<PAGE>
 
                                                                   EXHIBIT 10.10



                             BERNAL CORPORATE PARK
                             ---------------------

                                SYCAMORE PLAZA I
                                ----------------


                                  OFFICE LEASE

                                    BETWEEN

                           PATRICIAN ASSOCIATES, INC.

                                  ("LANDLORD")


                                      AND


                                DOCUMENTUM, INC.

                                   ("TENANT")
<PAGE>
 
                               TABLE OF CONTENTS
                               -----------------


<TABLE> 
<CAPTION> 
ARTICLE                                                       PAGE
-------                                                       ----
<S>                                                            <C> 

1    TERM....................................................... 2

2    POSSESSION................................................. 2

3    BASIC RENT................................................. 4

4    RENTAL ADJUSTMENT.......................................... 5

5    SECURITY DEPOSIT........................................... 9

6    USE........................................................ 10

7    NOTICES.................................................... 12

8    BROKERS.................................................... 12

9    HOLDING OVER............................................... 12

10   TAXES ON TENANT'S PROPERTY................................. 13

11   CONDITION OF PREMISES...................................... 13

12   ALTERATIONS................................................ 14

13   REPAIRS.................................................... 15

14   LIENS...................................................... 16

15   ENTRY BY LANDLORD.......................................... 16

16   UTILITIES AND SERVICES..................................... 17

17   BANKRUPTCY................................................. 18

18   INDEMNIFICATION............................................ 18

19   DAMAGE TO TENANT'S PROPERTY................................ 19

20   INSURANCE.................................................. 19
</TABLE>

                                       i
<PAGE>
 
<TABLE>
<S>                                                             <C>

21   DAMAGE OR DESTRUCTION.....................................  21

22   EMINENT DOMAIN............................................  23

23   DEFAULTS AND REMEDIES.....................................  23

24   ASSIGNMENT AND SUBLETTING.................................  25

25   SUBORDINATION.............................................  27

26   ESTOPPEL CERTIFICATE......................................  28

27   SIGNAGE...................................................  29

28   RULES AND REGULATIONS.....................................  30

29   CONFLICT OF LAWS..........................................  30

30   SUCCESSORS AND ASSIGNS....................................  30

31   SURRENDER OF PREMISES.....................................  30

32   ATTORNEYS' FEES...........................................  30

33   PERFORMANCE BY TENANT.....................................  30

34   MORTGAGEE PROTECTION......................................  31

35   DEFINITION OF LANDLORD....................................  31

36   WAIVER....................................................  32

37   IDENTIFICATION OF TENANT..................................  32

38   PARKING...................................................  32

39   TERMS AND HEADINGS........................................  33

40   EXAMINATION OF LEASE......................................  33

41   TIME......................................................  33

42   PRIOR AGREEMENT: AMENDMENTS...............................  33

43   SEPARABILITY..............................................  33
</TABLE>

                                      ii
<PAGE>
 
<TABLE>
<S>                                                              <C>
44   RECORDING.................................................. 34

45   CONSENTS................................................... 34

46   LIMITATION ON LIABILITY.................................... 34

47   RIDERS..................................................... 35

48   EXHIBITS................................................... 35

49   MODIFICATION FOR LENDER.................................... 35

50   WAIVER OF LIEN RIGHTS...................................... 35

51   OPTION TO EXTEND........................................... 36

52   LANDLORD'S CONDITION....................................... 37
</TABLE>

                                      iii
<PAGE>
 
                                LIST OF EXHIBITS
                                ----------------



EXHIBIT A-1             The Premises

EXHIBIT A-2             The Project

EXHIBIT B               Work Letter Agreement

EXHIBIT C               Standards for Utilities and Services

EXHIBIT D               Rules and Regulations

EXHIBIT E               Parking Rules and Regulations

EXHIBIT F               Form of Tenant's Letter of Credit

EXHIBIT G               Schedule of Tenant's Leasehold Interest Value

EXHIBIT H               Subordination, Non-Disturbance and Attornment Agreement

                                      iv
<PAGE>
 
                             BERNAL CORPORATE PARK
                               SYCAMORE  PLAZA I


          THIS LEASE is made as of June 22, 1998 by and between PATRICIAN
ASSOCIATES, INC., a California corporation ("Landlord"), and DOCUMENTUM, INC., a
California corporation ("Tenant").

          Landlord hereby leases to Tenant and Tenant hereby leases from
Landlord that certain four-story office building ("Building") to be constructed
by Landlord at 6801 Koll Center Parkway with an area of approximately one
hundred twenty-two thousand four hundred forty-two (122,442) rentable square
feet as shown on EXHIBIT A-1 (the "Premises").  As an appurtenant right to
                 -----------                                              
Tenant's leasing of the Premises, Landlord hereby grants to Tenant, for the
benefit of Tenant and its employees, suppliers, shippers, customers and
invitees, during the term of this Lease, the non-exclusive right to use, in
common with others entitled to such use, (i) those portions of the common areas
within the Project and within Bernal Corporate Park which are improved from time
to time for use as parking areas, driveways, sidewalks, landscaped areas, or for
other common purposes including, for example the fitness center and conference
room currently available to the tenants of Bernal Corporate Park, and (ii) all
easements, licenses and similar rights and privileges relating to or appurtenant
to the Building or the Project and created or existing from time to time under
any written agreements.  For purposes of this Lease, all references herein to
the "Project" shall mean the Building plus the parcel of land upon which the
Building is constructed, including all parking facilities, driveways, sidewalks,
plazas, and landscaped areas appurtenant to the Building and within such parcel
of land, as more particularly shown on the site plan attached as EXHIBIT A-2.
                                                                 -----------  
Landlord and Tenant have also entered into a lease of even date herewith for
approximately sixty-three thousand six hundred thirty-two (63,632) rentable
square feet of space in the building to be constructed at 6701 Koll Center
Parkway, Pleasanton, California ("Sycamore Plaza II Lease").  The Premises shall
be measured in accordance with the Building Managers and Owners Association
Standard ANSI-Z65.1 (1996) to determine the rentable and usable area of the
Premises.  Tenant shall have the right to verify the measurement of the
Premises, at Tenant's expense, prior to the Commencement Date using the
foregoing BOMA standards.

          The parties hereto agree that said letting and hiring is upon and
subject to the terms, covenants and conditions herein set forth.  Landlord and
Tenant each covenant, as a material part of the consideration for this Lease to
keep and perform each and all of said terms, covenants and conditions for which
such party is liable hereunder and that this Lease is made upon the condition of
such performance.

          Prior to the commencing of the term of this Lease the Premises shall
be improved by the Tenant Improvements described in the Work Letter marked
EXHIBIT B attached hereto.  Tenant shall contribute the sum of Two Million Five
---------                                                                      
Hundred Thousand and no/100ths Dollars ($2,500,000.00) toward the cost of the
Tenant Improvements to the Premises ("Tenant's Contribution").  Tenant's
Contribution shall be due upon execution of this Lease and shall be non-
refundable to Tenant except as provided in paragraph 2(d).
<PAGE>
 
                                   ARTICLE 1
                                   ---------
                                     TERM
                                     ----

          (a) The term of this Lease shall be for seven (7) years unless sooner
terminated as hereinafter provided, commencing upon the date ("Commencement
Date") which is the earlier of:

               (i) Completion of the Base Building and substantial completion
(as defined in the Work Letter) of the Tenant Improvements to the Premises
described in the Work Letter (subject to the provisions of Paragraph 8 of the
Work Letter) and the tender of possession of the Premises to Tenant, subject
only to completion of "punch- list" items which do not in the aggregate
materially interfere with Tenant's ability to occupy the Premises for the use
contemplated herein, or

               (ii) The date that Tenant opened for business in the Premises,

and ending on the last day of the last month in the term of this Lease, unless
such term shall be sooner terminated as hereinafter provided.  As soon as the
Commencement Date is determined, the parties shall execute a written
acknowledgment setting forth the precise commencement and termination dates of
this Lease.  Failure to enter into such an amendment, however, shall not affect
Tenant's liability hereunder.  Reference in this Lease to a "Lease Year" shall
mean each successive twelve month period commencing with the Commencement Date.
Landlord and Tenant estimate that the Commencement Date shall be June 1, 1999.

          (b) Tenant shall be permitted to access the Premises approximately two
(2) weeks prior to the Commencement Date for the purpose of taking preparatory
measures in contemplation of its occupancy, including but not limited to,
installing fixtures and furniture, computer equipment, telecommunications
equipment, and other personal property, subject to all of the terms and
conditions of this Lease, except the obligation to pay Basic Rent or Direct
Expenses, provided that Tenant's access does not unreasonably interfere with
completion of the Tenant Improvements.

                                   ARTICLE 2
                                   ---------
                                  POSSESSION
                                  ----------

          (a) Landlord shall use diligent efforts to complete the Base Building
and the Tenant Improvements promptly.  Tenant agrees, however, that if Landlord
is unable to deliver possession of the Premises to Tenant on or before June 1,
1999, subject to the provisions of paragraphs 2(b) and 2(c), this Lease shall
not be void or voidable, nor shall Landlord be liable to Tenant for any loss or
damage resulting therefrom, but in such  event the term of this Lease shall not
commence until Landlord tenders possession of the Premises to Tenant with the
Tenant Improvements substantially completed.  If Landlord completes construction
of the Tenant Improvements and Base Building, including access thereto, prior to
the date scheduled in the Work Letter, Landlord shall deliver possession of the
Premises to Tenant upon such completion and the term of this Lease shall
commence five (5) days after Landlord has notified Tenant of such completion.
<PAGE>
 
          (b) If the Commencement Date has not occurred by July 1, 1999 for any
reason other than Tenant Delays (as defined in the Work Letter) or delays caused
by Force Majeure (as defined herein), then Tenant shall be entitled to one (1)
day of free Basic Rent for each day of delay in substantial completion that
occurs from and after July 1, 1999 (as such date may be extended by Tenant
Delays and Force Majeure delays) until the earlier of the Commencement Date or
December 1, 1999; provided, however, that no more than sixty (60) days of Force
Majeure delays may accrue at any time between the date this Lease is fully
executed and December 1, 1999 before Tenant is entitled to begin accruing free
Basic Rent.  If, however, the Commencement Date has not occurred by December 1,
1999, but Tenant has not elected to terminate this Lease as permitted in
paragraph 2(c) below, Tenant shall not be entitled to accrue any additional days
of free Basic Rent beyond December 1, 1999, regardless of when the Commencement
Date actually occurs.  If the completion of the Base Building and/or the Tenant
Improvements is delayed due to inclement weather, strikes or other labor
disturbances, material shortages, casualties, or other causes beyond Landlord's
reasonable control ("Force Majeure"), Landlord shall notify Tenant in writing
within two (2) business days after the occurrence thereof that an event of Force
Majeure has occurred and will delay the Commencement Date, and in such event the
date for substantial completion of the Base Building and the Tenant Improvements
shall be extended for the period of time reasonably attributable to the
occurrence of such Force Majeure.

          (c) If Landlord has not obtained a building permit for the Base
Building by October 15, 1998, then Tenant may cancel this Lease by delivery of
written notice to Landlord no later than October 31, 1998.  Furthermore, if the
Commencement Date has not occurred by December 1, 1999 for any reason other than
Tenant Delays, then Tenant may cancel this Lease by delivery of written notice
to Landlord no later than December 31, 1999.  Landlord shall have the right to
cancel this Lease if the Commencement Date has not occurred due to more than 365
days of delay caused by Force Majeure.  In such event, Landlord may cancel this
Lease by written notice to Tenant within thirty (30) days after the occurrence
of the 365th day of Force Majeure delays.  Upon cancellation of this Lease by
either party, Landlord shall return to Tenant all sums previously deposited with
Landlord by Tenant, Tenant shall return to Landlord the letter of credit
provided by Landlord under paragraph 2(d) below, and neither party shall have
any further liability to the other under this Lease.  If either party elects to
cancel this Lease as permitted herein, such cancellation and the return of all
sums previously paid by Tenant shall be in lieu of any free rent to which Tenant
may be entitled under paragraph 2(b), shall be Tenant's sole and exclusive
remedy for Landlord's inability to obtain a building permit for the Base
Building by October 15, 1998, or to complete the Base Building and the Tenant
Improvements by December 1, 1999, as the case may be, and Landlord shall have no
liability to Tenant for any other damages or losses suffered or incurred by
Tenant as a result thereof.

          (d) Landlord shall deliver to Tenant, upon execution of this Lease, an
irrevocable standby letter of credit in the amount of $2,500,000.00 issued by
NationsBank and naming Tenant as beneficiary thereunder, as security for the
return of Tenant's Contribution in the event this Lease is canceled by either
Landlord or Tenant pursuant to paragraph 2(c) above, or as a result of a
"Landlord Default" that occurs any time prior to the Commencement Date.  The
letter of credit shall be issued initially for a term of twelve (12) months and
shall be renewed automatically for consecutive periods of one (1) month until
the Commencement Date occurs.  Upon the occurrence of the Commencement Date, the
letter of credit shall be canceled and returned to 
<PAGE>
 
Landlord. Tenant shall have the right to draw upon the letter of credit for the
full amount thereof if: (i) Landlord fails to return Tenant's Contribution to
Tenant within thirty (30) days after a notice of cancellation is delivered by
Tenant or Landlord pursuant to paragraph 2(c); (ii) a Landlord Default occurs
prior to the Commencement Date; or (iii) at any time prior to the Commencement
Date, Tenant does not receive written notice from either Landlord or the issuing
bank, at least ten (10) days prior to the expiration of the letter of credit,
that the letter of credit is being renewed for another month. Tenant shall not,
however, be permitted to draw upon the letter of credit prior to December 1,
1999 except in the event of a Landlord Default that occurs prior to the
Commencement Date or a failure to renew the letter of credit that occurs prior
to December 1, 1998. Drawing upon the letter of credit shall be conditioned only
upon presentation of the original letter of credit to the issuer thereof
accompanied by either (i) a copy of Tenant's notice of cancellation to Landlord
or Landlord's notice of cancellation to Tenant, pursuant to paragraph 2(c), or
(ii) a certified statement by Tenant that a Landlord Default has occurred prior
to the Commencement Date. The letter of credit shall not be mortgaged, assigned
or encumbered in any manner whatsoever by Landlord. For purposes of this
paragraph 2(d), a "Landlord Default" shall mean only the following: a default by
Landlord under any mortgage or deed of trust recorded against the Project,
including any mortgage or deed of trust in favor of Landlord's construction
lender; the filing by or against Landlord of a petition to have Landlord
adjudged a bankrupt or a petition for reorganization or arrangement under any
law relating to bankruptcy (unless, in the case of a petition filed against
Landlord, the same is dismissed within sixty days); the appointment of a trustee
or receiver to take possession of substantially all of Landlord's assets or of
Landlord's interest in this Lease, where possession is not restored to Landlord
within thirty days; or the attachment, execution or other judicial seizure of
substantially all of Landlord's assets located or of Landlord's interest in this
Lease where such seizure is not discharged within thirty days. Landlord shall
notify Tenant in writing of any default by Landlord under any mortgage or deed
of trust recorded against the Project that occurs prior to the Commencement Date
and shall use reasonable efforts to secure a similar covenant from the holders
of any mortgage or deed of trust recorded against the Project prior to the
Commencement Date.

                                   ARTICLE 3
                                   ---------
                                  BASIC RENT
                                  ----------

          (a) Tenant agrees to pay Landlord Basic Rent for the Premises  as
follows:

                                Months of Term  Basic Rent/Per Month
                                --------------  --------------------

80,000 sq. ft.                   1 through 30    $133,600.00/month
                                31 through 60    $138,400.00/month
                                61 through 84    $149,600.00./month


42,442 sq. ft. (plus or minus)   1 through 60    $ 95,495.00/month
                                61 through 84    $ 99,739.00/month

The Basic Rent shall be paid monthly, in advance on the first (1st) day of each
calendar month during the term, commencing on the first (1st) month of the Lease
term and continuing on the first 
<PAGE>
 
day of each month thereafter, except that the first (1st) month's rent shall be
paid on execution hereof. If Tenant's obligation to pay rent commences or ends
on a day other than the first day of a calendar month, then the rental for such
period shall be prorated in the proportion that the number of days this Lease is
in effect during such period bears to thirty. In addition to the Basic Rent,
Tenant agrees to pay as additional rental the amount of rental adjustments and
other charges required by this Lease. All rental shall be paid to Landlord,
without prior demand and without any deduction or offset, except as otherwise
expressly provided herein, in lawful money of the United States of America, at
the address of Landlord designated on the signature page of this Lease or to
such other person or at such other place as Landlord may from time to time
designate in writing.

          (b) Late Charges.   In the event Tenant fails to pay any installment
              ------------                                                    
of rent when due or Tenant fails to make any other payment for which Tenant is
obligated under this Lease when due, and such failure continues for more than
three (3) business days after the date such rent or other payment is due, then
Tenant shall pay to Landlord a late charge equal to 5% of the amount due to
compensate Landlord for the extra costs incurred as a result of such late
payment; provided, however, that Landlord agrees to waive such late charge for
the first instance in any calendar year that any rent or other payment is not
paid within such three-day period.

                                   ARTICLE 4
                                   ---------
                               RENTAL ADJUSTMENT
                               -----------------

          (a) For the purpose of this Article 4, the following terms are defined
as follows:

               (i) Tenant's Percentage.   That portion of the Project occupied
                   -------------------    
by Tenant divided by the total rentable square footage of the Project, which
shall be one hundred percent (100%).

               (ii) Direct Expenses Base.  The amount of the annual Direct 
               --------------------                                           
Expenses which Landlord has included in Basic Rent, which amount is Tenant's
Percentage of the actual Direct Expenses for the Project for the third through
fourteenth months of the term.

               (iii)  Direct Expenses.   The term "Direct Expenses" shall
                      ---------------                                    
include:

                    (A)  All real and personal property taxes and assessments
(excluding those assessments described in Paragraph 4(a)(iii)(E)) imposed by any
governmental authority or agency on the Project and the land on which the
Project is located (including a pro-rata portion of any taxes levied on any
common areas); any assessments levied in lieu of taxes; any non-progressive tax
on or measured by gross rentals received from the rental of space in the
Project; and any other costs levied or assessed by, or at the direction of, any
federal, state, or local government authority in connection with the use or
occupancy of the Project or the parking facilities serving the Project; any tax
on this transaction or any document to which Tenant is a party creating or
transferring an interest in the Project, and any expenses, including the
reasonable cost of attorneys or experts, reasonably incurred by Landlord in
seeking reduction by the taxing authority of the above-referenced taxes, less
tax refunds obtained as a result of an application for review thereof; but shall
not include any net income, franchise, capital stock, estate or inheritance
taxes. Tenant's
<PAGE>
 
obligation to pay any assessments included within real property taxes and
assessments shall be calculated on the basis of the amount due if Landlord had
allowed the assessment to go to bond and the same were paid over the longest
period available. For the purposes of this Article 4, the real property taxes
and assessments included in the Direct Expenses Base shall be calculated as if
the Tenant Improvements were fully constructed and the Project, including the
Base Building and the Tenant Improvements, were fully assessed for real property
tax purposes.

                    (B) Operating costs consisting of costs incurred by Landlord
in maintaining and operating the Project, exclusive of costs required to be
capitalized for federal income tax purposes, and including (without limiting the
generality of the foregoing) the following: costs of utilities, supplies and
insurance, cost of services of independent contractors, managers and other
suppliers, cost of compensation (including employment taxes and fringe benefits)
of all persons who perform regular and recurring duties connected with the
management, operation, maintenance, and repair of the Project, its equipment,
parking facilities and the common areas, including, without limitation,
engineers, janitors (unless Tenant has elected to provide janitorial service to
the Premises as permitted in paragraph 16(b)), foremen, floor waxers, window
washers, watchmen and gardeners, cost of maintaining, repairing and replacing
landscaping, sprinkler systems, concrete walkways, paved parking areas, signs,
and site lighting.

                    (C) Amortization of such capital improvements as Landlord
may have installed for the purpose of reducing operating costs, but only to the
extent of the actual savings in operating costs realized as result of such
capital improvement(s). The cost of such capital improvements, together with
interest at the maximum rate allowed by law, shall be amortized over such
reasonable period as Landlord shall determine, and only the monthly amortized
cost shall be included in Direct Expenses monthly.
          
                    (D) Any costs required by the CC&R's, as defined in Article
6, affecting the Project or by any corporation, committee or association formed
in connection therewith,

                    (E) Assessments.  Tenant acknowledges that the Project is 
                        -----------   
subject to assessments levied to secure bonds sold by the City of Pleasanton
pursuant to Consolidated Reassessment District 1993-1. Such assessments shall be
Landlord's responsibility throughout the term of this Lease. Tenant hereby
consents to the formation of any other districts formed for maintenance,
utilities, landscaping, lighting, special service zones, fire district, water
district, road extensions, traffic mitigation, sports facilities or other
improvements in the Premises or Bernal Corporate Park and to the re-financing of
any assessment districts. Tenant hereby waives any right of notice and protest
in connection with the formation and continued existence of the assessment
districts; provided, however, that Tenant shall retain the right to contest the
amount of any new assessments levied against the Premises or the Project during
the term of this Lease. Tenant shall execute all documents, including, but not
limited to, petitions and formal waivers of notice and protest of formation,
evidencing such consent and waiver upon request of Landlord or the City of
Pleasanton.

               (iv) Exclusions from Direct Expenses.  Direct Expenses shall not
                    -------------------------------                            
include any of the following: (A) depreciation and other non-cash items; (B)
costs of tenants' 
<PAGE>
 
improvements; (C) capital items (except to the extent expressly permitted under
paragraph 4(a)(iii)(C)); (D) payments of principal and interest on debt; (E)
leasing commissions; (F) cost of any goods and services (including utilities)
for which any tenants or other occupants of the Project separately reimburse
Landlord; (G) costs incurred to perform or correct any tenant improvement work;
(H) costs of correcting defects in or inadequacy of the initial design of the
structure of the Building; (I) legal fees (except as expressly provided for in
paragraph 4(a)(iii)(A)); (J) amounts paid to affiliates of Landlord (i.e.,
persons or entities controlled by, under common control with, or which control,
Landlord) for services to the Project, to the extent that the costs of such
services exceed competitive costs for such services were they not rendered by an
affiliate of Landlord; (K) expenses in connection with services or other
benefits provided to one of more tenants but which are not generally available
to other tenants of the Project; (L) wages of any employee above the level of
Building manager and chief engineer; (M) space planning fees, architectural
fees, engineering fees (other than those relating to the general operation of
the Project), marketing, advertising or any expense incurred in connection with
the development or leasing of the Project; (N) costs associated with the
operation of the business of the legal entity which constitutes Landlord as the
same is separate from the costs of operation of the Project, including legal
entity formation and internal entity accounting; (O) any late fees or penalties
or similar fees incurred by Landlord, except to the extent attributable to
Tenant's late payment of Basic Rent, Direct Expenses or any other sums due under
this Lease; (P) any debt losses, rent losses or reserves for bad debt; (Q) any
expenses incurred for use of any public portions of the Project including, but
not limited to, shows and promotions; (R) the costs of installing an
observatory, broadcasting facility, luncheon club, athletic or recreational
club, and the costs of operating and maintaining any of the foregoing which are
in excess of the costs of services provided to other tenants of the Project
generally; (S) costs of adding any additional space to the Project after the
original construction; (T) costs of any repairs to the Project in accordance
with the provisions of Articles 21 (Damage and Destruction) and 22 (Eminent
Domain) of this Lease; (U) Landlord's incremental costs incurred by reasons of
Landlord's breach of any lease in the Project and any cost incurred by reason of
the breach by other tenants of the Project of such tenants' leases (to the
extent recoverable from such tenants); (V) unrecovered expenses incurred as a
consequence of the grossly negligent operation and maintenance of the Project by
Landlord or Landlord's employees; and (W) any fines, penalties, costs or
expenses incurred in connection with the investigation, removal, monitoring,
clean-up or other remediation of any contamination, or threatened contamination,
by Toxic Materials in, on or under the Premises or the Project.

          (b)  Payment of Direct Expenses.
               -------------------------- 

               (i) If Tenant's Percentage of the Direct Expenses paid or
incurred by Landlord for any calendar year of the term exceeds the Direct
Expenses Base, then Tenant shall pay such excess as additional rent. For each
calendar year, or portion thereof, after the first 12 full calendar months of
the term, Tenant shall pay Tenant's Percentage of Landlord's estimate of the
amount by which Direct Expenses for that year shall exceed the Direct Expenses
Base ("Landlord's Estimate"). This estimated amount shall be divided into twelve
equal monthly installments. Tenant shall pay to Landlord, concurrently with the
regular monthly rent payment next due following the receipt of such statement,
an amount equal to one monthly installment multiplied by the number of months
from January in the calendar year in which said statement is submitted to the
month of such payment, both months inclusive. Subsequent installments shall be
payable concurrently with the
<PAGE>
 
regular monthly rent payments for the balance of that calendar year and shall
continue until the next calendar year's statement is rendered.

               (ii) As soon as possible after the end of each calendar year,
Landlord shall provide Tenant with a statement showing the amount of Tenant's
Percentage of the actual Direct Expenses for such calendar year, the amount of
Landlord's Estimate actually paid by Tenant and the amount of the Direct
Expenses Base. Thereafter, Landlord shall reconcile the above amounts and shall
either bill Tenant for the balance due (payable on demand by Landlord) or credit
any overpayment by Tenant towards the next monthly installment of Landlord's
Estimate falling due, or refund such overpayment to Tenant at the expiration of
the Lease, as the case may be. For purposes of making these calculations, in no
event shall Tenant's Percentage of the Direct Expenses be deemed to be less than
the Direct Expenses Base.

               (iii) Within ninety (90) days after receipt of Landlord's
statement setting forth the actual Direct Expenses ("Landlord's Statement"),
Tenant shall have the right to audit at Landlord's local offices, at Tenant's
expense, Landlord's accounts and records relating to Direct Expenses. Such audit
shall be conducted by a certified public accountant approved by Landlord, which
approval shall not be unreasonably withheld. If such audit reveals that Landlord
has overcharged Tenant, the amount overcharged shall be paid to Tenant within
thirty (30) days after the audit is concluded, together with interest thereon at
the rate of ten percent (10%) per annum, from the date that payment of such
Direct Expenses was made by Tenant until reimbursement of the overcharge is made
to Tenant. In addition, if Landlord's Statement exceeds the actual Direct
Expenses which should have been charged to Tenant by more than five percent
(5%), the cost of the audit shall be paid by Landlord. Tenant and Tenant's
accountant shall keep any information gained by such audit confidential and
shall not disclose such information to any other party.

               (iv) If Landlord fails to do so within a reasonable time after
written request by Tenant, then Tenant, at its cost, shall have the right at any
time to seek a reduction in or otherwise contest any taxes or assessments for
which it is obligated to reimburse Landlord under this Article 4 and/or under
Article 10, by action or proceeding against the entity with authority to assess
or impose the same. Landlord further agrees, however, that if any action taken
by Landlord to seek a reduction in or otherwise contest any taxes or assessments
would prevent Tenant from taking any such action or otherwise prejudice Tenant's
right in such action if Landlord were unsuccessful in seeking a reduction in or
otherwise contesting such taxes or assessments, then Landlord and Tenant shall
cooperate in jointly contesting such taxes or assessments. Landlord shall not be
required to join in any proceeding or action brought separately by Tenant unless
the provisions of applicable laws or regulations or the like require that such
proceeding or action be brought by or in the name of Landlord, in which event
Landlord shall join in such proceeding or action or permit it to be brought in
Landlord's name, provided that Tenant protects, indemnifies, and holds Landlord
free and harmless from and against any liability, cost or expense in connection
with such proceeding or contest. Tenant shall continue, during the pendency of
such proceeding or action, to pay the taxes and assessments due as determined by
Landlord pursuant to this Article 4 and/or Article 10. If Tenant is successful
in such action or proceeding, Landlord shall reimburse to Tenant Tenant's share
of the reduction in taxes realized by Tenant in such contest or proceeding
within thirty (30) days after the amount of such reduction has been determined
and Landlord has received the applicable refund.
<PAGE>
 
          (c) Even though the term has expired and Tenant has vacated the
Premises, when the final determination is made of Tenant's Percentage of Direct
Expenses for the year in which this Lease terminates, Tenant shall immediately
pay any increase due over the estimated expenses paid and, conversely, any
overpayment made in the event said expenses decrease shall be promptly rebated
by Landlord to Tenant.

                                   ARTICLE 5
                                   ---------
                               SECURITY DEPOSIT
                               ----------------

          (a) Upon execution of this Lease, Tenant shall deposit with Landlord
an irrevocable standby letter of credit in the amount of One Million Seven
Hundred Thousand and no/100ths Dollars ($1,700,000.00) issued by Union Bank of
California (or another bank reasonably acceptable to Landlord), and naming
Landlord as beneficiary thereunder, as security for the faithful performance by
Tenant of all of Tenant's obligations under this Lease and the Sycamore Plaza II
Lease.  The letter of credit shall be in the form attached as EXHIBIT F to this
                                                              ---------        
Lease.  If Tenant fails to pay when due any rent or other sum due under this
Lease and such failure continues after notice from Landlord and the expiration
of any applicable grace period, regardless of whether Tenant has filed a
petition in bankruptcy under the federal bankruptcy laws, or if Tenant,
following the filing of any such petition, rejects this Lease or the Sycamore
Plaza II Lease, then Landlord may (but shall not be required to) draw upon the
letter of credit and use, apply or retain all or any part of the security
deposit for the payment of any rent or other sum then due and unpaid, or for the
payment of any other amount which Landlord may spend or become obligated to
spend by reason of Tenant's breach or to compensate Landlord for any other loss
or damage which Landlord may suffer by reason of Tenant's breach.  If any
portion of the letter of credit is drawn upon by Landlord for such purposes,
Tenant shall, within ten (10) days after written demand by Landlord, deposit a
replacement letter of credit with Landlord in the amount of the original letter
of credit.  Tenant's failure to do so shall be a material breach of this Lease.
The letter of credit, or so much thereof as remains after the curing of any
default of Tenant hereunder, shall be returned to Tenant at the expiration of
the Lease term and surrender of the Premises by Tenant.

          (b) The letter of credit shall be issued for a term of at least twelve
(12) months and shall be renewed automatically for consecutive twelve (12) month
periods for the entire term of this Lease subject, however, to reduction as
provided in paragraph 5(c) or 5(d).  If at any time during the term of this
Lease Landlord does not receive written notice from Tenant, at least ten (10)
days prior to the expiration of any twelve (12) month term of the letter of
credit, that the letter of credit is being renewed for another twelve (12)
months, then Landlord shall have the right to draw upon the letter of credit for
the full amount thereof. Drawing upon the letter of credit shall be conditioned
only upon presentation of the original letter of credit to the issuer thereof
accompanied by a certified statement from Landlord that Tenant is in default
under the Lease which default is continuing after notice and the expiration of
any applicable grace period.  The letter of credit shall not be mortgaged,
assigned or encumbered in any manner whatsoever by Tenant.  The use, application
or retention of the letter of credit, or any portion thereof, by Landlord shall
not prevent Landlord from exercising any other right or remedy provided by this
Lease or by law, it being intended that Landlord shall not first be required to
proceed against the letter of credit, and such use, application or retention
shall not operate as a limitation on any recovery to which Landlord may
otherwise be entitled.
<PAGE>
 
          (c) Provided that Tenant is not then in default under this Lease, the
security deposit shall be reduced to One Million Two Hundred Thousand and
no/100ths Dollars ($1,200,000.00) as of April 1, 2001, and Eight Hundred
Thousand and no/100ths Dollars ($800,000.00) as of April 1, 2002.  Provided that
Tenant is not then in default under this Lease, as of April 1, 2003, and for the
balance of the term, the security deposit retained by Landlord for this Lease
shall be equal to one monthly installment of the Basic Rent then payable under
this Lease.

          (d) If at any time during the term of this Lease the cross-default
provision set forth in paragraph 23(a)(v) of this Lease is terminated as
provided in paragraph 24(f) or paragraph 35, Tenant shall replace the letter of
credit then held by Landlord with two (2) separate letters of credit to be held
by Landlord or, if applicable, Landlord's successor or successors-in-interest,
as security for the performance of Tenant's obligations under this Lease and the
Sycamore Plaza II Lease, respectively.  The amount of the replacement letter of
credit to be delivered by Tenant as security for this Lease shall be determined
by multiplying the amount of the letter of credit then held by Landlord by a
fraction, the numerator of which shall be the rentable area of the Premises and
the denominator of which shall be the total rentable area of the Premises plus
the premises occupied by Tenant under the Sycamore Plaza II Lease.  Tenant's
failure to provide Landlord with the replacement letters of credit at least ten
(10) days prior to the effective date of an approved assignment, or within ten
(10) days after written notice from Landlord of a pending transfer or conveyance
of title to the Project, as applicable, shall constitute a default under this
Lease.

                                   ARTICLE 6
                                   ---------
                                      USE
                                      ---

          (a) Tenant shall use the Premises for general office, administrative,
sales demonstrations, training classes, and software development, and shall not
use or permit the Premises to be used for any other purpose without the prior
written consent of Landlord, which consent shall not be unreasonably withheld.
Nothing contained herein shall be deemed to give Tenant any exclusive right to
such use in the Project.  Tenant shall not use or occupy the Premises in
violation of law or of the certificate of occupancy issued for the Building or
Project, and shall, upon written notice from Landlord, discontinue any use of
the Premises which is declared by any governmental authority having jurisdiction
to be a violation of law or of said certificate of occupancy.  Tenant shall
comply with any direction of any governmental authority having jurisdiction
which shall, by reason of the nature of Tenant's use or occupancy of the
Premises, impose any duty upon Tenant or Landlord with respect to the Premises
or with respect to the use or occupation thereof.  Tenant's shall not do or
permit to be done anything which will invalidate or increase the cost of any
fire, extended coverage or any other insurance policy covering the Building
and/or Project and/or property located therein and shall comply with all rules,
orders, regulations and requirements of the Insurance Service Offices, formerly
known as the Pacific Fire Rating Bureau or any other organization performing a
similar function.  Tenant shall promptly, upon demand, reimburse Landlord for
any additional premium charged for such policy by reason of Tenant's failure to
comply with the provisions of this Article.  Tenant shall not do or permit
anything to be done in or about the Premises which will in any way unreasonably
obstruct or unreasonably interfere with the rights of other tenants or occupants
of the Project or Bernal Corporate Park, or injure or annoy them, or use or
allow the Premises to be used for any improper, immoral, unlawful or
objectionable purpose, nor shall Tenant cause, maintain 
<PAGE>
 
or permit any nuisance in, on or about the Premises. Tenant shall not commit or
suffer to be committed any waste in or upon the Premises.

          (b) Tenant acknowledges that Landlord has recorded covenants,
conditions and restrictions against the Premises on February 18, 1987 as
Instrument Number 87/046032 in the Official Records of Alameda County (the
"CC&Rs"), a true and correct copy of which has been previously delivered to
Tenant.  Tenant's use of the Premises shall be subject to and Tenant shall
comply with the CC&R's, as the same may be amended from time to time, provided,
however, that any amendment or modification thereof shall not materially
adversely affect Tenant's use and enjoyment of the Premises or access thereto.
Tenant acknowledges that there have been and may be from time to time recorded
easements and/or declarations granting or declaring easements for parking,
utilities, fire or emergency access, and other matters.  Tenant's use of the
Premises shall be subject to and Tenant shall comply with any and all such
easements and declarations.  Tenant's use of the Premises shall be subject to
such guidelines as may from time to time be prepared by Landlord or the Bernal
Corporate Park Owner's Association in their reasonable discretion.

