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                                                                   EXHIBIT 10.13

                                LEASE AGREEMENT

        THIS LEASE, made this 26th day of June, 1997 between JOHN ARRILLAGA,
Trustee, or his Successor Trustee, UTA dated 7/20/77 (JOHN ARRILLAGA SURVIVOR'S
TRUST) as amended, and RICHARD T. PEERY, Trustee, or his Successor Trustee, UTA
dated 7/20/77 (RICHARD T. PEERY SEPARATE PROPERTY TRUST) as amended, hereinafter
called Landlord, and SMITHKLINE BEECHAM CORPORATION, a Pennsylvania corporation,
hereinafter called Tenant.

                                  WITNESSETH:

        Landlord hereby leases to Tenant and Tenant hereby hires and takes from
Landlord those certain premises (the "Premises") outlined in red on Exhibit "A",
attached hereto and incorporated herein by this reference thereto more
particularly described as follows:

A portion of that certain 48,000 (plus or minus) square foot, one-story building
located at 3233 Scott Blvd., Suite 102, Santa Clara, California 95054,
consisting of approximately 30,600 (plus or minus) square feet of space. Said
Premises is more particularly shown within the area outlined in Red on Exhibit A
attached hereto. The entire parcel, of which the Premises is a part, is shown
within the area outlined in Green on Exhibit A attached. The Premises is leased
on an "as-is" basis, in its present condition, and in the configuration as shown
in Red on Exhibit B attached hereto.

        The word "Premises" as used throughout this lease is hereby defined to
include the nonexclusive use of landscaped areas, sidewalks and driveways in
front of or adjacent to the Premises, and the nonexclusive use of the area
directly underneath or over such sidewalks and driveways. The gross leasable
area of the building shall be measured from outside of exterior walls to outside
of exterior walls, and shall include any atriums, covered entrances or egresses
and covered loading areas.

        Said letting and hiring is upon and subject to the terms, covenants and
conditions hereinafter set forth and Tenant covenants as a material part of the
consideration for this Lease to perform and observe each and all of said terms,
covenants and conditions. This Lease is made upon the conditions of such
performance and observance.

1.  USE Tenant shall use the Premises only in conformance with applicable
governmental laws, regulations, rules and ordinances for the purpose of general
office, light manufacturing, research and development, and storage and other
uses necessary for Tenant to conduct Tenant's business, provided that such uses
shall be in accordance with all applicable governmental laws and ordinances, and
for no other purpose. Tenant shall not do or permit to be done in or about the
Premises nor bring or keep or permit to be brought or kept in or about the
Premises anything which is prohibited by or will in any way increase the
existing rate of (or otherwise affect) fire or any insurance covering the
Premises or any part thereof, or any of its contents, or will cause a
cancellation of any insurance covering the Premises or any part thereof, or any
of its contents. Tenant shall not do or permit to be done anything in, on or
about the Premises which will in any way obstruct or interfere with the rights
of other tenants or occupants of the Premises or neighboring premises 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. No sale by auction shall be
permitted on the Premises. Tenant shall not place any loads upon the floors,
walls, or ceiling which endanger the structure, or place any harmful fluids or
other materials in the drainage system of the building, or overload existing
electrical or other mechanical systems. No waste materials or refuse shall be
dumped upon or permitted to remain upon any part of the Premises or outside of
the building in which the Premises are a part, except in trash containers placed
inside exterior enclosures designated by Landlord for that purpose or inside of
the building proper where designated by Landlord. No materials, supplies,
equipment, finished products or semi-finished products, raw materials or
articles of any nature shall be stored upon or permitted to remain outside the
Premises. Tenant shall not place anything or allow anything to be placed near
the glass of any window, door partition or wall which may appear unsightly from
outside the Premises. No loudspeaker or other device, system or apparatus which
can be heard outside the Premises shall be used in or at the Premises without
the prior written consent of Landlord. Tenant shall not commit or suffer to be
committed any waste in or upon the Premises. Tenant shall indemnify, defend and
hold Landlord harmless against any loss, expense, damage, reasonable attorneys'
fees, or liability arising out of failure of Tenant to comply with any
applicable law. Tenant shall comply with any covenant, condition, or restriction
("CC&R's") affecting the Premises. The provisions of this paragraph are for the
benefit of Landlord only and shall not be construed to be for the benefit of any
tenant or occupant of the Premises. There are no CC&R's affecting the Premises
at the time of Lease execution. In the event CC&R's are subsequently
implemented, Landlord shall provide a copy of said CC&R's to Tenant.

2.  TERM*

    A.  The term of this Lease shall be for a period of FIVE (5) years one (1)
month and SEVENTEEN (17) days (unless sooner terminated as hereinafter provided)
and, subject to Paragraphs 2B and 3, shall commence on the 15th day of August,
1997 and end on the 30th day of September, 2002.

    B.  Possession of the Premises shall be deemed tendered and the term of the
Lease shall commence on July 15, 1997, or

        (d) As otherwise agreed in writing.

*   It is agreed in the event said Lease commences on a date other than the
    first day of the month the term of the Lease will be extended to account for
    the number of days in the partial month. The Basic Rent during the resulting
    partial month will be pro-rated (for the number of days in the partial
    month) at the Basic Rent rate scheduled for the projected commencement date
    as shown in Paragraph 39.

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3.   POSSESSION  If Landlord, for any reason whatsoever, cannot deliver
possession of said premises to Tenant at the commencement of the said term, as
hereinbefore specified, this Lease shall not be void or voidable; no obligation
of Tenant shall be affected thereby; nor shall Landlord or Landlord's agents be
liable to Tenant for any loss or damage resulting therefrom; but in that event
the commencement and termination dates of the Lease, and all other dates
affected thereby shall be revised to conform to the date of Landlord's delivery
of possession, as specified in Paragraph 2B above. The above is, however,
subject to the provision that the period of delay of delivery of the Premises
shall not exceed 30 days from the commencement date herein (except those delays
caused by Acts of God, strikes, war, utilities, governmental bodies, weather,
unavailable materials, and delays beyond Landlord's control shall be excluded in
calculating such period) in which instance Tenant, at its option, may, by
written notice to Landlord, terminate this Lease.

4.   RENT

     A.   Basic Rent. Tenant agrees to pay to Landlord at such place as Landlord
may designate without deduction, offset, prior notice, or demand, and Landlord
agrees to accept as Basic Rent for the leased Premises the total sum of THREE
MILLION EIGHT HUNDRED FIFTY FIVE THOUSAND SIX HUNDRED AND NO/100 Dollars
($3,855,600.00) in lawful money of the United States of America, payable as
follows:

     See Paragraph 39 for Basic Rent Schedule

     B.   Time for Payment. Full monthly rent is due in advance on the first day
of each calendar month. In the event that the term of this Lease commences on a
date other than the first day of a calendar month, on the date of commencement
of the term hereof Tenant shall pay to Landlord as rent for the period from such
date of commencement to the first day of the next succeeding calendar month that
proportion of the monthly rent hereunder which the number of days between such
date of commencement and the first day of the next succeeding calendar month
bears to thirty (30). In the event that the term of this Lease for any reason
ends on a date other than the last day of a calendar month, on the first day of
the last calendar month of the term hereof Tenant shall pay to Landlord as rent
for the period from said first day of said last calendar month to and including
the last day of the term hereof that proportion of the monthly rent hereunder
which the number of days between said first day of said last calendar month and
the last day of the term hereof bears to thirty (30).

     C.   Late Charge. Notwithstanding any other provision of this Lease, if
Tenant is in default in the payment of rental as set forth in this Paragraph 4
when due, or any part thereof, Tenant agrees to pay Landlord, in addition to the
delinquent rental due, a late charge for each rental payment in default ten (10)
days. Said late charge shall equal ten percent (10%) of each rental payment so
in default.

     D.   Additional Rent. Beginning with the commencement date of the term of
this Lease, Tenant shall pay to Landlord or to Landlord's designated agent in
addition to the Basic Rent and as Additional Rent the following:

          (a)  All Taxes relating to the Premises as set forth in Paragraph 9,
and
          (b)  All insurance premiums relating to the Premises, as set forth in
Paragraph 12, and

          (c)  All charges, costs and expenses, which Tenant is required to pay
hereunder, together with all interest and penalties, costs and expenses
including reasonable attorneys' fees and legal expenses, that may accrue thereto
in the event of Tenant's failure to pay such amounts, and all damages,
reasonable costs and expenses which Landlord may incur by reason of default of
Tenant or failure on Tenant's part to comply with the terms of this Lease. In
the event of nonpayment by Tenant of Additional Rent, Landlord shall have all
the rights and remedies with respect thereto as Landlord has for nonpayment of
rent.

     The Additional Rent due hereunder shall be paid to Landlord or Landlord's
agent (i) within five days for taxes and insurance and within thirty days for
all other Additional Rent items after presentation of invoice from Landlord or
Landlord's agent setting forth such Additional Rent and/or (ii) at the option of
Landlord, Tenant shall pay to Landlord monthly, in advance, Tenant's prorata
share of an amount estimated by Landlord to be Landlord's approximate average
monthly expenditure for such Additional Rent items, which estimated amount shall
be reconciled within 120 days of the end of each calendar year or more
frequently if Landlord elects to do so at Landlord's sole and absolute
discretion as compared to Landlord's actual expenditure for said Additional Rent
items, with Tenant paying to Landlord, upon demand, any amount of actual
expenses expended by Landlord in excess of said estimated amount, or Landlord
crediting to Tenant (providing Tenant is not in default in the performance of
any of the terms, covenants and conditions of this Lease) any amount of
estimated payments made by Tenant in excess of Landlord's actual expenditures
for said Additional Rent items. Within thirty (30) days after receipt of
Landlord's reconciliation, Tenant shall have the right, at Tenant's sole
expense, to audit, at a mutually convenient time at Landlord's office,
Landlord's records relating to the foregoing expenses. Such audit must be
conducted by Tenant or an independent nationally recognized accounting firm that
is not being compensated by Tenant or other third party on a contingency fee
basis. Landlord shall be provided a complete copy of said audit at no expense to
Landlord. If such audit reveals that Landlord has overcharged Tenant, the amount
overcharged shall be credited to Tenant's account within thirty (30) days after
the audit is concluded.

     The respective obligations of Landlord and Tenant under this paragraph
shall survive the expiration or other termination of the term of this Lease, and
if the term hereof shall expire or shall otherwise terminate on a day other than
the last day of a calendar year, the actual Additional Rent incurred for the
calendar year in which the term hereof expires or otherwise terminates shall be
determined and settled on the basis of the statement of actual Additional Rent
for such calendar year and shall be prorated in the proportion which the number
of days in such calendar year preceding such expiration or termination bears to
365.

     E.   Fixed Management Fee. Beginning with the Commencement Date of the Term
of this Lease, Tenant shall pay to Landlord, in addition to the Basic Rent and
Additional Rent, a fixed monthly management fee ("Management Fee") equal to 3%
of the Basic Rent due for each month during the Lease Term.

     F.   Place of Payment of Rent and Additional Rent. All Basic Rent hereunder
and all payments hereunder for Additional Rent shall be paid to Landlord at the
office of Landlord at Peery/Arrillaga, File 1504, Box 60000, San Francisco, CA
94160 or to such other person or to such other place as Landlord may from time
to time designate in writing.

