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                                                                  EXHIBIT 10.7.1

                                   SUBLEASE

     THIS SUBLEASE ("Sublease"), dated as of March 4, 1999, for reference
purposes only, is entered into by and between THE DIALOG CORPORATION, a Delaware
corporation, formerly Dialog Information Services, Inc., a California
corporation ("Sublessor"), and ANNUNCIO SOFTWARE, INC., a California corporation
("Sublessee").

                                    RECITALS

     A.  Sublessor leased certain premises ("Premises") including a building
containing approximately one hundred thirty three thousand, five hundred
(133,500) square feet (the "Building") located at the address commonly known as
2440 El Camino Real, Mountain View, California, pursuant to a certain Lease
between Sublessor, as Tenant, and Sobrato Development Companies #850, a
California limited partnership (hereinafter "Master Lessor"), as Landlord, dated
March 10, 1994 (as may be amended or otherwise modified from time to time, the
"Master Lease"), a copy of which Master Lease is attached hereto as EXHIBIT A.
Capitalized terms herein not otherwise defined herein shall have the same
meanings as provided in the Master Lease.

     B.  Sublessor desires to sublease to Sublessee, and Sublessee desires to
sublease from Sublessor, a portion of the Premises upon the terms and conditions
provided for herein.

     NOW, THEREFORE, in consideration of the mutual covenants and conditions
contained herein, Sublessor and Sublessee covenant and agree as follows:

                                   AGREEMENT

     1.  SUBLEASED PREMISES.

         (A) Subject to the terms and conditions set forth herein, Sublessor
hereby subleases to Sublessee, and Sublessee hereby subleases from Sublessor,
twenty-one thousand four hundred ninety-four (21,494) rentable square feet. Such
square footage includes space located on the third floor of the Building (the
"Subleased Premises"), as well as the nonexclusive right to use, in common with
Sublessor and other tenants of the building, the Common Use Areas (as defined
below). The Subleased Premises are more particularly described in EXHIBIT B
attached hereto.

         (B) Sublessee and Sublessor hereby agree that the calculation of the
rentable square footage of the Subleased Premises includes an equitable
apportionment made by Sublessor based upon Sublessee's Pro-Rata Share (as
hereinafter defined), attributable to Sublessor's right to non-exclusive usage
of the Common Use Areas. "Common Use Areas" shall mean those areas located on
the first floor of the Building and designated as such on EXHIBIT C, which
Common Use Areas consist of a lobby area, cafeteria, locker rooms, rest rooms
and conference rooms. Sublessor and Sublessee hereby agree that Sublessor's
determination of the rentable square footage of the Premises, as set forth
herein, shall be conclusive for the purpose of this Sublease.
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          (c) Sublessee shall provide Sublessor with reasonable prior written
notice requesting use of any of the conference rooms comprising the Common Use
Areas. Sublessor and Sublessor shall work in good faith to establish a schedule
of use of such conference rooms mutually acceptable to all parties possessing
the right to non-exclusive use of such conference rooms.

     2.   TERM.

          (A) The term of this Sublease (the "Term") shall commence upon
Sublessor's delivery of possession of the Subleased Premises to Sublessee (the
"Commencement Date").

          (B) Notwithstanding said Commencement Date, if for any reason
Sublessor cannot deliver possession of the Subleased Premises to Sublessee on or
before said date, Sublessor shall not be subject to any liability therefor, nor
shall such failure affect the validity of this Sublease or the obligations of
Sublessee hereunder or extend the term hereof, but in such case Sublessee shall
not be obligated to pay Rent (as hereinafter defined) or otherwise be liable to
Sublessor until possession of the Subleased Premises is tendered to Sublessee.
Sublessor shall use reasonable efforts to deliver the Subleased Premises to
Sublessee on or before the Commencement Date.

          (C) The Term of this Sublease shall end on January 8, 2005 (the
"Expiration Date"), unless earlier terminated in accordance with the terms of
this Sublease.

     3.   RENT.

          (A) Throughout the Term of this Sublease, Sublessee shall pay monthly
rent ("Rent") to Sublessor, which Rent is comprised of Basic Rent (as
hereinafter defined) and Additional Rent (as hereinafter defined), in the
following amounts:

              (I)  Commencing on the later of (A) the thirtieth (30 the) day
following the Commencement Date and (B) the date upon which Tenant substantially
completes Sublessee's Initial Improvements and receives a certificate of
occupancy for the Subleased Premises, but in no event later than April 15, 1999,
Sublessee shall pay Sublessor an initial monthly basic rent ("Basic Rent") for
the Subleased Premises in the amount of Two and 35/100 Dollars ($2.35) per
rentable square foot. During the Term of this Sublease, the monthly Basic Rent
shall increase annually in accordance with the following schedule:


                               Monthly Basic Rent
     Month of Sublease Term    Per Rentable Square Foot
     ------------------        -----------------------
      1-12                     $2.35
     13-24                     $2.65
     25-36                     $2.90
     37-48                     $3.00
     49-60                     $3.10
     61-expiration             $3.20

              (II) In addition to Basic Rent, commencing upon the Commencement
Date, Sublessee shall pay to Sublessor as additional rent ("Additional Rent")
Sublessee's pro rata
<PAGE>

share ("Sublessee's Pro-Rata Share") of expenses incurred by Sublessor with
respect to operating expenses for the Premises (including, without limitation,
costs incurred for utilities, building security and janitorial services), common
area maintenance costs, taxes and assessments, costs of insurance procured by
Master Lessor or Sublessor pursuant to Paragraph 12 of the Master Lease, and any
and all additional expenses payable by Sublessor to Master Lessor pursuant to
the Master Lease. Except to the extent included in Sublessee's pro rata share of
expenses payable by Sublessor to Master Lessor pursuant to the Master Lease,
"Additional Rent" shall not include and Sublessee shall not have any obligation
to pay for the following: (a) costs occasioned by the gross negligence, willful
misconduct or violation of any law by Sublessor or any other occupant of the
Premises (other than Sublessee) or their respective agents, employees or
contractors; (b) costs to correct any construction defect in the Premises or to
remedy any violation of any CC&Rs or law applicable to the Premises, which
violation exists on the Commencement Date; (c) leasing commissions; (d) costs of
any renovation, improvement, painting or redecorating of any portion of the
Premises not made available for Sublessee's exclusive or non-exclusive use; (e)
costs incurred in connection with the presence of any toxic or hazardous
substances (including, without limitation, asbestos and "PCB's") which are now
or hereafter become regulated by any governmental authority or agency thereof
("Hazardous Materials"), except to the extent caused by Sublessee or its agents,
employees, contractors or invitees; (f) interest, charges and fees incurred on
Sublessor's debt; and (g) costs which could properly be capitalized under
generally accepted accounting principles, except to the extent amortized over
the useful life of the capital item in question. Sublessor and Sublessee hereby
agree that Sublessee's Pro-Rata Share shall be the quotient derived by dividing
the number of rentable square feet of the Subleased Premises by 133,500. To the
extent that Sublessor notifies Sublessee that any items constituting Additional
Rent are due and payable under the Master Lease on a monthly basis, such
Additional Rent shall be paid by Sublessee to Sublessor as and when Basic Rent
is paid. To the extent that such items constituting Additional Rent are billed
from time to time to Sublessor by Master Lessor, such Additional Rent shall be
paid by Sublessee to Sublessor within seven (7) days after Sublessee's receipt
from Sublessor of an invoice therefor, and Sublessor shall thereupon promptly
remit such Additional Rent to Master Lessor. Notwithstanding the foregoing,
Sublessee shall not be required to pay any Additional Rent or perform any
obligation that is (i) fairly allocable to any period of time prior to the
Commencement Date or to any period after the expiration or sooner termination of
this Sublease or (ii) payable as a result of a default by Sublessor of any of
its obligations under the Master Lease, which default is not caused by
Sublessee. In addition, Sublessee shall not be required to pay for any portion
of taxes set forth in Paragraph 13 of the Master Lease levied or assessed on (i)
the value of any leasehold improvements, alterations or additions made by or for
the account of Sublessor or (ii) the value of Sublessor's personal property
located on the Premises, unless such leasehold improvements, alterations,
additions or personal property are used for the benefit of, or available for the
non-exclusive use of, Sublessee.

          (B) Except that the first installment of Rent shall be paid upon
execution of this Sublease, Rent shall be payable to Sublessor in lawful money
of the United States, in advance, without prior notice, abatement, demand, or
offset, on or before the first day of each calendar month during the term
hereof. If any rental period does not constitute a full calendar month, then
Rent for that month shall be prorated on a daily basis based upon the calendar
month. All Rent shall be paid to Sublessor at the address specified for notice
to Sublessor in SECTION 22, below, or at such other place as Sublessor may
designate by notice to Sublessee.
<PAGE>

          (C) In the event of any damage, casualty, or condemnation affecting
the Subleased Premises, Rent payable by Sublessee shall be abated hereunder, but
only to the extent that rent under the Master Lease is abated.

     4.   SECURITY DEPOSIT.

          (A) Upon its execution of this Sublease, Sublessee shall deposit with
Sublessor, and shall maintain with Sublessor throughout the Term of this
Sublease, the sum of One Hundred and Fifty-Four Thousand Seven Hundred and
Fifty-Six and 80/100 Dollars ($154,756.80) as security for Sublessee's faithful
performance of Sublessee's obligations hereunder. Sublessor shall not be
required to keep said deposit separate from its general accounts, and no trust
relationship is created herein between Sublessor and Sublessee with respect to
said security deposit.

          (B) Notwithstanding the foregoing, Sublessee may, at its option,
substitute for the cash described in subparagraph (a) above, an original
irrevocable standby letter of credit (the "Letter of Credit") in the amount of
One Hundred and Fifty-Four Thousand Seven Hundred and Fifty-Six and 80/100
Dollars ($154,756.80), which Sublessor may draw upon to cure any default under
this Sublease continuing beyond any applicable notice and cure periods or to
compensate Sublessor for any damage Sublessor incurs as a result of Sublessee's
failure to perform any of its obligations under this Sublease, which failure
continues beyond any applicable notice and cure periods. The Letter of Credit
shall (i) be issued by a major commercial bank reasonably acceptable to
Sublessor, (ii) have an expiration date one year following its issue, to be
automatically renewed annually throughout the term of the Sublease for a period
of not less than one year (unless Sublessor receives written notice of non-
renewal from the issurer of the Letter of Credit at least thirty (30) days prior
to the expiration date), (iii) provide for payment to Sublessor upon the
issuer's receipt of a sight draft from Sublessor together with Sublessor's
certificate certifying that a default has occurred and continued beyond any
applicable notice and cure periods under this Sublease and that the requested
sum is due and payable from Sublessee, and with no other conditions, (iv) be
transferable by Sublessor without cost, and (v) otherwise be in form and content
reasonably satisfactory to Sublessor's counsel. If Sublessor draws on the Letter
of Credit pursuant to the terms hereof, within ten (10) days of such draw,
Sublessee shall replenish the Letter of Credit or provide Sublessor with an
additional letter of credit conforming to the requirements of this Paragraph so
that the amount available to Sublessor from the Letter of Credit(s) provided
hereunder is the amount specified above. Sublessee's failure to deliver any
replacement, additional or extension of the Letter of Credit, or evidence of
renewal of the Letter of Credit, within the time specified herein shall
constitute an Event of Default under this Sublease and shall entitle Sublessor
to draw the full amount of the Letter of Credit then in effect.

          (C) If Sublessee fails to pay rent or other charges due hereunder, or
otherwise defaults with respect to any provision of this Sublease beyond any
applicable notice and cure periods, Sublessor may use, apply, or retain all or
any portion of said deposit for the payment of any rent or other charge in
default or for the payment of any sum to which Sublessor may become obligated by
reason of Sublessee's default, or to compensate Sublessor for any loss or damage
which Sublessor may suffer thereby. If Sublessor so uses or applies all or any
portion of said deposit, Sublessee shall within ten (10) days after written
demand therefor deposit cash with
<PAGE>

Sublessor in an amount sufficient to restore said deposit to the full amount
hereinabove stated and Sublessee's failure to do so shall be a material breach
of this Sublease.

          (D) If Sublessee performs all of Sublessee's obligations hereunder,
said security deposit, or so much thereof as has not theretofore been applied by
Sublessor, shall be returned, without payment of interest or other increment for
its use to Sublessee (or, at Sublessor's option, to the last permitted assignee,
if any, of Sublessee's interest hereunder) at the expiration of the term hereof
and after Sublessee has vacated the Subleased Premises.

     5.   IMPROVEMENTS/CONDITION OF SUBLEASED PREMISES.

          (A) Sublessor shall deliver the Subleased Premises to Sublessee in its
"as-is" condition, provided, that as of the Commencement Date, the roof and the
building systems servicing the Subleased Premises (including HVAC, mechanical
and plumbing) shall be in good working order and repair. Sublessor shall have no
obligation to make any alterations or improvements to the Subleased Premises.

          (B) Sublessee has used due diligence in inspecting the Subleased
Premises and, subject to subparagraph (a) above, agrees to accept the Subleased
Premises in "as-is" condition and with all faults as of the date of Sublessee's
execution of this Sublease, without any representation or warranty of any kind
or nature whatsoever, or any obligation on the part of Sublessor to modify,
improve or otherwise prepare the Subleased Premises for Sublessee's occupancy.

          (C) Sublessee shall be permitted, at its sole cost, to cause
Sublessee's Initial Improvements (as defined in EXHIBIT E) to be constructed in
the Subleased Premises, provided that Sublessee shall obtain the prior written
consent of Sublessor to the same and shall comply with both this Sublease
(including, without limitation, EXHIBIT E hereto) and the Master Lease with
regard to such improvements, including, without limitation, (i) obtaining the
consent of Master Lessor with regard thereto, and (ii) either removing or
surrending Sublessee's Initial Improvements with the Subleased Premises at the
expiration of this Sublease, as the case may be, in strict accordance with
Master Lessor's direction: In connection with Sublessee's construction of
Sublessee's Initial Improvements, Sublessor shall provide to Sublessee the
Sublessee Improvement Allowance in accordance with the terms of EXHIBIT E.

     6.   MASTER LEASE.

          (A) This Sublease shall be subject and subordinate to all of the terms
and provisions of the Master Lease, and Master Lessor shall have all rights in
respect of the Master Lease and the Subleased Premises as set forth therein.
Except for payments of rent required under the Master Lease (which payments
shall be made by Sublessor), and, except as otherwise provided herein, Sublessee
hereby assumes and agrees to perform for Sublessor's benefit, during the term of
this Sublease, all of Sublessor's obligations under the Master Lease insofar as
they relate to the Subleased Premises (hereinafter the "Assumed Obligations"),
which accrue during the term of this Sublease.

          (B) Sublessee shall fully perform all of the Assumed Obligations and
shall indemnify, defend, protect, and hold harmless Sublessor and Master Lessor
from any and all
<PAGE>

liability, damages, liabilities, claims proceedings, actions, demands and costs
(including reasonable attorneys' fees) resulting, directly or indirectly, from
Sublessee's failure to perform the Assumed Obligations.

     7.   INCORPORATION OF MASTER LEASE.

          (A) Except as otherwise provided in this Sublease, all of the terms
and provisions of the Master Lease are incorporated into and made a part of this
Sublease, and the rights and obligations of the parties under the Master Lease
are hereby imposed upon the parties hereto with respect to the Subleased
Premises, the Sublessor being substituted for the "Landlord" in the Master
Lease, the Sublessee being substituted for the "Tenant" in the Master Lease, the
Subleased Premises being substituted for "Premises" in the Master Lease, and
"Sublease" being substituted for "Lease" in the Master Lease.

          (B) Wherever there are time limits contained in the Master Lease (i)
calling or allowing for the service of notice by the "Tenant" thereunder, (ii)
pertaining to events of default by the "Tenant" thereunder, or (iii) within
which the "Tenant" thereunder must perform any act or observe any term, covenant
or condition thereunder, the same shall be deemed amended for the purposes of
this Sublease to provide for time limits of two (2) days less than those
provided for in the Master Lease.

          (C) Notwithstanding the foregoing, the following paragraphs of the
Master Lease are not incorporated herein: Paragraphs 1 and 2.F., the first three
sentences of Paragraph 3, the second sentence of Paragraph 4, Paragraph 5, the
third sentence of Paragraph 6, Paragraph 7, the first through third sentences of
Paragraph 8, the first two sentences of Paragraph 10, the first two sentences of
Paragraph 11(b), the final sentence of Paragraph 11(c), Paragraph 14, Paragraphs
18D, 26 and 31, the second full paragraph of Paragraph 32 and Paragraphs 37, 38,
40, 41, 44 and 45.

          (D) For the purposes of incorporating the terms and provisions of the
Master Lease into this Sublease, the following changes to the Master Lease terms
shall apply to this Sublease (references are to Paragraphs of the Master Lease):

     PARAGRAPH      COMMENTS/AMENDMENTS

     3              Sublessee shall be responsible for payment of Sublessee's
                    Pro-Rata Share (rather than 100%) of fixed and variable
                    costs associated with the garage.

     4              Notwithstanding anything to the contrary in Paragraph 4,
                    Sublessee shall not be permitted to use the Subleased
                    Premises for light manufacturing purposes.

     11.A.          Notwithstanding anything to the contrary in Paragraph 11.A.,
                    Sublessee shall be obligated, at its sole cost, to keep and
                    maintain, repair and replace the interior of the Subleased
                    Premises in the condition required thereunder. Sublessor
                    shall keep and maintain, repair and replace the exterior of
                    the Subleased Premises, the building operating systems, roof
                    and the common areas of the Building as required under the
                    Master Lease,
<PAGE>

                    shall maintain the service contracts required under
                    Paragraph 11.A. and shall pay all amounts required to be
                    paid to Master Lessor pursuant to Paragraphs 11.B. and 11.C.
                    of the Master Lease, and Sublessor shall charge Sublessee's
                    Pro-Rata Share of all such costs to Sublessee as Additional
                    Rent.

     12.C.          Sublessee shall name the Master Lessor and Sublessor as
                    additional insureds on any and all insurance policies that
                    are required under the Master Lease.

          (E) Notwithstanding the foregoing, Sublessee hereby agrees to waive,
release, indemnify, defend and hold Master Lessor and Sublessor harmless to the
same extent as Sublessor waives, releases, indemnifies and holds Master Lessor
harmless pursuant to the Master Lease.

     8.   SUBLESSOR'S OBLIGATIONS.

          (A) Except as expressly otherwise provided herein, Sublessor shall
have no obligation to Sublessee with respect to the Subleased Premises or the
performance by Master Lessor of any obligations of Master Lessor under the
Master Lease. Sublessee understands and recognizes that certain services are
required to be performed by Master Lessor under the Master Lease. Sublessee
shall not seek nor require Sublessor to perform any of such services, nor shall
Sublessee make any claim upon Sublessor for any damages which may arise by
reason of any breach or negligence, whether by omission or commission, by Master
Lessor or its agents in the performance (or nonperformance) of such services.
Notwithstanding the incorporation hereunder of certain provisions of the Master
Lease, including, without limitation, Paragraphs 11, 12(B) and 28, Sublessor
does not assume the obligations of Master Lessor under the Master Lease, but
agrees that, if and to the extent that the Master Lease requires Master Lessor
to provide utilities, insurance, maintenance, repairs, rebuilding, upgrading or
any other services in connection with the operation of the Subleased Premises,
Sublessee may notify Sublessor of any failure of Master Lessor to provide such
services and Sublessor shall thereafter use commercially reasonable efforts to
enforce Sublessor's rights under the Master Lease for the benefit of Sublessee,
provided that Sublessor shall not be required to incur any material costs or
expenses in connection therewith. Sublessee hereby expressly waives all rights
to make repairs at the expense of Sublessor or Master Lessor as provided by
statute or otherwise.

