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                                 STANDARD FORM LEASE
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PARTIES: This Lease, executed in duplicate at Cupertino, California, on May 19,
1998, by and between Berg & Berg Enterprises, Inc., a California Corporation,
and Mission West Properties, a California corporation, hereinafter called
respectively Lessor and Lessee, without regard to number or gender.


USE: WITNESSETH: That Lessor hereby leases to Lessee, and Lessee hires from
Lessor, for the purpose of conducting therein office, research and development,
light manufacturing, and warehouse activities, and any other legal activity; and
for no other purpose without obtaining the prior written consent of Lessor.

PREMISES: The real property with appurtenances as shown on Exhibit A (the
"Premises") situated in the City of Cupertino, County of Santa Clara, State of
California, and more particularly described as follows:

     Lessee's portion of the Premises is 3,200 square feet of an approximately
     7,500 square foot building, including all improvements thereto, as shown on
     Exhibit A.1 including the right to use its pro-rata share of the parking
     spaces located at the Premises.  The address for the leased portion of the
     Premises is 10050 Bandley Drive, Cupertino,  California.  Lessee's pro-rata
     share of the building is approximately 42.67%.

TERM: The term shall be for thirty-six  (36) months unless extended pursuant to
Section 35 of this Lease (the "Lease Term"), commencing on April 1, 1998 and
ending thirty-six (36) months thereafter.

RENT: Base rent shall be payable in monthly installments as follows: 




                                   Base rent      Estimated CAC*      Total
                                   ---------      --------------      -----
                                                            
     Months 1 through 36           $5,600            $1,120*         $6,720



* CAC charges to be adjusted per Common Area Charges Section below.

Base rent and CAC as scheduled above shall be payable in advance on or before
the first day of each calendar month during the Lease Term.  The term "Rent," as
used herein, shall be deemed to be and to mean the base monthly rent and all
other sums required to be paid by Lessee pursuant to the terms of this Lease. 
Rent shall be paid in lawful money of the United States of America, without
offset or deduction, and shall be paid to Lessor at such place or places as may
be designated from time to time by Lessor.  Rent for any period less than a
calendar month shall be a pro rata portion of the monthly installment.  Upon
execution of this Lease, Lessee shall deposit with Lessor the first month's
rent.

SECURITY DEPOSIT: Lessee shall deposit with Lessor the sum of Six Thousand Seven
Hundred Twenty Dollars ($6,720) (the "Security Deposit").  The Security Deposit
shall be held by Lessor as security for the faithful performance by Lessee of
all of the terms, covenants, and conditions of this Lease applicable to Lessee. 
If Lessee commits a default as provided for herein, including but not limited to
a default with respect to the provisions contained herein relating to the
condition of the Premises, Lessor may (but shall not be required to) use, apply
or retain all or any part of the Security Deposit for the payment of any amount
which Lessor may spend by reason of default by Lessee.  If any portion of the
Security Deposit is so used or applied, Lessee shall, within ten days after
written demand therefor, deposit cash with Lessor in an amount sufficient to
restore the Security Deposit to its original amount.  Lessee's failure to do so
shall be a default by Lessee.  Any attempt by Lessee to transfer or encumber its
interest in the Security Deposit shall be null and void.  Upon execution of this
Lease, Lessee shall deposit with Lessor the Security Deposit.   Notwithstanding
the above, Lessor agrees to waive the requirement for Lessee to make a security
deposit provided Lessee's shareholder's equity exceeds $7.5 million.  If at any
time during this Lease, Lessee's shareholder's equity is less than $7.5 million,
Lessee shall deposit with Lessor the Security Deposit referenced above within
ten days after the issuance of Lessee's financial statements indicating the
reduction in shareholder's equity below $7.5 million.  If Lessee fails to make
the Security Deposit as required, Lessee shall be deemed to be in default per
Section 14.1 (a) of this Lease.