     G.   Security Deposit. Within three (3) days of delivery to Tenant of the
executed Lease, Tenant shall deposit with Landlord the sum of SIXTY SEVEN
THOUSAND THREE HUNDRED TWENTY AND NO/100 Dollars ($67,320.00). Said sum shall be
held by Landlord as a Security Deposit for the faithful performance by Tenant of
all of the terms, covenants, and conditions of this Lease to be kept and
performed by Tenant during the term hereof. If Tenant defaults with respect to
any provision of this Lease, including, but not limited to, the provisions
relating to the payment of rent and any of the monetary sums due herewith,
Landlord may (but shall not be required to) use, apply or retain all or any part
of this Security Deposit for the payment of any other amount which Landlord may
spend by reason of Tenant's default or to compensate Landlord for



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any other loss or damage which Landlord may suffer by reason of Tenant's
default. If any portion of said Deposit is so used or applied, Tenant shall,
within ten (10) days after written demand therefor, deposit cash with Landlord
in the amount sufficient to restore the Security Deposit to its original
amount. Tenant's failure to do so shall be a material breach of this Lease.
Landlord shall not be required to keep this Security Deposit separate from its
general funds, and Tenant shall not be entitled to interest on such Deposit. If
Tenant fully and faithfully performs every provision of this Lease to be
performed by it, the Security Deposit or any balance thereof shall be returned
to Tenant (or at Landlord's option, to the last assignee of Tenant's interest
hereunder) at the expiration of the Lease term and after Tenant has vacated the
Premises. In the event of termination of Landlord's interest in this Lease,
Landlord shall transfer said Deposit to Landlord's successor in interest
whereupon Tenant agrees to release Landlord from liability for the return of
such Deposit or the accounting therefor.

5. ACCEPTANCE AND SURRENDER OF PREMISES By entry hereunder, Tenant accepts the
Premises as being in good and sanitary order, condition and repair and accepts
the building and improvements included in the Premises in their present
condition and without representation or warranty by Landlord as to the
condition of such building or as to the use or occupancy which may be made
thereof. Any exceptions to the foregoing must be by written agreement executed
by Landlord and Tenant. Tenant agrees on the last day of the Lease term, or on
the sooner termination of this Lease, to surrender the Premises promptly and
peaceably to Landlord in good condition and repair (damage by Acts of God,
fire, normal wear and tear excepted), with all interior walls painted, or
cleaned so that they appear freshly painted, and repaired and replaced, if
damaged; all floors cleaned and waxed; all carpets cleaned and shampooed; all
broken, marred or nonconforming acoustical ceiling tiles replaced; all windows
washed; the airconditioning and heating systems serviced by a reputable and
licensed service firm and in good operating condition and repair; the plumbing
and electrical systems and lighting in good order and repair, including
replacement of any burned out or broken light bulbs or ballasts; the lawn and
shrubs in good condition including the replacement of any dead or damaged
plantings; the sidewalk, driveways and parking areas in good order, condition
and repair; together with all alterations, additions, and improvements which
may have been made in, to, or on the Premises (except moveable trade fixtures
installed at the expense of Tenant) except that Tenant shall ascertain from
Landlord within thirty (30) days before the end of the term of this Lease
whether Landlord desires to have the Premises or any part or parts thereof
restored to their condition and configuration as when the Premises were
delivered to Tenant and if Landlord shall so desire, then Tenant shall restore
said Premises or such part or parts thereof before the end of this Lease at
Tenant's sole cost and expense. Tenant, on or before the end of the term or
sooner termination of this Lease, shall remove all of Tenant's personal
property and trade fixtures from the Premises, and all property not so removed
on or before the end of the term or sooner termination of this Lease shall be
deemed abandoned by Tenant and title to same shall thereupon pass to Landlord
without compensation to Tenant. Landlord may, upon termination of this Lease,
remove all moveable furniture and equipment so abandoned by Tenant, at Tenant's
sole cost, and repair any damage caused by such removal at Tenant's sole cost.
If the Premises be not surrendered at the end of the term or sooner termination
of this Lease, Tenant shall indemnify Landlord against loss or liability
resulting from the delay by Tenant in so surrendering the Premises including,
without limitation, any claims made by any succeeding tenant founded on such
delay. Nothing contained herein shall be construed as an extension of the term
hereof or as a consent of Landlord to any holding over by Tenant. The voluntary
or other surrender of this Lease or the Premises by Tenant or a mutual
cancellation of this Lease shall not work as a merger and, at the option of
Landlord, shall either terminate all or any existing subleases or subtenancies
or operate as an assignment to Landlord of all or any such subleases or
subtenancies.

6. ALTERATIONS AND ADDITIONS Tenant shall not make, or suffer to be made, any
alteration or addition to the Premises, or any part thereof, without the written
consent, (which written consent will specify whether Landlord shall require
removal of said alterations and/or additions, provided Tenant requests such
determination from Landlord), of Landlord first had and obtained by Tenant
(such consent not to be unreasonably withheld), but at the cost of Tenant, and
any addition to, or alteration of, the Premises, except moveable furniture and
trade fixtures, shall at once become a part of the Premises and belong to
Landlord. Landlord reserves the right to approve all contractors and mechanics
proposed by Tenant to make such alterations and additions. Tenant shall retain
title to all moveable furniture and trade fixtures placed in the Premises. All
heating, lighting, electrical, air conditioning, floor to ceiling partitioning,
drapery, carpeting, and floor installations made by Tenant, together with all
property that has become an integral part of the Premises, shall not be deemed
trade fixtures. Tenant agrees that it will not proceed to make such alteration
or additions, without having obtained consent from Landlord to do so, and until
five (5) days from the receipt of such consent, in order that Landlord may post
appropriate notices to avoid any liability to contractors or material suppliers
for payment for Tenant's improvements. Tenant will at all times permit such
notices to be posted and to remain posted until the completion of work. Tenant
shall, if required by Landlord, secure at Tenant's own cost and expense, a
completion and lien indemnity bond, satisfactory to Landlord, for such work.
Tenant further covenants and agrees that any mechanic's lien filed against the
Premises 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 (10) days after the filing thereof, at the cost and expense of
Tenant. Any exceptions to the foregoing must be made in writing and executed by
both Landlord and Tenant.

7. TENANT MAINTENANCE Tenant shall, at its sole cost and expense, keep and
maintain the Premises (including appurtenances) and every part thereof in a
high standard of maintenance and repair, and in good and sanitary condition.
Tenant's maintenance and repair responsibilities herein referred to include,
but are not limited to, janitorization, plumbing systems within the non-common
areas of the Premises (such as water and drain lines, sinks), electrical
systems within the non-common areas of the Premises (such as outlets, lighting
fixtures, lamps, bulbs, tubes, ballasts), heating and airconditioning controls
within the non-common areas of the Premises (such as mixing boxes, thermostats,
time clocks, supply and return grills), all interior improvements within the
premises including but not limited to: wall coverings, window coverings,
acoustical ceilings, vinyl tile, carpeting, partitioning, doors (both interior
and exterior, including closing mechanisms, latches, locks), and all other
interior improvements of any nature whatsoever. Tenant agrees to be responsible
for wear and tear of the carpet caused by such rolling chairs if such wear and
tear exceeds that caused by normal foot traffic in surrounding areas. Areas of
excessive wear shall be replaced at Tenant's sole expense upon Lease
termination.

8. UTILITIES

9. TAXES

     A. As Additional Rent and in accordance with Paragraph 4D of this Lease,
Tenant shall pay to Landlord, or if Landlord so directs, directly to the Tax
Collector, all Real Property Taxes relating to the Premises. In the event the
Premises leased hereunder consist of only a portion of the entire tax parcel,
Tenant shall pay to Landlord Tenant's proportionate share of such real estate
taxes allocated to the leased Premises by square footage or other reasonable
basis as calculated and determined by Landlord. If the tax billing pertains
100% to the leased Premises, and Landlord chooses to have Tenant pay said real
estate taxes directly to the Tax Collector, then in such event it shall be the
responsibility of Tenant to obtain the tax and assessment bills and pay, prior
to delinquency, the applicable real property taxes and assessments pertaining
to the leased Premises, and failure to receive a bill for taxes and/or
assessments shall not provide a basis for cancellation of or nonresponsibility
for payment of penalties for nonpayment or late payment by Tenant. The term
"Real Property Taxes", as used herein, shall mean (i) all taxes, assessments,
levies and other charges of any kind or nature whatsoever, general and special,
foreseen and unforeseen (including all installments of principal and interest
required to pay any general or special assessments for public improvements and
any increases resulting from reassessments caused by any change in ownership of
the Premises) now or hereafter imposed by any governmental or
quasi-governmental authority or special district having the direct or indirect
power to tax or levy assessments, which are levied or assessed against, or with
respect to the value, occupancy or use of, all or any portion of the Premises
(as now constructed or as may at any time hereafter be constructed, altered, or
otherwise changed) or Landlord's interest therein; any improvements located
within the Premises (regardless of ownership); the fixtures, equipment and
other property of Landlord, real or personal, that are an integral part of and
located in the Premises; or parking areas, public utilities, or energy within
the Premises; (ii) all charges, levies or fees imposed by reason of
environmental regulation or other governmental control of the Premises; and
(iii) all costs and fees (including


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reasonable attorneys' fees) incurred by Landlord in reasonably contesting any
Real Property Tax and in negotiating with public authorities as to any Real
Property Tax. If at any time during the term of this Lease the taxation or
assessment of the Premises prevailing as of the commencement date of this Lease
shall be altered so that in lieu of or in addition to any Real Property Tax
described above there shall be levied, assessed or imposed (whether by reason
of a change in the method of taxation or assessment, creation of a new tax or
charge, or any other cause) an alternate or additional tax or charge (i) on the
value, use or occupancy of the Premises or Landlord's interest therein or (ii)
on or measured by the gross receipts, income or rentals from the Premises, on
Landlord's business of leasing the Premises, or computed in any manner with
respect to the operation of the Premises, then any such tax or charge, however,
designated, shall be included within the meaning of the term "Real Property
Taxes" for purposes of this Lease. If any Real Property Tax is based upon
property or rents unrelated to the Premises, then only that part of such Real
Property Tax that is fairly allocable to the Premises shall be included within
the meaning of the term "Real Property Taxes". Notwithstanding the foregoing,
the term "Real Property Taxes" shall not included estate, inheritance, gift or
franchise taxes of Landlord or the federal or state net income tax imposed on
Landlord's income from all sources.

     B.   Taxes on Tenant's Property  Tenant shall be liable for and shall pay
ten days before delinquency, 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 or if the assessed value of the Premises is increased by the
inclusion therein of a value placed upon such person property or trade fixtures
of Tenant and if Landlord, after written notice to Tenant, pays the taxes based
on 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, as the case may be, repay to Landlord the
taxes so levied against Landlord, or the proportion of such taxes resulting from
such increase in the assessment; provided that in any such event Tenant shall
have the right, in the name of Landlord and with Landlord's full cooperation, to
bring suit in any court of competent jurisdiction to recover the amount of such
taxes so paid under protest, and any amount so recovered shall belong to Tenant.