     9.   CONSENT OF MASTER LESSOR. If Sublessee desires to take any
action which requires the consent of Master Lessor pursuant to the terms of the
Master Lease, including, without limitation, the making of alterations or the
possession of Hazardous Materials, then, notwithstanding anything to the
contrary herein, (a) Sublessor, independently, shall have the same rights of
approval or disapproval as Master Lessor has under the Master Lease, and (b)
Sublessee shall not take any such action until it obtains the consent of both
Sublessor and Master Lessor, and (c) Sublessee shall request that Sublessor
obtain Master Lessor's consent on Sublessee's behalf, unless Sublessor and
Master Lessor agree that Sublessee may contact Master Lessor directly with
respect to the specific action for which Master Lessor's consent is required.
Any consent required of Sublessor conclusively shall be deemed reasonably
withheld, if consent also is required of the Master Lessor, and Master Lessor
withholds Master Lessor's consent.
<PAGE>

     10.  INDEMNITY. Except to the extent of any negligence or willful
misconduct of Sublessor or its agents or contractors or any breach by Sublessor
of Sublessor's obligations under this Sublease or the Master Lease, Sublessee
shall indemnify, defend, protect, and hold Sublessor harmless from and against
all actions, claims, demands, costs, liabilities, losses, reasonable attorneys'
fees, damages, penalties, and expenses (collectively "Claims") which may be
brought or made against Sublessor or which Sublessor may pay or incur to the
extent caused by (i) a breach of this Sublease or the Master Lease by Sublessee,
(ii) any violation of law by Sublessee or its employees, agents, contractors or
invitees (collectively, "Agents") relating to the use or occupancy of the
Subleased Premises or the Premises, (iii) any act or omission by Sublessee or
its Agents resulting in contamination of any part or all of the Subleased
Premises or the Premises by any Hazardous Materials, or (iv) the negligence or
willful misconduct of Sublessee or its Agents. In addition, except to the extent
of any negligence or willful misconduct of Master Lessor or its agents or
contractors or any breach by Master Lessor of Master Lessor's obligations under
the Master Lease, Sublessee shall indemnify, defend, protect, and hold Master
Lessor harmless from and against all Claims which may be brought or made against
Master Lessor or which Master Lessor may pay or incur to the extent caused by
(A) a breach of this Sublease or the Master Lease by Sublessee, (B) any
violation of law by Sublessee or its Agents relating to the use or occupancy of
the Subleased Premises or the Premises, (C) any act or omission by Sublessee or
its Agents resulting in contamination of any part or all of the Subleased
Premises or the Premises by any Hazardous Materials, or (D) the negligence or
willful misconduct of Sublessee or its Agents.

     11.  ASSIGNMENT AND SUBLETTING. Sublessee shall have the right to assign
this Sublease or sublet all or a portion of the Subleased Premises with the
prior written consent of both Sublessor and Master Lessor, in accordance with
the terms of the Master Lease and this Sublease. Notwithstanding any of the
foregoing, in the event that Sublessee wishes to assign this Sublease or sub-
sublease any portion of the Subleased Premises (except in connection with a
permitted transfer described in Paragraph 29.E. of the Master Lease) for a
period which will leave three months or less remaining on the Term of this
Sublease after the expiration of the proposed sub-sublease, Sublessee shall
provide Sublessor with written notice of Sublessee's desire to assign this
Sublease or sub-sublease such portion of the Subleased Premises for such period
of time prior to engaging in any efforts to market the same. Following
Sublessor's receipt of such notice, Sublessor shall have ten (10) days in which
it may elect to terminate this Sublease with respect to the space described in
Sublessee's notice (in the case of termination as to a portion of the Subleased
Premises, Sublessee's obligations under the Sublease as to the balance of the
Subleased Premises remaining shall be proportionately reduced). In the event
that Sublessor fails to timely exercise such right of recapture, Sublessee shall
have the right to market the Sublease for assignment or such portion of the
Subleased Premises for sub-sublease. Following Sublessor's receipt of all
agreements, statements and additional required information in connection with
any proposed assignment or sub-sublease, Sublessor shall have a period of ten
(10) business days within which to notify Sublessee in writing that the
Sublessor elects (i) to permit Sublessee to assign/sublet such space to the
named assignee/subtenant on the terms and conditions set forth in the notice or
(ii) to refuse consent. Sublessor agrees that Sublessor's consent with respect
thereto shall not be unreasonably withheld, conditioned or delayed, provided
that Sublessor's consent shall conclusively be deemed reasonably withheld, if
consent also is required of Master Lessor, and Master Lessor withholds such
consent.
<PAGE>

     12.  EARLY TERMINATION. Upon any termination of the Master Lease, this
Sublease shall also terminate, and, upon such termination, Sublessor shall
return to Sublessee any amounts of the security deposit which have not otherwise
been applied and any amounts prepaid by Sublessee to Sublessor which have not
been credited towards the payment of rent or other expenses; provided, however,
that if, without the fault of Sublessor hereunder, the Master Lease should
terminate prior to the expiration of this Sublease, Sublessor shall have no
liability to Sublessee on account of such termination. To the extent the Master
Lease grants Sublessor any discretionary rights to terminate the Master Lease,
whether due to casualty, cancellation, or otherwise, Sublessor shall be entitled
to exercise or not exercise such right in its sole discretion. Other than
pursuant to rights expressly granted in the Master Lease, Sublessor shall not
enter into any amendment of the Master Lease with respect to the Subleased
Premises that would terminate the Master Lease or otherwise materially diminish
Sublessee's rights or materially increase Sublessee's obligations hereunder
without Sublessee's prior written consent.

     13.  SURRENDER OF SUBLEASED PREMISES. Upon the expiration or earlier
termination of this Sublease, Sublessee shall surrender the Subleased Premises
in the condition existing as of the Commencement Date, reasonable wear and tear
and damage by event of casualty and by Hazardous Materials not caused by
Sublessee excepted.

     14.  SIGNAGE. Sublessee shall not place or permit to be placed, in, upon,
or about the Building any signs or advertisements not approved by Sublessor in
its sole discretion. Sublessor agrees to provide, at its sole cost, signage for
Sublessee in the garage, on the ground floor and on the third floor of the
Building, as well as on the Building's monument sign located on El Camino Real.

     15.  PARKING. Sublessee shall be entitled to the non exclusive and
unassigned use of 3.2 parking spaces per 1,000 rentable square feet of leased
space. Sublessee shall not be charged for the use of such parking spaces
throughout the Term.

     16.  UTILITIES. Sublessor shall provide heating and air conditioning to the
Subleased Premises during the following standard building hours of operation:
6:00 a.m. to 6:00 p.m., Monday through Friday; 7:00 a.m. to 3:00 p.m., Saturday
and Sunday. In addition, Sublessor shall provide, upon at least one business
day's notice from Sublessee, heating and air conditioning during hours outside
of standard building hours, and Sublessee shall reimburse Sublessor for the
costs actually incurred by Sublessor in providing such services. The cost of all
utilities serving the Subleased Premises shall be passed through to Sublessee as
Additional Rent, to the extent any such utility is not being directly provided
to Sublessee by the utility company. Sublessor reserves the right to cause to be
installed meters to separately monitor the utility usage of individual tenants.
If Sublessor has meters so installed, then the cost passed through to tenants
shall not be a pro-rata allocation, but shall be based upon actual consumption.
Sublessor shall not be liable for a loss of or injury to property, however
occurring, through or in connection with or incidental to furnishing or failure
to furnish any utilities to the Subleased Premises, and Sublessee shall not be
entitled to abatement or reduction of any portion of Rent as a result thereof.
<PAGE>

     17.  EXPANSION.

          (A) On the twenty-fifth month of the Term of this Sublease (the "Fifth
Floor Expansion Date"), the Subleased Premises as defined herein shall be
increased to include the eleven thousand four hundred and eighty-six (11,486)
rentable square feet located on the fifth floor of the Building and outlined on
EXHIBIT D hereto (the "Fifth Floor Expansion Space"), for a total rentable
square footage of thirty-two thousand nine hundred and eighty (32,980) rentable
square feet.

          (B) Sublessee's sublease of the Fifth Floor Expansion Space shall be
on the terms and conditions set forth in this Sublease, except that the initial
Basic Rent for the Fifth Floor Expansion Space shall be in the amount of Two and
80/100 Dollars ($2.80) per rentable square foot of the Fifth Floor Expansion
Space. On the first anniversary of the Fifth Floor Expansion Date, the monthly
Basic Rent for the Fifth Floor Expansion Space shall increase to a monthly basic
rent of Two and 90/100 Dollars ($2.90) per rentable square foot of the Fifth
Floor Expansion Space. On the second anniversary of the Fifth Floor Expansion
Date, the monthly Basic Rent for the Fifth Floor Expansion Space shall increase
to a monthly basic rent of Three Dollars ($3.00) per rentable square foot of the
Fifth Floor Expansion Space. On the third anniversary of the Fifth Floor
Expansion Date, the monthly Basic Rent for the Fifth Floor Expansion Space shall
increase to a monthly basic rent of Three and 10/100 Dollars ($3.10) per
rentable square foot of the Fifth Floor Expansion Space.

          (C) Upon the Fifth Floor Expansion Date,' Sublessee's Pro-Rata Share
of Additional Rent payable with respect to the Subleased Premises will be
increased, based on the additional square footage added.

          (D) Upon the Fifth Floor Expansion Date, Sublessee shall be provided a
tenant improvement allowance in an amount of up to Five Dollars ($5.00) per
rentable square foot of the Fifth Floor Expansion Space, which allowance shall
be paid by Sublessor to Sublessee towards the construction of tenant
improvements in the Fifth Floor Expansion Space upon the satisfaction of the
requirements set forth in, and in accordance with the terms of, EXHIBIT E.

     18.  NO THIRD PARTY RIGHTS. The benefit of the provisions of this Sublease
is expressly limited to Sublessor and Sublessee. Under no circumstances will any
third party be construed to have any rights as a third party beneficiary with
respect to any of said provisions; provided, however, that Master Lessor shall
be entitled to the benefit of Sublessee's (a) assumption of Sublessor's
obligations, as "Tenant" under the Master Lease, pursuant to Section 6 above,
and (b) indemnities set forth in this Sublease.

     19.  CONFLICTS. In the event of any conflict between the incorporated
provisions of the Master Lease and the Sublease, the provisions of this Sublease
shall govern and control.

     20.  BROKERAGE. Each party warrants and represents to the other that such
party has not retained the services of any real estate broker, finder or any
other person whose services would form the basis for any claim for any
commission or fee in connection with this Sublease or the transactions
contemplated hereby, except for the following parties: Sublessor represents that
it has retained CB Richard Ellis ("CB"), and Sublessee represents that it has
retained Wayne
<PAGE>

Mascia Associates ("WMA"). Sublessor shall pay directly to CB its fees due on
account hereof, in accordance with its listing agreement. WMA shall look solely
to CB for payment of its commission or fee in connection with this Sublease.
Each party agrees to save, defend, indemnify and hold the other party free and
harmless from any breach of its warranty and representation as set forth in this
paragraph, including the other party's reasonable attorneys' fees.

     21.  HAZARDOUS MATERIALS. To the actual knowledge of Sublessor, without any
duty of inquiry or examination, no Hazardous Materials exist on the Premises or
the soil, surface water or groundwater thereof in violation of any laws or
regulations governing Hazardous Materials. Sublessee shall have no liability to
Sublessor under this Sublease for the presence of any Hazardous Materials on or
about the Premises, which presence is not at all caused or contributed to by
Sublessee or its Agents.

     22.  NOTICES.

          (A)  Notices and other communications hereunder shall be in writing
and shall be given or made by personal delivery, certified mail or reputable
overnight courier addressed to the parties at their respective addresses set
forth below, or at any other address which either party may hereafter designate
for such purpose by a written notice; it being expressly understood that as of
the Commencement Date, all notices shall be sent to the following addresses:

               TO SUBLESSOR AT:  The Dialog Corporation
                                 11,000 Regency Parkway
                                 Suite 10
                                 Cary, NC 27511
                                 Attn: Denise Bryant, Esq.

               WITH COPY TO:     Cooley Godward LLP
                                 1 Maritime Plaza
                                 San Francisco, CA 94111
                                 Attn: Felice Liang

               TO SUBLESSEE AT:  (prior to the Commencement Date)
                                 Annuncio Software, Inc.
                                 5150 El Camino Real, Suite B31
                                 Los Altos, CA 94022
                                 Attn: Nancy Robertson

                                 (on and after the Commencement Date)
                                 At the Subleased Premises

Notices shall be deemed received on the date of actual delivery (or refusal to
accept delivery) as indicated on the return receipt or airbill.

     23.  SUBLESSOR DEFAULT. In the event that Sublessor defaults (through no
fault of Sublessee) in the performance or observance of any of Sublessor's
obligations under the Master
<PAGE>

Lease which obligations are not required to be performed by Sublessee hereunder
or fails to perform Sublessor's stated obligations under this Sublease, then
Sublessee shall give Sublessor notice specifying in what manner Sublessor has
defaulted, and if such default shall not be cured by Sublessor within thirty
(30) days thereafter (except that if such default cannot be cured within said
thirty (30) day period, this period shall be extended for an additional
reasonable time; provided that Sublessor commences to cure such default within
such thirty (30) day period and proceeds diligently thereafter to effect such
cure as quickly as possible), then Sublessee shall be entitled to cure such
default and promptly collect from Sublessor, Sublessee's reasonable expenses in
so doing (including, without limitation, reasonable attorneys' fees and court
costs), or, at Sublessee's option, to offset such reasonable expenses against
all future payments of rent and additional rent due under the Sublease.

     24.  REASONABLE EXPENDITURES. Any expenditure by a party permitted or
required under this Sublease, for which such party is entitled to demand and
does demand reimbursement from the other party, shall be reasonably incurred and
shall be substantiated by documentary evidence available for inspection and
review by the other party or its representative during normal business hours.

     25.  COUNTERPARTS. This Sublease may be executed in any number of
counterparts, each of which counterparts shall be deemed to be an original, and
all of which together shall constitute one and the same instrument.

     26.  EXHIBITS. All exhibits referred to in this Sublease are attached
hereto and incorporated herein by reference.

     27.  MASTER LESSOR CONSENT. This Sublease is subject to the consent of the
Master Lessor, pursuant to Paragraph 29 of the Master Lease.

     IN WITNESS WHEREOF, the parties have executed this Sublease as of the date
first written above.

THE DIALOG CORPORATION,                      ANNUNCIO SOFTWARE, INC.,
a Delaware corporation,                      a California corporation

formerly Dialog Information Services, Inc.

By: /s/ Victor Cohen                         By: /s/ DIDIER MORETTI
    ------------------------------               -------------------------------

Its: /s/ Director of Financial Op.           Its: President & CEO
    ------------------------------                ------------------------------

By: /s/ Denise Bryant                        By: /s/  MAURIZIO GIANOLA
    ------------------------------               -------------------------------

Its: Assoc. Corporate Counsel                Its: VP ENGINEERING.
    ------------------------------               -------------------------------
<PAGE>

10600 North De Anza Blvd.     408.446.0700
Suite 200                     Facsimile: 408.446.0583
Cupertino, CA 95014-2075      www.sobrato.com

                                                                         SOBRATO

                                                           DEVELOPMENT COMPANIES

                        LANDLORD'S CONSENT TO SUBLEASE

The Sobrato 1979 Trust, a California Limited Partnership, formerly Sobrato
Development Companies #850, a California Limited Partnership ("Landlord"), as
Landlord under that certain Lease (the "Lease") dated March 10, 1994 by and
between Landlord and The Dialog Corporation, a California corporation, formerly
Dialog Information Services, Inc., a California corporation ("Tenant"), as
Tenant, subject to and specifically conditioned upon the following terms and
conditions hereby grants its consent to the Sublease dated March 4, 1999 made by
and between the Tenant, as sublandlord, and Annuncio Software, Inc., a
California corporation ("Subtenant"), as subtenant, a copy of which is attached
as Exhibit A ("the Sublease"), covering that certain premises (the "Premises")
commonly known as 2440 El Camino Real, Mountain View, California.

As conditions to the consent of Landlord to the Sublease, it is understood and
agreed as follows:

1.  NO RELEASE. This Consent to Sublease shall in no way release the Tenant or
any person or entity claiming by, through or under Tenant, including Subtenant,
from any of its covenants, agreements, liabilities and duties under the Lease,
as the same may be amended from time to time, without respect to any provision
to the contrary in the Sublease.

2.  SPECIFIC PROVISIONS OF LEASE AND SUBLEASE. This Consent to Sublease
consenting to a sublease to Subtenant does not constitute approval by Landlord
of any of the provisions of the Sublease document or agreement thereto or
therewith; nor shall the same be construed to amend the Lease in any respect,
any purported modifications being solely for the purpose of setting forth the
rights and obligations as between Tenant and Subtenant, but not binding
Landlord. The Sublease is, in all respects, subject and subordinate to the
Lease, as the same may be amended. Furthermore, in the case of any conflict
between the provisions of this Consent to Sublease or the Lease and the
provisions of the Sublease, the provisions of this Consent to Sublease or the
Lease, as the case may be, shall prevail unaffected by the Sublease.

3.  LIMITED CONSENT. This Consent to Sublease does not and shall not be
construed or implied to be a consent to any other matter for which Landlord's
consent is required under the Lease, including, without limitation, any
Alterations under the Lease.

4.  TENANT'S CONTINUING LIABILITY. Tenant shall be liable to Landlord for any
default under the Lease, whether such default is caused by Tenant or Subtenant
or anyone claiming by or through either Tenant or Subtenant, but the foregoing
shall not be
<PAGE>

deemed to restrict or diminish any right which Landlord may have against
Subtenant pursuant to the Lease, in law or in equity for violation of the Lease
or otherwise, including, without limitation, the right to enjoin or otherwise
restrain any violation of the Lease by Subtenant.

5.   DEFAULT BY TENANT UNDER THE LEASE. If Tenant defaults under the Lease,
Landlord may elect to receive directly from Subtenant all sums due or payable to
Tenant by Subtenant pursuant to the Sublease. Upon written notice from Landlord,
Subtenant shall thereafter pay to Landlord any and all sums due or payable under
the Sublease. In such event, Tenant shall receive from Landlord a corresponding
credit for such sums against any payments then due or thereafter becoming due
from Tenant.

6.   TERMINATION OF LEASE. If at any time prior to the expiration of the term of
the Sublease the Lease shall terminate or be terminated for any reason, the
Sublease shall simultaneously terminate. However, Subtenant agrees, at the
election and upon written demand of Landlord, and not otherwise, to attorn to
Landlord for the remainder of the term of the Sublease, such attornment to be
upon all of the terms and conditions of the Lease, except that the Base Rent set
forth in the Sublease shall be substituted for the Base Rent set forth in the
Lease and the computation of Additional Rent as provided in the Lease shall be
modified as set forth in the Sublease. The foregoing provisions of this
paragraph shall apply notwithstanding that, as a matter of law, the Sublease may
otherwise terminate upon the termination of the Lease and shall be self-
operative upon such written demand of the Landlord, and no further instrument
shall be required to give effect to said provisions. Upon the demand of
Landlord, however, Subtenant agrees to execute, from time to time, documents in
confirmation of the foregoing provisions of this paragraph satisfactory to
Landlord in which Subtenant shall acknowledge such attornment and shall set
forth the terms and conditions of its tenancy.

7.   SUBLEASE PROFITS. Pursuant to Section 29 of the Lease, provided the
Sublease remains in full force and effect, Tenant agrees to pay to Landlord a
Profit Share defined in the attached Exhibit B and calculated in the attached
Scheduled 1.

8.   NO WAIVER; NO PRIVITY. Nothing herein contained shall be deemed a waiver of
any of the Landlord's rights under the Lease. In no event, however, shall
Landlord be deemed to be in privity of contract with Subtenant or owe any
obligation or duty to Subtenant under the Lease or otherwise, any duties of
Landlord under the Lease being in favor of, for the benefit of and enforceable
solely by Tenant.

9.   NOTICES. Subtenant agrees to promptly deliver a copy to Landlord of all
notices of default and all other notices sent to Tenant under the Sublease, and
Tenant agrees to promptly deliver a copy to Landlord of all such notices sent to
Subtenant under the Sublease. All copies of any such notices shall be delivered
personally or sent by United States registered or certified mail, postage
prepaid, return receipt requested, to Landlord.