COMMON AREA CHARGES: Lessee shall pay to Lessor, as additional Rent, an amount
equal to Lessee's pro-rate share of the total common area charges of the
Premises as defined below (the common area charges for the Premises is referred
to herein as ("CAC")).  Lessee shall pay to Lessor as Rent, on or before the
first day of each calendar month during the Lease Term, subject to adjustment
and reconciliation as provided hereinbelow, the sum of One Thousand One Hundred
Twenty Dollars ($1,120), said sum representing Lessee's estimated monthly
payment of Lessee's percentage share of CAC.  It is understood and agreed that 



Lessee's obligation under this paragraph shall be prorated to reflect the
Commencement Date and the end of the Lease Term.  Upon execution of this Lease,
Lessee shall deposit with Lessor the first month's estimated CAC.

Lessee's estimated monthly payment of CAC payable by Lessee during the calendar
year in which the Lease commences is set forth above.  At or prior to the
commencement of each succeeding calendar year term (or as soon as practical
thereafter), Lessor shall provide Lessee with Lessee's estimated monthly payment
for CAC which Lessee shall pay to Lessor as Rent.  Within 120 days of the end of
the calendar year and the end of the Lease Term, Lessor shall provide Lessee a
statement of actual CAC incurred including capital reserves for the preceding
year or other applicable period in the case of a termination year.  If such
statement shows that Lessee has paid less than its actual percentage, then
Lessee shall on demand pay to Lessor the amount of such deficiency.   If such
statement shows that Lessee has paid more than its actual percentage, then
Lessor shall, at its option, promptly refund such excess to Lessee or credit the
amount thereof to the Rent next becoming due from Lessee.  Lessor reserves the
right to revise any estimate of CAC if the actual or projected CAC show an
increase or decrease in excess of 10% from an earlier estimate for the same
period.  In such event, Lessor shall provide a revised estimate to Lessee,
together with an explanation of the reasons therefor, and Lessee shall revise
its monthly payments accordingly.  Lessor's and Lessee's obligation with respect
to adjustments at the end of the Lease Term or earlier expiration of this Lease
shall survive the Lease Term or earlier expiration.

As used in this Lease, CAC shall include but is not limited to: (i) items as
specified in Sections 5(b), 6, 12, 16 and 31; (ii) all costs and expenses
including but not limited to supplies, materials, equipment and tools used or
required in connection with the operation and maintenance of the Premises; (iii)
licenses, permits and inspection fees;  (iv) all other costs incurred by Lessor
in maintaining and operating the Premises; (v) all reserves for capital
replacements and government regulations imposed on the Premises not related to
Lessee's use and occupancy of the Premises; and (vi) an amount equal to five
percent (5%) of the aggregate of all CAC, as compensation for Lessor's
accounting and processing services.  Lessee shall have the right to review the
basis and computation analysis used to derive the CAC applicable to this Lease
annually.

LATE CHARGES: Lessee hereby acknowledges that a late payment made by Lessee to
Lessor of Rent and other sums due hereunder will cause Lessor to incur costs not
contemplated by this Lease, the exact amount of which will be extremely
difficult to ascertain.  Such costs include, but are not limited to, processing
and accounting charges, and late charges, which may be imposed on Lessor
according to the terms of any mortgage or trust deed covering the Premises. 
Accordingly, if any installment of Rent or any other sum due from Lessee is not
received by Lessor or Lessor's designee within ten (10) days after such amount
is due, Lessee shall pay to Lessor a late charge equal to five (5%) percent of
such overdue amount.  The parties hereby agree that such late charge represents
a fair and reasonable estimate of the costs Lessor will incur by reason of late
payments made by Lessee.  Acceptance of such late charges by Lessor shall in no
event constitute a waiver of Lessee's default with respect to such overdue
amount, nor shall it prevent Lessor from exercising any of the other rights and
remedies granted hereunder.

QUIET ENJOYMENT: Lessor covenants and agrees with Lessee that upon Lessee paying
Rent and performing its covenants and conditions under this Lease, Lessee shall
and may peaceably and quietly have, hold and enjoy the Premises for the Lease
Term, subject, however, to the rights reserved by Lessor hereunder.

