of
such modification agreement, provided that such modifications do not increase
the obligations (including the monetary obligations) of Tenant hereunder or
adversely affect the leasehold interest hereby created or Tenant's use and
enjoyment of the Demised Premises or Tenant's rights or reduce the Building's
services or Landlord's obligations.

          Section 25.05.  Landlord represents that the only mortgage covering
the Land and Building is the existing mortgage held by Credit Suisse First
Boston Mortgage Capital, LLC, that there are no defaults thereunder by Landlord,
and that there is no present ground or underlying lease covering the Land and
Building.

                                  ARTICLE 26

                             Estoppel Certificate

          Landlord and Tenant shall at any time, and from time to time, within
ten (10) business days after so requested by the other execute, acknowledge and
deliver to the other , a statement addressed to the other or its designee or the
holder of any mortgage encumbering the Land and/or Building (a) certifying that
this Lease is unmodified and in full force and effect
<PAGE>

(or, if there have been modifications, that the same is in full force and effect
as modified and stating the modifications), (b) stating the dates to which the
minimum rent and additional rent have been paid, (c) stating whether or not
there exists any default by the other under this Lease, and, if so, specifying
each such default, and (d) such other information as may be required by
Landlord, Tenant or any mortgagee, it being intended that any such statement may
be relied upon by Landlord, Tenant, by any mortgagee or prospective mortgagee of
any mortgage affecting the Building or the leasehold estate under any ground or
underlying lease affecting the land described in Schedule B and/or Building and
improvements thereon, or may be relied upon by the landlord under any such
ground or underlying lease or a purchaser of Lessee's estate under any such
ground or underlying lease or any interest therein, or any assignee of Tenant.

                                  ARTICLE 27

                             Waiver of Jury Trial

          Tenant hereby waives the right to trial by jury in any summary
proceeding that may hereafter be instituted against it or in any action or
proceeding that may be brought by Landlord on matters which are connected with
this Lease, or any of its provisions or Tenant's use or occupancy of the Demised
Premises, including any claims for injury or damage, or any emergency or other
statutory remedy with respect thereto.

                                  ARTICLE 28

                             Surrender of Premises

          Section 28.01.  Upon the expiration or other termination of the term
of this Lease, Tenant shall quit and surrender the Demised Premises, vacant,
broom clean, in good order and condition, ordinary wear and tear and damage by
fire or other casualty excepted, and shall remove  all its personal property
therefrom.  Tenant's obligation to observe or perform this covenant shall
survive the expiration or other termination of the term of this Lease.

          Section 28.02.  In the event Tenant shall remain in possession of the
Demised Premises after the expiration or other termination of the term of this
Lease, such holding over shall not constitute a renewal or extension of this
Lease.  Landlord, may, at its option, elect to treat Tenant as one who is not
removed at the end of the term, and thereupon be entitled to all of the remedies
against Tenant provided by law in that situation or Landlord may elect to
construe such holding over as a tenancy from month-to-month, subject to all of
the terms and conditions of this Lease, except as to the duration thereof, and
the minimum rent shall be due, in either of such events, at a monthly rental
rate equal to two (2) times the monthly installment of minimum rent which would
otherwise be payable for such month, together with any and all additional rent.
Tenant shall also be responsible for and hereby indemnifies Landlord against any
claims made by any succeeding tenant or prospective tenant founded upon Tenant's
delay in surrendering the Demised Premises to Landlord.
<PAGE>

                                  ARTICLE 29

                             Rules and Regulations

          Section 29.01.  Tenant, its servants, employees, agents, visitors and
licensees shall observe faithfully and comply with the rules and regulations set
forth in Schedule "C" attached hereto and made a part hereof.  Landlord shall
have the right from time to time during the term of this Lease to make
reasonable changes in and additions to the rules thus set forth provided such
changes and additions are applicable to all other office tenants in the
Building.  All rules and regulations shall be enforced in a non-discriminatory
manner.

          Section 29.02.  Any failure by Landlord to enforce any rules and
regulations now or hereafter in effect, either against Tenant or any other
tenant in the Building, shall not constitute a breach hereunder or waiver of any
such rules and regulations.

                                  ARTICLE 30

                    Successors and Assigns and Definitions

          Section 30.01.  The covenants, conditions and agreements contained in
this Lease shall bind and enure to the benefit of Landlord and Tenant and their
respective distributees, legal representatives, successors and, except as
otherwise provided herein, their assigns.

          Section 30.02.  The term "Landlord" as used in this Lease, so far as
the covenants and agreements on the part of Landlord are concerned shall be
limited to mean and include only the owner or owners at the time in question of
the tenant's estate under any ground or underlying lease covering the Land
described in Schedule B hereto annexed and/or the fee title of Landlord covering
the Land and/or the Building and improvements thereon. In the event of any
assignment or assignments of such tenant's estate or transfer of such title,
Landlord herein named (and in case of any subsequent assignment or transfer, the
then assignor or transferor) shall be automatically freed and relieved from and
after the date of such assignment or transfer of all personal liability as
respects to performance of any of Landlord's covenants and agreements thereafter
to be performed, and such assignee or transferee shall be bound by all of such
covenants and agreements; it being intended that Landlord's covenants and
agreements shall be binding on Landlord, its successors and assigns only during
and in respect of their successive periods of such ownership.

          However, in any event, the members in Landlord shall not have any
personal liability or obligation by reason of any default by Landlord under any
of Landlord's covenants and agreements in this Lease.  In case of such default,
Tenant will look only to Landlord's estate, as tenant, under such ground or
underlying lease and/or its interest in the Land and/or Building, to recover any
loss or damage resulting therefrom; and Tenant shall have no right to
<PAGE>

nor shall Tenant assert any claim against nor have recourse to Landlord's other
property or assets to recover such loss or damage.

          Section 30.03.  All pronouns or any variation thereof shall be deemed
to refer to masculine, feminine or neuter, singular or plural as the identity of
the person or persons may require; and if Tenant shall consist of more than one
(1) person, the obligations of such persons, as Tenant, under this Lease, shall
be joint and several.

          Section 30.04.  The definitions contained in Schedule E annexed hereto
are hereby made a part of this Lease.

                                  ARTICLE 31

                                    Notices

          Any notice, statement, certificate, request, approval, consent or
demand required or permitted to be given under this Lease shall be in writing
sent by registered or certified mail (or reputable, commercial overnight courier
service) return receipt requested, addressed, as the case may be, to Landlord,
at 750 Lexington Avenue, New York, New York 10022, and to Tenant prior to its
occupancy of the Demised Premises at its address hereinbefore first set forth,
and after its occupancy at the Demised Premises with copies to Chief Financial
Officer and General Counsel, CMGI, Inc., 100 Brickstone Square, Andover,
Massachusetts 01810, or to such other addresses as Landlord or Tenant
respectively shall designate in the manner herein provided. Such notice,
statement, certificate, request, approval, consent or demand shall be deemed to
have been given on the date when mailed, as aforesaid, or on the date of
delivery by overnight courier.

                                  ARTICLE 32

                          No Waiver; Entire Agreement

          Section 32.01.  The specific remedies to which Landlord may resort
under the provisions of this Lease are cumulative and are not intended to be
exclusive of any other remedies or means of redress to which Landlord may be
lawfully entitled in case of any breach or threatened breach by Landlord of any
of the terms, covenants and conditions of this Lease. The failure of Landlord or
Tenant to insist upon the strict performance of any of the terms, covenants and
conditions of this Lease, or to exercise any right or remedy herein contained,
shall not be construed as a waiver or relinquishment for the future of such
term, covenant, condition, right or remedy. A receipt by Landlord of minimum
rent or additional rent with knowledge of the breach of any term, covenant or
condition of this Lease shall not be deemed a waiver of such breach. This Lease
may not be changed or terminated orally. In addition to the other remedies in
this Lease provided, Landlord shall be entitled to seek to restrain by
injunction, the violation or attempted or threatened violation of any of the
terms, covenants and conditions of this Lease or to a decree, any court having
jurisdiction in the matter, compelling
<PAGE>

performance of any such terms, covenants and conditions.

          Section 32.02.  No receipt of monies by Landlord from Tenant, after
any re-entry or after the cancellation or termination of this Lease in any
lawful manner, shall reinstate the Lease; and after the service of notice to
terminate this Lease, or after commencement of any action, proceeding or other
remedy, Landlord may demand, receive and collect any monies due, and apply them
of account of Tenant's obligations under this Lease but without in any respect
affecting such notice, action, proceeding or remedy, except that if a money
judgment is being sought in any such action or proceeding, the amount of such
judgment shall be reduced by such payment.

          Section 32.03.  If Tenant is in arrears in the payment of minimum rent
or additional rent, Tenant waives its right, if any, to designate the items in
arrears against which any payments made by Tenant are to be credited and
Landlord may apply any of such payments to any such items in arrears as
Landlord, in its sole discretion, shall determine, irrespective of any
designation or request by Tenant as to the items against which any such payments
shall be credited.

          Section 32.04.  No payment by Tenant nor receipt by Landlord of a
lesser amount than may be required to be paid hereunder shall be deemed to be
other than on account of any such payment, nor shall any endorsement or
statement on any check or any letter accompanying any check tendered as payment
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
payment due or pursue any other remedy in this Lease provided.

          Section 32.05.  This Lease and the Schedules annexed hereto constitute
the entire agreement between Landlord and Tenant referable to the Demised
Premises, and all prior negotiations and agreements are merged herein.

          Section 32.06.  If any term or provision of this Lease or the
application thereof to any person or circumstance shall, to any extent, be
invalid or unenforceable, the remainder of this Lease, or the application of
such term or provision to persons or circumstances other than those as to which
it is held invalid or unenforceable, shall not be affected thereby, and each
term and provision of this Lease shall be valid and be enforced to the fullest
extent permitted by law.

                                  ARTICLE 33

                                   Captions

          The captions of Articles in this Lease are inserted only as a matter
of convenience and for reference and they in no way define, limit or describe
the scope of this Lease or the intent of any provision thereof.
<PAGE>

                                  ARTICLE 34

                             Inability to Perform

          If the performance or observance by Landlord or Tenant of any of the
terms, covenants and conditions of this Lease on the part of Landlord or Tenant
to be performed shall be delayed by reason of unavoidable delays (as hereinafter
defined), then the time for the performance or observance thereof shall be
extended for the period of time as Landlord or Tenant shall have been so
delayed, provided Tenant shall continue, notwithstanding unavoidable delays, to
be obligated to pay minimum rent and additional rent without abatement.

          Notwithstanding anything to the contrary contained in this Lease, if
Landlord shall fail to provide services or perform work or repairs, as provided
in this Lease (collectively, an "Interruption"), and such Interruption shall
materially impair the customary operation of Tenant's business in all or any
part of the Demised Premises (other than a de minimis part), and if (i) such
Interruption shall continue for a period in excess of thirty (30) consecutive
days following receipt by Landlord of notice from Tenant describing such
Interruption and (ii) such Interruption shall not have been caused by an act or
omission in violation of this Lease by or the negligence of Tenant, or of Tenant
agents, servants, employees or contractors (an Interruption that satisfied all
of the foregoing conditions being referred to hereinafter as a "Material
Interruption"), then Tenant shall be entitled to an abatement of the minimum
rent and escalation rent payable under Article 22 (such abatement to be prorated
if only a part of the Demised Premises shall be so affected by such Material
Interruption),which shall begin on the 31st consecutive day of such Material
Interruption and shall end upon the date such Material Interruption has been
terminated.

          The words "unavoidable delays", as used in this Lease shall mean (a)
the enactment of any law or issuance of any governmental order, rule or
regulation (i) prohibiting or restricting performance of work of the character
required to be performed by Landlord under this Lease, or (ii) establishing
rationing or priorities in the use of materials, or (iii) restricting the use of
labor, and (b) strikes, lockouts, acts of God, inability to obtain labor or
materials, enemy action, civil commotion, fire, unavoidable casualty or other
similar types of causes beyond the reasonable control of Landlord, other than
financial inability.

                                  ARTICLE 35

                        No Representations by Landlord

          Neither Landlord nor any agent or employee of Landlord has made any
representation whatsoever with respect to the Demised Premises except as
expressly set forth in this Lease.

                                  ARTICLE 36
<PAGE>

                                 Rent Control

          In the event the minimum rent and/or additional rent or any part
thereof provided to be paid by Tenant under the provisions of this Lease during
the demised term shall become uncollectible or shall be reduced or required to
be reduced or refunded by virtue of any federal, state, county or city law,
order or regulation, or by any direction of a public officer or body pursuant to
law, or the orders, rules, code or regulations of any organization or entity
formed pursuant to law, Tenant shall enter into such agreement(s) and take such
other steps (without additional expense or liability to Tenant) as Landlord may
reasonably request and as may be legally permissible to permit Landlord to
collect the maximum rents which from time to time during the continuance of such
legal rent restriction may be legally permissible (and not in excess of the
amounts reserved therefor under this Lease). Upon the termination of such legal
rent restriction, (a) the minimum rent and/or additional rent shall become and
thereafter be payable in accordance with the amounts reserved herein for the
periods following such termination, and (b) Tenant shall pay to Landlord
promptly upon being billed, to the maximum extent legally permissible, an amount
equal to (i) minimum rent and/or additional rent which would have been paid
pursuant to this Lease but for such legal rent restriction less (ii) the rents
paid by Tenant during the period such legal rent restriction was in effect.

                                  ARTICLE 37

                            Landlord's Contribution

          Subject to the provisions of Article 5 of this Lease, and except for
the work to be performed by Landlord pursuant to Section 2.02, Tenant agrees to
perform the initial work and installations required to make the Demised Premises
suitable for the conduct of Tenant's business. Tenant agrees to deliver to
Landlord, for Landlord's approval the plans and specifications for Tenant's
initial work within sixty (60) days following the Commencement Date (the
"initial work"). Landlord agrees to contribute up to the sum of $1,912,500.00
("Landlord's Contribution") toward the cost of such work, which shall include
hard and soft costs. Landlord shall pay to Tenant, from time to time, but not
more often that once a month, ninety (90%) percent of the cost of the work
requested by Tenant theretofore performed by the contractor, provided Tenant
delivers to Landlord concurrently with its request, receipted bills of the
contractor involved approved by Tenant, a certificate by Tenant's architect that
such bills have been approved and the work or materials evidenced by such bills
have been satisfactorily performed or delivered and a waiver of mechanic's lien
signed by the contractor with respect to the amount paid as evidenced by the
receipted bill, such payment to be made to Tenant within ten (10) days after
receipt of Tenant's request together with the aforesaid documentation. Within
ten (10) days after Landlord receives a certificate from Tenant's architect
stating that Tenant's work has been substantially completed, that the same has
been performed in compliance with all applicable Governmental Requirements and
the approved plans and specifications and delivery to Landlord, if applicable,
of the final "sign-off" letters and equipment use permits (as necessary) for all
work performed from the applicable municipal authorities, Landlord shall pay to
Tenant the aggregate of the ten (10%) percent sums retained
<PAGE>

by Landlord. Landlord shall have no obligation or responsibility to pay any cost
exceeding the amount of Landlord's Contribution. If the amount Tenant expends
for the cost exceeds the amount of Landlord's Contribution, Tenant shall be
responsible for the payment to the contractors of the excess. If said amount is
less than the amount of Landlord's Contribution, Landlord shall apply such
difference to the payment of minimum rent as and when the same would otherwise
become due and payable under this Lease. Tenant shall indemnify and hold
Landlord harmless from and against any and all claims, costs and expenses in
connection with such work exceeding the amount of Landlord's Contribution.

                                  ARTICLE 38

                                Roof Equipment

          Tenant shall have the right to use its prorata share of the available
area on the roof designated by Landlord for the purpose of locating and/or
installing, at its own cost and expense, a satellite dish, antenna and/or
telecommunications equipment (collectively "Equipment"). However, if Landlord
thereafter is required to use additional area on the roof in connection with the
operation of the Building, and no other area on the roof is then available for
such purpose, Tenant's prorata share thereof shall be reduced accordingly and
Tenant shall remove its Equipment from such area and repair any damage caused
thereby. Tenant shall also have the right, subject to the provisions of Article
5, to install in the Building core area, risers, ducts, conduits or other
facilities, necessary to connect such Equipment to the Demised Premises or the
Additional Space (as hereinafter defined) then leased by Tenant. All such
Equipment and connecting facilities shall be installed and maintained in a
manner not to disturb the other tenants in the Building, the operation of the
Building systems therein, in compliance with all applicable Governmental
Requirements, and subject to plans showing the type of Equipment and connecting
facilities to be installed and its location and manner of installation, such
plans to be approved by Landlord. Tenant shall cause the Equipment to be covered
under Tenant's liability insurance policy. Tenant shall indemnify and hold
Landlord harmless from and against any loss, claim, damage or expense in
connection with or relating to the installation, maintenance and operation of
such Equipment and connecting facilities. Tenant, at its own cost, shall repair
any damage to the Building, roof and/or Demised Premises caused by such work,
and shall at all times maintain and repair the Equipment and wiring, including
any required replacements thereof.
<PAGE>

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

                                622 BUILDING COMPANY LLC,
                                By:  622 Building Corp.,
                                     its managing member

                                By:  /s/ Charles Steven Cohen
                                     -------------------------------------------
                                     Charles Steven Cohen, President

                                                                    Landlord

                                CMGI, INC.

                                By:  /s/ Andrew J. Hajducky III
                                     -------------------------------------------
                                     Andrew J. Hajducky III
                                     Executive Vice President, CFO and Treasurer

                                                                    Tenant<PAGE>

                                                                   EXHIBIT 10.40

                                     LEASE

                          TST 555/575 MARKET, L.L.C.,

                     a Delaware limited liability company,

                                   Landlord

                                      and

                                  CMGI, Inc.,

                            a Delaware corporation,

                                    Tenant

                                      for

                               575 Market Street

                           San Francisco, California

                               February 4, 2000
<PAGE>

                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                            Page
<S>                                                                         <C>
ARTICLE 1  BASIC LEASE PROVISIONS..........................................    1
ARTICLE 2  PREMISES, TERM, RENT............................................    3
ARTICLE 3  USE AND OCCUPANCY...............................................    4
ARTICLE 4  CONDITION OF THE PREMISES.......................................    5
ARTICLE 5  ALTERATIONS.....................................................    5
ARTICLE 6  REPAIRS.........................................................    7
ARTICLE 7  INCREASES IN TAXES AND OPERATING EXPENSES.......................    8
ARTICLE 8  REQUIREMENTS OF LAW.............................................   12
ARTICLE 9  SUBORDINATION...................................................   13
ARTICLE 10 SERVICES........................................................   15
ARTICLE 11 INSURANCE; PROPERTY LOSS OR DAMAGE..............................   16
ARTICLE 12 EMINENT DOMAIN..................................................   20
ARTICLE 13 ASSIGNMENT AND SUBLETTING.......................................   21
ARTICLE 14 ELECTRICITY.....................................................   26
ARTICLE 15 ACCESS TO PREMISES..............................................   27
ARTICLE 16 DEFAULT.........................................................   28
ARTICLE 17 LANDLORD'S RIGHT TO CURE; FEES AND EXPENSES.....................   31
ARTICLE 18 NO REPRESENTATIONS BY LANDLORD; LANDLORD'S APPROVAL.............   31
ARTICLE 19 END OF TERM.....................................................   32
ARTICLE 20 QUIET ENJOYMENT.................................................   32
ARTICLE 21 NO SURRENDER; NO WAIVER.........................................   33
ARTICLE 22 WAIVER OF TRIAL BY JURY, COUNTERCLAIM...........................   33
ARTICLE 23 NOTICES.........................................................   33
ARTICLE 24 RULES AND REGULATIONS...........................................   34
ARTICLE 25 BROKER..........................................................   34
ARTICLE 26 INDEMNITY.......................................................   34
ARTICLE 27 MISCELLANEOUS...................................................   35
ARTICLE 28 SECURITY DEPOSIT................................................   39
ARTICLE 29 PARKING.........................................................   40
</TABLE>
<PAGE>

                              Schedule of Exhibits
                              --------------------

Exhibit A-1    Floor Plan of the 12th Floor

Exhibit A-2    Floor Plan of the 13th Floor

Exhibit B      Definitions

Exhibit C      Workletter

Exhibit D      Design Standards

Exhibit E      Cleaning Specifications

Exhibit F      Rules and Regulations

Exhibit G      Form of Subordination, Non-Disturbance and Attornment Agreement
<PAGE>

                                     LEASE

          THIS LEASE is made as of the 4th day of February, 2000 ("Effective
Date"), between TST 555/575 MARKET, L.L.C. ("Landlord"), a Delaware limited
liability company, and CMGI, Inc. ("Tenant"), a Delaware corporation.

          Landlord and Tenant hereby agree as follows:

                                   ARTICLE 1

                            BASIC LEASE PROVISIONS

PREMISES                        The 12/th/ and 13/th/ floors of the Building, as
                                more particularly described on Exhibit A-1 and
                                A-2 attached hereto.

BUILDING                        The building, fixtures, equipment and other
                                improvements and appurtenances now located or
                                hereafter erected, located or placed upon the
                                land known as 575 Market Street, San Francisco,
                                California.

REAL PROPERTY                   The Building, together with the plot of land
                                upon which it stands.

SCHEDULED COMMENCEMENT DATE     February 1, 2000.

COMMENCEMENT DATE               The later to occur of (a) the Scheduled
                                Commencement Date, and (b) the Effective Date.

RENT COMMENCEMENT DATE          The earlier to occur of (a) the 60/th/calendar
                                day following the Commencement Date; and (b) the
                                date Tenant physically occupies the Premises for
                                purposes of commencing the conducting of its
                                business operations therein.

EXPIRATION DATE                 The day preceding the 7/th/ anniversary of the
                                Commencement Date.

TERM                            The period commencing on the Commencement Date
                                and ending on the Expiration Date.

PERMITTED USES                  Executive and general offices, including
                                computer data and laboratory rooms and studio
                                recording rooms, for the transaction of Tenant's
                                business in keeping with Comparable Buildings.

BASE YEAR                       Calendar year 2000.

TENANT'S PROPORTIONATE SHARE    5.095%.

AGREED AREA OF BUILDING         458,136 rentable square feet.

AGREED AREA OF PREMISES         12/th/ Floor: 11,671 rentable square feet
                                13/th/ Floor: 11,671 rentable square feet
                                Premises:     23,342 rentable square feet
<PAGE>

FIXED RENT                      Period         Per Annum        Per Month
                                ------         ---------        ----------
                                Months 1-42    $1,120,416.00    $93,368.00
                                Months 43-84   $1,190,442.00    $99,203.50

ADDITIONAL RENT                 All sums other than Fixed Rent payable by Tenant
                                to Landlord under this Lease, including Tenant's
                                Tax Payment, Tenant's Operating Payment, late
                                charges, overtime or excess service charges,
                                damages, and interest and other costs related to
                                Tenant's failure to perform any of its
                                obligations under this Lease.

RENT                            Fixed Rent and Additional Rent, collectively.

ADVANCE RENT                    $93,368.00 (which shall be applied toward Fixed
                                Rent for the first month of the Term)

INTEREST RATE                   The lesser of (i) 4% per annum above the then-
                                current Base Rate, or (ii) the maximum rate
                                permitted by applicable law.

SECURITY DEPOSIT                $93,368.00.

TENANT'S ADDRESS FOR NOTICES    CMGI, Inc.
                                100 Brickstone Square
                                Andover, Massachusetts  01810
                                Attn: General Counsel

                                Copies to:

                                Hale and Dorr LLP
                                60 State Street
                                Boston, Massachusetts  02109
                                Attn:  Pamela Coravos, Esq.

LANDLORD'S ADDRESS FOR NOTICES  TST 555/575, L.L.C.
                                c/o Tishman Speyer Properties, L.P.
                                520 Madison Avenue, Sixth Floor
                                New York, New York  10022
                                Attn:  Chief Financial Officer
                                Copies to:

                                TST 555/575 Market, L.L.C.
                                c/o Tishman Speyer Properties, L.P.
                                575 Market Street, 20th Floor
                                San Francisco, California  94105
                                Attn: Property Manager

                                and:

                                Tishman Speyer Properties, L.P.
                                520 Madison Avenue, Sixth Floor
                                New York, New York  10022
                                Attn:  General Counsel

                                       2
<PAGE>

TENANT'S BROKER                 Cushman Realty Corporation and CRF Partners,
                                Inc.

LANDLORD'S AGENT                Tishman Speyer Properties, L.P. or any other
                                person designated at any time and from time to
                                time by Landlord as Landlord's Agent and their
                                successors and assigns.

LANDLORD'S CONTRIBUTION         $466,840.00 ($20.00 per rentable square foot).

PARKING PRIVILEGES              2.

All capitalized terms used in this Lease without definition are defined in
Exhibit B.

                                   ARTICLE 2

                             PREMISES, TERM, RENT

     Section 2.1    Lease of Premises. Subject to the terms of this Lease,
Landlord leases to Tenant and Tenant leases from Landlord the Premises for the
Term. In addition, Landlord grants to Tenant the right to use, on a non-
exclusive basis and in common with other tenants, the Common Areas.

     Section 2.2    Commencement Date. Upon the Effective Date, the terms and
provisions hereof shall be fully binding on Landlord and Tenant prior to the
occurrence of the Commencement Date. The Term of this Lease shall commence on
the Commencement Date. Unless sooner terminated or extended as hereinafter
provided, the Term shall end on the "Expiration Date" specified in Article 1. If
Landlord does not tender possession of the Premises to Tenant on or before the
Scheduled Commencement Date, for any reason whatsoever, Landlord shall not be
liable for any damage thereby, and this Lease shall not be void or voidable
thereby. No failure to tender possession of the applicable portion of the
Premises to Tenant on or before the Scheduled Commencement Date shall in any way
affect any other obligations of Tenant hereunder. Once the Rent Commencement
Date is determined, Landlord and Tenant shall execute an agreement stating the
Commencement Date, Rent Commencement Date and Expiration Date, but the failure
to do so will not affect the determination of such dates. For purposes of
determining whether Tenant has accepted possession of the Premises, Tenant shall
be deemed to have done so when Tenant first moves Tenant's Property and/or any
of its personnel into the Premises, except to the extent that Tenant is
authorized in this Lease or by Landlord's agreement to do any of the foregoing
without being deemed to have accepted possession of the Premises.

     Section 2.3    Payment of Rent. Tenant shall pay to Landlord, without
notice or demand, and without any set-off, counterclaim, abatement or deduction
whatsoever, except as may be expressly set forth in this Lease, in lawful money
of the United States by wire transfer of funds or by check drawn upon a bank
approved by Landlord, (i) Fixed Rent in equal monthly installments, in advance,
on the first day of each calendar month during the Term, commencing on the Rent
Commencement Date, and (ii) Additional Rent, at the times and in the manner set
forth in this Lease.

     Section 2.4    First Month's Rent. Tenant shall pay the Advance Rent upon
the execution of this Lease. If the Rent Commencement Date is on the first day
of a month, the Advance Rent shall be credited towards the first month's Fixed
Rent payment. If the Rent Commencement Date is not the first day of a month,
then on the Rent Commencement Date, Tenant shall pay Fixed Rent for the period
from the Rent Commencement Date through the last day of such month, and the
Advance Rent shall be credited towards Fixed Rent for the next succeeding
calendar month.