LANDLORD
The Sobrato 1979 Trust, a California Limited Partnership

                                    Page 2
<PAGE>

by /s/ Signature Illegible
its

TENANT
The Dialog Corporation, a California corporation

by /s/ Victor Cohen
   --------------------------------
its Director of Finance Op.
    -------------------------------

SUBTENANT
Annuncio Software, Inc., a California corporation

by /s/ Didier Moretti
   --------------------------------
its DIDIER MORETTI
    -------------------------------

                                    Page 3
<PAGE>

                                  EXHIBIT "B"

                             SUBLEASE PROFIT SPLIT
<TABLE>
<CAPTION>
                  Dialog               Annuncio       Gross         Remaining            Fifty % share
                  ---------------      --------       -------       --------------       -------------
                  Rent (Prorated)      Rent           Profit        Sublease costs       Share
                  ---------------      --------       -------       --------------       -------------
<S>               <C>                  <C>            <C>           <C>                  <C>
                                                                       $511,432.78
March, 1999              $11,647       $ 21,182       $ 9,535          $   501,898             $     0
April                    $27,774       $ 50,511       $22,737          $   479,161             $     0
May                      $27,774       $ 50,511       $22,737          $   456,424             $     0
June                     $27,774       $ 50,511       $22,737          $   433,687             $     0
July                     $27,774       $ 50,511       $22,737          $   410,950             $     0
August                   $27,774       $ 50,511       $22,737          $   388,213             $     0
September                $27,774       $ 50,511       $22,737          $   365,476             $     0
October                  $27,774       $ 50,511       $22,737          $   342,739             $     0
November                 $27,774       $ 50,511       $22,737          $   320,002             $     0
December                 $27,774       $ 50,511       $22,737          $   297,265             $     0
January, 2000*           $27,774       $ 50,511       $22,737          $   274,528             $     0
February                 $27,774       $ 50,511       $22,737          $   251,791             $     0
March                    $27,774       $ 56,959       $29,185          $   222,606             $     0
April                    $27,774       $ 56,959       $29,185          $   193,421             $     0
May                      $27,774       $ 56,959       $29,185          $   164,236             $     0
June                     $27,774       $ 56,959       $29,185          $   135,051             $     0
July                     $27,774       $ 56,959       $29,185          $   105,867             $     0
August                   $27,774       $ 56,959       $29,185          $    76,682             $     0
September                $27,774       $ 56,959       $29,185          $    47,497             $     0
October                  $27,774       $ 56,959       $29,185          $    18,312             $ 5,437
November                 $27,774       $ 56,959       $29,185          $         0             $14,592
December                 $27,774       $ 56,959       $29,185          $         0             $14,592
January, 2001            $27,774       $ 56,959       $29,185          $         0             $14,592
February                 $27,774       $ 56,959       $29,185          $         0             $14,592
March                    $42,616       $ 94,493       $51,877          $         0             $25,939
April                    $42,616       $ 94,493       $51,877          $         0             $25,939
May                      $42,616       $ 94,493       $51,877          $         0             $25,939
June                     $42,616       $ 94,493       $51,877          $         0             $25,939
July                     $42,616       $ 94,493       $51,877          $         0             $25,939
August                   $42,616       $ 94,493       $51,877          $         0             $25,939
September                $42,616       $ 94,493       $51,877          $         0             $25,939
October                  $42,616       $ 94,493       $51,877          $         0             $25,939
November                 $42,616       $ 94,493       $51,877          $         0             $25,939
December                 $42,616       $ 94,493       $51,877          $         0             $25,939
January, 2002            $42,616       $ 94,493       $51,877          $         0             $25,939
February                 $42,616       $ 94,493       $51,877          $         0             $25,939
March                    $42,616       $ 97,791       $55,175          $         0             $27,588
April                    $42,616       $ 97,791       $55,175          $         0             $27,588
May                      $42,616       $ 97,791       $55,175          $         0             $27,588
June                     $42,616       $ 97,791       $55,175          $         0             $27,588
July                     $42,616       $ 97,791       $55,175          $         0             $27,588
August                   $42,616       $ 97,791       $55,175          $         0             $27,588
September                $42,616       $ 97,791       $55,175          $         0             $27,588
October                  $42,616       $ 97,791       $55,175          $         0             $27,588
November                 $42,616       $ 97,791       $55,175          $         0             $27,588
December                 $42,616       $ 97,791       $55,175          $         0             $27,588
January, 2003            $42,616       $ 97,791       $55,175          $         0             $27,588
February                 $42,616       $ 97,791       $55,175          $         0             $27,588
March                    $42,616       $101,089       $58,473          $         0             $29,237
April                    $42,616       $101,089       $58,473          $         0             $29,237
May                      $42,616       $101,089       $58,473          $         0             $29,237
June                     $42,616       $101,089       $58,473          $         0             $29,237
July                     $42,616       $101,089       $58,473          $         0             $29,237
August                   $42,616       $101,089       $58,473          $         0             $29,237
September                $42,616       $101,089       $58,473          $         0             $29,237
October                  $42,616       $101,089       $58,473          $         0             $29,237
November                 $42,616       $101,089       $58,473          $         0             $29,237
December                 $42,616       $101,089       $58,473          $         0             $29,237
January, 2004            $42,616       $101,089       $58,473          $         0             $29,237
February                 $42,616       $101,089       $58,473          $         0             $29,237
March                    $42,616       $104,387       $61,771          $         0             $30,886
</TABLE>
<PAGE>

<TABLE>
<S>                      <C>             <C>            <C>          <C>     <C>
April                    $42,616         $104,387       $61,771      $0      $30,886
May                      $42,616         $104,387       $61,771      $0      $30,886
June                     $42,616         $104,387       $61,771      $0      $30,886
July                     $42,616         $104,387       $61,771      $0      $30,886
August                   $42,616         $104,387       $61,771      $0      $30,886
September                $42,616         $104,387       $61,771      $0      $30,886
October                  $42,616         $104,387       $61,771      $0      $30,886
November                 $42,616         $104,387       $61,771      $0      $30,886
December                 $42,616         $104,387       $61,771      $0      $30,886
January, 2005            $42,616         $104,387       $61,771      $0      $30,886
February                 $42,616         $104,387       $61,771      $0      $30,886
</TABLE>

January 2000 CPI will be determined later, all profit splits from that date
forward are estimates.
<PAGE>

                                  EXHIBIT A

                                 MASTER LEASE


<PAGE>

                                 EXHIBIT A

                                LEASE BETWEEN
                    DIALOG INFORMATION SERVICES, INC., AND
                      SOBRATO DEVELOPMENT COMPANIES #850


Section                                                                  Page #
-------                                                                  ---- -
Parties 1
Definitions                                                                 1
       Parcel Map                                                           1
       Land                                                                 1
       Building                                                             1
       Common Area                                                          1
       Tenancy-In-Common Agreement                                          1
       Premises                                                             1
Premises                                                                    1
Use                                                                         1
Term and Rental                                                             2
       Rental Adjustment                                                    2
       Early Occupancy                                                      2
Late Charges                                                                2
Possession                                                                  3
Acceptance of Possession and Covenants to Surrender                         3
Uses Prohibited                                                             4
Alterations and Additions                                                   4
Maintenance of Premises                                                     4
       Tenant's Obligations                                                 4
       Landlord's Obligations                                               5
       Amortization of Certain Capital Replacements                         5
Hazard Insurance                                                            5
       Tenant's Use                                                         5
       Landlord's Insurance                                                 6
       Tenant's Insurance                                                   6
       Waiver                                                               6
Taxes                                                                       6
Utilities                                                                   7
Abandonment                                                                 7
Free From Liens                                                             7
Compliance With Governmental Regulations                                    7
Toxic Waste and Environmental Damage                                        7
       Tenant's Responsibility                                              7
       Tenant's Indemnity Regarding Hazardous Materials                     8
       Actual Release by Tenant                                             8
       Landlord's Indemnity Regarding Hazardous Materials                   9
       Environmental Monitoring                                             9
Indemnity                                                                   9
Advertisements and Signs                                                    10
Attorney's Fees                                                             10
Tenant's Default                                                            10
       Remedies                                                             10
       Right to Re-enter                                                    11
       Abandonment                                                          11
       No Termination                                                       11
Surrender of Lease                                                          11
This paragraph intentionally left blank                                     12
Landlord's Default                                                          12
Notices                                                                     12
<PAGE>

Entry by Landlord                                                           12
Destruction of Premises                                                     12
       Destruction by an Insured Casualty                                   12
       Destruction by an Uninsured Casualty                                 13
       Destruction during the Last Year of the Lease Term                   13
Assignment or Sublease                                                      13
       Consent by Landlord                                                  13
       Assignment or Subletting Consideration                               14
       No Release                                                           14
       Effect of Default                                                    14
       Permitted Transfers                                                  14
Condemnation                                                                14
Effects of Conveyance                                                       15
Subordination                                                               15
Waiver                                                                      15
Holding Over                                                                16
Successors and Assigns                                                      16
Estoppel Certificates                                                       16
Option to Extend the Lease Term                                             16
       Grant and Exercise of Option                                         16
       Determination of Fair Market Rental                                  17
       Resolution of a Disagreement over the Fair Market Rental             17
Options                                                                     18
Quiet Enjoyment                                                             18
Brokers                                                                     18
Landlord's Liability                                                        18
Authority of Parties                                                        18
Transportation Demand Management programs                                   18
Right Of First Offering To Purchase                                         18
Dispute Resolution                                                          19
Miscellaneous Provisions                                                    19
       Rent                                                                 19
       This paragraph intentionally left blank                              19
       Performance by Landlord                                              19
       Interest                                                             20
       Rights and Remedies                                                  20
       Survival of Indemnities                                              20
       Severability                                                         20
       Choice of Law                                                        20
       Time                                                                 20
       Entire Agreement                                                     20
       Representations                                                      20
       Headings                                                             20
       Exhibits                                                             20
Exhibit "A" - Parcel Map                                                    21
Exhibit "B" - Tenancy In Common and Maintenance Agreement                   22

                                    Page ii
<PAGE>

     1.  PARTIES: THIS LEASE, is entered into on this 10th day of MARCH 1994,
between SOBRATO DEVELOPMENT COMPANIES #850, a California Limited Partnership,
whose address is 10600 North De Anza Boulevard, Suite 200, Cupertino, CA 95014
and DIALOG INFORMATION SERVICES, INC., a California Corporation, whose address
is 3460 Hillview Avenue, Palo Alto, CA 94304, hereinafter called respectively
Landlord and Tenant.

     2.  DEFINITIONS:

         A.  PARCEL MAP. The term "Parcel Map" shall mean that certain
subdivision map entitled "Tract No. 7813 - Skyview" which map was filed for
record in the Office of the Recorder of Santa Clara County, California on the
10th day of June, 1986, Book 561, pages 1, 2, 3, and 4. Page 2 of the Parcel Map
is attached hereto as Exhibit "A"
                      -----------

         B.  LAND. The term "Land" shall mean that certain real property more
particularly described as Lot 1 on the Parcel Map.

         C.  BUILDING. The term "Building" shall mean that seven (7) story
concrete and steel building situated on the Land containing 133,500 square feet
and all interior improvements existing therein.

         D.  COMMON AREA. The term "Common Area" shall mean (i) the site area
surrounding the Building on Lot 1 and (ii) that certain real property beneath
Lot 1 described as Lot 2 on the Parcel Map consisting of a three (3) level
underground garage shared by Landlord as the owner of Lot 1 and the owners of
lots 3 through 7 inclusive.

         E.  TENANCY-IN-COMMON AGREEMENT. The term "Tenancy-In Common Agreement"
shall mean that certain Tenancy-In-Common and Maintenance Agreement, Declaration
of Covenants, Conditions and Restrictions and Grant of Easements recorded June
10, 1986 as amended September 8, 1986, attached hereto as Exhibit "B".
                                                          -----------

         F.  PREMISES. The term "Premises" shall mean (i) the Land; (ii) the
Building; and (iii) all of Landlord's rights with respect to the Common Area as
more particularly described in the Tenancy-In-Common Agreement.

     3.  PREMISES: Landlord hereby leases the Premises to Tenant, and Tenant
hires the Premises from Landlord. Landlord also hereby assigns to Tenant for the
term of this Lease all of Landlord's rights in and to the Common Area as the
owner of Lot 1 under the Tenancy in Common Agreement. Tenant shall perform the
duties of Landlord as the Managing Owner under such agreement until Lots 3
through 7 (the "Adjacent Properties") are developed at which time Landlord shall
resume the duties of the Managing Owner. Notwithstanding the terms of the
Tenancy in Common Agreement, Tenant shall be responsible for 100% of the
variable costs of maintaining the garage (e.g. sweeping, security, etc.) until
the Adjacent Properties are developed and the garage is shared with the other
lot owners. The fixed costs associated with the garage (e.g. taxes and
insurance) shall be prorated pursuant to section 1.9 of the Tenancy in Common
Agreement at all times during the Lease Term.

         Landlord reserves the right to make changes to the Common Area and
construct additional buildings on the Adjacent Properties provided such changes
to do materially affect Tenant's access to the Premises or reduce the parking
available to Tenant.

     4.  USE: Tenant shall use the Premises only for the following purposes and

                                    Page 1
<PAGE>

shall not change the use of the Premises without the prior written consent of
Landlord: Office, research and development, marketing, customer training, data
center, light manufacturing, storage and other lawful office related uses.
Tenant shall have the right to erect satellite/microwave transmission devices on
the roof of the Building provided such devices are installed in compliance with
the provisions of paragraph 10 of the Lease. Landlord makes no representation or
warranty that any specific use of the Premises desired by Tenant is permitted
pursuant to any Laws.

     5.   TERM AND RENTAL: The term ("Lease Term") shall be for one hundred
twenty (120) months, commencing on the 23rd day of January, 1995 ("Commencement
Date"), and ending on the 22nd day of January, 2005, ("Expiration Date"). In
addition to all other sums payable by Tenant under this Lease, Tenant shall pay
as base monthly rent ("Base Monthly Rent") for the Premises, as increased
pursuant to paragraph 4(A) below, the sum of One Hundred Sixty Thousand Two
Hundred and No/100 Dollars ($160,200.00). Base Monthly Rent shall be due on or
before the first day of each calendar month during Lease Term. All sums payable
by Tenant under this Lease shall be paid in lawful money of the United States of
America, without offset or deduction, and shall be paid to Landlord at the
address specified in paragraph 1 of this Lease or at such place or places as may
be designated from time to time by Landlord. Base Monthly Rent for any period
less than a calendar month shall be a pro rata portion of the monthly
installment.

          A.  RENTAL ADJUSTMENT: Beginning thirty (30) months after the
Commencement Date, and every thirty (30) months thereafter, the then payable
Base Monthly Rent shall be subject to adjustment based on the increase, if any,
in the Consumer Price Index ("Adjustment Date"). The basis for computing the
adjustment shall be the U.S. Department of Labor, Bureau of Labor Statistic's
Consumer Price Index for All Urban Consumers, All Items, 1982-84=100, for the
San Francisco-Oakland-San Jose area ("Index"). The Index most recently published
preceding the commencement of the Lease (or previous Adjustment Date, as
applicable), shall be considered the "Base Index". If the Index most recently
published preceding the Adjustment Date ("Comparison Index") is greater than the
Base Index, the then payable Base Monthly Rent shall be increased by multiplying
the then payable Base Monthly Rent by a fraction, the numerator of which is the
Comparison Index and the denominator of which is the Base Index. Notwithstanding
any subsequent decrease in the Index, the increase in the CPI for any calendar
year shall never be less than three percent (3%) per year nor more than six
percent (6%) per year. On adjustment of the Base Monthly Rent Landlord shall
notify Tenant by letter stating the new Base Monthly Rent. Landlord's
calculation of the Base Monthly Rent escalation shall be conclusive and binding
unless Tenant objects to said calculation within a thirty (30) day period
following receipt of such determination from Landlord. If the Index base year is
changed so that it differs from 1982-84=100, the Index shall be converted in
accordance with the conversion factor published by the United States Department
of Labor, Bureau of Labor Statistics. If the Index is discontinued or revised
during the Lease Term, such other government index or computation with which it
is replaced shall be used in order to obtain substantially the same result as
would be obtained if the index had not been discontinued or revised.

          B.  EARLY OCCUPANCY: Tenant shall be allowed to occupy the Premises
prior to Commencement Date from and after November 15, 1994, but not earlier
that November 15, 1994. In the event Tenant elects to occupy the Premises prior
to the Commencement Date ("Early Occupancy Period"), such occupancy shall be
subject to all the terms and conditions of the Lease, except that no monthly
rent, property taxes, property insurance or exterior maintenance shall be due or
payable by Tenant during the Early Occupancy Period. Tenant shall, however, be
responsible for the payment of any utilities, janitorial or security services
during the Early Occupancy Period unless Tenant is occupying the building solely
for the purposes of completing Alterations to the Building in which event no
utility payments shall be due during this period.

     6.   LATE CHARGES: Tenant hereby acknowledges that late payment by Tenant
to Landlord of Base Monthly Rent and other sums due hereunder will cause
Landlord to incur costs not contemplated by this Lease, the exact amount of
which would

                                    Page 2
<PAGE>

be extremely difficult to ascertain. Such costs include, but are not limited to,
administrative, processing, accounting charges, and late charges, which may be
imposed on Landlord by the terms of any contract, revolving credit, mortgage or
trust deed covering the Premises. Accordingly, if any installment of Base
Monthly Rent or any other sum due from Tenant shall not be received by Landlord
or Landlord's designee when due, Tenant shall pay to Landlord a late charge
equal to five (5%) percent of such overdue amount which late charge shall be due
and payable on the same date that the overdue amount in question was due.
Landlord agrees to waive said late charge in the event all amounts set forth in
any notice served upon Tenant by Landlord to pay rent or quit in connection with
the overdue amount are paid in full by cashier's check within five (5) days
after Landlord's service upon Tenant of such notice to quit or pay rent. The
parties hereby agree that such late charge represents a fair and reasonable
estimate of the costs Landlord will incur by reason of late payment by Tenant.
Acceptance of such late charge by Landlord shall in no event constitute a waiver
of Tenant's default with respect to such overdue amount, nor prevent Landlord
from exercising any of the other rights and remedies granted hereunder.

IT IS FURTHER MUTUALLY AGREED BETWEEN THE PARTIES AS FOLLOWS:

     7.   POSSESSION: If Landlord, for any reason whatsoever, cannot deliver
possession of the said Premises to Tenant by the Commencement Date, this Lease
shall not be void or voidable, and, except as provided in this paragraph 7,
Landlord shall not be liable to Tenant for any loss or damage resulting
therefrom. In such event the Commencement Date and Expiration Date of the Lease
and all other dates affected thereby shall be revised to conform to the date of
Landlord's delivery of possession. Notwithstanding the foregoing, (i) if
Landlord has not delivered possession of the Premises to Tenant within thirty
(30) days of the date Tenant requests possession, Tenant shall be entitled to
rental abatement hereunder of one (1) day's rent for each day for which
possession is not delivered; and (ii) if Landlord has not delivered possession
of the Premises to Tenant within ninety (90) days of the date Tenant requests
possession, Tenant, upon written notice to Landlord, shall be entitled to
terminate this Lease without further liability to Landlord. Pursuant to the
provisions of paragraph 5(B), in no event shall Tenant be entitled to request
possession earlier that November 15, 1994.

     8.   ACCEPTANCE OF POSSESSION AND COVENANTS TO SURRENDER: Prior to
September 1, 1994, Tenant shall complete an inspection of the building
mechanical and operating systems by contractors selected by Landlord and Tenant.
Landlord shall, at Landlord's sole cost and expense, perform any repair work
identified in such inspection reports to ensure that the Premises are in good
operating condition and repair prior to the Commencement Date. At the conclusion
of such work, Tenant shall accept the Premises as being in good and sanitory
order, condition and repair and accepts the Premises and the other improvements
in their present condition. Tenant further agrees on Expiration Date, or on the
sooner termination of this Lease, to surrender the Premises to Landlord in good
condition and repair, reasonable wear and tear excepted. "Good condition" shall
mean that the interior walls, floors, suspended ceilings, and carpeting within
the Premises will be cleaned to the same condition as existed at the
commencement of the Lease, reasonable wear and tear excepted. "Reasonable wear
and tear" shall mean normal wear of the Premises expected over the duration of
the Lease Term on, including but not limited to, the carpeting, walls, ceiling
tiles, fixtures and operating systems and equipment. Tenant shall ascertain from
Landlord within thirty (30) days before the Expiration Date whether Landlord
desires to have the Premises or any part or parts thereof restored to their
condition as of the Commencement Date or to cause Tenant to surrender all
Alterations in place to Landlord. If Landlord shall so desire, then Tenant shall
remove such Alterations as Landlord may require and shall repair and restore
said Premises or such part or parts thereof before the Expiration Date at
Tenant's sole cost and expense. Tenant on or before the Expiration Date or
sooner termination of this Lease, shall remove all its personal property and
trade fixtures from the Premises, and all property and fixtures not so removed
shall be deemed to be abandoned by Tenant. If the Premises are not surrendered
at the Expiration Date or sooner termination of this Lease in the condition

                                     Page 3
<PAGE>

required by this paragraph, Tenant shall indemnify, defend, and hold harmless
Landlord against loss or liability resulting from delay by Tenant in so
surrendering the Premises including, without limitation, any claims made by any
succeeding tenant founded on such delay.