OFFICE/OVERHEAD SHARING:  It is understood and acknowledged that the Premises
described herein shall be utilized for the business operations of both Lessor
and Lessee.  Lessee shall pay for or reimbursement Lessor for its prorata share,
to be determined by Lessor on an equitable basis, of all building and
operational expenses related to the use of the office, the equipment in the
office, office supplies, personnel costs, management costs, and any other costs
necessary for the operation of a professional management organization at the
Premises.  In addition, Lessee and Lessor shall each be responsible for the
exclusive costs of their own organization.  The primary purpose of this
arrangement is to utilize the existing resources of Lessor and its staff to
benefit Lessee at a reasonable cost to Lessee.  Notwithstanding the above,
Lessee's obligation under this Lease, including base rent, CAC, and
office/overhead sharing shall not exceed Fifteen Thousand Dollars ($15,400) per
month during the first thirty-six months of the Lease Term.    

IT IS FURTHER MUTUALLY AGREED BETWEEN THE PARTIES AS FOLLOWS:
1.   POSSESSION: Possession shall be deemed tendered and the term shall commence
effective April 1, 1998.

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2.1 ACCEPTANCE OF PREMISES AND COVENANTS TO SURRENDER: Lessee accepts the
Premises in an "AS IS" condition and "AS IS" state of repair, subject to
Lessor's representation that the Premises are in good order and repair, and
comply with all requirements for occupancy as of the Commencement Date.  Lessee
agrees on the last day of the Lease Term, or on the sooner termination of this
Lease, to surrender the Premises to Lessor in Good Condition and Repair.  Good
Condition and Repair ("Good Condition and Repair") shall not mean original
condition, but shall mean that the Premises are in a commercially acceptable
condition suitable for occupancy by a reasonable lessee.  The interior walls of
all office and warehouse areas, the floors of all office and warehouse areas,
all suspended ceilings and any carpeting are to be cleaned and in Good Condition
and Repair. Lessee, on or before the end of the Lease Term or sooner termination
of this Lease, shall remove all its personal property and trade fixtures from
the Premises, and all such property not so removed shall be deemed to be
abandoned by Lessee.  Lessee shall reimburse Lessor for all disposition costs
incurred by Lessor relative to Lessee's abandoned property.  If the Premises are
not surrendered at the end of the Lease Term or earlier termination of this
Lease, Lessee shall indemnify Lessor against loss or liability resulting from
any delay caused by Lessee in surrendering the Premises including, without
limitation, any claims made by any succeeding Lessee founded on such delay.  

3. USES PROHIBITED: Lessee shall not commit, or suffer to be committed, any
waste upon the Premises, or any nuisance, or other act or thing which may
disturb the quiet enjoyment of any other tenant in or around the buildings in
which the subject Premises are located or allow any sale by auction upon the
Premises, or allow the Premises to be used for any improper, immoral, unlawful
or objectionable purpose, or place any loads upon the floor, walls, or ceiling
which may endanger the structure, or use any machinery or apparatus which will
in any manner vibrate or shake the Premises or the building of which it is a
part, or place any harmful liquids in the drainage system of the building.  No
waste materials or refuse shall be dumped upon or permitted to remain upon any
part of the Premises outside of the building proper.  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 on any
portion of the Premises outside of the building structure, unless approved by
the local, state federal or other applicable governing authority.  Lessor
consents to Lessee's use of materials which are incidental to the normal,
day-to-day operations of any office user, such as copier fluids, cleaning
materials, etc., but this does not relieve Lessee of any of its obligations not
to contaminate the Premises and related real property or violate any Hazardous
Materials Laws.