     Section 2.5    Early Access. Provided that no Tenant Parties unreasonably
interfere with Landlord's work in the Premises, Landlord shall allow Tenant
access to the Premises to install

                                       3
<PAGE>

cabling, furniture and equipment which shall not be deemed acceptance of
possession for purposes of Section 2.2. Before Tenant's entry into the Premises
as permitted hereunder, Tenant shall submit a schedule to Landlord (and
Landlord's contractor, if so requested by Landlord), for their reasonable
approval, which schedule shall detail the timing and purpose of Tenant's entry.
Tenant shall hold Landlord harmless from and indemnify and protect and defend
Landlord against any loss or damage to the Premises and against injury to any
person caused by Tenant's actions as a result of such entry.

     Section 2.6    Termination Right. Subject to the following terms and
provisions, Tenant shall have a one time option, exercisable by not less than 12
months' prior written notice to Landlord (the "Termination Notice") (which
Termination Notice shall be irrevocable) to terminate this Lease effective as of
the last day of the 60th month following the Commencement Date. If Tenant elects
to so terminate this Lease, Tenant shall pay to Landlord, concurrently with
Tenant's delivery of the Termination Notice, a termination fee (the "Termination
Fee") in an amount equal to $515,977. If Tenant fails to timely deliver the
Termination Notice and include therewith the Termination Fee, then Tenant's
rights pursuant to this Section 2.6 shall lapse and be of no further force or
effect. Tenant's payment of the Termination Fee shall not relieve Tenant of its
obligation to timely pay rent for the balance of the Term.

     Section 2.7    Interim Occupancy. For a period commencing on the
Commencement Date and ending on the Rent Commencement Date (the "Interim
Occupancy Period"), Tenant shall be permitted to use and occupy the 11th floor
of the Building (the "Interim Premises"); provided that if due to Unavoidable
Delays (excluding in all cases any delays caused by the acts, failure to act or
omissions of Tenant) the Initial Installations are not Substantially Complete by
the Rent Commencement Date, then the Interim Occupancy Date shall be extended by
the amount of such Unavoidable Delay but in no event more than an additional
period of 30 days. Tenant acknowledges that, (a) Landlord has made no
representations concerning the physical condition of the Interim Premises or the
suitability thereof for Tenant's intended use; (b) Landlord has no obligation to
perform any improvements, alterations, refurbishments or repairs in order to
ready the Interim Premises for Tenant's use; (c) Tenant shall accept Landlord's
tender of possession of the Interim Premises in their then "As-Is" condition;
and (d) during the Interim Occupancy Period, Tenant may not perform any
Alterations to the Interim Premises, other than the installation of telephone
and data cabling. Tenant's occupancy of the Interim Premises shall be upon all
of the terms and provisions of this Lease, except that the Fixed Rent payable
for the Interim Premises shall be $34,040 per month, prorated for any partial
periods based upon the actual number of days in the subject calendar month. If
Tenant fails to vacate the Interim Premises on the last day of the Interim
Occupancy Period (in broom-clean condition), Tenant shall be deemed in holdover
of the Interim Premises, which holdover shall be subject to Section 19.2 of this
Lease.

                                   ARTICLE 3

                               USE AND OCCUPANCY

          Tenant shall use and occupy the Premises for the Permitted Uses and
for no other purpose.  Tenant shall not use or occupy or permit the use or
occupancy of any part of the Premises in a manner constituting a Prohibited Use.
If Tenant uses the Premises for a purpose constituting a Prohibited Use,
violating any Requirement, or causing the Building to be in violation of any
Requirement, then Tenant shall promptly discontinue such use upon notice of such
violation.  Tenant, at its expense, shall procure and at all times maintain and
comply with the terms and conditions of all licenses and permits required for
the lawful conduct of the Permitted Uses in the Premises.  If Tenant installs a
recording studio within the Premises, such recording studio shall be
soundproofed in a manner reasonably acceptable to Landlord to prevent the
transmission of noise or vibrations to the premises of other tenants of the
Building.  Landlord and Tenant agree that the recording studio improvements
constitute Specialty Alterations.

                                       4
<PAGE>

                                   ARTICLE 4

                           CONDITION OF THE PREMISES

          Tenant has inspected the Premises and agrees (a) to accept possession
of each portion of the Premises in the condition existing on the respective Rent
Commencement Date "as is", but subject to Landlord's obligation to maintain the
Premises as expressly provided herein, (b) that neither Landlord nor Landlord's
agents have made any representations or warranties with respect to the Premises
or the Building except as expressly set forth herein, and (c) except for
Landlord's Contribution described in  Exhibit "C" attached hereto, Landlord has
no obligation to perform any work, supply any materials, incur any expense or
make any alterations or improvements to prepare the Premises for Tenant's
occupancy.  Tenant's occupancy of any part of the Premises shall be conclusive
evidence, as against Tenant, that Tenant has accepted possession of the Premises
in its then current condition and at the time such possession was taken, the
Premises and the Building were in a good and satisfactory condition as required
by this Lease.  Tenant agrees and acknowledges that it shall be responsible, at
its sole cost and expense, for (i) ensuring that the core hardware to be
installed on all doors within the Premises by Tenant shall be Building Standard
lever-type where required by the Americans With Disabilities Act of 1990 (the
"ADA"), (ii) bringing the toilet rooms within the Premises into compliance with
the ADA, (iii) upgrading the lobby separation doors on each floor in accordance
with applicable Requirements; and (iv) replacing ceiling tiles in accordance
with Building Standards as reasonably established by Landlord.

                                   ARTICLE 5

                                  ALTERATIONS

     Section 5.1    Tenant's Alterations. (a) Tenant shall not make any
alterations, additions or other physical changes in or about the Premises
(collectively, "Alterations") other than decorative Alterations such as
painting, wall coverings and floor coverings (collectively, "Decorative
Alterations"), without Landlord's prior consent, which consent shall not be
unreasonably withheld or delayed so long as such Alterations (i) are non-
structural and do not affect any Building Systems, (ii) affect only the Premises
and are not visible from outside of the Premises, (iii) do not affect the
certificate of occupancy issued for the Building or the Premises, and (iv) do
not violate any Requirement.

          (b)  Plans and Specifications. Prior to making any Alterations,
Tenant, at its expense, shall (i) submit to Landlord for its written approval,
detailed plans and specifications ("Plans") of each proposed Alteration (other
than Decorative Alterations), and with respect to any Alteration affecting any
Building System, evidence that the Alteration has been designed by, or reviewed
and approved by, Landlord's designated engineer for the affected Building
System, (ii) obtain all permits, approvals and certificates required by any
Governmental Authorities, (iii) furnish to Landlord duplicate original policies
or certificates of worker's compensation (covering all persons to be employed by
Tenant, and Tenant's contractors and subcontractors in connection with such
Alteration) and commercial general liability (including property damage
coverage) insurance and Builder's Risk coverage (as described in Article 11) all
in such form, with such companies, for such periods and in such amounts as
Landlord may reasonably require, naming Landlord, Landlord's Agent any Lessor
and any Mortgagee as additional insureds, and (iv) furnish to Landlord
reasonably satisfactory evidence of Tenant's ability to complete and to fully
pay for such Alterations (other than Decorative Alterations). Tenant shall give
Landlord not less than 5 Business Days' notice prior to performing any
Decorative Alteration, which notice shall contain a description of such
Decorative Alteration.

          (c)  Governmental Approvals. Tenant, at its expense, shall, as and
when required, promptly obtain certificates of partial and final approval of
such Alterations required by any Governmental Authority and shall furnish
Landlord with copies thereof, together with "as-built" Plans for such
Alterations prepared on an AutoCAD Computer Assisted Drafting and Design System
(or

                                       5
<PAGE>

such other system or medium as Landlord may accept), using naming conventions
issued by the American Institute of Architects in June, 1990 (or such other
naming conventions as Landlord may accept) and magnetic computer media of such
record drawings and specifications translated in DFX format or another format
acceptable to Landlord.

     Section 5.2    Manner and Quality of Alterations. All Alterations shall be
performed (a) in a good and workmanlike manner and materially free from defects,
(b) substantially in accordance with the Plans, and by contractors approved by
Landlord, and (c) in compliance with all Requirements, the terms of this Lease
and all construction procedures and regulations then prescribed by Landlord. All
materials and equipment shall be of first quality and at least equal to the
applicable standards for the Building then established by Landlord, and no such
materials or equipment (other than Tenant's Property) shall be subject to any
lien or other encumbrance.

     Section 5.3    Removal of Tenant's Property. Tenant's Property shall remain
the property of Tenant and Tenant may remove the same at any time on or before
the Expiration Date. On or prior to the Expiration Date, Tenant shall, unless
otherwise directed by Landlord, at Tenant's expense, remove any Specialty
Alteration designated in writing by Landlord to be removed at the time consent
thereto was granted and close up any slab penetrations in the Premises. Tenant
shall repair and restore, in a good and workmanlike manner, any damage to the
Premises or the Building caused by Tenant's removal of any Specialty Alterations
or Tenant's Property or by the closing of any slab penetrations, and upon
default thereof, Tenant shall reimburse Landlord, within 30 days of delivery of
an invoice therefor, for Landlord's cost of repairing and restoring such damage.
Any Above Building Standard Installations (as hereinafter defined) or Tenant's
Property not so removed shall be deemed abandoned and Landlord may remove and
dispose of same, and repair and restore any damage caused thereby, at Tenant's
cost and without accountability to Tenant. Tenant shall not be required to
remove any of the Improvements or any subsequent Alterations unless, in either
case, the same constitute Specialty Alterations which Landlord advises Tenant in
writing must be removed at the time consent thereto was granted. If requested by
Tenant prior to the installation of any component of the Improvements or of any
Alterations, Landlord will notify Tenant in writing whether (i) any such
component of the Improvements or any such Alterations, or any material component
thereof (including, without limitation, any oversized or exposed conduit) not
expressly included within the definition of Specialty Alterations is considered
by Landlord to be such and (ii) Landlord will waive any requirement that Tenant
remove the same upon the expiration or earlier termination of this Lease.

     Section 5.4    Mechanic's Liens. Tenant, at its expense, shall discharge
any lien or charge filed against the Real Property in connection with any work
done or claimed to have been done by or on behalf of, or materials furnished or
claimed to have been furnished to, Tenant, within 10 days after Tenant's receipt
of notice thereof by payment, filing the bond required by law or otherwise in
accordance with law.

     Section 5.5    Labor Relations. Tenant shall not employ, or permit the
employment of, any contractor, mechanic or laborer, or permit any materials to
be delivered to or used in the Building, if, in Landlord's reasonable judgment,
such employment, delivery or use will interfere or cause any conflict with other
contractors, mechanics or laborers engaged in the construction, maintenance or
operation of the Building by Landlord, Tenant or others. If such interference or
conflict occurs, upon Landlord's request, Tenant shall cause all contractors,
mechanics or laborers causing such interference or conflict to leave the
Building immediately.

     Section 5.6    Tenant's Costs. Tenant shall pay to Landlord, within 30 days
of demand therefor, all out-of-pocket costs actually incurred by Landlord in
connection with Tenant's Alterations, including costs incurred in connection
with (a) Landlord's review of the Alterations (including review of requests for
approval thereof) and (b) the provision of Building personnel during the
performance of any Alteration, to operate elevators or otherwise to facilitate
Tenant's Alterations. In addition, if Tenant's Alterations (exclusive of
Decorative Alterations and the installation of furniture, fixtures and
equipment, data wiring and computer equipment) cost more than $25,000.00, Tenant
shall pay to

                                       6
<PAGE>

Landlord, within 30 days of demand therefor, an administrative fee in an amount
equal to 5% of the total cost of such Alterations.

     Section 5.7    Tenant's Equipment. Tenant shall provide notice to Landlord
prior to moving any heavy machinery, heavy equipment, freight, bulky matter or
fixtures (collectively, "Equipment") into or out of the Building and shall pay
to Landlord any costs actually incurred by Landlord in connection therewith. If
such Equipment requires special handling, Tenant agrees (a) to employ only
persons holding all necessary licenses to perform such work, (b) all work
performed in connection therewith shall comply with all applicable Requirements
and (c) such work shall be done only during hours designated by Landlord.

     Section 5.8    Legal Compliance. The approval of Plans, or consent by
Landlord to the making of any Alterations, does not constitute Landlord's
representation that such Plans or Alterations comply with any Requirements.
Landlord shall not be liable to Tenant or any other party in connection with
Landlord's approval of any Plans, or Landlord's consent to Tenant's performing
any Alterations. If any Alterations made by or on behalf of Tenant, require
Landlord to make any alterations or improvements to any part of the Building in
order to comply with any Requirements, Tenant shall pay all costs and expenses
incurred by Landlord in connection with such alterations or improvements.

     Section 5.9    Floor Load. Tenant shall not place a load upon any floor of
the Premises that exceeds 50 pounds per square foot "live load". Landlord
reserves the right to reasonably designate the position of all Equipment which
Tenant wishes to place within the Premises, and to place limitations on the
weight thereof.

                                   ARTICLE 6

                                    REPAIRS

     Section 6.1    Landlord's Repair and Maintenance. Landlord shall operate,
maintain and, except as provided in Section 6.2 hereof, make all necessary
repairs (both structural and nonstructural) to (i) the Building Systems, (ii)
the Common Areas and (iii) the toilet rooms located within the Premises (other
than any executive restrooms installed by Tenant), in conformance with standards
applicable to Comparable Buildings and in compliance with all Requirements.

     Section 6.2    Tenant's Repair and Maintenance. Tenant shall promptly, at
its expense and in compliance with Article 5, make all nonstructural repairs to
the Premises (including the toilet rooms and elevator lobbies) and the fixtures,
equipment and/or and appurtenances therein other than the Building Systems
(collectively, "Building Fixtures") as and when needed to preserve the Premises
in good working order and condition, except for reasonable wear and tear and
damage for which Tenant is not responsible. All damage to the Building or to any
portion thereof, or to any Building Fixtures requiring structural or
nonstructural repair caused by or resulting from the negligence or willful
misconduct or improper conduct of or the moving of Tenant's Property or
Equipment into, within or out of the Premises by a Tenant Party, shall be
repaired at Tenant's expense by (i) Tenant, if the required repairs are
nonstructural in nature and do not affect any Building System, or (ii) Landlord,
if the required repairs are structural in nature, involve replacement of
exterior window glass or affect any Building System. All Tenant repairs shall be
of good quality utilizing new construction materials. If Tenant fails after 10
days' notice (or such shorter period as may be required in an emergency) to
proceed with due diligence to make any repairs required to be made by Tenant,
Landlord may make such repairs and all costs and expenses incurred by Landlord
on account thereof, plus interest thereon at the Interest Rate, shall be paid by
Tenant within 10 days after delivery of an invoice therefor.

     Section 6.3    Interruptions Due to Repairs. Landlord reserves the right to
make all changes, alterations, additions, improvements, repairs or replacements
to the Building, including the Building Systems (collectively, "Restorative
Work"), as Landlord deems necessary or desirable, provided that in no event
shall the level of any Building service decrease in any material respect from

                                       7
<PAGE>

the level required of Landlord in this Lease as a result thereof (other than
temporary changes in the level of such services during the performance of any
such Restorative Work). Landlord shall use reasonable efforts to minimize
interference with Tenant's use and occupancy of the Premises during the
performance of such Restorative Work. There shall be no Rent abatement or
allowance to Tenant for a diminution of rental value, no actual or constructive
eviction of Tenant, in whole or in part, no relief from any of Tenant's other
obligations under this Lease, and no liability on the part of Landlord by reason
of inconvenience, annoyance or injury to business arising from Landlord, Tenant
or others performing, or failing to perform, any Restorative Work.
Notwithstanding any contrary provision of this Lease, if Tenant is prevented
from using for the conduct of its business, and does not use for the conduct of
its business, the Premises or any material portion thereof, for fifteen (15)
consecutive Business Days (the "Eligibility Period") as a result of (i) any
construction, repair, maintenance or alteration performed by Landlord after the
Commencement Date and not necessitated by the negligence or willful misconduct
of any Tenant Party, or (ii) the failure in any material respect of Landlord or
its agents or contractors to provide to the Premises any of the utilities and
services required to be provided under this Lease (including Articles 10 and 14
below) and not caused by the negligence or willful misconduct of any Tenant
Party or otherwise due to the occurrence of a casualty or condemnation, or (iii)
any failure to provide access to the Premises and not caused by the negligence
or willful misconduct of any Tenant Party or otherwise due to the occurrence of
a casualty or condemnation, then, in any and all such events, Tenant's
obligation to pay Fixed Rent, Tenant's Operating Payment and Tenant's Tax
Payment shall be abated or reduced, as the case may be, from and after the first
(1st) day following the last day of the Eligibility Period and continuing for
such time that Tenant continues to be so prevented from using for the conduct of
its business, and does not so use for the conduct of its business, the Premises
or a material portion thereof, in the proportion that the rentable square feet
of the portion of the Premises that Tenant is prevented from using, and does not
so use, bears to the total rentable square feet of the Premises.

                                   ARTICLE 7

                   INCREASES IN TAXES AND OPERATING EXPENSES

     Section 7.1    Definitions. For the purposes of this Article 7, the
following terms shall have the meanings set forth below:

          (a)  "Assessed Valuation" shall mean the amount for which the Real
Property is assessed by the County Assessor of the City and County of San
Francisco for the purpose of imposition of Taxes.

          (b)  "Base Operating Expenses" shall mean the Operating Expenses for
the Base Year.

          (c)  "Base Taxes" shall mean the Taxes payable on account of the Base
Year.

          (d)  "Comparison Year" shall mean any calendar year commencing
subsequent to the Base Year.

          (e)  "Operating Expenses" shall mean the aggregate of all costs and
expenses paid or incurred by or on behalf of Landlord in connection with the
ownership, operation, repair and maintenance of the Real Property, including
capital improvements only if such capital improvement either (i) is reasonably
intended to result in a reduction in Operating Expenses (as for example, a
labor-saving improvement) provided, the amount included in Operating Expenses in
any Comparison Year shall not exceed an amount equal to the savings reasonably
anticipated to result from the installation and operation of such improvement,
and/or (ii) is made during any Comparison Year in compliance with Requirements
enacted or imposed after the Effective Date (including the interpretation,
amendment or modification after the Effective Date of Requirements enacted or
imposed prior to the Effective Date). Such capital improvements shall be
amortized (with interest at the Base Rate) on a straight-line basis over such
period as Landlord shall reasonably determine, and

                                       8
<PAGE>

the amount included in Operating Expenses in any Comparison Year shall be equal
to the annual amortized amount. Operating Expenses shall not include any
Excluded Expenses. If during all or part of the Base Year or any Comparison
Year, Landlord shall not furnish any particular item(s) of work or service
(which would otherwise constitute an Operating Expense) to any leasable portions
of the Building for any reason, then, for purposes of computing Operating
Expenses for such period, the amount included in Operating Expenses for such
period shall be increased by an amount equal to the costs and expenses that
would have been reasonably incurred by Landlord during such period if Landlord
had furnished such item(s) of work or service to such portion of the Building.
In determining the amount of Operating Expenses for the Base Year or any
Comparison Year, if less than 95% of the Building rentable area is occupied by
tenants at any time during any such Base Year or Comparison Year, Operating
Expenses shall be determined for such Base Year or Comparison Year to be an
amount equal to the like expenses which would normally be expected to be
incurred had such occupancy been 95% throughout such Base Year or Comparison
Year. Tenant understands and acknowledges that, from time to time during the
Term, the Building may be operated by Landlord as part of a larger office
complex, comprising the Building, the Plaza and Common Areas adjacent to the
Building and that certain other office building commonly known as 555 Market
Street ("555 Market"). For purposes of this Article 7, the Building and 555
Market are sometimes hereinafter jointly referred to as the "Project." Landlord
shall have the right, from time to time during the Term, to operate the Project
in an integrated fashion, and to include within Operating Expenses and Real
Property Taxes the amount of Operating Expenses and Real Property Taxes paid or
incurred by Landlord with respect to the Project. During such periods of time as
Landlord so elects, "Base Year Operating Expenses" and "Base Year Taxes" shall
be deemed to mean Operating Expenses and Real Estate Taxes incurred by Landlord
for the Project during the Base Year, and "Tenant's Percentage Share" shall mean
the product of (a) the Rentable Area of the Premises, and (b) a fraction, the
numerator of which is one and the denominator of which is the Rentable Area of
the Project. In addition, during such periods of time as Landlord does not elect
to determine Operating Expenses and Real Property Taxes on a Project-wide basis,
Operating Expenses and Real Estate Taxes for the Building shall include a
reasonable allocation of such costs and expenses as Landlord may incur in the
maintenance, operation, administration and repair of the Common Areas servicing
the Project.

          (f)  "Statement" shall mean a statement containing a comparison of (i)
the Taxes payable for the Base Year and for any Comparison Year, or (ii) the
Base Operating Expenses and the Operating Expenses payable for any Comparison
Year.

          (g)  "Taxes" shall mean (i) all real estate taxes, assessments, sewer
and water rents, rates and charges and other governmental levies, impositions or
charges, whether general, special, ordinary, extraordinary, foreseen or
unforeseen, which may be assessed, levied or imposed upon all or any part of the
Real Property, and (ii) all expenses (including reasonable attorneys' fees and
disbursements and experts' and other witnesses' fees) incurred in contesting any
of the foregoing or the Assessed Valuation of the Real Property; provided that
Landlord's determination to prosecute such contest is reasonable under the
prevailing circumstances as measured by the reasonably anticipated cost and
Landlord's determination of the reasonable scope of potential savings). Taxes
shall not include (x) interest or penalties incurred by Landlord as a result of
Landlord's late payment of Taxes, or (y) any franchise, net income, excess
profits, gift, capital stock, inheritance, succession or estate taxes imposed
upon Landlord. If Landlord elects to pay any assessment in annual installments,
then (i) such assessment shall be deemed to have been so divided and to be
payable in the maximum number of installments permitted by law, and (ii) there
shall be deemed included in Taxes for each Comparison Year the installments of
such assessment becoming payable during such Comparison Year, together with
interest payable during such Comparison Year on such installments and on all
installments thereafter becoming due as provided by law, all as if such
assessment had been so divided. If at any time the methods of taxation
prevailing on the Effective Date shall be altered so that in lieu of or as an
addition to the whole or any part of Taxes, there shall be assessed, levied or
imposed (1) a tax, assessment, levy, imposition or charge based on the income or
rents received from the Real Property whether or not wholly or partially as a
capital levy or otherwise, (2) a

                                       9
<PAGE>

tax, assessment, levy, imposition or charge measured by or based in whole or in
part upon all or any part of the Real Property and imposed upon Landlord, (3) a
license fee measured by the rents, or (4) any other tax, assessment, levy,
imposition, charge or license fee however described or imposed, then all such
taxes, assessments, levies, impositions, charges or license fees or the part
thereof so measured or based shall be deemed to be Taxes.

     Section 7.2    Tenant's Tax Payment. (a) If the Taxes payable for any
Comparison Year exceed the Base Taxes, Tenant shall pay to Landlord Tenant's
Proportionate Share of such excess ("Tenant's Tax Payment"). On or about the
start of each Comparison Year, Landlord shall furnish to Tenant a Statement of
the Taxes. Tenant shall pay Tenant's Tax Payment to Landlord, in monthly
installments, on the first day of each month during each Comparison Year, an
amount equal to 1/12 of Tenant's Tax Payment due for each Comparison Year. If
there is any increase or decrease in Taxes payable for any Comparison Year,
whether levied during or after such Comparison Year, Landlord may furnish a
revised Statement for such Comparison Year, Tenant's Tax Payment for such
Comparison Year shall be adjusted and, within 30 days after delivery of such
revised Statement (a) with respect to any increase in Taxes payable for such
Comparison Year, Tenant shall pay such increase in Tenant's Tax Payment to
Landlord, or (b) with respect to any decrease in Taxes payable for such
Comparison Year, Landlord shall credit such decrease in Tenant's Tax Payment
against the next installment of Rent payable by Tenant.

          (b)  Only Landlord may institute proceedings to reduce the Assessed
Valuation of the Real Property and the filings of any such proceeding by Tenant
without Landlord's consent shall constitute an Event of Default. If the Taxes
payable for the Base Year are reduced, the Base Taxes shall be correspondingly
revised, the Additional Rent previously paid or payable on account of Tenant's
Tax Payment hereunder for all Comparison Years shall be recomputed on the basis
of such reduction, and Tenant shall pay to Landlord within 30 days after being
billed therefor, any deficiency between the amount of such Additional Rent
previously computed and paid by Tenant to Landlord, and the amount due as a
result of such recomputations. If Landlord receives a refund of Taxes for any
Comparison Year, Landlord shall, at its election, either pay to Tenant, or
credit against subsequent payments of Rent due hereunder, an amount equal to
Tenant's Proportionate Share of the refund, net of any expenses incurred by
Landlord in achieving such refund and not otherwise included within Taxes, which
amount shall not exceed Tenant's Tax Payment paid for such Comparison Year.
Landlord shall not be obligated to file any application or institute any
proceeding seeking a reduction in Taxes or the Assessed Valuation.

          (c)  Tenant shall be responsible for any applicable occupancy or rent
tax now in effect or hereafter enacted and, if payable by Landlord, Tenant shall
pay such amounts to Landlord, within 30 days of Landlord's demand therefor.

     Section 7.3    Tenant's Operating Payment. (a) If the Operating Expenses
payable for any Comparison Year exceed the Base Operating Expenses, Tenant shall
pay to Landlord Tenant's Proportionate Share of such excess ("Tenant's Operating
Payment"). For each Comparison Year, Landlord shall furnish to Tenant a
statement setting forth Landlord's reasonable estimate of Tenant's Operating
Payment for such Comparison Year (the "Estimate"). Tenant shall pay to Landlord
on the 1/st/ day of each month during such Comparison Year an amount equal to
1/12 of Landlord's estimate of Tenant's Operating Payment for such Comparison
Year. If Landlord furnishes an Estimate for a Comparison Year subsequent to the
commencement thereof, then (a) until the 1/st/ day of the month following the
month in which the Estimate is furnished to Tenant, Tenant shall pay to Landlord
on the 1/st/ day of each month an amount equal to the monthly sum payable by
Tenant to Landlord under this Section 7.3 during the last month of the preceding
Comparison Year, (b) promptly after the Estimate is furnished to Tenant or
together therewith, Landlord shall give notice to Tenant stating whether the
installments of Tenant's Operating Payment previously made for such Comparison
Year were greater or less than the installments of Tenant's Operating Payment to
be made for such Comparison Year in accordance with the Estimate, and (i) if
there shall be a deficiency, Tenant shall pay the amount thereof within 10
Business Days after demand therefor, or (ii) if there shall have been an

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<PAGE>

overpayment, Landlord shall credit the amount thereof against subsequent
payments of Rent due hereunder, and (c) on the 1/st/ day of the month following
the month in which the Estimate is furnished to Tenant, and on the 1/st/ day of
each month thereafter throughout the remainder of such Comparison Year, Tenant
shall pay to Landlord an amount equal to 1/12 of Tenant's Operating Payment
shown on the Estimate.