     9.   USES PROHIBITED: Tenant shall not commit, or suffer to be committed,
any waste upon the said Premises, or any nuisance, or other act or thing which
may disturb the quiet enjoyment of any other tenant in or around the Premises or
allow any sale by auction upon the Premises, or allow the Premises to be used
for any unlawful or objectionable purpose, or place any loads upon the floor,
walls, or ceiling which endanger the structure, or use any machinery or
apparatus which will in any manner vibrate or shake the Premises, or place any
harmful liquids, waste materials, or hazardous materials in the drainage system
of, or upon or in the soils surrounding the Building. No materials, supplies,
equipment, finished products or semi-finished products, raw materials or
articles of any nature or any waste materials, refuse, scrap or debris shall be
stored upon or permitted to remain on any portion of the Premises outside of the
Building proper without Landlord's prior approval, which approval may be
withheld in its sole discretion.

     10.  ALTERATIONS AND ADDITIONS: Tenant intends to make certain alterations
and additions to the existing interior improvements prior to the Commencement
Date. Landlord agrees to pay Tenant on the Commencement Date the sum of Thirty
Thousand and No/100 Dollars ($30,000.00) towards Tenant's planning and design
fees related to this work.

          Tenant shall be entitled without obtaining Landlord's consent, after
initial occupancy to make any alteration or addition to the Premises
("Alterations") which (i) does not affect the structure of the Building, (ii)
cost does not exceed $50,000 per alteration nor an aggregate of $100,000 in any
twelve (12) month period. All other Alterations shall require Landlord's
consent. Tenant shall, at its sole cost and expense, prepare and deliver to
Landlord the proposed architectural and structural plans for all such
Alterations. In the event the Alterations require Landlord's approval as
provided above, Landlord agrees to either (i) approve such Alterations or (ii)
or provide the basis for disapproval within fifteen (15) days of receipt of the
plans. Landlord agrees not to unreasonably withhold approval of any Alterations.
Landlord's failure to respond within such fifteen (15) day period shall be
deemed approval of the Alterations. At the time of consent, Landlord agrees to
advise Tenant whether Landlord will require remove of such Alterations at the
expiration of the Lease Term. In the event Landlord requires removal, any
salvage value of such Alterations shall belong to Tenant.

          After having obtained Landlord's consent, Tenant agrees that it shall
not proceed to make such Alterations until (i) Tenant has obtained all required
governmental approvals and permits, and (ii) Tenant has provided Landlord
reasonable security, in form reasonably approved by Landlord, to protect
Landlord against mechanics' lien claims. Tenant further agrees to provide
Landlord (i) written notice of the anticipated start date and actual start date
of the work, and (ii) a complete set of asbuilt drawings. All Alterations shall
be constructed in compliance with applicable buildings codes and laws. Any
Alterations, except movable furniture and trade fixtures, shall become at once a
part of the realty and belong to Landlord. Alterations which are not to be
deemed as trade fixtures shall include heating, lighting, electrical systems,
air conditioning, partitioning, carpeting, or any other installation which has
become an integral part of the Premises. All Alterations shall be maintained,
replaced or repaired by Tenant at Tenant's sole cost and expense.

     11.  MAINTENANCE OF PREMISES:

          A.  TENANT'S OBLIGATIONS: Tenant shall, at its sole cost, keep and
maintain, repair and replace, said Premises and appurtenances and every part
hereof, including but not limited to, exterior walls, roof, glazing, sidewalks,
parking areas, elevator, plumbing, electrical and HVAC systems, and all the
Tenant Improvements in good and sanitary order, condition, and repair. Tenant
shall provide Landlord with a copy of a

                                     Page 4
<PAGE>

service contract between Tenant and (i) a licensed air-conditioning and heating
contractor which contract shall provide for bi-monthly maintenance of all air
conditioning and heating equipment at the Premises; and (ii) a licensed elevator
maintenance contractor which contract shall provide for monthly maintenance of
all elevator related systems. Tenant shall pay the cost of all air-conditioning
heating, and elevator equipment repairs or replacements which are either
excluded from such service contract or any existing equipment warranties. All
wall surfaces and floor tile are to be maintained in an as good a condition as
when Tenant took possession free of holes, gouges, or defacements.

Tenant shall also be responsible, at its sole cost and expense for the
preventive maintenance of the membrane of the roof, which responsibility shall
be deemed properly discharged if (i) Tenant contracts with a licensed roof
contractor who is reasonably satisfactory to both Tenant and Landlord, at
Tenant's sole cost, to inspect the roof membrane at least every six (6) months,
with the first inspection due the sixth (6th) month after the Commencement Date,
and (ii) Tenant performs, at Tenant's sole cost, all preventive maintenance
recommendations made by such contractor within a reasonable time after such
recommendations are made. Such preventive maintenance might include acts such as
clearing storm gutters and drains, removing debris from the roof membrane,
trimming trees overhanging the roof membrane, applying coating materials to seal
roof penetrations, repairing blisters, and other routine measures. Tenant shall
provide to Landlord a copy of such preventive maintenance contract and paid
invoices for the recommended work. Tenant agrees, at its expense, to water,
maintain and replace, when necessary, any shrubbery and landscaping.

          B.  LANDLORD'S OBLIGATIONS: Landlord shall, at its sole cost and
expense, maintain in good condition, order, and repair, and replace as and when
necessary, the foundation, floor slabs, columns, exterior load bearing walls and
roof structure of the Building. Landlord shall also keep the Common Area and any
part thereof, in good and sanitary order, condition and repair. Tenant shall
reimburse Landlord for the amount payable by the owner of Lot 1 (as set forth in
the Tenancy-In-Common Agreement) for maintenance and repair of the Common Area
under the terms of the Tenancy-In-Common Agreement; provided, however, that if
Tenant is required to reimburse to Landlord in excess of Fifty Thousand Dollars
($50,000) for any particular capital improvement or replacement in the Common
Area, then Tenant may pay its share of such costs pursuant to the provisions of
paragraph 11(C) below.

          C.  AMORTIZATION OF CERTAIN CAPITAL REPLACEMENTS: Notwithstanding the
foregoing, in the event a capital replacement is required during the Lease Term
of the equipment related to building systems or to the roof membrane and such
replacement costs in excess of (i) Fifty Thousand and No/100 Dollars
($50,000.00) per occurrence, or (ii) One Hundred Thousand and No/100 Dollars
($100,000.00) in the aggregate over any twelve (12) calendar month period,
Tenant shall be required to pay (x) the first Fifty Thousand and No/100 Dollars
($50,000.00) of the cost, and (y) that portion of the cost equal to the product
of such remaining cost multiplied by a fraction, the numerator of which is the
number of years remaining in the Lease Term, the denominator of which is the
useful life (in years) of the replacement, which cost shall be amortized over
the remaining Lease Term with interest at eight percent (8%). Landlord shall pay
the balance of such cost.

     12.  HAZARD INSURANCE:

          A.  TENANT'S USE: Tenant shall not use, or permit said Premises, or
any part thereof, to be used, for any purpose other than that for which the said
Premises are hereby leased; and no use shall be made or permitted to be made of
the said Premises, nor acts done, which will cause an increase in premiums or a
cancellation of any insurance policy covering said Premises, or any part
thereof, nor shall Tenant sell or permit to be kept, used or sold, in or about
said Premises, any article which may be prohibited by the standard form of fire
insurance policies. Subject to the provisions of paragraph 17, Tenant shall, at
its sole cost and expense, comply with any and all requirements, pertaining to
said Premises, of any insurance organization or company,

                                     Page 5
<PAGE>

necessary for the maintenance of reasonable fire and public liability insurance,
covering said Premises and appurtenances.

          B.  LANDLORD'S INSURANCE: Landlord agrees to purchase and keep in
force fire, extended coverage, owner's liability, and 12 month rental loss
insurance. The amount of the said insurance shall not exceed the replacement
cost of the Building (not including any Tenant Improvements or Alterations paid
for by Tenant) as determined by Landlord's insurance company's appraisers. The
Tenant agrees to pay to the Landlord as additional rent, on demand, the full
cost of said insurance as evidenced by insurance billings to the Landlord, and
in the event of damage covered by said insurance, the amount of any deductible
under such policy. Payment shall be due to Landlord within ten (10) days after
written invoice to Tenant. Landlord agrees to competitively bid such insurance
not less than once every two (2) years. It is understood and agreed that
Tenant's obligation under this paragraph will be prorated to reflect the
commencement and termination dates of this Lease. The parties reserve the right
to carry earthquake insurance in the future if such cost becomes reasonable as
determined by mutual agreement of Landlord and Tenant.

          C.  TENANT'S INSURANCE: Tenant, at its sole cost, agrees to insure its
personal property, Tenant Improvements paid for by Tenant, and Alterations for
their full replacement value (without depreciation) and to obtain worker's
compensation and public liability and property damage insurance for occurrences
within the Premises with combined limits for bodily injury and property damage
of not less than $1,000,000.00 per occurrence and a general aggregate limit of
not less than $5,000,000.00. Tenant shall name Landlord and Landlord's lender as
an additional insured, shall deliver a copy of the policies and renewal
certificates to Landlord. All such policies shall provide for thirty (30) days'
prior written notice to Landlord of any cancellation, termination, or reduction
in coverage. Notwithstanding the above, Landlord retains the right to have
Tenant provide other forms of insurance which may be reasonably required to
cover future risks.

          D.  WAIVER: Landlord and Tenant hereby waive any and all rights each
may have against the other on account of any loss or damage occasioned to the
Landlord or the Tenant as the case may be, or to the Premises or its contents,
and which may arise from any risk covered by their respective insurance policies
(or which would have been covered had such insurance policies been maintained in
accordance with this Lease), as set forth above. The parties shall use their
reasonable efforts to obtain from their respective insurance companies a waiver
of any right of subrogation which said insurance company may have against the
Landlord or the Tenant, as the case may be.

     13.  TAXES: Tenant shall be liable for, and shall pay prior to delinquency,
all taxes and assessments levied against personal property and trade or business
fixtures, and agrees to pay, as additional rental, all real estate taxes and
assessment installments (special or general) or other impositions or charges
which may be levied on the Premises, upon the occupancy of the Premises and
including any substitute or additional charges which may be imposed during, or
applicable to the Lease Term including real estate tax increases due to a sale
or other transfer of the Premises, as they appear on the City and County tax
bills during the Lease Term, and as they become due. It is understood and agreed
that Tenant's obligation under this paragraph will be prorated to reflect the
Commencement and Expiration Dates. If, at any time during the Lease Term a tax,
excise on rents, business license tax, or any other tax, however described, is
levied or assessed against Landlord, as a substitute or addition in whole or in
part for taxes assessed or imposed on land or Buildings, Tenant shall pay and
discharge his pro rata share of such tax or excise on rents or other tax before
it becomes delinquent, except that this provision is not intended to cover net
income taxes, inheritance, gift or estate tax imposed upon the Landlord. In the
event that a tax is placed, levied, or assessed against Landlord and the taxing
authority takes the position that the Tenant cannot pay and discharge his pro
rata share of such tax on behalf of the Landlord, then at the sole election of
the Landlord, the Landlord may increase the rental charged hereunder by the
exact amount of such tax and Tenant shall pay such increase as additional rent
hereunder. If by virtue of any application or proceeding brought by

                                    Page 6
<PAGE>

or on behalf of Landlord, there results a reduction in the assessed value of the
Building during the Lease Term, Tenant agrees to reimburse Landlord its out of
pocket costs incurred by Landlord in connection with such application or
proceeding.

          Notwithstanding the foregoing, if property taxes increase during the
Lease Term as a result of a reassessment due to a voluntary change of ownership,
Tenant's shall be responsible for payment of the resulting property tax increase
as follows: during the first twelve month period following the transfer, Tenant
shall be responsible for payment of twenty five percent (25%) of the tax
increase; during the second twelve month period following the transfer, Tenant
shall be responsible for payment of fifty percent (50%) of the tax increase,
during third twelve month period following the transfer, Tenant shall be
responsible for payment of seventy five percent (75%) of the tax increase,
thereafter Tenant shall be responsible for payment of the entire tax increase.

     14.  UTILITIES: Tenant shall pay directly to the providing utility all
water, gas, heat, light, power, telephone and other utilities supplied to the
Premises. Landlord shall not be liable for a loss of or injury to property,
however occurring, through or in connection with or incidental to furnishing or
failure to furnish any utilities to the Premises and Tenant shall not be
entitled to abatement or reduction of any portion of the Base Monthly Rent so
long as any failure to provide and furnish the utilities to the Premises is due
to a cause beyond the Landlord's reasonable control.

     15.  ABANDONMENT: Tenant shall not abandon the Premises at any time during
the Lease Term; and if Tenant shall abandon, surrender said Premises, or be
dispossessed by process of law, or otherwise, any personal property belonging to
Tenant and left on the Premises shall be deemed to be abandoned, at the option
of Landlord, except such property as may be mortgaged to Landlord. Tenant shall
have the right to vacate all of the Premises for up to thirty (30) days in any
given year without being in default under the Lease. Further Tenant shall have
the right to vacate any portion of the Building during the Lease Term,
regardless of duration, without being in default under the Lease, so long as
Tenant continues to occupy a portion of the Building and pays the rent and
fulfills its other obligations under the Lease.

     16.  FREE FROM LIENS: Tenant shall keep the Premises free from any liens
arising out of any work performed, materials furnished, or obligations incurred
by Tenant or claimed to have been performed for Tenant. In the event Tenant
fails to discharge any such lien within ten (10) days after receiving notice of
the filing, Landlord shall be entitled to discharge such lien at Tenant's
expense and all resulting costs incurred by Landlord, including attorney's fees
shall be due from Tenant as additional rent.

     17.  COMPLIANCE WITH GOVERNMENTAL REGULATIONS: Tenant shall, at its sole
cost and expense, comply with all of the requirements of all Municipal, State
and Federal authorities now in force, or which may hereafter be in force,
pertaining to the said Premises, and shall faithfully observe in the use of the
Premises all Municipal ordinances and State and Federal statutes now in force or
which may hereafter be in force. The judgment of any court of competent
jurisdiction, or the admission of Tenant in any action or proceeding against
Tenant, whether Landlord be a party thereto or not, that Tenant has violated any
such ordinance or statute in the use of the Premises, shall be conclusive of
that fact as between Landlord and Tenant. Notwithstanding the foregoing, if any
improvement to the Premises is required as a result of any future laws or
regulations affecting the Premises not related to Tenant's specific use of the
Premises, and provided further said improvement is not required because of
Alterations made by Tenant, the cost of such improvements shall be allocated
between Landlord and Tenant such that Tenant shall pay to Landlord upon
completion of such improvement, the portion of the cost thereof equal to the
remaining number of years in the lease term divided by the anticipated useful
life of such improvement.

     18.  TOXIC WASTE AND ENVIRONMENTAL DAMAGE:

          A.  TENANT'S RESPONSIBILITY: Without the prior written consent of

                                    Page 7
<PAGE>

Landlord, Tenant shall not bring, use, or permit upon the Premises, or generate,
create, release, emit, or dispose (nor permit any of the same) from the Premises
any chemicals, toxic or hazardous gaseous, liquid or solid materials or waste,
including without limitation, material or substance having characteristics of
ignitability, corrosivity, reactivity, or toxicity (other than small quantities
of toxic substances such as photocopy toner, photography chemicals and the like
typically used by office users) or substances or materials which are listed on
any of the Environmental Protection Agency's lists of hazardous wastes or which
are identified in Sections 66680 through 66685 of Title 22 of the California
Administrative Code as the same may be amended from time to time ("Hazardous
Materials"). In order to obtain consent, Tenant shall deliver to Landlord its
written proposal describing the toxic material to be brought onto the Premises,
measures to be taken for storage and disposal thereof, safety measures to be
employed to prevent pollution of the air, ground, surface and ground water.
Landlord's approval may be withheld in its reasonable judgment. In the event
Landlord consents to Tenant's use of Hazardous Materials on the Premises, Tenant
represents and warrants that Tenant will (i) adhere to all reporting and
inspection requirements imposed by Federal, State, County or Municipal laws,
ordinances or regulations and will provide Landlord a copy of any such reports
or agency inspections, (ii) obtain and provide Landlord copies of all necessary
permits required for the use and handling Hazardous Materials on the Premises,
(iii) enforce Hazardous Materials handling and disposal practices consistent
with industry standards, (iv) surrender the Premises free from any Hazardous
Materials arising from Tenant's bringing, using, permitting, generating,
emitting or disposing of Hazardous Materials, and (v) properly close the
facility with regard to Hazardous Materials including the removal or
decontamination of any process piping, mechanical ducting, storage tanks,
containers, or trenches which have come into contact with Hazardous Materials
and obtain a closure certificate from the local administering agency prior to
the Expiration Date.

          B.  TENANT'S INDEMNITY REGARDING HAZARDOUS MATERIALS: Tenant shall
comply, at its sole cost, with all laws pertaining to, and shall indemnify and
hold Landlord harmless from any claims, liabilities, costs or expenses incurred
or suffered by Landlord arising from such bringing, using, permitting,
generating, emitting or disposing of Hazardous Materials by Tenant. Tenant's
indemnification and hold harmless obligations include, without limitation, (i)
claims, liability, costs or expenses resulting from or based upon
administrative, judicial (civil or criminal) or other action, legal or
equitable, brought by any private or public person under common law or under the
Comprehensive Environmental Response, Compensation and Liability Act of 1980
("CERCLA"), the Resource Conservation and Recovery Act of 1980 ("RCRA") or any
other Federal, State, County or Municipal law, ordinance or regulation, (ii)
claims, liabilities, costs or expenses pertaining to the identification,
monitoring, cleanup, containment, or removal of Hazardous Materials from soils,
riverbeds or aquifers including the provision of an alternative public drinking
water source, and (iii) all costs of defending such claims.

          C.  ACTUAL RELEASE BY TENANT: Tenant agrees to notify Landlord of any
lawsuits which relate to, or orders which relate to the remedying of, the actual
release of Hazardous Materials on or into the soils or groundwater at or under
the Premises. Tenant shall also provide to Landlord all notices required by
Section 25359.7(b) of the Health and Safety Code and all other notices required
by law to be given to Landlord in connection with Hazardous Materials. Without
limiting the foregoing, Tenant shall also deliver to Landlord, within twenty
(20) days after receipt thereof, any written notices from any governmental
agency alleging a material violation of, or material failure to comply with, any
federal, state or local laws, regulations, ordinances or orders, the violation
of which of failure to comply with, poses a foreseeable and material risk of
contamination of the groundwater or injury to humans (other than injury solely
to Tenant, its agents and employees within the Improvements on the Property).

          In the event of any release on or into the Premises or into the soil
or groundwater under the Premises of any Hazardous Materials used, treated,
stored or disposed of by Tenant, Tenant agrees to comply, at its sole cost and
expense, with all laws, regulations, ordinances and orders of any federal, state
or local agency relating to

                                    Page 8
<PAGE>

the monitoring or remediation of such Hazardous Materials. In the event of any
such release of Hazardous Materials, Tenant agrees to meet and confer with
Landlord and its Lender to attempt to eliminate and mitigate any financial
exposure to such Lender and resultant exposure to Landlord under California Code
of Civil Procedure section 736(b) as a result of such release and promptly to
take reasonable monitoring, cleanup and remedial steps given, inter alia, the
historical uses to which the Property has and continues to be used, the risks to
public health posed by the release, the then available technology and the costs
of remediation, cleanup and monitoring, consistent with acceptable customary
practices for the type and severity of such contamination and all applicable
laws. Nothing in the preceding sentence shall eliminate, modify or reduce the
obligation of Tenant under paragraph 20(B) of this Lease to indemnify and hold
Landlord harmless from any claims liabilities, costs or expenses incurred or
suffered by Landlord as provided in paragraph 20(B) of this Lease. Tenant shall
provide Landlord prompt written notice of Tenant's monitoring, cleanup and
remedial steps.