4. ALTERATIONS AND ADDITIONS: Lessee shall not make, or suffer to be made, any
alteration or addition to said Premises, or any part thereof, without the
express, advance written consent of Lessor; any addition or alteration to said
Premises, except movable furniture and trade fixtures, shall become at once a
part of the realty and belong to Lessor at the end of the Lease Term or earlier
termination of this Lease.  Alterations and additions which are not deemed as
trade fixtures shall include HVAC systems, lighting systems, electrical systems,
partitioning, carpeting, or any other installation which has become an integral
part of the Premises.  Lessee agrees that it will not proceed to make such
alterations or additions until all required government permits have been
obtained and after having obtained consent from Lessor to do so, until five (5)
days from the receipt of such consent, so that Lessor may post appropriate
notices to avoid any liability to contractors or material suppliers for payment
for Lessee's improvements.  Lessee shall at all times permit such notices to be
posted and to remain posted until the completion of work.  At the end of the
Lease Term or earlier termination of this Lease, Lessee shall remove and shall
be required to remove its special tenant improvements, all related equipment,
and any additions or alterations installed by Lessee at or during the Lease Term
and Lessee shall return the Premises to the condition that existed before the
installation of the tenant improvements.  Notwithstanding the above, Lessor
agrees to allow any reasonable alterations and improvements and will use its
best efforts to notify Lessee at the time of approval if such improvements or
alterations are to be removed at the end of the Lease Term  or earlier
termination of this Lease.

5. MAINTENANCE OF PREMISES: 
     (a) Lessee shall at its sole cost and expense keep, repair, and maintain
     the interior of the Premises, including, but not limited to, all lighting
     systems, temperature control systems, and plumbing systems in Good
     Condition and Repair, including any required replacements.  Lessee shall
     maintain all wall surfaces and floor coverings in Good Condition and
     Repair, free of holes, gouges, or defacements and provide interior and
     exterior window washing as needed.  

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     (b) Lessor shall, at Lessee's expense, keep, repair, and maintain in Good
     Condition and Repair including replacements (based on a pro-rata share of
     (i) costs based on square footage or (ii) costs directly related to
     Lessee's use of the Premises) the following, which shall be included in the
     monthly CAC:
          1. The exterior of the building, any appurtenances and every part
          thereof, including but not limited to, glazing, sidewalks, parking
          areas, electrical systems, HVAC systems,  roof membrane, and painting
          of exterior walls.  The parking lot to receive a finish coat every
          five to seven years.
          2. The HVAC by a service contract with a licensed air conditioning and
          heating contractor which contract shall provide for a minimum of
          quarterly maintenance of all air conditioning and heating equipment at
          the Premises including HVAC repairs or replacements which are either
          excluded from such service contract or any existing equipment
          warranties.
          3. The landscaping by a landscape contractor to water, maintain, trim
          and replace, when necessary, any shrubbery and landscaping at the
          Premises.
          4. The roof membrane by a service contract with a licensed reputable
          roofing contractor which contract shall provide for a minimum of
          semi-annual maintenance, cleaning of storm gutters, drains, removing
          of debris, and trimming overhanging trees, repair of the roof and
          application of a finish coat every five years to the building at the
          Premises.
          5. Exterior pest control.
          6. Fire monitoring services.

     (c) Lessee hereby waives any and all rights to make repairs at the expense
     of Lessor as provided in Section 1942 of the Civil Code of the State of
     California, and all rights provided for by Section 1941 of said Civil Code.

     (d) Lessor shall be responsible for the repair of any structural defects in
     the Premises including the roof structure (not membrane), exterior walls
     and foundation during the Lease Term.

6. INSURANCE:
     A) HAZARD INSURANCE: Lessee shall not use, or permit said Premises, or any
     part thereof, to be used, for any purpose other than that for which the
     Premises are hereby leased; and no use shall be made or permitted to be
     made of the Premises, nor acts done, which may cause a cancellation of any
     insurance policy covering the Premises, or any part thereof, nor shall
     Lessee sell or permit to be kept, used or sold, in or about said Premises,
     any article which may be prohibited by a fire and extended coverage
     insurance policy.  Lessee shall comply with any and all requirements,
     pertaining to said Premises, of any insurance organization or company,
     necessary for the maintenance of reasonable fire and extended coverage
     insurance, covering the Premises.  Lessor shall, at Lessee's sole cost and
     expense, purchase and keep in force fire and extended coverage insurance,
     covering loss or damage to the  Premises in an amount equal to the full
     replacement cost of the Premises, as determined by Lessor, with proceeds
     payable to Lessor.  In the event of a loss per the insurance provisions of
     this paragraph, Lessee shall be responsible for deductibles up to a maximum
     of $5,000 per occurrence.  Lessee acknowledges that the insurance
     referenced in this paragraph does not include coverage for Lessee's
     personal property.  