          (b)  On or before May 1/st/ of each Comparison Year, Landlord shall
furnish to Tenant a Statement for the immediately preceding Comparison Year. If
the Statement shows that the sums paid by Tenant under Section 7.3(a) exceeded
the actual amount of Tenant's Operating Payment for such Comparison Year,
Landlord shall credit the amount of such excess against subsequent payments of
Rent due hereunder. If the Statement shows that the sums so paid by Tenant were
less than Tenant's Operating Payment for such Comparison Year, Tenant shall pay
the amount of such deficiency within 10 Business Days after delivery of the
Statement to Tenant.

     Section 7.4    Non-Waiver; Disputes. (a) Landlord's failure to render
any Statement on a timely basis with respect to any Comparison Year within 3
years of the end thereof shall not prejudice Landlord's right to thereafter
render a Statement with respect to such Comparison Year prior to the expiration
of such 3 year period or any subsequent Comparison Year, nor shall the rendering
of a Statement prejudice Landlord's right to thereafter render a corrected
Statement for that Comparison Year within 3 years of the end thereof.

          (b)  Each Statement sent to Tenant shall be conclusively binding upon
Tenant unless Tenant (i) pays to Landlord when due the amount set forth in such
Statement, without prejudice to Tenant's right to dispute such Statement, and
(ii) within 90 days after such Statement is sent, sends a notice to Landlord
objecting to such Statement and specifying the reasons therefor.  Tenant agrees
that Tenant will not employ, in connection with any dispute under this Lease,
any person who is to be compensated in whole or in part, on a contingency fee
basis.  If the parties are unable to resolve any dispute as to the correctness
of such Statement within 30 days following such notice of objection, either
party may refer the issues raised to one of the "Big Five" public accounting
firms selected by Landlord and reasonably acceptable to Tenant, and the decision
of such accountants shall be conclusively binding upon Landlord and Tenant.  In
connection therewith, Tenant and such accountants shall execute and deliver to
Landlord a confidentiality agreement, in form and substance reasonably
satisfactory to Landlord, whereby such parties agree not to disclose to any
third party any of the information obtained in connection with such review.
Tenant shall pay the fees and expenses relating to such procedure, unless such
accountants determine that Landlord overstated Operating Expenses by more than
5% for such Comparison Year, in which case Landlord shall pay such fees and
expenses.

     Section 7.5    Final Year of Term. If the Expiration Date occurs on a date
other than December 31st, any Additional Rent under this Article 7 for the
Comparison Year in which such Expiration Date occurs shall be apportioned on the
basis of the number of days in the period from January 1/st/ to the Expiration
Date. Upon the expiration or earlier termination of this Lease, any Additional
Rent under this Article 7 shall be paid or adjusted within 30 days after
submission of the Statement.

     Section 7.6    No Reduction in Rent. In no event shall any decrease in
Operating Expenses or Taxes in any Comparison Year below the Base Operating
Expenses or Base Taxes, as the case may be, result in a reduction in the Fixed
Rent or any other component of Additional Rent payable hereunder.

     Section 7.7    Computation of Operating Expenses. Operating Expenses shall
be computed in accordance with the following general principles:

          (a)  Recovery Limited to Actual Costs. In no event shall Tenant pay
more during any calendar year than one hundred percent (100%) of Tenant's
Proportionate Share of the actual increase in Operating Expenses incurred by
Landlord during such calendar year, as adjusted pursuant to Section 7.1(e), and
Landlord shall not recover the cost of any items more than once;

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<PAGE>

          (b)  Arm's Length. All services rendered to and materials supplied to
the Building shall be rendered or supplied at a cost comparable to those charged
in arm's-length transactions for similar services or materials rendered or
supplied for similar purposes to Comparable Buildings;

          (c)  Accounting Policies. The accrual basis of accounting used in
determining Base Year Direct Expenses shall be consistently applied in
determining Operating Expenses in subsequent calendar years; and

          (d)  Assessments. All assessments and premiums which are not
specifically charged to Tenant because of what Tenant has done, which can be
paid by Landlord in installments, shall be paid by Landlord in the maximum
number of installments permitted by law and not included in Operating Expenses
except in the year in which the assessment or premium installment is due
actually paid; provided, however, that if the prevailing practice in other
Comparable Buildings is to pay such assessments or premiums on an earlier basis,
and Landlord pays on such basis, such assessments or premiums shall be included
in Operating Expenses as paid by Landlord; in no event, however, shall Landlord
include any accrued interest (resulting from such assessments or premiums) in
its computation of Operating Expenses.

                                   ARTICLE 8

                              REQUIREMENTS OF LAW

     Section 8.1    Compliance with Requirements.

          (a)  Tenant's Compliance.  Tenant, at its expense, shall comply with
all Requirements applicable to the Premises; provided, however, that Tenant
shall not be obligated to comply with any Requirements requiring any structural
alterations to the Building or alterations to the Building Systems or to the
Common Areas unless the application of such Requirements arises from (i) the
specific manner and nature of Tenant's use or occupancy of the Premises, as
distinct from general office use, (ii) Alterations made by Tenant, or (iii) a
breach by Tenant of any provisions of this Lease. Any such repairs or
alterations shall be made at Tenant's expense by Tenant (1) in compliance with
Article 5 if such repairs or alterations are nonstructural and do not affect any
Building System, or (2) by Landlord if such repairs or alterations are
structural or affect any Building System. If Tenant obtains knowledge of any
failure to comply with any Requirements applicable to the Premises, Tenant shall
give Landlord prompt written notice thereof.

          (b)  Hazardous Materials. Tenant shall not cause or permit (i) any
Hazardous Materials to be brought into the Building, (ii) the storage or use of
Hazardous Materials in any manner not permitted by any Requirements, or (iii)
the escape, disposal or release of any Hazardous Materials within or in the
vicinity of the Building (exclusive of the accidental release by any Tenant
Parties of any Hazardous Materials not introduced to the Premises by a Tenant
Party and as to which such Tenant Party has no knowledge of the presence
thereof). Nothing herein shall be deemed to prevent Tenant's use of any
Hazardous Materials customarily used in the ordinary course of office work,
provided such use is in accordance with all Requirements. Tenant shall be
responsible, at its expense, for all matters directly or indirectly based on, or
arising or resulting from the presence of Hazardous Materials in the Building
which is caused or permitted by a Tenant Party. Tenant shall provide to Landlord
copies of all communications received by Tenant with respect to any Requirements
relating to Hazardous Materials, and/or any claims made in connection therewith.
Landlord or its agents may perform environmental inspections of the Premises at
any time in accordance with Section 15.1. Landlord hereby represents to Tenant
that to Landlord's current actual knowledge, the Building does not contain any
asbestos or asbestos-containing building materials (ACBM).

          (c)  Landlord's Compliance. Landlord shall comply with (or cause to be
complied with) all Requirements applicable to the Building which are not the
obligation of Tenant, to the extent

                                       12
<PAGE>

that non-compliance would unreasonably impair Tenant's use and occupancy of the
Premises for the Permitted Use.

          (d)  Landlord's Insurance. Tenant shall not cause or permit any action
or condition that would (i) invalidate or conflict with Landlord's insurance
policies, (ii) violate applicable rules, regulations and guidelines of the Fire
Department, Fire Insurance Rating Organization or any other authority having
jurisdiction over the Building, (iii) cause an increase in the premiums of fire
insurance for the Building over that payable with respect to Comparable
Buildings, or (iv) result in Landlord's insurance companies' refusing to insure
the Building or any property therein in amounts and against risks as reasonably
determined by Landlord. If fire insurance premiums increase as a result of
Tenant's failure to comply with the provisions of this Section 8.1, Tenant shall
promptly cure such failure and shall reimburse Landlord for the increased fire
insurance premiums paid by Landlord as a result of such failure by Tenant.

     Section 8.2    Fire and Life Safety. If the Fire Insurance Rating
Organization or any Governmental Authority or any of Landlord's insurers
requires or recommends any modifications and/or alterations be made or any
additional equipment be supplied in connection with the sprinkler system or fire
alarm and life-safety system serving the Building by reason of Tenant's
business, any Alterations performed by Tenant or the location of the partitions,
Tenant's Property, or other contents of the Premises, Landlord (to the extent
outside of the Premises) or Tenant (to the extent within the Premises) shall
make such modifications and/or Alterations, and supply such additional
equipment, in either case at Tenant's expense.

                                   ARTICLE 9

                                 SUBORDINATION

     Section 9.1    Subordination and Attornment. (a) This Lease is subject and
subordinate to all Mortgages and Superior Leases, and, at the request of any
Mortgagee or Lessor, Tenant shall attorn to such Mortgagee or Lessor, its
successors in interest or any purchaser in a foreclosure sale; provided such
parties agree to recognize Tenant's interest in this Lease so long as no Event
of Default then exists.

          (b)  If a Lessor or Mortgagee or any other person or entity shall
succeed to the rights of Landlord under this Lease, whether through possession
or foreclosure action or the delivery of a new lease or deed, then at the
request of the successor landlord and upon such successor landlord's written
agreement to accept Tenant's attornment and to recognize Tenant's interest under
this Lease, Tenant shall be deemed to have attorned to and recognized such
successor landlord as Landlord under this Lease. The provisions of this Section
9.1 are self-operative and require no further instruments to give effect hereto;
provided, however, that Tenant shall promptly execute and deliver any instrument
that such successor landlord may reasonably request evidencing such attornment,
and containing such commercially reasonable terms and conditions as may be
required by such Mortgagee or Lessor, provided such terms and conditions do not
increase the Rent, materially increase Tenant's obligations or materially and
adversely affect Tenant's rights under this Lease. Upon such attornment this
Lease shall continue in full force and effect as a direct lease between such
successor landlord and Tenant upon all of the terms, conditions and covenants
set forth in this Lease except that such successor landlord shall not be

               (i)    liable for any act or omission of Landlord (except to the
extent such act or omission continues beyond the date when such successor
landlord succeeds to Landlord's interest and Tenant gives notice of such act or
omission);

               (ii)   subject to any defense, claim, counterclaim, set-off or
offsets which Tenant may have against Landlord;

                                       13
<PAGE>

               (iii)  bound by any prepayment of more than one month's Rent to
any prior landlord;

               (iv)   bound by any obligation to make any payment to Tenant
which was required to be made prior to the time such successor landlord
succeeded to Landlord's interest;

               (v)    bound by any obligation to perform any work or to make
improvements to the Premises except for (x) repairs and maintenance required to
be made by Landlord under this Lease, and (y) repairs to the Premises as a
result of damage by fire or other casualty or a partial condemnation pursuant to
the provisions of this Lease, but only to the extent that such repairs can
reasonably be made from the net proceeds of any insurance or condemnation
awards, respectively, actually made available to such successor landlord;

               (vi)   bound by any modification, amendment or renewal of this
Lease made without successor landlord's consent;

               (vii)  liable for the repayment of any security deposit or
surrender of any letter of credit, unless and until such security deposit
actually is paid or such letter of credit is actually delivered to such
successor landlord; or

               (viii) liable for the payment of any unfunded tenant improvement
allowance, refurbishment allowance or similar obligation.

          (c)  Tenant shall from time to time within 10 Business Days of request
from Landlord execute and deliver any documents or instruments that may be
reasonably required by any Mortgagee or Lessor to effectuate any subordination.

     Section 9.2    Mortgage or Superior Lease Defaults. Any Mortgagee may elect
that this Lease shall have priority over the Mortgage and, upon notification to
Tenant by such Mortgagee, this Lease shall be deemed to have priority over such
Mortgage, regardless of the date of this Lease.

     Section 9.3    Tenant's Termination Right. As long as any Superior Lease or
Mortgage exists, Tenant shall not seek to terminate this Lease by reason of any
act or omission of Landlord until (a) Tenant shall have given notice of such act
or omission to all Lessors and/or Mortgagees, and (b) a reasonable period of
time shall have elapsed following the giving of notice of such default and the
expiration of any applicable notice or grace periods (unless such act or
omission is not capable of being remedied within a reasonable period of time),
during which period such Lessors and/or Mortgagees shall have the right, but not
the obligation, to remedy such act or omission and thereafter diligently proceed
to so remedy such act or obligation. If any Lessor or Mortgagee elects to remedy
such act or omission of Landlord, Tenant shall not seek to terminate this Lease
so long as such Lessor or Mortgagee is proceeding with reasonable diligence to
effect such remedy and such remedy is effected within the later to occur of (x)
90 days or (y) 30 days after such Lessor or Mortgagee obtains possession of the
Real Property if such possession is reasonably required to effect such cure.

     Section 9.4    Provisions. The provisions of this Article 9 shall (a) inure
to the benefit of Landlord, any future owner of the Building or the Real
Property, Lessor or Mortgagee and any sublessor thereof and (b) apply
notwithstanding that, as a matter of law, this Lease may terminate upon the
termination of any such Superior Lease or Mortgage.

     Section 9.5    Non-Disturbance Agreements. Landlord hereby agrees to use
reasonable efforts to obtain for Tenant a subordination, non-disturbance and
attornment agreement (an "SNDA") from its existing Mortgagee, in the form
attached hereto as Exhibit G, provided that Landlord shall have no liability to
Tenant in the event that it is unable to obtain any such SNDA. Tenant shall
reimburse Landlord, within 30 days after demand therefor, for Landlord's out-of-
pocket costs, including reasonable attorney's fees and disbursements, incurred
in connection with such efforts. As a condition to Tenant's agreement hereunder
to subordinate Tenant's interest in this Lease to any future Mortgage and/or any
Superior Lease made between Landlord and such Mortgagee and/or Lessor, Landlord
shall obtain from each Mortgagee or Lessor an agreement, in recordable form and
in

                                       14
<PAGE>

the standard form customarily employed by such Mortgagee or Lessor, pursuant to
which such Mortgagee or Lessor 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 the rights of Tenant pursuant to this Lease to quiet and
peaceful possession of the Premises shall not be terminated, modified, affected
or disturbed by any action which such Mortgagee may take to foreclose any such
Mortgage, or which such Lessor shall take to terminate such Superior Lease, as
applicable, 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
9.1(b) hereof (any such agreement, a "Non-Disturbance Agreement").

                                  ARTICLE 10

                                   SERVICES

     Section 10.1   Access to the Premises; Elevators. Landlord shall provide
access to the Premises and passenger and freight elevator service to the
Premises 24 hours per day, 7 days per week; provided, however, Landlord may
reasonably limit elevator service during times other than Ordinary Business
Hours.

     Section 10.2   Heating. Ventilation and Air Conditioning. Landlord shall
furnish to the Premises heating, ventilation and air-conditioning ("HVAC") in
accordance with the Design Standards set forth in Exhibit D during Ordinary
Business Hours. Landlord shall have access to all air-cooling, fan, ventilating
and machine rooms and electrical closets and all other mechanical installations
of Landlord (collectively, "Mechanical Installations"), and Tenant shall not
construct partitions or other obstructions which may interfere with Landlord's
access thereto or the moving of Landlord's equipment to and from the Mechanical
Installations. No Tenant Party shall at any time enter the Mechanical
Installations or tamper with, adjust, or otherwise affect such Mechanical
Installations. Landlord shall not be responsible if the HVAC System fails to
provide cooled or heated air, as the case may be, to the Premises in accordance
with the Design Standards by reason of (i) any equipment installed by, for or on
behalf of Tenant, which has an electrical load in excess of the average
electrical load and human occupancy factors for the HVAC System as designed, or
(ii) any rearrangement of partitioning or other Alterations made or performed
by, for or on behalf of Tenant other than as constructed pursuant to (A) the
Final Plans (as such term is defined in the Workletter), or (B) plans and
specifications for Alterations proposed by Tenant which are approved by Landlord
and where such approval is not conditioned upon the installation of supplemental
HVAC Equipment. Tenant shall cooperate with Landlord and shall abide by the
rules and regulations which Landlord may reasonably prescribe for the proper
functioning and protection of the HVAC System.

     Section 10.3   Overtime Freight Elevators and HVAC. The Fixed Rent does not
include any charge to Tenant for the furnishing of any freight elevator service
or HVAC to the Premises during any periods other than Ordinary Business Hours
("Overtime Periods"). If Tenant desires any such services during Overtime
Periods, Tenant shall deliver notice to the Building office requesting such
services at least 24 hours prior to the time Tenant requests such services to be
provided; provided, however, that Landlord shall use reasonable efforts to
arrange such service on such shorter notice as Tenant shall provide. If Landlord
furnishes freight elevator or HVAC service during Overtime Periods, Tenant shall
pay to Landlord the cost thereof at the then established rates for such services
in the Building.

     Section 10.4   Cleaning. Landlord shall cause the Premises (excluding any
portions thereof used for the storage, preparation, service or consumption of
food or beverages) to be cleaned, substantially in accordance with the standards
set forth in Exhibit E. Any areas of the Premises requiring additional cleaning
such as areas used for preparation or consumption of food, computer rooms, mail
rooms and trading floors shall be cleaned, at Tenant's expense, by Landlord's
cleaning contractor, at rates which shall be competitive with rates of other
cleaning contractors providing

                                       15
<PAGE>

comparable services to Comparable Buildings. Landlord's cleaning contractor and
its employees shall have access to the Premises at all times except during
Ordinary Business Hours.

     Section 10.5   Water. Landlord shall provide water in the core lavatories
on each floor of the Building and to the pantries within the Premises; provided
that the cost of installing any water lines to such pantries and the cost of
acquiring and installing any necessary hot water boosters, shall be solely for
the account of Tenant. If Tenant requires water for any additional purposes,
Tenant shall pay for the cost of bringing water to the Premises and Landlord may
install a meter to measure the water. Tenant shall pay the cost of such
installation, and for all maintenance, repairs and replacements thereto, and for
the reasonable charges of Landlord for the water consumed.

     Section 10.6   Refuse Removal. Landlord shall provide refuse removal
services at the Building. Tenant shall pay to Landlord, within 10 Business Days
after delivery of an invoice therefor, Landlord's reasonable charge for such
removal to the extent that the refuse generated by Tenant exceeds the refuse
customarily generated by general office tenants. Tenant shall not dispose of any
refuse in the Common Areas, and if Tenant does so, Tenant shall be liable for
Landlord's reasonable charge for such removal.

     Section 10.7   Telecommunications Riser Capacity. Landlord shall make
available to Tenant for its non-exclusive use reasonably sufficient
telecommunication riser access at a riser terminating at the telecommunications
closets located on each floor of the Premises. The riser provided to Tenant
shall provide reasonably sufficient access to allow Tenant to bring T1/T3 lines
to the Premises. Tenant shall be responsible, at its sole cost and expense
(including the cost of installing any required conduits) of installing such
T1/T3 lines.

     Section 10.8   Directory. Within a reasonable time following the
Commencement Date, which may not be until March 31, 2000, Landlord shall install
in the main ground floor lobby of the Building a computerized directory wherein
the Building's tenants shall be listed with a capacity for up to 25 listings per
floor for Tenant (including its operating divisions, Portfolio Companies (as
hereinafter defined), permitted assignees and sublessees, Related Corporations
and others permitted to occupy the Premises hereunder). Until such time as the
computerized directory is so installed, Landlord shall identify Tenant's
presence within the Building through other reasonable means. Tenant shall be
entitled to a proportionate share of such listings. From time to time, but not
more frequently than monthly, Landlord shall reprogram the computerized
directory to reflect such changes in the listings therein as Tenant shall
request.

     Section 10.9   Service Interruptions. Landlord reserves the right to
suspend any service when necessary, by reason of Unavoidable Delays, accidents
or emergencies, or for Restorative Work which, in Landlord's reasonable
judgment, are necessary or appropriate until such Unavoidable Delay, accident or
emergency shall cease or such Restorative Work is completed and Landlord shall
not be liable for any interruption, curtailment or failure to supply services.
Landlord shall use reasonable efforts to restore such service, remedy such
situation and minimize any interference with Tenant's business. The exercise of
any such right or the occurrence of any such failure by Landlord shall not
constitute an actual or constructive eviction, in whole or in part, entitle
Tenant to any compensation, abatement or diminution of Rent, relieve Tenant from
any of its obligations under this Lease, or impose any liability upon Landlord
or its agents by reason of inconvenience to Tenant, or interruption of Tenant's
business, or otherwise.

                                  ARTICLE 11

                      INSURANCE; PROPERTY LOSS OR DAMAGE

     Section 11.1   Tenant's Insurance. (a) Tenant, at its expense, shall obtain
and keep in full force and effect during the Term:

                                       16
<PAGE>

               (i)    a policy of commercial general liability insurance on an
occurrence basis against claims for personal injury, death and/or property
damage occurring in or about the Building, under which Tenant is named as the
insured and Landlord, Landlord's Agent and any Lessors and any Mortgagees whose
names have been furnished to Tenant are named as additional insureds (the
"Insured Parties"). Such insurance shall provide primary coverage without
contribution from any other insurance carried by or for the benefit of the
Insured Parties, and Tenant shall obtain blanket broad-form contractual
liability coverage to insure its indemnity obligations set forth in Article 26.
The minimum limits of liability shall be a combined single limit with respect to
each occurrence in an amount of not less than $5,000,000.00; provided, however,
that Landlord shall retain the right to require Tenant to increase such coverage
from time to time to that amount of insurance which in Landlord's reasonable
judgment is then being customarily required by landlords for similar office
space in Comparable Buildings. The deductible or self insured retention for such
policy shall not exceed $10,000.00;

               (ii)   insurance against loss or damage by fire, and such other
risks and hazards as are insurable under then available standard forms of "all
risk" property insurance policies with extended coverage, insuring Tenant's
Property and all Alterations and improvements to the Premises (including the
Improvements constructed pursuant to the Workletter) to the extent such
Alterations and improvements exceed the cost of the Improvements typically
performed in connection with the initial occupancy of general office tenants in
Comparable Buildings ("Building Standard Installations"), for the full insurable
value thereof or replacement cost thereof, having a deductible amount, if any,
as reasonably determined by Landlord;

               (iii)  during the performance of any Alteration, until completion
thereof, Builder's Risk insurance on an "all risk" basis and on a completed
value form including a Permission to Complete and Occupy endorsement, for full
replacement value covering the interest of Landlord and Tenant (and their
respective contractors and subcontractors) in all work incorporated in the
Building and all materials and equipment in or about the Premises;

               (iv)   Workers' Compensation Insurance, as required by law;

               (v)    Business Interruption Insurance; and

               (vi)   such other insurance in such amounts as the Insured
Parties may reasonably require from time to time.

          (b)  All insurance required to be carried by Tenant (i) shall contain
a provision that (x) no act or omission of Tenant shall affect or limit the
obligation of the insurance company to pay the amount of any loss sustained, and
(y) shall be noncancellable and/or no material change in coverage shall be made
thereto unless the Insured Parties receive 30 days' prior notice of the same, by
certified mail, return receipt requested, and (ii) shall be effected under valid
and enforceable policies issued by reputable insurers permitted to do business
in the State of California and rated in Best's Insurance Guide, or any successor
thereto as having a "Best's Rating" of "A-" and a "Financial Size Category" of
at least "X" or, if such ratings are not then in effect, the equivalent thereof
or such other financial rating as Landlord may at any time consider appropriate.

          (c)  On or prior to the Commencement Date, Tenant shall deliver to
Landlord appropriate policies of insurance, including evidence of waivers of
subrogation required to be carried pursuant to this Article 11. Evidence of each
renewal or replacement of a policy shall be delivered by Tenant to Landlord at
least 10 days prior to the expiration of such policy. In lieu of the policy of
insurance required to be delivered to Landlord pursuant to this Article 11 (the
"Policy"), Tenant may deliver to Landlord a certification from Tenant's
insurance company (on the form currently designated "Acord 27", or the
equivalent) which shall be binding on Tenant's insurance company, and which
shall expressly provide that such certification (i) conveys to the Insured
Parties all the rights and privileges afforded under the Policy as primary
insurance, and (ii) contains an unconditional obligation of the insurance
company to advise all Insured Parties in writing by certified mail, return
receipt requested,

                                       17
<PAGE>

at least 30 days in advance of any termination or change to the Policy that
would affect the interest of any of the Insured Parties.

     Section 11.2   Waiver of Subrogation. Landlord and Tenant shall each
procure an appropriate clause in or endorsement to any property insurance
covering the Premises, the Building and personal property, fixtures and
equipment located therein, wherein the insurer waives subrogation or consents to
a waiver of right of recovery, and Landlord and Tenant 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 to the
extent covered by such property insurance; provided, however, that the release,
discharge, exoneration and covenant not to sue contained herein shall be limited
by and be coextensive with the terms and provisions of the waiver of subrogation
or waiver of right of recovery. Tenant acknowledges that Landlord shall not
carry insurance on, and shall not be responsible for, (i) damage to any Above
Building Standard Installations, (ii) Tenant's Property, and (iii) any loss
suffered by Tenant due to interruption of Tenant's business.

     Section 11.3   Restoration. (a) If the Premises are damaged by fire or
other casualty, or if the Building is damaged such that Tenant is deprived of
reasonable access to the Premises, the damage shall be repaired by Landlord, to
substantially the condition of the Premises prior to the damage (or to such
other condition as Tenant may prescribe which is reasonably acceptable to
Landlord, but in no event less than restoring Building Standard Installations) ,
subject to the provisions of any Mortgage or Superior Lease, but Landlord shall
have no obligation to repair or restore (i) Tenant's Property or (ii) except as
provided in Section 11.3(b), any Above Building Standard Installations. So long
as Tenant is not in default beyond applicable grace or notice provisions in the
payment or performance of its obligations under this Section 11.3, and provided
Tenant timely delivers to Landlord either Tenant's Restoration Payment (as
hereinafter defined) or the Restoration Security (as hereinafter defined) or
Tenant expressly waives any obligation of Landlord to repair or restore any of
Tenant's Above Building Standard Installations, then until the restoration of
the Premises is Substantially Completed or would have been Substantially
Completed but for Tenant Delay, Fixed Rent, Tenant's Tax Payment and Tenant's
Operating Payment shall be reduced in the proportion by which the area of the
part of the Premises which is not usable (or accessible ) and is not used by
Tenant bears to the total area of the Premises.

          (b)  As a condition precedent to Landlord's obligation to repair or
restore any Above Building Standard Installations, Tenant shall (i) pay to
Landlord within 30 days of written demand a sum ("Tenant's Restoration Payment")
equal to the amount, if any, by which (A) the cost, as estimated by a reputable
independent contractor designated by Landlord, of repairing and restoring all
Alterations and improvements in the Premises to their condition prior to the
damage, exceeds (B) the cost of restoring the Premises with Building Standard
Installations, or (ii) furnish to Landlord security (the "Restoration Security")
in form and amount reasonably acceptable to Landlord to secure Tenant's
obligation to pay all costs in excess of restoring the Premises with Building
Standard Installations. To the extent practicable, the Restoration Security may
be converted to cash and utilized to fund Tenant's obligation for Tenant's Above
Building Standard Installations. If Tenant shall fail to deliver to Landlord
either (1) Tenant's Restoration Payment or the Restoration Security, as
applicable, or (2) a written waiver by Tenant, in form satisfactory to Landlord,
of all of Landlord's obligations to repair or restore any of the Above Building
Standard Installations, in either case within 30 days after Landlord's demand
therefore, Landlord shall have no obligation to restore any Above Building
Standard Installations and Tenant's abatement of Fixed Rent, Tenant's Tax
Payment and Tenant's Operating Payment shall cease when the restoration of the
Premises (other than any Above Building Standard Installations) is Substantially
Complete.