          In the absence of an order of any federal, state or local governmental
or quasi-governmental agency relating to the cleanup, remediation or other
response action required by applicable law, any dispute arising between Landlord
and Tenant concerning Tenant's obligation to Landlord under this Paragraph C
concerning the Level, method, and manner of cleanup, remediation or response
action required in connection with such a release of Hazardous Materials shall
be resolved by mediation and/or arbitration pursuant to the provisions of
paragraph 44 of this Lease.

          D.  LANDLORD'S INDEMNITY REGARDING HAZARDOUS MATERIALS: Landlord shall
indemnify and hold Tenant harmless from any claims, liabilities, costs or
expenses incurred or suffered by Tenant related to the removal, investigation,
monitoring or remediation of Hazardous Materials which are present on the
Premises as of the Commencement Date. Landlord's indentification and hold
harmless obligations include, without limitation, (i) claims, liability, costs
or expenses resulting from or based upon administrative, judicial (civil or
criminal) or other action, legal or equitable, brought by any private or public
person under common law or under the Comprehensive Environmental Response,
Compensation and Liability Act of 1980 ("CERCLA"), the Resource Conservation and
Recovery Act of 1980 ("RCRA") or any other Federal, State, County or Municipal
law, ordinance or regulation, (ii) claims, liabilities, costs or expenses
pertaining to the identification, monitoring, cleanup, containment, or removal
of Hazardous Materials from soils, riverbeds or aquifers including the provision
of an alternative public drinking water source, and (iii) all costs of defending
such claims. In no event shall Landlord be liable for any consequential damages
suffered or incurred by Tenant as a result of any such contamination.

          E.  ENVIRONMENTAL MONITORING: Landlord and its agents shall have the
right, at Landlord's sole cost and expense, to inspect, investigate, sample
and/or monitor the Premises, including any air, soil, water, groundwater or
other sampling or any other testing, digging, drilling or analysis to determine
whether Tenant is complying with the terms of this paragraph 18. If Landlord
discovers that Tenant is not in compliance with the terms of this paragraph 18,
any such costs incurred by Landlord, including attorneys' and consultants' fees
shall be due and payable by Tenant to Landlord within five days following
Landlord's written demand therefore.

     19.  INDEMNITY: As a material part of the consideration to be rendered to
Landlord, Tenant hereby waives all claims against Landlord for damages to goods,
wares and merchandise, and all other personal property in, upon or about said
Premises and for injuries to persons in or about said Premises, from any cause
arising at any time to the fullest extent permitted by law, and Tenant shall
indemnify and hold Landlord exempt and harmless from any damage or injury to any
person, or to the goods, wares and merchandise and all other personal property
of any person, arising from the use of the Premises, Building, and/or Project by
Tenant, its employees, contractors, agents and invitees or from the failure of
Tenant to keep the Premises in good condition and repair, as herein provided,
except to the extent due to the active negligence or willful misconduct of
Landlord. Further, in the event Landlord is made party to any litigation due to
the acts or omission of Tenant, its employees, contractors, agents and invitees,

                                    Page 9
<PAGE>

Tenant will indemnify and hold Landlord harmless from any such claim or
liability including Landlord's costs and expenses and reasonable attorney's fees
incurred in defending such claims.

     20.  ADVERTISEMENTS AND SIGNS: Tenant will not place or permit to be
placed, in, upon or about the said Premises any signs not approved by the city
or other governing authority. Any sign so placed on the Premises shall be
removed by Tenant, at its expense, prior to the Expiration Date or promptly
following the earlier termination of the lease and Tenant shall repair, at its
sole cost and expense, any damage or injury to the Premises caused thereby, and
if not so removed by Tenant then Landlord may have same so removed at Tenant's
expense.

     21.  ATTORNEY'S FEES: In case a suit or alternative form of dispute
resolution should be brought for the possession of the Premises, for the
recovery of any sum due hereunder, or because of the breach of any other
covenant herein, the losing party shall pay to the prevailing party a reasonable
attorney's fee as part of its costs which shall be deemed to have accrued on the
commencement of such action. In addition, the prevailing party shall be entitled
to recover all costs and expenses including reasonable attorney's fees incurred
by the prevailing party in enforcing any judgment or award against the other
party. The foregoing provision relating to post-judgment costs is intended to be
severable from all other provisions of this Lease.

     22.  TENANT'S DEFAULT: The occurrence of any of the following shall
constitute a material default and breach of this Lease by Tenant: a) Any failure
by Tenant to pay any rent under this Lease ten (10) days following Tenant's
receipt of written notice from Landlord that such rent is due under this Lease
and has not been received; b) The abandonment of the Premises by Tenant; c) A
failure by Tenant to observe and perform any other provision of this Lease to be
observed or performed by Tenant, where such failure continues for thirty (30)
days after written notice thereof by Landlord to Tenant; provided, however, that
if the nature of such default is such that the same cannot reasonably be cured
within such thirty (30) day period Tenant shall not be deemed to be in default
if Tenant shall within such period commence such cure and thereafter diligently
prosecute the same to completion; d) The making by Tenant of any general
assignment for the benefit of creditors; the filing by or against Tenant of a
petition to have Tenant adjudged a bankrupt or of a petition for reorganization
or arrangement under any law relating to bankruptcy (unless, in the case of a
petition filed against Tenant, the same is dismissed after the filing); the
appointment of a trustee or receiver to take possession of substantially all of
Tenant's assets located at the Premises or of Tenant's interest in this Lease,
where possession is not restored to Tenant within thirty (30) days; or the
attachment, execution or other judicial seizure of substantially all of Tenant's
assets located at the Premises or of Tenant's interest in this Lease, where such
seizure is not discharged within thirty (30) days. The notice requirements set
forth herein are in lieu of and not in addition to the notices required by
California Code of Civil Procedure Section 1161. Any notice given by Landlord to
Tenant pursuant to California Civil Code 1161 with respect to any failure by
Tenant to pay rent under this Lease on or before the date the rent is due shall
provide Tenant with a period of no less than ten (10) days to pay such rent or
quit.

          A.  REMEDIES: In the event of any such default by Tenant, then in
addition to any other remedies available to Landlord at law or in equity,
Landlord shall have the immediate option to terminate this Lease and all rights
of Tenant hereunder by giving written notice of such intention to terminate. In
the event that Landlord shall elect to so terminate this Lease then Landlord may
recover from Tenant: a) the worth at the time of award of any unpaid rent which
had been earned at the time of such termination; plus b) the worth at the time
of award of the amount by which the unpaid rent which would have been earned
after termination until the time of award exceeds the amount of such rental loss
for the same period that Tenant proves could have been reasonably avoided; plus
c) the worth at the time of award of the amount by which the unpaid rent for the
balance of the Lease Term after the time of award exceeds the amount of such
rental loss that Tenant proves could be reasonably avoided; plus d) any other
amount necessary to compensate Landlord for all the detriment proximately caused
by Tenant's

                                    Page 10
<PAGE>

failure to perform its obligations under this Lease or which in the ordinary
course of things would be likely to result therefrom, and e) at Landlord's
election, such other amounts in addition to or in lieu of the foregoing as may
be permitted from time to time by applicable California law. The term "rent", as
used herein, shall be deemed to be and to mean the minimum monthly installments
of Base Monthly Rent and all other sums required to be paid by Tenant pursuant
to the terms of this Lease, all other such sums being deemed to be additional
rent due hereunder. As used in (a) and (b) above, the "worth at the time of
award" is to be computed by allowing interest at the rate of the discount rate
of the Federal Reserve Bank of San Francisco plus five (5%) percent per annum.
As used in (c) above, the "worth at the time of award" is to 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 (1%) percent.

           B.  RIGHT TO RE-ENTER: In the event of any such default by Tenant,
Landlord shall also have the right, with or without terminating this Lease, to
re-enter the Premises and remove all persons and property from the Premises;
such property may be removed and stored in a public warehouse or elsewhere at
the cost of and for the account of Tenant and disposed of by Landlord in any
manner permitted by law.

           C.  ABANDONMENT:  In the event of the abandonment of the Premises by
Tenant or in the event that Landlord shall elect to re-enter as provided in
paragraph 22(B) above or shall take possession of the Premises pursuant to legal
proceeding or pursuant to any notice provided by law, then if Landlord does not
elect to terminate this Lease as provided in paragraph 22(A) above, then the
provisions of California Civil Code Section 1951.4, (Landlord may continue the
lease in effect after Tenant's breach and abandonment and recover rent as it
becomes due, if Tenant has a right to sublet and assign, subject only to
reasonable limitations) as amended from time to time, shall apply and Landlord
may from time to time, without terminating this Lease, either recover all rental
as it becomes due or relet the Premises or any part thereof for such term or
terms and at such rental or rentals and upon such other terms and conditions as
Landlord in its sole discretion may deem advisable with the right to make
alterations and repairs to the Premises. In the event that Landlord shall elect
to so relet, then rentals received by Landlord from such reletting shall be
applied: first, to the payment of any indebtedness other than Base Monthly Rent
due hereunder from Tenant to Landlord; second, to the payment of any cost of
such reletting; third, to the payment of the cost of any alterations and repairs
to the Premises; fourth, to the payment of Base Monthly Rent due and unpaid
hereunder; and the residue, if any, shall be held by Landlord and applied in
payment of future Base Monthly Rent as the same may become due and payable
hereunder. Landlord shall have no obligation to relet the Premises following a
default if Landlord has other available space within the Building or Project.
Should that portion of such rentals received from such reletting during any
month, which is applied by the payment of rent hereunder, be less than the rent
payable during that month by Tenant hereunder, then Tenant shall pay such
deficiency to Landlord immediately upon demand therefor by Landlord. Such
deficiency shall be calculated and paid monthly. Tenant shall also pay to
Landlord, as soon as ascertained, any costs and expenses incurred by Landlord in
such reletting or in making such alterations and repairs not covered by the
rentals received from such reletting.

           D.  NO TERMINATION:  No re-entry or taking possession of the Premises
by Landlord pursuant to 22(B) or 22(C) of this Article 22 shall be construed as
an election to terminate this Lease unless a written notice of such intention be
given to Tenant or unless the termination thereof be decreed by a court of
competent jurisdiction. Notwithstanding any reletting without termination by
Landlord because of any default by Tenant, Landlord may at any time after such
reletting elect to terminate this Lease for any such default.

     23.   SURRENDER OF LEASE:  The voluntary or other surrender of this Lease
by Tenant, or a mutual cancellation thereof, shall not automatically effect a
merger of the Lease with Landlord's ownership of the Premises. Instead, at the
option of Landlord, Tenant's surrender may terminate all or any existing
sublease or subtenancies, or may operate as an assignment to Landlord of any or
all such subleases

                                    Page 11
<PAGE>

or subtenancies, thereby creating a direct Landlord-Tenant relationship between
Landlord and any subtenants.

     24.   THIS PARAGRAPH INTENTIONALLY LEFT BLANK:

     25.   LANDLORD'S DEFAULT:  In the event of Landlord's failure to perform
any of its covenants or agreements under this Lease, Tenant shall give Landlord
written notice of such failure and shall give Landlord thirty (30) days or such
other reasonable opportunity to cure or to commence to cure such failure prior
to any claim for breach or for damages resulting from such failure. In addition,
upon any such failure by Landlord, Tenant shall give notice by registered or
certified mail to any person or entity with a security interest in the Premises
("Mortgagee") that has provided Tenant with notice of its interest in the
Premises, and shall provide such Mortgagee a reasonable opportunity to cure such
failure, including such time to obtain possession of the Premises by power of
sale or judicial foreclosure, if such should prove necessary to effectuate a
cure. In no event, however, shall the period of time for Mortgagee to obtain
possession exceed one hundred twenty (120) days. Tenant agrees that each of the
Mortgagees to whom this Lease has been assigned is an expressed third party
beneficiary hereof. Tenant shall not make any prepayment of rent more than one
(1). month in advance without the prior written consent of such Mortgagee.
Tenant waives any right under California Civil Code Section 1950.7 or any other
present or future law to the collection of any payment or deposit from such
Mortgagee or any purchaser at a foreclosure sale of such Mortgagee's interest
unless such Mortgagee or such purchaser shall have actually received and not
refunded the applicable payment or deposit.

     26.   NOTICES:  All notices, demands, requests, or consents required to be
given under this Lease shall be sent in writing by U.S. certified mail, return
receipt requested, or by personal delivery addressed to the party to be notified
at the address for such party specified in paragraph 1 of this Lease, or to such
other place as the party to be notified may from time to time designate by at
least fifteen (15) days prior notice to the notifying party.

     27.   ENTRY BY LANDLORD:  Tenant shall permit Landlord and his agents, upon
prior notice except in the case of emergency, to enter into and upon said
Premises at all reasonable times subject to any security regulations of Tenant
for the purpose of inspecting the same or for the purpose of maintaining the
Premises or for the purpose of making repairs, alterations or additions to any
other portion of said Premises or for the purpose of erecting additional
building(s) and improvements on the land where the Premises are situated, or on
adjacent land owned by Landlord, including the erection and maintenance of such
scaffolding, canopies, fences and props as may be required without any abatement
or reduction of rent or without any liability to Tenant for any loss of
occupation or quiet enjoyment of the Premises thereby occasioned. Tenant shall
permit Landlord and his agents, at any time within one hundred eighty (180) days
prior to the Expiration Date (or at any time during the Lease if Tenant is in
default hereunder), to place upon the Premises "For Lease" signs and exhibit the
Premises to real estate brokers and prospective tenants at reasonable hours.

     28.   DESTRUCTION OF PREMISES:

           A.  DESTRUCTION BY AN INSURED CASUALTY:  In the event of a partial
destruction of the Premises by a casualty for which Landlord has received
insurance proceeds sufficient to repair the damage or destruction during the
Lease Term from any cause, Landlord shall forthwith repair the same to the
extent of such proceeds, provided such repairs can be made within one hundred
twenty (120) days from the date of receipt of all governmental approvals
necessary under the laws and regulations of State, Federal, County or Municipal
authorities (as reasonably determined by Landlord), and such partial destruction
shall in no way annual or void this Lease, except that Tenant shall be entitled
to a proportionate reduction of Base Monthly Rent and additional rent from the
date of destruction until completion of the repairs, such proportionate
reduction to be based upon the extent to which the making of such repairs shall
interfere with the business carried on by Tenant in the Premises, in the
reasonable

                                    Page 12
<PAGE>

judgment of Landlord. For purposes of this paragraph "partial destruction" shall
mean destruction of no greater than one-third (1/3) of the replacement cost of
the Premises, including the replacement cost of the Tenant Improvements paid for
by Landlord. In the event the Premises are more than partially destroyed, or in
the event the repairs cannot be made in one hundred twenty (120) days or the
Premises are only partially destroyed but Landlord does not actually receive
insurance proceeds sufficient to repair the damage, Landlord or Tenant may elect
to terminate this Lease within fifteen (15) days of determination by Landlord of
the foregoing. Landlord shall not be required to restore Alterations or replace
Tenant's fixtures or personal property. In respect to any partial destruction
which Landlord is obligated to repair or may elect to repair under the terms of
this paragraph, the provision of Section 1932, Subdivision 2, and of Section
1933, Subdivision 4, of the Civil Code of the State of California and any other
similarly enacted statute are waived by Tenant and the provisions of this
paragraph 28 shall govern in the case of such destruction.

           B.  DESTRUCTION BY AN UNINSURED CASUALTY:  In the event of a total or
partial destruction of the Premises by an uninsured casualty, the Lease shall
automatically terminate, unless (i) Landlord elects to rebuild, and (ii) the
damage can be repaired within one hundred twenty (120) days.

           C.  DESTRUCTION DURING THE LAST YEAR OF THE LEASE TERM:  In the event
of an insured or uninsured casualty during the last year of the Lease Term which
would take more than sixty (60) days to repair, either Landlord or Tenant shall
have the right to terminate the Lease.

     29.   ASSIGNMENT OR SUBLEASE:

           A.  CONSENT BY LANDLORD: In the event Tenant desires to assign this
Lease or any interest therein including, without limitation, a pledge, mortgage
or other hypothecation, or sublet the Premises or any part thereof, Tenant shall
deliver to Landlord executed counterparts of any such agreement and of all
ancillary agreements with the proposed assignee or subtenant, financial
statements, and any additional information as reasonably required by Landlord to
determine whether it will consent to the proposed assignment or sublease. The
notice shall give the name and current address of the proposed
assignee/subtenant, proposed use of the Premises, rental rate and current
financial statement; and upon request to Tenant, Landlord shall be given
additional information as reasonably required by Landlord to determine whether
it will consent to the proposed assignment or sublease. Landlord shall then have
a period of fifteen (15) days following receipt of the foregoing agreement,
statements and additional information within which to notify Tenant in writing
that Landlord elects (i) to permit Tenant to assign or sublet such space to the
named assignee/subtenant on the terms and conditions set forth in the notice, or
(ii) to refuse consent. If Landlord should fail to notify Tenant in writing of
such election within said fifteen (15) day period, Landlord shall be deemed to
have elected option (i) above. Landlord's consent (which must be in writing and
in a form reasonably satisfactory to Landlord) to the proposed assignment or
sublease shall not be unreasonably withheld, provided and upon condition that:
(i) The proposed assignee or subtenant is engaged in a business that is limited
to the use expressly permitted under this Lease; (ii) The proposed assignee or
subtenant is a company with sufficient financial worth and management ability to
undertake the financial obligation of this Lease, and Landlord has been
furnished with reasonable proof thereof; (iii) The proposed assignment or
sublease shall be in form reasonably satisfactory to Landlord; (iv) Tenant shall
reimburse Landlord on demand for any costs that may be incurred by Landlord in
connection with said assignment or sublease, including the costs of making
investigations as to the acceptability of the proposed assignee or subtenant and
legal costs incurred in connection with the granting of any requested consent up
to a maximum amount of $5,000; and (v) Tenant shall not have advertised or
publicized in any way the availability of the Premises without prior notice to
Landlord. In the event all or any one of the foregoing conditions are not
satisfied, Landlord may, in its sole discretion, withhold its consent to the
proposed assignment or sublease.

                                    Page 13
<PAGE>

           B.  ASSIGNMENT OR SUBLETTING CONSIDERATION:  Any rent or other
economic consideration received by Tenant under any such sublease and assignment
in excess of the rent payable hereunder, after the net unamortized cost of the
Tenant Improvements for which Tenant has itself paid, and reasonable subletting
and assignment costs including lease commissions, shall be divided and paid
fifty percent (50%) to Landlord and fifty percent (50%) to Tenant. Tenant's
obligation to pay over Landlord's portion of the consideration shall constitute
an obligation for additional rent hereunder. The above provisions relating to
Landlord's right to terminate the Lease and relating to the allocation of bonus
rent are independently negotiated terms of the Lease, constitute a material
inducement for the Landlord to enter into the Lease, and are agreed as between
the parties to be commercially reasonable. No assignment or subletting by Tenant
shall relieve Tenant of any obligation under this Lease. Any assignment or
subletting which conflicts with the provisions hereof shall be void.

           C.  NO RELEASE:  Any assignment or sublease shall be made only if and
shall not be effective until the assignee or subtenant shall execute,
acknowledge and deliver to Landlord an agreement, in form and substance
satisfactory to Landlord, whereby the assignee or subtenant shall assume all of
the obligations of this Lease on the part of Tenant to be performed or observed
and shall be subject to all of the covenants, agreements, terms, provisions and
conditions contained in this Lease. Notwithstanding any such sublease or
assignment and the acceptance of rent by Landlord from any subtenant or
assignee, Tenant and any guarantor shall and will remain fully liable for the
payment of the rent and additional rent due, and to become due hereunder, for
the performance of all of the covenants, agreements, terms, provisions and
conditions contained in this Lease on the part of Tenant to be performed and for
all acts and omissions of any licensee, subtenant, assignee or any other person
claiming under or through any subtenant or assignee that shall be in violation
of any of the terms and conditions of this Lease, and any such violation shall
be deemed to be a violation by Tenant. Tenant shall further indemnify, defend
and hold Landlord harmless from and against any and all losses, liabilities,
damages, costs and expenses. (including reasonable attorney fees) resulting from
any claims that may be made against Landlord by the proposed assignee or
subtenant or by any real estate brokers or other persons claiming a commission
or similar compensation in connection with the proposed assignment or sublease.