10.  LIABILITY INSURANCE  Tenant, at Tenant's expense, agrees to keep in force
during the term of this Lease a policy of commercial general liability
insurance with combined single limit coverage of not less than Two Million
Dollars ($2,000,000) per occurrence for bodily injury and property damage
occurring in, on or about the Premises, including parking and landscaped areas.
Such insurance shall be primary and noncontributory as respects any insurance
carried by Landlord. The policy or policies affecting such insurance shall name
Landlord as additional insureds, and shall insure any liability of Landlord,
contingent or otherwise, as respects acts or omissions of Tenant, its agents,
employees or invitees or otherwise by any conduct or transactions of any of
said persons in or about on concerning the Premises, including any failure of
Tenant to observe or perform any of its obligations hereunder; shall be issued
by an insurance company admitted to transact business in the State of
California; and shall provide that the insurance effected thereby shall not be
canceled, except upon thirty (30) days' prior written notice to landlord. A
certificate of insurance of said policy shall be delivered to Landlord. If,
during the term of this Lease, in the considered opinion of Landlord's Lender,
insurance advisor, or counsel, the amount of insurance described in this
Paragraph 10 is not adequate, Tenant agrees to increase said coverage to such
reasonable amount as Landlord's Lender, insurance advisor, or counsel shall deem
adequate.

11.  TENANT'S PERSONAL PROPERTY INSURANCE AND WORKMAN'S COMPENSATION INSURANCE
Tenant shall maintain a policy or policies of fire and property damage
insurance in "all risk" form with a sprinkler leakage endorsement insuring the
personal property, inventory, trade fixtures, and leasehold improvements within
the leased Premises for the full replacement value thereof. The proceeds from
any of such policies shall be used for the repair or replacement of such items
so insured.

     Tenant shall also maintain a policy or policies of workman's compensation
insurance and any other employee benefit insurance sufficient to comply with
all laws.

12.  PROPERTY INSURANCE  Landlord shall purchase and keep in force, and as
Additional Rent and in accordance with Paragraph 4D of this Lease, Tenant shall
pay to Landlord (or Landlord's agent if so directed by Landlord) Tenant's
proportionate share (allocated to the leased Premises by square footage or
other equitable basis as calculated and determined by Landlord) of the
deductibles on insurance claims and the cost of, policy or policies of
insurance covering loss or damage to the Premises (excluding routine
maintenance and repairs and incidental damage or destruction caused by
accidents or vandalism for which Tenant is responsible under Paragraph 7) in
the amount of the full replacement value thereof, providing protection against
those perils included within the classification of "all risks" insurance and
flood and/or earthquake insurance, if available, plus a policy of rental income
insurance in the amount of one hundred (100%) percent of twelve (12) months
Basic Rent, plus sums paid as Additional Rent. If such insurance cost is
increased due to Tenant's use of the Premises, Tenant agrees to pay to Landlord
the full cost of such increase. Tenant shall have no interest in nor any right
to the proceeds of any insurance procured by Landlord for the Premises.

     Landlord and Tenant do each hereby respectively release the other, to the
extent of insurance coverage of the releasing party, from any liability for
loss or damage caused by fire or any of the extended coverage casualties
included in the releasing party's insurance policies, irrespective of the cause
of such fire or casualty; provided, however, that if the insurance policy of
either releasing party prohibits such waiver, then this waiver shall not take
effect until consent to such waiver is obtained. If such waiver is so
prohibited, the insured party affected shall promptly notify the other party
thereof.

13.  INDEMNIFICATION  Landlord shall not be liable to Tenant and Tenant hereby
waives all claims against Landlord for any injury to or death of any person or
damage to or destruction of property in or about the Premises by or from any
cause whatsoever, including, without limitation, gas, fire, oil, electricity or
leakage of any character from the roof, walls, basement or other portion of the
Premises but excluding, however, the willful misconduct or negligence of
Landlord, its agents, servants, employees, invitees, or contractors of which
negligence Landlord has knowledge and reasonable time to correct. Except as to
injury to persons or damage to property to the extent arising from the willful
misconduct or the negligence of Landlord, its agents, servants, employees,
invitees, or contractors, Tenant shall hold Landlord harmless from and defend
Landlord against any and all expenses, including reasonable attorneys' fees, in
connection therewith, arising out of any injury to or death of any person or
damage to or destruction of property occurring in, on or about the Premises, or
any part thereof, from any cause whatsoever.

14.  COMPLIANCE  Tenant, at its sole cost and expense, shall promptly comply
with all laws, statutes, ordinances and governmental rules, regulations or
requirements now or hereafter in effect; with the requirements of any board of
fire underwriters or other similar body now or hereafter constituted; and with
any direction or occupancy certificate issued pursuant to law by any public
officer; provided, however, that no such failure shall be deemed a breach of the
provisions if Tenant, immediately upon notification, commences to remedy or
rectify said failure. The judgment of any court of competent jurisdiction or the
admission of Tenant in any action against Tenant, whether Landlord be a party
thereto or not, that Tenant has violated any such law, statute, ordinance or
governmental rule, regulation, requirement, direction or provision, shall be
conclusive of that fact as between Landlord and Tenant. Tenant shall, at its
sole cost and expense, comply with any and all requirements pertaining to said
Premises, of any insurance organization or company, necessary for the
maintenance of reasonable fire and public liability insurance covering
requirements pertaining to said Premises, of any insurance organization or
company, necessary for the maintenance of reasonable fire and public liability
insurance covering the Premises.

15.  LIENS  Tenant shall keep the Premises free from any liens arising out of
any work performed, materials furnished or obligation incurred by Tenant. In
the event that Tenant shall not, within ten (10) days following the imposition
of such lien, cause the same to be released of record, Landlord shall have, in
addition to all other remedies provided herein and by law, the right, but no
obligation, to cause the same to be released by such means as it shall deem
proper, including payment of the claim giving rise to such lien. All sums paid
by Landlord for such purpose, and all expenses incurred by it in connection
therewith, shall be payable to Landlord by Tenant on demand with interest at
the prime rate of interest as quoted by the Bank of America.

16.  ASSIGNMENT AND SUBLETTING  Tenant shall not assign, transfer, or
hypothecate the leasehold estate under this Lease, or any interest herein, and
shall not sublet the Premises, or any part thereof, or any right or privilege
appurtenant thereto, or suffer any other person or entity to occupy or use the
Premises, or any portion thereof, without, in each case, the prior written
consent of Landlord which consent will not be unreasonably withheld. As a
condition for granting this consent to any assignment, transfer, or subletting,
Landlord shall require Tenant to pay to Landlord, as Additional Rent, fifty
percent (50%) of all rent and/or additional consideration due Tenant from its
assignees, transferees, or subtenants in excess of the Rent payable by Tenant to
Landlord hereunder for the assigned, transferred and/or subleased space;
provided, however, that before sharing such excess rent, Tenant shall first be
entitled to recover from such excess rent the amount of any reasonable leasing
commissions paid by Tenant to third parties not affiliated with Tenant. Tenant
shall, by thirty (30) days written notice, advise Landlord of its intent to
assign or transfer Tenant's interest in the Lease or sublet the Premises or any
portion thereof for any part of the term hereof. Within thirty (30) days after
receipt of said written notice, Landlord may, in its sole discretion, elect to
terminate this Lease as to the portion of the Premises described in Tenant's
notice on the date specified in Tenant's notice by giving written notice of such
election to terminate. If no such notice to terminate is given to Tenant within
said thirty (30) day period, Tenant may proceed to locate an acceptable
sublessee, assignee, or other transferee for presentment to Landlord for
Landlord's approval, all in accordance with the terms, covenants, and conditions
of this paragraph 16. If Tenant intends to sublet the entire Premises and
Landlord elects to terminate this Lease, this Lease shall be terminated on the
date specified in Tenant's notice. If, however, this Lease shall terminate
pursuant to the foregoing with respect to less than all the Premises, the rent,
as defined and reserved hereinabove shall be adjusted on a pro rata basis to the
number of square feet retained by Tenant, and the Lease as so amended shall
continue in full force and effect. In the event Tenant is allowed to assign,
transfer or sublet the whole or any part of the Premises, with the prior written



                                  page 4 of 8
<PAGE>   5
consent of Landlord, no assignee, transferee or subtenant shall assign or
transfer this Lease, either in whole or in part, or sublet the whole or any part
of the Premises, without also having obtained the prior written consent of
Landlord. A consent of Landlord to one assignment, transfer, hypothecation,
subletting, occupation or use by any other person shall not release Tenant from
any of Tenant's obligations hereunder or be deemed to be a consent to any
subsequent similar or dissimilar assignment, transfer, hypothecation,
subletting, occupation or use by any other person. Any such assignment,
transfer, hypothecation, subletting, occupation or use without such consent
shall be void and shall constitute a breach of this Lease by Tenant and shall,
at the option of Landlord exercised by written notice to Tenant, terminate this
Lease. The leasehold estate under this Lease shall not, nor shall any interest
therein, be assignable for any purpose by operation of law without the written
consent of Landlord. As a condition to its consent, Landlord shall require
Tenant to pay all expenses in connection with the assignment, and Landlord shall
require Tenant's assignee or transferee (or other assignees or transferees) to
assume in writing all of the obligations under this Lease and for Tenant to
remain liable to Landlord under the Lease. Notwithstanding the above, in no
event will Landlord consent to a sub-sublease. See Paragraph 46

17. SUBORDINATION AND MORTGAGES  In the event Landlord's title or leasehold
interest is now or hereafter encumbered by a deed of trust, upon the interest of
Landlord in the land and buildings in which the demised Premises are located, to
secure a loan from a lender (hereinafter referred to as "Lender") to Landlord,
Tenant shall, at the request of Landlord or Lender, execute in writing an
agreement subordinating its rights under this Lease to the lien of such deed of
trust, or, if so requested, agreeing that the lien of Lender's deed of trust
shall be or remain subject and subordinate to the rights of Tenant under this
Lease. Notwithstanding any such subordination, Tenant's possession under this
Lease shall not be disturbed if Tenant is not in default and so long as Tenant
shall pay all rent and observe and perform all of the provisions set forth in
this Lease.

18. ENTRY BY LANDLORD  Landlord reserves, and shall at all reasonable times
after at least 24 hours notice (except in emergencies) have, the right to enter
the Premises to inspect them; to perform any services to be provided by Landlord
hereunder; to make repairs or provide any services to a contiguous tenant(s); to
submit the Premises to prospective purchasers, mortgagers or tenants; to post
notices of nonresponsibility; and to alter, improve or repair the Premises or
other parts of the building, all without abatement of rent, and may erect
scaffolding and other necessary structures in or through the Premises where
reasonably required by the character of the work to be performed; provided,
however that the business of Tenant shall be interfered with to the least extent
that is reasonably practical. Any entry to the Premises by Landlord for the
purposes provided for herein shall not under any circumstances be construed or
deemed to be a forcible or unlawful entry into or a detainer of the Premises or
an eviction, actual or constructive, of Tenant from the Premises or any portion
thereof.

19. BANKRUPTCY AND DEFAULT  The commencement of a bankruptcy action or
liquidation action or reorganization action or insolvency action or an
assignment of or by Tenant for the benefit of creditors, or any similar action
undertaken by Tenant, or the insolvency of Tenant, shall, at Landlord's option,
constitute a breach of this Lease by Tenant. If the trustee or receiver
appointed to serve during a bankruptcy, liquidation, reorganization, insolvency
or similar action elects to reject Tenant's unexpired Lease, the trustee or
receiver shall notify Landlord in writing of its election within thirty (30)
days after an order for relief in a liquidation action or within thirty (30)
days after the commencement of any action.