          (c) Tenant acknowledges that governmental entities with jurisdiction
over the Premises may, from time to time promulgate laws, rules, plans and
regulations affecting the use of the Premises, including, but not limited to,
traffic management plans and energy conservation plans.  Tenant's use of the
Premises shall be subject to and Tenant shall comply with any and all such laws,
rules, plans, and regulations.  Notwithstanding the foregoing or anything to the
contrary contained in this Lease, Tenant shall not be responsible for compliance
with any laws, codes, ordinances, rules, regulations or other governmental
directives, including without limitation, the Americans with Disabilities Act
(collectively, "Applicable Laws") which require any alterations or improvements
to any portions of the Project other than the Premises, unless such compliance
is required solely as a result of any other alterations or improvements made to
the Premises by Tenant.  Furthermore, if any capital improvements are required
to the Premises to comply with any Applicable Laws (other than capital
improvements which are required solely as a result of any other alterations or
improvements made to the Premises by Tenant, which shall be made at Tenant's
sole expense), such improvements shall be made by Landlord and the cost of such
capital improvements, together with interest at the maximum rate allowed by law,
shall be amortized over such reasonable period as Landlord shall determine, and
Tenant shall reimburse Landlord, monthly, as additional rent, the monthly
amortized cost of such improvement that is allocable to the then remaining term
of this Lease.  Notwithstanding anything herein to the contrary, Landlord shall
be solely responsible for the cost of any alterations or improvements, including
capital improvements, to the structural portions of the Building, the Building
elevators, the restrooms, and the base Building electrical, mechanical, plumbing
and HVAC systems installed by Landlord prior to the Commencement Date, and the
common areas of the Project, which are required to comply with any Applicable
Laws.

          (d) Tenant, at its sole cost, shall comply with all laws relating to
Tenant's storage, use and disposal of hazardous, toxic or radioactive matter,
including those materials identified in Sections 66680 through 66685 of Title 33
of the California Code of Regulations as they may be amended from time to time
(collectively "Toxic Materials").  If Tenant does store, use or dispose of any
Toxic Materials, other than normal amounts of cleaning supplies and office
products, Tenant shall notify Landlord in writing at least ten (10) days prior
to their first appearance on the Premises.  Landlord represents and warrants to
Tenant that, to the best of Landlord's actual 
<PAGE>
 
knowledge without independent investigation or inquiry, as of the date of this
Lease (i) there are no underground storage tanks located on the Project, (ii)
there has been no release onto or under the Project of any Toxic Materials in
violation of applicable environmental laws, and (iii) Landlord has received no
notices of any pending litigation, clean-up orders or other governmental action
with respect to the environmental condition of the Project. For the purposes of
this paragraph 6(d), the "actual knowledge of Landlord" shall be limited to the
actual knowledge of Loryssa Rippey and Timothy Wirta.

                                   ARTICLE 7
                                   ---------
                                    NOTICES
                                    -------

          Any notice required or permitted to be given hereunder must be in
writing and may be given by personal delivery or by mail, and if given by mail
shall be deemed sufficiently given if sent by registered or certified mail
addressed to Tenant at the Project, or to Landlord at its address set forth at
the end of this Lease.  Either party may specify a different address for notice
purposes by written notice to the other except that the Landlord may in any
event use the Premises as Tenant's address for notice purposes.

                                   ARTICLE 8
                                   ---------
                                    BROKERS
                                    -------

          Tenant and Landlord warrants that it has had no dealings with any real
estate broker or agent in connection with the negotiation of this Lease, except
Parkway Properties, Inc. and Colliers Parrish International whose commission
shall be payable by Landlord, and that it knows of no other real estate broker
or agent who is or might be entitled to a commission in connection with the
Lease.  If Tenant or Landlord, as the case may be, has dealt with any other
person or real estate broker with respect to leasing or renting space in the
Project, Tenant or Landlord, as the case may be, shall be solely responsible for
the payment of any fee due said person or firm and Tenant or Landlord, as the
case may be, shall hold the other party free and harmless against any liability
in respect thereto, including attorneys' fees and costs.

                                   ARTICLE 9
                                   ---------
                                 HOLDING OVER
                                 ------------

          If Tenant holds over after the expiration or earlier termination of
the term hereof without the express written consent of Landlord, Tenant shall
become a Tenant at sufferance only, at a rental rate equal to one hundred
twenty-five percent (125%) of the rent in effect upon the date of such
expiration for the first sixty (60) days of any such holdover, and one hundred
fifty percent (150%) of the rent in effect upon the date of such expiration for
any holdover continuing after such 60-day period (subject to adjustment as
provided in Paragraph 4 hereof and prorated on a daily basis), and otherwise
subject to the terms, covenants and conditions herein specified, so far as
applicable.  Acceptance by Landlord of rent after such expiration or earlier
termination shall not result in a renewal of this Lease.  The foregoing
provisions of this Article 9 are in addition to and do not affect Landlord's
right of re-entry or any rights of Landlord hereunder or as otherwise provided
by law.  If Tenant fails to surrender the Premises upon the expiration of this
Lease despite demand to do so by Landlord, Tenant shall indemnify and hold
Landlord harmless from all loss or 
<PAGE>
 
liability, including without limitation, any claim made by any succeeding tenant
founded on or resulting from such failure to surrender and any attorneys' fees
and costs.

                                  ARTICLE 10
                                  ----------
                          TAXES ON TENANT'S PROPERTY
                          --------------------------

          (a) Tenant shall be liable for and shall pay, at least ten days before
delinquency, all taxes levied against any personal property or trade fixtures
placed by Tenant in or about the Premises.  If any such taxes on Tenant's
personal property or trade fixtures are levied against Landlord or Landlord's
property of if the assessed value of the Premises is increased by the inclusion
therein of a value placed upon such personal property or trade fixtures of
Tenant and if Landlord, after written notice to Tenant, pays the taxes based
upon such increased assessment, which Landlord shall have the right to do
regardless of the validity thereof, but only under proper protest if requested
by Tenant, Tenant shall, upon demand, repay to Landlord the taxes so levied
against Landlord, or the portion of such taxes resulting from such increase in
the assessment.

          (b) If the Tenant Improvements in the Premises, whether installed,
and/or paid for by Landlord or Tenant and whether or not affixed to the real
property so as to become a part thereof, are assessed for real property tax
purposes at a valuation higher than the valuation at which Tenant Improvements
conforming to Landlord's "Project Standard" in other space in the Project are
assessed (which for purposes of this paragraph shall mean tenant improvement
costs in excess of $30.00 per rentable square foot for hard construction costs
only [i.e., exclusive of architectural and engineering fees, permit fees, and
construction management fees]), then the real property taxes and assessment
levied against the Project by reason of such excess assessed valuation shall be
deemed to be taxes levied against personal property of Tenant and shall be
governed by the provisions of Paragraph 10(a), above.   If the records of the
County Assessor are available and sufficiently detailed to serve as a basis for
determining whether said Tenant Improvements are assessed at a higher valuation
than Landlord's Project Standard, such records shall be binding on both the
Landlord and the Tenant.  If the records of the County Assessor are not
available or sufficiently detailed to serve as a basis for making said
determination, the actual cost of construction shall be used.

                                  ARTICLE 11
                                  ----------
                             CONDITION OF PREMISES
                             ---------------------
<PAGE>
 
          (a) Landlord represents and warrants, that as of the Commencement
Date, to the best of its knowledge, the Premises and the Building shall be
constructed  in compliance with all Applicable Laws.  Landlord further warrants
to Tenant that the Base Building and Tenant Improvements constructed by Landlord
shall be (i) free from material structural defects and shall not violate the
CC&R's or any other covenants or restrictions of record, and (ii) constructed in
compliance in all material respects with the Base Building Plans and the Tenant
Improvement Plans approved by Landlord and Tenant subject to any changes
implemented in such plans in accordance with the procedures set forth in the
Work Letter.  Subject to the foregoing, Tenant acknowledges that neither
Landlord nor any agent of Landlord has made any representation or warranty with
respect to the Premises or the Project or with respect to the suitability of
either for the conduct of Tenant's business.  Subject to Landlord's
representations and warranties and Landlord's obligation to complete any punch-
list items as provided in paragraph 9 of the Work Letter, and excluding any
latent defects, the taking of possession of the Premises by Tenant shall
conclusively establish that the Premises were in satisfactory condition at such
time.

          (b) If it is determined that any of the warranties in paragraph 11(a)
have been violated in any respect, then it shall be the obligation of Landlord,
after receipt of written notice from Tenant setting forth with specificity the
nature of the violation, to promptly correct the condition(s) constituting such
violation at Landlord's sole cost.  Landlord shall assign to Tenant Landlord's
rights under all contractors' and manufacturers' warranties relating to the
Tenant Improvements (provided, however, that Landlord may reserve joint
enforcement rights under such warranties to the extent of Landlord's continuing
obligations or warranties hereunder), and shall cooperate with Tenant in all
reasonable respects in any enforcement of such warranties.

                                  ARTICLE 12
                                  ----------
                                  ALTERATIONS
                                  -----------

          (a) Tenant shall make no alterations, additions or improvements in or
to the Premises without Landlord's prior written consent, which shall not be
unreasonably withheld; provided, however, that Landlord's consent shall not be
required for any alterations, additions or improvements to the Premises that (i)
do not cost more than $15,000 per work of improvement nor more than $50,000
cumulatively per annum, and (ii) do not affect any structural or exterior
portion of the Building or the Building's electrical, plumbing or HVAC systems,
except that Landlord's consent shall, in any event, be required for any
demolition of any alterations, additions or improvements to the Premises.   All
work shall be performed by contractors or mechanics approved by Landlord and
shall be done in a good and workmanlike manner.  Tenant covenants and agrees
that all work done by Tenant shall be performed in full compliance with all
Applicable Laws and in full compliance with the rules, regulations and
requirements of the Insurance Service Offices formerly known as the Pacific Fire
Rating Bureau, and of any similar body.  Before commencing any work, Tenant
shall give Landlord at least ten days written notice of the proposed
commencement of such work and shall, if the cost of such alterations exceeds
$50,000 and if so requested by Landlord, secure at Tenant's own cost and
expense, a completion and lien indemnity bond, reasonably satisfactory to
Landlord, for said work.  Tenant further covenants and agrees that any
mechanic's lien filed against the Premises or against the Building or Project
for work claimed to have been done for, or materials claimed to have been
furnished to, Tenant will be discharged by Tenant, by bond or otherwise, within
ten days after the filing thereof, at the cost and expense of Tenant.  All
<PAGE>
 
alterations, additions or improvements upon the Premises made by either party,
including (without limiting the generality of the foregoing) all wallcovering,
built-in cabinet work, paneling and the like, shall become the property of
Landlord, and shall remain upon, and be surrendered with the Premises, as a part
thereof, at the end of the term hereof, except that Landlord may, by written
notice to Tenant given to Tenant at the time that Landlord grants its consent to
any alterations, additions or improvements, require Tenant to remove such
alterations, additions and improvements at the expiration or sooner termination
of this Lease, and in such event Tenant shall repair all damage resulting from
such removal or, at Landlord's option, shall pay to Landlord all costs arising
from such removal. Landlord and Tenant agree, however, that the Tenant
Improvements shall become the property of Landlord upon installation, shall
remain upon and be surrendered with the Premises at the expiration or sooner
termination of this Lease, and Tenant shall have no obligation to remove the
Tenant Improvements from the Premises.

          (b) All articles of personal property and all business and trade
fixtures, machinery and equipment, furniture and movable partitions owned by
Tenant or installed by Tenant at its expense in the Premises shall be and remain
the property of Tenant and may be removed by Tenant at any time during the lease
term when Tenant is not in default hereunder.  If Tenant shall fail to remove
all of its effects from the Premises upon termination of this Lease for any
cause whatsoever, Landlord may, at its option, remove the same in accordance
with applicable law, and store said effects without liability to Tenant for loss
thereof.  In such event, Tenant agrees to pay Landlord upon demand any and all
expenses incurred in such removal, including court costs and attorneys' fees and
storage charges on such effects for any length of time that the same shall be in
Landlord's possession.  Landlord may, at its option, without notice, sell said
effects, or any of the same, at private sale and without legal process, for such
price as Landlord may obtain and apply the proceeds of such sale upon any
amounts due under this Lease from Tenant to Landlord and upon the expense
incident to the removal and sale of said effects.

                                  ARTICLE 13
                                  ----------
                                    REPAIRS
                                    -------

          (a) Subject to Landlord's representations and warranties contained
herein and the punch list items, by entry hereunder, Tenant accepts the Premises
as being in good and sanitary order, condition and repair, excluding any latent
defects.  Tenant shall keep, maintain and preserve the Premises in good
condition and repair.  Tenant shall, upon the expiration or sooner termination
of the term hereof, surrender the Premises to Landlord in the same condition as
when received, usual and ordinary wear and tear and damage due to casualty or
condemnation excepted.  Except as expressly provided in EXHIBIT B attached
                                                        ---------         
hereto, Landlord shall have no obligation to alter, remodel, improve, decorate
or paint the Premises or any part thereof.  The parties hereto affirm that
Landlord has made no representations to Tenant respecting the condition of the
Premises or the Project except as specifically herein set forth.

          (b) Anything contained in Paragraph 13(a) above to the contrary
notwithstanding, Landlord shall repair and maintain the structural portions of
the Building, including the foundations, building shell, and roof structure, all
at Landlord's expense.  Landlord shall also repair and maintain the common areas
and the basic plumbing, elevators, life safety systems and other building
systems, including heating, ventilating, air conditioning and electrical systems
<PAGE>
 
installed or furnished by Landlord, and perform roof membrane repair and
maintenance to the Premises; the cost of such repairs and maintenance shall be
included in Direct Expenses as provided in Article 4, except to the extent such
repair, maintenance or replacement is required by the gross negligence or
willful misconduct of Landlord, its agents or employees or a breach by Landlord
of its obligations under this Lease.  Landlord shall not be liable for any
failure to make any such repairs or to perform any maintenance unless such
failure shall persist for an unreasonable time after written notice of the need
of such repairs or maintenance is given to Landlord by Tenant.  Except as
provided in Article 21 hereof, there shall be no abatement of rent and no
liability of Landlord by reason of any injury to or interference with Tenant's
business arising from the making of any repairs, alterations or improvements in
or to any portion of the Building, Project or the Premises or in or to fixtures,
appurtenances and equipment therein.  Tenant waives the right to make repairs at
Landlord's expense under any law, statute or ordinance now or hereafter in
effect.

                                  ARTICLE 14
                                  ----------
                                     LIENS
                                     -----

          Tenant shall not permit any mechanic's, materialmen's or other liens
to be filed against the Building or Project, nor against Tenant's leasehold
interest in the Premises.  Landlord shall have the right at all reasonable times
to post and keep posted on the Premises any notices which it deems necessary for
protection from such liens.  If any such liens are filed, Landlord may, without
waiving its rights and remedies based on such breach of Tenant and without
releasing Tenant from any of its obligations, cause such liens to be released by
any means it shall deem proper, including payments in satisfaction of the claim
giving rise to such lien.  Tenant shall pay to Landlord, within ten (10) days
after invoice, any sum paid by Landlord to remove such liens, together with
interest at the maximum rate per annum permitted by law from the date of such
payment by Landlord.

                                  ARTICLE 15
                                  ----------
                               ENTRY BY LANDLORD
                               -----------------

          Landlord reserves and shall with reasonable notice (except in the case
of emergencies and regularly scheduled janitorial services) have the right to
enter the Premises to inspect the same, to supply janitorial service and any
service to be provided by Landlord to Tenant hereunder, to show the Premises to
prospective purchasers or tenants (but as to tenants only during the last nine
(9) months of the term), to post notices of nonresponsibility, to alter, improve
or repair the Premises or any other portion of the Building or Project, all
without being deemed guilty of any eviction of Tenant and without abatement of
rent.  Landlord may, in order to carry out such purposes, erect scaffolding and
other necessary structures where reasonably required by the character of the
work to be performed, provided that the business of Tenant shall be interfered
with as little as is reasonably practicable.   Tenant hereby waives any claim
for damages for any injury or inconvenience to or interference with Tenant's
business, any loss of occupancy or quiet enjoyment of the Premises, and any
other loss in, upon and about the Premises.  Landlord shall at all times have
and retain a key with which to unlock all doors in the Premises, excluding
Tenant's vaults and safes.  Landlord shall have the right to use any and all
means which Landlord may deem proper to open said doors in an emergency in order
to obtain entry to the Premises provided Landlord shall promptly repair any
damage to the Premises caused by such entry.  Any entry to the Premises obtained
by Landlord by any of said means, or otherwise, shall not be construed or deemed
to be a forcible or 
<PAGE>
 
unlawful entry into the Premises, or any eviction of Tenant from the Premises or
any portion thereof, and any damages caused to the Premises on account thereof
shall be paid by Landlord. It is understood and agreed that no provision of this
Lease shall be construed as obligating Landlord to perform any repairs,
alterations or decorations except as otherwise expressly agreed herein by
Landlord.

                                  ARTICLE 16
                                  ----------
                            UTILITIES AND SERVICES
                            ----------------------

          (a) Landlord agrees to furnish or cause to be furnished to the
Premises the utilities and services described in the Standards for Utilities and
Services, attached hereto as EXHIBIT C, subject to the conditions and in
                             ---------                                  
accordance with the standards set forth therein.  Landlord's failure to furnish
any of the foregoing items when such failure is caused by:

                    (i) Accident, breakage, or repairs,

                    (ii) Strikes, lockouts or other labor disturbance or labor
dispute of any character,

                    (iii)  Governmental regulation, moratorium or other
governmental action,

                    (iv) Inability despite the exercise of reasonable diligence
to obtain electricity, water or fuel, or by

                    (v) Any other cause beyond Landlord's reasonable control,
shall not result in any liability to Landlord.

In addition, Tenant shall not be entitled to any abatement or reduction of rent
by reason of such failure, no eviction of Tenant shall result from such failure
and Tenant shall not be relieved from the performance of any covenant or
agreement in this Lease because of such failure; provided, however, that if any
such failure shall continue for more than three (3) consecutive business days
and as result of such failure Tenant's use of or access to the Premises is
materially impaired, then Tenant shall be entitled to a proportionate abatement
of rent for the period and to the extent of such impairment if, and only if, the
failure was caused by the negligence or willful misconduct of Landlord, its
agents or employees or by a breach of this Lease by Landlord, or such abatement
of rent will be covered by Landlord's rent loss insurance.  In the event of any
failure, stoppage or interruption thereof, Landlord shall diligently attempt to
resume service promptly.

          (b) Tenant shall have the right, at Tenant's election, to provide
janitorial service to the Premises at Tenant's sole cost and expense through a
contractor approved by Landlord, which approval shall not be unreasonably
withheld, and in such event the cost of providing janitorial service to the
Premises shall be excluded from Direct Expenses.

          (c) Subject to Tenant's receipt of all necessary approvals from the
City of Pleasanton and under the CC&R's, Tenant shall have the right to install
and operate, at Tenant's 
<PAGE>
 
sole cost and expense, an emergency power generator on the Project at a location
mutually acceptable to Landlord and Tenant. The use and operation of such
generator, including periodic testing, shall be subject to such reasonable rules
as Landlord may establish prior to installation of the generator.

                                  ARTICLE 17
                                  ----------
                                  BANKRUPTCY
                                  ----------

          If Tenant shall file a petition in bankruptcy under any provision of
the Bankruptcy Code as then in effect, or if Tenant shall be adjudicated a
bankrupt in involuntary bankruptcy proceedings and such adjudication shall not
have been vacated within sixty days from the date thereof, or if a receiver or
trustee shall be appointed of Tenant's property and the order appointing such
receiver or trustee shall not be set aside or vacated within sixty days after
the entry thereof, or if Tenant shall assign Tenant's estate or effects for the
benefit of creditors, or if this Lease shall, by operation of law or otherwise,
pass to any person or persons other than Tenant, then in any such event Landlord
may terminate this Lease, if Landlord so elects, with or without notice of such
election and with entry or action by Landlord.  In such case, notwithstanding
any other provisions of this Lease, Landlord, in addition to any and all rights
and remedies allowed by law or equity, shall, upon such termination, be entitled
to recover damages in the amount provided in Paragraph 23(b) hereof.  Neither
Tenant nor any person claiming through or under Tenant or by virtue of any
statute or order of any court shall be entitled to possession of the Premises
but shall surrender the Premises to landlord.  Nothing contained herein shall
limit or prejudice the right of Landlord to recover damages by reason of any
such termination equal to the maximum allowed by any statute or rule of law in
effect at the time when, and governing the proceedings in which, such damages
are to be proved; whether or not such amount is greater, equal to, or less than
the amount of damages recoverable under the provisions of this Article 17.
<PAGE>
 
                                  ARTICLE 18
                                  ----------
                                INDEMNIFICATION
                                ---------------

          Tenant shall indemnify, defend and hold Landlord harmless from all
claims arising from Tenant's use of the Premises or the conduct of its business
or from any activity, work, or thing done, permitted or suffered by Tenant in or
about the Premises except to the extent arising from the  negligence or willful
misconduct of Landlord, its agents, or employees or from a breach by Landlord of
its obligations under this Lease.  Tenant shall further indemnify, defend and
hold Landlord harmless from all claims arising from any breach or default in the
performance of any obligation to be performed by Tenant under the terms of this
Lease, or arising from the negligence or willful misconduct of Tenant or of its
agents or employees, and from and against all costs, attorneys' fees, expenses
and liabilities incurred in or about such claim or any action or proceeding
brought thereon.  In case any action or proceeding shall be brought against
Landlord by reason  of any such claim, Tenant upon notice from Landlord shall
defend the same at Tenant's expense by counsel approved in writing by Landlord.
Tenant, as a material part of the consideration to Landlord, hereby assumes all
risk of damage to property or injury to person in, upon or about the Premises
from any cause whatsoever except that which is caused by the failure of Landlord
to observe any of the terms and conditions of this Lease where such failure has
persisted for an unreasonable period of time after written notice of such
failure.  Tenant hereby waives all its claims in respect thereof against
Landlord.

                                  ARTICLE 19
                                  ----------
                          DAMAGE TO TENANT'S PROPERTY
                          ---------------------------

          Notwithstanding the provisions of Article 18 to the contrary, Landlord
or its agents shall not be liable for (i) any damage to any property entrusted
to employees of the Project, (ii) loss or damage to any property by theft or
otherwise, (iii) any damage to property resulting from fire, explosion, falling
plaster, steam, gas, electricity, water or rain which may leak from any part of
the Project or from the pipes, appliances or plumbing work therein or from the
roof, street or sub-surface or from any other place or resulting from dampness
or from any other cause whatsoever except to the extent any such loss or damage
is caused by the negligence or willful misconduct of Landlord,  its agents or
employees or a breach by Landlord of its obligations under this Lease and such
loss or damage is not covered by under any insurance Tenant is required to carry
pursuant to paragraph 20(a) or any other insurance Tenant elects to carry.
Landlord or its agents shall not be liable for interference with light or other
incorporeal hereditaments.  Tenant shall give prompt notice to Landlord in case
of fire or accidents in the Premises or in the Project or of defects therein or
in the fixtures or equipment of which Tenant has actual knowledge.

                                  ARTICLE 20
                                  ----------
                                   INSURANCE
                                   ---------

          (a)  Tenant shall, during the term hereof and any other period of
occupancy, at its sole cost and expense, keep in full force and effect the
following insurance:

               (i) Standard form property insurance insuring against the perils
of fire, extended coverage, vandalism, malicious mischief, special extended
coverage ("All-Risk") and
<PAGE>
 
sprinkler leakage. This insurance policy shall be upon all property owned by
Tenant, for which Tenant is legally liable or that was installed at Tenant's
expense, and which is located in the Project including, without limitation,
furniture, fittings, installations, fixtures (other than Tenant Improvements
installed by Landlord), and any other personal property in an amount not less
than ninety percent of the full replacement cost thereof. In the event that
there shall be a dispute as to the amount which comprises full replacement cost,
the decision of Landlord or any mortgagees of Landlord shall be conclusive. This
insurance policy shall also be upon direct or indirect loss of Tenant's earnings
attributable to Tenant's inability to use fully or obtain access to the Premises
or Project in an amount as will properly reimburse Tenant.

               (ii) Commercial General Liability Insurance insuring Tenant
against any liability arising out of the lease, use, occupancy or maintenance of
the Premises and all areas appurtenant thereto. Such insurance shall be in the
amount of $5,000,000 Combined Single Limit for injury to, or death of one or
more persons in an occurrence, and for damage to tangible property (including
loss of use) in an occurrence, with such liability amount to be adjusted from
year to year to reflect increases in the Consumer Price Index. The policy shall
insure the hazards of premises and operation, contractual liability (covering
the Indemnity contained in Paragraph 18 hereof) and shall (1) name Landlord as
an additional insured, and (2) contain a cross liability provision, and (3)
contain a provision that "the insurance provided the Landlord hereunder shall be
primary and non-contributing with any other insurance available to the
Landlord."

               (iii) Workers' Compensation and Employer's Liability insurance
(as required by state law).

               (iv) Any other form or forms of insurance as Tenant or Landlord
or any mortgagees of Landlord may reasonably require from time to time in form,
in amounts and for insurance risks against which a prudent tenant would protect
itself.

          (b) All policies shall be written in a form satisfactory to Landlord
and shall be taken out with insurance companies holding a General Policyholders
Rating of "A" and a Financial Rating of "X" or better, as set forth in the most
current issue of Bests Insurance Guide.  Within ten days after the execution of
this Lease, Tenant shall deliver to Landlord copies of policies or certificates
evidencing the existence of the amounts and forms of coverage satisfactory to
Landlord.  No such policy shall be cancelable or reducible in coverage except
after thirty days prior written notice to Landlord.  Tenant shall, within ten
days prior to the expiration of such policies, furnish Landlord with renewals or
"binders" thereof, or Landlord may order such insurance and charge the cost
thereof to Tenant as additional rent.  If Landlord obtains any insurance that is
the responsibility of Tenant under this section, Landlord shall deliver to
Tenant a written statement setting forth the cost of any such insurance and
showing in reasonable detail the manner in which it has been computed.

          (c) Landlord shall, during the term hereof, keep in full force and
effect the following insurance, which Landlord shall obtain at competitive
rates:

               (i) Commercial general liability insurance against claims for
personal injury, death or property damage arising out of the use, occupancy, or
maintenance of the 
<PAGE>
 
Project (other than the Premises), in a combined single limit amount of not less
than $5,000,000 per occurrence, and $5,000,000 in the aggregate. Such policy
shall name Tenant as an additional insured with respect to the common areas of
the Project.

               (ii) A policy of "all risk" or "causes of loss - special form"
property insurance on the Building, including the Tenant Improvements but
excluding Tenant's trade fixtures and equipment, in the amount of the full
replacement cost thereof as determined from time to time  by Landlord's
insurance agent, but in any event not less than every three years.

          (d) Notwithstanding any other provision of this Lease to the contrary,
Landlord and Tenant each hereby waive all rights of recovery against the other
on account of loss or damage occasioned to such waiving party for its property
or the property of others under its control to the extent that such loss or
damage is insured against under any insurance policies which may be in force at
the time of such loss or damage or which are required to be maintained by this
Lease, even if such damage may have been caused by the negligence of the other
party, its agents or employees.  Tenant and Landlord shall, upon obtaining
policies of insurance required hereunder, give notice to the insurance carrier
that the foregoing mutual waiver of subrogation is contained in this Lease and
Tenant and Landlord shall cause each insurance policy obtained by such party to
provide that the insurance company waives all right of recovery by way of
subrogation against either Landlord or Tenant in connection with any damage
covered by such policy.
 
                                  ARTICLE 21
                                  ----------
                             DAMAGE OR DESTRUCTION
                             ---------------------

          (a) If there is damage to the Premises which was caused by a peril
required to be covered or actually covered by insurance pursuant to Article 20
above ("Insured Loss"), or if there is damage to the Premises which is not an
Insured Loss but the estimated restoration cost is not more than ten percent
(10%) of the then actual replacement cost of the Premises, then, in either
event, Landlord shall repair such damage to the Premises (but not any damage to
Tenant's trade fixtures, equipment, furniture or other personal property) at
Landlord's expense, as promptly as possible, and this Lease shall continue in
full force and effect, except as otherwise provided below.

          (b) If there is damage to the Premises that is not an Insured Loss,
and the estimated restoration cost exceeds ten percent (10%) of the then actual
replacement cost of the Premises, then Landlord may, at Landlord's option,
either (i) repair such damage to the Premises (but not any damage to Tenant's
trade fixtures, equipment, furniture or other personal property), at Landlord's
expense, as promptly as possible, in which event this Lease shall continue in
full force and effect, or (ii) give notice to Tenant within thirty (30) days
after the date of the occurrence of such damage of Landlord's intention to
terminate this Lease as of the date of the occurrence of such damage.  If
Landlord elects to terminate this Lease, Tenant shall have the right, within ten
(10) days after receipt of such notice, to give Landlord notice of Tenant's
intention to pay for the cost to restore the Premises, in which event this Lease
shall continue in full force and effect and Landlord shall proceed to make such
repairs as soon as reasonably possible after Tenant has deposited with Landlord
an amount equal to (A) the estimated cost of such repairs less (B) ten percent
(10%) of the then actual replacement cost of the Premises.  Landlord shall be
responsible for such portion of the cost of the repairs equal to ten percent
(10%) of the then actual replacement cost of the Premises.  
<PAGE>
 
If Tenant does not give notice within such 10-day period, this Lease shall be
terminated as of the date of the occurrence of such damage.

          (c) Upon any termination of this Lease under any of  the provisions of
this Article 21, the parties shall be released without further obligation to the
other from the date possession of the Premises is surrendered to Landlord except
for items which have therefore accrued and are then unpaid.  If Landlord elects
to terminate this Lease under any of the provisions of this Article 21, Landlord
shall compensate Tenant for the loss of Tenant's leasehold interest, which shall
be determined as the date of the casualty in accordance with the schedule
attached as EXHIBIT G.  The foregoing shall not, however, create any legal or
            ---------                                                        
equitable property right in favor of Tenant unless and until Landlord terminates
this Lease as permitted under this Article 21.

          (d) In the event of repair, reconstruction and restoration by Landlord
as herein provided, the rental payable under this Lease shall be abated
proportionately with the degree to which Tenant's use of the Premises is
impaired during the period of such repair, reconstruction or restoration.
Tenant shall not be entitled to any compensation or damages for loss in the use
of the whole or any part of the Premises and/or any inconvenience or annoyance
occasioned by such damage, repair, reconstruction or restoration.

          (e) Notwithstanding anything to the contrary contained in this Article
21, if Landlord is delayed or prevented from completing the repair or
restoration of the damaged Premises within fifteen (15) months after the
occurrence of such damage or destruction by reason of acts of God, war,
governmental restrictions, inability to procure the necessary labor or
materials, or other cause beyond the reasonable control of Landlord, either
Landlord or Tenant may terminate this Lease as of the end of said fifteen (15)
month period.

          (f) If Landlord is obligated to or elects to repair or restore as
herein provided, Landlord shall be obligated to make repair or restoration only
of those portions of the Project and the Premises which were originally provided
at Landlord's expense, and the repair and restoration of items not provided at
Landlord's expense shall be the obligation of Tenant.

          (g) Notwithstanding anything to the contrary herein, if there is
damage to the Premises, whether or not an Insured Loss, which cannot be repaired
within one hundred eighty (180) days after the date of the casualty (the
"Estimated Rebuilding Period"), as reasonably estimated by an architect or
engineer jointly selected by Landlord and Tenant, Tenant shall have the right to
terminate this Lease as of the date of such damage.  Landlord and Tenant shall
use reasonable efforts to obtain a written estimate of the repair period within
thirty (30) days after the date of damage.  If Tenant desires to exercise its
termination option, Tenant shall give Landlord written notice of such exercise
within thirty (30) days after Tenant obtains written notice of the estimated
repair period.  If Landlord has not completed the restoration of the Premises
within sixty (60) days after the Estimated Rebuilding Period, Tenant shall have
the right to terminate this Lease upon written notice to Landlord given at any
time prior to the expiration of such 60-day period.  If Landlord is required or
elects to restore the Premises under the provisions of this Article 21 and does
not commence such restoration within one hundred twenty (120) days after the
date of such damage, Tenant may, at Tenant's option, terminate this Lease by
giving Landlord written notice thereof at any time prior to 
<PAGE>
 
the expiration of such 120-day period. In such event, this Lease shall terminate
as of the date of such notice to Landlord.

          (h) If at any time during the last year of the term of this Lease
there is a casualty to the Premises (whether or not an Insured Loss) such that
Tenant's use or occupancy of the Premises is materially impaired and the
Premises cannot be restored within thirty (30) days after the date of such
casualty, either Landlord or Tenant may terminate this Lease as of the date of
such casualty by written notice to the other within forty-five (45) days after
the date of the occurrence of such damage.  If, however, at the time of such
damage Tenant has an option to extend the term of this Lease and the time for
exercise of such option has not then expired, then Tenant shall have a period of
forty-five (45) days from the date of the casualty to elect to exercise the
option to extend by delivery of written notice to Landlord.  If Tenant exercises
such option during such 45-day period, and provided Landlord is otherwise
obligated to, or elects to repair such damage under the provisions of this
Article 21, Landlord shall, at Landlord's expense, repair such damage as soon as
reasonably possible, and this Lease shall continue in full force and effect.  If
Tenant fails to exercise such option during such 45-day period, then Landlord
may, at Landlord's option, terminate this Lease effective as of the date of the
casualty, giving notice to Tenant of Landlord's election to do so within ten
(10) days after the expiration of such 45-day period.

          (i) The provisions of California Civil Code 1932, Subsection 2, and
1933, Subsection 4, which permit termination of a lease upon destruction of the
Leased Premises, are hereby waived by Tenant; and the provisions of this Article
shall govern in case of such destruction.

                                  ARTICLE 22
                                  ----------
                                EMINENT DOMAIN
                                --------------

          In case all of the Premises, or such part thereof as shall
substantially interfere with Tenant's use and occupancy thereof, or all access
thereto, shall be taken for any public or quasi-public purpose by any lawful
power or authority by exercise of the right of appropriation, condemnation or
eminent domain, or sold to prevent such taking, either party shall have the
right to terminate this Lease effective as of the date possession is required to
be surrendered to said authority.  Tenant shall not assert any claim against
Landlord or the taking authority for any compensation because of such taking,
and Landlord shall be entitled to receive the entire amount of any award without
deduction for any estate or interest of Tenant, except that Landlord agrees that
Tenant shall be entitled to receive an amount which is not more than seven
percent (7%) of Landlord's award to compensate Tenant for the loss of Tenant's
leasehold interest.  In the event the amount of property or the type of estate
taken shall not substantially interfere with the conduct of Tenant's business,
in Tenant's good faith judgment, Landlord shall be entitled to the entire amount
of the award without deduction for any estate or interest of Tenant, Landlord
shall restore the Premises to substantially their same condition prior to such
partial taking, and a proportionate allowance shall be made to Tenant for the
rent corresponding to the time during which, and to the part of the Premises of
which, Tenant shall be so deprived on account of such taking and restoration.
Nothing contained in this paragraph shall be deemed to give Landlord any
interest in any award made to Tenant for the taking of personal property and
fixtures belonging to Tenant or for Tenant's relocation expenses.

                                  ARTICLE 23
                                  ----------
<PAGE>
 
                             DEFAULTS AND REMEDIES
                             ---------------------

          (a) The occurrence of any one or more of the following events shall
constitute a default hereunder by Tenant:

               (i) The abandonment of the Premises by Tenant.

               (ii) The failure by Tenant to make any payment of rent or
additional rent or any other payment required to be made by Tenant hereunder, as
and when due, where such failure shall continue for a period of seven (7) days
after written notice thereof from Landlord to Tenant; provided however, that any
such notice shall be in lieu of, and not in addition to, any notice required
under California Code of Civil Procedure Section 1161 regarding unlawful
detainer actions.

               (iii) The failure by Tenant to observe or perform any of the
express or implied covenants or provisions of this Lease to be observed or
performed by Tenant, other than as specified in Subparagraph 23(a)(i) or (ii)
above, where such failure shall continue for a period of thirty (30) days after
written notice thereof from Landlord to Tenant. Any such notice shall be in lieu
of, and not in addition to, any notice required under California Code of Civil
Procedure Section 1161 regarding unlawful detainer actions. If the nature of
Tenant's default is such that more than thirty (30) days are reasonably required
for its cure, then Tenant shall not be deemed to be in default if Tenant shall
commence such cure within said thirty-day period and thereafter diligently
prosecute such cure to completion.