           D.  EFFECT OF DEFAULT:  In the event of Tenant's default, Tenant
hereby assigns all rents due from any assignment or subletting to Landlord as
security for performance of its obligations under this Lease and Landlord may
collect such rents as Tenant's Attorney-in-Fact, except that Tenant may collect
such rents unless a default occurs as described in paragraph 22 and 24 above.
The termination of this Lease due to Tenant's default shall not automatically
terminate any assignment or sublease then in existence; at the election of
Landlord, such assignment or sublease shall survive the termination of this
Lease and, upon such election, the assignee or subtenant shall attorn to
Landlord and Landlord shall undertake the obligations of the Tenant under the
sublease or assignment; provided the Landlord shall not be liable for prepaid
rent, security deposits or other defaults of the Tenant to the subtenant or
assignee, or any acts or omissions of Tenant, its agents, employees, contractors
or invitees.

           E.  PERMITTED TRANSFERS:  Tenant may, without Landlord's prior
written consent, sublet the Premises or assign the Lease to: (i) a subsidiary,
affiliate, division or corporation controlled or under common control with
Tenant; (ii) a successor corporation related to Tenant by merger, consolidation,
non-bankruptcy reorganization, or government action; or (iii) a purchaser of
substantially all of Tenant's assets, provided, however, that the subtenant or
assignee has a net worth not less than the net worth of Tenant as of the date of
such transfer. For the purpose of this Lease, sale of Tenant's capital stock
through any public exchange shall not be deemed an assignment, subletting, or
any other transfer of the Lease or the Premises.

     30.   CONDEMNATION:  If any part of the Premises shall be taken for any
public or quasi-public use, under any statute or by right of eminent domain or
private purchase in lieu thereof, and only a part thereof remains which is
susceptible of

                                    Page 14
<PAGE>

occupation hereunder, this Lease shall as to the part so taken, terminate as of
the day before title shall vest in the condemnor or purchaser ("Vesting Date"),
and the Base Monthly Rent payable hereunder shall be adjusted so that the Tenant
shall be required to pay for the remainder of the Lease Term only such portion
of such Base Monthly Rent as the value of the part remaining after such taking
bears to the value of the entire Premises prior to such taking. If all of the
Premises, or such part thereof be taken so that there does not remain a portion
susceptible for occupation hereunder, this Lease shall thereupon terminate on
the Vesting Date. If a part or all of the Premises be taken, all compensation
awarded upon such taking shall go to the Landlord and the Tenant shall have no
claim thereto but Landlord shall cooperate with Tenant, without cost to
Landlord, to recover compensation for damage to or taking of any Alterations or
for Tenant's moving costs. Tenant hereby waives the provisions of California
Code of Civil Procedures Section 1265.130 and any other similarly enacted statue
are waive by Tenant and the provisions of this paragraph 30 shall govern in the
case of such destruction.

     31.   EFFECTS OF CONVEYANCE:  The term "Landlord" as used in this Lease,
means only the owner for the time being of the Premises so that, in the event of
any sale or other conveyance of the Premises, or in the event of a master lease
of the Premises, the Landlord shall be and hereby is entirely freed and relieved
of all covenants and obligations of the "Landlord" hereunder arising from and
after the conveyance, and it shall be deemed and construed, without further
agreement between the parties and the purchaser at any such sale, or the master
tenant of the Premises, that the purchaser or master tenant of the Premises has
assumed and agreed to carry out any and all covenants and obligations of the
Landlord hereunder. Such transferor shall transfer and deliver Tenant's security
deposit to the purchaser at any such sale or the master tenant of the Premises,
and thereupon the such transferor shall be discharged from any further liability
in reference thereto.

     32.   SUBORDINATION:  In the event Landlord notifies Tenant in writing,
this Lease shall be subordinate to any ground Lease, deed of trust, or other
hypothecation for security now or hereafter placed upon the real property of
which the Premises are a part and to any and all advances made on the security
thereof and to renewals, modifications, replacements and extensions thereof
provided that Tenant receives from the lender or other lien holder requesting
such subordination an agreement in writing providing that if the lien holder
acquires title to the real property on which the Premises are located, such
party shall not terminate this Lease so long as Tenant is not in default
hereunder, and such party shall recognize all of the rights of Tenant under this
Lease. Tenant agrees to promptly execute and deliver any documents which may be
required to effectuate such subordination. At the request of any lender, Tenant
agrees to execute and deliver any reasonable modifications of this Lease which
do not materially adversely affect Tenant's rights hereunder.

           Landlord shall attempt to deliver to Tenant a non-disturbance
agreement from the existing lender on the Building in a form reasonably
acceptable to the parties within sixty (60) days from the date of execution of
this Lease. In the event Landlord is unable to deliver the non-disturbance,
Tenant shall have the right to terminate the Lease by providing Landlord written
notice of such election within five (5) days following the expiration of such
sixty (60) day period.

     33.   WAIVER:  The waiver by Landlord of any breach of any term, covenant
or condition, herein contained shall not be deemed to be a waiver of such term,
covenant or condition or any subsequent breach of the same or any other term,
covenant or condition herein contained. The subsequent acceptance of rent
hereunder by Landlord shall not be deemed to be a waiver of any preceding breach
by Tenant of any term, covenant or condition of this Lease, other than the
failure of Tenant to pay the particular rental so accepted, regardless of
Landlord's knowledge of such preceding breach at the time of acceptance of such
rent. No payment by Tenant or receipt by Landlord of a lesser amount than any
installment of rent due shall be deemed to be other than payment on account of
the amount due. No delay or omission in the exercise of any right or remedy by
Landlord shall impair such right or remedy or be constructed as a

                                    Page 15
<PAGE>

waiver thereof by Landlord. No act or conduct of Landlord, including, without
limitation, the acceptance of keys to the Premises, shall constitute acceptance
of the surrender of the Premises by Tenant before the Expiration Date (only
written notice from Landlord to Tenant of acceptance shall constitute such
acceptance of surrender of the Premises). Landlord's consent to or approval of
any act by Tenant which require Landlord's consent or approvals shall not be
deemed to waive or render unnecessary Landlord's consent to or approval of any
subsequent act by Tenant.

     34.   HOLDING OVER:  Any holding over after the termination or Expiration
Date, shall be construed to be a tenancy from month to month, terminable on
thirty (30) days written notice from either party, and Tenant shall pay Base
Monthly Rent to Landlord at a rate equal to one hundred fifty percent (150%) of
the Base Monthly Rent due in the month preceding the termination or Expiration
Date plus all other amounts payable by Tenant under this Lease. Any holding over
shall otherwise be on the terms and conditions herein specified, except those
provisions relating to the Lease Term and any options to extend or renew, which
provisions shall be of no further force and effect following the expiration of
the applicable exercise period. Tenant shall indemnify, defend, and hold
Landlord harmless from all loss or liability (including, without limitation, any
loss or liability resulted from any claim against Landlord made by any
succeeding tenant) founded on or resulting from Tenant's failure to timely
surrender the Premises to Landlord and losses to Landlord due to lost
opportunities to lease the Premises to succeeding tenants.

     35.   SUCCESSORS AND ASSIGNS:  The covenants and conditions herein
contained shall, subject to the provisions of paragraph 29, apply to and bind
the heirs, successors, executors, administrators and assigns of all the parties
hereto; and all of the parties hereto shall be jointly and severally liable
hereunder.

     36.   ESTOPPEL CERTIFICATES:  Either party shall at any time during the
Lease Term, within ten (10) days following written notice from the other party,
be obligated to execute and deliver a statement in writing certifying (i) that
this Lease is unmodified and in full force and effect (or, if modified, stating
the nature of such modification); (ii) the date to which the rent and other
charges are paid in advance, if any; (iii) acknowledging that there are not, to
their knowledge, any uncured defaults hereunder or specifying such defaults if
they are claimed; and (iv) such other information as either party may reasonably
request. Any such statement may be conclusively relied upon by any prospective
purchaser or encumbrancer of the Premises. Tenant also agrees to provide the
most current three (3) years of audited financial statements within five (5)
days of a request by Landlord for Landlord's use in financing the Premises with
commercial lenders.

     37.   OPTION TO EXTEND THE LEASE TERM:

           A.  GRANT AND EXERCISE OF OPTION: Landlord hereby grants to Tenant,
upon and subject to the terms and conditions set forth in this paragraph, two
(2) options (the "Options") to extend the Lease Term for an additional term (the
"Option Term"), each Option Term shall be for a period of sixty (60) months.
Each such Option shall be exercised, if at all, by written notice to Landlord no
earlier than the date that is thirty (36) months prior to the Expiration Date
but no later than the date that is thirty (30) months prior to the Expiration
Date. If Tenant exercises the Option, each of the terms, covenants and
conditions of this Lease except this paragraph shall apply during the Option
Term as though the expiration date of the Option Term was the date originally
set forth herein as the Expiration Date, provided that the Base Monthly Rent to
be paid by Tenant during the Option Term shall be the greater of (i) the Base
Monthly Rent applicable to the period immediately prior to the commencement of
the Option Term, or (ii) ninety five percent (95%) of the Fair Market Rental, as
hereinafter defined, for the Premises for the Option Term. Anything contained
herein to the contrary notwithstanding, if Tenant is in monetary or material
non-monetary default under any of the terms, covenants or conditions of this
Lease (after expiration of the applicable cure period) either at the time Tenant
exercises the Option or at any time thereafter prior to the commencement date of
the Option Term, Landlord shall have, in addition to

                                    Page 16
<PAGE>

all of Landlord's other rights and remedies provided in this Lease, the right to
terminate the Option upon notice to Tenant, in which event the expiration date
of this Lease shall be and remain the Expiration Date. As used herein, the term
"Fair Market Rental" for the Premises shall mean the rental and all other
monetary payments including any escalations and adjustments thereto (including
without limitation Consumer Price Indexing) then being obtained for new leases
of space comparable in age and quality to the Premises in the locality of the
Building that Landlord could obtain during the Option Term from a third party
desiring to lease the Premises for the Option Term based upon the current use
and other potential uses of the Premises. The appraisers shall be instructed
that the foregoing five percent (5%) discount off the Fair Market Rental is
intended to reduce comparable rents which include (i) brokerage commissions,
(ii) tenant improvement allowances, and (iii) vacancy costs, to account for the
fact that Landlord will not suffer such costs in the event Tenant exercises its
Option. The appraisers shall also be instructed to first attempt to utilize
comparables based on multi-story buildings, and if no such comparables are
available, to then utilize low-rise steel frame buildings in the Palo Alto,
Menlo Park and Mountain View marketplace.

           B.  DETERMINATION OF FAIR MARKET RENTAL:  If Tenant exercises the
Option, Landlord shall send to Tenant a notice setting forth the Fair Market
Rental for the Premises for the Option Term, on or before the date that is
twelve (12) months prior to the Expiration Date. If Tenant disputes Landlord's
determination of the Fair Market Rental for the Option Term, Tenant shall,
within thirty (30) days after the date of Landlord's notice setting forth the
Fair Market Rental for the Option Term, send to Landlord a notice stating that
Tenant either (i) elects to terminate its exercise of the Option, in which event
the Option shall lapse and this Lease shall terminate on the Expiration Date, or
(ii) disagrees with Landlord's determination of Fair Market Rental for the
Option Term and elects to resolve the disagreement as provided in paragraph
37(C) below. If Tenant does not send to Landlord a notice as provided in the
previous sentence, Landlord's determination of the Fair Market Rental shall be
the basis for determining the Base Monthly Rent to be paid by Tenant hereunder
during the Option Term. If Tenant elects to resolve the disagreement as provided
in paragraph 37(C) below and such procedures shall not have been concluded prior
to the commencement date of the Option Term, Tenant shall pay as Base Monthly
Rent to Landlord the Fair Market Rental as determined by Landlord in the manner
provided above. If the amount of Fair Market Rental as finally determined
pursuant to paragraph 37(C) below is greater than Landlord's determination,
Tenant shall pay to Landlord the difference between the amount paid by Tenant
and the Fair Market Rental as so determined in paragraph 37(C) below within
thirty (30) days after the determination. If the Fair Market Rental as finally
determined in paragraph 37(C) below is less than Landlord's determination, the
difference between the amount paid by Tenant and the Fair Market Rental as so
determined in paragraph 37(C) below shall be credited against the next
installments of rent due from Tenant to Landlord hereunder.

           C.  RESOLUTION OF A DISAGREEMENT OVER THE FAIR MARKET RENTAL:  Any
disagreement regarding the Fair Market Rental shall be resolved as follows:

               1.   Within thirty (30) days after Tenant's response to
Landlord's notice to Tenant of the Fair Market Rental, Landlord and Tenant shall
meet no less than two (2) times, at a mutually agreeable time and place, to
attempt to resolve any such disagreement.

               2.   If within the thirty (30) day period referred to in (i)
above, Landlord and Tenant can not reach agreement as to the Fair Market Rental,
they shall each select one appraiser to determine the Fair Market Rental. Each
such appraiser shall arrive at a determination of the Fair Market Rental and
submit their conclusions to Landlord and Tenant within thirty (30) days after
the expiration of the thirty (30) day consultation period described in (i)
above.

               3.   If only one appraisal is submitted within the requisite time
period, it shall be deemed to be the Fair Market Rental. If both appraisals are
submitted within such time period, and if the two appraisals so submitted differ
by less than ten percent

                                    Page 17
<PAGE>

(10%) of the higher of the two, the average of the two shall be the Fair Market
Rental. If the two appraisals differ by more than ten percent (10%) of the
higher of the two, then the two appraisers shall immediately select a third
appraiser who shall within thirty (30) days after his or her selection make a
determination of the Fair Market Rental and submit such determination to
Landlord and Tenant. This third appraisal will then be averaged with the closer
of the two previous appraisals and the result shall be the Fair Market Rental.

           4.  All appraisers specified pursuant to this paragraph shall be
members of the American Institute of Real Estate Appraisers with not less than
ten (10) years experience appraising office and industrial properties in the
Santa Clara Valley. Each party shall pay the cost of the appraiser selected by
such party and one-half of the cost of the third appraiser.

     38.   OPTIONS:  All Options provided Tenant in this Lease are personal and
granted to original Tenant and any permitted transferee pursuant to paragraph
29(E) of the Lease and are not exercisable by any other third party should
Tenant assign or sublet all or a portion of its rights under this Lease, unless
Landlord consents to permit exercise of any option by any assignee or subtenant,
in Landlord's sole discretion. In the event that Tenant hereunder has any
multiple options to extend this Lease, a later option to extend the Lease cannot
be exercised unless the prior option has been so exercised.

     39.   QUIET ENJOYMENT:  Upon Tenant's faithful and timely performance of
all the terms and covenants of the Lease and except as otherwise provided in
this Lease, Tenant shall quietly have and hold the Premises for the Lease Term
and any extensions thereof.

     40.   BROKERS:  Tenant represents it has not utilized or contacted a real
estate broker or finder with respect to this Lease other than CB Commercial and
Tenant agrees to indemnify and hold Landlord harmless against any claim, cost,
liability or cause of action asserted by any other broker or finder claiming
through Tenant. Landlord agrees to pay the commission to CB Commercial as
provided in a separate agreement between CB Commercial and Landlord.

     41.   LANDLORD'S LIABILITY:  If Tenant should recover a money judgment
against Landlord arising in connection with this Lease, the judgment shall be
satisfied only out of Landlord's interest in the Premises including the
improvements and real property and neither Landlord or any of its partners,
officers, directors, agents, trustees, shareholders or employees shall be liable
personally for any deficiency. And furthermore, Tenant expressly waives any and
all rights to proceed against the individual partners or the officers, directors
or shareholders of any corporate partner, except to the extent of their interest
in said limited partnership.

     42.   AUTHORITY OF PARTIES:  If Landlord or Tenant is a corporation, each
individual executing this Lease on behalf of said corporation represents and
warrants that he is duly authorized to execute and deliver this Lease on behalf
of said corporation, in accordance with a duly adopted resolution of the Board
of Directors of said corporation or in accordance with the by-laws of said
corporation, and that this Lease is binding upon said corporation in accordance
with its terms.

     43.   TRANSPORTATION DEMAND MANAGEMENT PROGRAMS:  Should a government
agency or municipality require Landlord to institute TDM (Transportation Demand
Management) facilities and/or program, Landlord and Tenant hereby agree that the
cost of TDM imposed capital costs required on the Premises, including but not
limited to employee showers, lockers, cafeteria, or lunchroom facilities, shall
be shall be amortized pursuant to paragraph 17 and any ongoing operational costs
or expenses associated with a TDM program, such as an on-site TDM coordinator,
which are required for the Premises shall be paid for by Tenant.

     44.   RIGHT OF FIRST OFFERING TO PURCHASE:  Landlord hereby grants

                                    Page 18
<PAGE>

Tenant a right of first offering to purchase the Premises. Prior to Landlord
offering to sell the Premises to a third party (other than the third parties
with existing rights), Landlord shall give Tenant written notice of such desire
and the terms and other information under which Landlord intends to sell the
Premises. Provided at the time of exercise, Tenant (i) is not in default and
(ii) fully occupies the Premises, Tenant shall have the option, which must be
exercised, if at all, by written notice to Landlord within ten (10) days after
Tenant's receipt of Landlord's notice, to purchase the Premises at the sales
price and terms of sale specified in the notice. In the event Tenant timely
exercises such option to purchase the Premises, Landlord shall sell the Premises
to Tenant, and Tenant shall purchase the Premises from Landlord in accordance
with the price and terms specified in Landlord's notice. Landlord and Tenant
shall, in good faith, attempt to reach agreement on the terms of a mutually
acceptable purchase agreement consistent with the terms set forth in Landlord's
notice within thirty (30) days of Landlord's notice. In the event (i) Landlord
and Tenant are unable to reach agreement on a mutually acceptable purchase
agreement within such thirty (30) day period or (ii) Tenant fails to exercise
Tenant's option within said ten (10) day period, Landlord shall have one hundred
eighty (180) days thereafter to sell the Building at no less than ninety percent
(90%) of the sales price and upon the same or substantially the same other terms
of sale as specified in the notice to Tenant. In the event Landlord fails to
sell the Premises within said one hundred eighty (180) day period or in the
event Landlord proposes to sell the Premises at less than ninety percent (90%)
of the sales price or on other material terms which are more favorable to the
prospective tenant than that proposed to Tenant, Landlord shall be required to
resubmit such offer to Tenant in accordance with this Right of First Offering.

           This Right of First Offering shall automatically terminate, (i) upon
the expiration or sooner termination of the Lease, or (ii) in the event of a
foreclosure or other involuntary transfer of Landlord's interest in the
Premises. Notwithstanding the forgoing, this Right of First Offering shall not
apply to transfers of all or a portion of the Premises to (i) John A. Sobrato
and/or John M. Sobrato (individually and collectively "Sobrato"), and (ii) any
immediate family member of Sobrato, and (iii) any trust established, in whole or
in art, for the benefit of Sobrato and/or any immediate family member of
Sobrato, (iv) any partnership in which Sobrato or any immediate family member,
either directly or indirectly (e.g., through a partnership or corporate entity
or a trust) retains a general partner interest, and/or (v) any corporation under
the control, either directly or indirectly, by Sobrato or any immediate family
member of Sobrato.

     45.   DISPUTE RESOLUTION:  Except for the failure by Tenant to timely pay
the Base Monthly Rent, any controversy, dispute, or claim of whatever nature
arising out of, in connection with, or in relation to the interpretation,
performance or breach of this agreement, including any claim based on contract,
tort, or statute, shall be resolved at the request of any party to this
agreement through a two-step dispute resolution process administered by JAMS or
another judicial and mediation service mutually acceptable to the parties
involving first mediation, followed, if necessary, by final and binding
arbitration administered by and in accordance with the then existing rules and
practice of the judicial and mediation service selected, and judgment upon any
award rendered by the arbitrator(s) may be entered by any State or Federal Court
having jurisdiction thereof.