     Section 11.4   Landlord's Termination Right. Notwithstanding anything to
the contrary contained in Section 11.3, if the Premises are totally damaged or
are rendered wholly untenantable, or if the Building shall be so damaged that,
in Landlord's reasonable opinion, substantial alteration, demolition, or
reconstruction of the Building shall be required (whether or not the Premises
are so damaged or rendered untenantable), then in either of such events,
Landlord may, not later than 60

                                       18
<PAGE>

days following the date of the damage, terminate this Lease by notice to Tenant,
provided that if the Premises are not damaged, Landlord may not terminate this
Lease unless Landlord similarly terminates the leases of other tenants in the
Building aggregating at least 50% of the portion of the Building occupied for
office purposes immediately prior to such damage. If this Lease is so
terminated, (a) the Term shall expire upon the 30th day after such notice is
given, (b) Tenant shall vacate the Premises and surrender the same to Landlord,
(c) Tenant's liability for Rent shall cease as of the date of the damage, and
(d) any prepaid Rent for any period after the date of the damage shall be
refunded by Landlord to Tenant.

     Section 11.5   Tenant's Termination Right. If the Premises are totally
damaged and are thereby rendered wholly untenantable, or if the Building shall
be so damaged that Tenant is deprived of reasonable access to the Premises, and
if Landlord elects to restore the Premises, Landlord shall, within 60 days
following the date of the damage, cause a contractor or architect selected by
Landlord to give notice (the "Restoration Notice") to Tenant of the date by
which such contractor or architect estimates the restoration of the Premises
(excluding any Above Building Standard Installations) shall be Substantially
Completed. If such date, as set forth in the Restoration Notice, is more than 12
months from the date of such damage, then Tenant shall have the right to
terminate this Lease by giving notice (the "Termination Notice") to Landlord not
later than 30 days following delivery of the Restoration Notice to Tenant. If
Tenant delivers a Termination Notice, this Lease shall be deemed to have
terminated as of the date of the giving of the Termination Notice, in the manner
set forth in the second sentence of Section 11.4.

     Section 11.6   Final 18 Months. Notwithstanding anything to the contrary in
this Article 11, if any damage during the final 18 months of the Term renders
the Premises wholly untenantable, either Landlord or Tenant may terminate this
Lease by notice to the other party within 30 days after the occurrence of such
damage and this Lease shall expire on the 30th day after the date of such
notice. For purposes of this Section 11.6, the Premises shall be deemed wholly
untenantable if Tenant shall be precluded from using more than 50% of the
Premises for the conduct of its business and Tenant's inability to so use the
Premises is reasonably expected to continue for more than 90 days.

     Section 11.7   Landlord's Liability. Any Building employee 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 such property, or for the loss of
or damage to any property of Tenant by theft or otherwise. None of the Insured
Parties shall be liable for any injury or damage to persons or property or
interruption of Tenant's business resulting from fire or other casualty, any
damage caused by other tenants or persons in the Building or by construction of
any private, public or quasi-public work, or any latent defect in the Premises
or in the Building (except that Landlord shall be required to repair the same to
the extent provided in Article 5). No penalty shall accrue for delays which may
arise by reason of adjustment of fire insurance on the part of Landlord or
Tenant, or for any Unavoidable Delays arising from any repair or restoration of
any portion of the Building, provided that Landlord shall use reasonable efforts
to minimize interference with Tenant's use and occupancy of the Premises during
the performance of any such repair or restoration.

     Section 11.8   Landlord's Insurance. Landlord shall, from and after the
Effective Date and until the Expiration Date, maintain in effect the following
insurance: (i) fire and "all risk" insurance providing coverage in the event of
fire, vandalism, malicious mischief and all other risks normally covered by "all
risk" policies in the area of the Building, covering the Building (excluding the
property required to be insured by Tenant pursuant to Section 11.1) in an amount
not less than ninety-five percent (95%) of the full replacement value (less
commercially reasonable deductibles which as of the Effective Date is Twenty-
Five Thousand Dollars ($25,000.00) but is subject to periodic change over the
Term) of the Building excluding foundations, footings and other below-grade
structural elements; and (ii) commercial general liability insurance or the
equivalent in the amount of at least Five Million Dollars ($5,000,000.00),
against claims of bodily injury, personal injury or property damage arising out
of Landlord's operations, assumed liabilities, contractual liabilities, or use
of the Building and Common

                                       19
<PAGE>

Areas. Such insurance may be carried under blanket or umbrella insurance
policies. Upon written request from Tenant, but no more than one (1) time during
any calendar year, Landlord shall provide Tenant with evidence that Landlord is
carrying the insurance Landlord is required to maintain pursuant to this Section
11.8

                                  ARTICLE 12

                                EMINENT DOMAIN

     Section 12.1   Taking. (a) Total Taking. If all or substantially all of the
Real Property, the Building or the Premises shall be acquired or condemned for
any public or quasi-public purpose (a "Taking"), this Lease shall terminate and
the Term shall end as of the date of the vesting of title and Rent shall be
prorated and adjusted as of such date.

          (b)  Partial Taking. Upon a Taking of only a part of the Real
Property, the Building or the Premises then, except as hereinafter provided in
this Article 12, this Lease shall continue in full force and effect, provided
that from and after the date that is the earlier of Tenant's deprivation of use
or the date of the vesting of title, Fixed Rent and Tenant's Proportionate Share
shall be modified to reflect the reduction of the Premises and/or the Building
as a result of such Taking.

          (c)  Landlord's Termination Right. Whether or not the Premises are
affected, Landlord may, by notice to Tenant, within 60 days following the date
upon which Landlord receives notice of the Taking of all or a material portion
of the Real Property, the Building or the Premises, terminate this Lease,
provided that Landlord elects to terminate leases (including this Lease)
affecting at least 50% of the rentable area of the Building.

          (d)  Tenant's Termination Right. If the part of the Real Property so
Taken contains more than 20% of the total area of the Premises occupied by
Tenant immediately prior to such Taking, or if, by reason of such Taking, Tenant
no longer has reasonable means of access to the Premises, Tenant may terminate
this Lease by notice to Landlord given within 30 days following the date upon
which Tenant is given notice of such Taking. If Tenant so notifies Landlord,
this Lease shall end and expire upon the 30th day following the giving of such
notice. If a part of the Premises shall be so Taken and this Lease is not
terminated in accordance with this Section 12.1 Landlord, without being required
to spend more than it collects as an award, shall, subject to the provisions of
any Mortgage or Superior Lease, restore that part of the Premises not so Taken
to a self-contained rental unit substantially equivalent (with respect to
character, quality, appearance and services) to that which existed immediately
prior to such Taking, excluding Tenant's Property and any Above Building
Standard Installations.

          (e)  Apportionment of Rent. Upon any termination of this Lease
pursuant to the provisions of this Article 12, Rent shall be apportioned as of,
and shall be paid or refunded up to and including, the date of such termination.

     Section 12.2   Awards. Upon any Taking, Landlord shall receive the entire
award for any such Taking, and Tenant shall have no claim against Landlord or
the condemning authority for the value of any unexpired portion of the Term or
Tenant's Alterations; and Tenant hereby assigns to Landlord all of its right in
and to such award. Nothing contained in this Article 12 shall be deemed to
prevent Tenant from making a separate claim in any condemnation proceedings for
the then value of any Tenant's Property or Above Building Standard Installations
included in such Taking and for any moving expenses, provided any such award is
in addition to, and does not result in a reduction of, the award made to
Landlord.

     Section 12.3   Temporary Taking. If all or any part of the Premises is
Taken temporarily during the Term for any public or quasi-public use or purpose,
Tenant shall give prompt notice to Landlord and the Term shall not be reduced or
affected in any way and Tenant shall continue to pay all Rent payable by Tenant
without reduction or abatement and to perform all of its other obligations

                                       20
<PAGE>

under this Lease, except to the extent prevented from doing so by the condemning
authority, and Tenant shall be entitled to receive any award or payment from the
condemning authority for such use, which shall be received, held and applied by
Tenant as a trust fund for payment of the Rent falling due.

                                  ARTICLE 13

                           ASSIGNMENT AND SUBLETTING

     Section 13.1  Consent Requirements.

          (a)  No Assignment or Subletting. Except as expressly set forth
herein, Tenant shall not assign, mortgage, pledge, encumber, or otherwise
transfer this Lease, whether by operation of law or otherwise, and shall not
sublet, or permit, or suffer the Premises or any part thereof to be used or
occupied by others (whether for desk space, mailing privileges or otherwise),
without Landlord's prior consent in each instance. Any assignment, sublease,
mortgage, pledge, encumbrance or transfer in contravention of the provisions of
this Article 13 shall be void and shall constitute an Event of Default.

          (b)  Collection of Rent. If, without Landlord's consent, this Lease is
assigned, or any part of the Premises is sublet or occupied by anyone other than
Tenant or this Lease is encumbered (by operation of law or otherwise), Landlord
may collect rent from the assignee, subtenant or occupant, and apply the net
amount collected to the Rent herein reserved. No such collection shall be deemed
a waiver of the provisions of this Article 13, an acceptance of the assignee,
subtenant or occupant as tenant, or a release of Tenant from the performance of
Tenant's covenants hereunder, and in all cases Tenant shall remain fully liable
for its obligations under this Lease.

          (c)  Further Assignment/Subletting. Landlord's consent to any
assignment or subletting shall not relieve Tenant from the obligation to obtain
Landlord's consent to any further assignment or subletting. In no event shall
any permitted subtenant assign or encumber its sublease or further sublet any
portion of its sublet space, or otherwise suffer or permit any portion of the
sublet space to be used or occupied by others.

     Section 13.2   Tenant's Notice. If Tenant desires to assign this Lease or
sublet all or any portion of the Premises, Tenant shall give notice thereof to
Landlord, which shall be accompanied by (a) with respect to an assignment of
this Lease, the date Tenant desires the assignment to be effective, and (b) with
respect to a sublet of all or a part of the Premises, a description of the
portion of the Premises to be sublet. Such notice shall be deemed an offer from
Tenant to Landlord of the right, at Landlord's option, (1) to terminate this
Lease with respect to such space as Tenant proposes to sublease (the "Partial
Space"), upon the terms and conditions hereinafter set forth, or (2) if the
proposed transaction is an assignment of this Lease or a subletting of two (2)
full floors or more of the Premises, to terminate this Lease with respect to the
entire Premises. Such option may be exercised by notice from Landlord to Tenant
within 30 days after delivery of Tenant's notice. If Landlord exercises its
option to terminate all or a portion of this Lease, (a) this Lease shall end and
expire with respect to all or a portion of the Premises, as the case may be, on
the date that such assignment or sublease was to commence, (b) Rent shall be
apportioned, paid or refunded as of such date, (c) Tenant, upon Landlord's
request, shall enter into an amendment of this Lease ratifying and confirming
such total or partial termination, and setting forth any appropriate
modifications to the terms and provisions hereof, and (d) Landlord shall be free
to lease the Premises (or any part thereof) to Tenant's prospective assignee or
subtenant. Tenant shall pay all costs to make the Partial Space a self-contained
rental unit.

     Section 13.3   Conditions to Assignment/Subletting. (a) If Landlord does
not exercise its termination option provided under Section 13.2, and provided
that no Event of Default then exists, Landlord's consent to the proposed
assignment or subletting shall not be unreasonably withheld or delayed. Such
consent shall be granted or denied as soon as practicable and in no case more
than

                                       21
<PAGE>

30 days after delivery to Landlord of (i) a true and complete statement
reasonably detailing the identity of the proposed assignee or subtenant
("Transferee"), the nature of its business and its proposed use of the Premises,
(ii) current financial information with respect to the Transferee, including its
most recent financial statements, and (iii) any other information Landlord may
reasonably request, provided that:

                    (A)  in Landlord's reasonable judgment, the Transferee is
     engaged in a business or activity, and the Premises will be used in a
     manner, which (1) is in keeping with the then standards of the Building,
     (2) is for the Permitted Uses, and (3) does not violate any restrictions
     set forth in this Lease, any Mortgage or Superior Lease or any negative
     covenant as to use of the Premises required by any other lease in the
     Building;

                    (B)  the Transferee is reputable with sufficient financial
     means to perform all of its obligations under this Lease or the sublease,
     as the case may be;

                    (C)  if Landlord has, or reasonably expects to have within 2
     months thereafter, comparable space available in the Building (it being
     understood that floors 17 through 40 are not comparable space), neither the
     Transferee nor any person which, directly or indirectly, controls, is
     controlled by, or is under common control with, the Transferee is then an
     occupant of the Building;

                    (D)  the Transferee is not a person or entity (or affiliate
     of a person or entity) with whom Landlord is then or has been within the
     prior 6 months negotiating in connection with the rental of space in the
     Building; provided that the provisions of this Section 13.3(a)(A) shall not
     apply if the proposed Transferee is Engage Technologies, Inc. ("Engage") or
     a Related Corporation (as hereinafter defined);

                    (E)  there shall be not more than 2 subtenants in each floor
     of the Premises;

                    (F)  the aggregate consideration to be paid by the
     Transferee under the terms of the proposed sublease shall not be less than
     90% of the fixed rent at which Landlord is then offering to lease other
     space in the Building (the "Market Sub-rent") determined as though the
     Premises were vacant and taking into account (1) the length of the term of
     the proposed sublease, (2) any rent concessions granted to Transferee, and
     (3) the cost of any Alterations being performed for the Transferee;

                    (G)  Tenant shall, within 30 days of demand, reimburse
     Landlord for all reasonable expenses incurred by Landlord in connection
     with such assignment or sublease, including any investigations as to the
     acceptability of the Transferee and all legal costs reasonably incurred in
     connection with the granting of any requested consent;

                    (H)  Tenant shall not list the Premises to be sublet or
     assigned with a broker, agent or other entity or otherwise offer the
     Premises for subletting at a rental rate less than the Market Sub-rent; and

                    (I)  the Transferee shall not be entitled, directly or
     indirectly, to diplomatic or sovereign immunity, regardless of whether the
     Transferee agrees to waive such diplomatic or sovereign immunity, and shall
     be subject to the service of process in, and the jurisdiction of the courts
     of, the City and County of San Francisco and State of California.

          (b)  With respect to each and every subletting and/or assignment
approved by Landlord under the provisions of this Lease:

                                       22
<PAGE>

               (i)    the form of the proposed assignment or sublease shall be
reasonably satisfactory to Landlord;

               (ii)   no sublease shall be for a term ending later than one day
prior to the Expiration Date;

               (iii)  except as otherwise provided in Section 13.7, no
Transferee shall take possession of any part of the Premises, until an executed
counterpart of such sublease or assignment has been delivered to Landlord and
approved by Landlord as provided in Section 13.3(a);

               (iv)   if an Event of Default occurs prior to the effective date
of such assignment or subletting and is continuing and yet uncured on the date
that would otherwise be such effective date, then Landlord's consent thereto, if
previously granted, shall be immediately deemed revoked without further notice
to Tenant, and any such deemed unconsented to assignment or subletting shall
constitute a further Event of Default hereunder; and

               (v)    each sublease shall be subject and subordinate to this
Lease and to the matters to which this Lease is or shall be subordinate; and
Tenant and each Transferee shall be deemed to have agreed that upon the
occurrence and during the continuation of an Event of Default hereunder, Tenant
has hereby assigned to Landlord, and Landlord may, at its option, accept such
assignment of, all right, title and interest of Tenant as sublandlord under such
sublease, together with all modifications, extensions and renewals thereof then
in effect and such Transferee shall, at Landlord's option, attorn to Landlord
pursuant to the then executory provisions of such sublease, except that Landlord
shall not be (A) liable for any previous act or omission of Tenant under such
sublease, (B) subject to any counterclaim, offset or defense not expressly
provided in such sublease, which theretofore accrued to such Transferee against
Tenant, (C) bound by any previous modification of such sublease not consented to
by Landlord or by any prepayment of more than one month's rent, (D) bound to
return such Transferee's security deposit, if any, except to the extent Landlord
shall receive actual possession of such deposit and such Transferee shall be
entitled to the return of all or any portion of such deposit under the terms of
its sublease, or (E) obligated to make any payment to or on behalf of such
Transferee, or to perform any work in the subleased space or the Building, or in
any way to prepare the subleased space for occupancy, beyond Landlord's
obligations under this Lease. The provisions of this Section 13.3(b)(v) shall be
self-operative, and no further instrument shall be required to give effect to
this provision, provided that the Transferee shall execute and deliver to
Landlord any instruments Landlord may reasonably request to evidence and confirm
such subordination and attornment.

     Section 13.4   Binding on Tenant; Indemnification of Landlord.
Notwithstanding any assignment or subletting or any acceptance of rent by
Landlord from any Transferee, Tenant shall remain fully liable for the payment
of all Rent due and for the performance of all the covenants, terms and
conditions contained in this Lease on Tenant's part to be observed and
performed, and any default under any term, covenant or condition of this Lease
by any Transferee or anyone claiming under or through any Transferee shall be
deemed to be a default under this Lease by Tenant. Tenant shall indemnify,
defend, protect and hold harmless Landlord from and against any and all Losses
resulting from any claims that may be made against Landlord by the Transferee or
anyone claiming under or through any Transferee or by any brokers or other
persons claiming a commission or similar compensation in connection with the
proposed assignment or sublease, irrespective of whether Landlord shall give or
decline to give its consent to any proposed assignment or sublease, or if
Landlord shall exercise any of its options under this Article 13.

     Section 13.5   Tenant's Failure to Complete. If Landlord consents to a
proposed assignment or sublease and Tenant fails to execute and deliver to
Landlord such assignment or sublease within 90 days after the giving of such
consent, then Tenant shall again comply with all of the provisions and
conditions of Section 13.2 before assigning this Lease or subletting all or part
of the Premises.

     Section 13.6   Profits. If Tenant enters into any assignment or sublease
permitted hereunder or consented to by Landlord, Tenant shall, within 60 days of
Landlord's consent to such assignment or

                                       23
<PAGE>

sublease, deliver to Landlord a list of Tenant's reasonable third-party
brokerage fees, legal fees and architectural fees paid or to be paid in
connection with such transaction and any actual costs incurred by Tenant in
separately demising the subleased space (collectively, "Transaction Costs"),
together with a list of all of Tenant's Property to be transferred to such
Transferee. The Transaction Costs shall be amortized, on a straight-line basis,
over the term of any sublease. Tenant shall deliver to Landlord evidence of the
payment of such Transaction Costs promptly after the same are paid. In
consideration of such assignment or subletting, Tenant shall pay to Landlord:

          (a)  In the case of an assignment, as and when paid, 50% of all sums
and other consideration paid to Tenant by the Transferee for or by reason of
such assignment attributable to Tenant's interest under this Lease (including
sums paid for the sale or rental of Tenant's Property, less, in the case of a
sale thereof, the then fair market value thereof, as reasonably determined by
Landlord) after first deducting the Transaction Costs; or

          (b)  In the case of a sublease, 50% of any consideration payable under
the sublease to Tenant by the Transferee which exceeds on a per square foot
basis the Fixed Rent accruing during the term of the sublease in respect of the
subleased space (together with any sums paid for the sale or rental of Tenant's
Property, less, in the case of the sale thereof, the then fair market value
thereof, as reasonably determined by Landlord) after first deducting the monthly
amortized amount of Transaction Costs. The sums payable under this clause shall
be paid by Tenant to Landlord monthly as and when paid by the subtenant to
Tenant.

     Section 13.7   Transfers. (a) Related Entities. Sections 13.1, 13.2 or
13.3(a) do not apply to Section 13.7 Transfers. If Tenant is a corporation, the
transfer (by one or more transfers) of a majority of the stock of Tenant shall
be deemed a voluntary assignment of this Lease; provided, however, that the
provisions of this Article 13 shall not apply to the transfer of shares of stock
of Tenant if and so long as Tenant is publicly traded on a nationally recognized
stock exchange or electronic trading system. For purposes of this Section 13.7
the term "transfers" shall be deemed to include the issuance of new stock which
results in a majority of the stock of Tenant being held by a person or entity
which does not hold a majority of the stock of Tenant on the Effective Date. If
Tenant is a limited liability company, partnership, trust, or any other legal
entity, the transfer (by one or more transfers) of a majority of the beneficial
ownership interests in such entity, however characterized, shall be deemed a
voluntary assignment of this Lease. The provisions of Sections 13.1, 13.2 or
13.3(a) shall not apply to transactions with a corporation or other legal entity
into or with which Tenant is merged or consolidated or to which substantially
all of Tenant's assets are transferred so long as (i) such transfer was made for
a legitimate independent business purpose and not for the purpose of
transferring this Lease, (ii) either the successor to Tenant has a net worth
computed in accordance with generally accepted accounting principles at least
equal to the net worth of Tenant immediately prior to such merger, consolidation
or transfer, or if CMGI, Inc. is the surviving entity and subsequent to such
transaction the financial condition of Tenant will not be materially impaired,
and (iii) proof satisfactory to Landlord of such net worth is delivered to
Landlord at least 10 days prior to the effective date of any such transaction,
or within 5 Business Days thereafter in connection with a confidential
transaction, the existence of which is not within the public domain and which
either pursuant to applicable Requirements or by agreement with the other party
thereto must remain confidential. Tenant may also, upon prior notice to
Landlord, permit any corporation or other business entity which controls, is
controlled by, or is under common control with the original Tenant (a "Related
Corporation") to sublet or otherwise occupy all or part of the Premises for the
Permitted Uses or take an assignment of Tenant's interest under this Lease,
provided the Related Corporation is in Landlord's reasonable judgment of a
character and engaged in a business which is in keeping with the standards for
the Building and for so long as such entity remains a Related Corporation. For
so long as Greenwitch LLC, iCAST, Engage and/or Activate (collectively,
"Portfolio Companies") are Related Corporations, Landlord hereby consents to the
Portfolio Companies' use and occupancy of the Premises. Such sublease shall not
be deemed to vest in any such Related Corporation any right or interest in this
Lease nor shall any such sublease or assignment relieve, release, impair or
discharge any of Tenant's obligations hereunder. For the purposes hereof,
"control" shall be deemed

                                       24
<PAGE>

to mean ownership of not less than 50% of all of the voting stock of such
corporation or not less than 50% of all of the legal and equitable interest in
any other business entity if Tenant is not a corporation. Notwithstanding the
foregoing, Tenant shall have no right to assign this Lease or sublease all or
any portion of the Premises without Landlord's consent pursuant to this Section
13.7 if Tenant is not the initial Tenant herein named or a person or entity who
acquired Tenant's interest in this Lease in a transaction approved by Landlord
pursuant to this Section 13.7 or is otherwise permitted hereunder without the
requirement of first obtaining Landlord's consent. In connection with Landlord's
review of any non-public documents and information furnished by Tenant in
connection with a proposed transaction with a Related Corporation, Landlord
agrees to hold such information in confidence and not to disclose such
information to third parties, other than its attorneys, partners and Mortgagees.

          (b)  Applicability. The limitations set forth in this Section 13.7
shall apply to Transferee(s) of this Lease, if any, and any transfer by any such
entity in violation of this Section 13.7 shall be a transfer in violation of
Section 13.1.

          (c)  Modifications, Takeover Agreements. Any modification, amendment
or extension of a sublease and/or any other agreement by which a landlord of a
building other than the Building agrees to assume the obligations of Tenant
under this Lease shall be deemed a sublease for the purposes of Section 13.1
hereof.

     Section 13.8   Assumption of Obligations. No assignment or transfer shall
be effective unless and until the Transferee executes, acknowledges and delivers
to Landlord an agreement in form and substance reasonably satisfactory to
Landlord whereby the assignee (a) assumes Tenant's obligations under this Lease
and (b) agrees that, notwithstanding such assignment or transfer, the provisions
of Section 13.1 hereof shall be binding upon it in respect of all future
assignments and transfers subject to the rights afforded by Section 13.7.

     Section 13.9   Tenant's Liability. The joint and several liability of
Tenant and any successors-in-interest of Tenant and the due performance of
Tenant's obligations under this Lease shall not be discharged, released or
impaired by any agreement or stipulation made by Landlord, or any grantee or
assignee of Landlord, extending the time, or modifying any of the terms and
provisions of this Lease, or by any waiver or failure of Landlord, or any
grantee or assignee of Landlord, to enforce any of the terms and provisions of
this Lease.

     Section 13.10  Listings in Building Directory. The listing of any name
other than that of Tenant on the doors of the Premises, the Building directory
or elsewhere shall not vest any right or interest in this Lease or in the
Premises, nor be deemed to constitute Landlord's consent to any assignment or
transfer of this Lease or to any sublease of the Premises or to the use or
occupancy thereof by others. Any such listing shall constitute a privilege
revocable in Landlord's discretion by notice to Tenant.

     Section 13.11  Lease Disaffirmance or Rejection. If at any time after an
assignment by Tenant named herein, this Lease is not affirmed or is rejected in
any bankruptcy proceeding or any similar proceeding, or upon a termination of
this Lease due to any such proceeding, Tenant named herein, upon request of
Landlord given after such disaffirmance, rejection or termination (and actual
notice thereof to Landlord in the event of a disaffirmance or rejection or in
the event of termination other than by act of Landlord), shall (a) pay to
Landlord all Rent and other charges due and owing by the assignee to Landlord
under this Lease to and including the date of such disaffirmance, rejection or
termination, and (b) as "tenant," enter into a new lease of the Premises with
Landlord for a term commencing on the effective date of such disaffirmance,
rejection or termination and ending on the Expiration Date, at the same Rent and
upon the then executory terms, covenants and conditions contained in this Lease,
except that (i) the rights of Tenant named herein under the new lease shall be
subject to the possessory rights of the assignee under this Lease and the
possessory rights of any persons claiming through or under such assignee or by
virtue of any statute or of any order of any court, (ii) such new lease shall
require all defaults existing under this Lease to be cured by Tenant named
herein with due diligence, and (iii) such new lease shall require Tenant named
herein to pay all

                                       25
<PAGE>

Rent which, had this Lease not been so disaffirmed, rejected or terminated,
would have become due under the provisions of this Lease after the date of such
disaffirmance, rejection or termination with respect to any period prior
thereto. If Tenant named herein defaults in its obligations to enter into such
new lease for a period of 10 days after Landlord's request, then, in addition to
all other rights and remedies by reason of default, either at law or in equity,
Landlord shall have the same rights and remedies against Tenant named herein as
if it had entered into such new lease and such new lease had thereafter been
terminated as of the commencement date thereof by reason of Tenant's default
thereunder.