     Within thirty (30) days after court approval of the assumption of this
Lease, the trustee or receiver shall cure (or provide adequate assurance to the
reasonable satisfaction of Landlord that the trustee or receiver shall cure) any
and all previous defaults under the unexpired Lease and shall compensate
Landlord for all actual pecuniary loss and shall provide adequate assurance of
future performance under said Lease to the reasonable satisfaction of Landlord.
Adequate assurance of future performance, as used herein, includes, but shall
not be limited to: (i) assurance of source and payment of rent, and other
consideration due under this Lease; (ii) assurance that the assumption or
assignment of this Lease will not breach substantially any provision, such as
radius, location, use, or exclusivity provision, in any agreement relating to
the above described Premises.

     Nothing contained in this section shall affect the existing right of
Landlord to refuse to accept an assignment upon commencement of or in connection
with a bankruptcy, liquidation, reorganization or insolvency action or an
assignment of Tenant for the benefit of creditors or other similar act. Nothing
contained in this Lease shall be construed as giving or granting or creating an
equity in the demised Premises to Tenant. In no event shall the leasehold estate
under this Lease, or any interest therein, be assigned by voluntary or
involuntary bankruptcy proceeding without the prior written consent of Landlord.
In no event shall this Lease or any rights or privileges hereunder be an asset
of Tenant under any bankruptcy, insolvency or reorganization proceedings.

     The failure to perform or honor any covenant, condition or representation
made under this Lease shall constitute a default hereunder by Tenant upon
expiration of the appropriate grace period hereinafter provided. Tenant shall
have a period of five (5) days from the date of written notice from Landlord
within which to cure any default in the payment of rental or adjustment thereto.
Tenant shall have a period of thirty (30) days from the date of written notice
from Landlord within which to cure any other default under this Lease. Upon an
uncured default of this Lease by Tenant, Landlord shall have the following
rights and remedies in addition to any other rights or remedies available to
Landlord at law or in equity:

          (a) The rights and remedies provided for by California Civil Code
Section 1951.2, including but not limited to, recovery of 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 rental loss for the same period
that Tenant proves could be reasonably avoided, as computed pursuant to
subsection (b) of said Section 1951.2. Any proof by Tenant under subparagraphs
(2) and (3) of Section 1951.2 of the California Civil Code of the amount of
rental loss that could be reasonably avoided shall be made in the following
manner: Landlord and Tenant shall each select a licensed real estate broker in
the business of renting property of the same type and use as the Premises and in
the same geographic vicinity. Such two real estate brokers shall select a third
licensed real estate broker, and the three licensed real estate brokers so
selected shall determine the amount of the rental loss that could be reasonably
avoided from the balance of the term of this Lease after the time of award. The
decision of the majority of said licensed real estate brokers shall be final and
binding upon the parties hereto.

          (b) The rights and remedies provided by California Civil Code Section
which allows Landlord to continue the Lease in effect and to enforce all of its
rights and remedies under this Lease, including the right to recover rent as it
becomes due, for so long as Landlord does not terminate Tenant's right to
possession; acts of maintenance or preservation, efforts to relet the Premises,
or the appointment of a receiver upon Landlord's initiative to protect its
interest under this Lease shall not constitute a termination of Tenant's right
to possession.

          (c) The right to terminate this Lease by giving notice to Tenant in
accordance with applicable law.

          (d) To the extent permitted by law the right and power to enter the
Premises and remove therefrom all persons and property, to store such property
in a public warehouse or elsewhere at the cost of and for the account of Tenant,
and to sell such property and apply such proceeds therefrom pursuant to
applicable California law. Landlord may from time to time sublet the Premises or
any part thereof for such term or terms (which may extend beyond the term of
this Lease) and at such rent and such other terms as Landlord in its reasonable
sole discretion may deem advisable, with the right to make alterations and
repairs to the Premises. Upon each subletting, (i) Tenant shall be immediately
liable to pay Landlord, in addition to indebtedness other than rent due
hereunder, the reasonable cost of such subletting, including, but not limited
to, reasonable attorneys' fees, and any real estate commissions actually paid,
and the cost of such reasonable alterations and repairs incurred by Landlord and
the amount, if any, by which the rent hereunder for the period of such
subletting (to the extent such period does not exceed the term hereof) exceeds
the amount to be paid as rent for the Premises for such period or (ii) at the
option of Landlord, rents received from such subletting shall be applied first
to payment of indebtedness other than rent due hereunder from Tenant to
Landlord; second, to the payment of any costs of such subletting and of such
alterations and repairs; third to payment of rent due and unpaid hereunder; and
the residue, if any, shall be held by Landlord and applied in payment of future
rent as the same becomes due hereunder. If Tenant has been credited with any
rent to be received by such subletting under option (i) and such rent shall not
be promptly paid to Landlord by the subtenant(s), or if such rentals received
from such subletting under option (ii) during any month be less than that to be
paid during that month by Tenant hereunder, Tenant shall pay any such deficiency
to Landlord. Such deficiency shall be calculated and paid monthly. No taking
possession of the Premises by Landlord shall be construed as an election on its
part to terminate this Lease unless a written notice of such intention be given
to Tenant. Notwithstanding any such subletting without termination, Landlord may
at any time hereafter elect to terminate this Lease for such previous breach.

          (e) The right to have a receiver appointed for Tenant upon application
by Landlord, to take possession of the Premises and to apply any rental
collected from the Premises and to exercise all other rights and remedies
granted to Landlord pursuant to subparagraph d. above. See Paragraph 47

20. ABANDONMENT  Tenant shall not vacate or abandon the Premises at any time
during the term of this Lease, and if Tenant shall abandon, vacate or surrender
said Premises, or be dispossessed by the process of law, or otherwise, any
personal property belonging to Tenant and left on the Premises shall be deemed
to be abandoned, at the option of Landlord, except such property as may be
mortgaged to Landlord. See Paragraph 48

21. DESTRUCTION  In the event the Premises are destroyed in whole or in part
from any cause, except for routine maintenance and repairs and incidental


                                  page 5 of 8
<PAGE>   6


damage and destruction caused from vandalism and accidents for which Tenant is
responsible under Paragraph 7, Landlord may, at its option:

     (a)  Rebuild or restore the Premises to their condition prior to the damage
          or destruction, or

     (b)  Terminate this Lease. (providing that the Premises is damaged to the
          extent of 33 1/3% of the replacement cost)

     If Landlord does not give Tenant notice in writing within thirty (30) days
from the destruction of the Premises of its election to either rebuild and
restore them, or to terminate this Lease, Landlord shall be deemed to have
elected to rebuild or restore them, in which event Landlord agrees, at its
expense, except for any deductible, which is the responsibility of Tenant,
promptly to rebuild or restore the Premises to their condition prior to the
damage or destruction. Tenant shall be entitled to a reduction in rent while
such repair is being made in the proportion that the area of the Premises
rendered untenantable by such damage bears to the total area of the Premises, if
Landlord initially estimates that the rebuilding or restoration will exceed 180
days or if Landlord does not complete the rebuilding or restoration within one
hundred eighty (180) days following the date of destruction (such period of time
to be extended for delays caused by the fault or neglect of Tenant or because of
Acts of God, acts of public agencies, labor disputes, strikes, fires, freight
embargos, rainy or stormy weather, inability to obtain materials, supplies or
fuels, acts of contractors or subcontractors, or delay of the contractors or
subcontractors due to such causes or other contingencies beyond the control of
Landlord), then Tenant shall have the right to terminate this Lease by giving
fifteen (15) days prior written notice to Landlord. Notwithstanding anything
herein to the contrary, Landlord's obligation to rebuild or restore shall be
limited to the building and interior improvements constructed by Landlord as
they existed as of the commencement date of the Lease and shall not include
restoration of Tenant's trade fixtures, equipment, merchandise, or any
improvements, alterations or additions made by Tenant to the Premises, which
Tenant shall forthwith replace or fully repair at Tenant's sole cost and expense
provided this Lease is not cancelled according to the provisions above.

     Unless this Lease is terminated pursuant to the foregoing provisions, this
Lease shall remain in full force and effect. Tenant hereby expressly waives the
provisions of Section 1932, Subdivision 2, in Section 1933, Subdivision 4 of the
California Civil Code.

     In the event that the building in which the Premises are situated is
damaged or destroyed to the extent of not less than 33 1/3% of the replacement
cost thereof, Landlord may elect to terminate this Lease, whether the Premises
be injured or not. Notwithstanding anything to the contrary herein, Landlord may
terminate this Lease in the event of an uninsured event or if insurance proceeds
are insufficient to cover one hundred percent of the rebuilding costs net of the
deductible.

22.  EMINENT DOMAIN  If all or any part of the Premises shall be taken by any
public or quasi-public authority under the power of eminent domain or conveyance
in lieu thereof, this Lease shall terminate as to any portion of the Premises so
taken or conveyed on the date when title vests in the condemnor, and Landlord
shall be entitled to any and all payment, income, rent, award, or any interest
therein whatsoever which may be paid or made in connection with such taking or
conveyance, and Tenant shall have no claim against Landlord or otherwise for the
value of any unexpired term of this Lease. Notwithstanding the foregoing
paragraph, any compensation specifically awarded Tenant for loss of business,
Tenant's personal property, moving cost or loss of goodwill, shall be and remain
the property of Tenant.

     If any action or proceeding is commenced for such taking of the Premises or
any part thereof, or if Landlord is advised in writing by any entity or body
having the right or power of condemnation of its intention to condemn the
premises or any portion thereof, then Landlord shall have the right to terminate
this Lease by giving Tenant written notice thereof within sixty (60) days of the
date of receipt of said written advice, or commencement of said action or
proceeding, or taking conveyance, which termination shall take place as of the
first to occur of the last day of the calendar month next following the month in
which such notice is given or the date on which title to the Premises shall vest
in the condemnor.

     In the event of such a partial taking or conveyance of the Premises, if the
portion of the Premises taken or conveyed is so substantial that the Tenant can
no longer reasonably conduct its business, Tenant shall have the privilege of
terminating this Lease within sixty (60) days from the date of such taking or
conveyance, upon written notice to Landlord of its intention so to do, and upon
giving of such notice this Lease shall terminate on the last day of the calendar
month next following the month in which such notice is given, upon payment by
Tenant of the rent from the date of such taking or conveyance of the date of
termination.

     If a portion of the Premises be taken by condemnation or conveyance in lieu
thereof and neither Landlord nor Tenant shall terminate this Lease as provided
herein, this Lease shall continue in full force and effect as to the part of the
Premises not so taken or conveyed, and the rent herein shall be apportioned as
of the date of such taking or conveyance so that thereafter the rent to be paid
by Tenant shall be in the ratio that the area of the portion of the Premises not
so taken or conveyed bears to the total area of the Premises prior to such
taking.

23.  SALE OR CONVEYANCE BY LANDLORD  In the event of a sale or conveyance of the
Premises or any interest therein, by any owner of the reversion then
constituting Landlord, the transferor shall thereby be released from any further
liability upon any of the terms, covenants or conditions (express or implied)
herein contained in favor of Tenant, and in such event, insofar as such transfer
is concerned, Tenant agrees to look solely to the responsibility of the
successor in interest of such transferor in and to the Premises and this Lease.
This lease shall not be affected by any such sale or conveyance, and Tenant
agrees to attorn to the successor in interest of such transferor.

24.  ATTORNMENT TO LENDER OR THIRD PARTY  In the event the interest of Landlord
in the land and buildings in which the leased Premises are located (whether such
interest of Landlord is a fee title interest or a leasehold interest) is
encumbered by deed of trust, and such interest is acquired by the lender or any
third party through judicial foreclosure or by exercise of a power of sale at
private trustee's foreclosure sale, Tenant hereby agrees to attorn to the
purchaser at any such foreclosure sale and to recognize such purchaser as the
Landlord under this Lease. In the event the lien of the deed of trust securing
the loan from a Lender to Landlord is prior and paramount to the Lease, this
Lease shall nonetheless continue in full force and effect for the remainder of
the unexpired term hereof, at the same rental herein reserved and upon all the
other terms, conditions and covenants herein contained.