     46.   MISCELLANEOUS PROVISIONS:

           A.  RENT:  All monetary sums due from Tenant to Landlord under this
Lease, including, without limitation those referred to as "additional rent",
shall be deemed to be rent.

           B.  THIS PARAGRAPH INTENTIONALLY LEFT BLANK:

           C.  PERFORMANCE BY LANDLORD:  If Tenant fails to perform any
obligation required under this Lease or by law or governmental regulation,
Landlord in its sole discretion may without notice and without releasing Tenant
from its obligations hereunder or waiving any rights or remedies, perform such
obligation, in which event

                                    Page 19
<PAGE>

Tenant shall pay Landlord as additional rent all sums paid by Landlord in
connection with such substitute performance including interest as provided in
paragraph 44(D) below within ten (10) days following Landlord's written notice
for such payment.

           D.  INTEREST:  All rent due hereunder, if not paid when due, shall
bear interest at the maximum rate permitted under California law accruing from
the date due until the date paid to Landlord.

           E.  RIGHTS AND REMEDIES:  All rights and remedies hereunder are
cumulative and not alternative to the extent permitted by law and are in
addition to all other rights and remedies in law and in equity.

           F.  SURVIVAL OF INDEMNITIES:  All indemnification, defense, and hold
harmless obligations of Landlord and Tenant under this Lease shall survive the
expiration or sooner termination of the Lease.

           G.  SEVERABILITY:  If any term or provision of this Lease is held
unenforceable or invalid by a court of competent jurisdiction, the remainder of
the Lease shall not be invalidated thereby but shall be enforceable in
accordance with its terms, omitting the invalid or unenforceable term.

           H.  CHOICE OF LAW:  This Lease shall be governed by and construed in
accordance with California law. Venue shall be Santa Clara County.

           I.  TIME:  Time is of the essence hereunder.

           J.  ENTIRE AGREEMENT:  This instrument contains all of the agreements
and conditions made between the parties hereto and may not be modified orally or
in any other manner other than by an agreement in writing signed by all of the
parties hereto or their respective successors in interest.

           K.  REPRESENTATIONS:  Tenant acknowledges that neither Landlord nor
any of its employees or agents have made any agreements, representations,
warranties or promises with respect to the demised Premises or with respect to
present or future rents, expenses, operations, tenancies or any other matter.
Except as herein expressly set forth herein, Tenant relied on no statement of
Landlord or its employee for that purpose.

           L.  HEADINGS:  The headings or titles to the paragraphs of this Lease
are not a part of this Lease and shall have no effect upon the construction or
interpretation of any part thereof.

           M.  EXHIBITS:  All exhibits referred to are attached to this Lease
and incorporated by reference.

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

Landlord: SOBRATO DEVELOPMENT                Tenant: DIALOG INFORMATION
          COMPANIES                                  SERVICES, INC.

a California Limited Partnership             a California Corporation

By: /s/ Signature Illegible                  By: /s/ Signature Illegible
    -----------------------                      -----------------------

Its: Trustee of the General Partner          Its: President

                                    Page 20
<PAGE>

                             Exhibit "A"-Parcel Map


                               [EXHIBIT OMITTED]
<PAGE>

               Exhibit B - Tenancy in Common & Maintenance Agmt

                                                         FILED FOR RECORD
                                                         AT REQUEST OF

When Recorded Return To:
                                                         /s/ Sobrato Development
                                                         JUN 10 3 20 PM '89
John Paul Hanna, Esq.
525 University Avenue, Suite 705
Palo Alto, CA 94301                                      OFFICIAL RECORDS
                                                         SANTA CLARA COUNTY
                                                         LAURIE KAHZ

                  TENANCY IN COMMON AND MAINTENANCE AGREEMENT
            DECLARATION OF COVENANTS, CONDITIONS AND RESTRICTIONS,
                            AND GRANT OF EASEMENTS

     THIS AGREEMENT, DECLARATION AND GRANT, made on the date hereinafter set
forth, by SKYVIEW 2400-EL CAMINO REAL, a California limited partnership
("Skyview"), and SOBRATO DEVELOPMENT COMPANY 850, a California limited
partnership ("Sobrato"), is made with reference to the following facts:

     A.    Skyview owns property located in the City of Mountain View ("City"),
County of Santa Clara, consisting of Lots 3-I, 3-IIA, 3-IIB, 3-IIC, 4A, 4B, 5,
6A, 6B and 7 described on that subdivision map entitled "Tract No. 7813"
("Map"), which map was filed for record in the Office of the Recorder of Santa
  ---
Clara County, California, on the 10th day June, 1986, Book 561 of Maps, pages
1,2,3&4 (the "Skyview Property").
              ----------------

     B.    Sobrato owns Lot 1 described on the Map (the "Sobrato Property").

     C.    Sobrato and Skyview each own an undivided one-half (1/2) interest in
Lot 2 described on the Map. Lot 2 consists of a three (3) level underground
garage ("garage" or "garage property").

     D.    The parties intend to: (1) share use of the garage; (2) provide for
management of the garage; (3) impose upon their respective properties mutually
beneficial protective covenants, conditions and restrictions; and (4) grant
certain reciprocal easements over portions of their respective properties.

     NOW, THEREFORE, Skyview and Sobrato hereby declare that all of the property
described above shall be held, sold, leased, mortgaged, encumbered, rented,
used, occupied, improved and conveyed subject to the following declarations,
limitations, easements, restrictions, covenants, conditions, which are imposed
as equitable servitudes pursuant to a general plan for the development of the
property for the purpose of enhancing and protecting the value and desireability
of the property and every part thereof, and which shall run with the real
property and be binding on Sobrato and Skyview and their successors and assigns,
and on all parties having or acquiring any right, title or interest in or to the
described property or any part thereof, their heirs, successors and assigns, and
shall inure to the benefit of each owner thereof.

                                      -1-
<PAGE>

                                   ARTICLE I

                                    GARAGE

     1.1    CONSTRUCTION:  Sobrato shall construct the garage, at its expense,
pursuant to plans and specifications approved by Sobrato and Skyview and by the
City. Sobrato shall pay all bills incurred in the construction of the garage so
that title to Lot 2 shall be delivered to Sobrato and Skyview free from any lien
claims or encumbrances, together with a fully paid for CLTA title insurance
policy insuring fee title in the owners, free from liens and encumbrances.
Sobrato shall warrant the garage against material defects in design and
construction for a period of one (1) year from the date that notice of
completion is filed and title is transferred in undivided interests to Sobrato
and Skyview, whichever occurs later.

     1.2   MANAGEMENT:  Sobrato (the "managing owner") shall manage the garage,
and may hire a professional management company (the "manager") for this purpose
under a contract entered into after competitive bidding based on bids from two
(2) or more responsible bidders. The term of the contract shall not exceed one
(1) year. The managing owner may delegate any of its duties hereunder to the
manager. Sobrato shall serve as managing owner so long as the parties agree, and
when the owners no longer agree that Sobrato shall be the managing owner, other
arrangements satisfactory to Sobrato and Skyview shall be made.

     1.3   MAINTENANCE:  The managing owner shall be responsible for maintenance
of the garage, with the actual maintenance to be performed by the manager
described in section 1.2.

     1.4   INSURANCE:  The managing owner shall obtain the following insurance
on the garage and the appurtenances thereto:

           A.  CASUALTY:  So-called "fire and extended coverage, all risk"
insurance, with earthquake and flood endorsements, if reasonably available,
insuring the garage against loss for the full replacement value cost thereof,
containing a deductible not exceeding five percent (5%) of the replacement value
of the garage;

           B.  LIABILITY:  Comprehensive general liability insurance insuring
the owners of the garage and their tenants against liability for personal
injury, bodily injury, death, and damage to property occurring or resulting from
an occurrence in, on, or about the garage and its appurtenances, with combined
single limit coverage of Ten Million Dollars ($ 10,000,000); and

           C.  WORKERS' COMPENSATION:  Workers' compensation insurance as
required by statute.

     1.5   CONTRACTS:  The managing owner may enter into contracts including,
without

                                      -2-
<PAGE>

limitation, contracts for management, maintenance and security of the garage.

     1.6   DESTRUCTION AND REBUILDING:  If the garage improvements are
substantially damaged (more than fifty percent (50%) destroyed) or destroyed by
fire, earthquake or other catastrophe, the owners shall decide within a maximum
of three (3) months after the catastrophe whether to rebuild. If either owner
decides not to continue operations and desires not to rebuild the garage, and
the other owner desires or is required by the terms of any lease or mortgage
affecting the garage to rebuild the garage and to continue operations, the owner
deciding not to rebuild and continue operations shall remove all rubble from its
property and leave its lot landscaped according to a standard comparable to the
standard existing in the project just prior to the catastrophe, and the owner
electing to rebuild and continue operations shall be entitled to receive all of
the proceeds from the insurance policy covering the garage and to use that
proceeds to reconstruct the garage or such portion thereof as is necessary to
permit that owner to continue operations. Damage resulting in less than fifty
percent (50%) destruction shall be repaired in all cases.

     1.7   CONDEMNATION:  If in the event of the taking of all or any portion of
the garage, the proceeds of condemnation shall be distributed equally to the
owners subject to the rights of their mortgagees, if any.

     1.8   SECURITY:  The managing owner shall acquire and install the
surveillance equipment (television cameras) for maintenance of security in the
garage and the cost thereof shall be included in operating costs to be shared as
provided in section 1.9. Skyview and Sobrato shall each, at their own expense,
construct one (1) monitoring station for their respective use. The stations
shall be linked together for purposes of communication. Each party shall provide
its own monitoring and security guards, if desired, at its own expense. No owner
of the garage nor any of their agents, employees or tenants shall be liable to
any other owner or its agents, employees or tenants for failing to provide
security for the garage.

     1.9   COST SHARING:  Except as provided in section 1.8, all costs of
operation, maintenance, management, taxes, and insurance premiums relating to
the garage ("garage expenses") shall be borne by the fee title owner(s) of Lot 2
in proportion to their interest in Lot 2. The managing owner, in its reasonable
discretion, shall determine and cause to be collected from said owners of Lot 2,
reasonable reserves for capital improvements and extraordinary garage expenses.
The managing owner also shall prepare and deliver to the owners of Lot 2, not
less than forty-five (45) nor more than sixty (60) days before the beginning of
the calendar year a report consisting of: (1) estimated annual revenue and
garage expenses for the ensuing calendar year; (b) the

                                      -3-
<PAGE>

amount of the total cash reserves currently available; (c) the actual garage
expenses for the preceding calendar year; (d) the total garage assessment paid
by each owner during the preceding calendar year; and (e) the amount of
estimated monthly assessments to be paid by each owner during the ensuing
calendar year. If the report indicates that the actual garage expenses, plus
reserves, for any particular calendar year were not equal to the garage
assessments payable for such year by the owners of Lot 2 the difference shall be
paid by or to the managing owner within ten (10) days of the managing owner's
report, to the end that the managing owner shall receive from each owner of Lot
2 each year that owner's proportionate share of actual garage expenses, plus
reserves. The managing owner shall make available for inspection by any owner of
Lot 2, or its representative, at the property during normal business hours, the
books, records, and invoices supporting the garage assessments and payments
demanded for garage assessments. If any such inspection should disclose a
discrepancy of five percent (5%) or more, the managing owner shall pay all cost
of the inspection.

     1.10  TOWING OF AUTOMOBILES:  Certain parking spaces in the garage are
reserved for exclusive use of certain persons. The managing owner or the manager
are authorized to have any automobiles which are illegally or improperly parked
anywhere in the project towed at the expense of the owner of said vehicle. The
managing owner may hire any towing company to tow such cars.

     1.11  INCOME FROM PARKING FEES:  All income from fees charged to the public
for use of the garage shall be used for current expenses of maintenance,
operation, and insurance, and any surplus shall be deposited to a reserve
account for capital improvements and emergencies.

     1.12  CAPITAL COSTS:  In the event any extraordinary expenses or
expenditures for capital improvements are required, and the proceeds of current
operations and reserves are insufficient for such purpose, the managing owner
may require capital contributions to be made by the owners of Lot 2 in the same
ratio as provided for cost sharing in section 1.9.

     1.13  MANAGING OWNER:  The managing owner shall not be personally liable
for ordinary mistakes in judgment or for any conduct in his capacity as managing
owner except for active negligence or willful misconduct in managing the
operation and maintenance of the garage, or in selecting and supervising a
manager for the garage.

     1.14  PAYMENT OF COSTS:  On the first day of each calendar month the owners
of Lot 2 shall pay their respective shares of the monthly garage expenses upon
receipt of the monthly assessment from the manager. Any assessment not paid
within fifteen (15) days after the due date (as specified in the assessment)
shall be delinquent, shall bear

                                      -4-
<PAGE>

interest at the rate of twelve percent (12%) per annum from the due date until
paid, and shall incur a late payment penalty in the amount of ten percent (10%)
of the assessment. The owners of Lot 2 agree that a lien with a private power of
sale for a delinquent assessment, including interest, penalty and attorney's
fees, is hereby granted against the interest of said delinquent owner in Lot 2,
and that the lien may be enforced by sale of the delinquent owner's interest in
Lot 2 by the managing owner pursuant to the provisions of section 2924-2924h of
the California Civil Code applicable to the exercise of powers of sale in
mortgages and deeds of trust, or in any other manner permitted by law.

     1.15  WAIVER OF PARTITION:  Each party forever waives the right to bring
any partition action to divide lot 2 under Title 10.5 of Part II of the
California Code of Civil Procedure, or any successor partition statutes thereto.

                                  ARTICLE II

                                   EASEMENTS

     2.1   EASEMENTS FOR INGRESS AND EGRESS:  Skyview hereby grants to Sobrato
for the benefit of the Sobrato Property as the dominant tenement easements for
ingress and egress over Lot 3-I as the servient tenement and Sobrato hereby
grants to Skyview for the benefit of the Skyview Property as the dominant
tenement easements for ingress and egress over Lot 1 as the servient tenement.
Said easements are for pedestrian traffic only over the walkways and other
access routes located on the open space areas of said lots (those areas not
occupied by buildings).

     2.2   GARAGE PARKING AND USE:  The owners of Lot 2, their occupants,
tenants and invitees shall have rights of ingress and egress to and from and
parking within the garage (except in spaces reserved for the exclusive use of
the owners and occupants as provided in section 2.3), and to the extent required
for vehicular access to the garage, easements for ingress and egress over that
portion of Lots 1 and 3-I within paved driveways and garage entrances and exits.

     2.3   EXCLUSIVE USE OF PARKING SPACES:  Certain parking spaces in the
garage are reserved for the exclusive use of certain persons as provided in
Exhibit "A" attached hereto and incorporated by reference herein. In the event
that any owner of Lot 2 fails to pay its share of monthly garage expenses
("delinquency"), and should the delinquency continue for one hundred twenty
(120) days, all of the rights of said owner of Lot 2 and its successor, members,
tenants, and all other persons claiming rights in Lot 2 through said owner shall
be suspended and the manager shall be authorized to prevent access to the garage
and to the reserved spaces by all such parties. In the event that the owner of a
condominium, who belongs to a condominium association which is an owner of Lot
2,

                                      -5-
<PAGE>

fails to pay any amounts payable to the association in connection with the use
of the garage for a period of ten (10) days after the due date of such payment,
that association may immediately file a lien against the condminium interest of
the delinquent condominium owner pursuant to covenants, conditions and
restrictions encumbering the condominium, and may notify the manager of the
garage to suspend the parking privileges of the delinquent condominium owner.
Once parking privileges are suspended with respect to a person, the manager of
the garage may blockade the space assigned to such person to prevent its being
used until the delinquency is cured.

     2.4   DRAINAGE:  Reciprocal drainage and sewer facility easements are
granted over Lots 1, 2 and 3-I as a benefit and burden on each of these lots for
the flow of surface water, and for installation, inspection, maintenance,
repair, replacement, and removal of storm sewer and sanitary sewer facilities.
Said easements are limited to the open space areas of said lots which are not
occupied by buildings.

     2.5   UTILITIES:  Reciprocal utility easements are granted over Lots 1, 2
and 3-I as a benefit and burden on each of these lots for installation,
inspection, maintenance, repair, replacement and removal of water, electric,
gas, telephone, television and other utility facilities. Said reciprocal
easements are limited to the open space areas of said lots which are not
occupied by buildings.

     2.6   ENCROACHMENT EASEMENTS:  Reciprocal encroachment easements are
granted over Lots 1, 2 and 3-I as a benefit and burden on each of these lots for
purposes of accommodating any encroachment of foundations, and overhangs of
exterior walls, windows, and roofs which are built in accordance with the
original design, plans and specifications of the parties, or due to minor
engineering errors, minor errors in original construction, settlement or
shifting of the buildings, or similar clauses. There shall be valid easement for
the maintenance of said encroachments as long as they shall exist and the rights
and obligations of owner shall not be altered in any way by said encroachment,
settling or shifting. In the event a structure is partially or totally
destroyed, and then repaired or rebuilt, the owners of each adjoining lot agree
that minor encroachments over adjoining lots shall be permitted and there shall
be valid easements for the maintenance of said encroachments so long as they
shall exist.

     2.8   VIEW EASEMENT:  A view easement is granted over Lot 1 as the servient
tenement in favor of Lots 3-I, 3-IIA, 3-IIB, 3-IIC, 4A, 4B, 5, 6A, 6B and 7 as
the dominant tenements for preservation of the view over Lot 1 that will exist
upon completion of the proposed seven (7) story office building upon Lot 1 in
accordance with the final plans approved by the City. The purpose of this view
easement is to prohibit

                                      -6-
<PAGE>

additional construction on Lot 1 which would increase the height or mass of the
seven (7) story office building or which would take place within the open space
area of Lot 1.

     2.9   STRUCTURAL REPAIR EASEMENTS:  Reciprocal structural repair easements
are granted over Lots 1, 2, 3-I, 3-IIA, 3-IIB, 3-IIC, 4A, 4B, 5, 6A, 6B and 7 as
a benefit and burden on each of these lots for allowing such access over any
adjoining lot subject to this easement as may be reasonably necessary in order
to make any structural repairs to an improvement on a lot, provided that the
owner making such improvements or repairs to its lot shall fully reimburse the
owner of the adjoining lot for any damages thereto (including business
interruption or injuries to persons) resulting from the exercise of the easement
rights described herein.

     2.10  EASEMENTS TO ACCOMPANY CONVEYANCE OF LOT:  The easements described in
this Article II are permanent and appurtenant to the respective dominant
tenements, and shall automatically accompany the conveyance of any lot, even
though the description in the instrument of conveyance may refer only to the fee
title to the lot.

                                  ARTICLE III

                               USE RESTRICTIONS

     3.1   NUISANCES:  No noxious, illegal, or seriously offensive activities
shall be carried on upon any lot, or in any part of the property, nor shall
anything be done thereon which may be or may violate any law, rule or regulation
of any applicable governmental entity or any private covenant, condition, or
restriction affecting the garage become a nuisance to or which may in any way
interfere with the quiet enjoyment of each of the owners of his respective lot.

     3.2   LANDSCAPING:  Lots 1 and 3-I shall be landscaped in accordance with
plans and specifications submitted to and approved by the City. Landscaping
shall be installed within ninety (90) days of completion of buildings. After
installation, landscaping shall be maintained in a sightly and well-kept
condition by the owner, lessee, licensee or other occupant of the lot or its
agent, at its expense. All landscaped areas shall be irrigated with a system
designed for automatic operation.

     3.3   GROUND MAINTENANCE:

           A.  Grass, hedges, shrubs, vines and mass planting of any type on
each lot shall be kept trimmed and shall at regular intervals be mowed, trimmed
and cut so as to maintain the same in a neat and attractive manner. Trees,
shrubs, vines and plants which die shall be promptly removed and replaced with
living plants of like kind and quality.

           B.  No weeds, vegetation, rubbish, debris, garbage, objects, waste
materials, or materials of any kind whatsoever shall be placed or permitted to

                                      -7-
<PAGE>

accumulate upon any portion of a lot, which would render it unsanitary,
unsightly, offensive, or detrimental to any property in the vicinity thereof or
to the occupants of any such property in such vicinity.