               (iv) (1) The making by Tenant of any general assignment for the
benefit of creditors; (2) the filing by or against Tenant of a petition to have
Tenant adjudged a bankrupt or 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 within sixty days); (3) 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 days; or (4) 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 days.

               (v) A default by Tenant under the Sycamore Plaza II Lease
(subject to the provisions of paragraphs 24(f) and 35).

          (b) In the event of any such default by Tenant, 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.
In the event that Landlord shall elect to so terminate this Lease then Landlord
may recover from Tenant:

               (i) The worth at the time of award of any unpaid rent which had
been earned at the time of such termination; plus
<PAGE>
 
               (ii) The worth at the time of award of the amount by which the
unpaid rent which would have been earned after termination until the time of
award exceeds the amount of such rental loss that Tenant proves could have been
reasonably avoided; plus

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

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

As used in Subparagraph 23(b)(i) and (ii) above, the "worth at the time of
award" is computed by allowing interest at the maximum rate permitted by law.
As used in Subparagraph 23(b)(iii) above, the "worth at the time of award" is
computed by discounting such amount at the discount rate of the Federal Reserve
Bank of San Francisco at the time of award plus one percent.

          (c) 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.  No re-entry or taking possession of the Premises by Landlord
pursuant to this Paragraph 23(C) shall be construed as an election to terminate
this Lease unless a written notice of such intention is given to Tenant or
unless the termination thereof is decreed by a court of competent jurisdiction.

          (d) In the event of a default by Tenant under Paragraph 23(a)(iv)
above, the unenforceability of certain remedies to which Landlord may otherwise
be entitled under this Lease or at law shall not prevent Landlord from
exercising any other remedies that Landlord may have against Tenant for any
other default by Tenant including, without limitation, the right to draw upon
the letter of credit as provided in Article 5 of this Lease.

          (e) All rights, options and remedies of Landlord contained in this
Lease shall be constructed and held to be cumulative, and no one of them shall
be exclusive of the other, and Landlord shall have the right to pursue any one
or all of such remedies or any other remedy or relief which may be provided by
law, whether or not stated in this Lease.  No waiver of any default of Tenant
hereunder shall be implied from any acceptance by Landlord of any rent or other
payments due hereunder or any omission by Landlord to take any action on account
of such default if such default persists or is repeated, and no express waiver
shall affect defaults other than as specified in said waiver.  The consent or
approval of Landlord to or of any act by Tenant requiring Landlord's consent or
approval shall not be deemed to waive or render unnecessary Landlord's consent
or approval to or of any subsequent similar acts by Tenant.

          (f) The chronic delinquency by Tenant in the payment of Basic Rent or
any other payments required to be paid by Tenant under this Lease shall
constitute a default hereunder by Tenant.  "Chronic delinquency" shall mean
failure by Tenant to pay Basic Rent, or any other payments required to be paid
by Tenant under this Lease within seven (7) days after written notice 
<PAGE>
 
thereof for any three (3) occasions (consecutive or non-consecutive) during any
twelve (12) month period. In the event of a chronic delinquency, Landlord shall
have the right, at Landlord's option, to require that Basic Rent be paid by
Tenant quarterly, in advance.

          (g) Landlord shall not be deemed to be in default in the performance
of any obligation required to be performed by it hereunder unless and until it
has failed to perform such obligation within thirty (30) days after receipt of
written notice by Tenant to Landlord specifying the nature of such default, or
as soon as reasonably possible after notice from Tenant in the event that
Landlord's failure to perform its obligation will result in immediate threat of
personal injury or property damage.  If, however, the nature of Landlord's
obligation is such that more than thirty (30) days are required for its
performance, then Landlord shall not be deemed to be in default if it shall
commence such performance within such thirty (30) day period and thereafter
diligently prosecute the same to completion.

                                  ARTICLE 24
                                  ----------
                           ASSIGNMENT AND SUBLETTING
                           -------------------------

          (a) Tenant shall not voluntarily assign its interest in this Lease or
in the Premises, or sublease all or any part of the Premises, or allow any other
person or entity to occupy or use all or any part of the Premises, without first
obtaining Landlord's prior written consent which consent shall not be
unreasonably withheld.  Any assignment or sublease without Landlord's prior
written consent shall be voidable, at Landlord's election, and shall constitute
a default.  In no event shall Tenant be permitted to encumber this Lease or
Tenant's leasehold interest in the Premises.  No consent to any assignment or
sublease shall constitute a further waiver of the provisions of this paragraph.
Tenant shall notify Landlord in writing of Tenant's intent to sublease or assign
this Lease and Landlord shall, within thirty days of receipt of such written
notice, elect one of the following:

               (i) Consent to such proposed assignment or sublease;

               (ii) Refuse such consent, which refusal shall be on reasonable
grounds; or

               (iii) In the event of a proposed assignment, elect to terminate
this Lease, or in the event of a proposed sublease of all or any portion of the
Premises for the then remaining term of this Lease, elect to terminate this
Lease with respect to the portion of the Premises to be subleased.

          (b) As a condition for granting its consent to any assignment or
sublease, sixty days prior to any anticipated assignment or sublease Tenant
shall give Landlord written notice (the "Assignment Notice"), which shall set
forth the name, address and business of the proposed assignee or sublessee,
information (including references) concerning the character, ownership, and
financial condition of the proposed assignee or sublessee, and the Assignment
Date, any ownership or commercial relationship between Tenant and the proposed
assignee or sublessee, and the consideration of all other material terms and
conditions of the proposed assignment or sublease, all in such detail as
Landlord shall reasonably require.  If Landlord requests additional detail, the
Assignment Notice shall not be deemed to have been received until Landlord
receives such 
<PAGE>
 
additional detail, and Landlord may withhold consent to any assignment or
sublease until such additional detail is provided to it. Further, upon any
default by Tenant hereunder, Landlord may require that the sublessee or assignee
remit directly to Landlord on a monthly basis, all monies due to Tenant by said
assignee or sublessee.

          (c) The consent by Landlord to any assignment or subletting shall not
be construed as relieving Tenant or any assignee of this Lease or sublessee of
the Premises from obtaining the express written consent of Landlord to any
further assignment or subletting or as releasing Tenant or any assignee or
sublessee of Tenant from any liability or obligation hereunder whether or not
then accrued.  In the event Landlord shall consent to an assignment or sublease,
Tenant shall pay Landlord as Additional Rent a reasonable attorneys' and
administrative fee not to exceed $500 for costs incurred in connection with
evaluating the Assignment Notice.  This section shall be fully applicable to all
further sales, hypothecations, transfers, assignments and subleases of any
portion of the Premises by any successor or assignee of Tenant, or any sublessee
of the Premises.

          (d) As used in this section, the subletting of substantially all of
the Premises for substantially all of the remaining term of this Lease shall be
deemed an assignment rather than a sublease.  Notwithstanding the foregoing,
Landlord's consent shall not be required for any assignment or sublease to a
parent, subsidiary or affiliate of Tenant or to an entity resulting from a
merger, consolidation or reorganization, or any entity or person which acquires
all or substantially all of the assets or stock of Tenant, provided that, in the
event of an assignment, the assignee first executes, acknowledges and delivers
to Landlord an agreement whereby the assignee agrees to be bound by all of the
covenants and agreements in this Lease which Tenant has agreed to keep, observe
or perform, that the assignee agrees that the provisions of this section shall
be binding upon it as if it were the original Tenant hereunder and that if the
assignment is made in connection with a merger or other acquisition, the
assignee shall have a net worth (determined in accordance with generally
accepted accounting principles consistently applied) immediately after such
assignment which is at least equal to the net worth (as so determined) of Tenant
at the commencement of this Lease.

          (e) Except as provided above, Landlord's consent to any assignment or
sublease shall not be unreasonably withheld.  A condition to such consent shall
be delivery by Tenant to Landlord of a true copy of any such assignment or
sublease.  If for any proposed assignment or sublease Tenant receives rent or
other consideration, either initially or over the term of the assignment or
sublease, in excess of the rent called for hereunder, or, in case of the
sublease of a portion of the Premises, in excess of such rent fairly allocable
to such portion, after appropriate adjustments to assure that all other payments
called for hereunder are taken into account, Tenant shall pay to Landlord as
additional rent hereunder one-half (1/2) of the excess of each such payment of
rent or other consideration received by Tenant after first deducting any
reasonable and customary brokerage commission, attorney's fees, advertising
costs, tenant improvement costs and/or tenant improvement allowances paid by
Tenant in connection with the assignment or sublease.  Such excess shall be paid
to Landlord promptly after its receipt by Tenant.  Landlord's waiver or consent
to any assignment or subletting shall not relieve Tenant from any obligation
under this Lease and Tenant shall remain directly and primarily liable to
Landlord under this Lease for the full term hereof.  The parties intend that the
preceding sentence shall not apply to any sublease rentals respecting a portion
of the Premises that during the entire term of this Lease was not occupied by
Tenant for its own use, 
<PAGE>
 
but was always subleased by Tenant and/or kept vacant. For the purpose of this
section, the rent for each square foot of floor space in the Premises shall be
deemed equal.

          (f) If Landlord grants its consent to any assignment of this Lease as
provided in paragraph 24(a), the cross-default provision contained in paragraph
23(a)(v) of this Lease shall be automatically terminated as of the effective
date of such assignment.

                                  ARTICLE 25
                                  ----------
                                 SUBORDINATION
                                 -------------

          Without the necessity of any additional document being executed by
Tenant for the purpose of effecting a subordination, and at the election of
Landlord or any mortgagee with a lien on the Project or any ground lessor with
respect to the Project, this Lease shall be subject and subordinate at all times
to:

               (i) All ground leases or underlying leases which may now exist or
hereafter be executed affecting the Project or the land upon which the Project
is situated or both,

               (ii) The lien of any mortgage or deed of trust which may now
exist or hereafter be executed in any amount for which the Project, land, ground
leases or underlying leases, or Landlord's interest or estate in any of said
items is specified as security provided, however, that with respect to any
mortgage or deed of trust recorded against the Premises as of the Commencement
Date, Landlord obtains and delivers to Tenant prior to the Commencement Date a
non-disturbance and attornment agreement, in a form reasonably acceptable to
Tenant, executed by the holder of any such mortgage or deed of trust which
provides that in the event of any foreclosure of the mortgage or deed of trust,
or deed in lieu of foreclosure, this Lease shall not be terminated so long as
Tenant is not in default hereunder beyond any applicable grace or cure period
provided for herein. Concurrently with the execution of this Lease by Landlord,
Landlord shall obtain and deliver to Tenant a Subordination, Non-Disturbance and
Attornment Agreement in the form attached as EXHIBIT H, executed by Landlord and
                                             ---------                          
Principal Mutual Life Insurance Company. Notwithstanding the foregoing, Landlord
shall have the right to subordinate or cause to be subordinated any such ground
leases or underlying leases or any such liens to the Lease. In the event that
any ground lease or underlying lease terminates for any reason or any mortgage
or deed of trust is foreclosed or a conveyance in lieu of foreclosure is made
for any reason, Tenant shall, notwithstanding any subordination, attorn to and
become the Tenant of the successor in interest to Landlord, provided such
successor assumes in writing Landlord's obligations hereunder. Tenant covenants
and agrees to execute and deliver, within ten (10) days after written request by
Landlord, and in the form requested by Landlord, any additional documents
evidencing the priority or subordination of this Lease with respect to any such
ground leases or underlying leases or the lien of any such mortgage or deed of
trust so long as such document is reasonably satisfactory Tenant and provides
for the non-disturbance of Tenant upon any termination of such ground lease or
any foreclosure of the mortgage or deed of trust as described herein.

               (iii)  The CC&R's as described in Article 6.

                                  ARTICLE 26
                                  ----------
<PAGE>
 
                             ESTOPPEL CERTIFICATE
                             --------------------

          (a) Within ten days following any written request from the other,
Tenant or Landlord shall execute and deliver to the other a statement
certifying:

               (i) The date of commencement of this Lease;

               (ii) The fact that this Lease is unmodified and in full force and
effect (or, if there have been modifications hereto, that this Lease is in full
force and effect, and stating the date and nature of such modifications);

               (iii)  The date to which the rental and other sums payable
under this Lease have been paid;

               (iv) That there are no current defaults under this Lease by
either Landlord or Tenant except as specified in the responding party's
statement; and

               (v) Such other matters reasonably requested by Landlord or
Tenant, as applicable.

Landlord and Tenant intend that any statement delivered pursuant to this Article
26 may be relied upon by any mortgagee, beneficiary, purchaser or prospective
purchaser of the Building or Project or any interest therein, or any equipment
lessor or purchaser of Tenant's stock or any assets of Tenant, as the case may
be.

          (b) Tenant's or Landlord's failure to deliver such statement within
such time shall be conclusive upon such party, as the case may be:

               (i) That this Lease is in full force and effect, without
modification except as may be represented by the requesting party,

               (ii) That there are no uncured defaults in the requesting
party's performance, and

               (iii)  That not more than one month's rental has been paid in
advance.

                                  ARTICLE 27
                                  ----------
                                    SIGNAGE
                                    -------

          (a) Subject to the receipt of all necessary approvals from the City of
Pleasanton, Tenant shall have the right to install two (2) Tenant identification
signs on the exterior of the Building and to have its name placed on the
monument tombstone at the entry to the Project.  The exact location of such
signs shall be agreed to by Landlord and Tenant, subject to any restrictions
imposed by the City of Pleasanton and the CC&R's.  The size, design and other
physical characteristics of Tenant's signage shall be subject to the Design
Guidelines imposed by the 
<PAGE>
 
CC&R's. The cost of such signs, including installation, maintenance and repair,
shall be paid by Tenant. Tenant shall have no other right to maintain a Tenant
identification sign in any other location in, on or about the Premises, the
Project, or Bernal Corporate Park and shall not display or erect any Tenant
identification sign, display or other advertising material within the Premises
that is visible from the exterior of the Building. If Tenant fails to maintain
its exterior signage or if Tenant fails to remove such signage upon termination
of this Lease, Landlord may do so at Tenant's expense and Tenant's reimbursement
to Landlord for such amounts shall be deemed additional rent.

          (b) The rights  to such exterior building signage and monument signage
are personal to Documentum, Inc. and may not be transferred or assigned except
to (i) a parent, subsidiary or affiliate of Documentum, Inc., or (ii) a
transferee approved in writing by Landlord pursuant to paragraph 24(a)(i) of
this Lease; provided, however, that if Landlord, in its good faith judgment and
reasonable opinion determines that any transferee approved by Landlord is not of
reputable or good character, consistent with the other tenants of the Project,
Landlord may deny such sign rights to such transferee if Landlord so notifies
Tenant in writing at the time of Landlord's consent to the proposed transfer.
If Landlord fails to so notify Tenant, the transferee approved by Landlord shall
be entitled to the same signage rights granted to Documentum, Inc. hereunder.

                                  ARTICLE 28
                                  ----------
                             RULES AND REGULATIONS
                             ---------------------

          Tenant shall faithfully observe and comply with the "Rules and
Regulations," a copy of which is attached hereto and marked EXHIBIT D,  and all
                                                            ---------          
reasonable and nondiscriminatory modifications thereof and additions thereto
from time to time put into effect by Landlord.  Landlord shall not be
responsible to Tenant for the violation or non-performance by any other tenant
or occupant of the Project of any of said Rules and Regulations.

                                  ARTICLE 29
                                  ----------
                               CONFLICT OF LAWS
                               ----------------

          This Lease shall be governed by and construed pursuant to the laws of
the State of California.

                                  ARTICLE 30
                                  ----------
                            SUCCESSORS AND ASSIGNS
                            ----------------------

          Except as otherwise provided in this Lease, all of the covenants,
conditions and provisions of this Lease shall be binding upon and shall inure to
the benefit of the parties hereto and their respective heirs, personal
representatives, successors and assigns.

                                  ARTICLE 31
                                  ----------
                             SURRENDER OF PREMISES
                             ---------------------

          The voluntary or other surrender of this Lease by Tenant, or a mutual
cancellation thereof, shall not work a merger, and shall, at the option of
Landlord, operate as an assignment to it of any or all subleases and
subtenancies.
<PAGE>
 
                                  ARTICLE 32
                                  ----------
                                ATTORNEYS' FEES
                                ---------------

          If either Landlord or Tenant brings any action for any relief against
the other arising out of this Lease, the losing party shall pay to the
prevailing party its reasonable attorneys' fees and costs.(including attorneys'
fees on appeal, and costs and expenses incurred in out-of-court negotiations,
workouts and/or settlements or in seeking relief from stay or otherwise seeking
to protect its rights in any bankruptcy proceeding).  In addition, the
prevailing party shall be entitled to its attorneys' fees, costs and expenses
incurred in post-judgment proceedings to collect and enforce a judgment.  This
provision is separate and several and shall survive the merger of this Lease
into any judgment on this Lease

                                    ARTICLE 33
                                    ----------
                         PERFORMANCE BY TENANT
                         ---------------------

          All covenants and agreements to be performed by Tenant under any of
the terms of this Lease shall be performed by Tenant at Tenant's sole cost and
expense and without any abatement of rent, except as otherwise expressly
provided herein.  If Tenant shall fail to pay any sum of money owed to any party
other than Landlord, for which it is liable hereunder or if Tenant shall fail to
perform any other act on its part to be performed hereunder and such failure
shall continue for ten (10) days after written notice thereof by Landlord (or
such longer period as may be expressly provided for in this Lease), Landlord
may, without waiving or releasing Tenant from obligations of Tenant, but shall
not be obligated to, make any such payment or perform any such other act to be
made or performed by Tenant.  All sums so paid by Landlord and all necessary
incidental costs shall be payable to Landlord within ten (10) days after demand
therefor.  Tenant covenants to pay any such sums and Landlord shall have (in
addition to any other right or remedy of Landlord) all rights and remedies in
the event of the non-payment thereof by Tenant as are set forth in Article 23
hereof.

                                  ARTICLE 34
                                  ----------
                             MORTGAGEE PROTECTION
                             --------------------

          In the event of any default on the part of Landlord, Tenant will give
notice by registered or certified mail to any beneficiary of a deed of trust or
mortgage covering the Premises whose address shall have been furnished to
Tenant.  Such beneficiary or mortgagee shall have thirty (30) days after receipt
of written notice from Tenant specifying the nature of Landlord's default to
cure such default; provided, however, that if the nature of Landlord's
obligation is such that more than thirty (30) days are required for its
performance, then such beneficiary or mortgagee shall have such additional time
as is reasonably necessary to cure such default so long as it commences such
performance within such thirty (30) day period and thereafter diligently
prosecute the same to completion.

                                  ARTICLE 35
                                  ----------
                            DEFINITION OF LANDLORD
                            ----------------------
<PAGE>
 
          The term "Landlord", as used in this Lease, so far as covenants or
obligations on the part of Landlord are concerned, shall be limited to mean and
include only the owner or owners, at the time in question, of the fee title of
the Premises or the lessees under any ground lease, if any.  In the event of any
transfer, assignment or other conveyance or transfers of any such title,
Landlord herein named (and in case of any subsequent transfers or conveyances,
the then grantor) shall be automatically freed and relieved from and after the
date of such transfer, assignment or conveyance of all liability as respects the
performance of any covenants or obligations on the part of Landlord contained in
this Lease thereafter to be performed.  Without further agreement, the
transferee of such title shall be deemed to have assumed and agreed to observe
and perform any and all obligations of Landlord hereunder, during its ownership
of the Premises.  Landlord may transfer its interest in the Premises without the
consent of Tenant and such transfer or subsequent transfer shall not be deemed a
violation on Landlord's part of any of the terms and conditions of this Lease.
In the event that Landlord transfers or conveys the Project to a third party
(other than a parent, subsidiary or affiliate of Landlord) and either retains
title to the project known as Sycamore Plaza II or transfers or conveys title to
Sycamore Plaza II to another third party (other than a parent, subsidiary or
affiliate of Landlord) the cross-default provisions set forth in paragraph
23(a)(v) shall be automatically terminated as of the date of such transfer or
conveyance.

                                  ARTICLE 36
                                  ----------
                                    WAIVER
                                    ------

          The waiver by Landlord or Tenant of any breach of any term, covenant
or condition herein contained shall not be deemed to be a waiver of any
subsequent breach of the same or any other term, covenant or condition herein
contained, nor shall any custom or practice which may grow up between the
parties in the administration of the terms hereof be deemed a waiver of or in
any way affect the right of Landlord or Tenant to insist upon the performance by
the other in strict accordance with said terms.  The subsequent acceptance of
rent hereunder by Landlord shall not be deemed to be a waiver of any preceding
breach by Tenant or any term, covenant or condition of this Lease, other than
the failure of Tenant to pay the particular rent so accepted, regardless of
Landlord's knowledge of such preceding breach at the time of acceptance of such
rent.

                                  ARTICLE 37
                                  ----------
                           IDENTIFICATION OF TENANT
                           ------------------------

          If more than one person executes this Lease as Tenant:

              (i)    Each of them is jointly and severally liable for the
keeping, observing and performing of all of the terms, covenants, conditions,
provisions and agreements of this Lease to be kept, observed and performed by
Tenant, and

              (ii)   The term "Tenant" as used in this Lease shall mean and
include each of them jointly and severally. The act of or notice from, or notice
to refund to, or the signature of any one or more of them, with respect to the
tenancy of this Lease, including, but not limited to any renewal, extension,
expiration, termination or modification of this Lease, shall be binding upon
each and all of the persons executing this Lease as Tenant with the same force
and effect as if each and all of them had so acted or so given or received such
notice or refund or so signed.
<PAGE>
 
                                  ARTICLE 38
                                  ----------
                                    PARKING
                                    -------

          The use by Tenant, its employees and invitees, of the parking
facilities of the Project shall be on the terms and conditions set forth in
EXHIBIT E attached hereto and by this reference incorporated herein and shall be
---------                                                                       
subject to such other agreement between Landlord and Tenant as may hereinafter
be established.  Tenant, its employees and invitees shall use no more than four
(4) non-exclusive parking spaces per one thousand (1,000) rentable square feet
of leased space.  Tenant's total parking allocation for the Premises and the
premises at 6701 Koll Center Parkway shall include twenty (20) parking spaces
designated as visitor parking for the exclusive use of Tenant's visitors, which
shall be located near the entrances to the Premises and the building at 6701
Koll Center Parkway, with no more than five (5) of such visitor parking spaces
to be located at the entrance to the building at 6701 Koll Center Parkway.
Tenant's visitor parking spaces at 6701 Koll Center Parkway shall be located in
a manner that will permit a reasonable number of additional visitor parking
spaces near the entrance to the building for other tenants of the building.
Tenant's use of the parking spaces shall be confined to the Project.  If, in
Landlord's reasonable business judgment, it becomes necessary, Landlord shall
exercise due diligence to cause the creation of cross-parking easements and such
other agreements as are necessary to permit Tenant, its employees and invitees
to use parking spaces on the properties and buildings of Bernal Corporate Park,
which are separate legal parcels from the Project.  Tenant acknowledges that
other tenants of the Project and the tenants of the other buildings, their
employees and invitees, may be given the right to park at the Project.

                                  ARTICLE 39
                                  ----------
                              TERMS AND HEADINGS
                              ------------------

          The words "Landlord" and "Tenant" as used herein shall include the
plural as well as the singular.  Words used in any gender include other genders.
The paragraph headings of this Lease are not a part of this Lease and shall have
no effect upon the construction or interpretation of any part hereof.

                                  ARTICLE 40
                                  ----------
                             EXAMINATION OF LEASE
                             --------------------

          Submission of this instrument for examination or signature by Tenant
does not constitute a reservation of or option for lease, and it is not
effective as a lease or otherwise until execution by and delivery to both
Landlord and Tenant.

                                  ARTICLE 41
                                  ----------
                                     TIME
                                     ----

          Time is of the essence with respect to the performance of every
provision of this Lease in which time or performance is a factor.

                                  ARTICLE 42
                                  ----------
<PAGE>
 
                          PRIOR AGREEMENT: AMENDMENTS
                          ---------------------------

          This Lease contains all of the agreements of the parties hereto with
respect to any matter covered or mentioned in this Lease, and no prior agreement
or understanding pertaining to any such matter shall be effective for any
purpose.  No provisions of this Lease may be amended or added to except by an
agreement in writing signed by the parties hereto or their respective successors
in interest.

                                  ARTICLE 43
                                  ----------
                                 SEPARABILITY
                                 ------------

          Any provision of this Lease which shall prove to be invalid, void or
illegal in no way affects, impairs or invalidates any other provision hereof,
any such other provisions shall remain in full force and effect.

                                  ARTICLE 44
                                  ----------
                                  RECORDING
                                  ---------

          Promptly following full execution of this Lease, Landlord and Tenant
shall execute a short form memorandum of this Lease mutually acceptable to
Landlord and Tenant.  Tenant shall be permitted to record such memorandum at
Tenant's expense.  Tenant shall, within ten (10) days after written request by
Landlord, execute and deliver to Landlord a quitclaim deed in recordable form
and prepared by Landlord, quitclaiming, releasing and remising to Landlord any
right, title and interest of Tenant in and to the Premises and the Project
pursuant to this Lease.

                                   ARTICLE 45
                                   ----------
                                    CONSENTS
                                    --------

          Whenever the consent of either party is required hereunder such
consent shall not be unreasonably withheld.

                                  ARTICLE 46
                                  ----------
                            LIMITATION ON LIABILITY
                            -----------------------

          In consideration of the benefits accruing hereunder, Tenant and all
successors and assigns covenant and agree that, in the event of any actual or
alleged failure, breach or default under this Lease by Landlord:

          (a)  The sole and exclusive remedy shall be against the Landlord's
interest in the Project;

          (b)  No partner, officer, agent or employee of Landlord shall be sued
or named as a party in any suit or action (except as may be necessary to secure
jurisdiction of Landlord);
<PAGE>
 
          (c)  No service or process shall be made against any partner, officer,
agent or employee of Landlord (except as may be necessary to secure jurisdiction
of Landlord);

          (d)  No partner, officer, agent or employee of Landlord shall be
required to answer or otherwise plead to any service of process;

          (e)  No judgment will be taken against any partner, officer, agent or
employee of Landlord;

          (f)  Any judgment taken against any partner, officer, agent or
employee of Landlord may be vacated and set aside at any time nunc pro nunc;

          (g)  No writ of execution will ever be levied against the assets of
any partner, officer, agent or employee of Landlord;

          (h)  The covenants and agreements set forth in this Article 46 are
enforceable both by Landlord and also by any  partner, officer, agent or
employee of Landlord.

                                  ARTICLE 47
                                  ----------
                                    RIDERS
                                    ------

          Clauses, plats and riders, if any, signed by Landlord and Tenant and
affixed to this Lease are a part hereof.

                                  ARTICLE 48
                                  ----------
                                   EXHIBITS
                                   --------

          All Exhibits attached hereto are incorporated into this Lease.

                                  ARTICLE 49
                                  ----------
                            MODIFICATION FOR LENDER
                            -----------------------

          If, in connection with obtaining construction, interim or permanent
financing for the Project the lender shall request reasonable modifications in
this Lease as a condition to such financing, Tenant will not unreasonably
withhold, delay or defer its consent thereto, provided that such modifications
do not increase the obligations of Tenant hereunder or materially adversely
affect the leasehold interest hereby created or Tenant's rights hereunder.

                                 ARTICLE 50
                                 ----------
                             WAIVER OF LIEN RIGHTS
                             ---------------------

          Notwithstanding anything in this Lease to the contrary, Landlord
waives any right, title and interest Landlord now has, or may hereafter have,
whether statutory or otherwise, to any trade fixtures, equipment, furniture,
signs, books and records, inventory or other personal property of Tenant
(singly, and/or collectively, "Collateral").  Landlord further agrees that
Tenant shall have the right to mortgage, pledge, hypothecate or grant a security
interest in any such Collateral as security for its obligations under any future
equipment lease or other financing arrangement related 
<PAGE>
 
to the conduct of Tenant's business at the Premises. Landlord further agrees to
execute and deliver any UCC filing statement or other documentation reasonably
acceptable to Landlord that may be required to subordinate Landlord's interest
in the Collateral in connection with any such future lease or financing
arrangement, including, but not limited to, any real estate consent or waiver
forms reasonably acceptable to Landlord, including those submitted by any
vendors, equipment lessors or chattel mortgagees. All trade fixtures, signs,
equipment, furniture, or other personal property of whatever kind or nature kept
or installed at the Premises by Tenant may be removed by Tenant in the ordinary
course of business at any time and from time to time during the term of this
Lease. Landlord shall further acknowledge that the property covered by the
consent or waiver forms may be removed from the Premises by the vendor,
equipment lessor or chattel mortgagee at any time prior to termination of this
Lease upon any default by Tenant in the terms of such lease, chattel mortgage or
similar documents, free and clear of any claim or lien of Landlord in and to
such property provided that such lessor or mortgagee agrees in writing to give
Landlord prior notice of any intended removal and to be responsible for the
repair of any damage to the Premises caused by such removal.
 

                                 ARTICLE 51
                                 ----------
                               OPTION TO EXTEND
                               ----------------

          Provided that Tenant is not in default hereunder, either at the time
of exercise or at the time the extended term commences, Tenant shall have the
option to extend the initial seven (7) year term of this Lease for one (1)
additional period of five (5) years ("Option Period") on the same terms,
covenants and conditions provided herein, except that upon such renewal the
Basic Rent due hereunder shall be the then fair market rental value of the
Premises.  The then fair market rental value of the Premises' shall be defined
to mean the fair market rental value of the Premises as of the commencement of
the Option Period, taking into consideration the uses permitted under this
Lease, the quality, size, design and location of the Premises, and the rent for
comparable space located in Pleasanton.  Tenant shall exercise its option by
giving Landlord written notice ("Option Notice") at least two hundred seventy
(270) days but not more than three hundred sixty (360) days prior to the
expiration of the initial term of this Lease.  This option to extend is personal
to Tenant and may not be transferred or assigned to any third party, except
Tenant affiliates and permitted transferees pursuant to Article 24 of this
Lease.
<PAGE>
 
                                 ARTICLE 52
                                 ----------
                            LANDLORD'S CONDITION
                            -------------------- 

          This Lease is subject to the approval of Landlord's investment
committee which Landlord shall use diligent efforts to obtain no later than ten
(10) business days after this Lease has been fully executed.  This condition is
for the sole benefit of Landlord and may be waived or deemed satisfied at
Landlord at Landlord's option.

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

LANDLORD:

Patrician Associates, Inc., a                Its:______________________________
California corporation 
                                             By:_______________________________
                                             Its:______________________________


By:_________________________________
Its:________________________________

By:_________________________________
Its:________________________________


TENANT:

Documentum, Inc., a California corporation

By:_________________________________
<PAGE>
 
ADDRESS:

Patrician Associates, Inc.
c/o Parkway Properties, Inc.,           ADDRESS:                         
7011 Koll Center,  Suite 210                                             
Pleasanton, California  94566           Documentum, Inc.                 
                                        5671 Gibraltar Drive             
                                        Pleasanton, California 94588-8547 


















 
                                   EXHIBIT A
                                   ---------
<PAGE>
 
                        OUTLINE OF TENANT'S FLOOR PLAN
                        ------------------------------




















                                   EXHIBIT A
                                   ---------
<PAGE>
 
                                  THE PROJECT
                                  -----------













                                   EXHIBIT A-1
                                   -----------
<PAGE>
 
                             WORK LETTER AGREEMENT
                             ---------------------

                                   RECITALS

     A.   Concurrently with the execution of this Work Letter Agreement ("Work
Letter"), Landlord and Tenant have entered into a lease (the "Lease") covering
certain premises (the "Premises") more particularly described in EXHIBIT A
                                                                 ---------
attached to the Lease.  This Work Letter is attached to and made a part of the
Lease.  The capitalized terms used herein shall have the meanings set forth in
the Lease, unless otherwise defined herein.

     B.  In order to induce Tenant to enter into the Lease and in consideration
of the mutual covenants hereinafter contained, Landlord and Tenant hereby agree
as follows with respect to the construction of the Base Building and the Tenant
Improvements (defined below):

     1.  COMPLETION SCHEDULE

          Within thirty (30) days after the full execution of this Lease,
Landlord shall deliver to Tenant, for Tenant's review and approval, a schedule
(the "Work Schedule") setting forth a timetable for the planning and completion
of the Base Building and the installation of the Tenant Improvements to be
constructed in the Premises.  The Work Schedule shall set forth each of the
various items of work to be done by or approval to be given by Landlord and
Tenant in connection with the completion of the Base Building and the Tenant
Improvements.  Such schedule shall be submitted to Tenant for its approval and,
upon approval by both Landlord and Tenant, such schedule shall become the basis
for completing the Base Building and the Tenant Improvements.  If Tenant shall
fail to approve the Work Schedule, as it may be modified after discussions
between Landlord and Tenant, within seven (7) working days after the date such
schedule is first received by Tenant, the Work Schedule shall be deemed
approved.

     2.  BASE BUILDING

          Landlord shall construct at Landlord's sole expense the building shell
and improvements, including the Site Improvements defined below, but excluding
the Tenant Improvements, to be constructed at 6801 Koll Center Parkway
(collectively, the "Base Building") in all material respects in accordance with
the drawings prepared by Korth Sunseri Hagey for Sycamore Plaza, project 96108,
including  sheets A0.1 through A11.2 dated May 22, 1998, sheets S1.1 through
S4.5, E0.1 through E2.1, M2.3, P0.1 through 6.1, all dated May 15, 1998; Kier &
Wright topographic drawing C.1 dated April 30, 1998, and grading and paving
plans, notes and details C.2 through C.7 dated April 30, 1998; landscape
drawings by David Gates and Associates, sheets L0.1 through L4.1 dated May 19,
1998; and Korth Sunseri Hagey Project Manual, including specifications dated
May, 1998 (collectively, the "Base Building Plans").  The Base Building shall
include, without limitation, the building lobby (including all restrooms),
interior stairways, elevator, central HVAC system, and sprinkler system
distribution, including upright heads, and, subject to receipt of all necessary
approvals from the City of Pleasanton, a covered walkway at ground level between
the Building and the building at 6701 Koll Center Parkway.  HVAC distribution
from the 

                                   EXHIBIT B
                                   ---------
                                  Page 1 of 8
<PAGE>
 
main trunk line shall be a Tenant Improvements Cost as described below. Landlord
shall complete construction of the Base Building in a good and workmanlike
manner in compliance with all Applicable Laws and the building permit issued by
the City of Pleasanton for such construction. For purposes of this Work Letter,
the Site Improvements shall mean the parking areas, driveways, walkways,
landscaping and other improvements to the common areas of the Project that are
depicted on the site plan attached as EXHIBIT B-1 hereto and incorporated
                                      -----------           
herein.

     3.  TENANT IMPROVEMENTS

          Reference herein to "Tenant Improvements" shall include all work to be
done in the Premises pursuant to the Tenant Improvement Plans described in
Paragraph 5 below, including but not limited to partitioning, doors, ceilings,
floor coverings, finishes, (including paint and wallcovering) electrical,
(including lighting, switching, outlets, etc.) plumbing, heating, ventilating
and air conditioning, fire protection, cabinets and other mill work, all as more
particularly described therein

     4.  TENANT'S SPACE PLAN

          Tenant shall retain a space planner to prepare preliminary and final
space plans required in connection with the construction of the Tenant
Improvements to the Premises.  Tenant shall cause its space planner to prepare
and submit to Landlord, no later than September 15, 1998, a final space plan for
Tenant's proposed Tenant Improvements to the Premises ("Space Plan").  Tenant's
Space Plan shall be sufficient to enable the Architect to prepare working
drawings for the Tenant Improvements pursuant to paragraph 5 below.  Within ten
(10) business days after receipt of Tenant's Space Plan, Landlord shall notify
Tenant of Landlord's approval or disapproval thereof, specifying in reasonable
detail the basis for Landlord's disapproval, if applicable.  The architect
("Architect") shall be selected by Tenant from among the following firms:
Interform; Ambiance Associates, Gensler and Associates; Korth, Sunseri and
Hagey; RMW and Associates; Michael Willis & Associates; or other similarly
qualified architect approved by Landlord.