25.  HOLDING OVER  Any holding over by Tenant after expiration or other
termination of the term of this Lease with the written consent of Landlord
delivered to Tenant shall not constitute a renewal or extension of the Lease or
give Tenant any rights in or to the leased Premises except as expressly provided
in this Lease. Any holding over after the expiration or other termination of the
term of this Lease, with the consent of Landlord, shall be construed to be a
tenancy from month to month, on the same terms and conditions herein specified
insofar as applicable except that the monthly Basic Rent shall be increased to
an amount equal to one hundred fifty (150%) percent of the monthly Basic Rent
required during the last month of the Lease term.

26.  CERTIFICATE OF ESTOPPEL  Tenant shall at any time upon not less than ten
(10) days prior written notice from Landlord execute, acknowledge and deliver to
Landlord a statement in writing (i) certifying that this Lease is unmodified and
in full force and effect (or, if modified, stating the nature of such
modification and certifying that this Lease, as so modified, is in full force
and effect) and the date to which the rent and other charges are paid in
advance, if any, and (ii) acknowledging that there are not, to Tenant's
knowledge, any uncured defaults on the part of Landlord hereunder, or specifying
such defaults, if any, are claimed. Any such statement may be conclusively
relied upon by any prospective purchaser or encumbrancer of the Premises.
Tenant's failure to deliver such statement within such time shall be conclusive
upon Tenant that this Lease is in full force and effect, without modification
except as may be represented by Landlord; that there are no uncured defaults in
Landlord's performance, and that not more than one month's rent has been paid in
advance.

27.  CONSTRUCTION CHANGES  It is understood that the description of the Premises
and the location of ductwork, plumbing and other facilities therein are subject
to such minor changes as Landlord or Landlord's architect determines to be
desirable in the course of construction of the Premises, and no such changes
shall affect this Lease or entitle Tenant to any reduction of rent hereunder or
result in any liability of Landlord to Tenant. Landlord does not guarantee the
accuracy of any drawings supplied to Tenant and verification of the accuracy of
such drawings rests with Tenant.

28.  RIGHT OF LANDLORD TO PERFORM  All terms, covenants and conditions of this
Lease to be performed or observed by Tenant shall be performed or observed by
Tenant at Tenant's sole cost and expense and without any reduction of rent. If
Tenant shall fail to pay any sum of money, or other rent, required to be paid by
it hereunder and such failure shall continue for five (5) days after written
notice by Landlord, or shall fail to perform any other term or covenant
hereunder on its part to be performed, and such failure shall continue for
thirty (30) days after written notice thereof by Landlord, Landlord, without
waiving or releasing Tenant from any obligation of Tenant hereunder, may, but
shall not be obliged to, make any such payment or perform any such other term or
covenant on Tenant's part to be performed. All sums so paid by Landlord and all
necessary costs of such performance by Landlord together with interest thereon
at the rate of the prime rate of interest per annum as quoted by the Bank of
America from the date of such payment on performance by Landlord, shall be paid
(and Tenant covenants to make such payment) to Landlord on demand by Landlord,
and Landlord shall have (in addition to any other right or remedy of Landlord)
the same rights and remedies in the event of nonpayment by Tenant as in the case
of failure by Tenant in the payment of rent hereunder.

29.  ATTORNEYS' FEES

     A. In the event that either Landlord or Tenant should bring suit for the
possession of the Premises, for the recovery of any sum due under this Lease, or
because of the breach of any provision of this Lease, or for any other relief
against the other party hereunder, then all costs and expenses, including
reasonable attorneys' fees,

                                  page 6 of 8

<PAGE>   7
incurred by the prevailing party therein shall be paid by the other party, which
obligation on the part of the other party shall be deemed to have accrued on the
date of the commencement of such action and shall be enforceable whether or not
the action is prosecuted to judgment.

    B.  Should Landlord be named as a defendant in any suit brought against
Tenant in connection with or arising out of Tenant's occupancy hereunder,
Tenant shall pay to Landlord its costs and expenses incurred in such suit,
including a reasonable attorney's fee.

30. WAIVER The waiver by either party of the other party's failure to perform
or observe any term, covenant or condition herein contained to be performed or
observed by such waiving party shall not be deemed to be a waiver of such term,
covenant or condition or of any subsequent failure of the party failing to
perform or observe the same or any other such term, covenant or condition
therein contained, and no custom or practice which may develop between the
parties hereto during the term hereof shall be deemed a waiver of, or in any
way affect, the right of either party to insist upon performance and observance
by the other party in strict accordance with the terms hereof.

31. NOTICES All notices, demands, requests, advices or designations which may be
or are required to be given by either party to the other hereunder shall be in
writing. All notices, demands, requests, advices or designations by Landlord to
Tenant shall be sufficiently given, made or delivered if personally served on
Tenant by leaving the same at the Premises or if sent by United States certified
or registered mail, postage prepaid, addressed to Tenant at the Premises. All
notices, demands, requests, advices or designations by Tenant to Landlord shall
be sent by United States certified or registered mail, postage prepaid,
addressed to Landlord at its offices at Peery/Arrillaga, 2560 Mission College
Blvd., Suite 101, Santa Clara, CA 95054. Each notice, request, demand, advice or
designation referred to in this paragraph shall be deemed received on the date
of the personal service or, mailing thereof in the manner herein provided, as
the case may be.

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

33. DEFAULT BY LANDLORD Landlord shall not be in default unless Landlord fails
to perform obligations required of Landlord within a reasonable time, but in no
event earlier than (30) days after written notice by Tenant to Landlord and to
the holder of any first mortgage or deed of trust covering the Premises whose
name and address shall have heretofore been furnished to Tenant in writing,
specifying wherein Landlord has failed to perform such obligations; provided,
however, that if the nature of Landlord's obligations is such that more than
thirty (30) days are required for performance, then Landlord shall not be in
default if Landlord commences performance within such thirty (30) day period and
thereafter diligently prosecutes the same to completion.

34. CORPORATE AUTHORITY If Tenant is a corporation (or a partnership), each
individual executing this Lease on behalf of said corporation (or partnership)
represents and warrants that he is duly authorized to execute and deliver this
Lease on behalf of said corporation (or partnership) in accordance with the
by-laws of said corporation (or partnership in accordance with the partnership
agreement) and that this Lease is binding upon said corporation (or partnership)
in accordance with its terms. If Tenant is a corporation, Tenant shall, within
thirty (30) days after execution of this Lease, deliver to Landlord a certified
copy of the resolution of the Board of Directors of said corporation authorizing
or ratifying the execution of this Lease.

35.

36. LIMITATION OF 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 hereunder by Landlord:

    (a) the sole and exclusive remedy shall be against Landlord's interest in
the Premises leased herein;

    (b) no partner of Landlord shall be sued or named as a party in any suit or
action (except as may be necessary to secure jurisdiction of the partnership);

    (c) no service of process shall be made against any partner of Landlord
(except as may be necessary to secure jurisdiction of the partnership);

    (d) no partner of Landlord shall be required to answer or otherwise plead to
any service of process;

    (e) no judgment will be taken against any partner of Landlord;

    (f) any judgment taken against any partner of Landlord may be vacated and
set aside at any time without hearing;

    (g) no writ of execution will ever by levied against the assets of any
partner of Landlord;

    (h) these covenants and agreements are enforceable both by Landlord and also
by any partner of Landlord.

    Tenant agrees that each of the foregoing covenants and agreements shall be
applicable to any covenant or agreement either expressly contained in this Lease
or imposed by statute or at common law.

37. SIGNS No sign, placard, picture, advertisement, name or notice shall be
inscribed, displayed or printed or affixed on or to any part of the outside of
the Premises or any exterior windows of the Premises without the written consent
of Landlord first had and obtained and Landlord shall have the right to remove
any such sign, placard, picture, advertisement, name or notice without notice to
and at the expense of Tenant. If Tenant is allowed to print or affix or in any
way place a sign in, on, or about the Premises, upon expiration or other sooner
termination of this Lease, Tenant at Tenant's sole cost and expense shall both
remove such sign and repair all damage in such a manner as to restore all
aspects of the appearance of the Premises to the condition prior to the
placement of said sign.

    All approved signs or lettering on outside doors shall be printed, painted,
affixed or inscribed at the expense of Tenant by a person approved of by
Landlord.

    Tenant shall not place anything or allow anything to be placed near the
glass of any window, door partition or wall which may appear unsightly from
outside the Premises.

38. MISCELLANEOUS AND GENERAL PROVISIONS

    A. Use of Building Name. Tenant shall not, without the written consent of
Landlord, use the name of the building for any purpose other than as the address
of the business conducted by Tenant in the Premises.

                                  page 7 of 8
<PAGE>   8
     B. Choice of Law; Severability. This Lease shall in all respects be
governed by and construed in accordance with the laws of the State of
California. If any provision of this Lease shall be invalid, unenforceable or
ineffective for any reason whatsoever, all other provisions hereof shall be and
remain in full force and effect.

     C. Definition of Terms. The term "Premises" includes the space leased
hereby and any improvements now or hereafter installed therein or attached
thereto. The term "Landlord" or any pronoun used in place thereof includes the
plural as well as the singular and the successors and assigns of Landlord. The
term "Tenant" or any pronoun used in place thereof includes the plural as well
as the singular and individuals, firms, associations, partnerships and
corporations, and their and each of their respective heirs, executors,
administrators, successors and permitted assigns, according to the context
hereof, and the provisions of this Lease shall inure to the benefit of and bind
such heirs, executors, administrators, successors and permitted assigns.

     The term "person" includes the plural as well as the singular and
individuals, firms, associations, partnerships and corporations. Words used in
any gender include other genders. If there be more than one Tenant the
obligations of Tenant hereunder are joint and several. The paragraph headings of
this Lease are for convenience of reference only and shall have no effect upon
the construction or interpretation of any provision hereof.

     D. Time of Essence. Time is of the essence of this Lease and of each and
all of its provisions.

     E. Quitclaim. At the expiration or earlier termination of this Lease,
Tenant shall execute, acknowledge and deliver to Landlord, within ten (10) days
after written demand from Landlord to Tenant, any quitclaim deed or other
document required by any reputable title company, licensed to operate in the
State of California, to remove the cloud or encumbrance created by this Lease
from the real property of which Tenant's Premises are a part.

     F. Incorporation of Prior Agreements; Amendments. This instrument along
with any exhibits and attachments hereto constitutes the entire agreement
between Landlord and Tenant relative to the Premises and this agreement and the
exhibits and attachments may be altered, amended or revoked only by an
instrument in writing signed by both Landlord and Tenant. Landlord and Tenant
agree hereby that all prior or contemporaneous oral agreements between and among
themselves and their agents or representatives relative to the leasing of the
Premises are merged in or revoked by this agreement.

     G. Recording. Neither Landlord nor Tenant shall record this Lease or a
short form memorandum hereof without the consent of the other.

     H. Amendments for Financing. Tenant further agrees to execute any
amendments required by a lender to enable Landlord to obtain financing, so long
as Tenant's rights hereunder are not substantially affected.