                                  ARTICLE 14

                                  ELECTRICITY

     Section 14.1   Electricity. Subject to any Requirements or any public
utility rules or regulations governing energy consumption, Landlord shall make
or cause to be made, customary arrangements with public utilities and/or public
agencies to furnish electric current to the Premises for Tenant's use in
accordance with the Design Standards. If Landlord reasonably determines by the
use of an electrical consumption survey or by other reasonable means that Tenant
is using electric current (including overhead fluorescent fixtures) in excess of
 .60 kilowatt hours per square foot of usable area in the Premises per month
("Excess Electrical Usage"), then Landlord shall have the right to charge Tenant
an amount equal to Landlord's reasonable estimate of Tenant's Excess Electrical
Usage, and either Landlord or Tenant shall have the further right to install an
electric current meter, sub-meter or check meter in the Premises (a "Meter") to
measure the amount of electric current consumed in the Premises. The cost of
such Meter special conduits, wiring and panels needed in connection therewith
and the installation, maintenance and repair thereof shall be paid by Tenant.
Tenant shall pay to Landlord, from time to time, but no more frequently than
monthly, for its Excess Electrical Usage at the Premises, plus Landlord's charge
equal to 10% of Tenant's Excess Electrical Usage for Landlord's costs of
maintaining, repairing and reading such Meter. The rate to be paid by Tenant for
submetered electricity shall include any taxes or other charges in connection
therewith.

     Section 14.2   Excess Electricity. Tenant shall at all times comply with
the rules and regulations of the utility company supplying electricity to the
Building. Tenant shall not use any electrical equipment which, in Landlord's
reasonable judgment, would exceed the capacity of the electrical equipment
serving the Premises. If Landlord reasonably determines that Tenant's electrical
requirements necessitate installation of any additional risers, feeders or other
electrical distribution equipment (collectively, "Electrical Equipment"), or if
Tenant provides Landlord with evidence reasonably satisfactory to Landlord of
Tenant's need for excess electricity and requests that additional Electrical
Equipment be installed, Landlord shall, at Tenant's expense, install such
additional Electrical Equipment, provided that Landlord, in its sole judgment,
determines that (a) such installation is practicable and necessary, (b) such
additional Electrical Equipment is permissible under applicable Requirements,
and (c) the installation of such Electrical Equipment will not cause permanent
damage or injury to the Building or the Premises, cause or create a hazardous
condition, entail excessive or unreasonable alterations, interfere with or limit
electrical usage by other tenants or occupants of the Building or exceed the
limits of the switchgear or other facilities serving the Building, or require
power in excess of that available from the utility company serving the Building.
Any costs incurred by Landlord in connection therewith shall be paid by Tenant
within 30 days after the rendition of a bill therefor.

     Section 14.3   Service Disruption. Landlord shall not be liable in any way
to Tenant for any failure, defect or interruption of, or change in the supply,
character and/or quantity of electric service furnished to the Premises for any
reason except if attributable to the gross negligence or willful misconduct of
Landlord, nor shall there be any abatement of Rent or allowance to Tenant for
diminution of rental value, nor shall the same constitute an actual or
constructive eviction of Tenant, in whole or part, or relieve Tenant from any of
its Lease obligations, and no liability shall arise on the

                                       26
<PAGE>

part of Landlord by reason of inconvenience, annoyance or injury to business.
Landlord shall use reasonable efforts to minimize interference with Tenant's use
and occupancy of the Premises as a result of any such failure, defect or
interruption of, or change in the supply, character and/or quantity of, electric
service.

                                  ARTICLE 15

                              ACCESS TO PREMISES

     Section 15.1   Landlord's Access. (a) Landlord, Landlord's agents and
utility service providers servicing the Building may erect, use and maintain
concealed ducts, pipes and conduits in and through the Premises provided such
use does not cause the usable area of the Premises to be reduced beyond a de
minimis amount. Landlord shall promptly repair any damage to the Premises caused
by any work performed pursuant to this Article 15.

          (b)  Landlord, any Lessor or Mortgagee and any other party designated
by Landlord and their respective agents shall have the right to enter the
Premises at all reasonable times, upon reasonable notice (which notice may be
oral) except in the case of emergency, to examine the Premises, to show the
Premises to prospective purchasers, Mortgagees, Lessors or tenants and their
respective agents and representatives or others, to perform Restorative Work to
the Premises or the Building, and Landlord shall be allowed to take all material
into the Premises that may be required for the performance of such Restorative
Work without the same constituting an actual or constructive eviction of Tenant
in whole or in part and without any abatement of Rent; provided, however, that
all such work shall be done as promptly as reasonably possible and so as to
cause as little interference to Tenant as reasonably possible and shall be
subject to the provisions of Section 15.4 below.

          (c)  All parts (except surfaces facing the interior of the Premises)
of all walls, windows and doors bounding the Premises, all balconies, terraces
and roofs adjacent to the Premises, all space in or adjacent to the Premises
used for shafts, stacks, stairways, mail chutes, conduits and other mechanical
facilities, Building Systems; Building facilities and Common Areas are not part
of the Premises, and Landlord shall have the use thereof and access thereto
through the Premises for the purposes of Building operation, maintenance,
alteration and repair.

     Section 15.2   Alterations to Building. Landlord has the right at any time
to (a) change the name, number or designation by which the Building is commonly
known, and (b) alter the Building to change the arrangement or location of
entrances or passageways, doors and doorways, corridors, elevators, stairs,
toilets or other Common Areas without any such acts constituting an actual or
constructive eviction and without incurring any liability to Tenant, so long as
such changes do not materially and adversely affect Tenant's access to the
Premises.

     Section 15.3   Light and Air. If at any time any windows of the Premises
are temporarily darkened or covered over by reason of any Restorative Work, any
of such windows are permanently darkened or covered over due to any Requirement
or there is otherwise a diminution of light, air or view by another structure
which may hereinafter be erected (whether or not by Landlord), Landlord shall
not be liable for any damages and Tenant shall not be entitled to any
compensation or abatement of any Rent, nor shall the same release Tenant from
its obligations hereunder or constitute an actual or constructive eviction.

     Section 15.4   Tenant's Security Requirements. Landlord acknowledges that
Tenant has advised Landlord that Tenant's business at the Premises involves
sensitive information and operations and that Tenant has security requirements
to protect such information and operations. Landlord and any person entering the
Premises with, at the direction of or under the authority of, Landlord shall,
subject to Tenant's compliance with its obligations pursuant to this Section
15.4, follow Tenant's commercially reasonable security requirements, which
include the requirement that all persons entering the Premises be attended by a
representative of Tenant, Tenant shall make a representative available upon 24-
hours prior telephone notice by Landlord. Tenant acknowledges

                                       27
<PAGE>

that to the extent Tenant does not facilitate Landlord's access to the Premises
or certain portions thereof, Landlord shall be absolved from the obligation to
perform any services within such portion of the Premises including cleaning
services. In the event of an emergency that could cause damage to health, safety
or property Landlord shall use good faith efforts to follow Tenant's security
requirements and in such event Landlord will be required to give only such
notice that it in good faith believes is feasible under the circumstances and
need not wait to be accompanied by Tenant or its employees or representatives
(although these parties may still accompany Landlord if they are available and
wish to do so).

                                  ARTICLE 16

                                    DEFAULT

     Section 16.1   Tenant's Defaults. Each of the following events shall be an
"Event of Default" hereunder:

          (a)  Tenant fails to pay when due any installment of Fixed Rent
(including any recurring payments of Tenant's Operating Payment or Tax Payment)
and such default shall continue for 5 Business Days after notice of such default
is given to Tenant, except that if Landlord shall have given one such notice of
default in the payment of Fixed Rent in any 12 month period, Tenant shall not be
entitled to any further notice of its delinquency in the payment of Fixed Rent
or an extended period in which to make payment until such time as 12 consecutive
months shall have elapsed without Tenant having failed to make any such payment
when due, and the occurrence of any default in the payment of Fixed Rent within
such 12 month period after giving one such notice shall constitute an Event of
Default; or

          (b)  Tenant fails to make any other payment of Rent within the period
required by any provision of this Lease and such failure continues for 10 days
following receipt of notice from Landlord;

          (c)  Tenant fails to observe or perform any other term, covenant or
condition of this Lease and such failure continues for more than 30 days (10
days with respect to a default under Article 3) after notice by Landlord to
Tenant of such default, or if such default is of a nature that it cannot be
completely remedied within 30 days, failure by Tenant to commence to remedy such
failure within said 30 days, and thereafter diligently prosecute to completion
all steps necessary to remedy such default, provided in all events the same is
completed within 90 days or as soon thereafter as is commercially practicable
unless Tenant's failure to cure such defaults within such 90 day period would
constitute a default under any Mortgage or Superior Lease; or

          (d)  if Landlord applies or retains any part of the Security Deposit,
and Tenant fails to deposit with Landlord the amount so applied or retained by
Landlord, or to provide Landlord with a replacement Letter of Credit (as
hereinafter defined), if applicable, within 5 days after notice by Landlord to
Tenant stating the amount applied or retained.

     Section 16.2   Landlord's Remedies. (a) Upon the occurrence of an Event of
Default, Landlord, at its option, and without limiting the exercise of any other
right or remedy Landlord may have on account of such Event of Default, and
without any further demand or notice, may give to Tenant 3 days' notice of
termination of this Lease, in which event this Lease and the Term shall come to
an end and expire (whether or not the Term shall have commenced) upon the
expiration of such 3 day period with the same force and effect as if the date
set forth in the notice was the Expiration Date stated herein; and Tenant shall
then quit and surrender the Premises to Landlord, but Tenant shall remain liable
for damages as provided in this Article 16, and/or, to the extent permitted by
law, Landlord may remove all persons and property from the Premises, which
property shall be stored by Landlord at a warehouse or other commercially
reasonable location at the risk, expense and for the account of Tenant.

                                       28
<PAGE>

          (b)  If Landlord elects to terminate this Lease, pursuant to Section
1951.2 of the California Civil Code, Landlord shall be entitled to recover from
Tenant the aggregate of:

               (i)    The worth at the time of award of the unpaid Rent and
charges equivalent to Rent earned as of the date of the termination hereof;

               (ii)   The worth at the time of award of the amount by which the
unpaid Rent and charges equivalent to Rent which would have been earned after
the date of termination hereof until the time of award exceeds the amount of
such rental loss that Tenant proves could have been reasonably avoided;

               (iii)  The worth at the time of award of the amount by which the
unpaid Rent and charges equivalent to Rent for the balance of the Term after the
time of award exceeds the amount of such rental loss that Tenant proves could
have been reasonably avoided;

               (iv)   Any other amount necessary to compensate Landlord for the
detriment proximately caused by Tenant's failure to perform its obligations
under this Lease or which, in the ordinary course of things, would be likely to
result therefrom; and

               (v)    Any other amount which Landlord may hereafter be permitted
to recover from Tenant to compensate Landlord for the detriment caused by
Tenant's default.

For the purposes of this Section 16.2(b), the "time of award" shall mean the
date upon which the judgment in any action brought by Landlord against Tenant by
reason of such Event of Default is entered or such earlier date as the court may
determine; the "worth at the time of award" of the amounts referred to in
Sections 16.2(b)(i) and 16.2(b)(ii) shall be computed by allowing interest on
such amounts at the Interest Rate; and the "worth at the time of award" of the
amount referred to in Section 16.2(b)(iii) shall be computed by discounting such
amount at the discount rate of the Federal Reserve Bank of San Francisco at the
time of award plus one percent per annum.  Tenant agrees that such charges shall
be recoverable by Landlord under California Code of Civil Procedure Section
1174(b) or any similar, successor or related provision of law.

     Section 16.3   Recovering Rent as It Comes Due. Upon any Event of Default,
in addition to any other remedies available to Landlord at law or in equity or
under this Lease, Landlord shall have the remedy described in California Civil
Code Section 1951.4. Accordingly, if Landlord does not elect to terminate this
Lease, Landlord may, from time to time, enforce all of its rights and remedies
under this Lease, including the right to recover all Rent as it becomes due.
Such remedy may be exercised by Landlord without prejudice to its right
thereafter to terminate this Lease in accordance with the other provisions
contained in this Article 16. Landlord's reentry to perform acts of maintenance
or preservation of, or in connection with efforts to relet, the Premises, or any
portion thereof, or the appointment of a receiver upon Landlord's initiative to
protect Landlord's interest under this Lease shall not terminate Tenant's right
to possession of the Premises or any portion thereof and, until Landlord elects
to terminate this Lease, this Lease shall continue in full force and Landlord
may pursue all its remedies hereunder. Nothing in this Article 16 shall be
deemed to affect Landlord's right to indemnification, under the indemnification
clauses contained in this Lease, for Losses arising from events occurring prior
to the termination of this Lease. Landlord covenants and agrees to use its
commercially reasonable efforts to mitigate its damages upon the occurrence of
an Event of Default, provided that in no event shall the foregoing be deemed to
require Landlord to elect any available remedy.

     Section 16.4   Reletting on Tenant's Behalf. To the extent enforceable
under California law, Landlord shall have its remedy as provided in this Section
16.4. If Tenant abandons the Premises or if Landlord elects to reenter or takes
possession of the Premises pursuant to any legal proceeding or pursuant to any
notice provided by Requirements, and until Landlord elects to terminate this
Lease, Landlord may, from time to time, without terminating this Lease, recover
all Rent as it becomes due pursuant to Section 16.3 and/or relet the Premises or
any part thereof for the account of and on behalf of Tenant, on any terms, for
any term (whether or not longer than the Term), and at any

                                       29
<PAGE>

rental as Landlord in its reasonable discretion may deem advisable, and Landlord
may make any Restorative Work to the Premises in connection therewith. Tenant
hereby irrevocably constitutes and appoints Landlord as its attorney-in-fact,
which appointment shall be deemed coupled with an interest and shall be
irrevocable, solely for purposes of reletting the Premises pursuant to the
immediately preceding sentence. If Landlord elects to so relet the Premises on
behalf of Tenant, then rentals received by Landlord from such reletting shall be
applied:

          (a)  First, to reimburse Landlord for the costs and expenses of such
reletting (including costs and expenses of retaking or repossessing the
Premises, removing persons and property therefrom, securing new tenants, and, if
Landlord maintains and operates the Premises, the costs thereof) and necessary
or reasonable Restorative Work.

          (b)  Second, to the payment of any indebtedness of Tenant to Landlord
other than Rent due and unpaid hereunder.

          (c)  Third, to the payment of Rent due and unpaid hereunder, and the
residue, if any, shall be held by Landlord and applied in payment of other or
future obligations of Tenant to Landlord as the same may become due and payable.

     Should the rentals received from such reletting, when applied in the manner
and order indicated above, at any time be less than the total amount owing from
Tenant pursuant to this Lease, then Tenant shall pay such deficiency to
Landlord, and if Tenant does not pay such deficiency within (5) days of delivery
of written notice thereof to Tenant, Landlord may bring an action against Tenant
for recovery of such deficiency or pursue its other remedies hereunder or under
California Civil Code Section 1951.8, California Code of Civil Procedure Section
1161 et seq., or any similar, successor or related Requirements.

     Section 16.5   General. (a) All rights, powers and remedies of Landlord
hereunder and under any other agreement now or hereafter in force between
Landlord and Tenant shall be cumulative and not alternative and shall be in
addition to all rights, powers and remedies given to Landlord at law or in
equity. The exercise of any one or more of such rights or remedies shall not
impair Landlord's right to exercise any other right or remedy including any and
all rights and remedies of Landlord under California Civil Code Section 1951.8,
California Code of Civil Procedure Section 1161 et seq., or any similar,
successor or related Requirements.

          (b)  If, after Tenant's abandonment of the Premises, Tenant leaves
behind any of Tenant's Property, then Landlord shall store such Tenant's
Property at a warehouse or any other commercially reasonable location at the
risk, expense and for the account of Tenant, and such property shall be released
only upon Tenant's payment of such charges, together with moving and other costs
relating thereto and all other sums due and owing under this Lease. If Tenant
does not reclaim such Tenant's Property within the period permitted by law,
Landlord may sell such Tenant's Property in accordance with law and apply the
proceeds of such sale to any sums due and owing hereunder, or retain said
Property, granting Tenant credit against sums due and owing hereunder for the
reasonable value of such Property.

          (c)  To the extent permitted by law, Tenant hereby waives all
provisions of, and protections under, any Requirement to the extent same are
inconsistent and in conflict with specific terms and provisions hereof.

     Section 16.6   Interest. If any payment of Rent is not paid when due,
interest shall accrue on such payment, from the date such payment became due
until paid at the Interest Rate. In addition to interest, if any amount is not
paid when due, within 5 days after same is due, a late charge equal to 5% of
such amount shall be assessed, which late charge Tenant agrees is a reasonable
estimate of the damages Landlord shall suffer as a result of Tenant's late
payment, which damages include Landlord's additional administrative and other
costs associated with such late payment; provided, however, that on 2 occasions
during any calendar year of the Term, Landlord shall give Tenant notice of such
late payment and Tenant shall have a period of 5 days thereafter in which to
make such

                                       30
<PAGE>

payment before any late charge is assessed. The parties agree that it would be
impracticable and difficult to fix Landlord's actual damages in such event. Such
interest and late charges are separate and cumulative and are in addition to and
shall not diminish or represent a substitute for any of Landlord's rights or
remedies under any other provision of this Lease.

     Section 16.7   Other Rights of Landlord. If Tenant fails to pay any
Additional Rent when due, Landlord, in addition to any other right or remedy,
shall have the same rights and remedies as in the case of a default by Tenant in
the payment of Fixed Rent. If Tenant is in arrears in the payment of Rent,
Tenant waives Tenant's right, if any, to designate the items against which any
payments made by Tenant are to be credited, and Landlord may apply any payments
made by Tenant to any items Landlord sees fit, regardless of any request by
Tenant. Landlord reserves the right, without liability to Tenant and without
constituting any claim of constructive eviction, to suspend furnishing or
rendering to Tenant any property, material, labor, utility or other service,
whenever Landlord is obligated to furnish or render the same at the expense of
Tenant, in the event that (but only for so long as) Tenant is in arrears in
paying Landlord for such items for more than 5 days after notice from Landlord
to Tenant demanding the payment of such arrears.

                                  ARTICLE 17

                  LANDLORD'S RIGHT TO CURE; FEES AND EXPENSES

          If Tenant defaults in the performance of its obligations under this
Lease, Landlord, without waiving such default, may perform such obligations at
Tenant's expense: (a) immediately, and without notice, in the case of emergency
or if the default (i) materially interferes with the use by any other tenant of
the Building, (ii) materially interferes with the efficient operation of the
Building, (iii) results in a violation of any Requirement, or (iv) results or
will result in a cancellation of any insurance policy maintained by Landlord,
and (b) in any other case if such default continues after 10 days from the date
Landlord gives notice of Landlord's intention to perform the defaulted
obligation.  All costs and expenses incurred by Landlord in connection with any
such performance by it and all costs and expenses, including reasonable counsel
fees and disbursements, incurred by Landlord in any action or proceeding
(including any unlawful detainer proceeding) brought by Landlord to enforce any
obligation of Tenant under this Lease and/or right of Landlord in or to the
Premises, shall be paid by Tenant to Landlord within 30 days of demand, with
interest thereon at the Interest Rate from the date incurred by Landlord.
Except as expressly provided to the contrary in this Lease, all costs and
expenses which, pursuant to this Lease are incurred by Landlord and payable to
Landlord by Tenant, and all charges, amounts and sums payable to Landlord by
Tenant for any property, material, labor, utility or other services which,
pursuant to this Lease or at the request and for the account of Tenant, are
provided, furnished or rendered by Landlord, shall become due and payable by
Tenant to Landlord in accordance with the terms of the bills rendered by
Landlord to Tenant.

                                  ARTICLE 18

              NO REPRESENTATIONS BY LANDLORD; LANDLORD'S APPROVAL

     Section 18.1   No Representations. Except as expressly set forth herein,
Landlord and Landlord's agents have made no warranties, representations,
statements or promises with respect to the Building, the Real Property or the
Premises and no rights, easements or licenses are acquired by Tenant by
implication or otherwise. 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.

     Section 18.2   No Money Damages. Wherever in this Lease Landlord's consent
or approval is required, if Landlord refuses to grant such consent or approval,
whether or not Landlord expressly agreed that such consent or approval would not
be unreasonably withheld, Tenant shall not make, and Tenant hereby waives, any
claim for money damages (including any claim by way of set-off,

                                       31
<PAGE>

counterclaim or defense) based upon Tenant's claim or assertion that Landlord
unreasonably withheld or delayed its consent or approval. Tenant's sole remedy
shall be an action or proceeding to enforce such provision, by specific
performance, injunction or declaratory judgment. In no event shall Landlord be
liable for, and Tenant, on behalf of itself and all other Tenant Parties, hereby
waives any claim for, any indirect, consequential or punitive damages, including
loss or profits or business opportunity, arising under or in connection with
this Lease, even if due to the gross negligence or willful misconduct of
Landlord or its agents or employees.

     Section 18.3   Reasonable Efforts. For purposes of this Lease, "reasonable
efforts" by Landlord shall not include an obligation to employ contractors or
labor at overtime or other premium pay rates or to incur any other overtime
costs or additional expenses whatsoever.

                                  ARTICLE 19

                                  END OF TERM

     Section 19.1   Expiration. Upon the expiration or other termination of this
Lease, Tenant shall quit and surrender the Premises to Landlord vacant, broom
clean and in good order and condition, ordinary wear and tear and damage for
which Tenant is not responsible under the terms of this Lease excepted, and
Tenant shall remove all of Tenant's Property and Tenant's Alterations (exclusive
of the Improvements described on Exhibit C) as may be required pursuant to
Article 5.

     Section 19.2   Holdover Rent. Landlord and Tenant recognize that Landlord's
damages resulting from Tenant's failure to timely surrender possession of the
Premises may be substantial, may exceed the amount of the Rent payable
hereunder, and will be impossible to accurately measure. Accordingly, if
possession of the Premises is not surrendered to Landlord on the Expiration Date
or sooner termination of this Lease, in addition to any other rights or remedies
Landlord may have hereunder or at law, Tenant shall (a) pay to Landlord for each
month (or any portion thereof) during which Tenant holds over in the Premises
after the Expiration Date or sooner termination of this Lease, a sum equal to
150% of the Rent payable under this Lease for the last full calendar month of
the Term, (b) be liable to Landlord for (i) any payment or rent concession which
Landlord may be required to make to any third-party tenant not affiliated with
Landlord which is obtained by Landlord for all or any part of the Premises (a
"New Tenant") in order to induce such New Tenant not to terminate its lease by
reason of the holding-over by Tenant, and (ii) the loss of the benefit of the
bargain if any New Tenant shall terminate its lease by reason of the holding-
over by Tenant, and (c) if any such nonconsensual holding over continues for
more than 30 days, indemnify Landlord against all claims for actual damages (but
in no event any consequential damages) by any New Tenant. No holding-over by
Tenant, nor the payment to Landlord of the amounts specified above, shall
operate to extend the Term hereof. Nothing herein contained shall be deemed to
permit Tenant to retain possession of the Premises after the Expiration Date or
sooner termination of this Lease, and no acceptance by Landlord of payments from
Tenant after the Expiration Date or sooner termination of this Lease shall be
deemed to be other than on account of the amount to be paid by Tenant in
accordance with the provisions of this Section 19.2.

                                  ARTICLE 20

                                QUIET ENJOYMENT

          Provided this Lease is in full force and effect and no Event of
Default then exists, Tenant (and any person lawfully claiming through and under
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 and to all Superior Leases and Mortgages.

                                       32
<PAGE>

                                  ARTICLE 21

                            NO SURRENDER; NO WAIVER

     Section 21.1   No Surrender or Release. No act or thing done by Landlord or
Landlord's agents or employees during the Term shall be deemed an acceptance of
a surrender of the Premises, and no provision of this Lease shall be deemed to
have been waived by Landlord, unless such waiver is in writing and is signed by
Landlord.

     Section 21.2   No Waiver. The failure of either party 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 be
construed as a waiver or relinquishment for the future performance of such
obligations of this Lease or the Rules and Regulations, or of the right to
exercise such election but the same shall continue and remain in full force and
effect with respect to any subsequent breach, act or omission. The receipt by
Landlord of any Rent payable pursuant to this Lease or any other sums with
knowledge of the breach of any covenant of this Lease shall not be deemed a
waiver of such breach. No payment by Tenant or receipt by Landlord of a lesser
amount than the monthly Rent herein stipulated shall be deemed to be other than
a payment on account of the earliest stipulated Rent, or as Landlord may elect
to apply such payment, nor shall any endorsement or statement on any check or
any letter accompanying any check or payment as 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 Rent or pursue any other remedy
provided in this Lease.

                                  ARTICLE 22

                     WAIVER OF TRIAL BY JURY, COUNTERCLAIM

     Section 22.1   Jury Trial Waiver. THE PARTIES HEREBY AGREE THAT THIS LEASE
CONSTITUTES A WRITTEN CONSENT TO WAIVER OF TRIAL BY JURY PURSUANT TO THE
PROVISIONS OF CALIFORNIA CODE OF CIVIL PROCEDURE SECTION 631 AND EACH PARTY DOES
HEREBY CONSTITUTE AND APPOINT THE OTHER PARTY ITS TRUE AND LAWFUL ATTORNEY-IN-
FACT, WHICH APPOINTMENT IS COUPLED WITH AN INTEREST, AND EACH PARTY DOES HEREBY
AUTHORIZE AND EMPOWER THE OTHER PARTY, IN THE NAME, PLACE AND STEAD OF SUCH
PARTY, TO FILE THIS LEASE WITH THE CLERK OR JUDGE OF ANY COURT OF COMPETENT
JURISDICTION AS A STATUTORY WRITTEN CONSENT TO WAIVER OF TRIAL BY JURY.

          LANDLORD'S INITIALS: _____      TENANT'S INITIALS: _____

     Section 22.2   Waiver of Counterclaim. If Landlord commences any summary
proceeding against Tenant, Tenant will not interpose any counterclaim of any
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 23

                                    NOTICES

          Except as otherwise expressly provided in this Lease, all consents,
notices, demands, requests, approvals or other communications given under this
Lease shall be in writing and shall be deemed sufficiently given or rendered if
delivered by hand (provided a signed receipt is obtained) or if sent by
registered or certified mail (return receipt requested) or by a nationally
recognized overnight delivery service making receipted deliveries, addressed to
Landlord and Tenant as set forth in

                                       33
<PAGE>

Article 1, and to any Mortgagee or Lessee who shall require copies of notices
and whose address is provided to Tenant, or to such other address(es) as
Landlord, Tenant or any Mortgagee or Lessor may designate as its new address(es)
for such purpose by notice given to the other in accordance with the provisions
of this Article 23. Any such approval, consent, notice, demand, request or other
communication shall be deemed to have been given on the date of receipted
delivery, refusal to accept delivery or when delivery is first attempted but
cannot be made due to a change of address for which no notice is given or 3
Business Days after it shall have been mailed as provided in this Article 23,
whichever is earlier.

                                  ARTICLE 24

                             RULES AND REGULATIONS

          All Tenant Parties shall observe and comply with the Rules and
Regulations, as supplemented or amended from time to time. Landlord reserves the
right, from time to time, to adopt additional Rules and Regulations and to amend
the Rules and Regulations then in effect.  Nothing contained in this Lease shall
impose upon Landlord any obligation to enforce the Rules and Regulations or
terms, covenants or conditions in any other lease against any other Building
tenant, and Landlord shall not be liable to Tenant for violation of the same by
any other tenant, its employees, agents, visitors or licensees, provided that
Landlord shall enforce the Rules or Regulations against Tenant in a non-
discriminatory fashion.