     5.  FINAL PRICING AND DRAWING SCHEDULE

          (a) After the preparation of the Space Plan and after Landlord's
written approval thereof, in accordance with the Work Schedule, Landlord enter
into a contract with the Architect and shall cause the Architect to prepare and
submit to Tenant the final working drawings and specifications ("Tenant
Improvement Plans").  Such working drawings shall be approved by Landlord and
Tenant in accordance with the Work Schedule.  If Tenant disapproves any part of
the Tenant Improvement Plans, Tenant's disapproval shall provide objections with
sufficient particularity for the Architect to revise the Tenant Improvements
Plans.  Such revisions shall be subject to Landlord's approval, which shall not
be unreasonably withheld.  Following final approval of the Tenant Improvement
Plans by Landlord and Tenant, such plans be submitted by Landlord to the
appropriate governmental body for plan checking and a building permit.

                                   EXHIBIT B
                                   ---------
                                  Page 2 of 8
<PAGE>
 
          (b) Concurrent with the plan checking, Landlord shall cause Devcon
Construction (the "General Contractor") to prepare and deliver to Landlord and
Tenant a final pricing for construction of the Tenant Improvements ("Final
Pricing"), taking into account any modifications which may be required to
reflect changes in the plans and specifications required by the City of
Pleasanton.  Prior to determining the Final Pricing, Landlord shall cause the
General Contractor to solicit bids from three (3) subcontractors for each of the
subtrades, including final clean-up.  Tenant shall have the right to nominate
one subcontractor to bid each of the subtrades, provided that the subcontractors
nominated by Tenant are licensed, qualified contractors experienced with jobs of
similar size and complexity and provided that such subcontractors are signatory
to appropriate labor unions.  Additionally, Tenant shall have the right to
review the bid documentation package to ensure that it allows for competitive
bidding.  If Landlord selects a subcontractor for any subtrade whose bid is five
percent (5%) greater than the lowest bid obtained by Landlord for such subtrade,
that is otherwise comparable in scope and quality to the lowest bid, then
Landlord shall be responsible for that portion of the bid in excess of one
hundred five percent (105%) of the lowest bid, which excess amount shall not be
included in the cost of the Tenant Improvements for the purpose of allocating
the same between Landlord and Tenant pursuant hereto.

          (c) Landlord shall deliver the Final Pricing, including a line item
detailed breakdown, to Tenant for Tenant's review and approval.  The Final
Pricing shall include the General Contractor's overhead and profit (not to
exceed 2.75% of the total hard construction costs, which excludes permits and
fees, plans and testing and inspections), and general conditions (not to exceed
$71,808.00) which includes supervision and clean-up during construction
(excluding final clean-up).  Landlord agrees that if Tenant reasonably deems any
subcontractor trade item to be excessively high, Landlord will cause such trade
to be rebid, but in such event any delays attributable to or resulting from such
rebidding shall be considered a Tenant Delay as described in paragraph 8(b)
below.  Tenant shall, within ten (10) business days after receipt of the Final
Pricing, notify Landlord in writing of Tenant's approval or disapproval of the
Final Pricing, which will include specific terms objected to and the reasons
therefor, if applicable.  If Tenant disapproves the Final Pricing, Landlord and
Tenant will promptly meet to discuss modifications to the Tenant Improvement
Plans and the Final Pricing.

     6.  CONSTRUCTION OF TENANT IMPROVEMENTS

          (a) After the Tenant Improvement Plans and the Final Pricing have been
approved by Landlord and Tenant and Landlord has obtained a building permit for
the Tenant Improvements, Landlord shall enter into a construction contract with
the General Contractor for installation of the Tenant Improvements in accordance
with the Tenant Improvement Plans.  Landlord shall supervise the completion of
such work and shall use diligent efforts to secure completion of the work in
accordance with the Work Schedule and this Work Letter.

          (b) Landlord shall complete construction of the Tenant Improvements in
a good and workmanlike manner in compliance with all Applicable Laws and the
building permit issued by the City of Pleasanton for such construction.
Landlord shall correct any latent defects in the Tenant Improvements and/or the
Base Building and any other incomplete or defective items that

                                   EXHIBIT B
                                   ---------
                                  Page 3 of 8
<PAGE>
 
were not reasonably discoverable by Tenant during Tenant's walk-through
inspection of the Premises.

     7.  PAYMENT OF COST OF THE TENANT IMPROVEMENTS

          (a) Landlord shall provide Tenant with an allowance of Seven Hundred
Forty-Four Thousand Seven Hundred Thirteen and no/100ths Dollars ($744,713.00)
for the design and construction of the Tenant Improvements to the Premises
("Tenant Improvement Allowance").  Tenant shall pay to Landlord the sum of Two
Million Five Hundred Thousand and no/100ths Dollars ($2,500,000.00) as Tenant's
contribution toward the Tenant Improvement Costs ("Tenant's Contribution").
Tenant shall pay Tenant's Contribution to Landlord in cash upon execution of the
Lease.  Any Tenant Improvement Costs in excess of the Tenant Improvement
Allowance plus Tenant's Contribution hall be paid by Tenant in cash within
thirty (30) days after Landlord has provided Tenant with an itemized invoice for
such additional costs, provided that such additional costs are not caused by a
Landlord Delay.  In addition to the Tenant Improvement Allowance, Landlord shall
provide, at Landlord's expense, data communications conduit between the Premises
and the building at 6701 Koll Center Parkway and between these two (2) buildings
and the buildings known as Bernal Corporate Plaza I and II.

          (b) Tenant's Contribution shall be non-refundable to Tenant except as
provided in paragraph 2(d) of the Lease.  Landlord shall not be required to keep
Tenant's Contribution in a separate account or otherwise segregated from
Landlord's funds and Tenant shall not be entitled to any interest on Tenant's
contribution.  Furthermore, in the event of any default by Tenant under this
Lease that occurs at any time prior to the Commencement Date, specifically
including any default that occurs at any time prior to commencement of
construction of the Base Building and/or the Tenant Improvements, Landlord shall
be entitled to retain the entire amount of Tenant's Contribution to compensate
Landlord for damages resulting from Tenant's default.  In no event, however,
shall Tenant's Contribution be deemed liquidated damages nor shall Landlord's
retention of Tenant's Contribution prevent Landlord from exercising any other
right or remedy provided by this Lease or by law and such retention shall not
operate as a limitation on any recovery to which Landlord may otherwise be
entitled.

          (c) The Tenant Improvement Allowance and Tenant's Contribution may be
used for the following costs ("Tenant Improvement Costs"):

                 (i)    Payment of the cost of preparing the space plan (not to
exceed $0.15 per square foot) and the services of the Architect, including
preparation of the final working drawings and specifications, mechanical,
electrical and structural drawings, and all other aspects of the Tenant
Improvement Plans (not to exceed $0.85 per square foot);

                 (ii)   The payment of permit and license fees relating to
construction of the Tenant Improvements;

                 (iii)  A project management fee equal to $129,788.52 (four
percent (4%) of ($26.50 x 122,442 sq. ft.));


                                   EXHIBIT B
                                  -----------
                                  Page 4 of 8
<PAGE>
 
                 (iv) Construction of the Tenant Improvements, including,
without limitation, the following:
                      (1) Installation within the Premises of all partitioning,
doors, floor coverings, finishes, ceilings, wall coverings and painting,
millwork and similar items;

                      (2) All electrical wiring, lighting fixtures, outlets and
switches, and other electrical work to be installed within the Premises;

                      (3) The furnishing and installation of all duct work,
terminal boxes, defusers and accessories required for the completion of the
heating, ventilation and air conditioning systems within the Premises, including
the cost of meter and key control for after-hour air conditioning;

                      (4) Any additional Tenant requirements including, but not
limited to odor control, special heating, ventilation and air conditioning,
noise or vibration control or other special systems;

                      (5) All fire and life safety control systems such as fire
walls, sprinklers, halon, fire alarms, including piping, wiring and accessories
installed within the Premises;

                      (6) All plumbing, fixtures, pipes, and accessories to be
installed within the Premises; and

                      (7) Landlord shall provide telephone conduit only from the
telephone jacks in the walls to the top of the ceiling at those locations
specified in the Tenant Improvement Plans. Tenant shall be responsible for
pulling all wires from the service boards to the individual jacks.

          (d) If the Tenant Improvement Costs (as determined by the Final
Pricing approved by Landlord and Tenant) exceed the Tenant Improvement Allowance
plus Tenant's Contribution, one-half (1/2) of the excess costs shall be paid by
Tenant to Landlord in cash within thirty (30) days after Landlord has provided
Tenant with an itemized invoice for such excess costs, and the balance shall be
paid by Tenant upon substantial completion of the Tenant Improvements; provided,
however, that if such additional cost is attributable to Landlord Delays, then
such additional cost shall be paid by Landlord.

          (e) If, after the Tenant Improvement Plans and the Final Pricing have
been approved, Tenant shall require any changes or substitutions to the Tenant
Improvement Plans, one-half (1/2) of any additional costs therefor, including
architectural and space planning fees, which are in excess of the Tenant
Improvement Allowance plus Tenant's Contribution shall be paid by Tenant to
Landlord within thirty (30) days after Landlord has provided Tenant with an
itemized invoice for such additional costs, and the balance shall be paid by
Tenant upon substantial completion of the Tenant Improvements.


                                   EXHIBIT B
                                  -----------
                                  Page 5 of 8
<PAGE>
 
          (f) For purposes of this Work Letter, a "Landlord Delay" shall mean
any delay in the substantial completion of the Tenant Improvements caused by any
act or omission by Landlord, its agents or contractors, including, without
limitation, any delay (i) attributable to changes in or additions to the Base
Building Plans, the Tenant Improvement Plans and/or the Tenant Improvements
after the same have been approved by Landlord and Tenant, and (ii) attributable
to the failure of Landlord to pay when due, any amounts required to be paid by
Landlord in connection with completion of the Base Building and the Tenant
Improvements pursuant to the Lease or this Work Letter except to the extent that
such failure is due to Tenant's failure to pay any additional Tenant Improvement
Costs as required under paragraph 7(d) or 7(e) of this Work Letter.

     8.  COMPLETION AND RENTAL COMMENCEMENT DATE

          (a) The commencement of the term of this Lease and Tenant's obligation
for the payment of rental under the Lease shall not commence until substantial
completion of construction of the Base Building and the Tenant Improvements.
For purposes of the Lease and this Work Letter, "substantial completion" of the
Tenant Improvements shall mean (i) the Base Building is complete and in
compliance with all Applicable Laws and all of the Base Building systems are
operational to the extent necessary to service the Premises; (ii) Landlord has
sufficiently completed all the work required to be performed by Landlord in
accordance with this Work Letter (except punch-list items which Landlord shall
thereafter promptly complete as provided in paragraph 9 below) to enable Tenant
to conduct its business operations (assuming installation by Tenant of all
cabling systems, equipment, fixtures, furnishings, and other personal property
necessary to conduct its business operations); (iii) Landlord has obtained a
certificate of occupancy, or its equivalent, for the Building (except to the
extent receipt of such certificate of occupancy, or its equivalent, is delayed
by any Tenant Delay); (iv) Tenant has been provided with the parking spaces and
parking privileges to which it is entitled under the Lease; (v) Tenant has been
delivered reasonable access to the Premises sufficient to allow Tenant to
install its freestanding work stations, fixtures, furniture, equipment, and
telecommunication and computer cabling systems; and (vi) Tenant has received a
non-disturbance agreement in form reasonably acceptable to Tenant signed by
Landlord and each ground lessor, mortgagee or deed of trust holder which is of
record prior to the Commencement Date of this Lease, the receipt of which shall
be a condition to this Lease.

          (b) However, if there shall be a delay in substantial completion of
the Base Building and/or the Tenant Improvements as a result of any act or
omission of Tenant, its agents or contractors, including, without limitation,
any of the following (each, a "Tenant Delay"):  (i)  Tenant's failure to approve
any item or perform any other obligation in accordance with and by the date
specified in the Work Schedule; (ii) Tenant's request for any materials,
finishes or installations which are not readily available, if Landlord notifies
Tenant prior to final approval of the Tenant Improvement Plans that use of such
materials, finishes or installations will negatively impact the completion
schedule (including an estimate of the anticipated delays associated with such
materials, finishes or installations) and Tenant nevertheless elects to use such
materials, finishes or installations; (iii) Tenant's changes in the Tenant
Improvement Plans after their approval by Tenant; (iv) rebidding of any
subtrades at Tenant's request; or (v) interference with Landlord's work caused


                                   EXHIBIT B
                                  -----------
                                  Page 6 of 8
<PAGE>
 
by Tenant or by Tenant's contractors or subcontractors if Tenant does not cease
such interference within two (2) business days after Landlord notifies Tenant of
the existence of such interference; then the commencement of the term of this
Lease and the rental commencement date shall be accelerated by the number of
days of such delay.

     9.  PUNCHLIST

          Upon substantial completion of the Tenant Improvements, or as soon
thereafter as reasonably practicable, Landlord, Tenant and Tenant's space
planner shall inspect the Premises and the Tenant Improvements and develop a
punch-list of those minor corrections of construction or decoration details and
minor mechanical adjustments that are required to cause any applicable portion
of the Tenant Improvements to conform to the Tenant Improvement Plans.  Upon
completion of such punch-list, Landlord shall promptly commence and complete
correction of such punch-list items in a manner that minimizes interference with
Tenant's business, but in no event later than thirty (30) days after submission
of such punch-list items to Landlord, subject to reasonable availability of
necessary materials.

     10.  RISK OF LOSS

          Landlord shall bear the risk of loss for all materials, work,
installations, and decorations brought onto or installed in the Premises or the
Building by Landlord or Landlord's agents, employees or contractors in
connection with the construction of the Tenant Improvements and/or the Base
Building prior to the Commencement Date, and neither Tenant nor Tenant's agents
or employees or any party acting on behalf of Tenant shall be liable for any
damage, loss or destruction thereof.

     11.  CHANGE REQUESTS

          Any request by Tenant for a change in the Tenant Improvements after
final approval of the Tenant Improvement Plans by Landlord and Tenant (a "Change
Request") shall be presented to Landlord in writing and shall be accompanied by
all information necessary to clearly identify and explain the proposed change.
As soon as practicable after receipt of such Change Request, Landlord shall
notify Tenant in writing of the estimated cost of such Change Request as well as
the estimated increase in construction time caused by the Change Request, if
any.  Tenant shall approve such estimates in writing within two (2) business
days after receipt of Landlord's notice.  Upon receipt of such written approval,
Landlord shall be authorized to cause the General Contractor to proceed with
implementation of the Change Request.  If Tenant disputes such estimates, or
fails to approve in writing such estimates within such two (2) business day
period, Landlord shall not be required to proceed with such Change Request, and
all costs incurred by Landlord or the General Contractor in preparing such
estimates shall be included in the cost of the Tenant Improvements, which cost
shall be paid by Tenant.  If Landlord is instructed by Tenant to proceed with a
Change Request prior to determination of the increased cost or increased
construction time resulting from such Change Request and without approval of
such increase by Tenant, the amount thereof shall be determined by Landlord upon
completion of the Tenant Improvements, subject only to Landlord furnishing to


                                   EXHIBIT B
                                  -----------
                                  Page 7 of 8
<PAGE>
 
Tenant appropriate back-up information from the General Contractor concerning
the increased costs and increased construction time, if any.

     In witness whereof, this Work Letter Agreement is executed as of the date
first written above.

LANDLORD:                                   ADDRESS:

Patrician Associates, Inc., a California    Patrician Associates, Inc.
corporation                                 c/o Parkway Properties, Inc.,
                                            7011 Koll Center,  Suite 210
By:_________________________________        Pleasanton, California  94566
Its:________________________________

By:_________________________________
Its:________________________________


TENANT:                                     ADDRESS:

Documentum, Inc., a                         Documentum, Inc.
California corporation                      5671 Gibraltar Drive
                                            Pleasanton, CA 94588-8547
By:_________________________________
Its:________________________________

By:_________________________________
Its:________________________________


                                   EXHIBIT B
                                  -----------
                                  Page 8 of 8
<PAGE>
 
                      STANDARDS FOR UTILITIES AND SERVICES
                      ------------------------------------

          The following Standards for Utilities and Services are in effect.
Landlord reserves the right to adopt nondiscriminatory modifications and
additions hereto:

          Landlord shall:

          (a) On Monday through Friday, except holidays, from 7 A.M. to 6 P.M.
(and other times for a reasonable additional charge to be fixed by Landlord as
provided in paragraph (b) below), ventilate the Premises and furnish air
conditioning or heating on such days and hours, when in the judgment of Landlord
it may be required for the comfortable occupancy of the Premises.  The air
conditioning system achieves maximum cooling when the window coverings are
closed.  Landlord shall not be responsible for room temperatures if Tenant does
not keep all window coverings in the Premises closed whenever the system is in
operation.  Tenant agrees to cooperate fully at all times with Landlord, and to
abide by all regulations and requirements which Landlord may reasonably
prescribe for the proper function and protection of said air conditioning
system.  Tenant agrees not to connect any apparatus, device, conduit or pipe to
the Building chilled and hot water air conditioning supply lines.  Tenant
further agrees that neither Tenant nor its servants, employees, agents,
visitors, licensees or contractors shall at any time enter mechanical
installations or facilities of the Building or adjust, tamper with, touch or
otherwise in any manner affect said installations or facilities.  The cost of
maintenance and service calls to adjust and regulate the air conditioning system
shall be charged to Tenant if the need for maintenance work results from
Tenant's failure to comply with its obligations under this section, including
keeping window coverings closed as needed.  Such work shall be charged at hourly
rates equal to Landlord's actual cost.

          (b) Landlord shall furnish to Tenant after-hours heating and air
conditioning at the actual cost for such after-hours use including a reasonable
estimate of maintenance expenses attributable to such after-hours use.  No other
fees or mark-ups will be charged by Landlord for Tenant's after-hours HVAC use.
Landlord shall bill Tenant monthly for such after-hours usage and Tenant shall
pay such charges to Landlord, as additional rent, within 20 days after receipt
of Landlord's statement of such charges.

          (c) Landlord shall furnish to the Premises electric current sufficient
for normal office use.  Tenant shall be entitled to use up to four (4) watts per
rentable square foot for connected electrical power to the Premises, exclusive
of ceiling lights and electricity for operation of the HVAC system.  Any
reasonable costs for the installation and operation of any additional HVAC
equipment which may be required due to electrical usage in excess of three (3)
watts per rentable square foot of connected electrical power to the Premises,
including maintenance costs and utility charges, shall be paid by Tenant.   If a
separate meter is not installed at Tenant's cost, such excess cost will be
established by an estimate agreed upon by Landlord and Tenant, and if the
parties fail to agree, as established by an independent licensed engineer.  Said
estimates to be reviewed and adjusted quarterly.  Tenant agrees not to use any
apparatus or device in, or upon, or about the Premises which may in any way
increase the amount of such services usually furnished or supplied to said
Premises, and Tenant further agrees not to connect any apparatus or device with
wires, 


                                   EXHIBIT B
                                  -----------
                                  Page 2 of 3
<PAGE>
 
conduits or pipes, or other means by which such services are supplied, for the
purpose of using additional or unusual amounts of such services without written
consent of Landlord, which shall not be unreasonably withheld. Should Tenant use
the same to excess, the refusal on the part of Tenant to pay within ten (10)
days after demand of Landlord the amount established by Landlord for such excess
charge shall constitute a breach of the obligation to pay rent under this Lease
and shall entitle Landlord to the rights therein granted for such breach. At all
times Tenant's use of electric current shall never exceed the capacity of the
feeders to the Building or the risers or wiring installation and Tenant shall
not install or use or permit the installation or use of any computer, larger
than personal computer, or electronic data processing equipment in the Premises,
without the prior written consent of Landlord, which shall not be unreasonably
withheld.

          (d) Water will be available in public areas for drinking and lavatory
purposes only, but if Tenant requires, uses or consumes water for any purposes
in addition to ordinary drinking and lavatory purposes of which fact Tenant
constitutes Landlord to be the sole judge, in its reasonable opinion, Landlord
may install a water meter and thereby measure Tenant's water consumption for all
purposes.  Tenant shall pay Landlord for the cost of the meter and the cost of
the installation thereof and throughout the duration of Tenant's occupancy,
Tenant shall keep said meter and installation equipment in good working order
and repair at Tenant's own cost and expense, in default of which Landlord may
cause such meter and equipment to be replaced or repaired and collect the cost
thereof from Tenant.  Tenant agrees to pay for water consumed, as shown on said
meter, as and when bills are rendered, and on default in making such payment,
Landlord may pay such charges and collect the same from Tenant.  Any such costs
or expenses incurred, or payments made by Landlord for any of the reasons or
purposes hereinabove stated shall be deemed to be additional rent payable by
Tenant and collectible by Landlord as such.

          (e) Provide janitor service to the Premises, provided the same are
kept reasonably in order by Tenant, and if to be kept clean by Tenant, no one
other than persons approved by Landlord shall be permitted to enter the Premises
for such purposes.  If the Premises are not used exclusively as offices
(including Tenant's climate-controlled room), they shall be kept clean and in
order by Tenant, at Tenant's expense, and to the satisfaction of Landlord, and
by persons approved by Landlord.  Tenant shall pay to Landlord the cost of
removal of any of Tenant's refuse and rubbish, to the extent that the same
exceeds the refuse and rubbish usually attendant upon the use of the Premises as
offices.

          (f) Landlord reserves the right to stop service of the elevator,
plumbing, ventilation, air conditioning and electric systems, when necessary, by
reason of accident or emergency or for repairs, alterations or improvements
which, in the good faith judgment of Landlord, are necessary, until said
repairs, alterations or improvements shall have been completed.  Landlord shall
provide Tenant with such prior notice of any intended stoppage in service as is
reasonable under the circumstances.  Landlord shall have no responsibility or
liability for failure to supply elevator facilities, plumbing, ventilating, air
conditioning or electric service, when prevented from so doing by strike or
accident or by any cause beyond Landlord's reasonable control, or by laws,
rules, orders, ordinances, directions, regulations or requirements of any
federal, state, county or municipal authority or  inability by exercise of
reasonable diligence by Landlord to obtain gas, oil or other suitable fuel.  It
is expressly understood and agreed that any covenants on Landlord's part 


                                   EXHIBIT B
                                  -----------
                                  Page 3 of 3
<PAGE>
 
to furnish any service pursuant to any of the terms, covenants, conditions,
provisions or agreements of this Lease, or to perform any act or thing for the
benefit of Tenant, shall not be deemed breached if Landlord is unable to furnish
or perform the same by virtue of a strike or labor trouble or any other cause
whatsoever beyond Landlord's control.


                                   EXHIBIT B
                                  -----------
                                  Page 4 of 3
<PAGE>
 
                             RULES AND REGULATIONS
                             ---------------------
                             Sycamore Plaza I & II

     1.  Except as specifically provided in the Lease to which these Rules and
Regulations are attached, no sign, placard, picture, advertisement, name or
notice shall be installed or displayed on any part of the outside or inside of
the Building without the prior written consent of Landlord, which shall not be
unreasonably withheld  Landlord shall have the right to remove, at Tenant's
expense and without notice, any sign installed or displayed in violation of this
rule.

     2.  If Landlord reasonably objects in writing to any curtains, blinds,
shades, screens or hanging plants or other similar objects attached to or used
in connection with any window or door of the Premises, or placed on any
windowsill, which is visible from the exterior of the Premises, Tenant shall
immediately discontinue such use.  Tenant shall not place anything against or
near glass partitions or doors or windows which may appear unsightly from
outside the Premises.

     3.  Tenant shall not obstruct any sidewalks, halls, passages, exits,
entrances, elevators, escalators, or stairways of the Project.  The halls,
passages, exits, entrances, elevators, and stairways are not open to the general
public, but are open, subject to reasonable regulation, to Tenant's business
invitees.  Landlord shall in all cases retain the right to control and prevent
access thereto of all persons whose presence in the reasonable judgment of
Landlord would be prejudicial to the safety, character and reputation of the
Project; provided that nothing herein contained shall be construed to prevent
such access to persons with whom any tenant normally deals in the ordinary
course of its business, unless such persons are engaged in illegal or unlawful
activities.  No tenant and no employee or invitee of any tenant shall go upon
the roof of any building of the Project.

     4.  The directory of the building will be provided exclusively for the
display of the name and location of tenants only, and Landlord reserves the
right to exclude any other names therefrom.

     5.

     6.  Landlord will furnish Tenant, free of charge, with two keys to each
door lock in the Premises.  Landlord may make a reasonable charge for any
additional keys.  Tenant shall not alter any lock or install a new additional
lock or bolt on any door of its Premises.  Tenant, upon the termination of its
tenancy, shall deliver to Landlord the keys of all doors which have been
furnished to Tenant, and in the event of loss of any keys so furnished, shall
pay Landlord therefor.

     7.  If Tenant requires telegraphic, telephonic, burglar alarm or similar
services, it shall first obtain, and comply with, Landlord's written
instructions, if any, in their installation.

     8.  Tenant shall not place a load upon any floor of the Premises which
exceeds the load per square foot which such floor was designed to carry and
which is allowed by law.  Landlord shall have the right to prescribe the weight
of all equipment or other machinery or apparatus brought into the Project.
Heavy objects shall, if considered necessary by Landlord, stand on such
platforms as determined by Landlord to be reasonably necessary to properly
distribute the weight, which 


                                   EXHIBIT D
                                  -----------
                                  Page 1 of 5

<PAGE>
 
platforms shall be provided at Tenant's expense. Business machines and
mechanical equipment belonging to Tenant, which cause noise or vibration that
may be transmitted to the structure of the Premises to such a degree to be
objectionable to Landlord, shall be placed and maintained by Tenant, at Tenant's
expense, on vibration eliminators or other devices sufficient to eliminate noise
or vibration. The moving companies employed to move such equipment in or out of
the Premises must be reasonably acceptable to Landlord. Landlord will not be
responsible for loss of, or damage to, any such equipment or other property from
any cause, and all damage done to the Premises, by maintaining or moving such
equipment or other property shall be repaired at the expense of Tenant.

     9.  Tenant shall not use or keep in the Premises any kerosene, gasoline or
inflammable or combustible fluid or material other than those limited quantities
necessary for the operation or maintenance of office equipment.  Tenant shall
not use or permit to be used in the Premises any foul or noxious gas or
substance, or permit or allow the Premises to be occupied or used in a manner
injurious to Landlord or other occupants of the Project by reason of noise,
odors or vibrations, nor shall Tenant bring into or keep in or about the
Premises any birds or animals.

     10.  Tenant shall not use any method of heating or air-conditioning other
than that supplied by Landlord.

     11.  Tenant shall not waste electricity, water or air-conditioning and
agrees to cooperate fully with Landlord to assure the most effective operation
of the Premises' heating and air-conditioning and to comply with any
governmental energy-saving rules, laws or regulations of which Tenant has actual
notice.  Tenant shall keep corridor doors closed, and shall close window
coverings at the end of each business day.

     12.  Landlord reserves the right, exercisable with notice but without
liability to Tenant, to change the name and street address of the Premises.

     13.  Landlord reserves the right to exclude from the Project between the
hours of 6 p.m. and 7 a.m. the following day, or such other hours as may be
established from time to time by Landlord, and on Sundays and legal holidays,
any person unless that person is known to the person or employee in charge of
the Project and has a pass or is properly identified.  Tenant shall be
responsible for all persons for whom it requests passes and shall be liable to
Landlord for all acts of such persons.  Landlord shall not be liable for damages
for any error with regard to the admission to or exclusion from the Project of
any person.  Landlord reserves the right to prevent access to the Project in
case of invasion, mob, riot, public excitement or other commotion by closing the
doors or by other appropriate action.

     14.  Tenant shall close and lock the doors of its Premises and entirely
shut off all water faucets or other water apparatus, and electricity, gas or air
outlets before tenant and its employees leave the Premises.

     15.  Tenant shall not obtain for use on the Premises ice, drinking water,
food beverages, towel or other similar services upon the Premises, except at
such hours and under such regulations 


                                   EXHIBIT D
                                  -----------
                                  Page 2 of 5
<PAGE>
 
as may be fixed by Landlord. The foregoing shall not, however, prevent Tenant
from installing and operating a refrigerator, coffee maker and/or microwave oven
in any kitchen or lunchroom in the Premises.

     16.  The toilet rooms, toilets, urinals, wash bowls and other apparatus
shall not be used for any purpose other than that for which they were
constructed and no foreign substance of any kind whatsoever shall be thrown
therein.  The expense of any breakage, stoppage of damage resulting from the
violation of this rule shall be borne by the tenant who, or whose employees or
invitees, shall have caused it.

     17.  Tenant shall not sell, or permit the sale at retail, of newspapers,
magazines, periodicals, theater tickets or any other goods or merchandise to the
general public in or on the Premises.  Tenant shall not make any room-to-room
solicitation of business from other tenants in the Project.  Tenant shall not
use the Premises for any business or activity other than that specifically
provided for in Tenant's Lease.

     18.  Tenant shall not install any radio or television antenna, loudspeaker
or other devices on the roof or exterior walls of the Premises.  Tenant shall
not interfere with radio or television broadcasting or reception from or in the
Project or elsewhere.

     19.  Tenant shall not mark, drive nails, screw or drill into the
partitions, woodwork or plaster or in any way deface the Premises or any part
thereof, except in accordance with the provisions of the Lease pertaining to
alterations.  Tenant shall not cut or bore holes for wires.  Tenant shall not
affix any floor covering to the floor of the Premises in any manner except as
reasonably approved by Landlord.  Tenant shall repair any damage resulting from
noncompliance with this rule.

     20.  Tenant shall not install, maintain or operate upon the Premises any
vending machines without the written consent of Landlord, which shall not be
unreasonably withheld.

     21.  Canvassing, soliciting and distributing of handbills or any other
written material, and peddling in the Project are prohibited, and Tenant shall
cooperate to prevent such activities.

     22.  Landlord reserves the right to exclude or expel from the Project any
person who, in Landlord's good faith judgment, is intoxicated or under the
influence of liquor or drugs or who is in violation of any of the Rules and
Regulations of the Project.

     23.  Tenant shall store all its trash and garbage within its Premises or in
other facilities provided by Landlord at the Premises.  Tenant shall not place
in any trash box or receptacle any material which cannot be disposed of in the
ordinary and customary manner of trash and garbage disposal.  All garbage and
refuse disposal shall be made in accordance with directions reasonably issued
from time to time by Landlord.

     24.  The Premises shall not be used for the storage of merchandise held for
sale to the general public, or for lodging or for manufacturing of any kind, nor
shall the Premises be used for 


                                   EXHIBIT D
                                  -----------
                                  Page 3 of 5
<PAGE>
 
any improper, immoral or objectionable purpose. No cooking shall be done or
permitted on the Premises without Landlord's consent, except that use by Tenant
of Underwriter's Laboratory approved equipment for brewing coffee, tea, hot
chocolate and similar beverages or use of microwave ovens for employee use shall
be permitted, provided that such equipment and use is in accordance with all
Applicable Laws.

     25.  Tenant shall not use in the Premises any hand truck except those
equipped with rubber tires and side guards or such other material-handling
equipment as Landlord may approve.  Tenant shall not bring any other vehicles of
any kind into the Premises.

     26.  Without the written consent of Landlord, Tenant shall not use the name
of the Project in connection with or in promoting or advertising the business of
Tenant except as Tenant's address.

     27.  Tenant shall comply with all safety, fire protection and evacuation
procedures and regulations established by Landlord or any governmental agency.

     28.  Tenant and its employees, guests and invitees shall not enter into the
waterways located in the Project. No object of any kind may be floated or
submerged in the waterways, and no foreign substance of any kind may be thrown
in the waterways. The expense of any breakage or damage to any mechanical
equipment related to the waterways resulting from violation of this rule or any
expense incurred restoring the waterways to their normal condition shall be
borne by the tenant who, or whose employees or invitees, shall have caused such
damage.

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

     30.  Tenant's requirements will be attended to only upon written request to
the Project management office by an authorized individual.  Employees of
Landlord shall not perform any work or do anything outside of their regular
duties unless under special instructions from Landlord, and no employee of
Landlord will admit any person (Tenant or otherwise) to any office without
specific instructions from Landlord.

     31.  Landlord may waive any one or more of these Rules and Regulations for
the benefit of Tenant or any other tenant, but no such waiver by Landlord shall
be construed as a waiver of such Rules and Regulations in favor of Tenant or any
other tenant, nor prevent Landlord from thereafter enforcing any such Rules and
Regulations against any or all of the tenants of the Project.

     32.  These Rules and Regulations are in addition to, and shall not be
construed to in any way modify or amend, in whole or in part, the terms,
covenants, agreements and conditions of Tenant's lease of its Premises in the
Project.

     33.  Landlord reserves the right to make such other and reasonable Rules
and Regulations as, in its judgment, may from time to time be needed for safety
and security, for care and cleanliness 


                                   EXHIBIT D
                                  -----------
                                  Page 4 of 5
<PAGE>
 
of the Project and for the preservation of good order therein, provided that any
such Rules and Regulations do not materially impair Tenant's use of or access to
the Premises. Tenant agrees to abide by all such Rules and Regulations
hereinabove stated and any additional rules and regulations which are adopted.
In particular, tenant shall comply at all times with the City of Pleasanton's
Transportation Systems Management Ordinance (TSM Ordinance, Chapter 17.24,
Pleasanton Municipal Code), as said Ordinance may be amended from time to time."

     34.  Tenant shall be responsible for the observance of all of the foregoing
rules by Tenant's employees, agents, clients, customers, invitees and guests.


                                   EXHIBIT D
                                  -----------
                                  Page 5 of 5
<PAGE>
 
                         PARKING RULES AND REGULATIONS
                         -----------------------------

The following rules and regulations shall govern use of the parking facilities
which are appurtenant to the Building.

     1.  All claimed damage or loss must be reported and itemized in writing
delivered to the Landlord within ten business days after any claimed damage or
loss occurs or as promptly as practicable.  Court actions by Tenant for any
claim must be filed in the court of jurisdiction where a claimed loss occurred.
Landlord is not responsible for damage by water, fire, or defective brakes, or
parts, or for the act of omissions of others, or for articles left in the car.
Landlord is not responsible for loss of use.

     2.  Tenant shall not park or permit the parking of any vehicle under its
control in any parking areas designated by Landlord as areas for parking by
visitors to the Building.  Tenant shall not leave vehicles in the parking areas
overnight (other than company-owned automobiles which may be parked overnight in
a designated location agreed to by Landlord and Tenant) nor park any vehicles in
the parking areas other than automobiles, motorcycles, motor driven or non-motor
driven bicycles or four-wheeled trucks.

     3.  Parking stickers or any other device or form of identification supplied
by Landlord as a condition of use of the Parking Facilities shall remain the
property of Landlord.  Such parking identification device must be displayed as
requested and may not be mutilated in any manner.  The serial number of the
parking identification device may not be obliterated.  Devices are not
transferable and any device in the possession of an unauthorized holder will be
void.

     4.  No extended term storage of vehicles shall be permitted.  Overnight
parking of company-owned automobiles only shall be permitted in a designated
location agreed to by Landlord and Tenant.

     5.  Vehicles must be parked entirely within the painted stall lines of a
single parking stall.

     6.  All directional signs and arrows must be observed.

     7.  The speed limit within all parking areas shall be 5 miles per hour.

     8.  Parking is prohibited:

          (a) in areas not striped for parking;

          (b) in aisles;

          (c) where "no parking" signs are posed;

          (d) on ramps;


                                   EXHIBIT E
                                  -----------
                                  Page 1 of 2
<PAGE>
 
          (e)  in cross hatched areas; and

     (f)  in such other areas as may be designated by Landlord or Landlord's
Parking Operator.

     9.   Every parker is required to park and lock his own vehicle.  All
responsibility for damage to vehicles is assumed by the parker.

     10.  Loss or theft of parking identification devices from automobiles must
be reported immediately, and a lost or stolen report must be filed by the
customer at that time.  Landlord has the right to exclude any car from the
parking facilities that does not have an identification.

     11.  Any parking identification devices reported lost or stolen found on
any unauthorized car will be confiscated and the illegal holder will be subject
to prosecution.

     12.  Any lost or stolen parking identification devices which are found must
be reported immediately to avoid confusion.

     13.  Washing, waxing, cleaning or servicing of any vehicle in any area not
specifically reserved for such purpose is prohibited.