     B) LOSS OF RENTS INSURANCE: Lessor shall, at Lessee's sole cost and
     expense, purchase and maintain in full force and effect, a policy of rental
     loss insurance, in an amount equal to the amount of Rent payable by Lessee
     commencing on the date of loss for the next ensuing one (1) year, as
     reasonably determined by Lessor with proceeds payable to Lessor ("Loss of
     Rents Insurance"). 

     C) LIABILITY AND PROPERTY DAMAGE INSURANCE: Lessee, as a material part of
     the consideration to be rendered to Lessor, hereby waives all claims
     against Lessor and Lessor's Agents for damages to goods, wares and
     merchandise, and all other personal property in, upon, or about the
     Premises, and for injuries to persons in, upon, or about the Premises, from
     any cause arising at any time, and Lessee will hold Lessor and Lessor's
     Agents exempt and harmless from any damage or injury to any person, or to
     the goods, wares, and merchandise and all other personal property of any
     person, arising from the use or occupancy of the Premises by Lessee, or
     from the failure of Lessee to keep the Premises in Good Condition and
     Repair, as herein provided.  Lessee shall, at Lessee's sole cost and
     expense, purchase and keep in force a standard policy of commercial general
     liability insurance and property damage policy covering the Premises and
     all related areas insuring the 

PAGE 4


     Lessee  having a combined single limit for both bodily injury, death and
     property damage in an amount not less than five million dollars
     ($5,000,000.00) and Lessee's insurance shall be primary.  The limits of
     said insurance shall not, however, limit the liability of Lessee hereunder.
     Lessee shall, at its sole cost and expense, comply with all of the
     insurance requirements of all local, municipal, state and federal
     authorities now in force, or which may hereafter be in force, pertaining to
     Lessee's use and occupancy of the said Premises. 

     D) PERSONAL PROPERTY INSURANCE: Lessee shall obtain, at Lessee's sole cost
     and expense, a policy of fire and extended coverage insurance including
     coverage for direct physical loss special form, and a sprinkler leakage
     endorsement insuring the personal property of Lessee.  The proceeds from
     any personal property damage policy shall be payable to Lessee. 

All insurance policies required in 6 C) and 6 D) above shall: (i) provide for a
certificate of insurance evidencing the insurance required herein, being
deposited with Lessor ten (10) days prior to the Commencement Date, and upon
each renewal, such certificates shall be provided 30 days prior to the
expiration date of such coverage, (ii) be in a form reasonably satisfactory to
Lessor and shall provide the coverage required by Lessee in this Lease, (iii) be
carried with companies with a Best Rating of A+ minimum, (iv) specifically
provide that such policies shall not be subject to cancellation, reduction of
coverage, or other change except after 30 days prior written notice to Lessor,
(v) name Lessor, Lessor's lender, and any other party with an insurable interest
in the Premises as additional insureds by endorsement to policy, and (vi) shall
be primary.

Lessee agrees to pay to Lessor, as additional Rent, on demand, the full cost of
the insurance polices referenced in 6 A) and 6 B)  above as evidenced by
insurance billings to Lessor which shall be included in the CAC.  If Lessee does
not occupy the entire Premises, the insurance premiums shall be allocated to the
portion of the Premises occupied by Lessee on a pro-rata square footage or other
equitable basis, as determined by Lessor.  It is agreed that Lessee's obligation
under this paragraph shall be prorated to the reflect the Commencement Date and
the end of the Lease Term.

Lessor and Lessee hereby waive any rights each may have against the other
related to any loss or damage caused to Lessor or Lessee as the case may be, or
to the Premises or its contents, and which may arise from any risk generally
covered by fire and extended coverage insurance.  The parties shall provide that
their respective insurance policies insuring the property or the personal
property include a waiver of any right of subrogation which said insurance
company may have against Lessor or Lessee, as the case may be.