                                  ARTICLE 25

                                    BROKER

          Landlord has retained Landlord's Agent as leasing agent in connection
with this Lease and Landlord will be solely responsible for any fee that may be
payable to Landlord's Agent.  Landlord agrees to pay a commission to Cushman
Realty Corporation pursuant to a separate agreement.  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 Landlord's Agent and Tenant's
Broker and that no other broker, finder or like entity procured or negotiated
this Lease or is entitled to any fee or commission in connection herewith.  Each
of Landlord and Tenant shall indemnify, defend, protect and hold the other party
harmless from and against any and all Losses which the indemnified party may
incur by reason of any claim of or liability to any broker, finder or like agent
(other than Landlord's Agent and Tenant's Broker) arising out of any dealings
claimed to have occurred between the indemnifying party and the claimant in
connection with this Lease, and/or the above representation being false.

                                  ARTICLE 26

                                   INDEMNITY

     Section 26.1   Tenant's Indemnity. Tenant shall not do or permit to be done
any act or thing upon the Premises or the Building 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 any Requirement (the responsibility
for which Requirement is Tenant's under this Lease), and shall exercise such
control over the Premises as to fully protect Landlord against any such
liability. Tenant shall indemnify, defend, protect and hold harmless each of the
Indemnitees from and against any and all Losses, resulting from any claims (i)
against the Indemnitees arising from any act, omission or negligence of all
Tenant Parties, (ii) against the Indemnitees, to the extent arising from any
accident, injury or damage whatsoever caused to any person or to the property of
any person and occurring in or about the Premises, except to the extent caused
by the gross negligence or willful misconduct of the Indemnitees, and (iii)
against the Indemnitees resulting from any breach, violation or

                                       34
<PAGE>

nonperformance of any covenant, condition or agreement of this Lease on the part
of Tenant to be fulfilled, kept, observed or performed.

     Section 26.2   Landlord's Indemnity. Landlord shall indemnify, defend and
hold harmless Tenant from and against all Losses incurred by Tenant arising from
any accident, injury or damage whatsoever caused to any person or the property
of any person in or about the Common Areas and, with respect to claims for
personal injury, the Premises, to the extent attributable to the gross
negligence or willful misconduct of Landlord or its employees or agents.

     Section 26.3   Defense and Settlement. If any claim, action or proceeding
is made or brought against any Indemnitee, then upon demand by an Indemnitee,
Tenant, at its sole cost and expense, shall resist or defend such claim, action
or proceeding in the Indemnitee's name (if necessary), by attorneys approved by
the Indemnitee, which approval shall not be unreasonably withheld (attorneys for
Tenant's insurer shall be deemed approved for purposes of this Section 26.3).
Notwithstanding the foregoing, an Indemnitee may retain its own attorneys to
participate or assist in defending any claim, action or proceeding involving
potential liability in excess of the amount available under Tenant's liability
insurance carried under Section 11.1 for such claim and Tenant shall pay the
reasonable fees and disbursements of such attorneys. If Tenant fails to
diligently defend or if there is a conflict, then Landlord may retain separate
counsel at Tenant's expense. Notwithstanding anything herein contained to the
contrary, Tenant may direct the Indemnitee to settle any claim, suit or other
proceeding provided that (a) such settlement shall involve no obligation on the
part of the Indemnitee other than the payment of money, (b) any payments to be
made pursuant to such settlement shall be paid in full exclusively by Tenant at
the time such settlement is reached, (c) such settlement shall not require the
Indemnitee to admit any liability, and (d) the Indemnitee shall have received an
unconditional release from the other parties to such claim, suit or other
proceeding.

                                  ARTICLE 27

                                 MISCELLANEOUS

     Section 27.1   Delivery. This Lease shall not be binding upon Landlord or
Tenant unless and until both Landlord and Tenant shall have executed and
delivered a fully executed copy of this Lease to each other.

     Section 27.2   Transfer of Real Property. Landlord's obligations under this
Lease shall not be binding upon the Landlord named herein after the sale,
conveyance, assignment or transfer (collectively, a "Transfer") by such Landlord
(or upon any subsequent landlord after the Transfer by such subsequent landlord)
of its interest in the Building or the Real Property, as the case may be, and in
the event of any such Transfer, Landlord (and any such subsequent Landlord)
shall be entirely freed and relieved of all covenants and obligations of
Landlord hereunder arising from and after the date of Transfer, and the
transferee of Landlord's interest (or that of such subsequent Landlord) in the
Building or the Real Property, as the case may be, shall be deemed to have
assumed all obligations under this Lease arising from and after the date of
Transfer.

     Section 27.3   Limitation on Liability. The liability of Landlord for
Landlord's obligations under this Lease shall be limited to Landlord's interest
in the Real Property and Tenant shall not look to any other property or assets
of Landlord or the property or assets of any direct or indirect partner, member,
manager, shareholder, director, officer, principal, employee or agent of
Landlord (collectively, the "Parties") in seeking either to enforce Landlord's
obligations under this Lease or to satisfy a judgment for Landlord's failure to
perform such obligations; and none of the Parties shall be personally liable for
the performance of Landlord's obligations under this Lease.

     Section 27.4   Rent. All amounts payable by Tenant to or on behalf of
Landlord under this Lease, whether or not expressly denominated Fixed Rent,
Tenant's Tax Payment, Tenant's Operating Payment, Additional Rent or Rent, shall
constitute rent for the purposes of Section 502(b)(6) of the United States
Bankruptcy Code.

                                       35
<PAGE>

     Section 27.5   Entire Document. This Lease (including any Schedules and
Exhibits referred to herein and all supplementary agreements provided for
herein) contains the entire agreement between the parties and all prior
negotiations and agreements are merged into this Lease. All of the Schedules and
Exhibits attached hereto are incorporated in and made a part of this Lease,
provided that in the event of any inconsistency between the terms and provisions
of this Lease and the terms and provisions of the Schedules and Exhibits hereto,
the terms and provisions of this Lease shall control.

     Section 27.6   Governing Law. This Lease shall be governed in all respects
by the laws of the State of California.

     Section 27.7   Unenforceability. If any provision of this Lease, or its
application 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 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 provision hereof shall remain valid and enforceable
to the fullest extent permitted by law.

     Section 27.8   Lease Disputes. (a) 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 state courts of
the State of California or the United States District Court for the Northern
District of California and for that purpose hereby expressly and irrevocably
submits itself to the jurisdiction of such courts. Tenant agrees that so far as
is permitted under applicable law, this consent to personal jurisdiction shall
be self-operative and no further instrument or action, other than service of
process in one of the manners specified in this Lease, or as otherwise permitted
by law, shall be necessary in order to confer jurisdiction upon it in any such
court.

          (b)  To the extent that Tenant has or hereafter may acquire any
immunity from jurisdiction of any court or from any legal process (whether
through service or notice, attachment prior to judgment, attachment in aid of
execution, execution or otherwise) with respect to itself or its property,
Tenant irrevocably waives such immunity in respect of its obligations under this
Lease.

     Section 27.9   Landlord's Agent. Unless Landlord delivers written notice to
Tenant to the contrary, Landlord's Agent is authorized to act as Landlord's
agent in connection with the performance of this Lease, and Tenant shall direct
all correspondence and requests to, and shall be entitled to rely upon
correspondence received from Landlord's Agent. Tenant acknowledges that
Landlord's Agent is acting solely as agent for Landlord in connection with the
foregoing; and neither Landlord's Agent nor any of its direct or indirect
partners, members, managers, officers, shareholders, directors, employees,
principals, agents or representatives shall have any liability to Tenant in
connection with the performance of this Lease, and Tenant waives any and all
claims against any and all of such parties arising out of, or in any way
connected with, this Lease, the Building or the Real Property.

     Section 27.10  Estoppel. (a) Within 7 Business Days following request from
Landlord, any Mortgagee or any Lessor, Tenant shall deliver to Landlord a
statement executed and acknowledged by Tenant, in form reasonably satisfactory
to Landlord, (a) stating the Commencement Date, the Rent Commencement Date and
the Expiration Date, and that this Lease is then in full force and effect and
has not been modified (or if modified, setting forth all modifications), (b)
setting forth the date to which the Fixed Rent and any Additional Rent have been
paid, together with the amount of monthly Fixed Rent and Additional, Rent then
payable, (c) stating whether or not, to the best of Tenant's knowledge, Landlord
is in default under this Lease, and, if Landlord is in default, setting forth
the specific nature of all such defaults, (d) stating the amount of the Security
Deposit, if any, under this Lease, (e) stating whether there are any subleases
or assignments affecting the Premises, (f) stating the address of Tenant to
which all notices and communications under the Lease shall be sent, and (g)
responding to any other matters reasonably requested by Landlord, such Mortgagee
or such Lessor. Tenant acknowledges that any statement delivered pursuant to
this Section 27.10 may be relied upon by any purchaser or owner of the Real
Property or the Building, or all or any portion of Landlord's interest in

                                       36
<PAGE>

the Real Property or the Building or any Superior Lease, or by any Mortgagee, or
assignee thereof or by any Lessor, or assignee thereof.

          (b)  Landlord shall, within 7 Business Days after Tenant's request,
execute and deliver to Tenant an estoppel certificate in favor of Tenant and
such other persons as Tenant shall request, setting forth the following: (a) a
ratification of this Lease; (b) the Commencement Date and Expiration Date; (c)
that this Lease is in full force and effect and has not been assigned, modified,
supplemented or amended (except by such writing as shall be stated); (d) that
all conditions under this Lease to be performed by Tenant have, to Landlord's
knowledge, been satisfied, or, in the alternative, those claimed by Landlord to
be unsatisfied; (e) that, to Landlord's knowledge, no defenses or offsets exist
against the enforcement of this Lease by Landlord, or in the alternative, those
claimed by Landlord; (f) that the amount of advance rent, if any (or none if
such is the case), has been paid by Tenant; (g) the date to which Fixed Rent has
been paid; (h) the amount of the Security Deposit (if any); and (i) such other
information as Tenant may reasonably request.

     Section 27.11  Certain Interpretational Rules. For purposes of this Lease,
whenever the words "include", "includes", or "including" are used, they shall be
deemed to be followed by the words "without limitation" and, whenever the
circumstances or the context requires, the singular shall be construed as the
plural, the masculine shall be construed as the feminine and/or the neuter and
vice versa. This Lease shall be interpreted and enforced without the aid of any
canon, custom or rule of law requiring or suggesting construction against the
party drafting or causing the drafting of the provision in question. The
captions in this Lease are inserted only as a matter of convenience and for
reference and in no way define, limit or describe the scope of this Lease or the
intent of any provision hereof.

     Section 27.12  Parties Bound. The terms, covenants, conditions and
agreements contained in this Lease shall bind and inure to the benefit of
Landlord and Tenant and, except as otherwise provided in this Lease, to their
respective legal representatives, successors, and assigns.

     Section 27.13  Memorandum of Lease. This Lease shall not be recorded;
however, at Landlord's request, Landlord and Tenant shall promptly execute,
acknowledge and deliver a memorandum with respect to this Lease sufficient for
recording and Landlord may record the Memorandum.

     Section 27.14  Counterparts. This Lease may be executed in 2 or more
counterparts, each of which shall constitute an original, but all of which, when
taken together, shall constitute but one instrument.

     Section 27.15  Survival. All obligations and liabilities of Landlord or
Tenant to the other which accrued before the expiration or other termination of
this Lease, and all such obligations and liabilities which by their nature or
under the circumstances can only be, or by the provisions of this Lease may be,
performed after such expiration or other termination, shall survive the
expiration or other termination of this Lease. Within 90 days following the
Expiration Date or earlier termination of this Lease and the vacation of the
Premises by Tenant, Landlord shall advise Tenant of the existence of any claims
by Landlord that Tenant's surrender of the Premises was not in accordance with
Section 19.1. Without limiting the generality of the foregoing, the rights and
obligations of the parties with respect to any indemnity under this Lease, and
with respect to any Rent and any other amounts payable under this Lease, shall
survive the expiration or other termination of this Lease, provided that
Tenant's obligation for any Rent shall end on the 3rd anniversary of the
Expiration Date or earlier termination of this Lease (unless such claims are
then the subject of any lawsuit or other proceeding filed by Landlord prior to
the expiration of such 3-year period). If Landlord reasonably determines that a
claim against Tenant exists, Landlord shall promptly advise Tenant of the same.

     Section 27.16  Code Waivers. Tenant hereby waives any and all rights under
and benefits of Subsection 1 of Section 1931, 1932, Subdivision 2, 1933,
Subdivision 4, 1941 and 1942 of the California Civil Code, Section 1265.130 of
the California Code of Civil Procedure (allowing either party to petition a
court to terminate a lease in the event of a partial taking), and Section
1174(c) of the

                                       37
<PAGE>

California Code of Civil Procedure and Section 1951.7 of the California Civil
Code (providing for Tenant's right to satisfy a judgment in order to prevent a
forfeiture of this Lease or requiring Landlord to deliver written notice to
Tenant of any reletting of the Premises), and any similar law, statute or
ordinance now or hereinafter in effect.

     Section 27.17  Rooftop Communications Equipment. During the Term of this
Lease, Tenant shall have the right, upon payment of a fee in the amount of
$500.00 per month (the "Roof Fee") to install and operate one microwave
transmitter-receivers, satellite dish or antenna (the "Satellite Dish") of a
weight, height and width reasonably acceptable to Landlord and as reasonably
necessary for Tenant's use of the Premises and conduct of its business therein.
The Roof Fee shall be payable to Landlord concurrently with Tenant's payment of
Fixed Rent commencing as of the month Tenant first installs such Satellite Dish.
Tenant's rights pursuant to this Section 27.17 may not be assigned independent
of this Lease or sublet other than to a subtenant in occupancy of, and
conducting business operations within, at least one floor of the Premises and
are subject to the following:

          (a)  The precise location of the Satellite Dish shall be as approved
by Landlord in its reasonable discretion within ten (10) days following receipt
of Tenant's request to install such Satellite Dish on the roof of the Building.

          (b)  Tenant shall pay any federal, state and local taxes applicable to
the installation and use of the Satellite Dish and Tenant shall procure,
maintain and pay for and obtain all fees, permits and governmental agency
licenses necessary in connection with the installation, maintenance and
operation of such Satellite Dish; provided, however, that Landlord shall
reasonably cooperate with the efforts of Tenant in connection with any
governmental application or filing required thereby.

          (c)  Tenant shall be permitted, at its expense, but without separate
charge other than any charges permitted to be imposed by Landlord under Article
5 hereof, to install, modify, alter, repair, maintain, operate and replace in
one existing chaseway of the Building in an area in the core of the Building one
non-dedicated one-inch conduit for its cabling use (and the use of the cables
contained therein connecting to the Building's roof for operation of Tenant's
Satellite Dish). All installations required in connection with the Satellite
Dish shall be made by means of conduits, wires or cables that will pass through
existing openings in the walls or roof decks of the Building, and all cables and
wires located on the roof of the Building used in connection with the Satellite
Dish shall be covered by rust-proof conduits and attachments. In no event shall
any of Tenant's installations be made through the roof surface or membrane of
the Building without the prior written consent of Landlord, which consent may be
withheld in Landlord's sole and absolute discretion, exercised in good faith.
The installation of the Satellite Dish shall be subject to Landlord's review and
approval and shall conform to the engineering standards commonly used for
installing similar microwave and satellite dishes on comparable buildings.

          (d)  Tenant, at its sole cost and expense, shall comply with all
present and future laws and with any reasonable requirements of any applicable
fire rating bureau relating to the maintenance, use, installation and operation
of the Satellite Dish. Tenant shall install, maintain and operate all of its
equipment used in connection with the Satellite Dish in conformity with all laws
and all regulations of all government agencies having jurisdiction over the
installation, use and operation of such Satellite Dish, including, without
limitation, the Federal Aviation Administration and the Federal Communications
Commission; provided, however, that if compliance with such laws or regulations
would require a change in the size, configuration or location of the Satellite
Dish, such changes shall be subject to Landlord's prior written consent in
accordance with subsection (a) above.

          (e)  Within 5 Business Days after the expiration or earlier
termination of the Term of this Lease, Tenant shall remove the Satellite Dish
and all wires and cables used in connection with such Satellite Dish, and shall
restore and repair all damage to the Building occasioned by the installation,
maintenance or removal of such Satellite Dish. If Tenant fails to timely
complete such removal, restoration and repair, all sums incurred by Landlord to
complete such work shall be paid by Tenant to Landlord within 10 Days of demand.

                                       38
<PAGE>

          (f)  Landlord makes no representations or warranties whatsoever with
respect to the fitness or suitability of the Building for the installation,
maintenance and operation of the Satellite Dish, including, without limitation,
with respect to the quality and clarity of any receptions and transmissions to
or from the Satellite Dish and the presence of any interference with such
signals, whether emanating from the Building or otherwise.

          (g)  Tenant must contact the manager of the Building prior to the date
Tenant proposes to install the Satellite Dish on the roof of the Building in
order to make arrangements for the movement of any materials needed in
connection with the installation of such Satellite Dish.

          (h)  Tenant shall provide adequate maintenance personnel in order to
ensure the safe operation of the Satellite Dish. In addition, Tenant shall
install, maintain and operate all of its equipment used in connection with the
Satellite Dish in a fashion and manner so as not to interfere with the use and
operation of any: (i) other television or radio equipment in the Building; (ii)
present or future electronic control system for any of the Building Systems or
the operation of the elevators in the Building; (iii) other transmitting,
receiving or master television, telecommunications or microwave antenna
equipment currently located on the roof of the Building; or (iv) any radio
communication system now used by Landlord. In addition, Tenant shall use its
commercially reasonable efforts to ensure that Tenant will not interfere with
any equipment installed by Landlord in the future. Landlord shall use its
commercially reasonable efforts to ensure that Tenant's equipment will not be
unreasonably interfered with.

     Section 27.18  Inability to Perform. This Lease (and the obligation of the
parties hereunder (including the obligation of Tenant to pay Rent and to perform
all of the other covenants and agreements of Tenant hereunder) shall not be
affected, impaired or excused by any Unavoidable Delays, except as otherwise
expressly set forth herein. Each party shall use reasonable efforts to promptly
notify the other of any Unavoidable Delay which prevents such party from
fulfilling any of its obligations under this Lease. Notwithstanding the
foregoing, no Unavoidable Delay shall excuse the timely performance of any
obligation under this Lease which is to be performed or discharged by the
payment of money.

                                  ARTICLE 28

                               SECURITY DEPOSIT

     Section 28.1   Security Deposit. Tenant shall deposit the Security Deposit
with Landlord upon the execution of this Lease in cash as security for the
faithful performance and observance by Tenant of the terms, covenants and
conditions of this Lease.

     Section 28.2   Letter of Credit. In lieu of a cash Security Deposit, Tenant
may deliver the Security Deposit to Landlord in the form of a clean,
irrevocable, non-documentary and unconditional letter of credit (the "Letter of
Credit") issued by and drawable upon any commercial bank which is a member of
the New York Clearing House Association or other bank satisfactory to Landlord,
trust company, national banking association or savings and loan association (the
"Issuing Bank"), which has outstanding unsecured, uninsured and unguaranteed
indebtedness, or shall have issued a letter of credit or other credit facility
that constitutes the primary security for any outstanding indebtedness (which is
otherwise uninsured and unguaranteed), that is then rated, without regard to
qualification of such rating by symbols such as "+" or "-" or numerical
notation, "Aa" or better by Moody's Investors Service and "AA" or better by
Standard & Poor's Rating Service, and has combined capital, surplus and
undivided profits of not less than $500,000,000.00. Landlord hereby approves
BankBoston or Fleet Bank as the issuer of the Letters of Credit and the form of
Letter of Credit attached hereto as Exhibit G. Such Letter of Credit shall (a)
name Landlord as beneficiary, (b) be in the amount of the Security Deposit, (c)
have a term of not less than one year, (d) permit multiple drawings, (e) be
fully transferable by Landlord without the payment of any fees or charges by
Landlord, and (f) otherwise be in form and content reasonably satisfactory to
Landlord. If upon any transfer of the Letter of Credit,

                                       39
<PAGE>

any fees or charges shall be so imposed, then such fees or charges shall be
payable solely by Tenant. The Letter of Credit shall provide that it shall be
deemed automatically renewed, without amendment, for consecutive periods of one
year each thereafter during the Term (and in no event shall the Letter of Credit
expire prior to the 30th day following the Expiration Date) unless the Issuing
Bank sends a notice (the "Non-Renewal Notice") to Landlord by certified mail,
return receipt requested, not less than 30 days next preceding the then
expiration date of the Letter of Credit stating that the Issuing Bank has
elected not to renew the Letter of Credit. Landlord shall have the right, upon
receipt of the Non-Renewal Notice, to draw the full amount of the Letter of
Credit, by sight draft on the Issuing Bank, and shall thereafter hold or apply
the cash proceeds of the Letter of Credit pursuant to the terms of this Article
28, until Tenant delivers to Landlord a substitute Letter of Credit which meets
the requirements of this Section 28.2. The Issuing Bank shall agree with all
drawers, endorsers and bona fide holders that drafts drawn under and in
compliance with the terms of the Letter of Credit will be duly honored upon
presentation to the Issuing Bank (in person, by courier or otherwise provided in
the attached approved form of Letter of Credit) at an office location in San
Francisco, California, Boston, Massachusetts or the location of BankBoston's or
Fleet Bank's letter of credit department. The Letter of Credit shall be subject
in all respects to the Uniform Customs and Practice for Documentary Credits
(1993 revision), International Chamber of Commerce Publication No. 500.

     Section 28.3   Application of Security. If (a) an Event of Default by
Tenant occurs in the payment or performance of any of the terms, covenants or
conditions of this Lease, including the payment of Rent, Landlord may apply or
retain the whole or any part of the cash Security Deposit necessary for the
curing of the Event of Default or may notify the Issuing Bank and thereupon
receive all or a portion of the Security Deposit represented by the Letter of
Credit and use, apply, or retain the whole or any part of such proceeds, as the
case may be, to the extent required for the payment of any Fixed Rent or any
other sum as to which Tenant is in default including (i) any sum which Landlord
may reasonably expend or may be required to expend by reason of Tenant's
default, and/or (i) any damages to which Landlord is entitled pursuant to this
Lease, whether such damages accrue before or after summary proceedings or other
reentry by Landlord. If Landlord applies or retains any part of the Security
Deposit, Tenant, within 10 Days of demand, shall deposit with Landlord the
amount so applied or retained so that Landlord shall have the full Security
Deposit on hand at all times during the Term. If Tenant shall fully and
faithfully comply with all of the terms, covenants and conditions of this Lease,
the Security Deposit shall be returned to Tenant within 30 days after the
Expiration Date and after delivery of possession of the Premises to Landlord in
the manner required by this Lease.

     Section 28.4   Transfer. Upon a sale or other transfer of the Real Property
or the Building, or any financing of Landlord's interest therein, Landlord shall
have the right to transfer the Security Deposit to its transferee or lender.
With respect to the Letter of Credit, within 10 days after notice of such
transfer or financing, Tenant, at its sole cost, shall arrange for the transfer
of the Letter of Credit to the new landlord or the lender, as designated by
Landlord in the foregoing notice or have the Letter of Credit reissued in the
name of the new landlord or the lender. Upon such Transfer Tenant shall look
solely to the new landlord or lender for the return of such cash Security
Deposit or Letter of Credit and the provisions hereof shall apply to every
transfer or assignment made of the Security Deposit to a new landlord. Tenant
shall not assign or encumber or attempt to assign or encumber the cash Security
Deposit or Letter of Credit and neither Landlord nor its successors or assigns
shall be bound by any such action or attempted assignment, or encumbrance.

                                  ARTICLE 29

                                    PARKING

          Located in the lower level of 555 Market is the parking garage serving
the Project (the "Garage").  Except as otherwise provided below, the Garage is
open 24 hours a day, 7 days a week to tenants and their Building employees
holding valid Building/Garage passes.  Subject to such access

                                       40
<PAGE>

control systems as Landlord may from time to time reasonably establish (which
system may ultimately be based upon a card key system integrated with the
Building's access control system), the Garage allows monthly parking with
unlimited 24 hours access. During the Term of this Lease and subject to
Unavoidable Delays and other causes beyond Landlord's reasonable control,
including any limitations on the grant of monthly parking rights imposed by the
City and County of San Francisco, Landlord shall make available or cause to be
available to Tenant through-out the Term during the hours of operation set forth
above, 2 parking privileges which shall be on a must-take must-pay basis;
provided, however, that Tenant, upon not less than 30 days notice to Landlord,
may reduce the number of parking privileges provided that once so reduced by
Tenant, Tenant shall have no right to later increase such number of privileges.
For each parking privilege made available to Tenant, Tenant shall pay monthly in
advance to the operator of the parking garage, on or before the 25/th/ day of
the preceding calendar month, a parking charge in an amount which is currently
equal to $375.00 per month per car and is subject to periodic change in
accordance with Landlord's publicly announced monthly parking charge.

          Tenant shall at all times comply with (and the provisions hereof shall
be expressly subject to) all applicable Requirements regarding the use of the
Garage.  Landlord reserves the right to adopt, modify and enforce reasonable
rules (the "Garage Rules") governing the use of the Garage from time to time,
including any key card, sticker or other identification or entrance system.
Landlord may refuse to permit any person who violates any such Garage Rules to
park in the Garage, and any violation of the Rules shall subject the car to
removal, at such person's expense from the Garage.  The use of all parking
privileges shall be solely for use by Tenant's employees (or the employees of a
permitted subtenant) working in the Building.

          The parking privileges hereunder may be provided on an unreserved
valet parking basis.  Tenant acknowledges that Landlord has arranged for the
Garage to be operated by an independent contractor.  Accordingly, Tenant
acknowledges that Landlord shall have no liability for claims arising through
acts or omissions of such independent contractor except to the extent due to
Landlord's negligence or willful misconduct.  Except when caused by the gross
negligence, willful misconduct or criminal acts of Landlord or Landlord's Agent
or their respective employees, agents or contractors, Landlord shall have no
liability whatsoever for any damage to property or any other items located in
the Garage, nor for any personal injuries or death arising out of any matter
relating to the Garage, and in all events, Tenant agrees to look first to its
insurance carrier for payment of any losses sustained in connection with any use
of the Garage and secondly to the operator of the Garage.  Landlord reserves the
right to assign specific spaces, and to reserve spaces for visitors, small cars,
handicapped persons and for other tenants, guests of tenants or other parties,
and Tenant shall not park in any such assigned or reserved spaces.  If Landlord
utilizes a card-key access system, Landlord's charge for any replacement cards
shall be reasonable.  Landlord also reserves the right to close all or any
portion of the Garage in order to make repairs or perform maintenance services,
or to alter, modify, re-stripe or renovate the Garage, or if required by
casualty, condemnation, or Unavoidable Delay.  In such event, Landlord shall
refund any prepaid parking rent hereunder, prorated on a per diem basis and
shall use its reasonable efforts to complete such maintenance or repair as soon
as reasonably possible.