     14.  Landlord reserves the right to refuse the sale of monthly stickers or
other parking identification devices to any tenant or person and/or his agents
or representatives who willfully refuse to comply with these Rules and
Regulations and all unposted City, State or Federal ordinances, laws or
agreements.

     15.  Landlord reserves the right to modify and/or adopt such other
reasonable and non-discriminatory rules and regulations for the parking
facilities as it deems necessary for the operation of the parking facilities.
Landlord may refuse to permit any person who violates these rules to park in the
parking facilities, and any violation of the rules shall subject the car to
removal.


                                   EXHIBIT E
                                  -----------
                                  Page 2 of 2
<PAGE>
 




                             BERNAL CORPORATE PARK
                             ---------------------

                               SYCAMORE PLAZA II
                               -----------------



                                 OFFICE LEASE

                                    BETWEEN

                          PATRICIAN ASSOCIATES, INC.

                                 ("LANDLORD")


                                      AND


                               DOCUMENTUM, INC.

                                  ("TENANT")
<PAGE>
 
                               TABLE OF CONTENTS
                               -----------------
<TABLE>
<CAPTION>

ARTICLE                                                        PAGE
-------                                                        ----

<S>                                                             <C>
1  TERM......................................................... 2

2  POSSESSION................................................... 2

3  BASIC RENT................................................... 4

4  RENTAL ADJUSTMENT............................................ 5

5  SECURITY DEPOSIT............................................. 8

6  USE.......................................................... 10

7  NOTICES...................................................... 12

8  BROKERS...................................................... 12

9  HOLDING OVER................................................. 12

10 TAXES ON TENANT'S PROPERTY................................... 12

11 CONDITION OF PREMISES........................................ 13

12 ALTERATIONS.................................................. 14

13 REPAIRS...................................................... 15

14 LIENS........................................................ 15

15 ENTRY BY LANDLORD............................................ 16

16 UTILITIES AND SERVICES....................................... 16

17 BANKRUPTCY................................................... 17

18 INDEMNIFICATION.............................................. 18

19 DAMAGE TO TENANT'S PROPERTY.................................. 18

20 INSURANCE.................................................... 19
</TABLE>

                                       i
<PAGE>
 
<TABLE>
<S>                                                              <C>
21 DAMAGE OR DESTRUCTION........................................ 20

22 EMINENT DOMAIN............................................... 22

23 DEFAULTS AND REMEDIES........................................ 23

24 ASSIGNMENT AND SUBLETTING.................................... 25

25 SUBORDINATION................................................ 27

26 ESTOPPEL CERTIFICATE......................................... 28

27 SIGNAGE...................................................... 29

28 RULES AND REGULATIONS........................................ 29

29 CONFLICT OF LAWS............................................. 29

30 SUCCESSORS AND ASSIGNS....................................... 30

31 SURRENDER OF PREMISES........................................ 30

32 ATTORNEYS' FEES.............................................. 30

33 PERFORMANCE BY TENANT........................................ 30

34 MORTGAGEE PROTECTION......................................... 31

35 DEFINITION OF LANDLORD....................................... 31

36 WAIVER....................................................... 31

37 IDENTIFICATION OF TENANT..................................... 32

38 PARKING...................................................... 32

39 TERMS AND HEADINGS........................................... 32

40 EXAMINATION OF LEASE......................................... 33

41 TIME......................................................... 33

42 PRIOR AGREEMENT: AMENDMENTS.................................. 33
</TABLE>

                                      ii
<PAGE>
 
<TABLE>
<S>                                                              <C>
43 SEPARABILITY................................................. 33

44 RECORDING.................................................... 33

45 CONSENTS..................................................... 33

46 LIMITATION ON LIABILITY...................................... 34

47 RIDERS....................................................... 34

48 EXHIBITS..................................................... 34

49 MODIFICATION FOR LENDER...................................... 35

50 WAIVER OF LIEN RIGHTS........................................ 35

51 EXPANSION RIGHTS............................................. 35

52 OPTION TO EXTEND............................................. 36

53 LANDLORD'S CONDITION......................................... 37
</TABLE>


                                LIST OF EXHIBITS
                                ----------------



EXHIBIT A-1             The Premises

EXHIBIT A-2             The Project

EXHIBIT B               Work Letter Agreement

EXHIBIT C               Standards for Utilities and Services

EXHIBIT D               Rules and Regulations

EXHIBIT E               Parking Rules and Regulations

EXHIBIT F               Tenant's Letter of Credit

EXHIBIT G               Subordination, Non-Disturbance and Attornment Agreement

                                      iii
<PAGE>
 
                             BERNAL CORPORATE PARK
                              SYCAMORE  PLAZA II


          THIS LEASE is made as of June 22, 1998 by and between PATRICIAN
ASSOCIATES, Inc., a California corporation ("Landlord"), and DOCUMENTUM, INC., a
California corporation ("Tenant").

          Landlord hereby leases to Tenant and Tenant hereby leases from
Landlord the Premises (the "Premises") outlined on the floor plan attached
hereto and marked EXHIBIT A-1, the Premises being agreed, for the purposes of
                  -----------                                                
this Lease, to have an area of approximately sixty-three thousand six hundred
thirty-two (63,632) rentable square feet and being situated on the third and
fourth floors of that certain four-story office building to be constructed at
6701 Koll Center Parkway, Pleasanton, California 94566 (the "Building").  The
Building shall contain approximately one hundred twenty-two thousand four
hundred forty-two (122,442) rentable square feet of space.  As an appurtenant
right to Tenant's leasing of the Premises, Landlord hereby grants to Tenant, for
the benefit of Tenant and its employees, suppliers, shippers, customers and
invitees, during the term of this Lease, the non-exclusive right to use, in
common with others entitled to such use, (i) those portions of the common areas
within the Project and within Bernal Corporate Park which are improved from time
to time for use as parking areas, driveways, sidewalks, landscaped areas, or for
other common purposes including, for example the fitness center and conference
room currently available to the tenants of Bernal Corporate Park, and (ii) all
easements, licenses and similar rights and privileges relating to or appurtenant
to the Building or the Project and created or existing from time to time under
any written agreements.  For purposes of this Lease, all references herein to
the "Project" shall mean the Building plus the parcel of land upon which the
Building is constructed, including all parking facilities, driveways, sidewalks,
plazas, and landscaped areas appurtenant to the Building and within such parcel
of land, as more particularly shown on the site plan attached as EXHIBIT A-2.
                                                                 -----------  
The Premises shall consist initially of approximately thirty-one thousand seven
hundred eighty-three (31,783) rentable square feet, located on the fourth floor
of the Building ("Suite 400"), and upon substantial completion of the Tenant
Improvements for Suite 300, the Premises shall be further expanded to  include
an additional thirty-one thousand eight hundred forty-nine (31,849) rentable
square feet on the third floor of the Building as shown on EXHIBIT A-1 ("Suite
                                                           -----------        
300").  Landlord and Tenant have also entered into a lease of even date herewith
for the building to be constructed at 6801 Koll Center Parkway, Pleasanton,
California, consisting of approximately one hundred twenty-two thousand four
hundred forty-two (122,442) rentable square feet ("Sycamore Plaza I Lease").
The Premises shall be measured in accordance with the Building Managers and
Owners Association Standard ANSI-Z65.1 (1996) to determine the rentable and
usable area of the Premises.  Tenant shall have the right to verify the
measurement of the Premises, at Tenant's expense, prior to the Commencement Date
using the foregoing BOMA standards.

          The parties hereto agree that said letting and hiring is upon and
subject to the terms, covenants and conditions herein set forth.  Landlord and
Tenant each covenant, as a material part of the consideration for this Lease to
keep and perform each and all of said terms, covenants and conditions for which
such party is liable hereunder and that this Lease is made upon the condition of
such performance.
<PAGE>
 
          Prior to the commencing of the term of this Lease the Premises shall
be improved by the Tenant Improvements described in the Work Letter marked
                                                                          
EXHIBIT B attached hereto.
---------                 

                                   ARTICLE 1
                                   ---------
                                     TERM
                                     ----

          (a) The term of this Lease shall be for approximately seventy-seven
(77) months, unless sooner terminated as hereinafter provided, commencing upon
the date ("Commencement Date") which is the earlier of:

              (i)  Completion of the Base Building and substantial completion
(as defined in the Work Letter) of the Tenant Improvements to Suite 400 of the
Premises described in the Work Letter (subject to the provisions of Paragraph 8
of the Work Letter) and the tender of possession of those Premises to Tenant,
subject only to completion of "punch- list" items which do not in the aggregate
materially interfere with Tenant's ability to occupy the Premises for the use
contemplated herein, or

              (ii) The date that Tenant opened for business in Suite 400 of
the Premises,

and ending on the date which is seven (7) years from the commencement date of
the Sycamore Plaza I Lease, unless such term shall be sooner terminated as
hereinafter provided.  As soon as the Commencement Date is determined, the
parties shall execute a written acknowledgment setting forth the precise
commencement and termination dates of this Lease.  Failure to enter into such an
amendment, however, shall not affect Tenant's liability hereunder.  Reference in
this Lease to a "Lease Year" shall mean each successive twelve month period
commencing with the Commencement Date.

Landlord and Tenant anticipate that the Commencement Date will occur on or about
January 1, 2000 and that substantial completion of the Tenant Improvements for
Suite 300 will occur on or about April 1, 2000.

          (b) Tenant shall be permitted to access Suite 400 of the Premises
approximately two (2) weeks prior to the Commencement Date and Suite 300 of the
Premises approximately two (2) weeks prior to the anticipated completion of the
Tenant Improvements to Suite 300 for the purpose of taking preparatory measures
in contemplation of its occupancy, including but not limited to, installing
fixtures and furniture, computer equipment, telecommunications equipment, and
other personal property, subject to all of the terms and conditions of this
Lease, except the obligation to pay Basic Rent or Direct Expenses, provided that
Tenant's access does not unreasonably interfere with completion of the Tenant
Improvements.

                                   ARTICLE 2
                                   ---------
                                  POSSESSION
                                  ----------

          (a) Landlord shall use diligent efforts to complete the Base Building
and the Tenant Improvements promptly.  Tenant agrees, however, that if Landlord
is unable to deliver 
<PAGE>
 
possession of Suite 400 to Tenant on or before January 1, 2000 or if Landlord is
unable to deliver possession of Suite 300 to Tenant by April 1, 2000, subject to
the provisions of paragraphs 2(b) and 2(c), this Lease shall not be void or
voidable, nor shall Landlord be liable to Tenant for any loss or damage
resulting therefrom, but in such event the term of this Lease shall not commence
until Landlord tenders possession of Suite 400 of the Premises to Tenant with
the Tenant Improvements substantially completed. If Landlord completes
construction of such Tenant Improvements and Base Building, including access
thereto, prior to the date scheduled in the Work Letter, Landlord shall deliver
possession of Suite 400 of the Premises to Tenant upon such completion and the
term of this Lease shall commence five (5) days after Landlord has notified
Tenant of such completion.

          (b) If the Commencement Date has not occurred by February 1, 2000 for
any reason other than Tenant Delays (as defined in the Work Letter) or delays
caused by Force Majeure (as defined herein), then Tenant shall be entitled to
one (1) day of free Basic Rent for each day of delay in substantial completion
that occurs from and after February 1, 2000 (as such date may be extended by
Tenant Delays and Force Majeure delays) until the earlier of the Commencement
Date or July 1, 2000; provided, however, that no more than sixty (60) days of
Force Majeure delays may accrue at any time between the date this Lease is fully
executed and July 1, 2000 before Tenant is entitled to begin accruing free Basic
Rent.  If, however, the Commencement Date has not occurred by July 1, 2000, but
Tenant has not elected to terminate this Lease as permitted in paragraph 2(c)
below, Tenant shall not be entitled to accrue any additional days of free Basic
Rent beyond July 1, 2000, regardless of when the Commencement Date actually
occurs.  If the completion of the Base Building and/or the Tenant Improvements
is delayed due to inclement weather, strikes or other labor disturbances,
material shortages, casualties, or other causes beyond Landlord's reasonable
control ("Force Majeure"), Landlord shall notify Tenant in writing within two
(2) business days after the occurrence thereof that an event of Force Majeure
has occurred and will delay the Commencement Date, and in such event the date
for substantial completion of the Base Building and the Tenant Improvements
shall be extended for the period of time reasonably attributable to the
occurrence of such Force Majeure.

          (c) If Landlord has not obtained a building permit for the base
building to be constructed at 6801 Koll Center Parkway by October 15, 1998,
Tenant may cancel this Lease by delivery of written notice to Landlord no later
than October 31, 1998.  Furthermore, if the Commencement Date has not occurred
by July 1, 2000 for any reason other than Tenant Delays, then Tenant may cancel
this Lease by delivery of written notice to Landlord no later than July  31,
2000.  Landlord shall have the right to cancel this Lease if the Commencement
Date has not occurred due to more than 365 days of delay caused by Force
Majeure.  In such event, Landlord may terminate this Lease by written notice to
Tenant within thirty (30) days after the occurrence of the 365th day of Force
Majeure delays.  Upon cancellation of this Lease by either party, Landlord shall
return to Tenant all sums previously deposited with Landlord by Tenant under
this Lease, and neither party shall have any further liability to the other
under this Lease.  If either party elects to cancel this Lease as permitted
herein, such cancellation and the return of all sums previously paid by Tenant
shall be in lieu of any free rent to which Tenant may be entitled under
paragraph 2(b), shall be Tenant's sole and exclusive remedy for Landlord's
inability to obtain the building permit for the building at 6801 Koll Center
Parkway by October 15, 1998 or to complete the Base Building and the Tenant
Improvements by July 1, 2000, as the case may be, and Landlord shall have no
liability to Tenant for any other damages or losses suffered or incurred by
Tenant as a result thereof.
<PAGE>
 
                                   ARTICLE 3
                                   ---------
                                  BASIC RENT
                                  ----------

          (a) Tenant agrees to pay Landlord Basic Rent for the Premises  as
follows:
<TABLE> 
<CAPTION> 
                       Months of Term         Basic Rent/Per Month
                       --------------         --------------------
<S>                    <C>                    <C> 
Suite 400              1 through 77*            $76,279.00/month

Suite 300              4 through 77*            $74,845.00/month
</TABLE> 

*  The number of months reflected in this schedule for the term of the Lease is
based upon an anticipated Commencement Date of January 1, 2000.  The term of the
Lease shall expire on the date which is seven (7) years from the commencement
date of the Sycamore Plaza I Lease and Basic Rent shall be paid in the foregoing
amounts through such date.  Similarly, the commencement of Basic Rent for Suite
300 is based upon an anticipated completion date of April 1, 2000 for the Tenant
Improvements to Suite 300.  Subject to the provisions of paragraph 8 of the Work
Letter Agreement, Basic Rent for Suite 300 shall commence on the date of
substantial completion of the Tenant Improvements for Suite 300.

The Basic Rent shall be paid monthly, in advance on the first (1st) day of each
calendar month during the term, commencing on the first (1st) month of the Lease
term and continuing on the first day of each month thereafter, except that the
first (1st) month's rent shall be paid on execution hereof.  If Tenant's
obligation to pay rent commences or ends on a day other than the first day of a
calendar month, then the rental for such period shall be prorated in the
proportion that the number of days this Lease is in effect during such period
bears to thirty.  In addition to the Basic Rent, Tenant agrees to pay as
additional rental the amount of rental adjustments and other charges required by
this Lease.  All rental shall be paid to Landlord, without prior demand and
without any deduction or offset, except as otherwise expressly provided herein,
in lawful money of the United States of America, at the address of Landlord
designated on the signature page of this Lease or to such other person or at
such other place as Landlord may from time to time designate in writing.

          (b) Late Charges.   In the event Tenant fails to pay any installment
              ------------                                                    
of rent when due or Tenant fails to make any other payment for which Tenant is
obligated under this Lease when due, and such failure continues for more than
three (3) business days after the date such rent or other payment is due, then
Tenant shall pay to Landlord a late charge equal to 5% of the amount due to
compensate Landlord for the extra costs incurred as a result of such late
payment; provided, however, that Landlord agrees to waive such late charge for
the first instance in any calendar year that any rent or other payment is not
paid within such three-day period.
<PAGE>
 
                                   ARTICLE 4
                                   ---------
                               RENTAL ADJUSTMENT
                               -----------------

          (a) For the purpose of this Article 4, the following terms are defined
as follows:

              (i)   Tenant's Percentage.   That portion of the Project occupied 
                    -------------------
by Tenant divided by the total rentable square footage of the Project.  Upon
completion of the working drawings for the Tenant Improvements to the Premises,
Landlord and Tenant shall execute a memorandum stating Tenant's Percentage as of
the Commencement Date and as of the date of completion of the Tenant
Improvements for Suite 300.

              (ii)  Direct Expenses Base.  The amount of the annual Direct 
                    --------------------
Expenses which Landlord has included in Basic Rent, which amount is Tenant's
Percentage of the actual Direct Expenses for the Project known as Sycamore Plaza
I for the third through fourteenth months of the term of the Sycamore Plaza I
Lease.

              (iii) Direct Expenses.   The term "Direct Expenses" shall
                    ---------------                                    
include:

                    (A) All real and personal property taxes and assessments
(excluding those assessments described in Paragraph 4(a)(iii)(E)) imposed by any
governmental authority or agency on the Project and the land on which the
Project is located (including a pro-rata portion of any taxes levied on any
common areas); any assessments levied in lieu of taxes; any non-progressive tax
on or measured by gross rentals received from the rental of space in the
Project; and any other costs levied or assessed by, or at the direction of, any
federal, state, or local government authority in connection with the use or
occupancy of the Project or the parking facilities serving the Project; any tax
on this transaction or any document to which Tenant is a party creating or
transferring an interest in the Project, and any expenses, including the
reasonable cost of attorneys or experts, reasonably incurred by Landlord in
seeking reduction by the taxing authority of the above-referenced taxes, less
tax refunds obtained as a result of an application for review thereof; but shall
not include any net income, franchise, capital stock, estate or inheritance
taxes. Tenant's obligation to pay any assessments included within real property
taxes and assessments shall be calculated on the basis of the amount due if
Landlord had allowed the assessment to go to bond and the same were paid over
the longest period available.

                    (B) Operating costs consisting of costs incurred by Landlord
in maintaining and operating the Project, exclusive of costs required to be
capitalized for federal income tax purposes, and including (without limiting the
generality of the foregoing) the following: costs of utilities, supplies and
insurance, cost of services of independent contractors, managers and other
suppliers, cost of compensation (including employment taxes and fringe benefits)
of all persons who perform regular and recurring duties connected with the
management, operation, maintenance, and repair of the Project, its equipment,
parking facilities and the common areas, including, without limitation,
engineers, janitors (unless Tenant has elected to provide janitorial service to
the Premises as permitted in paragraph 16(b)), foremen, floor waxers, window
washers, watchmen and gardeners, cost of maintaining, repairing and replacing
landscaping, sprinkler systems, concrete walkways, paved parking areas, signs,
and site lighting.
<PAGE>
 
                    (C) Amortization of such capital improvements as Landlord
may have installed for the purpose of reducing operating costs, but only to the
extent of the actual savings in operating costs realized as a result of such
capital improvement(s). The cost of such capital improvements, together with
interest at the maximum rate allowed by law, shall be amortized over such
reasonable period as Landlord shall determine, and only the monthly amortized
cost shall be included in Direct Expenses monthly.

                    (D) Any costs required by the CC&R's, as defined in Article
6, affecting the Project or by any corporation, committee or association formed
in connection therewith,

                    (E) Assessments.  Tenant acknowledges that the Project is 
                        -----------
subject to assessments levied to secure bonds sold by the City of Pleasanton
pursuant to Consolidated Reassessment District 1993-1. Such assessments shall be
Landlord's responsibility throughout the term of this Lease. Tenant hereby
consents to the formation of any other districts formed for maintenance,
utilities, landscaping, lighting, special service zones, fire district, water
district, road extensions, traffic mitigation, sports facilities or other
improvements in the Premises or Bernal Corporate Park and to the re-financing of
any assessment districts. Tenant hereby waives any right of notice and protest
in connection with the formation and continued existence of the assessment
districts; provided, however, that Tenant shall retain the right to contest the
amount of any new assessments levied against the Premises or the Project during
the term of this Lease. Tenant shall execute all documents, including, but not
limited to, petitions and formal waivers of notice and protest of formation,
evidencing such consent and waiver upon request of Landlord or the City of
Pleasanton.

              (iv)  Exclusions from Direct Expenses.  Direct Expenses shall not
                    -------------------------------                            
include any of the following: (A) depreciation and other non-cash items; (B)
costs of tenants' improvements; (C) capital items (except to the extent
expressly permitted under paragraph 4(a)(iii)(C)); (D) payments of principal and
interest on debt; (E) leasing commissions; (F) cost of any goods and services
(including utilities) for which any tenants or other occupants of the Project
separately reimburse Landlord; (G) costs incurred to perform or correct any
tenant improvement work; (H) costs of correcting defects in or inadequacy of the
initial design of the structure of the Building; (I) legal fees (except as
expressly provided for in paragraph 4(a)(iii)(A)); (J) amounts paid to
affiliates of Landlord (i.e., persons or entities controlled by, under common
control with, or which control, Landlord) for services to the Project, to the
extent that the costs of such services exceed competitive costs for such
services were they not rendered by an affiliate of Landlord; (K) expenses in
connection with services or other benefits provided to one of more tenants but
which are not generally available to other tenants of the Project; (L) wages of
any employee above the level of Building manager and chief engineer; (M) space
planning fees, architectural fees, engineering fees (other than those relating
to the general operation of the Project), marketing, advertising or any expense
incurred in connection with the development or leasing of the Project; (N) costs
associated with the operation of the business of the legal entity which
constitutes Landlord as the same is separate from the costs of operation of the
Project, including legal entity formation and internal entity accounting; (O)
any late fees or penalties or similar fees incurred by Landlord, except to the
extent attributable to Tenant's late payment of Basic Rent, Direct Expenses or
any other sums due under this Lease; (P) any debt losses, rent losses or
reserves for bad debt; (Q) any expenses incurred 
<PAGE>
 
for use of any public portions of the Project including, but not limited to,
shows and promotions; (R) the costs of installing an observatory, broadcasting
facility, luncheon club, athletic or recreational club, and the costs of
operating and maintaining any of the foregoing which are in excess of the costs
of services provided to other tenants of the Project generally; (S) costs of
adding any additional space to the Project after the original construction; (T)
costs of any repairs to the Project in accordance with the provisions of
Articles 21 (Damage and Destruction) and 22 (Eminent Domain) of this Lease; (U)
Landlord's incremental costs incurred by reasons of Landlord's breach of any
lease in the Project and any cost incurred by reason of the breach by other
tenants of the Project of such tenants' leases (to the extent recoverable from
such tenants); (V) unrecovered expenses incurred as a consequence of the grossly
negligent operation and maintenance of the Project by Landlord or Landlord's
employees; and (W) any fines, penalties, costs or expenses incurred in
connection with the investigation, removal, monitoring, clean-up or other
remediation of any contamination, or threatened contamination, by Toxic
Materials in, on or under the Premises or the Project.

          (b) Payment of Direct Expenses.
              -------------------------- 

              (i)   If Tenant's Percentage of the Direct Expenses paid or
incurred by Landlord for any calendar year of the term exceeds the Direct
Expenses Base, then Tenant shall pay such excess as additional rent. For each
calendar year, or portion thereof, Tenant shall pay Tenant's Percentage of
Landlord's estimate of the amount by which Direct Expenses for that year shall
exceed the Direct Expenses Base ("Landlord's Estimate"). This estimated amount
shall be divided into twelve equal monthly installments. Tenant shall pay to
Landlord, concurrently with the regular monthly rent payment next due following
the receipt of such statement, an amount equal to one monthly installment
multiplied by the number of months from January in the calendar year in which
said statement is submitted to the month of such payment, both months inclusive.
Subsequent installments shall be payable concurrently with the regular monthly
rent payments for the balance of that calendar year and shall continue until the
next calendar year's statement is rendered. If at any time during the term of
this Lease the Project is less than ninety-five percent (95%) occupied, then any
Direct Expenses affected by occupancy levels shall be grossed up to reflect an
occupancy of ninety-five percent (95%) for such period.

              (ii)  As soon as possible after the end of each calendar year,
Landlord shall provide Tenant with a statement showing the amount of Tenant's
Percentage of the actual Direct Expenses for such calendar year, the amount of
Landlord's Estimate actually paid by Tenant and the amount of the Direct
Expenses Base. Thereafter, Landlord shall reconcile the above amounts and shall
either bill Tenant for the balance due (payable on demand by Landlord) or credit
any overpayment by Tenant towards the next monthly installment of Landlord's
Estimate falling due, or refund such overpayment to Tenant at the expiration of
the Lease, as the case may be. For purposes of making these calculations, in no
event shall Tenant's Percentage of the Direct Expenses be deemed to be less than
the Direct Expenses Base.

              (iii) Within ninety (90) days after receipt of Landlord's
statement setting forth the actual Direct Expenses ("Landlord's Statement"),
Tenant shall have the right to audit at Landlord's local offices, at Tenant's
expense, Landlord's accounts and records relating to Direct Expenses. Such audit
shall be conducted by a certified public accountant approved by Landlord, which
approval shall not be unreasonably withheld. If such audit reveals that Landlord
<PAGE>
 
has overcharged Tenant, the amount overcharged shall be paid to Tenant
within thirty (30) days after the audit is concluded, together with interest
thereon at the rate of ten percent (10%) per annum, from the date that payment
of such Direct Expenses was made by Tenant until reimbursement of the overcharge
is made to Tenant.  In addition, if Landlord's Statement exceeds the actual
Direct Expenses which should have been charged to Tenant by more than five
percent (5%), the cost of the audit shall be paid by Landlord.  Tenant and
Tenant's accountant shall keep any information gained by such audit confidential
and shall not disclose such information to any other party.

              (iv)  If Landlord fails to do so within a reasonable time after
written request by Tenant, then Tenant, at its cost, shall have the right at any
time to seek a reduction in or otherwise contest any taxes or assessments for
which it is obligated to reimburse Landlord under this Article 4 and/or under
Article 10, by action or proceeding against the entity with authority to assess
or impose the same. Landlord further agrees, however, that if any action taken
by Landlord to seek a reduction in or otherwise contest any taxes or assessments
would prevent Tenant from taking any such action or otherwise prejudice Tenant's
right in such action if Landlord were unsuccessful in seeking a reduction in or
otherwise contesting such taxes or assessments, then Landlord and Tenant shall
cooperate in jointly contesting such taxes or assessments. Landlord shall not be
required to join in any proceeding or action brought separately by Tenant unless
the provisions of applicable laws or regulations or the like require that such
proceeding or action be brought by or in the name of Landlord, in which event
Landlord shall join in such proceeding or action or permit it to be brought in
Landlord's name, provided that Tenant protects, indemnifies, and holds Landlord
free and harmless from and against any liability, cost or expense in connection
with such proceeding or contest. Tenant shall continue, during the pendency of
such proceeding or action, to pay the taxes and assessments due as determined by
Landlord pursuant to this Article 4 and/or Article 10. If Tenant is successful
in such action or proceeding, Landlord shall reimburse to Tenant Tenant's share
of the reduction in taxes realized by Tenant in such contest or proceeding
within thirty (30) days after the amount of such reduction has been determined
and Landlord has received the applicable refund.

          (c) Even though the term has expired and Tenant has vacated the
Premises, when the final determination is made of Tenant's Percentage of Direct
Expenses for the year in which this Lease terminates, Tenant shall immediately
pay any increase due over the estimated expenses paid and, conversely, any
overpayment made in the event said expenses decrease shall be promptly rebated
by Landlord to Tenant.

                                   ARTICLE 5
                                   ---------
                               SECURITY DEPOSIT
                               ----------------

          (a) Upon execution of this Lease, Tenant shall have deposited with
Landlord, pursuant to Article 5 of the Sycamore Plaza I Lease, an irrevocable
standby letter of credit in the amount of One Million Seven Hundred Thousand and
no/100ths Dollars ($1,700,000.00) issued by Union Bank of California (or another
bank reasonably acceptable to Landlord), and naming Landlord as beneficiary
thereunder, as security for the faithful performance by Tenant of all of
Tenant's obligations under this Lease and the Sycamore Plaza I Lease.  The
letter of credit shall be in the form attached as EXHIBIT F to this Lease.  If
                                                  ---------                   
Tenant fails to pay when due any rent or other sum due under this Lease and such
failure continues after notice from Landlord and the expiration of any
<PAGE>
 
applicable grace period, regardless of whether Tenant has filed a petition in
bankruptcy under the federal bankruptcy laws, or if Tenant, following the filing
of any such petition, rejects this Lease or the Sycamore Plaza I Lease, then
Landlord may (but shall not be required to) draw upon the letter of credit and
use, apply or retain all or any part of the security deposit for the payment of
any rent or other sum then due and unpaid, or for the payment of any other
amount which Landlord may spend or become obligated to spend by reason of
Tenant's breach or to compensate Landlord for any other loss or damage which
Landlord may suffer by reason of Tenant's breach.  If any portion of the letter
of credit is drawn upon by Landlord for such purposes, Tenant shall, within ten
(10) days after written demand by Landlord, deposit a replacement letter of
credit with Landlord in the amount of the original letter of credit.  Tenant's
failure to do so shall be a material breach of this Lease.  The letter of
credit, or so much thereof as remains after the curing of any default of Tenant
hereunder, shall be returned to Tenant at the expiration of the Lease term and
surrender of the Premises by Tenant.

          (b) The letter of credit shall be issued for a term of at least twelve
(12) months and shall be renewed automatically for consecutive twelve (12) month
periods for the entire term of this Lease subject, however, to reduction as
provided in paragraph 5(c) or 5(d).  If at any time during the term of this
Lease Landlord does not receive written notice from the issuing bank, at least
ten (10) days prior to the expiration of any twelve (12) month term of the
letter of credit, that the letter of credit is being renewed for another twelve
(12) months, then Landlord shall have the right to draw upon the letter of
credit for the full amount thereof. Drawing upon the letter of credit shall be
conditioned only upon presentation of the original letter of credit to the
issuer thereof accompanied by a certified statement from Landlord that Tenant is
in default under the Lease which default is continuing after notice and the
expiration of any applicable grace period.  The letter of credit shall not be
mortgaged, assigned or encumbered in any manner whatsoever by Tenant.  The use,
application or retention of the letter of credit, or any portion thereof, by
Landlord shall not prevent Landlord from exercising any other right or remedy
provided by this Lease or by law, it being intended that Landlord shall not
first be required to proceed against the letter of credit, and such use,
application or retention shall not operate as a limitation on any recovery to
which Landlord may otherwise be entitled.

          (c) Provided that Tenant is not then in default under this Lease, the
total security deposit shall be reduced to One Million Two Hundred Thousand and
no/100ths Dollars ($1,200,000.00) as of April 1, 2001, and Eight Hundred
Thousand and no/100ths Dollars ($800,000.00) as of April 1, 2002.  Provided that
Tenant is not then in default under this Lease, as of April 1, 2003, and for the
balance of the term, the security deposit retained by Landlord for this Lease
shall be equal to one monthly installment of the Base Rent then payable under
this Lease.  At such time Tenant may, at Tenant's option, replace the letter of
credit with a cash deposit.

          (d) If at any time during the term of this Lease the cross-default
provision set forth in paragraph 23(a)(v) of this Lease is terminated as
provided in paragraph 24(f) or paragraph 35, Tenant shall replace the letter of
credit then held by Landlord with two (2) separate letters of credit to be held
by Landlord or, if applicable, Landlord's successor or successors-in-interest,
as security for the performance of Tenant's obligations under this Lease and the
Sycamore Plaza I Lease, respectively.  The amount of the replacement letter of
credit to be delivered by Tenant as security for this Lease shall be determined
by multiplying the amount of the letter of credit then held 
<PAGE>
 
by Landlord by a fraction, the numerator of which shall be the rentable area of
the Premises and the denominator of which shall be the total rentable area of
the Premises plus the premises occupied by Tenant under the Sycamore Plaza I
Lease. Tenant's failure to provide Landlord with the replacement letters of
credit at least ten (10) days prior to the effective date of an approved
assignment, or within ten (10) days after written notice from Landlord of a
pending transfer or conveyance of title to the Project, as applicable, shall
constitute a default under this Lease.

                                   ARTICLE 6
                                   ---------
                                      USE
                                      ---

          (a) Tenant shall use the Premises for general office, administrative,
sales demonstrations, training classes, and software development, and shall not
use or permit the Premises to be used for any other purpose without the prior
written consent of Landlord, which consent shall not be unreasonably withheld.
Nothing contained herein shall be deemed to give Tenant any exclusive right to
such use in the Project.  Tenant shall not use or occupy the Premises in
violation of law or of the certificate of occupancy issued for the Building or
Project, and shall, upon written notice from Landlord, discontinue any use of
the Premises which is declared by any governmental authority having jurisdiction
to be a violation of law or of said certificate of occupancy.  Tenant shall
comply with any direction of any governmental authority having jurisdiction
which shall, by reason of the nature of Tenant's use or occupancy of the
Premises, impose any duty upon Tenant or Landlord with respect to the Premises
or with respect to the use or occupation thereof.  Tenant's shall not do or
permit to be done anything which will invalidate or increase the cost of any
fire, extended coverage or any other insurance policy covering the Building
and/or Project and/or property located therein and shall comply with all rules,
orders, regulations and requirements of the Insurance Service Offices, formerly
known as the Pacific Fire Rating Bureau or any other organization performing a
similar function.  Tenant shall promptly, upon demand, reimburse Landlord for
any additional premium charged for such policy by reason of Tenant's failure to
comply with the provisions of this Article.  Tenant shall not do or permit
anything to be done in or about the Premises which will in any way unreasonably
obstruct or unreasonably interfere with the rights of other tenants or occupants
of the Project or Bernal Corporate Park, or injure or annoy them, or use or
allow the Premises to be used for any improper, immoral, unlawful or
objectionable purpose, nor shall Tenant cause, maintain or permit any nuisance
in, on or about the Premises.  Tenant shall not commit or suffer to be committed
any waste in or upon the Premises.

          (b) Tenant acknowledges that Landlord has recorded covenants,
conditions and restrictions against the Premises on February 18, 1987 as
Instrument Number 87/046032 in the Official Records of Alameda County (the
"CC&Rs"), a true and correct copy of which has been previously delivered to
Tenant.  Tenant's use of the Premises shall be subject to and Tenant shall
comply with the CC&R's, as the same may be amended from time to time, provided,
however, that any amendment or modification thereof shall not materially
adversely affect Tenant's use and enjoyment of the Premises or access thereto.
Tenant acknowledges that there have been and may be from time to time recorded
easements and/or declarations granting or declaring easements for parking,
utilities, fire or emergency access, and other matters.  Tenant's use of the
Premises shall be subject to and Tenant shall comply with any and all such
easements and declarations.  Tenant's use of the Premises shall be subject to
such guidelines as may from time to time be prepared by Landlord or the Bernal
Corporate Park Owner's Association in their reasonable discretion.
<PAGE>
 
          (c) Tenant acknowledges that governmental entities with jurisdiction
over the Premises may, from time to time promulgate laws, rules, plans and
regulations affecting the use of the Premises, including, but not limited to,
traffic management plans and energy conservation plans.  Tenant's use of the
Premises shall be subject to and Tenant shall comply with any and all such laws,
rules, plans, and regulations.  Notwithstanding the foregoing or anything to the
contrary contained in this Lease, Tenant shall not be responsible for compliance
with any laws, codes, ordinances, rules, regulations or other governmental
directives, including without limitation, the Americans with Disabilities Act
(collectively, "Applicable Laws") which require any alterations or improvements
to any portions of the Project other than the Premises, unless such compliance
is required solely as a result of any other alterations or improvements made to
the Premises by Tenant.  Furthermore, if any capital improvements are required
to the Premises to comply with any Applicable Laws (other than capital
improvements which are required solely as a result of any other alterations or
improvements made to the Premises by Tenant, which shall be made at Tenant's
sole expense), such improvements shall be made by Landlord and the cost of such
capital improvements, together with interest at the maximum rate allowed by law,
shall be amortized over such reasonable period as Landlord shall determine, and
Tenant shall reimburse Landlord, monthly, as additional rent, the monthly
amortized cost of such improvement that is allocable to the then remaining term
of this Lease.  Notwithstanding anything herein to the contrary Landlord shall
be solely responsible for the cost of any alterations or improvements, including
capital improvements, to the structural portions of the Building, the Building
elevators, the restrooms, and the base Building electrical, mechanical, plumbing
and HVAC systems installed by Landlord prior to the Commencement Date, and the
common areas of the Project, which are required to comply with any Applicable
Laws.