7. ABANDONMENT: Lessee shall not vacate or abandon the Premises at any time
during the Lease Term; and if Lessee shall abandon, vacate or surrender said
Premises, or be dispossessed by process of law, or otherwise, any personal
property belonging to Lessee and left on the Premises shall be deemed to be
abandoned, at the option of Lessor.  Notwithstanding the above, the Premises
shall not be considered vacated or abandoned if Lessee maintains the Premises in
Good Condition and Repair, provides security and is not in default.

8. FREE FROM LIENS: Lessee shall keep the subject Premises and the property in
which the subject Premises are situated, free from any and all liens including
but not limited to liens arising out of any work performed, materials furnished,
or obligations incurred by Lessee.  However, the Lessor shall allow Lessee to
contest a lien claim, so long as the claim is discharged prior to any
foreclosure proceeding being initiated against the property and provided Lessee
provides Lessor a bond if the lien exceeds $5,000.

9. COMPLIANCE WITH GOVERNMENTAL REGULATIONS: Lessee shall, at its sole cost and
expense, comply with all of the requirements of all local, municipal, state and
federal authorities now in force, or which may hereafter be in force, pertaining
to  the Premises, and shall faithfully observe in the use and occupancy of the
Premises all local and municipal ordinances and state and federal statutes now
in force or which may hereafter be in force. 

10. INTENTIONALLY OMITTED.

11. ADVERTISEMENTS AND SIGNS: Lessee shall not place or permit to be placed, in,
upon or about the Premises any unusual or extraordinary signs, or any signs not
approved by the city, local, state, federal or other applicable governing
authority. Lessee 

PAGE 5


shall not place, or permit to be placed upon the Premises, any signs,
advertisements or notices without the written consent of the Lessor, and such
consent shall not be unreasonably withheld.  A sign so placed on the Premises
shall be so placed upon the understanding and agreement that Lessee will remove
same at the end of the Lease Term or earlier termination of this Lease and
repair any damage or injury to the Premises caused thereby, and if not so
removed by Lessee, then Lessor may have the same removed at Lessee's expense.

12. UTILITIES: Lessee shall pay for all water, gas, heat, light, power,
telephone and other utilities supplied to the Premises which shall be included
in Lessee's monthly estimated CAC.  Any charges for sewer usage, PG&E and
telephone site service or related fees shall be the obligation of Lessee and
paid for by Lessee and shall be included in Lessee's monthly estimated CAC.  If
any such services are not separately metered to Lessee, Lessee shall pay a
reasonable proportion of all charges which are jointly metered, the
determination to be made by Lessor acting reasonably and on any equitable basis.
Lessor and Lessee agree that Lessor shall not be liable to Lessee for any
disruption in any of the utility services to the Premises.

13. ATTORNEY'S FEES: In case suit should be brought for the possession of the
Premises, for the recovery of any sum due hereunder, because of the breach of
any other covenant herein, or to enforce, protect, or establish any term,
conditions, or covenant of this Lease or the right of either party hereunder,
the losing party shall pay to the Prevailing Party reasonable attorney's fees
which shall be deemed to have accrued on the commencement of such action and
shall be enforceable whether or not such action is prosecuted to judgment.  The
term "Prevailing Party" shall mean the party that received substantially the
relief requested, whether by settlement, dismissal, summary judgment, judgment,
or otherwise.

14.1 DEFAULT: The occurrence of any of the following shall constitute a default
and breach of this Lease by Lessee: a) Any failure by Lessee to pay Rent or to
make any other payment required to be made by Lessee hereunder when due if not
cured within ten (10) days after written notice thereof by Lessor to Lessee; b)
The abandonment or vacation of the Premises by Lessee except as provided in
Section 7; c) A failure by Lessee to observe and perform any other provision of
this Lease to be observed or performed by Lessee, where such failure continues
for thirty days after written notice thereof by Lessor to Lessee; provided,
however, that if the nature of such default is such that the same cannot be
reasonably cured within such thirty (30) day period, Lessee shall not be deemed
to be in default if Lessee shall, within such period, commence such cure and
thereafter diligently prosecute the same to completion; d) The making by Lessee
of any general assignment for the benefit of creditors; the filing by or against
Lessee of a petition to have Lessee adjudged a bankrupt or of a petition for
reorganization or arrangement under any law relating to bankruptcy; e) the
appointment of a trustee or receiver to take possession of substantially all of
Lessee's assets or Lessee's interest in this Lease, or the attachment, execution
or other judicial seizure of substantially all of Lessee's assets located at the
Premises or of Lessee's interest in this Lease.