                                       41
<PAGE>

          Tenant agrees to acquaint all persons to whom Tenant assigns parking
privilege of any Garage Rules promulgated by Landlord with respect to the Garage
and the parking privileges granted to Tenant herein.

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

LANDLORD:                                    TENANT:

TST 555/575 MARKET, L.L.C.,                  CMGI, INC.,
a Delaware limited liability company         a Delaware corporation

By:  /s/ Andrew J. Nathan                    By:  /s/ Andrew J. Hajducky, III

Its: Vice President                          Its: Executive Vice President,
                                                  CFO and Treasurer

                                       42
<PAGE>

                                  EXHIBIT A-1

                       (Floor Plan of the 12/th/ Floor)

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

                                  EXHIBIT A-2

                       (Floor Plan of the 13/th/ Floor)

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

                                   EXHIBIT B

                                  Definitions

          Above Building Standard Installations:  Any Alterations or
improvements to the Premises, including all Specialty Alterations, which exceed
Building Standard Installations.

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

          Building Systems:  The mechanical, electrical, plumbing, sanitary,
sprinkler, heating, ventilation and air conditioning, security, life-safety,
elevator and other service systems or facilities of the Building in place at the
Premises as of the Effective Date (excluding, however, supplemental HVAC systems
of Tenant and any modifications to the Building Systems made by or for Tenant
after the Effective Date).

          Business Days:  All days, excluding Saturdays, Sundays and all days
observed by either the State in which the Building is located, the Federal
Government or the labor unions servicing the Building as legal holidays.

          Code:  The Internal Revenue Code of 1986, as amended, and the
regulations promulgated thereunder.

          Common Areas: The lobby, plaza and sidewalk areas, subterranean garage
(if any) and other similar areas of general access and the areas on multi-tenant
floors in the Building devoted to corridors, elevator lobbies, restrooms,  and
other similar facilities serving the Premises.

          Comparable Buildings:  First-class office buildings of comparable age
and quality in the Financial District of San Francisco, California.

          Excluded Expenses:  (a) Taxes; (b) franchise or income taxes imposed
upon Landlord; (c) mortgage amortization and interest; (d) leasing commissions;
(e) the cost of tenant installations and decorations incurred in connection with
preparing space for any Building tenant, including workletters and concessions;
(f) fixed rent under Superior Leases, if any; (g) management fees equal to the
greater of (A) 3% of the gross rentals collected for the Building and (B) fees
charged by Landlord or related entities for the management by any of them of
other first class properties in the area of the Building; (h) wages, salaries
and benefits paid to any persons above the grade of Building Manager and their
immediate supervisor; (i) legal and accounting fees relating to (A) disputes
with tenants, prospective tenants or other occupants of the Building, (B)
disputes with purchasers, prospective purchasers, mortgagees or prospective
mortgagees of the Building or the Real Property or any part of either, or (C)
negotiations of leases, contracts of sale or mortgages; (j) costs of services
provided to other tenants of the Building on a "rent-inclusion" basis which are
not provided to Tenant on such basis; (k) costs that are reimbursed out of
insurance, warranty or condemnation proceeds, or which are reimbursable by
Tenant or other tenants other than pursuant to an expense escalation clause; (l)
costs in the nature of penalties or fines; (m) costs for services, supplies or
repairs paid to any related entity in excess of costs that would be payable in
an "arm's length" or unrelated situation for comparable services, supplies or
repairs; (n) allowances, concessions or other costs and expenses of improving or
decorating any demised or demisable space in the Building; (o) appraisal,
advertising and promotional expenses in connection with leasing of the Building;
(p) the costs of installing, operating and maintaining a specialty improvement,
including a cafeteria, lodging or private dining facility, or an athletic,
luncheon or recreational club; (q) any costs or expenses (including fines,
interest, penalties and legal fees) arising out of Landlord's failure to timely
pay Operating Expenses or Taxes; (r) costs incurred in connection with the
removal, encapsulation or other treatment of asbestos or any other Hazardous
Materials (classified as such on the Effective Date) existing in the Premises as
of the date hereof, (s) the cost of capital improvements other than those
expressly included in

                                      B-1
<PAGE>

Operating Expenses pursuant to Section 7.1; (t) bad debt expenses and interest,
principal, points and fees on debts or amortization on any mortgage or other
debt instrument encumbering the Building or the Land; (u) rentals for items
which if purchased, rather than rented, would constitute a capital cost not
includable within Operating Expense but excluding small tools, Building
management office equipment and equipment rented on a temporary basis while
performing repairs at the Building; (v) depreciation, amortization and interest
payments, except on equipment, materials, tools, supplies and vendor-type
equipment purchased by Landlord to enable Landlord to supply services Landlord
might otherwise contract for with a third party where such depreciation,
amortization and interest payments would otherwise have been included in the
charge for such third party's services, all as determined in accordance with
generally accepted accounting principles, consistently applied, and when
depreciation or amortization is permitted or required, the item shall be
amortized over its reasonably anticipated useful life; (w) costs, including
permit, license and inspection costs, incurred with respect to the installation
of tenants; or other occupants' improvements or incurred in renovating or
otherwise improving, decorating, painting or redecorating vacant space for
tenants or other occupants of the Building; (x) all items and services for which
Tenant directly reimburses Landlord or pays third persons for such services
which are otherwise not offered by Landlord to all tenants of the Building or
which Landlord provides selectively to one or more tenants of the Building which
are not customary for normal office use; (y) costs incurred by Landlord due to
the violation by Landlord or any tenant of the terms and conditions of any lease
of space in the Building; (z) salaries and/or benefits attributable to Building
property management personnel above the level of the Building's manager's
supervisor; (aa) rent for any office space occupied by Building management
personnel to the extent the size or rental rate for such office space exceeds
the size or fair market rental value of office space occupied by management
personnel of Comparable Buildings; (ab) Landlord's general corporate overhead
and general and administrative expenses as distinguished from the costs of the
management, operation, maintenance and repair of the Building; (ac) any
compensation paid to clerks, attendants or other persons in commercial
concessions operated by Landlord; (ad) costs arising from the negligence or
willful misconduct of Landlord or Landlord's Agent or their respective agents,
employees, contractors or providers of materials or services; (ae) costs arising
from Landlord's charitable or political contributions; (af) costs for the
acquisition of sculpture, paintings or other objects of art provided that
Operating Expenses shall include the cost of maintaining, insuring and securing
such items in the Common Areas only; and (ag) costs associated with the
operation of the business of the entity which constitutes Landlord as the same
are distinguished from the costs of operation of the Building, including certain
accounting and legal matters, costs of defending any lawsuits with any mortgagee
(except as the actions of Tenant may be in issue), costs of selling,
syndicating, financing, mortgaging or hypothecating any of Landlord's interest
in the Building, costs incurred in connection with any disputes between Landlord
and its employees, between Landlord and Building management, or between Landlord
and other tenants or occupants.

          Governmental Authority:  The United States of America, the City and
County of San Francisco, or State of California, or any political subdivision,
agency, department, commission, board, bureau or instrumentality of any of the
foregoing, now existing or hereafter created, having jurisdiction over the Real
Property.

          Hazardous Materials:  Any substances, materials or wastes currently or
in the future deemed or defined in any Requirement as "hazardous substances,"
"toxic substances," "contaminants," "pollutants" or words of similar import.

          HVAC Systems:  The Building System designed to provide heating,
ventilation and air conditioning.

          Indemnitees:  Landlord, Landlord's Agent, each Mortgagee and Lessor,
and each of their respective direct and indirect partners, officers,
shareholders, directors, members, managers, trustees, beneficiaries, employees,
principals, contractors, servants, agents, and representatives.

          Lessor:  A lessor under a Superior Lease.

                                      B-2
<PAGE>

          Losses:  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) incurred in connection
with any claim, proceeding or judgment and the defense thereof, and including
all costs of repairing any damage to the Premises or the Building or the
appurtenances of any of the foregoing to which a particular indemnity and hold
harmless agreement applies.

          Mortgage(s):  Any mortgage, trust indenture or other financing
document which may now or hereafter affect the Premises, the Real Property, 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(s):  Any mortgagee, trustee or other holder of a Mortgage.

          Ordinary Business Hours:  8:00 a.m. to 6:00 p.m. on Business Days.

          Prohibited Use:  Any use or occupancy of the Premises that in
Landlord's reasonable judgment would: (a) cause damage to the Building or any
equipment, facilities or other systems therein; (b) impair the appearance of the
Building; (c) interfere with the efficient and economical maintenance, operation
and repair of the Premises or the Building or the equipment, facilities or
systems thereof; (d) adversely affect any service provided to, and/or the use
and occupancy by, any Building tenant or occupants; (e) violate the certificate
of occupancy issued for the Premises or the Building; (f) materially and
adversely affect the first-class image of the Building or (g) result in protests
or civil disorder or commotions at, or other disruptions of the normal business
activities in, the Building.  Prohibited Use also includes the use of any part
of the Premises for: (i) a restaurant or bar; (ii) the preparation, consumption,
storage, manufacture or sale of food or beverages (except in connection with
vending machines (provided that each machine, where necessary, shall have a
waterproof pan thereunder and be connected to a drain) and/or warming kitchens
installed for the use of Tenant's employees only), liquor, tobacco or drugs
(provided occupants are not prohibited from taking prescription medicines or
carrying tobacco products as opposed to smoking the same); (iii) the business of
photocopying, multilith or offset printing (except photocopying in connection
with Tenant's own business); (iv) a typing or stenography business; (v) a school
or classroom (except for internal training); (vi) lodging or sleeping; (vii) the
operation of retail facilities (meaning a business whose primary patronage
arises from the generalized solicitation of the general public to visit Tenant's
offices in person without a prior appointment) of a savings and loan association
or retail facilities of any financial, lending, securities brokerage or
investment activity; (viii) a payroll office; (ix) a barber, beauty or manicure
shop; (x) an employment agency or similar enterprise; (xi) offices of any
Governmental Authority, any foreign government, the United Nations, or any
agency or department of the foregoing; (xii) the manufacture, retail sale,
storage of merchandise or auction of merchandise, goods or property of any kind
to the general public which could reasonably be expected to create a volume of
pedestrian traffic substantially in excess of that normally encountered in the
Premises; (xiii) the rendering of medical, dental or other therapeutic or
diagnostic services; or (xiv) any illegal purposes or any activity constituting
a nuisance.

          Requirements:  All applicable present and future laws, rules, orders,
ordinances, regulations, statutes, requirements, codes and executive orders,
extraordinary and ordinary of (i) all Governmental Authorities, including the
Americans With Disabilities Act, 42 U.S.C. (S)12,101 (et seq.), and any law of
like import, and all rules, regulations and government orders with respect
thereto, and any of the foregoing relating to Hazardous Materials, environmental
matters, public health and safety matters, (ii) any applicable fire rating
bureau or other body exercising similar functions, affecting the Real Property
or the maintenance, use or occupation thereof, or any street, avenue or sidewalk
comprising a part of or in front thereof or any vault in or under the same,
(iii) all requirements of all insurance bodies affecting the Premises and (iv)
all utility service providers.

                                      B-3
<PAGE>

          Rules and Regulations:  The rules and regulations annexed to and made
a part of this Lease as Exhibit F, as they may be modified from time to time by
Landlord.

          Specialty Alterations:  Alterations which are not standard office
installations such as commercial kitchens, executive bathrooms, raised computer
floors, computer installations, safe deposit boxes, vaults, libraries or file
rooms requiring reinforcement of floors, internal staircases, conveyors,
dumbwaiters, and other Alterations of a similar character.  All Specialty
Alterations shall be deemed to be Above Building Standard Installations.

          Substantial Completion:  As to any construction performed by any party
in the Premises, including the Initial Installations, any Alterations, or
Landlord's Work, "Substantial Completion" or "Substantially Completed" means
that such work has been completed, as reasonably determined by Landlord's
architect, in accordance with (a) the provisions of this Lease applicable
thereto, (b) the plans and specifications for such work, and (c) all applicable
Requirements, except for minor details of construction, decoration and
mechanical adjustments, if any, the noncompletion of which does not materially
interfere with Tenant's use of the Premises.

          Superior Lease(s):  Any ground or underlying lease of the Real
Property or any part thereof heretofore or hereafter made by Landlord and all
renewals, extensions, supplements, amendments, modifications, consolidations,
and replacements thereof.

          Tenant Party:  Tenant and Tenant's agents, contractors,
subcontractors, employees, invitees or licensees.

          Tenant's Property:  Tenant's movable fixtures and movable partitions,
telephone and other equipment, computer systems, trade fixtures, furniture,
furnishings, and other items of personal property which are removable without
material damage to the Building.

          Unavoidable Delays:  Any inability to fulfill or delay in fulfilling
any obligations of a party under this Lease expressly or impliedly to be
performed by a party (including inability to make or delay in making any
repairs, additions, alterations, improvements or decorations or Landlord's
inability to supply or delay in supplying any equipment or fixtures), if such
party's inability or delay is due to or arises by reason of strikes, labor
troubles or by accident, or by any cause whatsoever beyond such party's
reasonable control, including governmental preemption in connection with a
national emergency, compliance with Requirements, shortages, or unavailability
of labor, fuel, steam, water, electricity or materials, or delays caused by the
other party , mechanical breakdown, acts of God, enemy action, civil commotion,
fire or other casualty.

                                      B-4
<PAGE>

                                   EXHIBIT C

                                   Workletter

     This Workletter (the "Workletter") is attached as an exhibit to that
certain Lease (the "Lease"), dated as of the date hereof, between TST 555/575
Market, L.L.C. (the "Landlord") and CMGI, Inc. (the "Tenant"), wherein Tenant is
leasing certain office space (the "Premises") at 575 Market Street, San
Francisco, California (the "Building"), as more particularly described in the
Lease.  Landlord and Tenant hereby agree as follows:

     1.   General.

          (a)  The purpose of this Workletter is to set forth how the interior
improvements in the Premises (the "Improvements") are to be constructed, who
will do the construction of the Improvements, who will pay for the construction
of the Improvements, and the time schedule for completion of the construction of
the Improvements.

          (b)  Except as defined in this Workletter to the contrary, all terms
utilized in this Workletter shall have the same meaning as the defined terms in
the Lease.

          (c)  The terms, conditions and requirements of the Lease, except where
clearly inconsistent or inapplicable to this Workletter, are incorporated into
this Workletter.

     2.   Proposed and Final Plans.

          (a)  As soon as reasonably possible following the Effective Date,
Tenant shall cause to be prepared and delivered to Landlord, for Landlord's
approval, the following proposed drawings ("Proposed Plans") for all
improvements Tenant desires to complete or have completed in the Premises (the
"Improvements"); all of Landlord's reviews and approvals hereunder to be in
accordance with the standards set forth in Article 5 of the Lease:

               (i)    Architectural drawings (consisting of floor construction
plan, ceiling lighting and layout, power, and telephone plan).

               (ii)   Mechanical drawings (consisting of HVAC, electrical,
telephone, and plumbing).

               (iii)  Finish schedule (consisting of wall finishes and floor
finishes and miscellaneous details).

          (b)  All architectural drawings shall be prepared at Tenant's sole
cost and expense by a licensed architect designated by Tenant and approved by
Landlord, whom Tenant shall employ. Landlord hereby approves Visnick & Caulfield
Associates, Inc. and Dowler Grauman Associates. Tenant shall deliver one set of
reproducible architectural drawings to Landlord. All mechanical drawings shall
be prepared at Tenant's sole cost and expense by a licensed engineer designated
by Landlord, whom Tenant shall employ.

          (c)  Within 10 days after Landlord's receipt of the architectural
drawings, Landlord shall advise Tenant of any changes or additional information
required to obtain Landlord's approval; provided Landlord shall endeavor to
complete such review prior to the expiration of such 10-day period.

          (d)  Within 10 days after receipt of mechanical drawings, Landlord
shall advise Tenant of any changes required to obtain Landlord's approval;
provided Landlord shall endeavor to complete such review prior to the expiration
of such 10-day period.

          (e)  If Landlord disapproves of, or requests additional information
regarding the Proposed Plans, Tenant shall, within 5 days thereafter, revise the
Proposed Plans disapproved by Landlord and resubmit such plans to Landlord or
otherwise provide such additional information to Landlord.  Landlord shall,
within 10 days after receipt of Tenant's revised plans, advise Tenant of any

<PAGE>

additional changes which may be required to obtain Landlord's approval; provided
Landlord shall endeavor to complete such review prior to the expiration of such
10-day period.  If Landlord disapproves the revised plans specifying the reason
therefor, or requests further additional information, Tenant shall, within 5
days of receipt of Landlord's required changes, revise such plans and resubmit
them to Landlord or deliver to Landlord such further information as Landlord has
requested.  Landlord shall, again within 10 days after receipt of Tenant's
revised plans, advise Tenant of further changes, if any, required for Landlord's
approval.  This process shall continue until Landlord has approved Tenant's
revised Proposed Plans.  "Final Plans" shall mean the Proposed Plans, as
revised, which have been approved by Landlord and Tenant in writing.  Landlord
agrees not to withhold its approval unreasonably.  Concurrently with Landlord's
approval of the Final Plans Landlord will advise Tenant of Landlord's
determination of whether any of the Improvements shown thereon constitute Above
Building Standard Installations.

          (f)  All Proposed Plans and Final Plans shall comply with all
applicable Requirements and with the requirements of Landlord's fire insurance
underwriters.  Neither review nor approval by Landlord of the Proposed Plans and
resulting Final Plans shall constitute a representation or warranty by Landlord
that such plans either (i) are complete or suitable for their intended purpose,
or (ii) comply with applicable Requirements or any insurance requirements, it
being expressly agreed by Tenant that Landlord assumes no responsibility or
liability whatsoever to Tenant or to any other person or entity for such
completeness, suitability or compliance.  Tenant shall not make any changes in
the Final Plans without Landlord's prior written approval, which shall not be
unreasonably withheld or delayed; provided that Landlord may, in the exercise of
its sole and absolute discretion, disapprove any proposed changes adversely
affecting the Building's structure, systems, equipment or the appearance or
value of the Building.  The Final Plans shall include the installation of a new
Building Standard ceiling within the Premises.

          (g)  As soon as reasonably possible following Landlord's and Tenant's
approval of the Final Plans, Landlord shall enter into a construction contract
(the "Contract") with Webcor Builders (the "Contractor"), the dollar amount of
which Contract shall be subject to Tenant's approval, which approval shall not
be unreasonably withheld or unduly delayed, and no failure by Tenant to approve
the dollar amount of the Contact shall extend the Rent Commencement Date.
Landlord shall use reasonable efforts to cause the Contractor to obtain market
pricing for each trade.  If Tenant does not accept the dollar amount of the
Contract, Tenant shall advise Landlord within 5 days thereafter whether (a)
Tenant desires Landlord to competitively bid the Initial Installations (or
portions thereof); (b) whether Tenant desires to revise the Final Plans to
reduce the cost of the Initial Installations; or (c) whether Tenant desires to
assume responsibility for construction of the Initial Installations.  The
Contract shall provide for progress payments, and Tenant shall pay for the
entire cost of the Improvements in excess of the respective Landlord's
Contribution (as hereinafter defined) on or before the execution of the
Contract.  The cost of the Improvements shall include the cost of (i) all work
performed by Landlord, Contractor, Architect or anyone else on behalf of Tenant
(including the demolition and removal of all Hauserman partitions if Tenant does
not elect to reuse the same in connection with the build-out of the
Improvements, it being understood that ownership of the partitions so removed is
vested in Landlord), (ii) all materials and labor furnished on Tenant's behalf,
(iii) preparing the Proposed Plans and Final Plans, and (iv) building permits
and engineering fees.  Landlord shall be responsible for all costs of
transporting any such partitions to its storage location as determined by
Landlord.

          (h)  Landlord shall then instruct the Contractor to build the
Improvements indicated on the Final Plans as soon thereafter as reasonably
possible, consistent with industry custom and procedure, at Tenant's sole and
entire cost, except for Landlord's Contribution.  Landlord shall use its
commercially reasonable efforts to cause the Premises to be Substantially
Complete by the Rent Commencement Date, but no failure by Landlord to achieve
Substantial Completion by such date shall extend the Rent Commencement Date.

                                      C-2
<PAGE>

          (i)  Tenant shall reimburse to Landlord the actual costs incurred by
Landlord to approve all plans, specifications and materials submitted pursuant
to this Section 2, and such reimbursement shall occur by Landlord's deducting
such costs from the Landlord's Contribution.  Tenant shall also pay to Landlord
a supervision fee in an amount equal to 5% of the cost of the Improvements for
Landlord's services in connection with this Workletter, which supervision fee
will be deducted from Landlord's Contribution.

          (j)  Upon receipt of the Proposed Plans (and prior to Landlord's
approval thereof), Landlord shall file for a building permit.

     3.   Landlord's Contribution.  Landlord will pay an amount (the "Landlord's
Contribution") toward the cost of the planning, design and construction of the
Improvements in an amount not to exceed $446,840.00.  If the cost of the
planning, design and construction of the Improvements exceeds Landlord's
Contribution, the difference shall be borne by Tenant and paid by Tenant to
Landlord at the time the Contract or any change order is signed.  If Tenant
requests any changes to the Final Plans, Landlord shall not unreasonably
withhold its consent to any such changes, provided the changes do not adversely
affect the Building's structure, systems, equipment, appearance or value, but,
if such changes increase the cost of constructing the Improvements shown on the
Final Plans, Tenant shall bear such costs and shall pay such estimated increased
costs to Landlord at such time as the request is approved by Landlord.  If the
actual increased costs are greater than the estimated increased costs, Tenant
shall pay the difference in increased costs to Landlord with 30 days after
written demand therefor; similarly, if the actual increased costs are less than
the estimated increased costs, Landlord shall credit the amount of such
difference to the unfunded balance of Landlord's Contribution.  The costs
charged by Landlord to Tenant caused by Tenant's requesting changes to the
Improvements or the Final Plans shall be equal to the sum of (a) the amount of
money Landlord has to pay to cause the Improvements, as reflected by revised
Final Plans, to be constructed above the costs that Landlord would have had to
pay to cause the Improvements to be constructed if no changes had been made to
the Final Plans ("Differential"), (b) any cancellation fees, reshipping charges
or any other similar costs incurred by Landlord in connection therewith, and (c)
an amount equal to ten percent (10%) of the Differential to compensate Landlord
for its time and efforts in connection with such changes.  The failure of Tenant
to pay any amounts due hereunder within ten (10) days of the date such sums are
due and payable shall constitute an Event of Default under the Lease.  Whenever
possible and practical, Landlord will utilize, for the construction of the
Improvements, the items and materials designated in the Final Plans; provided,
however, that whenever Landlord reasonably determines in its judgment that it is
not practical or efficient to use such materials, Landlord shall have the right,
upon receipt of Tenant's consent, to substitute comparable items and materials.

     4.   Miscellaneous.

          (a)  Tenant agrees that, in connection with the Improvements and its
use of the Premises prior to the commencement of the Term of the Lease, Tenant
shall have those duties and obligations with respect thereto that it has
pursuant to the Lease during the Term, except the obligation for payment of
rent, and further agrees that, except where caused by Landlord's gross
negligence or willful misconduct, Landlord shall not be liable in any way for
injury, loss, or damage which may occur to any of the Improvements or
installations made in the Premises, or to any personal property placed therein,
the same being at Tenant's sole risk.

          (b)  Except as expressly set forth in the Lease, Landlord has no other
agreement with Tenant and Landlord has no other obligation to do any other work
or pay any amounts with respect to the Premises.  Any other work in the Premises
which may be permitted by Landlord pursuant to the terms and conditions of the
Lease shall be done at Tenant's sole cost and expense and in accordance with the
terms and conditions of the Lease.

          (c)  This Workletter shall not be deemed applicable to any additional
space added to the original Premises at any time or from time to time, whether
by any options under the Lease or

                                      C-3
<PAGE>

otherwise, or to any portion of the original Premises or any additions thereto
in the event of a renewal or extension of the initial term of the Lease, whether
by any options under the Lease or otherwise, unless expressly so provided in the
Lease or any amendment or supplement thereto.

          (d)  The failure by Tenant to pay any monies due Landlord pursuant to
this Workletter within the time period herein stated shall be deemed a default
under the terms of the Lease for which Landlord shall be entitled to exercise
all remedies available to Landlord for nonpayment of Rent and Landlord, may, if
it so elects, discontinue construction of the Improvements until all such sums
are paid and Tenant has otherwise cured such default.  All late payments shall
bear interest pursuant to Section 16.6 of the Lease.

          (e)  Neither Landlord's Agent nor the partners or members comprising
Landlord or Landlord's Agent, nor the shareholders (nor any of the partners
comprising same), directors, officers or shareholders of any of the foregoing
(collectively, the "Parties") shall be liable for the performance of Landlord's
obligations under this Workletter.  Tenant shall look solely to Landlord to
enforce Landlord's obligations hereunder and shall not seek any damages against
any of the Parties.  The liability of Landlord for Landlord's obligations under
this Workletter shall not exceed and shall be limited to Landlord's interest in
the Building and Tenant shall not look to the property or assets of any of the
Parties in seeking either to enforce Landlord's obligations under this
Workletter or to satisfy a judgment for Landlord's failure to perform such
obligations.  Upon a sale of the Building by Landlord, Tenant shall look solely
to the buyer to enforce its rights under this Workletter, and, if and to the
extent such buyer has not assumed Landlord's duties, obligations and liabilities
hereunder, Tenant may only look to the actual cash proceeds received by Landlord
in connection with such sale in seeking to satisfy a judgment for Landlord's
failure to perform its obligations under this Workletter.

                                      C-4
<PAGE>

                                   EXHIBIT D

                               Design Standards

          (A)  HVAC.  Building Standard heating, ventilation, cooling shall
               ----
generally meet the following design criteria during Ordinary Business Hours:

          The HVAC System shall be capable of maintaining 78 degrees Fahrenheit
          (Title 24) plus or minus 2 degrees, when outdoor conditions are 79
          degrees Fahrenheit dry bulb and 63 degrees Fahrenheit wet bulb.  The
          HVAC System shall be capable of maintaining 72 degrees Fahrenheit at
          outdoor temperature 39 degrees Fahrenheit dry bulb.  Additional system
          capacity, exceeding Title 24 requirements, is available such that the
          HVAC system can maintain 75 degrees Fahrenheit plus or minus 2 degrees
          upon application of the following design data.  The HVAC System is
          designed based upon (i) electrical usage of 4 watts per usable square
          foot for all purposes (lighting and power), (ii) occupancy rate of 1
          person per usable 150 square feet, and (iii) shades fully drawn and
          partially closed.  The Building's HVAC system has been designed to
          provide 20 cfm of outside air based upon 1 occupant per 150 usable
          square feet or 0.15 cfm outside air per usable square foot.

          Use of the Premises, or any part thereof, in a manner exceeding the
foregoing design conditions or rearrangement of partitioning after the initial
preparation of the Premises which interferes with normal operation of the air-
conditioning service in the Premises may require changes in the air-conditioning
system serving the Premises.

          (b)  Electrical.  The Building Electrical System serving the Premises
               ----------
is designed to provide:

                 (i)   1.5 watts per usable square foot of high voltage (480/277
volt) connected power for lighting; and

                 (ii)  3.5 watts per usable square foot of low voltage (120/280
volt) connected power for convenience receptacles.