          (d) Tenant, at its sole cost, shall comply with all laws relating to
Tenant's storage, use and disposal of hazardous, toxic or radioactive matter,
including those materials identified in Sections 66680 through 66685 of Title 33
of the California Code of Regulations as they may be amended from time to time
(collectively "Toxic Materials").  If Tenant does store, use or dispose of any
Toxic Materials, other than normal amounts of cleaning supplies and office
products, Tenant shall notify Landlord in writing at least ten (10) days prior
to their first appearance on the Premises.  Landlord represents and warrants to
Tenant that, to the best of Landlord's actual knowledge without independent
investigation or inquiry, as of the date of this Lease (i) there are no
underground storage tanks located on the Project, (ii) there has been no release
onto or under the Project of any Toxic Materials in violation of applicable
environmental laws, and (iii) Landlord has received no notices of any pending
litigation, clean-up orders or other governmental action with respect to the
environmental condition of the Project.  For the purposes of this paragraph
6(d), the "actual knowledge of Landlord" shall be limited to the actual
knowledge of Loryssa Rippey and Timothy Wirta.
<PAGE>
 
                                   ARTICLE 7
                                   ---------
                                    NOTICES
                                    -------

          Any notice required or permitted to be given hereunder must be in
writing and may be given by personal delivery or by mail, and if given by mail
shall be deemed sufficiently given if sent by registered or certified mail
addressed to Tenant at the Project, or to Landlord at its address set forth at
the end of this Lease.  Either party may specify a different address for notice
purposes by written notice to the other except that the Landlord may in any
event use the Premises as Tenant's address for notice purposes.

                                   ARTICLE 8
                                   ---------
                                    BROKERS
                                    -------

          Tenant and Landlord warrants that it has had no dealings with any real
estate broker or agent in connection with the negotiation of this Lease, except
Parkway Properties, Inc. and Colliers Parrish International whose commission
shall be payable by Landlord, and that it knows of no other real estate broker
or agent who is or might be entitled to a commission in connection with the
Lease.  If Tenant or Landlord, as the case may be, has dealt with any other
person or real estate broker with respect to leasing or renting space in the
Project, Tenant or Landlord, as the case may be, shall be solely responsible for
the payment of any fee due said person or firm and Tenant or Landlord, as the
case may be, shall hold the other party free and harmless against any liability
in respect thereto, including attorneys' fees and costs.

                                   ARTICLE 9
                                   ---------
                                 HOLDING OVER
                                 ------------

          If Tenant holds over after the expiration or earlier termination of
the term hereof without the express written consent of Landlord, Tenant shall
become a Tenant at sufferance only, at a rental rate equal to one hundred
twenty-five percent (125%) of the rent in effect upon the date of such
expiration for the first sixty (60) days of any such holdover, and one hundred
fifty percent (150%) of the rent in effect upon the date of such expiration for
any holdover continuing after such 60-day period (subject to adjustment as
provided in Paragraph 4 hereof and prorated on a daily basis), and otherwise
subject to the terms, covenants and conditions herein specified, so far as
applicable.  Acceptance by Landlord of rent after such expiration or earlier
termination shall not result in a renewal of this Lease.  The foregoing
provisions of this Article 9 are in addition to and do not affect Landlord's
right of re-entry or any rights of Landlord hereunder or as otherwise provided
by law.  If Tenant fails to surrender the Premises upon the expiration of this
Lease despite demand to do so by Landlord, Tenant shall indemnify and hold
Landlord harmless from all loss or liability, including without limitation, any
claim made by any succeeding tenant founded on or resulting from such failure to
surrender and any attorneys' fees and costs.

                                  ARTICLE 10
                                  ----------
                          TAXES ON TENANT'S PROPERTY
                          --------------------------

          (a) Tenant shall be liable for and shall pay, at least ten days before
delinquency, all taxes levied against any personal property or trade fixtures
placed by Tenant in or 
<PAGE>
 
about the Premises. If any such taxes on Tenant's personal property or trade
fixtures are levied against Landlord or Landlord's property of if the assessed
value of the Premises is increased by the inclusion therein of a value placed
upon such personal property or trade fixtures of Tenant and if Landlord, after
written notice to Tenant, pays the taxes based upon such increased assessment,
which Landlord shall have the right to do regardless of the validity thereof,
but only under proper protest if requested by Tenant, Tenant shall, upon demand,
repay to Landlord the taxes so levied against Landlord, or the portion of such
taxes resulting from such increase in the assessment.

          (b) If the Tenant Improvements in the Premises, whether installed,
and/or paid for by Landlord or Tenant and whether or not affixed to the real
property so as to become a part thereof, are assessed for real property tax
purposes at a valuation higher than the valuation at which Tenant Improvements
conforming to Landlord's "Project Standard" in other space in the Project are
assessed (which for purposes of this paragraph shall mean tenant improvement
costs in excess of $30.00 per rentable square foot for hard construction costs
[i.e., exclusive of architectural and engineering fees, permit fees, and
construction management fees]), then the real property taxes and assessment
levied against the Project by reason of such excess assessed valuation shall be
deemed to be taxes levied against personal property of Tenant and shall be
governed by the provisions of Paragraph 10(a), above.   If the records of the
County Assessor are available and sufficiently detailed to serve as a basis for
determining whether said Tenant Improvements are assessed at a higher valuation
than Landlord's Project Standard, such records shall be binding on both the
Landlord and the Tenant.  If the records of the County Assessor are not
available or sufficiently detailed to serve as a basis for making said
determination, the actual cost of construction shall be used.

                                  ARTICLE 11
                                  ----------
                             CONDITION OF PREMISES
                             ---------------------

          (a) Landlord represents and warrants, that as of the Commencement
Date, to the best of its knowledge, the Premises and the Building shall be
constructed  in compliance with all Applicable Laws.  Landlord further warrants
to Tenant that the Base Building and Tenant Improvements constructed by Landlord
shall be (i) free from material structural defects and shall not violate the
CC&R's or any other covenants or restrictions of record, and (ii) constructed in
compliance in all material respects with the Base Building Plans and the Tenant
Improvement Plans approved by Landlord and Tenant subject to any changes
implemented in such plans in accordance with the procedures set forth in the
Work Letter.  Subject to the foregoing, and except as otherwise expressly
provided in this Lease, Tenant acknowledges that neither Landlord nor any agent
of Landlord has made any representation or warranty with respect to the Premises
or the Project or with respect to the suitability of either for the conduct of
Tenant's business.  Subject to Landlord's representations and warranties and
Landlord's obligation to complete any punch-list items as provided in paragraph
9 of the Work Letter, and excluding any latent defects, the taking of possession
of the Premises by Tenant shall conclusively establish that the Premises were in
satisfactory condition at such time.

          (b) If it is determined that any of the warranties in paragraph 11(a)
have been violated in any respect, then it shall be the obligation of Landlord,
after receipt of written notice from Tenant setting forth with specificity the
nature of the violation, to promptly correct the condition(s) constituting such
violation at Landlord's sole cost.  Landlord shall assign to Tenant Landlord's
rights under all contractors' and manufacturers' warranties relating to the
Tenant Improvements (provided, 
<PAGE>
 
however, that Landlord may reserve joint enforcement rights under such
warranties to the extent of Landlord's continuing obligations or warranties
hereunder), and shall cooperate with Tenant in all reasonable respects in any
enforcement of such warranties.

                                  ARTICLE 12
                                  ----------
                                  ALTERATIONS
                                  -----------

          (a) Tenant shall make no alterations, additions or improvements in or
to the Premises without Landlord's prior written consent, which shall not be
unreasonably withheld; provided, however, that Landlord's consent shall not be
required for any alterations, additions or improvements to the Premises that (i)
do not cost more than $15,000 per work of improvement nor more than $50,000
cumulatively per annum, and (ii) do not affect any structural or exterior
portion of the Building or the Building's electrical, plumbing or HVAC systems,
except that Landlord's consent shall, in any event, be required for any
demolition of any alterations, additions or improvements to the Premises.   All
work shall be performed by contractors or mechanics approved by Landlord and
shall be done in a good and workmanlike manner.  Tenant covenants and agrees
that all work done by Tenant shall be performed in full compliance with all
Applicable Laws and in full compliance with the rules, regulations and
requirements of the Insurance Service Offices formerly known as the Pacific Fire
Rating Bureau, and of any similar body.  Before commencing any work, Tenant
shall give Landlord at least ten days written notice of the proposed
commencement of such work and shall, if the cost of such alterations exceeds
$50,000 and if so requested by Landlord, secure at Tenant's own cost and
expense, a completion and lien indemnity bond, reasonably satisfactory to
Landlord, for said work.  Tenant further covenants and agrees that any
mechanic's lien filed against the Premises or against the Building or Project
for work claimed to have been done for, or materials claimed to have been
furnished to, Tenant will be discharged by Tenant, by bond or otherwise, within
ten days after the filing thereof, at the cost and expense of Tenant.  All
alterations, additions or improvements upon the Premises made by either party,
including (without limiting the generality of the foregoing) all wallcovering,
built-in cabinet work, paneling and the like, shall become the property of
Landlord, and shall remain upon, and be surrendered with the Premises, as a part
thereof, at the end of the term hereof, except that Landlord may, by written
notice to Tenant given to Tenant at the time that Landlord grants its consent to
any alterations, additions or improvements, require Tenant to remove such
alterations, additions and improvements at the expiration or sooner termination
of this Lease, and in such event Tenant shall repair all damage resulting from
such removal or, at Landlord's option, shall pay to Landlord all costs arising
from such removal. Landlord and Tenant agree, however, that the Tenant
Improvements shall become the property of Landlord upon installation and shall
remain upon and be surrendered with the Premises at the expiration or sooner
termination of this Lease, and Tenant shall have no obligation to remove the
Tenant Improvements from the Premises.

          (b) All articles of personal property and all business and trade
fixtures, machinery and equipment, furniture and movable partitions owned by
Tenant or installed by Tenant at its expense in the Premises shall be and remain
the property of Tenant and may be removed by Tenant at any time during the lease
term when Tenant is not in default hereunder.  If Tenant shall fail to remove
all of its effects from the Premises upon termination of this Lease for any
cause whatsoever, Landlord may, at its option, remove the same in accordance
with applicable law, and store said effects without liability to Tenant for loss
thereof.  In such event, Tenant agrees to pay 
<PAGE>
 
Landlord upon demand any and all expenses incurred in such removal, including
court costs and attorneys' fees and storage charges on such effects for any
length of time that the same shall be in Landlord's possession. Landlord may, at
its option, without notice, sell said effects, or any of the same, at private
sale and without legal process, for such price as Landlord may obtain and apply
the proceeds of such sale upon any amounts due under this Lease from Tenant to
Landlord and upon the expense incident to the removal and sale of said effects.

                                  ARTICLE 13
                                  ----------
                                    REPAIRS
                                    -------

          (a) Subject to Landlord's representations and warranties contained
herein and the punch list items, by entry hereunder, Tenant accepts the Premises
as being in good and sanitary order, condition and repair, excluding any latent
defects.  Tenant shall keep, maintain and preserve the Premises in good
condition and repair.  Tenant shall, upon the expiration or sooner termination
of the term hereof, surrender the Premises to Landlord in the same condition as
when received, usual and ordinary wear and tear and damage due to casualty or
condemnation excepted.  Except as expressly provided in EXHIBIT B attached
                                                        ---------         
hereto, Landlord shall have no obligation to alter, remodel, improve, decorate
or paint the Premises or any part thereof.  The parties hereto affirm that
Landlord has made no representations to Tenant respecting the condition of the
Premises or the Project except as specifically herein set forth.

          (b) Anything contained in Paragraph 13(a) above to the contrary
notwithstanding, Landlord shall repair and maintain the structural portions of
the Building, including the foundations, building shell, and roof structure, all
at Landlord's expense.  Landlord shall also repair and maintain the common areas
and the basic plumbing, elevators, life safety systems and other building
systems, including heating, ventilating, air conditioning and electrical systems
installed or furnished by Landlord, and perform roof membrane repair and
maintenance to the Premises; the cost of such repairs and maintenance shall be
included in Direct Expenses as provided in Article 4, except to the extent such
repair, maintenance or replacement is required by the gross negligence or
willful misconduct of Landlord, its agents or employees or a breach by Landlord
of its obligations under this Lease.  Landlord shall not be liable for any
failure to make any such repairs or to perform any maintenance unless such
failure shall persist for an unreasonable time after written notice of the need
of such repairs or maintenance is given to Landlord by Tenant.  Except as
provided in Article 21 hereof, there shall be no abatement of rent and no
liability of Landlord by reason of any injury to or interference with Tenant's
business arising from the making of any repairs, alterations or improvements in
or to any portion of the Building, Project or the Premises or in or to fixtures,
appurtenances and equipment therein.  Tenant waives the right to make repairs at
Landlord's expense under any law, statute or ordinance now or hereafter in
effect.

                                  ARTICLE 14
                                  ----------
                                     LIENS
                                     -----

          Tenant shall not permit any mechanic's, materialmen's or other liens
to be filed against the Building or Project, nor against Tenant's leasehold
interest in the Premises.  Landlord shall have the right at all reasonable times
to post and keep posted on the Premises any notices which it deems necessary for
protection from such liens.  If any such liens are filed, Landlord may, without
<PAGE>
 
waiving its rights and remedies based on such breach of Tenant and without
releasing Tenant from any of its obligations, cause such liens to be released by
any means it shall deem proper, including payments in satisfaction of the claim
giving rise to such lien.  Tenant shall pay to Landlord, within ten (10) days
after invoice, any sum paid by Landlord to remove such liens, together with
interest at the maximum rate per annum permitted by law from the date of such
payment by Landlord.

                                  ARTICLE 15
                                  ----------
                               ENTRY BY LANDLORD
                               -----------------

          Landlord reserves and shall with reasonable notice (except in the case
of emergencies and regularly scheduled janitorial services) have the right to
enter the Premises to inspect the same, to supply janitorial service and any
service to be provided by Landlord to Tenant hereunder, to show the Premises to
prospective purchasers or tenants (but as to tenants only during the last nine
(9) months of the term), to post notices of nonresponsibility, to alter, improve
or repair the Premises or any other portion of the Building or Project, all
without being deemed guilty of any eviction of Tenant and without abatement of
rent.  Landlord may, in order to carry out such purposes, erect scaffolding and
other necessary structures where reasonably required by the character of the
work to be performed, provided that the business of Tenant shall be interfered
with as little as is reasonably practicable.   Tenant hereby waives any claim
for damages for any injury or inconvenience to or interference with Tenant's
business, any loss of occupancy or quiet enjoyment of the Premises, and any
other loss in, upon and about the Premises.  Landlord shall at all times have
and retain a key with which to unlock all doors in the Premises, excluding
Tenant's vaults and safes.  Landlord shall have the right to use any and all
means which Landlord may deem proper to open said doors in an emergency in order
to obtain entry to the Premises provided Landlord shall promptly repair any
damage to the Premises caused by such entry.  Any entry to the Premises obtained
by Landlord by any of said means, or otherwise, shall not be construed or deemed
to be a forcible or unlawful entry into the Premises, or any eviction of Tenant
from the Premises or any portion thereof, and any damages caused to the Premises
on account thereof shall be paid by Landlord.  It is understood and agreed that
no provision of this Lease shall be construed as obligating Landlord to perform
any repairs, alterations or decorations except as otherwise expressly agreed
herein by Landlord.

                                  ARTICLE 16
                                  ----------
                            UTILITIES AND SERVICES
                            ----------------------

          (a) Landlord agrees to furnish or cause to be furnished to the
Premises the utilities and services described in the Standards for Utilities and
Services, attached hereto as EXHIBIT C, subject to the conditions and in
                             ---------                                  
accordance with the standards set forth therein.  Landlord's failure to furnish
any of the foregoing items when such failure is caused by:

                 (i)   Accident, breakage, or repairs,

                 (ii)  Strikes, lockouts or other labor disturbance or labor
dispute of any character,

                 (iii) Governmental regulation, moratorium or other
governmental action,
<PAGE>
 
                 (iv) Inability despite the exercise of reasonable diligence to
obtain electricity, water or fuel, or by

                 (v)  Any other cause beyond Landlord's reasonable control,
shall not result in any liability to Landlord.

In addition, Tenant shall not be entitled to any abatement or reduction of rent
by reason of such failure, no eviction of Tenant shall result from such failure
and Tenant shall not be relieved from the performance of any covenant or
agreement in this Lease because of such failure; provided, however, that if any
such failure shall continue for more than three (3) consecutive business days
and as result of such failure Tenant's use of or access to the Premises is
materially impaired, then Tenant shall be entitled to a proportionate abatement
of rent for the period and to the extent of such impairment if, and only if, the
failure was caused by the negligence or willful misconduct of Landlord, its
agents or employees or by a breach of this Lease by Landlord, or such abatement
of rent will be covered by Landlord's rent loss insurance.  In the event of any
failure, stoppage or interruption thereof, Landlord shall diligently attempt to
resume service promptly.

          (b) Tenant shall have the right, at Tenant's election, to provide
janitorial service to the Premises at Tenant's sole cost and expense through a
contractor approved by Landlord, which approval shall not be unreasonably
withheld, and in such event the cost of providing janitorial service to the
Premises shall be excluded from Direct Expenses.

          (c) Subject to Tenant's receipt of all necessary approvals from the
City of Pleasanton and under the CC&R's, Tenant shall have the right to install
and operate, at Tenant's sole cost and expense, an emergency power generator on
the Project at a location mutually acceptable to Landlord and Tenant.  The use
and operation of such generator, including periodic testing, shall be subject to
such reasonable rules as Landlord may establish prior to installation of the
generator.

                                  ARTICLE 17
                                  ----------
                                  BANKRUPTCY
                                  ----------

          If Tenant shall file a petition in bankruptcy under any provision of
the Bankruptcy Code as then in effect, or if Tenant shall be adjudicated a
bankrupt in involuntary bankruptcy proceedings and such adjudication shall not
have been vacated within sixty days from the date thereof, or if a receiver or
trustee shall be appointed of Tenant's property and the order appointing such
receiver or trustee shall not be set aside or vacated within sixty days after
the entry thereof, or if Tenant shall assign Tenant's estate or effects for the
benefit of creditors, or if this Lease shall, by operation of law or otherwise,
pass to any person or persons other than Tenant, then in any such event Landlord
may terminate this Lease, if Landlord so elects, with or without notice of such
election and with entry or action by Landlord.  In such case, notwithstanding
any other provisions of this Lease, Landlord, in addition to any and all rights
and remedies allowed by law or equity, shall, upon such termination, be entitled
to recover damages in the amount provided in Paragraph 23(b) hereof.  Neither
Tenant nor any person claiming through or under Tenant or by virtue of any
statute or order of any court shall be entitled to possession of the Premises
but shall surrender the Premises to landlord.  Nothing contained herein shall
limit or prejudice the right of Landlord to 
<PAGE>
 
recover damages by reason of any such termination equal to the maximum allowed
by any statute or rule of law in effect at the time when, and governing the
proceedings in which, such damages are to be proved; whether or not such amount
is greater, equal to, or less than the amount of damages recoverable under the
provisions of this Article 17.

                                  ARTICLE 18
                                  ----------
                                INDEMNIFICATION
                                ---------------

          Tenant shall indemnify, defend and hold Landlord harmless from all
claims arising from Tenant's use of the Premises or the conduct of its business
or from any activity, work, or thing done, permitted or suffered by Tenant in or
about the Premises except to the extent arising from the  negligence or willful
misconduct of Landlord, its agents, or employees or from a breach by Landlord of
its obligations under this Lease.  Tenant shall further indemnify, defend and
hold Landlord harmless from all claims arising from any breach or default in the
performance of any obligation to be performed by Tenant under the terms of this
Lease, or arising from the negligence or willful misconduct of Tenant or of its
agents or employees, and from and against all costs, attorneys' fees, expenses
and liabilities incurred in or about such claim or any action or proceeding
brought thereon.  In case any action or proceeding shall be brought against
Landlord by reason  of any such claim, Tenant upon notice from Landlord shall
defend the same at Tenant's expense by counsel approved in writing by Landlord.
Tenant, as a material part of the consideration to Landlord, hereby assumes all
risk of damage to property or injury to person in, upon or about the Premises
from any cause whatsoever except that which is caused by the failure of Landlord
to observe any of the terms and conditions of this Lease where such failure has
persisted for an unreasonable period of time after written notice of such
failure.  Tenant hereby waives all its claims in respect thereof against
Landlord.

                                  ARTICLE 19
                                  ----------
                          DAMAGE TO TENANT'S PROPERTY
                          ---------------------------

          Notwithstanding the provisions of Article 18 to the contrary, Landlord
or its agents shall not be liable for (i) any damage to any property entrusted
to employees of the Project, (ii) loss or damage to any property by theft or
otherwise, (iii) any damage to property resulting from fire, explosion, falling
plaster, steam, gas, electricity, water or rain which may leak from any part of
the Project or from the pipes, appliances or plumbing work therein or from the
roof, street or sub-surface or from any other place or resulting from dampness
or from any other cause whatsoever except to the extent any such loss or damage
is caused by the negligence or willful misconduct of Landlord,  its agents or
employees or a breach by Landlord of its obligations under this Lease and such
loss or damage is not covered by under any insurance Tenant is required to carry
pursuant to paragraph 20(a) or any other insurance Tenant elects to carry.
Landlord or its agents shall not be liable for interference with light or other
incorporeal hereditaments.  Tenant shall give prompt notice to Landlord in case
of fire or accidents in the Premises or in the Project or of defects therein or
in the fixtures or equipment of which Tenant has actual knowledge.
<PAGE>
 
                                  ARTICLE 20
                                  ----------
                                   INSURANCE
                                   ---------

          (a) Tenant shall, during the term hereof and any other period of
occupancy, at its sole cost and expense, keep in full force and effect the
following insurance:

              (i)   Standard form property insurance insuring against the perils
of fire, extended coverage, vandalism, malicious mischief, special extended
coverage ("All-Risk") and sprinkler leakage. This insurance policy shall be upon
all property owned by Tenant, for which Tenant is legally liable or that was
installed at Tenant's expense, and which is located in the Project including,
without limitation, furniture, fittings, installations, fixtures (other than
Tenant Improvements installed by Landlord), and any other personal property in
an amount not less than ninety percent of the full replacement cost thereof. In
the event that there shall be a dispute as to the amount which comprises full
replacement cost, the decision of Landlord or any mortgagees of Landlord shall
be conclusive. This insurance policy shall also be upon direct or indirect loss
of Tenant's earnings attributable to Tenant's inability to use fully or obtain
access to the Premises or Project in an amount as will properly reimburse
Tenant.

              (ii)  Commercial General Liability Insurance insuring Tenant
against any liability arising out of the lease, use, occupancy or maintenance of
the Premises and all areas appurtenant thereto. Such insurance shall be in the
amount of $5,000,000 Combined Single Limit for injury to, or death of one or
more persons in an occurrence, and for damage to tangible property (including
loss of use) in an occurrence, with such liability amount to be adjusted from
year to year to reflect increases in the Consumer Price Index. The policy shall
insure the hazards of premises and operation, contractual liability (covering
the Indemnity contained in Paragraph 18 hereof) and shall (1) name Landlord as
an additional insured, and (2) contain a cross liability provision, and (3)
contain a provision that "the insurance provided the Landlord hereunder shall be
primary and non-contributing with any other insurance available to the
Landlord."

              (iii) Workers' Compensation and Employer's Liability insurance
(as required by state law).

              (iv)  Any other form or forms of insurance as Tenant or Landlord
or any mortgagees of Landlord may reasonably require from time to time in form,
in amounts and for insurance risks against which a prudent tenant would protect
itself.

          (b) All policies shall be written in a form satisfactory to Landlord
and shall be taken out with insurance companies holding a General Policyholders
Rating of "A" and a Financial Rating of "X" or better, as set forth in the most
current issue of Bests Insurance Guide.  Within ten days after the execution of
this Lease, Tenant shall deliver to Landlord copies of policies or certificates
evidencing the existence of the amounts and forms of coverage satisfactory to
Landlord.  No such policy shall be cancelable or reducible in coverage except
after thirty days prior written notice to Landlord.  Tenant shall, within ten
days prior to the expiration of such policies, furnish Landlord with renewals or
"binders" thereof, or Landlord may order such insurance and charge the cost
thereof to Tenant as additional rent.  If Landlord obtains any insurance that is
the responsibility of Tenant under this section, Landlord shall deliver to
Tenant a written statement 
<PAGE>
 
setting forth the cost of any such insurance and showing in reasonable detail
the manner in which it has been computed.

          (c) Landlord shall, during the term hereof, keep in full force and
effect the following insurance, which Landlord shall obtain at competitive
rates:

              (i)   Commercial general liability insurance against claims for
personal injury, death or property damage arising out of the use, occupancy, or
maintenance of the Project (other than the Premises), in a combined single limit
amount of not less than $5,000,000 per occurrence, and $5,000,000 in the
aggregate. Such policy shall name Tenant as an additional insured with respect
to the common areas of the Project.

              (ii)  A policy of "all risk" or "causes of loss - special form"
property insurance on the Building, including the Tenant Improvements but
excluding Tenant's trade fixtures and equipment, in the amount of the full
replacement cost thereof as determined from time to time  by Landlord's
insurance agent, but in any event not less than every three years.

          (d) Notwithstanding any other provision of this Lease to the contrary,
Landlord and Tenant each hereby waive all rights of recovery against the other
on account of loss or damage occasioned to such waiving party for its property
or the property of others under its control to the extent that such loss or
damage is insured against under any insurance policies which may be in force at
the time of such loss or damage or which are required to be maintained by this
Lease, even if such damage may have been caused by the negligence of the other
party, its agents or employees.  Tenant and Landlord shall, upon obtaining
policies of insurance required hereunder, give notice to the insurance carrier
that the foregoing mutual waiver of subrogation is contained in this Lease and
Tenant and Landlord shall cause each insurance policy obtained by such party to
provide that the insurance company waives all right of recovery by way of
subrogation against either Landlord or Tenant in connection with any damage
covered by such policy.
 
                                  ARTICLE 21
                                  ----------
                             DAMAGE OR DESTRUCTION
                             ---------------------

          (a) If there is damage to the Premises which was caused by a peril
required to be covered or actually covered by insurance pursuant to Article 20
above ("Insured Loss"), or if there is damage to the Premises which is not an
Insured Loss but the estimated restoration cost is not more than ten percent
(10%) of the then actual replacement cost of the Premises, then, in either
event, Landlord shall repair such damage to the Premises (but not any damage to
Tenant's trade fixtures, equipment, furniture or other personal property) at
Landlord's expense, as promptly as possible, and this Lease shall continue in
full force and effect, except as otherwise provided below.

          (b) If there is damage to the Premises that is not an Insured Loss,
and the estimated restoration cost exceeds ten percent (10%) of the then actual
replacement cost of the Premises, then Landlord may, at Landlord's option,
either (i) repair such damage to the Premises (but not any damage to Tenant's
trade fixtures, equipment, furniture or other personal property), at Landlord's
expense, as promptly as possible, in which event this Lease shall continue in
full force and effect, or (ii) give notice to Tenant within thirty (30) days
after the date of the occurrence of such 
<PAGE>
 
damage of Landlord's intention to terminate this Lease as of the date of the
occurrence of such damage. If Landlord elects to terminate this Lease, Tenant
shall have the right, within ten (10) days after receipt of such notice, to give
Landlord notice of Tenant's intention to pay for the cost to restore the
Premises, in which event this Lease shall continue in full force and effect and
Landlord shall proceed to make such repairs as soon as reasonably possible after
Tenant has deposited with Landlord an amount equal to (A) the estimated cost of
such repairs less (B) ten percent (10%) of the then actual replacement cost of
the Premises. Landlord shall be responsible for such portion of the cost of the
repairs equal to ten percent (10%) of the then actual replacement cost of the
Premises. If Tenant does not give notice within such 10-day period, this Lease
shall be terminated as of the date of the occurrence of such damage.

          (c) Upon any termination of this Lease under any of  the provisions of
this Article 21, the parties shall be released without further obligation to the
other from the date possession of the Premises is surrendered to Landlord except
for items which have therefore accrued and are then unpaid.

          (d) In the event of repair, reconstruction and restoration by Landlord
as herein provided, the rental payable under this Lease shall be abated
proportionately with the degree to which Tenant's use of the Premises is
impaired during the period of such repair, reconstruction or restoration.
Tenant shall not be entitled to any compensation or damages for loss in the use
of the whole or any part of the Premises and/or any inconvenience or annoyance
occasioned by such damage, repair, reconstruction or restoration.

          (e) Notwithstanding anything to the contrary contained in this Article
21, if Landlord is delayed or prevented from completing the repair or
restoration of the damaged Premises within fifteen (15) months after the
occurrence of such damage or destruction by reason of acts of God, war,
governmental restrictions, inability to procure the necessary labor or
materials, or other cause beyond the reasonable control of Landlord, either
Landlord or Tenant may terminate this Lease as of the end of said fifteen (15)
month period.

          (f) If Landlord is obligated to or elects to repair or restore as
herein provided, Landlord shall be obligated to make repair or restoration only
of those portions of the Project and the Premises which were originally provided
at Landlord's expense, and the repair and restoration of items not provided at
Landlord's expense shall be the obligation of Tenant.

          (g) Notwithstanding anything to the contrary herein, if there is
damage to the Premises, whether or not an Insured Loss, which cannot be repaired
within one hundred eighty (180) days after the date of the casualty (the
"Estimated Rebuilding Period"), as reasonably estimated by an architect or
engineer jointly selected by Landlord and Tenant, Tenant shall have the right to
terminate this Lease as of the date of such damage.  Landlord and Tenant shall
use reasonable efforts to obtain a written estimate of the repair period within
thirty (30) days after the date of damage.  If Tenant desires to exercise its
termination option, Tenant shall give Landlord written notice of such exercise
within thirty (30) days after Tenant obtains written notice of the estimated
repair period.  If Landlord has not completed the restoration of the Premises
within sixty (60) days after the Estimated Rebuilding Period, Tenant shall have
the right to terminate this Lease upon written notice to Landlord given at any
time prior to the expiration of such 60-day period.  If Landlord is required 
<PAGE>
 
or elects to restore the Premises under the provisions of this Article 21 and
does not commence such restoration within one hundred twenty (120) days after
the date of such damage, Tenant may, at Tenant's option, terminate this Lease by
giving Landlord written notice thereof at any time prior to the expiration of
such 120-day period. In such event, this Lease shall terminate as of the date of
such notice to Landlord.

          (h) If at any time during the last year of the term of this Lease
there is a casualty to the Premises (whether or not an Insured Loss) such that
Tenant's use or occupancy of the Premises is materially impaired and the
Premises cannot be restored within thirty (30) days after the date of such
casualty, either Landlord or Tenant may terminate this Lease as of the date of
such casualty by written notice to the other within forty-five (45) days after
the date of the occurrence of such damage.  If, however, at the time of such
damage Tenant has an option to extend the term of this Lease and the time for
exercise of such option has not then expired, then Tenant shall have a period of
forty-five (45) days from the date of the casualty to elect to exercise the
option to extend by delivery of written notice to Landlord.  If Tenant exercises
such option during such 45-day period, and provided Landlord is otherwise
obligated to, or elects to repair such damage under the provisions of this
Article 21, Landlord shall, at Landlord's expense, repair such damage as soon as
reasonably possible, and this Lease shall continue in full force and effect.  If
Tenant fails to exercise such option during such 45-day period, then Landlord
may, at Landlord's option, terminate this Lease effective as of the date of the
casualty, giving notice to Tenant of Landlord's election to do so within ten
(10) days after the expiration of such 45-day period.

          (i) The provisions of California Civil Code 1932, Subsection 2, and
1933, Subsection 4, which permit termination of a lease upon destruction of the
Leased Premises, are hereby waived by Tenant; and the provisions of this Article
shall govern in case of such destruction.

                                  ARTICLE 22
                                  ----------
                                EMINENT DOMAIN
                                --------------

          In case all of the Premises, or such part thereof as shall
substantially interfere with Tenant's use and occupancy thereof, or all access
thereto, shall be taken for any public or quasi-public purpose by any lawful
power or authority by exercise of the right of appropriation, condemnation or
eminent domain, or sold to prevent such taking, either party shall have the
right to terminate this Lease effective as of the date possession is required to
be surrendered to said authority.  Tenant shall not assert any claim against
Landlord or the taking authority for any compensation because of such taking,
and Landlord shall be entitled to receive the entire amount of any award without
deduction for any estate or interest of Tenant, except that Landlord agrees that
Tenant shall be entitled to receive an amount which is not more than seven
percent (7%) of Landlord's award to compensate Tenant for the loss of Tenant's
leasehold interest.  In the event the amount of property or the type of estate
taken shall not substantially interfere with the conduct of Tenant's business,
in Tenant's good faith judgment, Landlord shall be entitled to the entire amount
of the award without deduction for any estate or interest of Tenant, Landlord
shall restore the Premises to substantially their same condition prior to such
partial taking, and a proportionate allowance shall be made to Tenant for the
rent corresponding to the time during which, and to the part of the Premises of
which, Tenant shall be so deprived on account of such taking and restoration.
Nothing contained in this paragraph shall be deemed to give Landlord any
interest in any award 
<PAGE>
 
made to Tenant for the taking of personal property and fixtures belonging to
Tenant or for Tenant's relocation expenses.

                                   ARTICLE 23
                                   ----------
                             DEFAULTS AND REMEDIES
                             ---------------------

          (a) The occurrence of any one or more of the following events shall
constitute a default hereunder by Tenant:

              (i)   The abandonment of the Premises by Tenant.

              (ii)  The failure by Tenant to make any payment of rent or
additional rent or any other payment required to be made by Tenant hereunder, as
and when due, where such failure shall continue for a period of seven (7) days
after written notice thereof from Landlord to Tenant; provided however, that any
such notice shall be in lieu of, and not in addition to, any notice required
under California Code of Civil Procedure Section 1161 regarding unlawful
detainer actions.

              (iii) The failure by Tenant to observe or perform any of the
express or implied covenants or provisions of this Lease to be observed or
performed by Tenant, other than as specified in Subparagraph 23(a)(i) or (ii)
above, where such failure shall continue for a period of thirty (30) days after
written notice thereof from Landlord to Tenant. Any such notice shall be in lieu
of, and not in addition to, any notice required under California Code of Civil
Procedure Section 1161 regarding unlawful detainer actions. If the nature of
Tenant's default is such that more than thirty (30) days are reasonably required
for its cure, then Tenant shall not be deemed to be in default if Tenant shall
commence such cure within said thirty-day period and thereafter diligently
prosecute such cure to completion.

              (iv)  (1) The making by Tenant of any general assignment for the
benefit of creditors;  (2)  the filing by or against Tenant of a petition to
have Tenant adjudged a bankrupt or 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 within sixty days);  (3)  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 days; or  (4)  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 days.

              (v)   A default by Tenant under the Sycamore Plaza I Lease
(subject to the provisions of paragraphs 24(f) and 35).

          (b) In the event of any such default by Tenant, 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.
In the event that Landlord shall elect to so terminate this Lease then Landlord
may recover from Tenant:
<PAGE>
 
              (i)   The worth at the time of award of any unpaid rent which had
been earned at the time of such termination; plus

              (ii)  The worth at the time of award of the amount by which the
unpaid rent which would have been earned after termination until the time of
award exceeds the amount of such rental loss that Tenant proves could have been
reasonably avoided; plus

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

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

As used in Subparagraph 23(b)(i) and (ii) above, the "worth at the time of
award" is computed by allowing interest at the maximum rate permitted by law.
As used in Subparagraph 23(b)(iii) above, the "worth at the time of award" is
computed by discounting such amount at the discount rate of the Federal Reserve
Bank of San Francisco at the time of award plus one percent.