           C.  No building material of any kind or character shall be placed or
stored upon any lot so as to be open to view by the public or neighbors, unless
such material will be used and is used within three (3) months for the
construction of buildings or structures upon the lot upon which the material is
stored.

     3.4   EXTERIOR LIGHT FIXTURES:  No exterior lighting fixture shall be
installed on any lot without adequate and proper shielding of the source of the
light. No exterior lighting fixtures shall be installed that may become a
nuisance to adjacent lots subject to his Declaration. Office lighting on Lot 1
shall be kept at a minimum during periods when the offices are not occupied to
minimize glare affecting the residential areas of the property.

     3.5   EXCAVATIONS:  No excavation for stone, gravel, sand, dirt or earth
shall be made on any portion of a lot, except for the construction of buildings,
walls, fences, foundations, structures, landscaping, swimming pools and other
improvements, plans and specifications for which excavations have been approved
by the City; provided, however, that the owners reserve the right to excavate,
fill and grade on any lot or on any portion thereof, or to do such other work of
improvement thereon as may be necessary to the construction and completion of
public improvements.

     3.6   CLOTHES LINES:  No exterior clothes lines shall be erected or
maintained and there shall be no outside laundering or drying of clothes. No
draping of towels, carpets, or laundry over railings shall be allowed.

     3.7   BALCONY STORAGE:  No storage on balconies shall be permitted. No
balcony shall be enclosed.

     3.8   PETS:  No pets shall be allowed in Lot 1. No pets shall be allowed in
Lot 3-I unless on a leash.

                                  ARTICLE IV

                                    GENERAL

     4.1   ENFORCEMENT:  Any owner shall have the right to enforce, by any
proceeding at law or in equity, all restrictions, conditions, covenants,
reservations, liens, and charges now or hereafter imposed by the provisions of
this Declaration, and in such action shall be entitled to recover reasonable
attorneys' fees as are ordered by Court. Failure by any owner to enforce any
covenant or restriction herein contained shall in no event be deemed a waiver of
the right to do so thereafter. Any owner alleged to be in

                                      -8-
<PAGE>

default of any provision hereof shall be given ten (10) days to cure any alleged
default before legal or disciplinary action may be taken. The owner(s) of both
properties and their tenants shall have the right to enforce or require
enforcement of this Agreement. This Agreement shall be binding upon and
enforceable against owners and all tenants of the owner(s).

     4.2   RECORDS:  The managing owner shall keep accurate and complete books,
ledgers and records regarding the management and maintenance of the garage,
which shall be open to inspection at all times by all owners on reasonable
notice. The managing owner shall render accountings as often as requested by the
other owner(s) and shall provide a complete annual accounting and report no
later than sixty (60) days after the close of the calendar year.

     4.3  TAXES:  The managing owner shall pay the property taxes promptly prior
to delinquency of installments.

     4.4  TERM:  The covenants and restrictions of this Declaration shall run
with and bind the Sobrato, Skyview and garage properties, and shall inure to the
benefit of and shall be enforceable by the owner of any such property subject to
this Declaration, its respective legal representatives, heirs, successors and
assigns, for a term of fifty (50) years from the date this Declaration is
recorded, after which time they shall be automatically extended for successive
periods of ten (10) years, unless an instrument in writing, signed by all of the
then owners of the lots, has been recorded within the year preceding the
beginning of each successive period of ten (10) years, agreeing to change said
covenants and restrictions in whole or in part, or to terminate the same.

     4.5   NOTICES:  Any notice permitted or required by this Declaration may be
delivered either personally or by mail. If delivery is by mail, it shall be
deemed to have been delivered seventy-two (72) hours after a copy of the same
has been deposited in the United States mail, first class or registered, postage
prepaid, addressed to the person to be notified at the current address given by
such person to the managing owner. Copies of any notices delivered hereunder
regarding any alleged default or other matters specifically requested shall be
given to any requesting lender that holds a first deed of trust against any lot
on the Map at the address that the lender has provided the managing owner.

     4.6   INVALIDITY OF ANY PROVISION:  Should any provision or portion hereof
be declared invalid or in conflict with any law of the jurisdiction where this
project is situated, the validity of all other provisions and portions hereof
shall remain unaffected and in full force and effect.

                                      -9-
<PAGE>

     4.7   SUCCESSORS IN INTEREST:  This Declaration and the covenants,
conditions, easements and agreements contained herein shall be binding upon and
inure to the benefit of the parties and their permitted assigns and permitted
successors in interest, including one or more owners' associations which any of
the owners may create and to which any of the owners may assign all or a portion
of their rights and obligations hereunder. In the event that Skyview assigns it
rights and obligations to one or more owners' associations or owners, said
associations and/or owners shall designate a single representative who shall
exercise the rights of the owner of a one-half (1/2) undivided interest in Lot 2
on behalf of the individuals and associations who collectively own the one-half
(1/2) interest initially owned by Skyview. The rights and duties hereunder are
appurtenant to the respective properties and any transfer of a fee interest in
the property encumbered by this Agreement (other than a lease or a transfer for
security purposes only) transfers the rights and duties. From and after the date
of such transfer, the transferor shall have no further rights or duties
hereunder provided that the transferor shall remain liable for any breach of its
duties hereunder that occurred before the transfer.

     4.8   RECIPROCAL INDEMNITY PROVISIONS:  Sobrato and Skyview each agree on
behalf of themselves and their respective agents, tenants, employees,
successors, and assigns, to forever release each other and their respective
agents, tenants, employees, successors, and assigns from all damages, claims,
causes of action, costs, liabilities, attorneys' fees, and expenses which are to
be covered by the insurance to be carried under this agreement or which are
actually compensated by insurance. Each party shall cause any insurance policy
carried by it to contain a valid waiver by the insurer of its right of
subrogation against all other parties thereto and said party's agents, tenants,
employees, successors, and assigns. Except as expressly set forth to the
contrary herein, Sobrato and Skyview each agree to hold the other party and its
agents, employees and contractors harmless from claims for injury and/or damage
arising out of their active negligence or wilfull misconduct.

     4.9   AMENDMENTS:  This Declaration may be amended by unanimous vote of the
owners of the property subject hereto. The owners agree to approve and adopt all
amendments reasonably required by the City of Mountain View and the Department
of Real Estate of the State of California. The provisions of section 2.3
pertaining to the exclusive use of certain parking spaces for certain persons
(as provided in Exhibit "A" attached hereto and incorporated by reference
herein) shall not be amended or revoked without the express written consent of
the City of Mountain View. Any amendment must

                                     -10-
<PAGE>

be recorded in the Recorder's Office of the County of Santa Clara. No amendment
shall adversely affect the rights of the holder of any mortgage of record prior
to the recordation of such amendment.

     4.10  COOPERATION:  Each party agrees to cooperate in making any revisions
to this Agreement that may be requested by any lender that holds or will hold a
first deed of trust on any lot shown on the Map, provided such revisions do not
materially affect any rights or duties hereunder.

SKYVIEW 2400-EL CAMINO REAL             SOBRATO DEVELOPMENT COMPANY 850
A California Limited Partnership        A California Limited Partnership

By: /s/ Walter J. Harrington            By: /s/ John Michael Sobrato
    ------------------------                ------------------------------------
    Walter J. Harrington                    John Michael Sobrato, A General
                                            Partner

                                        By: /s/ Robert Granum II
                                            ------------------------------------
                                            Robert Granum II, A General Partner

                                        By: /s/ John A. Sobrato
                                            ------------------------------------
                                            John A. Sobrato as Trustee for the
                                            John A. Sobrato and Susan A. Sobrato
                                            1979 Revocable Trust, A General
                                            Partner

DATED: JUNE 9, 1986

                                     -11-
<PAGE>

STATE OF CALIFORNIA      )      MARY K. FRENCH
                         )ss.   NOTARY PUBLIC-CALIFORNIA
COUNTY OF Santa Clara    )      SANTA CLARA COUNTY
                                My Comm. Expires July 31, 1988

     On June 9, 1986, before me, the undersigned, a Notary Public in and for
said State, personally appeared Walter J. Harrington, personally known to me (or
proved to me on the basis of satisfactory evidence) to be the person that
executed this instrument, on behalf of the partnership, and acknowledged to me
that the partnership executed it.

     IN WITNESS WHEREOF I have hereunto set my hand and affixed my official seal
in the County of Santa Clara the day and year in this certificate first above
written.

                                  /s/ Mary K. French
                                  _____________________________
                                  Notary Public, State of California

STATE OF CALIFORNIA      )      MARY K. FRENCH
                         )ss.   NOTARY PUBLIC-CALIFORNIA
COUNTY OF Santa Clara    )      SANTA CLARA COUNTY
                                My Comm. Expires July 31, 1988

     On June 9, 1986, before me, the undersigned, a Notary Public in and for
said State, personally appeared John Michael Sobrato, personally known to me (or
proved to me on the basis of satisfactory evidence) to be the person that
executed this instrument, on behalf of the partnership, and acknowledged to me
that the partnership executed it.

     IN WITNESS WHEREOF I have hereunto set my hand and affixed my official seal
in the County of Santa Clara the day and year in this certificate first above
written.

                              /s/  Mary K. French
                                   ____________________________
Notary Public, State of California

STATE OF CALIFORNIA       )      MARY K. FRENCH
                          )ss.   NOTARY PUBLIC-CALIFORNIA
COUNTY OF Santa Clara)    )      SANTA CLARA COUNTY
                                 My Comm. Expires July 31, 1988

     On June 9, 1986, before me, the undersigned, a Notary Public in and for
said State, personally appeared Robert Granum II, personally known to me (or
proved to me on the basis of satisfactory evidence) to be the person that
executed this instrument, on behalf of the partnership, and acknowledged to me
that the partnership executed it.

     IN WITNESS WHEREOF I have hereunto set my hand and affixed my official seal
in the County of Santa Clara the day and year in this certificate first above
written.

                                    /s/ Mary K. French
                                    ____________________________
                                    Notary Public, State of California

                                      -12-
<PAGE>

STATE OF CALIFORNIA      )
                         )ss.
COUNTY OF Santa Clara    )

     On June 9, 1986, before me, the undersigned, a Notary Public in and for
said State, personally appeared John A. Sobrato, Trustee, personally known to me
(or proved to me on the basis of satisfactory evidence) to be the person that
executed this instrument, on behalf of the partnership, and acknowledged to me
that the partnership executed it.

     IN WITNESS WHEREOF I have hereunto set my hand and affixed my official seal
in the County of Santa Clara the day and year in this certificate first above
written.


                                    /s/ Mary K. French
                                    __________________________________
                                    Notary Public, State of California


                                    MARY K. FRENCH
                                    NOTARY PUBLIC-CALIFORNIA
                                    SANTA CLARA COUNTY
                                    My Comm. Expires July 31, 1988

                                      -13-
<PAGE>

                  TENANCY IN COMMON AND MAINTENANCE AGREEMENT,
             DECLARATION OF COVENANTS, CONDITIONS AND RESTRICTIONS,
                             AND GRANT OF EASEMENTS

                                  EXHIBIT "A"

                                    PARKING

Two hundred sixty-six (266) parking spaces in the garage (Lot 2) are reserved
for the exclusive use of the owners and occupants of Lots 4A, 5, 6A, and 7. The
blocks of spaces identified in the three (3) pages attached hereto as Exhibit
"A-1" are as follows:


                         No. of
Lot No.                  Parking Spaces           Level
-------                  --------------           -----

     4A                       96                  B & C
     5                        37                  A
     6A                       96                  B & C
     7                        37                  A

Declarant and the owners of Lots 4A, 5, 6A, and 7 hereby specifically reserve
the right at any time in the future to make specific assignments of parking
spaces within the block of spaces hereby assigned to a particular lot to the
condominium owners within each lot in accordance with a condominium declaration
and condominium plan to be filed of record.

Sixty (60) spaces located in the garage (Lot 2) are reserved for the exclusive
use of the owner(s), visitors and occupants of Lot 1 all of the time (24 hours
per day). The block of sixty (60) spaces are identified on Exhibit "A-2"
attached hereto.

An additional four hundred (400) parking spaces within the garage, which spaces
are identified on the three (3) pages attached hereto as Exhibit "A-3" attached
hereto, may be used by the owners, visitors and occupants of Lots 3-IIA, 3-IIB,
and 3-IIC, 4A, 5, 6A, and 7, between the hours of 6:00 P.M. and 7:30 A.M. on
business days, and at any time on weekends and holidays, which use will be
shared with the owner/occupants of Lot 1 during the same time. Said four hundred
(400) spaces are exclusively reserved for the use of the owner(s), visitors and
occupant(s) of Lot 1 between 7:30 A.M. and 6:00 P.M. on business days.
Prohibition of resident parking in these spaces during such hours is to be
strictly enforced if parking congestion occurs on surrounding streets or
properties which results from this project, as determined by the City of
Mountain View.

The four hundred sixty (460) total spaces provided for the use of Lot 1 owners,
visitors and occupants as provided above, are to be available at no charge (in
addition to rental and fees paid under the applicable lease or leases) to the
occupants of the office building on Lot 1.

All of the parking spaces located within Lot 3-1 are reserved for use by owners
and occupants of Lots 3-I, 3-IIA, 3-IIB and 3-IIC and 4A, 5, 6A and 7, and shall
be under the control of Skyview until conveyance of Lot 3-I to the owners of
Lots 4A, 5, 6A, and 7, or the condominium association at which time control
shall be assumed by the condominium association(s) created to manage Lots 4A, 5,
6A, and 7.
<PAGE>

                               [EXHIBIT OMITTED]
<PAGE>

                               [EXHIBIT OMITTED]
<PAGE>

                               [EXHIBIT OMITTED]
<PAGE>

                               [EXHIBIT OMITTED]
<PAGE>

                               [EXHIBIT OMITTED]
<PAGE>

                                   EXHIBIT B

                               SUBLEASED PREMISES
<PAGE>

                               [EXHIBIT OMITTED]
<PAGE>

                                   EXHIBIT C

                                COMMON USE AREAS
<PAGE>

                               [EXHIBIT OMITTED]
<PAGE>

                                   EXHIBIT D

                          FIFTH FLOOR EXPANSION SPACE
<PAGE>

                               [EXHIBIT OMITTED]
<PAGE>

                                   EXHIBIT E

                                  WORK LETTER

1.   SUBLESSEE'S INITIAL IMPROVEMENTS. Sublessee shall construct, furnish or
install within the Subleased Premises, at its sole cost and expense, in
compliance with its obligations under the Master Lease and the Sublease, all
improvements, equipment or fixtures that are necessary for Sublessee's use and
occupancy of the Premises (the "Sublessee's Initial Improvements"). The
construction, furnishing and installation of Sublessee's Initial Improvements,
is referred to herein as the "Improvement Work". The Improvement Work shall be
performed in accordance with the following provisions:

     a.   Sublessee will be responsible for delivery to Sublessee of the final
space plans, the basic engineering information and the final working drawings
and specifications with respect to the Improvement Work (collectively,
"Sublessee's Final Plans"). Sublessee shall cause all Sublessee's Final Plans to
be prepared by licensed architects, and where appropriate, licensed mechanical,
electrical and structural engineers.

     b.   Sublessee's Final Plans shall be subject to Sublessor's approval,
which approval shall not be unreasonably withheld. Sublessor shall approve or
reasonably disapprove of the same within seven (7) days of Sublessor's receipt
thereof. If Sublessor disapproves Sublessee's Final Plans, or any portion
thereof, Sublessor shall promptly notify Sublessee thereof and of the revisions
that Sublessor reasonably requires in order to obtain Sublessor's approval. As
promptly as reasonably possible thereafter, but in no event later than seven (7)
days after Sublessor's notice, Sublessee shall submit to Sublessor plans and
specifications incorporating the revisions reasonably required by Sublessor.
Said revisions shall be subject to Sublessor's approval, which shall not be
unreasonably withheld. This procedure shall be repeated until Sublessee's Final
Plans are finally approved by Sublessor and written approval has been received
by Sublessee. The final plans and specifications approved by Sublessor, shall be
referred to as the "Approved Plans".

     c.   Sublessee shall diligently obtain all building and other permits,
licenses and other approvals (collectively, "Permits") necessary to construct
the Improvement Work in compliance with all applicable laws, rules, codes,
standards and regulations (collectively, "Applicable Laws") prior to the
commencement of such work. Sublessee's Initial Improvements shall be diligently
constructed in compliance with the Approved Plans, with all of the terms and
conditions of the Master Lease and Sublease and with all Applicable Laws.

     d.   Prior to commencing construction, Sublessee shall deliver to Sublessor
evidence of insurance as called for hereinbelow and executed copies of the
applicable Permits for such work.

     e.   After final approval of the Approved Plans by Master Lessor and
Sublessor, Sublessee shall proceed promptly to commence performance of the
Improvement Work. Sublessee's contractors and subcontractors shall be acceptable
to and approved in writing by Sublessor, which approval shall not be
unreasonably withheld or delayed, except that Sublessee
<PAGE>

hereby agrees to use Newcomb Mechanical and Access Electric for its HVAC and
electrical contractors, respectively.

     f.   Sublessee shall hire its own general contractor ("Contractor") to
complete Sublessee's Initial Improvements, which Contractor shall provide labor
and materials bond(s) reasonably satisfactory to Sublessor and carry insurance
coverage in an amount and form and issued by a carrier reasonably satisfactory
to Sublessor, endorsed to show Sublessor as an additional insured. Sublessee
shall furnish to Sublessor a copy of the executed contract between Sublessee and
Contractor covering all of Sublessee's obligations under this EXHIBIT E.

     g.   Sublessor shall have the right to post in a conspicuous location on
Sublessee's Premises, as well as record with the county recorder, a Notice of
Nonresponsibility.

     h.   Sublessee shall, upon completion of its work, submit to Sublessor two
(2) complete sets of plans (one (1) reproducible) and specifications covering
all of the Improvement Work, including architectural, electrical, and plumbing,
as built.

2.   EVIDENCE OF COMPLETION OF IMPROVEMENT WORK. Upon the completion of the
Improvement Work, Sublessee shall:

     a.   Submit to Sublessor a detailed breakdown of Sublessee's final and
total construction costs, together with receipted evidence showing payment
thereof, satisfactory to Sublessor.

     b.   Submit to Sublessor certifications from Contractor and Sublessee's
architect that the Improvement Work has been substantially completed in
accordance with the Approved Plans.

     c.   Submit to Sublessor copies of final lien releases from all contractors
and subcontractors furnishing labor or services.

     d.   Submit to Sublessor all evidence reasonably available from
governmental authorities showing compliance with any and all other laws, orders
and regulations of any and all governmental authorities having jurisdiction over
the Subleased Premises, including, without limitation, authorization for
physical occupancy of the Subleased Premises.

     d.   Submit to Sublessor the as-built plans and specifications referred to
above.

3.   SUBLESSEE IMPROVEMENT ALLOWANCE. Subject to Sublessee's satisfaction of the
requirements of this PARAGRAPH 3, Sublessor shall provide Sublessee with a cash
tenant improvement allowance (the "Sublessee Improvement Allowance") in an
amount of up to Five Dollars ($5.00) per rentable square foot for the Subleased
Premises, which may be applied to payments in respect of architectural and
engineering fees, consultants, legal fees, moving expenses, equipment or
communication requirements and hard costs of construction in connection with the
Improvement Work.
<PAGE>

     a.   Sublessor shall make payment to Sublessee of an amount up to the
amount of the Sublessee Improvement Allowance due Sublessee, provided that, (i)
no default exists under the Sublease, (ii) no lien has been filed with respect
to the Improvement Work that has not been released, (iii) Sublessee is in
compliance with all Permits, (iv) all insurance required hereunder, under the
Master Lease and under the Sublease, is in full force and effect and (v)
Sublessee has submitted to Sublessor all items required pursuant to PARAGRAPH 2
above. Notwithstanding the foregoing, in the event that Sublessor withholds
payment of the Sublessee Improvement Allowance as a result of a default existing
under the Sublease, Sublessor shall pay to Sublessee the Sublessee Improvement
Allowance promptly after Sublessee has cured such default.

     b.   Sublessor shall not be obligated to make payments in excess of the
Sublessee Improvement Allowance. Sublessee shall bear and pay any and all costs
of the Improvement Work in excess of the Sublessee Improvement Allowance.