     I. Additional Paragraphs. Paragraphs 39 through 54 are added hereto and are
included as a part of this lease.

     J. Clauses, Plats and Riders. Clauses, plats and riders, if any, signed by
Landlord and Tenant and endorsed on or affixed to this Lease are a part hereof.

     K. Diminution of Light, Air or View. Tenant covenants and agrees that no
diminution or shutting off of light, air or view by any structure which may be
hereafter erected (whether or not by Landlord) shall in any way affect his
Lease, entitle Tenant to any reduction of rent hereunder or result in any
liability of Landlord to Tenant.

   IN WITNESS WHEREOF, Landlord and Tenant have executed and delivered this
Lease as of the day and year last written below.

LANDLORD:                             TENANT:

JOHN ARRILLAGA SURVIVOR'S TRUST       SMITHKLINE BEECHAM CORPORATION
                                      a Pennsylvania corporation

By /s/ JOHN ARRILLAGA                 By /s/ GEORGE POSTE
   ----------------------------          ---------------------------------------
   John Arrillaga, Trustee               Dr. George Poste, Chief Science Officer

Date:          8/19/97                Date: 14 August 1997
      -------------------------             ------------------------------------

RICHARD T. PEERY SEPARATE PROPERTY TRUST

By /s/ RICHARD T. PEERY
   -------------------------------------
   Richard T. Peery, Trustee

Date:            8/22/97
      ----------------------------------


                                  page 8 of 8
<PAGE>   9

Paragraphs 39 through 54 to Lease Agreement dated June 26, 1997, By and between
the John Arrillaga Survivor's Trust and the Richard T. Peery Separate Property
Trust, as Landlord, and SMITHKLINE BEECHAM CORPORATION, a Pennsylvania
corporation, as Tenant for 30,600 Plus Square Feet of Space Located at
3233 Scott Blvd., Suite 102, Santa Clara, California.

39. BASIC RENT: In accordance with Paragraph 4A herein, the total aggregate sum
of THREE MILLION EIGHT HUNDRED FIFTY FIVE THOUSAND SIX HUNDRED AND NO/100
DOLLARS ($3,855,600.00), shall be payable as follows:

       For the period of August 15, 1997 through September 30, 1997, no Basic
Rent will be due; however, Tenant will be responsible for all Additional Rent
expenses as outlined in Paragraph 4D from the Commencement Date of the Lease.

       On October 1, 1997, the sum of SIXTY ONE THOUSAND TWO HUNDRED AND NO/100
DOLLARS ($61,200.00) shall be due, and a like sum due on the first day of each
month thereafter, through and including September 1, 1998.

       On October 1, 1998, the sum of SIXTY TWO THOUSAND SEVEN HUNDRED THIRTY
AND NO/100 DOLLARS ($62,730.00) shall be due, and a like sum due on the first
day of each month thereafter, through and including September 1, 1999.

       On October 1, 1999, the sum of SIXTY FOUR THOUSAND TWO HUNDRED SIXTY AND
NO/100 DOLLARS ($64,260.00) shall be due, and a like sum due on the first day of
each month thereafter, through and including September 1, 2000.

       On October 1, 2000, the sum of SIXTY FIVE THOUSAND SEVEN HUNDRED NINETY
AND NO/100 DOLLARS ($65,790.00) shall be due, and a like sum due on the first
day of each month thereafter, through and including September 1, 2001.

       On October 1, 2001, the sum of SIXTY SEVEN THOUSAND THREE HUNDRED TWENTY
AND NO/100 DOLLARS ($67,320.00) shall be due, and a like sum due on the first
day of each month thereafter, through and including September 1, 2002; or until
the entire aggregate sum of THREE MILLION EIGHT HUNDRED FIFTY FIVE THOUSAND SIX
HUNDRED AND NO/100 DOLLARS ($3,855,600.00) has been paid.

40. "AS-IS" BASIS: Except as provided in Paragraphs 42 and 53, it is hereby
agreed that the Premises leased hereunder is leased strictly on an "as-is" basis
and in its present condition, and in the configuration as shown on Exhibit B
attached hereto, and by reference made a part hereof. Except as noted herein, it
is specifically agreed between the parties that Landlord shall not be required
to make, nor be responsible for any cost, in connection with any repair,
restoration, and/or improvement to the Premises in order for this Lease to
commence, or thereafter, throughout the Term of this Lease. Notwithstanding
anything to the contrary within this Lease, Landlord makes no warranty or
representation of any kind or nature whatsoever as to the condition or repair of
the Premises, nor as to the use or occupancy which may be made thereof.

41. RULES AND REGULATIONS AND COMMON AREA: Subject to the terms and conditions
of this Lease and such Rules and Regulations as Landlord may from time to time
prescribe, Tenant and Tenant's employees, invitees and customers shall, in
common with other occupants of the Parcel/Building in which the premises are
located, and their respective employees, invitees and customers, and others
entitled to the use thereof, have the non-exclusive right to use the access
roads, parking areas, and facilities provided and designated by Landlord for the
general use and convenience of the occupants of the Parcel/Building in which the
Premises are located, which areas and facilities are referred to herein as
"Common Area". This right shall terminate upon the termination of this Lease.
Landlord reserves the right from time to time to make changes in the shape,
size, location, amount and extent of Common Area. Landlord further reserves the
right to promulgate such reasonable rules and regulations relating to the use of
the Common Area, and any part or parts thereof, as Landlord may deem appropriate
for the best interests of the occupants of the Parcel/Building. Such Rules and
Regulations may be amended by Landlord from time to time, with or without
advance notice, and all amendments shall be effective upon delivery of a copy
to Tenant. Landlord shall not be responsible to Tenant for the non-performance
by any other tenant or occupant of the Parcel/Building of any of said Rules
and Regulations.



                                     Page 9
<PAGE>   10

Landlord shall operate, manage and maintain the Common Area. The manner in which
the common area shall be maintained and the expenditures for such maintenance
shall be at the discretion of Landlord.

42. EXPENSES OF OPERATION, MANAGEMENT, AND MAINTENANCE OF THE COMMON AREAS OF
THE PARCEL AND BUILDING IN WHICH THE PREMISES ARE LOCATED: As Additional Rent
and in accordance with Paragraph 4D of this Lease, Tenant shall pay to Landlord
Tenant's proportionate share (calculated on a square footage or other equitable
basis as calculated by landlord) of all expenses of operation, management,
maintenance and repair of the Common Areas of the Parcel including, but not
limited to, license, permit, and inspection fees; security; utility charges
associated with exterior landscaping and lighting (including water and sewer
charges); all charges incurred in the maintenance and replacement of landscaped
areas, lakes, parking lots and paved areas (including repairs, replacement,
resealing and restriping), sidewalks, driveways, maintenance, repair and
replacement of all fixtures and electrical, mechanical and plumbing systems;
supplies, materials, equipment and tools; the cost of capital expenditures which
have the effect of reducing operating expenses, provided, however, that in the
event Landlord makes such capital improvements, Landlord may amortize its
investment in said improvements (together with interest at the rate of fifteen
(15%) percent per annum on the unamortized balance) as an operating expense in
accordance with standard accounting practices, provided, that such amortization
is not at a rate greater than the anticipated savings in the operating expenses.
Notwithstanding the above, Landlord agrees to repair (as necessary), reseal and
restripe the parking lot, at no cost to Tenant, prior to October 1, 1997.

As Additional Rent and in accordance with Paragraph 4D of this Lease, Tenant
shall pay its proportionate share (calculated on a square footage or other
equitable basis as calculated by Landlord) of the cost of operation (including
common utilities), management, maintenance, and repair of the building
(including structural and common areas such as lobbies, restrooms, janitor's
closets, hallways, elevators, mechanical and telephone rooms, stairwells,
entrances, spaces above the ceilings and amoritization of said common areas) in
which the Premises are located. The maintenance items herein referred to
include, but are not limited to, all windows, window frames, plate glass,
glazing, truck doors, main plumbing systems of the building (such as water drain
lines, sinks, toilets, faucets, drains, showers and water fountains), main
electrical systems (such as panels and conduits), heating and air-conditioning
systems (such as compressors, fans, air handlers, ducts, boilers, heaters),
structural elements and exterior surfaces of the building; store fronts, roof,
downspouts, building common area interiors (such as wall coverings, window
coverings, floor coverings and partitioning), ceilings, building exterior doors,
skylights (if any), automatic fire extinguishing systems, and elevators (if
any); license, permit and inspection fees; security, supplies, materials,
equipment and tools; the cost of capital expenditures which have the effect of
reducing operating expenses, provided, however, that in the event Landlord makes
such capital improvements, Landlord may amortize its investment in said
improvements (together with interest at the rate of fifteen (15%) percent per
annum on the unamoritized balance) as an operating expense in accordance with
standard accounting practices, provided, that such amortization is not at a rate
greater than the anticipated savings in the operating expenses. Tenant hereby
waives all rights hereunder, and benefits of, subsection 1 of Section 1932 and
Sections 1941 and 1942 of the California Civil Code and under any similar law,
statute or ordinance now or hereafter in effect.

"Additional Rent" as used herein shall not include Landlord's debt repayments;
interest on charges, expenses directly or indirectly incurred by Landlord for
the benefit of any other tenant; cost for the installation of partitioning or
any other tenant improvements; cost of attracting tenants; depreciation;
interest; or executive salaries.

43. UTILITIES OF THE BUILDING IN WHICH THE PREMISES ARE LOCATED: As Additional
Rent and in accordance with Paragraph 4D of this Lease Tenant shall pay its
proportionate share (calculated on a square footage or other equitable basis as
calculated by Landlord) of the cost of all utility charges such as water, gas,
electricity, (telephone, telex and other electronic communications service, if
applicable) sewer service, waste pick-up and any other utilities, materials or
services furnished directly to the building in which the Premises are located,
including, without limitation, any temporary or permanent utility surcharge or
other exactions whether or not hereinafter imposed.

Landlord shall not be liable for and Tenant shall not be entitled to any
abatement or reduction of rent by reason of any interruption or failure of
utility services to the Premises when such interruption or failure is caused by
accident, breakage, repair, strikes, lockouts, or other labor



                                    Page 10
<PAGE>   11

disturbances or labor disputes of any nature, or by any other cause, similar or
dissimilar, beyond the reasonable control of Landlord.

Provided that Tenant is not in default in the performance or observance of any
of the terms, covenants or conditions of this Lease to be performed or observed
by it, Landlord shall furnish to the Premises between the hours of 8:00 am and
6:00 pm, Mondays through Fridays (holidays excepted) and subject to the rules
and regulations of the Common Area hereinbefore referred to, reasonable
quantities of water, gas and electricity suitable for the intended use of the
Premises and heat and air-conditioning required in Landlord's judgment for the
comfortable use and occupation of the Premises for such purposes. Tenant agrees
that at all times it will cooperate fully with Landlord and abide by all
regulations and requirements that Landlord may prescribe for the proper
functioning and protection of the building heating, ventilating and
air-conditioning systems. Whenever heat generating machines, equipment, or any
other devices (including exhaust fans) are used in the Premises by Tenant which
affect the temperature or otherwise maintained by the air-conditioning system,
Landlord shall have the right to install supplementary air-conditioning units in
the Premises and the cost thereof, including the cost of installation and the
cost of operation and maintenance thereof, shall be paid by Tenant to Landlord
upon demand by Landlord. Tenant will not, without the written consent of
Landlord, use any apparatus or device in the Premises (including, without
limitation), electronic data processing machines or machines using current in
excess of 110 Volts which will in any way increase the amount of electricity,
gas, water or airconditioning usually furnished or supplied to premises being
used as general office space, or connect with electric current (except through
existing electrical outlets in the Premises), or with gas or water pipes any
apparatus or device for the purposes of using electric current, gas, or water.
If Tenant shall require water, gas, or electric current in excess of that
usually furnished or supplied to premises being used as general office space,
Tenant shall first obtain the written consent of Landlord, which consent shall
not be unreasonably withheld and Landlord may cause an electric current, gas or
water meter to be installed in the Premises in order to measure the amount of
electric current, gas or water consumed for any such excess use. The cost of any
such meter and of the installation, maintenance and repair thereof, all charges
for such excess water, gas and electric current consumed (as shown by such
meters and at the rates then charged by the furnishing public utility); and any
additional expense incurred by Landlord in keeping account of electric current,
gas, or water so consumed shall be paid by Tenant, and Tenant agrees to pay
Landlord therefor promptly upon demand by Landlord.