          (c) 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.  No re-entry or taking possession of the Premises by Landlord
pursuant to this Paragraph 23(C) shall be construed as an election to terminate
this Lease unless a written notice of such intention is given to Tenant or
unless the termination thereof is decreed by a court of competent jurisdiction.

          (d) In the event of a default by Tenant under Paragraph 23(a)(iv)
above, the unenforceability of certain remedies to which Landlord may otherwise
be entitled under this Lease or at law shall not prevent Landlord from
exercising any other remedies that Landlord may have against Tenant for any
other default by Tenant including, without limitation, the right to draw upon
the letter of credit as provided in Article 5 of this Lease.

          (e) All rights, options and remedies of Landlord contained in this
Lease shall be constructed and held to be cumulative, and no one of them shall
be exclusive of the other, and Landlord shall have the right to pursue any one
or all of such remedies or any other remedy or relief which may be provided by
law, whether or not stated in this Lease.  No waiver of any default of Tenant
hereunder shall be implied from any acceptance by Landlord of any rent or other
payments due hereunder or any omission by Landlord to take any action on account
of such default if such default persists or is repeated, and no express waiver
shall affect defaults other than as specified in said waiver.  The consent or
approval of Landlord to or of any act by Tenant requiring Landlord's consent or
approval shall not be deemed to waive or render unnecessary Landlord's consent
or approval to or of any subsequent similar acts by Tenant.
<PAGE>
 
          (f) The chronic delinquency by Tenant in the payment of Basic Rent or
any other payments required to be paid by Tenant under this Lease shall
constitute a default hereunder by Tenant.  "Chronic delinquency" shall mean
failure by Tenant to pay Basic Rent, or any other payments required to be paid
by Tenant under this Lease within seven (7) days after written notice thereof
for any three (3) occasions (consecutive or non-consecutive) during any twelve
(12) month period.  In the event of a chronic delinquency, Landlord shall have
the right, at Landlord's option, to require that Basic Rent be paid by Tenant
quarterly, in advance.

          (g) Landlord shall not be deemed to be in default in the performance
of any obligation required to be performed by it hereunder unless and until it
has failed to perform such obligation within thirty (30) days after receipt of
written notice by Tenant to Landlord specifying the nature of such default, or
as soon as reasonably possible after notice from Tenant in the event that
Landlord's failure to perform its obligation will result in immediate threat of
personal injury or property damage.  If, however, the nature of Landlord's
obligation is such that more than thirty (30) days are required for its
performance, then Landlord shall not be deemed to be in default if it shall
commence such performance within such thirty (30) day period and thereafter
diligently prosecute the same to completion.

                                  ARTICLE 24
                                  ----------
                           ASSIGNMENT AND SUBLETTING
                           -------------------------

          (a) Tenant shall not voluntarily assign its interest in this Lease or
in the Premises, or sublease all or any part of the Premises, or allow any other
person or entity to occupy or use all or any part of the Premises, without first
obtaining Landlord's prior written consent which consent shall not be
unreasonably withheld.  Any assignment or sublease without Landlord's prior
written consent shall be voidable, at Landlord's election, and shall constitute
a default.  In no event shall Tenant be permitted to encumber this Lease or
Tenant's leasehold interest in the Premises.  No consent to any assignment or
sublease shall constitute a further waiver of the provisions of this paragraph.
Tenant shall notify Landlord in writing of Tenant's intent to sublease or assign
this Lease and Landlord shall, within thirty days of receipt of such written
notice, elect one of the following:

              (i)   Consent to such proposed assignment or sublease;

              (ii)  Refuse such consent, which refusal shall be on reasonable
grounds; or

              (iii) In the event of a proposed assignment, elect to terminate
this Lease, or in the event of a proposed sublease of all or any portion of the
Premises for the then remaining term of this Lease, elect to terminate this
Lease with respect to the portion of the Premises to be subleased.

          (b) As a condition for granting its consent to any assignment or
sublease, sixty days prior to any anticipated assignment or sublease Tenant
shall give Landlord written notice (the "Assignment Notice"), which shall set
forth the name, address and business of the proposed assignee or sublessee,
information (including references) concerning the character, ownership, and
financial condition of the proposed assignee or sublessee, and the Assignment
Date, any ownership or 
<PAGE>
 
commercial relationship between Tenant and the proposed assignee or sublessee,
and the consideration of all other material terms and conditions of the proposed
assignment or sublease, all in such detail as Landlord shall reasonably require.
If Landlord requests additional detail, the Assignment Notice shall not be
deemed to have been received until Landlord receives such additional detail, and
Landlord may withhold consent to any assignment or sublease until such
additional detail is provided to it. Further, upon any default by Tenant
hereunder, Landlord may require that the sublessee or assignee remit directly to
Landlord on a monthly basis, all monies due to Tenant by said assignee or
sublessee.

          (c) The consent by Landlord to any assignment or subletting shall not
be construed as relieving Tenant or any assignee of this Lease or sublessee of
the Premises from obtaining the express written consent of Landlord to any
further assignment or subletting or as releasing Tenant or any assignee or
sublessee of Tenant from any liability or obligation hereunder whether or not
then accrued.  In the event Landlord shall consent to an assignment or sublease,
Tenant shall pay Landlord as Additional Rent a reasonable attorneys' and
administrative fee not to exceed $500 for costs incurred in connection with
evaluating the Assignment Notice.  This section shall be fully applicable to all
further sales, hypothecations, transfers, assignments and subleases of any
portion of the Premises by any successor or assignee of Tenant, or any sublessee
of the Premises.

          (d) As used in this section, the subletting of substantially all of
the Premises for substantially all of the remaining term of this Lease shall be
deemed an assignment rather than a sublease.  Notwithstanding the foregoing,
Landlord's consent shall not be required for any assignment or sublease to a
parent, subsidiary or affiliate of Tenant or to an entity resulting from a
merger, consolidation or reorganization, or any entity or person which acquires
all or substantially all of the assets or stock of Tenant, provided that, in the
event of an assignment, the assignee first executes, acknowledges and delivers
to Landlord an agreement whereby the assignee agrees to be bound by all of the
covenants and agreements in this Lease which Tenant has agreed to keep, observe
or perform, that the assignee agrees that the provisions of this section shall
be binding upon it as if it were the original Tenant hereunder and that if the
assignment is made in connection with a merger or other acquisition, the
assignee shall have a net worth (determined in accordance with generally
accepted accounting principles consistently applied) immediately after such
assignment which is at least equal to the net worth (as so determined) of Tenant
at the commencement of this Lease.

          (e) Except as provided above, Landlord's consent to any assignment or
sublease shall not be unreasonably withheld.  A condition to such consent shall
be delivery by Tenant to Landlord of a true copy of any such assignment or
sublease.  If for any proposed assignment or sublease Tenant receives rent or
other consideration, either initially or over the term of the assignment or
sublease, in excess of the rent called for hereunder, or, in case of the
sublease of a portion of the Premises, in excess of such rent fairly allocable
to such portion, after appropriate adjustments to assure that all other payments
called for hereunder are taken into account, Tenant shall pay to Landlord as
additional rent hereunder one-half (1/2) of the excess of each such payment of
rent or other consideration received by Tenant after first deducting any
reasonable and customary brokerage commission, attorney's fees, advertising
costs, tenant improvement costs and/or tenant improvement allowances paid by
Tenant in connection with the assignment or sublease.  Such excess shall be paid
to Landlord promptly after its receipt by Tenant.  Landlord's waiver or consent
to any assignment or subletting shall not relieve Tenant from any obligation
under this Lease and Tenant 
<PAGE>
 
shall remain directly and primarily liable to Landlord under this Lease for the
full term hereof. The parties intend that the preceding sentence shall not apply
to any sublease rentals respecting a portion of the Premises that during the
entire term of this Lease was not occupied by Tenant for its own use, but was
always subleased by Tenant and/or kept vacant. For the purpose of this section,
the rent for each square foot of floor space in the Premises shall be deemed
equal.

          (f) If Landlord grants its consent to any assignment of this Lease as
provided in paragraph 24(a), the cross-default provision contained in paragraph
23(a)(v) of this Lease shall be automatically terminated as of the effective
date of such assignment.

                                  ARTICLE 25
                                  ----------
                                 SUBORDINATION
                                 -------------

          Without the necessity of any additional document being executed by
Tenant for the purpose of effecting a subordination, and at the election of
Landlord or any mortgagee with a lien on the Project or any ground lessor with
respect to the Project, this Lease shall be subject and subordinate at all times
to:

              (i)   All ground leases or underlying leases which may now exist
or hereafter be executed affecting the Project or the land upon which the
Project is situated or both,

              (ii)  The lien of any mortgage or deed of trust which may now
exist or hereafter be executed in any amount for which the Project, land, ground
leases or underlying leases, or Landlord's interest or estate in any of said
items is specified as security provided, however, that with respect to any
mortgage or deed of trust recorded against the Premises as of the Commencement
Date, Landlord obtains and delivers to Tenant prior to the Commencement Date a
non-disturbance and attornment agreement, in a form reasonably acceptable to
Tenant, executed by the holder of any such mortgage or deed of trust which
provides that in the event of any foreclosure of the mortgage or deed of trust,
or deed in lieu of foreclosure, this Lease shall not be terminated so long as
Tenant is not in default hereunder beyond any applicable grace or cure period
provided for herein. Concurrently with the execution of this Lease by Landlord,
Landlord shall obtain and deliver to Tenant a Subordination, Non-Disturbance and
Attornment Agreement in the form attached as EXHIBIT G, executed by Landlord and
                                             ---------                          
Principal Mutual Life Insurance Company.  Notwithstanding the foregoing,
Landlord shall have the right to subordinate or cause to be subordinated any
such ground leases or underlying leases or any such liens to the Lease.  In the
event that any ground lease or underlying lease terminates for any reason or any
mortgage or deed of trust is foreclosed or a conveyance in lieu of foreclosure
is made for any reason, Tenant shall, notwithstanding any subordination, attorn
to and become the Tenant of the successor in interest to Landlord, provided such
successor assumes in writing Landlord's obligations hereunder.  Tenant covenants
and agrees to execute and deliver, within ten (10) days after written request by
Landlord, and in the form requested by Landlord, any additional documents
evidencing the priority or subordination of this Lease with respect to any such
ground leases or underlying leases or the lien of any such mortgage or deed of
trust so long as such document is reasonably satisfactory Tenant and provides
for the non-disturbance of Tenant upon any termination of such ground lease or
any foreclosure of the mortgage or deed of trust as described herein.
<PAGE>
 
              (iii) The CC&R's as described in Article 6.

                                  ARTICLE 26
                                  ----------
                             ESTOPPEL CERTIFICATE
                             --------------------

          (a) Within ten days following any written request from the other,
Tenant or Landlord shall execute and deliver to the other a statement
certifying:

              (i)   The date of commencement of this Lease;

              (ii)  The fact that this Lease is unmodified and in full force and
effect (or, if there have been modifications hereto, that this Lease is in full
force and effect, and stating the date and nature of such modifications);

              (iii) The date to which the rental and other sums payable
under this Lease have been paid;

              (iv)  That there are no current defaults under this Lease by
either Landlord or Tenant except as specified in the responding party's
statement; and

              (v)   Such other matters reasonably requested by Landlord or
Tenant, as applicable.

Landlord and Tenant intend that any statement delivered pursuant to this Article
26 may be relied upon by any mortgagee, beneficiary, purchaser or prospective
purchaser of the Building or Project or any interest therein, or any equipment
lessor or purchaser of Tenant's stock or any assets of Tenant, as the case may
be.

          (b) Tenant's or Landlord's failure to deliver such statement within
such time shall be conclusive upon such party, as the case may be:

              (i)   That this Lease is in full force and effect, without
modification except as may be represented by the requesting party,

              (ii)  That there are no uncured defaults in the requesting
party's performance, and

              (iii) That not more than one month's rental has been paid in
advance.
<PAGE>
 
                                  ARTICLE 27
                                  ----------
                                    SIGNAGE
                                    -------

          (a) Subject to the receipt of all necessary approvals from the City of
Pleasanton, Tenant shall have the right to install one (1) Tenant identification
sign on the exterior of the Building and to have its name placed on the monument
tombstone at the entry to the Project.  The exact location of Tenant's building
signage shall be agreed to by Landlord and Tenant, subject to any restrictions
imposed by the City of Pleasanton and the CC&R's.  The size, design and other
physical characteristics of Tenant's signage shall be subject to the Design
Guidelines imposed by the CC&R's.  The cost of such signs, including
installation, maintenance and repair, shall be paid by Tenant.  Tenant shall
have no other right to maintain a Tenant identification sign in any other
location in, on or about the Premises, the Project, or Bernal Corporate Park and
shall not display or erect any Tenant identification sign, display or other
advertising material within the Premises that is visible from the exterior of
the Building.  If Tenant fails to maintain its exterior signage or if Tenant
fails to remove such signage upon termination of this Lease, Landlord may do so
at Tenant's expense and Tenant's reimbursement to Landlord for such amounts
shall be deemed additional rent.

          (b) The rights  to such exterior building signage and monument signage
are personal to Documentum, Inc. and may not be transferred or assigned except
to (i) a parent, subsidiary or affiliate of Documentum, Inc., or (ii) a
transferee approved in writing by Landlord pursuant to paragraph 24(a)(i) of
this Lease; provided, however, that if Landlord, in its good faith judgment and
reasonable opinion determines that any transferee approved by Landlord is not of
reputable or good character, consistent with the other tenants of the Project,
Landlord may deny such sign rights to such transferee if Landlord so notifies
Tenant in writing at the time of Landlord's consent to the proposed transfer.
If Landlord fails to so notify Tenant, the transferee approved by Landlord shall
be entitled to the same signage rights granted to Documentum, Inc. hereunder.

                                  ARTICLE 28
                                  ----------
                             RULES AND REGULATIONS
                             ---------------------

          Tenant shall faithfully observe and comply with the "Rules and
Regulations," a copy of which is attached hereto and marked EXHIBIT D,  and all
                                                            ---------          
reasonable and nondiscriminatory modifications thereof and additions thereto
from time to time put into effect by Landlord.  Landlord shall not be
responsible to Tenant for the violation or non-performance by any other tenant
or occupant of the Project of any of said Rules and Regulations.

                                  ARTICLE 29
                                  ----------
                               CONFLICT OF LAWS
                               ----------------

          This Lease shall be governed by and construed pursuant to the laws of
the State of California.
<PAGE>
 
                                  ARTICLE 30
                                  ----------
                            SUCCESSORS AND ASSIGNS
                            ----------------------

          Except as otherwise provided in this Lease, all of the covenants,
conditions and provisions of this Lease shall be binding upon and shall inure to
the benefit of the parties hereto and their respective heirs, personal
representatives, successors and assigns.

                                  ARTICLE 31
                                  ----------
                             SURRENDER OF PREMISES
                             ---------------------

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

                                  ARTICLE 32
                                  ----------
                                ATTORNEYS' FEES
                                ---------------

          If either Landlord or Tenant brings any action for any relief against
the other arising out of this Lease, the losing party shall pay to the
prevailing party its reasonable attorneys' fees and costs.(including attorneys'
fees on appeal, and costs and expenses incurred in out-of-court negotiations,
workouts and/or settlements or in seeking relief from stay or otherwise seeking
to protect its rights in any bankruptcy proceeding).  In addition, the
prevailing party shall be entitled to its attorneys' fees, costs and expenses
incurred in post-judgment proceedings to collect and enforce a judgment.  This
provision is separate and several and shall survive the merger of this Lease
into any judgment on this Lease.

                                    ARTICLE 33
                                    ----------
                             PERFORMANCE BY TENANT
                             ---------------------

          All covenants and agreements to be performed by Tenant under any of
the terms of this Lease shall be performed by Tenant at Tenant's sole cost and
expense and without any abatement of rent, except as otherwise expressly
provided herein.  If Tenant shall fail to pay any sum of money owed to any party
other than Landlord, for which it is liable hereunder or if Tenant shall fail to
perform any other act on its part to be performed hereunder and such failure
shall continue for ten (10) days after written notice thereof by Landlord (or
such longer period as may be expressly provided for in this Lease), Landlord
may, without waiving or releasing Tenant from obligations of Tenant, but shall
not be obligated to, make any such payment or perform any such other act to be
made or performed by Tenant.  All sums so paid by Landlord and all necessary
incidental costs shall be payable to Landlord within ten (10) days after demand
therefor.  Tenant covenants to pay any such sums and Landlord shall have (in
addition to any other right or remedy of Landlord) all rights and remedies in
the event of the non-payment thereof by Tenant as are set forth in Article 23
hereof.
<PAGE>
 
                                  ARTICLE 34
                                  ----------
                             MORTGAGEE PROTECTION
                             --------------------

          In the event of any default on the part of Landlord, Tenant will give
notice by registered or certified mail to any beneficiary of a deed of trust or
mortgage covering the Premises whose address shall have been furnished to
Tenant.  Such beneficiary or mortgagee shall have thirty (30) days after receipt
of written notice from Tenant specifying the nature of Landlord's default to
cure such default; provided, however, that if the nature of Landlord's
obligation is such that more than thirty (30) days are required for its
performance, then such beneficiary or mortgagee shall have such additional time
as is reasonably necessary to cure such default so long as it commences such
performance within such thirty (30) day period and thereafter diligently
prosecute the same to completion.

                                  ARTICLE 35
                                  ----------
                            DEFINITION OF LANDLORD
                            ----------------------

          The term "Landlord", as used in this Lease, so far as covenants or
obligations on the part of Landlord are concerned, shall be limited to mean and
include only the owner or owners, at the time in question, of the fee title of
the Premises or the lessees under any ground lease, if any.  In the event of any
transfer, assignment or other conveyance or transfers of any such title,
Landlord herein named (and in case of any subsequent transfers or conveyances,
the then grantor) shall be automatically freed and relieved from and after the
date of such transfer, assignment or conveyance of all liability as respects the
performance of any covenants or obligations on the part of Landlord contained in
this Lease thereafter to be performed.  Without further agreement, the
transferee of such title shall be deemed to have assumed and agreed to observe
and perform any and all obligations of Landlord hereunder, during its ownership
of the Premises.  Landlord may transfer its interest in the Premises without the
consent of Tenant and such transfer or subsequent transfer shall not be deemed a
violation on Landlord's part of any of the terms and conditions of this Lease.
In the event that Landlord transfers or conveys the Project to a third party
(other than a parent, subsidiary or affiliate of Landlord) and either retains
title to the project known as Sycamore Plaza I or transfers or conveys title to
Sycamore Plaza I to another third party (other than a parent, subsidiary or
affiliate of Landlord) the cross-default provisions set forth in paragraph
23(a)(v) shall be automatically terminated as of the date of such transfer or
conveyance.

                                  ARTICLE 36
                                  ----------
                                    WAIVER
                                    ------

          The waiver by Landlord or Tenant of any breach of any term, covenant
or condition herein contained shall not be deemed to be a waiver of any
subsequent breach of the same or any other term, covenant or condition herein
contained, nor shall any custom or practice which may grow up between the
parties in the administration of the terms hereof be deemed a waiver of or in
any way affect the right of Landlord or Tenant to insist upon the performance by
the other in strict accordance with said terms.  The subsequent acceptance of
rent hereunder by Landlord shall not be deemed to be a waiver of any preceding
breach by Tenant or any term, covenant or condition of this Lease, other than
the failure of Tenant to pay the particular rent so accepted, regardless of
Landlord's knowledge of such preceding breach at the time of acceptance of such
rent.
<PAGE>
 
                                  ARTICLE 37
                                  ----------
                           IDENTIFICATION OF TENANT
                           ------------------------

          If more than one person executes this Lease as Tenant:

              (i)   Each of them is jointly and severally liable for the
keeping, observing and performing of all of the terms, covenants, conditions,
provisions and agreements of this Lease to be kept, observed and performed by
Tenant, and

              (ii)  The term "Tenant" as used in this Lease shall mean and
include each of them jointly and severally. The act of or notice from, or notice
to refund to, or the signature of any one or more of them, with respect to the
tenancy of this Lease, including, but not limited to any renewal, extension,
expiration, termination or modification of this Lease, shall be binding upon
each and all of the persons executing this Lease as Tenant with the same force
and effect as if each and all of them had so acted or so given or received such
notice or refund or so signed.

                                  ARTICLE 38
                                  ----------
                                    PARKING
                                    -------

          The use by Tenant, its employees and invitees, of the parking
facilities of the Project shall be on the terms and conditions set forth in
EXHIBIT E attached hereto and by this reference incorporated herein and shall be
---------                                                                       
subject to such other agreement between Landlord and Tenant as may hereinafter
be established.  Tenant, its employees and invitees shall use no more than four
(4) non-exclusive parking spaces per one thousand (1,000) rentable square feet
of leased space. Tenant's parking allocation shall include twenty (20) parking
spaces designated as visitor parking for the exclusive use of Tenant's visitors,
which shall be located near the entrances to the Building and the building at
6801 Koll Center Parkway, with no more than five (5) of such visitor parking
spaces to be located at the entrance to the Building.  Tenant's visitor parking
spaces at the Project shall be located in a manner that will permit a reasonable
number of additional visitor parking spaces near the entrance to the Building
for other tenants of the Building.  Tenant's use of the parking spaces shall be
confined to the Project.  If, in Landlord's reasonable business judgment, it
becomes necessary, Landlord shall exercise due diligence to cause the creation
of cross-parking easements and such other agreements as are necessary to permit
Tenant, its employees and invitees to use parking spaces on the properties and
buildings of Bernal Corporate Park, which are separate legal parcels from the
Project.  Tenant acknowledges that other tenants of the Project and the tenants
of the other buildings, their employees and invitees, may be given the right to
park at the Project.

                                 ARTICLE 39
                                 ----------
                              TERMS AND HEADINGS
                              ------------------

          The words "Landlord" and "Tenant" as used herein shall include the
plural as well as the singular.  Words used in any gender include other genders.
The paragraph headings of this Lease are not a part of this Lease and shall have
no effect upon the construction or interpretation of any part hereof.
<PAGE>
 
                                   ARTICLE 40
                                   ----------
                             EXAMINATION OF LEASE
                             --------------------

          Submission of this instrument for examination or signature by Tenant
does not constitute a reservation of or option for lease, and it is not
effective as a lease or otherwise until execution by and delivery to both
Landlord and Tenant.

                                  ARTICLE 41
                                  ----------
                                     TIME
                                     ----

          Time is of the essence with respect to the performance of every
provision of this Lease in which time or performance is a factor.

                                  ARTICLE 42
                                  ----------
                          PRIOR AGREEMENT: AMENDMENTS
                          ---------------------------

          This Lease contains all of the agreements of the parties hereto with
respect to any matter covered or mentioned in this Lease, and no prior agreement
or understanding pertaining to any such matter shall be effective for any
purpose.  No provisions of this Lease may be amended or added to except by an
agreement in writing signed by the parties hereto or their respective successors
in interest.

                                  ARTICLE 43
                                  ----------
                                 SEPARABILITY
                                 ------------

          Any provision of this Lease which shall prove to be invalid, void or
illegal in no way affects, impairs or invalidates any other provision hereof,
any such other provisions shall remain in full force and effect.

                                  ARTICLE 44
                                  ----------
                                   RECORDING
                                   ---------

          Promptly following full execution of this Lease, Landlord and Tenant
shall execute a short form memorandum of this Lease mutually acceptable to
Landlord and Tenant.  Tenant shall be permitted to record such memorandum at
Tenant's expense.  Tenant shall, within ten (10) days after written request by
Landlord, execute and deliver to Landlord a quitclaim deed in recordable form
and prepared by Landlord, quitclaiming, releasing and remising to Landlord any
right, title and interest of Tenant in and to the Premises and the Project
pursuant to this Lease.

                                   ARTICLE 45
                                   ----------
                                   CONSENTS
                                   --------

          Whenever the consent of either party is required hereunder such
consent shall not be unreasonably withheld.
<PAGE>
 
                                  ARTICLE 46
                                  ----------
                            LIMITATION ON LIABILITY
                            -----------------------

          In consideration of the benefits accruing hereunder, Tenant and all
successors and assigns covenant and agree that, in the event of any actual or
alleged failure, breach or default under this Lease by Landlord:

          (a) The sole and exclusive remedy shall be against the Landlord's
interest in the Project;

          (b) No partner, officer, agent or employee of Landlord shall be sued
or named as a party in any suit or action (except as may be necessary to secure
jurisdiction of Landlord);

          (c) No service or process shall be made against any partner, officer,
agent or employee of Landlord (except as may be necessary to secure jurisdiction
of Landlord);

          (d) No partner, officer, agent or employee of Landlord shall be
required to answer or otherwise plead to any service of process;

          (e) No judgment will be taken against any partner, officer, agent or
employee of Landlord;

          (f) Any judgment taken against any partner, officer, agent or employee
of Landlord may be vacated and set aside at any time nunc pro nunc;

          (g) No writ of execution will ever be levied against the assets of any
partner, officer, agent or employee of Landlord;

          (h) The covenants and agreements set forth in this Article 46 are
enforceable both by Landlord and also by any  partner, officer, agent or
employee of Landlord.

          Nothing contained in this Article 46 is intended to deny Tenant or its
successors and assigns from asserting causes of action against any partner,
officer, agent or employee of Landlord that do not arise from a failure, breach
or default under this Lease by Landlord.

                                  ARTICLE 47
                                  ----------
                                    RIDERS
                                    ------

          Clauses, plats and riders, if any, signed by Landlord and Tenant and
affixed to this Lease are a part hereof.

                                  ARTICLE 48
                                  ----------
                                   EXHIBITS
                                   --------

          All Exhibits attached hereto are incorporated into this Lease.
<PAGE>
 
                                  ARTICLE 49
                                  ----------
                            MODIFICATION FOR LENDER
                            -----------------------

          If, in connection with obtaining construction, interim or permanent
financing for the Project the lender shall request reasonable modifications in
this Lease as a condition to such financing, Tenant will not unreasonably
withhold, delay or defer its consent thereto, provided that such modifications
do not increase the obligations of Tenant hereunder or materially adversely
affect the leasehold interest hereby created or Tenant's rights hereunder.

                                 ARTICLE 50
                                 ----------
                             WAIVER OF LIEN RIGHTS
                             ---------------------

          Notwithstanding anything in this Lease to the contrary, Landlord
waives any right, title and interest Landlord now has, or may hereafter have,
whether statutory or otherwise, to any trade fixtures, equipment, furniture,
signs, books and records, inventory or other personal property of Tenant
(singly, and/or collectively, "Collateral").  Landlord further agrees that
Tenant shall have the right to mortgage, pledge, hypothecate or grant a security
interest in any such Collateral as security for its obligations under any future
equipment lease or other financing arrangement related to the conduct of
Tenant's business at the Premises.  Landlord further agrees to execute and
deliver any UCC filing statement or other documentation reasonably acceptable to
Landlord that may be required to subordinate Landlord's interest in the
Collateral in connection with any such future lease or financing arrangement,
including, but not limited to, any real estate consent or waiver forms
reasonably acceptable to Landlord, including those submitted by any vendors,
equipment lessors or chattel mortgagees.  All trade fixtures, signs, equipment,
furniture, or other personal property of whatever kind or nature kept or
installed at the Premises by Tenant may be removed by Tenant in the ordinary
course of business at any time and from time to time during the term of this
Lease.  Landlord shall further acknowledge that the property covered by the
consent or waiver forms may be removed from the Premises by the vendor,
equipment lessor or chattel mortgagee at any time prior to termination of this
Lease upon any default by Tenant in the terms of such lease, chattel mortgage or
similar documents, free and clear of any claim or lien of Landlord in and to
such property provided that such lessor or mortgagee agrees in writing to give
Landlord prior notice of any intended removal and to be responsible for the
repair of any damage to the Premises caused by such removal.

                                 ARTICLE 51
                                 ----------
                               EXPANSION RIGHTS
                               ----------------

          Provided that Tenant is not then in default of any of its obligations
under this Lease, including the Work Letter, Tenant shall have a right of first
refusal to lease any portion of the remaining approximately 58,810 square feet
of the Building on the following terms and conditions (the "Additional Space").
If at any time prior to September 2, 1998, Landlord receives a written offer to
lease all or any portion of the Additional Space on terms and conditions
acceptable to Landlord, Landlord shall notify Tenant of the location and
approximate area of the Additional Space (the "Offered Space") to which such
offer applies ("Landlord's Notice").  Tenant shall have five (5) business days
after receipt of Landlord's Notice to notify Landlord in writing of Tenant's
election to lease the Offered Space.  If Tenant notifies Landlord of Tenant's
election to lease the Offered 
<PAGE>
 
Space within such five-day period, the lease of the Offered Space shall be on
the same terms and conditions set forth herein with respect to the Premises,
including Basic Rent at the rate of $2.40 per rentable square foot and a Tenant
Improvement Allowance of $26.50 per rentable square foot of the Offered Space,
with an occupancy and rent commencement date not earlier than the Commencement
Date of this Lese and not later than April 1, 2000, and Landlord and Tenant
shall amend this Lease to add the Offered Space to the Premises, increase the
Basic Rent and Tenant's Percentage, and make such other modifications to this
Lease as may be appropriate based upon the increased area of the Premises. If,
however, Tenant fails to notify Landlord of Tenant's election to lease the
Offered Space within such five-day period, Landlord shall have the right to
lease the Offered Space to any third party on such terms and conditions as
Landlord shall elect without any further notice to Tenant.

                                 ARTICLE 52
                                 ----------
                               OPTION TO EXTEND
                               ----------------

          Provided that Tenant is not in default hereunder, either at the time
of exercise or at the time the extended term commences, Tenant shall have the
option to extend the initial term of this Lease for one (1) additional period of
five (5) years ("Option Period") on the same terms, covenants and conditions
provided herein, except that upon such renewal the Basic Rent due hereunder
shall be the then fair market rental value of the Premises.  The "then fair
market rental value of the Premises" shall be defined to mean the fair market
rental value of the Premises as of the commencement of the Option Period, taking
into consideration the uses permitted under this Lease, the quality, size,
design and location of the Premises, and the rent for comparable space located
in Pleasanton.  Tenant shall exercise its option by giving Landlord written
notice ("Option Notice") at least two hundred seventy (270) days but not more
than three hundred sixty (360) days prior to the expiration of the initial term
of this Lease.  This option to extend is personal to Tenant and may not be
transferred or assigned to any third party, except Tenant affiliates and
permitted transferees pursuant to Article 24 of this Lease.
<PAGE>
 
                                 ARTICLE 53
                                 ----------
                            LANDLORD'S CONDITION 
                            -------------------- 

          This Lease is subject to the approval of Landlord's investment
committee which Landlord shall use diligent efforts to obtain no later than ten
(10) business days after this Lease has been fully executed. This condition is
for the sole benefit of Landlord and may be waived or deemed satisfied at
Landlord's option.

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

LANDLORD:

Patrician Associates, Inc., a California    ADDRESS:                       
corporation                                                                   
                                            Patrician Associates, Inc.     
By:_______________________________          c/o Parkway Properties, Inc.,  
Its:______________________________          7011 Koll Center Parkway, Suite 210 
                                            Pleasanton, California  94566  
By:_______________________________                                     
Its:______________________________                                     
                                                                       
                                            
TENANT:                                     
                                            
Documentum, Inc., a California corporation  ADDRESS:                    
                                                                        
By:_______________________________          Documentum, Inc.            
Its:______________________________          5671 Gibraltar Drive        
                                            Pleasanton, California 94588-8547
By:_______________________________
Its:______________________________
<PAGE>
 
                        OUTLINE OF TENANT'S FLOOR PLAN
                        ------------------------------














                                   EXHIBIT A
                                   ---------
<PAGE>
 
                                  THE PROJECT
                                  -----------













                                  EXHIBIT A-1
                                  -----------
<PAGE>
 
                             WORK LETTER AGREEMENT
                             ---------------------

                                   RECITALS

     A.   Concurrently with the execution of this Work Letter Agreement ("Work
Letter"), Landlord and Tenant have entered into a lease (the "Lease") covering
certain premises (the "Premises") more particularly described in EXHIBIT A-1
                                                                 -----------
attached to the Lease.  This Work Letter is attached to and made a part of the
Lease.  The capitalized terms used herein shall have the meanings set forth in
the Lease, unless otherwise defined herein.

     B.  In order to induce Tenant to enter into the Lease and in consideration
of the mutual covenants hereinafter contained, Landlord and Tenant hereby agree
as follows with respect to the construction of the Base Building and the Tenant
Improvements (defined below):

     1.  COMPLETION SCHEDULE

         Within thirty (30) days after the full execution of this Lease,
Landlord shall deliver to Tenant, for Tenant's review and approval, a schedule
(the "Work Schedule") setting forth a timetable for the planning and completion
of the Base Building and the installation of the Tenant Improvements to be
constructed in the Premises.  The Work Schedule shall set forth each of the
various items of work to be done by or approval to be given by Landlord and
Tenant in connection with the completion of the Base Building and the Tenant
Improvements.  Such schedule shall be submitted to Tenant for its approval and,
upon approval by both Landlord and Tenant, such schedule shall become the basis
for completing the Base Building and the Tenant Improvements.  If Tenant shall
fail to approve the Work Schedule, as it may be modified after discussions
between Landlord and Tenant, within seven (7) working days after the date such
schedule is first received by Tenant, the Work Schedule shall be deemed
approved.

     2.  BASE BUILDING

         Landlord shall construct at Landlord's sole expense the building shell
and improvements, including the Site Improvements defined below, but excluding
the Tenant Improvements, to be constructed at 6701 Koll Center Parkway
(collectively, the "Base Building") in all material respects in accordance with
the drawings prepared by Korth Sunseri Hagey for Sycamore Plaza, project 96108,
including  sheets A0.1 through A11.2 dated May 22, 1998, sheets S1.1 through
S4.5, E0.1 through E2.1, M2.3, P0.1 through 6.1, all dated May 15, 1998; Kier &
Wright topographic drawing C.1 dated April 30, 1998, and grading and paving
plans, notes and details C.2 through C.7 dated April 30, 1998; landscape
drawings by David Gates and Associates, sheets L0.1 through L4.1 dated May 19,
1998; and Korth Sunseri Hagey Project Manual, including specifications dated
May, 1998 (collectively, the "Base Building Plans").  The Base Building shall
include, without limitation, the building lobby (including all restrooms),
interior stairways, elevator, central HVAC system, and sprinkler system
distribution including upright heads, and, subject to receipt of all necessary
approvals from the City of Pleasanton, a covered walkway at ground level between
the Building and the building at 6801 Koll Center Parkway.  HVAC distribution
from the 

                                   EXHIBIT B
                                   ---------
                                  Page 1 of 8
<PAGE>
 
main trunk line shall be a Tenant Improvements Cost as described below.
Landlord shall complete construction of the Base Building in a good and
workmanlike manner in compliance with all Applicable Laws and the building
permit issued by the City of Pleasanton for such construction.  For purposes of
this Work Letter, the Site Improvements shall mean the parking areas, driveways,
walkways, landscaping and other improvements to the common areas of the Project
that are depicted on the site plan attached as EXHIBIT B-1 hereto and
                                               -----------           
incorporated herein.

     3.  TENANT IMPROVEMENTS

         Reference herein to "Tenant Improvements" shall include all work to be
done in the Premises pursuant to the Tenant Improvement Plans described in
Paragraph 5 below, including but not limited to partitioning, doors, ceilings,
floor coverings, finishes, (including paint and wallcovering) electrical,
(including lighting, switching, outlets, etc.) plumbing, heating, ventilating
and air conditioning, fire protection, cabinets and other mill work, all as more
particularly described therein

     4.  TENANT'S SPACE PLAN

         Tenant shall retain a space planner to prepare preliminary and final
space plans required in connection with the construction of the Tenant
Improvements to the Premises.  Tenant shall cause its space planner to prepare
and submit to Landlord, no later than April 15, 1999, a final space plan for
Tenant's proposed Tenant Improvements to the Premises ("Space Plan").  Tenant's
Space Plan shall be sufficient to enable the Architect to prepare working
drawings for the Tenant Improvements pursuant to paragraph 5 below.  Within ten
(10) business days after receipt of Tenant's Space Plan, Landlord shall notify
Tenant of Landlord's approval or disapproval thereof, specifying in reasonable
detail the basis for Landlord's disapproval, if applicable.  The architect
("Architect") shall be selected by Tenant from among the following firms:
Interform; Ambiance Associates; Gensler and Associates; Korth, Sunseri and
Hagey; RMW and Associates; Michael Willis & Associates; or other similarly
qualified architect approved by Landlord.