14.2 SURRENDER OF LEASE: In the event of any such default by Lessee, then in
addition to any other remedies available to Lessor at law or in equity, Lessor
shall have the immediate option to terminate this Lease before the end of the
Lease Term and all rights of Lessee hereunder, by giving written notice of such
intention to terminate.  In the event that Lessor terminates this Lease due to a
default of Lessee, then Lessor may recover from Lessee: a) the worth at the time
of award of any unpaid Rent which had been earned at the time of such
termination; plus b) the worth at the time of award of unpaid Rent which would
have been earned after termination until the time of award exceeding the amount
of such rental loss that the Lessee proves could have been reasonably avoided;
plus c) the worth at the time of award of the amount by which the unpaid Rent
for the balance of the Lease Term after the time of award exceeds the amount of
such rental loss that the Lessee proves could have been reasonably avoided; plus
d) any other amount necessary to compensate Lessor for all the detriment
proximately caused by Lessee's failure to perform his obligations under this
Lease or which in the ordinary course of things would be likely to result
therefrom; and e) at Lessor's election, such other amounts in addition to or in
lieu of the foregoing as may be permitted from time to time by applicable
California law.  As used in (a) and (b) above, the "worth at the time of award"
is computed by allowing interest at the rate of Wells Fargo's prime rate plus
two percent (2%) per annum.  As used in (c) above, the "worth at the time of
award" is computed by discounting such amount at the discount rate of the
Federal Reserve Bank of San Francisco at the time of award plus one percent
(1%).

PAGE 6


14.3 RIGHT OF ENTRY AND REMOVAL: In the event of any such default by Lessee,
Lessor shall also have the right, with or without terminating this Lease, to
re-enter the Premises and remove all persons and property from the Premises;
such property may be removed and stored in a public warehouse or elsewhere at
the cost of and for the account of Lessee.

14.4 ABANDONMENT: In the event of the vacation or abandonment, except as
provided in Section 7, of the Premises by Lessee or in the event that Lessor
shall elect to re-enter as provided in paragraph 14.3 above or shall take
possession of the Premises pursuant to legal proceeding or pursuant to any
notice provided by law, and Lessor does not elect to terminate this Lease as
provided in Section 14.2 above, then Lessor may from time to time, without
terminating this Lease, either recover all Rent as it becomes due or relet the
Premises or any part thereof for such term or terms and at such rental rates and
upon such other terms and conditions as Lessor, in its sole discretion, may deem
advisable with the right to make alterations and repairs to the Premises.  In
the event that Lessor elects to relet the Premises, then Rent received by Lessor
from such reletting shall be applied; first, to the payment of any indebtedness
other than Rent due hereunder from Lessee to Lessor; second, to the payment of
any cost of such reletting; third, to the payment of the cost of any alterations
and repairs to the Premises; fourth, to the payment of Rent due and unpaid
hereunder; and the residue, if any, shall be held by Lessor and applied to the
payment of future Rent as the same may become due and payable hereunder.  Should
that portion of such Rent received from such reletting during any month, which
is applied by the payment of Rent hereunder according to the application
procedure outlined above, be less than the Rent payable during that month by
Lessee hereunder, then Lessee shall pay such deficiency to Lessor immediately
upon demand therefor by Lessor.  Such deficiency shall be calculated and paid
monthly.  Lessee shall also pay to Lessor, as soon as ascertained, any costs and
expenses incurred by Lessor in such reletting or in making such alterations and
repairs not covered by the rentals received from such reletting.