44. PARKING: Tenant shall have the right to the nonexclusive use of one hundred
seventy eight (178) parking spaces in the common parking area of the building.
Tenant agrees that Tenant, Tenant's employees, agents, representatives, and/or
invitees shall not use parking spaces in excess of said 178 parking spaces
allocated to Tenant hereunder. Landlord shall have the right, at Landlord's sole
discretion, to specifically designate the location of Tenant's parking spaces
within the common parking area of the building in the event of a dispute among
the tenants occupying the building referred to herein, in which event Tenant
agrees that Tenant, Tenant's employees, agents, representatives and/or invitees
shall not use any parking spaces other than those parking spaces specifically
designated by Landlord for Tenant's use. Said parking spaces, if specifically
designated by Landlord to Tenant, may be relocated by Landlord at any time, and
from time to time. Landlord reserves the right, at Landlord's sole discretion,
to rescind any specific designation of parking spaces, thereby returning
Tenant's parking spaces to the common parking area. Landlord shall give Tenant
written notice of any change in Tenant's parking spaces. Tenant shall not, at
any time, park, or permit to be parked, any trucks or vehicles adjacent to the
loading area so as to interfere in any way with the use of such areas, nor shall
Tenant, at any time, park or permit the parking of Tenant's trucks and other
vehicles or the trucks and vehicles of Tenant's suppliers or others, in any
portion of the common areas not designated by Landlord for such use by Tenant.
Tenant shall not park nor permit to be parked, any inoperative vehicles or
equipment on any portion of the common parking area or other common areas of the
building. Tenant agrees to assume responsibility for compliance by its employees
with the parking provision contained herein. If Tenant or its employees park in
other than designated parking areas, then Landlord may charge Tenant, as an
additional charge, and Tenant agrees to pay Ten Dollars ($10.00) per day for
each day or partial day each such vehicle is parking in any area other than that
designated. Tenant hereby authorizes Landlord, at Tenant's sole expense, to tow
away from the building any vehicle belonging to Tenant or Tenant's employees
parked in violation of these provisions, or to attach violation stickers or
notices to such vehicles. Tenant shall use the parking area for vehicle parking
only and shall not use the parking areas for storage.



                                    Page 11
<PAGE>   12

45. ASSESSMENT CREDITS: The demised property herein may be subject to a special
assessment levied by the City of Santa Clara as part of an Improvement District.
As a part of said special assessment proceedings (if any), additional bonds were
or may be sold and assessments were or may be levied to provide for construction
contingencies and reserve funds. Interest shall be earned on such funds created
for contingencies and on reserve funds which will be credited for the benefit of
said assessment district. To the extent surpluses are created in said district
through unused contingency funds, interest earnings or reserve funds, such
surpluses shall be deemed the property of Landlord. Notwithstanding that such
surpluses may be credited on assessments otherwise due against the Leased
Premises, Tenant shall pay to Landlord, as additional rent if, and at the time
of any such credit of surpluses, an amount equal to all such surpluses so
credited. For example: if (i) the property is subject to an annual assessment of
$1,000.00, and (ii) a surplus of $200.00 is credited towards the current year's
assessment which reduces the assessment amount shown on the property tax bill
from $1,000.00 to $800.00, Tenant shall, upon receipt of notice from Landlord,
pay to Landlord said $200.00 credit as Additional Rent.

46. ASSIGNMENT AND SUBLETTING (CONTINUED):

       A. In addition to and notwithstanding anything to the contrary in
Paragraph 16 of this Lease, Landlord hereby agrees to consent to Tenant's
assigning or subletting said Lease to: (i) any parent or subsidiary corporation,
or corporation with which Tenant merges or consolidates provided that the net
worth of said parent or subsidiary corporation, or said corporation has a net
worth equal to or greater than the net worth of Tenant (a) at the time of Lease
execution or (b) at the time of such assignment, merger, or consolidation
(whichever is greater); or (ii) any third party or entity to whom Tenant sells
all or substantially all of its assets; provided, that the net worth of the
resulting or acquiring corporation has a net worth after the merger,
consolidation or acquisition equal to or greater than the net worth of Tenant
(a) at the time of Lease execution or (b) at the time of such merger,
consolidation or acquisition (whichever is greater); or (iii) any parent company
of Tenant; or (iv) any limited liability company in which Tenant (or an
affiliate of Tenant) has a membership interest of more than 35%, including any
corporation formed by the event of such limited liability company converting its
form of organization from a limited liability company to a corporation. No such
assignment or subletting will release the Tenant from its liability and
responsibility under this Lease to the extent Tenant continues in existence
following such transaction; provided that Tenant shall have no liability or
responsibility under this Lease with respect to any period after the expiration
of the Term as defined in Paragraph 2 (or the expiration of the Extended Term in
the event that the option granted in Paragraph 52 hereof is exercised).
Notwithstanding the above, Tenant shall be required to (a) give Landlord written
notice prior to such assignment or subletting to any party as described in (i),
(ii), (iii) or (iv) above, and (b) execute Landlord's consent document prepared
by Landlord reflecting the assignment or subletting.

       B. Any and all sublease agreement(s) between Tenant and any and all
subtenant(s) (which agreements must be consented to by Landlord, pursuant to the
requirements of this Lease) shall contain the following language:

                     "If Landlord and Tenant jointly and voluntarily elect, for
       any reason whatsoever, to terminate the Master Lease prior to the
       scheduled Master Lease termination date, then this Sublease (if then
       still in effect) shall terminate concurrently with the termination of the
       Master Lease. Subtenant expressly acknowledges and agrees that (1) the
       voluntary termination of the Master Lease by Landlord and Tenant and the
       resulting termination of this Sublease shall not give Subtenant any right
       or power to make any legal or equitable claim against Landlord, including
       without limitation any claim for interference with contract or
       interference with prospective economic advantage, and (2) Subtenant
       hereby waives any and all rights it may have under law or at equity
       against Landlord to challenge such an early termination of the Sublease,
       and unconditionally releases and relieves Landlord, and its officers,
       directors, employees and agents, from any and all claims, demands, and/or
       causes of action whatsoever (collectively, "Claims"), whether such
       matters are known or unknown, latent or apparent, suspected or
       unsuspected, foreseeable or unforeseeable, which Subtenant may have
       arising out of or in connection with any such early termination of this
       Sublease. Subtenant knowingly and intentionally waives any and all
       protection which is or may be given by Section 1542 of the California
       Civil which provides as follows: "A general release does not extend to
       claims which the creditor does not know or suspect to exist in his favor
       at the time of executing the release, which if known by him must have
       materially affected his settlement with



                                    Page 12
<PAGE>   13

       debtor.

              The term of this Sublease is therefore subject to early
       termination. Subtenant's initials here below evidence (a) Subtenant's
       consideration of and agreement to this early termination provision, (b)
       Subtenant's acknowledgment that, in determining the net benefits to be
       derived by Subtenant under the terms of this Sublease, Subtenant has
       anticipated the potential for early termination, and (c) Subtenant's
       agreement to the general waiver and release of Claims above.

               Initials:                  Initials:
                        ------------               --------
                         Subtenant                  Tenant

47. BANKRUPTCY AND DEFAULT: Paragraph 19 is modified to provide that with
respect to non-monetary defaults not involving Tenant's failure to pay Basic
Rent or Additional Rent, Tenant shall not be in default of any non-monetary
obligation if (i) more than thirty (30) days is required to cure such
non-monetary default, and (ii) Tenant commences cure of such default as soon as
reasonably practicable after receiving written notice of such default from
Landlord and thereafter continuously and with due diligence prosecutes such cure
to completion.

48. ABANDONMENT: Paragraph 20 is modified to provide that Tenant shall not be in
default under the Lease if it leaves all or any part of Premises vacant so long
as (i) Tenant is performing all of its other obligations under the Lease
including the obligation to pay Basic Rent and Additional Rent (ii) Tenant
provides on-site security during normal business hours for those parts of the
Premises left vacant, (iii) such vacancy does not materially and adversely
affect the validity or coverage of any policy of insurance carried by Landlord
with respect to the Premises, and (iv) the utilities and heating and ventilation
system are operated and maintained to the extent necessary to prevent damage to
the Premises or its systems.

49. HAZARDOUS MATERIALS: Landlord and Tenant agree as follows with respect to
the existence or use of "Hazardous Materials" (as defined herein) on, in, under
or about the Premises and real property located beneath said Premises and the
common areas of the Parcel, which includes the entire parcel of land on which
the Premises are located as shown in Green on Exhibit A attached hereto
(hereinafter collectively referred to as the "Property"):

       A. As used herein, the term "Hazardous Materials" shall mean any
material, waste, chemical, mixture or byproduct which is or hereafter is
defined, listed or designated under Environmental Laws (defined below) as a
pollutant, or as a contaminant, or as a toxic or hazardous substance, waste or
material, or any other unwholesome, hazardous, toxic, biohazardous, or
radioactive material, waste, chemical, mixture or byproduct, or which is listed,
regulated or restricted by any Environmental Law (including, without limitation,
petroleum hydrocarbons or any distillates or derivatives or fractions thereof,
polychlorinated biphenyls, or asbestos). As used herein, the term "Environmental
Laws" shall mean any applicable Federal, State of California or local government
law (including common law), statute, regulation, rule, ordinance, permit,
license, order, requirement, agreement, or approval, or any determination,
judgment, directive, or order of any executive or judicial authority at any
level of Federal, State of California or local government (whether now existing
or subsequently adopted or promulgated) relating to pollution or the protection
of the environment, ecology, natural resources, or public health and safety.