     5.  FINAL PRICING AND DRAWING SCHEDULE

         (a) After the preparation of the Space Plan and after Landlord's
written approval thereof, in accordance with the Work Schedule, Landlord enter
into a contract with the Architect and shall cause the Architect to prepare and
submit to Tenant the final working drawings and specifications ("Tenant
Improvement Plans").  Such working drawings shall be approved by Landlord and
Tenant in accordance with the Work Schedule.  If Tenant disapproves any part of
the Tenant Improvement Plans, Tenant's disapproval shall provide objections with
sufficient particularity for the Architect to revise the Tenant Improvements
Plans.  Such revisions shall be subject to Landlord's approval, which shall not
be unreasonably withheld.  Following final approval of the Tenant Improvement
Plans by Landlord and Tenant, such plans be submitted by Landlord to the
appropriate governmental body for plan checking and a building permit.

                                   EXHIBIT B
                                   ---------
                                  Page 2 of 8
<PAGE>
 
          (b) Concurrent with the plan checking, Landlord shall cause Devcon
Construction (the "General Contractor") to prepare and deliver to Landlord and
Tenant a final pricing for construction of the Tenant Improvements ("Final
Pricing"), taking into account any modifications which may be required to
reflect changes in the plans and specifications required by the City of
Pleasanton.  Prior to determining the Final Pricing, Landlord shall cause the
General Contractor to solicit bids from three (3) subcontractors for each of the
subtrades, including final clean-up.  Tenant shall have the right to nominate
one subcontractor to bid each of the subtrades, provided that the subcontractors
nominated by Tenant are licensed, qualified contractors experienced with jobs of
similar size and complexity and provided that such subcontractors are signatory
to appropriate labor unions.  Additionally, Tenant shall have the right to
review the bid documentation package to ensure that it allows for competitive
bidding.  If Landlord selects a subcontractor for any subtrade whose bid is five
percent (5%) greater than the lowest bid obtained by Landlord for such subtrade,
that is otherwise comparable in scope and quality to the lowest bid, then
Landlord shall be responsible for that portion of the bid in excess of one
hundred five percent (105%) of the lowest bid, which excess amount shall not be
included in the cost of the Tenant Improvements for the purpose of allocating
the same between Landlord and Tenant pursuant hereto.

          (c) Landlord shall deliver the Final Pricing, including a line item
detailed breakdown, to Tenant for Tenant's review and approval.  The Final
Pricing shall include the General Contractor's overhead and profit (not to
exceed 2.75% of the total hard construction costs, which excludes permits and
fees, plans and testing and inspections), and general conditions (not to exceed
$59,024.00) which includes supervision and clean-up during construction
(excluding final clean-up).  Landlord agrees that if Tenant reasonably deems any
subcontractor trade item to be excessively high, Landlord will cause such trade
to be rebid, but in such event any delays attributable to or resulting from such
rebidding shall be considered a Tenant Delay as described in paragraph 8(b)
below.  Tenant shall, within ten (10) business days after receipt of the Final
Pricing, notify Landlord in writing of Tenant's approval or disapproval of the
Final Pricing, which will include specific terms objected to and the reasons
therefor, if applicable.  If Tenant disapproves the Final Pricing, Landlord and
Tenant will promptly meet to discuss modifications to the Tenant Improvement
Plans and the Final Pricing.

     6.   CONSTRUCTION OF TENANT IMPROVEMENTS

          (a) After the Tenant Improvement Plans and the Final Pricing have been
approved by Landlord and Tenant and Landlord has obtained a building permit for
the Tenant Improvements, Landlord shall enter into a construction contract with
the General Contractor for installation of the Tenant Improvements in accordance
with the Tenant Improvement Plans.  Landlord shall supervise the completion of
such work and shall use diligent efforts to secure completion of the work in
accordance with the Work Schedule and this Work Letter.

          (b) Landlord shall complete construction of the Tenant Improvements in
a good and workmanlike manner in compliance with all Applicable Laws and the
building permit issued by the City of Pleasanton for such construction.
Landlord shall correct any latent defects in the Tenant Improvements and/or the
Base Building and any other incomplete or defective items that 

                                   EXHIBIT B
                                   ---------
                                  Page 3 of 8
<PAGE>
 
were not reasonably discoverable by Tenant during Tenant's walk-through
inspection of the Premises.

     7.   PAYMENT OF COST OF THE TENANT IMPROVEMENTS

          (a) Landlord shall provide Tenant with an allowance of Twenty-Six and
50/100ths Dollars ($26.50) per rentable square foot of the Premises for the
design and construction of the Tenant Improvements ("Tenant Improvement
Allowance").  In addition to the Tenant Improvement Allowance, Landlord shall
provide, at Landlord's expense, data communications conduit between the Premises
and the building at 6801 Koll Center Parkway and between these two (2) buildings
and the buildings known as Bernal Corporate Plaza I and II.

          (b) The Tenant Improvement Allowance may be used for the following
costs ("Tenant Improvement Costs"):

              (i)   Payment of the cost of preparing the space plan (not to
exceed $0.15 per square foot) and the services of the Architect, including
preparation of the final working drawings and specifications, mechanical,
electrical and structural drawings, and all other aspects of the Tenant
Improvement Plans (not to exceed $0.85 per square foot);

              (ii)  The payment of permit and license fees relating to
construction of the Tenant Improvements;

              (iii) A project management fee equal to $67,449.92 (four
percent (4%) of ($26.50 x 63,632 sq. ft.));

              (iv)  Construction of the Tenant Improvements, including,
without limitation, the following:

                    (1)  Installation within the Premises of all partitioning,
doors, floor coverings, finishes, ceilings, wall coverings and painting,
millwork and similar items;

                    (2)  All electrical wiring, lighting fixtures, outlets and
switches, and other electrical work to be installed within the Premises;

                    (3)  The furnishing and installation of all duct work,
terminal boxes, defusers and accessories required for the completion of the
heating, ventilation and air conditioning systems within the Premises, including
the cost of meter and key control for after-hour air conditioning;

                    (4)  Any additional Tenant requirements including, but not
limited to odor control, special heating, ventilation and air conditioning,
noise or vibration control or other special systems;

                                   EXHIBIT B
                                   ---------
                                  Page 4 of 8
<PAGE>
 
                    (5)  All fire and life safety control systems such as fire
walls, sprinklers, halon, fire alarms, including piping, wiring and accessories
installed within the Premises;

                    (6)  All plumbing, fixtures, pipes, and accessories to
be installed within the Premises; and

                    (7)  Landlord shall provide telephone conduit only from the
telephone jacks in the walls to the top of the ceiling at those locations
specified in the Tenant Improvement Plans. Tenant shall be responsible for
pulling all wires from the service boards to the individual jacks.

          (c) If the Tenant Improvement Costs (as determined by the Final
Pricing approved by Landlord and Tenant) exceed the Tenant Improvement
Allowance, one-half (1/2) of the excess costs shall be paid by Tenant to
Landlord in cash within thirty (30) days after Landlord has provided Tenant with
an itemized invoice for such excess costs, and the balance shall be paid by
Tenant upon substantial completion of the Tenant Improvements; provided,
however, that if such additional cost is attributable to Landlord Delays, then
such additional cost shall be paid by Landlord.

          (d) If, after the Tenant Improvement Plans and the Final Pricing have
been approved, Tenant shall require any changes or substitutions to the Tenant
Improvement Plans, one-half (1/2) of any additional costs therefor including
architectural and space planning fees, which are in excess of the Tenant
Improvement Allowance shall be paid by Tenant to Landlord within thirty (30)
days after Landlord has provided Tenant with an itemized invoice for such
additional costs, and the balance shall be paid by Tenant upon substantial
completion of the Tenant Improvements.

          (e) For purposes of this Work Letter, a "Landlord Delay" shall mean
any delay in the substantial completion of the Tenant Improvements caused by any
act or omission by Landlord, its agents or contractors, including, without
limitation, any delay (I) attributable to changes in or additions to the Base
Building Plans, the Tenant Improvement Plans and/or the Tenant Improvements
after the same have been approved by Landlord and Tenant, and (ii) attributable
to the failure of Landlord to pay when due, any amounts required to be paid by
Landlord in connection with completion of the Base Building and the Tenant
Improvements pursuant to the Lease or this Work Letter except to the extent that
such failure is due to Tenant's failure to pay any additional Tenant Improvement
Costs as required under paragraph 7(d) or 7(e) of this Work Letter.

     8.   COMPLETION AND RENTAL COMMENCEMENT DATE

          (a) The commencement of the term of this Lease and Tenant's obligation
for the payment of rental under the Lease shall not commence until substantial
completion of construction of the Base Building and the Tenant Improvements.
For purposes of the Lease and this Work Letter, "substantial completion" of the
Tenant Improvements shall mean (i) the Base Building is complete and in
compliance with all Applicable Laws and all of the Base Building systems are
operational to the extent necessary to service the Premises; (ii) Landlord has
sufficiently completed 

                                   EXHIBIT B
                                   ---------
                                  Page 5 of 8
<PAGE>
 
all the work required to be performed by Landlord in accordance with this Work
Letter (except punch-list items which Landlord shall thereafter promptly
complete as provided in paragraph 9 below) to enable Tenant to conduct its
business operations (assuming installation by Tenant of all cabling systems,
equipment, fixtures, furnishings, and other personal property necessary to
conduct its business operations); (iii) Landlord has obtained a certificate of
occupancy, or its equivalent, for the Building (except to the extent receipt of
such certificate of occupancy, or its equivalent, is delayed by any Tenant
Delay); (iv) Tenant has been provided with the parking spaces and parking
privileges to which it is entitled under the Lease; (v) Tenant has been
delivered reasonable access to the Premises sufficient to allow Tenant to
install its freestanding work stations, fixtures, furniture, equipment, and
telecommunication and computer cabling systems; and (vi) Tenant has received a
non-disturbance agreement in form reasonably acceptable to Tenant signed by
Landlord and each ground lessor, mortgagee or deed of trust holder which is of
record prior to the Commencement Date of this Lease, the receipt of which shall
be a condition to this Lease.

          (b) However, if there shall be a delay in substantial completion of
the Base Building and/or the Tenant Improvements as a result of any act or
omission of Tenant, its agents or contractors, including, without limitation,
any of the following (each, a "Tenant Delay"):  (I)  Tenant's failure to approve
any item or perform any other obligation in accordance with and by the date
specified in the Work Schedule; (ii) Tenant's request for any materials,
finishes or installations which are not readily available, if Landlord notifies
Tenant prior to final approval of the Tenant Improvement Plans that use of such
materials, finishes or installations will negatively impact the completion
schedule (including an estimate of the anticipated delays associated with such
materials, finishes or installations) and Tenant nevertheless elects to use such
materials, finishes or installations; (iii) Tenant's changes in the Tenant
Improvement Plans after their approval by Tenant; (iv) rebidding of any
subtrades at Tenant's request; or (v) interference with Landlord's work caused
by Tenant or by Tenant's contractors or subcontractors if Tenant does not cease
such interference within two (2) business days after Landlord notifies Tenant of
the existence of such interference; then the commencement of the term of this
Lease and the rental commencement date shall be accelerated by the number of
days of such delay.

     9.   PUNCHLIST

          Upon substantial completion of the Tenant Improvements, or as soon
thereafter as reasonably practicable, Landlord, Tenant and Tenant's space
planner shall inspect the Premises and the Tenant Improvements and develop a
punch-list of those minor corrections of construction or decoration details and
minor mechanical adjustments that are required to cause any applicable portion
of the Tenant Improvements to conform to the Tenant Improvement Plans.  Upon
completion of such punch-list, Landlord shall promptly commence and complete
correction of such punch-list items in a manner that minimizes interference with
Tenant's business, but in no event later than thirty (30) days after submission
of such punch-list items to Landlord, subject to reasonable availability of
necessary materials.

     10.  RISK OF LOSS
                                   EXHIBIT B
                                   ---------
                                  Page 6 of 8
<PAGE>
 
          Landlord shall bear the risk of loss for all materials, work,
installations, and decorations brought onto or installed in the Premises or the
Building by Landlord or Landlord's agents, employees or contractors in
connection with the construction of the Tenant Improvements and/or the Base
Building prior to the Commencement Date, and neither Tenant nor Tenant's agents
or employees or any party acting on behalf of Tenant shall be liable for any
damage, loss or destruction thereof.

     11.  CHANGE REQUESTS

          Any request by Tenant for a change in the Tenant Improvements after
final approval of the Tenant Improvement Plans by Landlord and Tenant (a "Change
Request") shall be presented to Landlord in writing and shall be accompanied by
all information necessary to clearly identify and explain the proposed change.
As soon as practicable after receipt of such Change Request, Landlord shall
notify Tenant in writing of the estimated cost of such Change Request as well as
the estimated increase in construction time caused by the Change Request, if
any.  Tenant shall approve such estimates in writing within two (2) business
days after receipt of Landlord's notice.  Upon receipt of such written approval,
Landlord shall be authorized to cause the General Contractor to proceed with
implementation of the Change Request.  If Tenant disputes such estimates, or
fails to approve in writing such estimates within such two (2) business day
period, Landlord shall not be required to proceed with such Change Request, and
all costs incurred by Landlord or the General Contractor in preparing such
estimates shall be included in the cost of the Tenant Improvements, which cost
shall be paid by Tenant.  If Landlord is instructed by Tenant to proceed with a
Change Request prior to determination of the increased cost or increased
construction time resulting from such Change Request and without approval of
such increase by Tenant, the amount thereof shall be determined by Landlord upon
completion of the Tenant Improvements, subject only to Landlord furnishing to
Tenant appropriate back-up information from the General Contractor concerning
the increased costs and increased construction time, if any.

                                   EXHIBIT B
                                   ---------
                                  Page 7 of 8
<PAGE>
 
     In witness whereof, this Work Letter Agreement is executed as of the date
first written above.

LANDLORD:

Patrician Associates, Inc., a California   ADDRESS:                            
corporation                                                                    
                                           Patrician Associates, Inc.          
By:_______________________________         c/o Parkway Properties, Inc.,       
Its:______________________________         7011 Koll Center Parkway,  Suite 210
                                           Pleasanton, California  94566       
By:_______________________________                                             
Its:______________________________                                             
                                                                               
TENANT:                                                                        
                                                                               
Documentum, Inc., a                        ADDRESS:                            
California corporation                                                         
                                           Documentum, Inc.          
By:_______________________________         5671 Gibraltar Drive      
Its:______________________________         Pleasanton, CA 94588-8547 

By:_______________________________
Its:______________________________



                                     
                                     
                                   EXHIBIT B
                                   ---------
                                  Page 8 of 8
<PAGE>
 
                     STANDARDS FOR UTILITIES AND SERVICES
                     ------------------------------------

          The following Standards for Utilities and Services are in effect.
Landlord reserves the right to adopt nondiscriminatory modifications and
additions hereto:

          Landlord shall:

          (a) On Monday through Friday, except holidays, from 7 A.M. to 6 P.M.
(and other times for a reasonable additional charge to be fixed by Landlord as
provided in paragraph (b) below), ventilate the Premises and furnish air
conditioning or heating on such days and hours, when in the judgment of Landlord
it may be required for the comfortable occupancy of the Premises.  The air
conditioning system achieves maximum cooling when the window coverings are
closed.  Landlord shall not be responsible for room temperatures if Tenant does
not keep all window coverings in the Premises closed whenever the system is in
operation.  Tenant agrees to cooperate fully at all times with Landlord, and to
abide by all regulations and requirements which Landlord may reasonably
prescribe for the proper function and protection of said air conditioning
system.  Tenant agrees not to connect any apparatus, device, conduit or pipe to
the Building chilled and hot water air conditioning supply lines.  Tenant
further agrees that neither Tenant nor its servants, employees, agents,
visitors, licensees or contractors shall at any time enter mechanical
installations or facilities of the Building or adjust, tamper with, touch or
otherwise in any manner affect said installations or facilities.  The cost of
maintenance and service calls to adjust and regulate the air conditioning system
shall be charged to Tenant if the need for maintenance work results from
Tenant's failure to comply with its obligations under this section, including
keeping window coverings closed as needed.  Such work shall be charged at hourly
rates equal to Landlord's actual cost.

          (b) Landlord shall furnish to Tenant after-hours heating and air
conditioning at the actual cost for such after-hours use including a reasonable
estimate of maintenance expenses attributable to such after-hours use.  No other
fees or mark-ups will be charged by Landlord for Tenant's after-hours HVAC use.
Landlord shall bill Tenant monthly for such after-hours usage and Tenant shall
pay such charges to Landlord, as additional rent, within 20 days after receipt
of Landlord's statement of such charges.

          (c) Landlord shall furnish to the Premises electric current sufficient
for normal office use.  Tenant shall be entitled to use up to four (4) watts per
rentable square foot for connected electrical power to the Premises, exclusive
of ceiling lights and electricity for operation of the HVAC system.  Any
reasonable costs for the installation and operation of any additional HVAC
equipment which may be required due to electrical usage in excess of three (3)
watts per rentable square foot of connected electrical power to the Premises,
including maintenance costs and utility charges, shall be paid by Tenant.   If a
separate meter is not installed at Tenant's cost, such excess cost will be
established by an estimate agreed upon by Landlord and Tenant, and if the
parties fail to agree, as established by an independent licensed engineer.  Said
estimates to be reviewed and adjusted quarterly.  Tenant agrees not to use any
apparatus or device in, or upon, or about the Premises which may in any way
increase the amount of such services usually furnished or supplied to said
Premises, and Tenant further agrees not to connect any apparatus or device with
wires, 

                                   EXHIBIT C
                                   ---------
                                  Page 2 of 3
<PAGE>
 
conduits or pipes, or other means by which such services are supplied, for the
purpose of using additional or unusual amounts of such services without written
consent of Landlord, which shall not be unreasonably withheld. Should Tenant use
the same to excess, the refusal on the part of Tenant to pay within ten (10)
days after demand of Landlord the amount established by Landlord for such excess
charge shall constitute a breach of the obligation to pay rent under this Lease
and shall entitle Landlord to the rights therein granted for such breach. At all
times Tenant's use of electric current shall never exceed the capacity of the
feeders to the Building or the risers or wiring installation and Tenant shall
not install or use or permit the installation or use of any computer, larger
than personal computer, or electronic data processing equipment in the Premises,
without the prior written consent of Landlord, which shall not be unreasonably
withheld.

          (d) Water will be available in public areas for drinking and lavatory
purposes only, but if Tenant requires, uses or consumes water for any purposes
in addition to ordinary drinking and lavatory purposes of which fact Tenant
constitutes Landlord to be the sole judge, in its reasonable opinion, Landlord
may install a water meter and thereby measure Tenant's water consumption for all
purposes.  Tenant shall pay Landlord for the cost of the meter and the cost of
the installation thereof and throughout the duration of Tenant's occupancy,
Tenant shall keep said meter and installation equipment in good working order
and repair at Tenant's own cost and expense, in default of which Landlord may
cause such meter and equipment to be replaced or repaired and collect the cost
thereof from Tenant.  Tenant agrees to pay for water consumed, as shown on said
meter, as and when bills are rendered, and on default in making such payment,
Landlord may pay such charges and collect the same from Tenant.  Any such costs
or expenses incurred, or payments made by Landlord for any of the reasons or
purposes hereinabove stated shall be deemed to be additional rent payable by
Tenant and collectible by Landlord as such.

          (e) Provide janitor service to the Premises, provided the same are
kept reasonably in order by Tenant, and if to be kept clean by Tenant, no one
other than persons approved by Landlord shall be permitted to enter the Premises
for such purposes.  If the Premises are not used exclusively as offices
(including Tenant's climate-controlled room), they shall be kept clean and in
order by Tenant, at Tenant's expense, and to the satisfaction of Landlord, and
by persons approved by Landlord.  Tenant shall pay to Landlord the cost of
removal of any of Tenant's refuse and rubbish, to the extent that the same
exceeds the refuse and rubbish usually attendant upon the use of the Premises as
offices.

          (f) Landlord reserves the right to stop service of the elevator,
plumbing, ventilation, air conditioning and electric systems, when necessary, by
reason of accident or emergency or for repairs, alterations or improvements
which, in the good faith judgment of Landlord, are necessary, until said
repairs, alterations or improvements shall have been completed.  Landlord shall
provide Tenant with such prior notice of any intended stoppage in service as is
reasonable under the circumstances.  Landlord shall have no responsibility or
liability for failure to supply elevator facilities, plumbing, ventilating, air
conditioning or electric service, when prevented from so doing by strike or
accident or by any cause beyond Landlord's reasonable control, or by laws,
rules, orders, ordinances, directions, regulations or requirements of any
federal, state, county or municipal authority or  inability by exercise of
reasonable diligence by Landlord to obtain gas, oil or other suitable fuel.  It
is expressly understood and agreed that any covenants on Landlord's part 

                                   EXHIBIT C
                                   ---------
                                  Page 3 of 3
<PAGE>
 
to furnish any service pursuant to any of the terms, covenants, conditions,
provisions or agreements of this Lease, or to perform any act or thing for the
benefit of Tenant, shall not be deemed breached if Landlord is unable to furnish
or perform the same by virtue of a strike or labor trouble or any other cause
whatsoever beyond Landlord's control.

                                   EXHIBIT C
                                   ---------
                                  Page 4 of 3
<PAGE>
 
                             RULES AND REGULATIONS
                             ---------------------
                             Sycamore Plaza I & II

     1.  Except as specifically provided in the Lease to which these Rules and
Regulations are attached, no sign, placard, picture, advertisement, name or
notice shall be installed or displayed on any part of the outside or inside of
the Building without the prior written consent of Landlord, which shall not be
unreasonably withheld  Landlord shall have the right to remove, at Tenant's
expense and without notice, any sign installed or displayed in violation of this
rule.

     2.  If Landlord reasonably objects in writing to any curtains, blinds,
shades, screens or hanging plants or other similar objects attached to or used
in connection with any window or door of the Premises, or placed on any
windowsill, which is visible from the exterior of the Premises, Tenant shall
immediately discontinue such use.  Tenant shall not place anything against or
near glass partitions or doors or windows which may appear unsightly from
outside the Premises.

     3.  Tenant shall not obstruct any sidewalks, halls, passages, exits,
entrances, elevators, escalators, or stairways of the Project.  The halls,
passages, exits, entrances, elevators, and stairways are not open to the general
public, but are open, subject to reasonable regulation, to Tenant's business
invitees.  Landlord shall in all cases retain the right to control and prevent
access thereto of all persons whose presence in the reasonable judgment of
Landlord would be prejudicial to the safety, character and reputation of the
Project; provided that nothing herein contained shall be construed to prevent
such access to persons with whom any tenant normally deals in the ordinary
course of its business, unless such persons are engaged in illegal or unlawful
activities.  No tenant and no employee or invitee of any tenant shall go upon
the roof of any building of the Project.

     4.  The directory of the building will be provided exclusively for the
display of the name and location of tenants only, and Landlord reserves the
right to exclude any other names therefrom.

     5.  Intentionally deleted.

     6.  Landlord will furnish Tenant, free of charge, with two keys to each
door lock in the Premises.  Landlord may make a reasonable charge for any
additional keys.  Tenant shall not alter any lock or install a new additional
lock or bolt on any door of its Premises.  Tenant, upon the termination of its
tenancy, shall deliver to Landlord the keys of all doors which have been
furnished to Tenant, and in the event of loss of any keys so furnished, shall
pay Landlord therefor.

     7.  If Tenant requires telegraphic, telephonic, burglar alarm or similar
services, it shall first obtain, and comply with, Landlord's written
instructions, if any, in their installation.

     8.  Tenant shall not place a load upon any floor of the Premises which
exceeds the load per square foot which such floor was designed to carry and
which is allowed by law.  Landlord shall have the right to prescribe the weight
of all equipment or other machinery or apparatus brought into the Project.
Heavy objects shall, if considered necessary by Landlord, stand on such
platforms as determined by Landlord to be reasonably necessary to properly
distribute the weight, which 

                                   EXHIBIT D
                                   ---------
                                  Page 1 of 5
<PAGE>
 
platforms shall be provided at Tenant's expense. Business machines and
mechanical equipment belonging to Tenant, which cause noise or vibration that
may be transmitted to the structure of the Premises to such a degree to be
objectionable to Landlord, shall be placed and maintained by Tenant, at Tenant's
expense, on vibration eliminators or other devices sufficient to eliminate noise
or vibration. The moving companies employed to move such equipment in or out of
the Premises must be reasonably acceptable to Landlord. Landlord will not be
responsible for loss of, or damage to, any such equipment or other property from
any cause, and all damage done to the Premises, by maintaining or moving such
equipment or other property shall be repaired at the expense of Tenant.

     9.  Tenant shall not use or keep in the Premises any kerosene, gasoline or
inflammable or combustible fluid or material other than those limited quantities
necessary for the operation or maintenance of office equipment.  Tenant shall
not use or permit to be used in the Premises any foul or noxious gas or
substance, or permit or allow the Premises to be occupied or used in a manner
injurious to Landlord or other occupants of the Project by reason of noise,
odors or vibrations, nor shall Tenant bring into or keep in or about the
Premises any birds or animals.

     10.  Tenant shall not use any method of heating or air-conditioning other
than that supplied by Landlord.

     11.  Tenant shall not waste electricity, water or air-conditioning and
agrees to cooperate fully with Landlord to assure the most effective operation
of the Premises' heating and air-conditioning and to comply with any
governmental energy-saving rules, laws or regulations of which Tenant has actual
notice.  Tenant shall keep corridor doors closed, and shall close window
coverings at the end of each business day.

     12.  Landlord reserves the right, exercisable with notice but without
liability to Tenant, to change the name and street address of the Premises.

     13.  Landlord reserves the right to exclude from the Project between the
hours of 6 p.m. and 7 a.m. the following day, or such other hours as may be
established from time to time by Landlord, and on Sundays and legal holidays,
any person unless that person is known to the person or employee in charge of
the Project and has a pass or is properly identified.  Tenant shall be
responsible for all persons for whom it requests passes and shall be liable to
Landlord for all acts of such persons.  Landlord shall not be liable for damages
for any error with regard to the admission to or exclusion from the Project of
any person.  Landlord reserves the right to prevent access to the Project in
case of invasion, mob, riot, public excitement or other commotion by closing the
doors or by other appropriate action.

     14.  Tenant shall close and lock the doors of its Premises and entirely
shut off all water faucets or other water apparatus, and electricity, gas or air
outlets before tenant and its employees leave the Premises.

     15.  Tenant shall not obtain for use on the Premises ice, drinking water,
food beverages, towel or other similar services upon the Premises, except at
such hours and under such regulations 

                                   EXHIBIT D
                                   ---------
                                  Page 2 of 5
<PAGE>
 
as may be fixed by Landlord. The foregoing shall not, however, prevent Tenant
from installing and operating a refrigerator, coffee maker and/or microwave oven
in any kitchen or lunchroom in the Premises.

     16.  The toilet rooms, toilets, urinals, wash bowls and other apparatus
shall not be used for any purpose other than that for which they were
constructed and no foreign substance of any kind whatsoever shall be thrown
therein.  The expense of any breakage, stoppage of damage resulting from the
violation of this rule shall be borne by the tenant who, or whose employees or
invitees, shall have caused it.

     17.  Tenant shall not sell, or permit the sale at retail, of newspapers,
magazines, periodicals, theater tickets or any other goods or merchandise to the
general public in or on the Premises.  Tenant shall not make any room-to-room
solicitation of business from other tenants in the Project.  Tenant shall not
use the Premises for any business or activity other than that specifically
provided for in Tenant's Lease.

     18.  Tenant shall not install any radio or television antenna, loudspeaker
or other devices on the roof or exterior walls of the Premises.  Tenant shall
not interfere with radio or television broadcasting or reception from or in the
Project or elsewhere.

     19.  Tenant shall not mark, drive nails, screw or drill into the
partitions, woodwork or plaster or in any way deface the Premises or any part
thereof, except in accordance with the provisions of the Lease pertaining to
alterations.  Tenant shall not cut or bore holes for wires.  Tenant shall not
affix any floor covering to the floor of the Premises in any manner except as
reasonably approved by Landlord.  Tenant shall repair any damage resulting from
noncompliance with this rule.

     20.  Tenant shall not install, maintain or operate upon the Premises any
vending machines without the written consent of Landlord, which shall not be
unreasonably withheld.

     21.  Canvassing, soliciting and distributing of handbills or any other
written material, and peddling in the Project are prohibited, and Tenant shall
cooperate to prevent such activities.

     22.  Landlord reserves the right to exclude or expel from the Project any
person who, in Landlord's good faith judgment, is intoxicated or under the
influence of liquor or drugs or who is in violation of any of the Rules and
Regulations of the Project.

     23.  Tenant shall store all its trash and garbage within its Premises or in
other facilities provided by Landlord at the Premises.  Tenant shall not place
in any trash box or receptacle any material which cannot be disposed of in the
ordinary and customary manner of trash and garbage disposal.  All garbage and
refuse disposal shall be made in accordance with directions reasonably issued
from time to time by Landlord.

     24.  The Premises shall not be used for the storage of merchandise held for
sale to the general public, or for lodging or for manufacturing of any kind, nor
shall the Premises be used for 

                                   EXHIBIT D
                                   ---------
                                  Page 3 of 5
<PAGE>
 
any improper, immoral or objectionable purpose. No cooking shall be done or
permitted on the Premises without Landlord's consent, except that use by Tenant
of Underwriter's Laboratory approved equipment for brewing coffee, tea, hot
chocolate and similar beverages or use of microwave ovens for employee use shall
be permitted, provided that such equipment and use is in accordance with all
applicable federal, state, county and city laws, codes, ordinances, rules and
regulations.

     25.  Tenant shall not use in the Premises any hand truck except those
equipped with rubber tires and side guards or such other material-handling
equipment as Landlord may approve.  Tenant shall not bring any other vehicles of
any kind into the Premises.

     26.  Without the written consent of Landlord, Tenant shall not use the name
of the Project in connection with or in promoting or advertising the business of
Tenant except as Tenant's address.

     27.  Tenant shall comply with all safety, fire protection and evacuation
procedures and regulations established by Landlord or any governmental agency.

     28.  Tenant and its employees, guests and invitees shall not enter into the
waterways located in the Project. No object of any kind may be floated or
submerged in the waterways, and no foreign substance of any kind may be thrown
in the waterways. The expense of any breakage or damage to any mechanical
equipment related to the waterways resulting from violation of this rule or any
expense incurred restoring the waterways to their normal condition shall be
borne by the tenant who, or whose employees or invitees, shall have caused such
damage.

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

     30.  Tenant's requirements will be attended to only upon written request to
the Project management office by an authorized individual.  Employees of
Landlord shall not perform any work or do anything outside of their regular
duties unless under special instructions from Landlord, and no employee of
Landlord will admit any person (Tenant or otherwise) to any office without
specific instructions from Landlord.

     31.  Landlord may waive any one or more of these Rules and Regulations for
the benefit of Tenant or any other tenant, but no such waiver by Landlord shall
be construed as a waiver of such Rules and Regulations in favor of Tenant or any
other tenant, nor prevent Landlord from thereafter enforcing any such Rules and
Regulations against any or all of the tenants of the Project.

     32.  These Rules and Regulations are in addition to, and shall not be
construed to in any way modify or amend, in whole or in part, the terms,
covenants, agreements and conditions of Tenant's lease of its Premises in the
Project.


                                   EXHIBIT D
                                   ---------
                                  Page 4 of 5
<PAGE>
 
     33.  Landlord reserves the right to make such other and reasonable Rules
and Regulations as, in its judgment, may from time to time be needed for safety
and security, for care and cleanliness of the Project and for the preservation
of good order therein, provided that any such Rules and Regulations do not
materially impair Tenant's use of or access to the Premises.  Tenant agrees to
abide by all such Rules and Regulations hereinabove stated and any additional
rules and regulations which are adopted.  In particular, tenant shall comply at
all times with the City of Pleasanton's Transportation Systems Management
Ordinance (TSM Ordinance, Chapter 17.24, Pleasanton Municipal Code), as said
Ordinance may be amended from time to time."

     34.  Tenant shall be responsible for the observance of all of the foregoing
rules by Tenant's employees, agents, clients, customers, invitees and guests.

                                   EXHIBIT D
                                   ---------
                                  Page 5 of 5
<PAGE>
 
                         PARKING RULES AND REGULATIONS
                         -----------------------------

The following rules and regulations shall govern use of the parking facilities
which are appurtenant to the Building.

     1.  All claimed damage or loss must be reported and itemized in writing
delivered to the Landlord within ten business days after any claimed damage or
loss occurs or as promptly as practicable.  Court actions by Tenant for any
claim must be filed in the court of jurisdiction where a claimed loss occurred.
Landlord is not responsible for damage by water, fire, or defective brakes, or
parts, or for the act of omissions of others, or for articles left in the car.
Landlord is not responsible for loss of use.

     2.  Tenant shall not park or permit the parking of any vehicle under its
control in any parking areas designated by Landlord as areas for parking by
visitors to the Building.  Tenant shall not leave vehicles in the parking areas
overnight (other than company-owned automobiles which may be parked overnight in
a designated location agreed to by Landlord and Tenant) nor park any vehicles in
the parking areas other than automobiles, motorcycles, motor driven or non-motor
driven bicycles or four-wheeled trucks.

     3.  Parking stickers or any other device or form of identification supplied
by Landlord as a condition of use of the Parking Facilities shall remain the
property of Landlord.  Such parking identification device must be displayed as
requested and may not be mutilated in any manner.  The serial number of the
parking identification device may not be obliterated.  Devices are not
transferable and any device in the possession of an unauthorized holder will be
void.

     4.  No extended term storage of vehicles shall be permitted.  Overnight
parking of company-owned automobiles only shall be permitted in a designated
location agreed to by Landlord and Tenant.

     5.  Vehicles must be parked entirely within the painted stall lines of a
single parking stall.

     6.  All directional signs and arrows must be observed.

     7.  The speed limit within all parking areas shall be 5 miles per hour.

     8.  Parking is prohibited:

         (a)  in areas not striped for parking;

         (b)  in aisles;

         (c)  where "no parking" signs are posed;

         (d)  on ramps;

                                   EXHIBIT E
                                   ---------
                                  Page 1 of 2
<PAGE>
 
         (e)  in cross hatched areas; and

         (f)  in such other areas as may be designated by Landlord or
              Landlord's Parking Operator.

     9.   Every parker is required to park and lock his own vehicle.  All
responsibility for damage to vehicles is assumed by the parker.

     10.  Loss or theft of parking identification devices from automobiles must
be reported immediately, and a lost or stolen report must be filed by the
customer at that time.  Landlord has the right to exclude any car from the
parking facilities that does not have an identification.

     11.  Any parking identification devices reported lost or stolen found on
any unauthorized car will be confiscated and the illegal holder will be subject
to prosecution.

     12.  Any lost or stolen parking identification devices which are found must
be reported immediately to avoid confusion.

     13.  Washing, waxing, cleaning or servicing of any vehicle in any area not
specifically reserved for such purpose is prohibited.

     14.  Landlord reserves the right to refuse the sale of monthly stickers or
other parking identification devices to any tenant or person and/or his agents
or representatives who willfully refuse to comply with these Rules and
Regulations and all unposted City, State or Federal ordinances, laws or
agreements.

     15.  Landlord reserves the right to modify and/or adopt such other
reasonable and non-discriminatory rules and regulations for the parking
facilities as it deems necessary for the operation of the parking facilities.
Landlord may refuse to permit any person who violates these rules to park in the
parking facilities, and any violation of the rules shall subject the car to
removal.

                                   EXHIBIT E
                                   ---------
                                  Page 2 of 2