                                      D-1
<PAGE>

                                   EXHIBIT E

                            Cleaning Specifications

GENERAL CLEANING

NIGHTLY

     General Offices:

     1.   All hard surfaced flooring to be swept using approved dustdown
          preparation.

     2.   Carpet sweep all carpets, moving only light furniture (desks, file
          cabinets, etc. not to be moved).

     3.   Hand dust and wipe clean all furniture, fixtures and window sills.

     4.   Empty all waste receptacles and remove wastepaper.

     5.   Wash clean all Building water fountains and coolers.

     6.   Sweep all private stairways.

     Lavatories:

     1.   Sweep and wash all floors, using proper disinfectants.

     2.   Wash and polish all mirrors, shelves, bright work and enameled
          surfaces.

     3.   Wash and disinfect all basins, bowls and urinals.

     4.   Wash all toilet seats.

     5.   Hand dust and clean all partitions, tile walls, dispensers and
          receptacles in lavatories and restrooms.

     6.   Empty paper receptacles, fill receptacles and remove wastepaper.

     7.   Fill toilet tissue holders from tenant supply.

     8.   Empty and clean sanitary disposal receptacles.

WEEKLY

     1.   Vacuum all carpeting and rugs.

     2.   Dust all door louvers and other ventilating louvers within a person's
          normal reach.

     3.   Wipe clean all brass and other bright work.

QUARTERLY

     High dust premises complete including the following:

     1.   Dust all pictures, frames, charts, graphs and similar wall hangings
          not reached in nightly cleaning.

     2.   Dust all vertical surfaces, such as walls, partitions, doors, bucks
          and other surfaces not reached in nightly cleaning.

     3.   Dust all venetian blinds.

     4.   Wash all windows.

                                      E-1
<PAGE>

                                   EXHIBIT F

                             Rules and Regulations

          1.   Nothing shall be attached to the outside walls of the Building.
No curtains, blinds, shades, screens or other obstructions shall be attached to
or hung in or used in connection with any exterior window or entry door of the
Premises, without the prior consent of Landlord.

          2.   No sign, advertisement, notice or other lettering visible from
the exterior of the Premises shall be exhibited, inscribed, painted or affixed
to any part of the Premises without the prior written consent of Landlord. All
lettering on doors shall be inscribed, painted or affixed in a size, color and
style acceptable to Landlord.

          3.   The grills, louvers, skylights, windows and doors that reflect or
admit light and/or air into the Premises or Common Areas shall not be covered or
obstructed by Tenant, nor shall any articles be placed on the window sills,
radiators or convectors.

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

          5.   The sidewalks, entrances, passages, courts, elevators,
vestibules, stairways, corridors or halls shall not be obstructed or encumbered
by any Tenant or used for any purposes other than ingress of egress to and from
the Premises and for delivery of merchandise and equipment in a prompt and
efficient manner, using elevators and passageways designated for such delivery
by Landlord.

          6.   Except in those areas designated by Tenant as "security areas,"
all locks or bolts of any kind shall be operable by the Building's Master Key.
No locks shall be placed upon any of the doors or windows by Tenant, nor shall
any changes be made in locks or the mechanism thereof which shall make such
locks inoperable by the Building's Master Key. Tenant shall, upon the
termination of its Lease, deliver to Landlord all keys of stores, offices and
lavatories, either furnished to or otherwise procured by Tenant and in the event
of the loss of any keys furnished by Landlord, Tenant shall pay to Landlord the
cost thereof.

          7.   Tenant shall keep the entrance door to the Premises closed at all
times.

          8.   All movement in or out of any freight, furniture, boxes, crates
or any other large object or matter of any description must take place during
such times and in such elevators as Landlord may prescribe. Landlord reserves
the right to inspect all articles to be brought into the Building and to exclude
from the Building all articles which violate any of these Rules and Regulations
or the Lease of which these Rules and Regulations are a part. Landlord may
require that any person leaving the public areas of the Building with any
article (but not standard items such as brief cases, etc., carried by office
personnel) to submit a pass, signed by an authorized person, listing each
article being removed, but the establishment and enforcement of such requirement
shall not impose any responsibility on Landlord for the protection of any Tenant
against the removal of property from the Premises.

          9.   All hand trucks shall be equipped with rubber tires, side guards
and such other safeguards as Landlord may require.

          10.  None of Tenant's employees, visitors or contractors shall be
permitted to have access to the Building's roof, mechanical, electrical or
telephone rooms without permission from Landlord.

          11.  Tenant shall not lay floor tile, or other similar floor covering
so that the same shall come in direct contact with the concrete floor of the
Premises and, if such floor covering is desired to be used, an interlining of
builder's deadening felt shall be first affixed to the floor by a paste or other

                                      F-1
<PAGE>

material, soluble in water; the use of cement or other similar adhesive material
being expressly prohibited.

          12.  Tenant shall not permit or suffer the Premises to be occupied or
used in a manner offensive or objectionable to Landlord or other occupants of
the Building by reason of noise, odors, vibrations or interfere in any way with
other tenants or those having business therein.

          13.  Tenant shall not employ any person or persons other than the
janitor of Landlord for the purpose of cleaning the Premises, unless otherwise
agreed to by Landlord. Tenant shall not cause any unnecessary labor by reason of
such Tenant's carelessness or indifference in the preservation of good order and
cleanliness.

          14.  Tenant shall store all its trash and recyclables within its
Premises. No material shall be disposed of which may result in a violation of
any Requirement. All refuse disposal shall be made only though entry ways and
elevators provided for such purposes and at such times as Landlord shall
designate. Tenant shall use the Building's hauler.

          15.  Tenant shall not mark, paint, drill into or in any way deface any
part of the Building, except with the prior written consent of Landlord in the
case of the Premises, which consent shall not be unreasonably withheld. No
boring, cutting or stringing of wires shall be permitted, except with prior
consent of Landlord, and as Landlord may direct.

          16.  The water and wash closets, electrical closets, mechanical rooms,
fire stairs and other plumbing fixtures shall not be used for any purposes other
than those for which they were constructed and no sweepings, rubbish, rags,
acids or other substances shall be deposited therein. All damages resulting from
any misuse of the fixtures shall be borne by Tenant where a Tenant Party caused
the same.

          17.  Tenant, before closing and leaving the Premises, shall use
reasonable efforts to see that all lights and water faucets are turned off. All
entrance doors in the Premises shall be kept locked by Tenant when the Premises
are not in use.

          18.  No bicycles, in-line roller skates, vehicles or animals of any
kind (except for seeing eye dogs) shall be brought into or kept by any Tenant in
or about the Premises or the Building.

          19.  Canvassing or soliciting in the Building is prohibited.

          20.  Employees of Landlord or Landlord's Agent shall not perform any
work or do anything outside of the regular duties, unless under special
instructions from the office of Landlord or in response to any emergency
condition.

          21.  Tenant is responsible for the delivery and pick up of all mail
from the United States Post Office.

          22.  Landlord reserves the right to exclude from the Building during
other than Ordinary Business Hours all persons who do not present a valid
Building pass. Tenant shall be responsible for all persons for whom a pass shall
be issued at the request of Tenant and shall be liable to Landlord for all acts
of such persons.

          23.  Landlord shall not be responsible to Tenant or to any other
person for the non-observance or violation of these Rules and Regulations by any
other tenant or other person. Tenant shall be deemed to have read Rules and
Regulations and to have agreed to abide by them as a condition to its occupancy
of the Premises.

                                      F-2
<PAGE>

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

                                   EXHIBIT G

                     MORGAN STANLEY MORTGAGE CAPITAL INC.
                                   (Lender)

                                    - and -

                                  CMGI, INC.
                                   (Tenant)

                   ----------------------------------------

                        SUBORDINATION, NON-DISTURBANCE
                           AND ATTORNMENT AGREEMENT

                   ----------------------------------------

                   Dated:         January ___, 2000

                   Location:      575 Market Street, San Francisco, CA

                   Block:         3708
                   Lot:           58
                   County:        San Francisco

                   PREPARED BY AND UPON
                   RECORDATION RETURN TO:

                   Messrs. Cadwalader, Wickersham & Taft
                   100 Maiden Lane
                   New York, New York 10038
                   Attention: John M. Zizzo

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

                                      G-1
<PAGE>

            SUBORDINATION, NON-DISTURBANCE AND ATTORNMENT AGREEMENT

          THIS SUBORDINATION, NON-DISTURBANCE AND ATTORNMENT AGREEMENT (this
"Agreement") is made as of the ____ day of January, 2000 by and between MORGAN
STANLEY MORTGAGE CAPITAL INC., having an address at 1585 Broadway, 38/th/ Floor,
New York, New York 10036 ("Lender") and CMGI, INC., having an address at 100
Brickstone Square, Andover, Massachusetts 01810 ("Tenant").

                                   RECITALS:

          A.   Lender has made a loan in the approximate amount of $170,000,000
to Landlord (defined below), which Loan is given pursuant to the terms and
conditions of that certain loan agreement dated December 10, 1999, between
Lender and Landlord (the "Loan Agreement"). The Loan is evidenced by a certain
Promissory Note dated December 10, 1999, given by Landlord to Lender (the
"Note") and secured by a certain Deed of Trust, Assignment of Leases and Rents
and Security Agreement (the "Mortgage"), dated December 10, 1999, and recorded
on December 15, 1999 as Series No. G705093 in the Official Records of the City
and County of San Francisco, given by Landlord to Lender which encumbers the fee
estate of Landlord in certain premises described in Exhibit A attached hereto
(the "Property");

          B.   Tenant has the right to occupy a portion of the Property under
and pursuant to the provisions of a certain lease dated January ____, 2000,
between TST 555/575 Market, L.L.C., as landlord ("Landlord") and Tenant, as
tenant (the "Lease"); and

          C.   Tenant has agreed to subordinate the Lease to the Mortgage and to
the lien thereof and Lender has agreed to grant non-disturbance to Tenant under
the Lease on the terms and conditions hereinafter set forth.

                                  AGREEMENT:

          For good and valuable consideration, Tenant and Lender agree as
follows:

          1.   Subordination.  Tenant agrees that the Lease and all of the
               -------------
terms, covenants and provisions thereof and all rights, remedies and options of
Tenant thereunder are and shall at all times continue to be subject and
subordinate in all respects to the Mortgage and to the lien thereof and all
terms, covenants and conditions set forth in the Mortgage and the Loan Agreement
including without limitation all renewals, increases, modifications, spreaders,
consolidations, replacements and extensions thereof and to all sums secured
thereby.

          2.   Non-Disturbance.  Lender agrees that if any action or proceeding
               ---------------
is commenced by Lender for the foreclosure of the Mortgage or the sale of the
Property, Tenant shall not be named as a party therein unless such joinder shall
be required by law, provided, however, such joinder shall not result in the
termination of the Lease or disturb the Tenant's possession or use of the
premises demised thereunder, and the sale of the Property in any such action or
proceeding and the exercise by Lender of any of its other rights under the Note,
the Mortgage and the Loan Agreement shall be made subject to all rights of
Tenant under the Lease, provided that at the time of the commencement of any
such action or proceeding or at the time of any such sale or exercise of any
such other rights (a) the term of the Lease shall have commenced pursuant to the
provisions thereof, (b) Tenant, or a successor to Tenant, subtenant or assignee,
shall be in possession of the premises demised under the Lease, (c) the Lease
shall be in full force and effect and (d) Tenant shall not be in default under
any of the

                                      G-2
<PAGE>

terms, covenants or conditions of the Lease or of this Agreement on Tenant's
part to be observed or performed beyond the expiration of any applicable notice
or grace periods.

          3.   Attornment.  Lender and Tenant agree that upon the conveyance of
               ----------
the Property by reason of the foreclosure of the Mortgage or the acceptance of a
deed or assignment in lieu of foreclosure or otherwise, the Lease shall not be
terminated or affected thereby (at the option of the transferee of the Property
(the "Transferee") if the conditions set forth in Section 2 above have not been
met at the time of such transfer) but shall continue in full force and effect as
a direct lease between the Transferee and Tenant upon all of the terms,
covenants and conditions set forth in the Lease and in that event, Tenant agrees
to attorn to the Transferee and the Transferee shall accept such attornment,
provided, however, that the provisions of the Mortgage and the Loan Agreement
shall govern with respect to the disposition of any casualty insurance proceeds
or condemnation awards and the Transferee shall not be (a) obligated to complete
any construction work required to be done by Landlord pursuant to the provisions
of the Lease or to reimburse Tenant for any construction work done by Tenant,
(b) liable (i) for Landlord's failure to perform any of its obligations under
the Lease which have accrued prior to the date on which the Transferee shall
become the owner of the Property (providing that nothing set forth herein shall
be deemed to negate a Transferee's obligation to perform the Landlord's
obligations under the Lease arising after the date the Transferee becomes owner
of the Property), or (ii) for any act or omission of Landlord, whether prior to
or after such foreclosure or sale, (c) required to make any repairs to the
Property or to the premises demised under the Lease required as a result of
fire, or other casualty or by reason of condemnation unless the Transferee shall
be obligated under the Lease to make such repairs and shall have received
sufficient casualty insurance proceeds or condemnation awards to finance the
completion of such repairs, (d) required (i) to make any capital improvements to
the Property or to the premises demised under the Lease which Landlord may have
agreed to make, but had not completed, or (ii) to perform or provide any
services, in either case, not required to be made or be performed by the
Landlord under the Lease, (e) subject to any offsets, defenses, abatements or
counterclaims which shall have accrued to Tenant against Landlord prior to the
date upon which the Transferee shall become the owner of the Property, (f)
liable for the return of rental security deposits, if any, paid by Tenant to
Landlord in accordance with the Lease unless such sums are actually received by
the Transferee, (g) bound by any payment of rents, additional rents or other
sums which Tenant may have paid more than one (1) month in advance to any prior
Landlord unless (i) such sums are actually received by the Transferee or (ii)
such prepayment shall have been expressly approved of by the Transferee, (h)
bound to make any payment to Tenant which was required under the Lease, or
otherwise, to be made prior to the time the Transferee succeeded to Landlord's
interest, (i) bound by any agreement amending, modifying or terminating the
Lease made without the Transferee's prior written consent prior to the time the
Transferee succeeded to Landlord's interest or (j) bound by any assignment of
the Lease or sublease of the Property, or any portion thereof, made prior to the
time the Transferee succeeded to Landlord's interest other than if pursuant to
the provisions of the Lease.

          4.   Notice to Tenant.  After notice is given to Tenant by Lender that
               ----------------
the Landlord is in default under the Note and the Mortgage and that the rentals
under the Lease should be paid to Lender pursuant to the terms of the assignment
of leases and rents executed and delivered by Landlord to Lender in connection
therewith, Tenant shall thereafter pay to Lender or as directed by the Lender,
all rentals and all other monies due or to become due to Landlord under the
Lease and Landlord hereby expressly authorizes Tenant to make such payments to
Lender and hereby releases and discharges Tenant from any liability to Landlord
on account of any such payments.

                                      G-3
<PAGE>

          5.   Lender's Consent.  If Tenant shall, without obtaining the prior
               ----------------
written consent of Lender, which consent shall not be unreasonably withheld (a)
enter into any agreement amending, modifying or terminating the Lease, (b)
prepay any of the rents, additional rents or other sums due under the Lease for
more than one (1) month in advance of the due dates thereof, (c) voluntarily
surrender the premises demised under the Lease or terminate the Lease without
cause or shorten the term thereof, or (d) assign the Lease or sublet the
premises demised under the Lease or any part thereof other than pursuant to the
provisions of the Lease, any such amendment, modification, termination,
prepayment, voluntary surrender, assignment or subletting, without Lender's
prior consent, shall not be binding upon Lender. Lender shall use its
commercially reasonable efforts to respond to any request for its consent or
approval within 15 days following a Request for Consent (as hereinafter
defined). For purposes of this Paragraph 5, a Request for Consent shall mean the
receipt by Lender of any information it reasonably requests in order to evaluate
the requested approval, including, but not limited to, financial information,
information concerning any assignee or subtenant and a copy of any written
agreement (in final form approved by all parties thereto) that is the subject of
its request for approval.

          6.   Lender to Receive Notices.  Tenant shall provide Lender with
               -------------------------
copies of all written notices sent to Landlord pursuant to the Lease
simultaneously with the transmission of such notices to the Landlord. Tenant
shall notify Lender of any default by Landlord under the Lease which would
entitle Tenant to cancel the Lease or to an abatement of the rents, additional
rents or other sums payable thereunder, and agrees that, notwithstanding any
provisions of the Lease to the contrary, no notice of cancellation thereof or,
except for abatements of rent pursuant to Section 6.3 or 11.3 or Article 12 of
the Lease, of such an abatement shall be effective unless Lender shall have
received notice of default giving rise to such cancellation or abatement and
shall have failed within sixty (60) days after receipt of such notice to cure
such default, or if such default cannot be cured within sixty (60) days, shall
have failed within sixty (60) days after receipt of such notice to commence and
thereafter diligently pursue any action necessary to cure such default, but in
no event more than ninety (90) days.

          7.   Notices.  All notices or other written communications hereunder
               -------
shall be deemed to have been properly given (i) upon delivery, if delivered in
person, (ii) one (1) Business Day (hereinafter defined) after having been
deposited for overnight delivery with any reputable overnight courier service,
or (iii) three (3) Business Days after having been deposited in any post office
or mail depository regularly maintained by the U.S. Postal Service and sent by
registered or certified mail, postage prepaid, return receipt requested,
addressed as follows:

If to Tenant:       CMGI, Inc.
                    100 Brickstone Square
                    Andover, Massachusetts 01810
                    Attention: General Counsel

With a copy to:     Hale and Dorr LLP
                    60 State Street
                    Boston, Massachusetts 02109
                    Attention: Pamela Coravos, Esq.

If to Lender:       Morgan Stanley Mortgage Capital Inc.
                    1585 Broadway
                    38/th/ Floor
                    New York, New York 10036
                    Attention: James Flaum & Kevin Swartz

                                      G-4
<PAGE>

With a copy to:     Cadwalader, Wickersham & Taft
                    100 Maiden Lane
                    New York, New York 10038
                    Attention: John Zizzo, Esq.

or addressed as such party may from time to time designate by written notice to
the other parties.  For purposes of this Section, the term "Business Day" shall
mean a day on which commercial banks are not authorized or required by law to
close in New York, New York.

Either party by notice to the other may designate additional or different
addresses for subsequent notices or communications.

          8.   Joint and Several Liability.  If Tenant consists of more than one
               ---------------------------
person, the obligations and liabilities of each such person hereunder shall be
joint and several. This Agreement shall be binding upon and inure to the benefit
of Lender and Tenant and their respective successors and assigns.

          9.   Definitions.  The term "Lender" as used herein shall include the
               -----------
successors and assigns of Lender and any person, party or entity which shall
become the owner of the Property by reason of a foreclosure of the Mortgage or
the acceptance of a deed or assignment in lieu of foreclosure or otherwise. The
term "Landlord" as used herein shall mean and include the present landlord under
the Lease and such landlord's predecessors and successors in interest under the
Lease, but shall not mean or include Lender. The term "Property" as used herein
shall mean the Property, the improvements now or hereafter located thereon and
the estates therein encumbered by the Mortgage.

          10.  No Oral Modifications.  This Agreement may not be modified in any
               ---------------------
manner or terminated except by an instrument in writing executed by the parties
hereto.

          11.  Governing Law.  This Agreement shall be deemed to be a contract
               -------------
entered into pursuant to the laws of the State where the Property is located and
shall in all respects be governed, construed, applied and enforced in accordance
with the laws of the State where the Property is located.

          12.  Inapplicable Provisions.  If any term, covenant or condition of
               -----------------------
this Agreement is held to be invalid, illegal or unenforceable in any respect,
this Agreement shall be construed without such provision.

          13.  Duplicate Originals; Counterparts.  This Agreement may be
               ---------------------------------
executed in any number of duplicate originals and each duplicate original shall
be deemed to be an original. This Agreement may be executed in several
counterparts, each of which counterparts shall be deemed an original instrument
and all of which together shall constitute a single Agreement. The failure of
any party hereto to execute this Agreement, or any counterpart hereof, shall not
relieve the other signatories from their obligations hereunder.

          14.  Number and Gender.  Whenever the context may require, any
               -----------------
pronouns used herein shall include the corresponding masculine, feminine or
neuter forms, and the singular form of nouns and pronouns shall include the
plural and vice versa.

          15.  Transfer of Loan.  Lender may sell, transfer and deliver the Note
               ----------------
and assign the Mortgage, this Agreement and the other documents executed in
connection therewith to one or more investors in the secondary mortgage market
("Investors").  In connection with such sale, Lender may retain or assign
responsibility for servicing the loan, including the Note, the Mortgage, this
Agreement and the other documents executed in connection therewith, or may
delegate some or all of such responsibility and/or obligations to a servicer
including, but not

                                      G-5
<PAGE>

limited to, any subservicer or master servicer, on behalf of the Investors. All
references to Lender herein shall refer to and include any such servicer to the
extent applicable.

          16.  Further Acts.  Tenant will, at the cost of Tenant, and without
               ------------
expense to Lender, do, execute, acknowledge and deliver all and every such
further acts and assurances as Lender shall, from time to time, reasonably
require, for the better assuring and confirming unto Lender the property and
rights hereby intended now or hereafter so to be, or for carrying out the
intention or facilitating the performance of the terms of this Agreement or for
filing, registering or recording this Agreement, or for complying with all
applicable laws.

          17.  Limitations on Lender's Liability. Tenant acknowledges that
               ---------------------------------
Lender is obligated only to Landlord to make the Loan upon the terms and subject
to the conditions set forth in the Loan Agreement. In no event shall Lender or
any purchaser of the Property at foreclosure sale or any grantee of the Property
named in a deed-in-lieu of foreclosure, nor any heir, legal representative,
successor, or assignee of Lender or any such purchaser or grantee (collectively
the Lender, such purchaser, grantee, heir, legal representative, successor or
assignee, the "Subsequent Landlord") have any personal liability for the
obligations of Landlord under the Lease and should the Subsequent Landlord
succeed to the interests of the Landlord under the Lease, Tenant shall look only
to the estate and property of any such Subsequent Landlord in the Property for
the satisfaction of Tenant's remedies for the collection of a judgment (or other
judicial process) requiring the payment of money in the event of any default by
any Subsequent Landlord as landlord under the Lease, and no other property or
assets of any Subsequent Landlord shall be subject to levy, execution or other
enforcement procedure for the satisfaction of Tenant's remedies under or with
respect to the Lease; provided, however, that the Tenant may exercise any other
right or remedy provided thereby or by law in the event of any failure by
Landlord to perform any such material obligation.

          IN WITNESS WHEREOF, Lender and Tenant have duly executed this
Agreement as of the date first above written.

                              LENDER:

                              Morgan Stanley Mortgage Capital Inc., a
                              New York corporation

                              By:_______________________________________________
                              Name:_____________________________________________
                              Title:____________________________________________

                              TENANT:

                              CMGI, Inc.
                              a Massachusetts corporation

                              By:_______________________________________________
                              Name:_____________________________________________
                              Title:____________________________________________

                                      G-6
<PAGE>

The undersigned accepts and agrees to
the provisions of Section 4 hereof:

LANDLORD:

TST 555/575 Market, L.L.C.,
a Delaware limited liability company

By:_____________________________________
Name:___________________________________
Title:__________________________________

                                      G-7
<PAGE>

                                ACKNOWLEDGMENTS

STATE OF CALIFORNIA           )
                              ) ss.
COUNTY OF ____________________)

          On _____________, before me, _____________, a Notary Public for the
State of California, personally appeared _____________, personally known to me
(or proved to me on the basis of satisfactory evidence) to be the person(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 authorized capacity(ies),
and that by his/her/their signature(s) on the instrument the person(s), or the
entity upon behalf of which the person(s) acted, executed the instrument.

WITNESS my hand and official seal.

_________________________________________________(SEAL)
                    (Signature)

STATE OF CALIFORNIA           )
                              ) ss.
COUNTY OF ____________________)

          On _____________, before me, _____________, a Notary Public for the
State of California, personally appeared _____________, personally known to me
(or proved to me on the basis of satisfactory evidence) to be the person(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 authorized capacity(ies),
and that by his/her/their signature(s) on the instrument the person(s), or the
entity upon behalf of which the person(s) acted, executed the instrument.

WITNESS my hand and official seal.

_________________________________________________(SEAL)
                    (Signature)

                                      G-8
<PAGE>

                                   EXHIBIT A
                                   ---------

                           (Description of Property)
                              (575 MARKET STREET)

That certain real property located in the City and County of San Francisco,
State of California, as follows:

          PARCEL ONE:
          ----------

          BEGINNING AT A POINT ON THE SOUTHEASTERLY LINE OF MARKET STREET,
DISTANT THEREON 190 FEET NORTHEASTERLY FROM THE NORTHEASTERLY LINE OF SECOND
STREET; RUNNING THENCE NORTHEASTERLY ALONG SAID SOUTHEASTERLY LINE OF MARKET
STREET, 100 FEET AND 6 INCHES; THENCE AT A RIGHT ANGLE, SOUTHEASTERLY 155 FEET
AND 1-1/4 INCHES TO THE NORTHWESTERLY LINE OF STEVENSON STREET; THENCE AT A
RIGHT ANGLE, SOUTHWESTERLY ALONG SAID LINE OF STEVENSON STREET, 100 FEET AND 6
INCHES; THENCE AT A RIGHT ANGLE, NORTHWESTERLY 155 FEET AND 1-1/4 INCHES TO THE
POINT OF BEGINNING.

          BEING A PORTION OF 100 VARA BLOCK NO. 346.

          PARCEL TWO:
          ----------

          NON-EXCLUSIVE PERPETUAL EASEMENTS APPURTENANT TO PARCEL THREE FOR
LIGHT AND AIR, FOR OVERHANGING LEDGES, BALCONIES AND OTHER ARCHITECTURAL
APPURTENANCES AND PROJECTIONS AND FOR FOUNDATION STRUCTURES, OVER, ACROSS, UPON
AND UNDER THE PARCEL DESCRIBED AS FOLLOWS:

          BEGINNING AT A POINT ON THE SOUTHEASTERLY LINE OF MARKET STREET,
DISTANT THEREON 290 FEET AND 6 INCHES NORTHEASTERLY FROM THE NORTHEASTERLY LINE
OF SECOND STREET; THENCE NORTHEASTERLY ALONG SAID SOUTHEASTERLY LINE OF MARKET
STREET, 15 FEET; THENCE AT A RIGHT ANGLE SOUTHEASTERLY, 155 FEET AND 1-1/4
INCHES TO THE NORTHWESTERLY LINE OF STEVENSON STREET; THENCE AT A RIGHT ANGLE
SOUTHWESTERLY AND ALONG SAID LINE OF STEVENSON STREET, 15 FEET; THENCE AT A
RIGHT ANGLE NORTHWESTERLY 155 FEET AND 1-1/4 INCHES TO THE POINT OF BEGINNING.

          LOT 58, BLOCK 3708

                                      G-9

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00016-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00016-of-00352.parquet"}]]