       B. Tenant shall obtain Landlord's written consent, which may be withheld
in Landlord's discretion, prior to the occurrence of any Tenant's Hazardous
Materials Activities (defined below); provided, however, that Landlord's consent
shall not be required for normal use in compliance with applicable Environmental
Laws of customary household and office supplies (Tenant shall first provide
Landlord with a list of said materials use), such as mild cleaners, lubricants
and copier toner. As used herein, the term "Tenant's Hazardous Materials
Activities" shall mean any and all use, handling, generation, storage, disposal,
treatment, transportation, release, discharge, or emission of any Hazardous
Materials on, in, beneath, to, from, at or about the Property, in connection
with Tenant's use of the Property, or by Tenant or any of Tenant's agents,
employees, contractors, vendors, invitees, visitors or its future subtenants or
assignees. Tenant agrees that any and all Tenant's Hazardous Materials
Activities shall be conducted in strict, full compliance with applicable
Environmental Laws at Tenant's expense, and shall result in



                                    Page 13
<PAGE>   14

any contamination of the Property or the environment. Tenant agrees to provide
Landlord with prompt written notice of any spill or release of Hazardous
Materials at the Property during the term of the Lease of which Tenant becomes
aware, and further agrees to provide Landlord with prompt written notice of any
violation of Environmental Laws in connection with Tenant's Hazardous Materials
Activities of which Tenant becomes aware. If Tenant's Hazardous Materials
Activities involve Hazardous Materials other than normal use of customary
household and office supplies, Tenant also agrees at Tenant's expense: (i) to
install such Hazardous Materials monitoring, storage and containment devices as
Landlord reasonably deems necessary (Landlord shall have no obligation to
evaluate the need for any such installation or to require any such
installation); (ii) provide Landlord with a written inventory of such Hazardous
Materials, including an update of same each year upon the anniversary date of
the Commencement Date of the Lease ("Anniversary Date"); and (iii) on each
Anniversary Date, to retain a qualified environmental consultant, acceptable to
Landlord, to evaluate whether Tenant is in compliance with all applicable
Environmental Laws with respect to Tenant's Hazardous Materials Activities.
Tenant, at its expense, shall submit to Landlord a report from such
environmental consultant which discusses the environmental consultant's findings
within two (2) months of each Anniversary Date. Tenant, at its expense, shall
promptly undertake and complete any and all steps necessary, and in full
compliance with applicable Environmental Laws, to fully correct any and all
problems or deficiencies identified by the environmental consultant, and
promptly provide Landlord with documentation of all such corrections.

       C. Prior to termination or expiration of the Lease, Tenant, at its
expense, shall (i) properly remove from the Property all Hazardous Materials
which come to be located at the Property in connection with Tenant's Hazardous
Materials Activities, and (ii) fully comply with and complete all facility
closure requirements of applicable Environmental Laws regarding Tenant's
Hazardous Materials Activities, including but not limited to (x) properly
restoring and repairing the Property to the extent damaged by such closure
activities, and (y) obtaining from the local Fire Department or other
appropriate governmental authority with jurisdiction a written concurrence that
closure has been completed in compliance with applicable Environmental Laws.
Tenant shall promptly provide Landlord with copies of any claims, notices, work
plans, data and reports prepared, received or submitted in connection with any
such closure activities.

       D. To the best of Landlord's knowledge, the Property, including all
underlying land and groundwater, are free from contamination by toxic or
otherwise hazardous substances; however, Landlord shall have no obligation to
investigate.

       E. If Landlord, in its sole discretion, believes that the Property has
become contaminated as a result of Tenant's Hazardous Materials Activities,
Landlord in addition to any other rights it may have under this Lease or under
Environmental Laws or other laws, may enter upon the Property and conduct
inspection, sampling and analysis, including but not limited to obtaining and
analyzing samples of soil and groundwater, for the purpose of determining the
nature and extent of such contamination. Tenant shall promptly reimburse
Landlord for the costs of such an investigation, including but not limited to
reasonable attorneys' fees Landlord incurs with respect to such investigation,
that discloses Hazardous Materials contamination for which Tenant is liable
under this Lease. Except as may be required of Tenant by applicable
Environmental Laws, Tenant shall not perform any sampling, testing, or drilling
to identify the presence of any Hazardous Materials at the Property, without
Landlord's prior written consent which may be withheld in Landlord's discretion.
Tenant shall promptly provide Landlord with copies of any claims, notices, work
plans, data and reports prepared, received or submitted in connection with any
sampling, testing or drilling performed pursuant to the preceding sentence.

       F. Tenant shall indemnify, defend (with legal counsel acceptable to
Landlord, whose consent shall not unreasonably be withheld) and hold harmless
Landlord, its employees, assigns, successors, successors-in-interest, agents and
representatives from and against any and all claims (including but not limited
to third party claims from a private party or a government authority),
liabilities, obligations, losses, causes of action, demands, governmental
proceedings or directives, fines, penalties, expenses, costs (including but not
limited to reasonable attorneys', consultants' and other experts' fees and
costs), and damages, which arise from or relate to: (i) Tenant's Hazardous
Materials Activities; (ii) any Hazardous Materials contamination caused by
Tenant prior to the Commencement Date of the Lease; or (iii) the breach of any
obligation of Tenant under this Paragraph 49 (collectively, "Tenant's
Environmental Indemnification"). Tenant's Environmental Indemnification shall
include but is not limited to the obligation to promptly and fully reimburse
Landlord for losses in or reductions to rental income, and diminution in fair
market value of the Property. Tenant's Environmental Indemnification shall
further include but is not limited to the obligation to diligently and properly
implement to completion, at Tenant's expense any and all



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<PAGE>   15

environmental investigation, removal, remediation, monitoring, reporting,
closure activities, or other environmental response action (collectively,
"Response Actions"). Tenant shall promptly provide Landlord with copies of any
claims, notices, work plans, data and reports prepared, received or submitted in
connection with any Response Actions.

It is agreed that the Tenant's responsibilities related to Hazardous Materials
will survive the expiration or termination of this Lease and that Landlord may
obtain specific performance of Tenant's responsibilities under this Paragraph
49.

50. CONSENT: Whenever the consent of one party to the other is required
hereunder, such consent shall not be unreasonably withheld.

51. AUTHORITY TO EXECUTE. The parties executing this Lease Agreement hereby
warrant and represent that they are properly authorized to execute this Lease
Agreement and bind the parties on behalf of whom they execute this Lease
Agreement and to all of the terms, covenants and conditions of this Lease
Agreement as they relate to the respective parties hereto.

52. OPTION TO EXTEND LEASE FOR FIVE (5) YEARS: Landlord hereby grants to Tenant
an Option to Extend this Lease Agreement for an additional five (5) year period
(the "Extended Term") upon the following terms and conditions;

       A. Tenant shall give Landlord written notice of Tenant's exercise of this
Option to Extend not later than six (6) months prior to the scheduled Lease
Termination Date, which Termination Date is currently projected to be September
30, 2002, in which event the Lease shall be considered extended for an
additional five (5) years subject to the Basic Rental set forth below and with:
(i) the Rent to be determined pursuant to Paragraph B below and the terms and
conditions subject to amendment by Landlord (Landlord, in its sole and absolute
discretion, may, but is not required to, incorporate its current Lease
provisions that are standard in Landlord's leases as of the date of Tenant's
exercise of its Option to Extend) and (ii) this Paragraph 52 deleted. In the
event that Tenant fails to timely exercise Tenant's option as set forth herein
in writing, Tenant shall have no further Option to Extend this Lease, and this
Lease shall continue in full force and effect for the full remaining term
hereof, absent this Paragraph 52.

       B. The following summarizes the Basic Monthly Rental and the related per
square foot charge by period under the Lease Agreement that would be applied to
the Extended Term:

<TABLE>
<CAPTION>
                                                           Monthly
               Period                  PSF Rate            Basic Rental
               ------                  --------            ------------
<S>                                    <C>                 <C>
               10101/02-09/30/03        $2.25              $68,850.00
               10/01/03-09/30/04        $2.30              $70,380.00
               10/01/04-09/30/05        $2.35              $71,910.00
               10/01/05-09/30/06        $2.40              $73,440.00
               10/01/06-09/30/07        $2.45              $74,970.00
</TABLE>

       C. The option rights of Tenant under this Paragraph 52, and the Extended
Term thereunder, are granted for Tenant's personal benefit and may not be
assigned or transferred by Tenant (except as provided for in Paragraph 46),
either voluntarily or by operation of law, in any manner whatsoever. In the
event that Landlord consents to a sublease or assignment under Paragraph 16, the
option granted herein and any Extended Term thereunder shall be void and of no
force and effect, whether or not Tenant shall have purported to exercise such
option prior to such assignment or sublease.

       D. Notwithstanding anything to the contrary in this Paragraph 52, this
Option to Extend is automatically forfeited by Tenant (without notice from
Landlord) in the event Tenant is, at any time during the Term of this Lease, in
default of said Lease and if Tenant does not completely cure said default within
five days for a monetary default and thirty days for a nonmonetary default. In
the event said Option to Extend is forfeited as stated herein, Tenant shall have
no further Option to Extend this Lease.

       E. INCREASED SECURITY DEPOSIT: In the event the term of Tenant's Lease is



                                    Page 15
<PAGE>   16

extended pursuant to this Paragraph 52, Tenant's Security Deposit shall be
increased to equal the Basic Rental due for the last month of the extended term
(i.e. $74,970.00).

53. PUNCH LIST: In addition to and notwithstanding anything to the contrary in
Paragraphs 5 and 40 of this Lease, Tenant shall have thirty (30) days after the
Commencement Date to provide Landlord with a written "punch list" pertaining to
material defects in the Building and in the interior improvements constructed by
Landlord for Tenant. As soon as reasonably possible thereafter, Landlord, or one
of Landlord's representatives (if so approved by Landlord), and Tenant shall
conduct a joint walk-through of the Premises (if Landlord so requires), and
inspect such Tenant Improvements, using their best efforts to agree on the
incomplete or defective construction related to the Tenant Improvements
installed by Landlord. After such inspection has been completed, Landlord shall
prepare, and both parties shall sign, a list of all "punch list" items which the
parties reasonably agree are (i) to be corrected by Landlord (but which shall
exclude any damage or defects caused by Tenant, its employees, agents or parties
Tenant has contracted with to work on the Premises) or (ii) if said defects
and/or damaged items) are not material, Landlord may elect, in its sole and
absolute discretion, not to repair such item(s), but to acknowledge in written
form the defect and/or damaged item(s); in which case, notwithstanding anything
to the contrary in said Lease Paragraph 5 ("Acceptance and Surrender"), Tenant
shall not be responsible upon Lease Termination to repair said items) so noted
by Landlord. Landlord shall have thirty (30) days thereafter (or longer if
necessary, provided Landlord is diligently pursuing the completion of the same)
to complete, at Landlord's expense, the "punch list" items without the
Commencement Date of the Lease and Tenant's obligation to pay Rental thereunder
being affected. Notwithstanding the foregoing, a crack in the foundation, or
exterior walls or any other defect in the structure or Building that does not
endanger the structural integrity of the building, or which is not life
threatening, shall not be considered material, nor shall Landlord be responsible
for repair of same. This Paragraph shall be of no force and effect if Tenant
shall fail to give any such notice to Landlord within thirty (30) days after the
Commencement Date of this Lease.

54. LANDLORD'S RIGHT TO ENTER: Notwithstanding the provisions of Paragraph 18,
(i) except in the event of an emergency, Landlord shall give Tenant twenty-four
(24) hours notice prior to entering the Premises, agrees to comply with any
reasonable safety and/or security regulations imposed by Tenant with respect to
such entry, and shall only enter the Premises when accompanied by Tenant or its
agent (so long as Tenant makes itself reasonably available for this purpose),
and (ii) Landlord may install "for lease" signs relating to the Premises only
during the last 180 days of the Lease term. Landlord agrees to use its
reasonable, good faith efforts such that any entry by Landlord, and Landlord's
agents, employees, contractors and invitees shall be performed in a manner with
as minimal interference as possible with Tenant's business at the Premises.
Subject to the foregoing, Tenant agrees to cooperate with Landlord and
Landlord's agents, employees and contractors so that responsibilities of
Landlord under the Lease can be fulfilled in a reasonable manner during normal
business hours so that no extraordinary costs are incurred by Landlord.
<PAGE>   17






                                  [SITE PLAN]






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                                  [FLOOR PLAN]