14.5 NO IMPLIED TERMINATION: No re-entry or taking possession of the Premises by
Lessor pursuant to Section 14.3 or Section 14.4 of this Lease shall be construed
as an election to terminate this Lease unless a written notice of such intention
is given to Lessee or unless the termination thereof is decreed by a court of
competent jurisdiction.  Notwithstanding any reletting without termination by
Lessor because of any default by Lessee, Lessor may at any time after such
reletting elect to terminate this Lease for any such default. 

15. SURRENDER OF LEASE: The voluntary or other surrender of this Lease by
Lessee, or a mutual cancellation thereof, shall not work a merger, and shall, at
the option of Lessor, terminate all or any existing subleases or sub tenancies,
or may, at the option of Lessor, operate as an assignment to him of any or all
such subleases or sub tenancies.

16. TAXES: Lessee shall pay and discharge punctually and when the same shall
become due and payable without penalty, all real estate taxes, personal property
taxes, taxes based on vehicles utilizing parking areas in the Premises, taxes
computed or based on rental income (other than federal, state and municipal net
income taxes), environmental surcharges, privilege taxes, excise taxes, business
and occupation taxes, school fees or surcharges, gross receipts taxes, sales
and/or use taxes, employee taxes, occupational license taxes, water and sewer
taxes, assessments (including, but not limited to, assessments for public
improvements or benefit), assessments for local improvement and maintenance
districts, and all other governmental impositions and charges of every kind and
nature whatsoever, regardless of whether now customary or within the
contemplation of the parties hereto and regardless of whether resulting from
increased rate and/or valuation, or whether extraordinary or ordinary, general
or special, unforeseen or foreseen, or similar or dissimilar to any of the
foregoing (all of the foregoing being hereinafter collectively called "Tax" or
"Taxes") which, at any time during the Lease Term, shall be applicable or
against the Premises, or shall become due and payable and a lien or charge upon
the Premises under or by virtue of any present or future laws, statutes,
ordinances, regulations, or other requirements of any governmental authority
whatsoever.  The term "Environmental Surcharge" shall include any and all
expenses, taxes, charges or penalties imposed by the Federal Department of
Energy, Federal Environmental Protection Agency, the Federal Clean Air Act, or
any regulations promulgated thereunder, or any other local, state or federal
governmental agency or entity now or hereafter vested with the power to impose
taxes, assessments or other types of surcharges as a means of controlling or
abating environmental pollution or the use of energy in regard to the use,
operation or occupancy of the Premises.  The term "Tax" shall include, without
limitation, all taxes, assessments, levies, fees, impositions or charges levied,
imposed, assessed, measured, or based in any manner whatsoever (i) in whole or
in part on the Rent payable by Lessee under this Lease, (ii) upon or with
respect to the use, possession, occupancy, leasing, operation or management of
the Premises, (iii) upon this transaction or any document to which Lessee is a
party creating or transferring an 

PAGE 7


interest or an estate in the Premises, (iv) upon Lessee's business operations
conducted at the Premises, (v) upon, measured by or reasonably attributable to
the cost or value of Lessee's equipment, furniture, fixtures and other personal
property located on the Premises or the cost or value of any leasehold
improvements made in or to the Premises by or for Lessee, regardless of whether
title to such improvements shall be in Lessor or Lessee, or (vi) in lieu of or
equivalent to any Tax set forth in this Section 16.  In the event any such Taxes
are payable by Lessor and it shall not be lawful for Lessee to reimburse Lessor
for such Taxes, then the Rent payable thereunder shall be increased to net
Lessor the same net rent after imposition of any such Tax upon Lessor as would
have been payable to Lessor prior to the imposition of any such Tax.  It is the
intention of the parties that Lessor shall be free from all such Taxes and all
other governmental impositions and  charges of every kind and nature whatsoever.
However, nothing contained in this Section 16 shall require Lessee to pay any
Federal or State income, franchise, estate, inheritance, succession, transfer or
excess profits tax imposed upon Lessor.   If any general or special assessment
is levied and assessed against the Premises, Lessor agrees to use its best
reasonable efforts to cause the assessment to become a lien on the Premises
securing repayment of a bond sold to finance the improvements to which the
assessment relates which is payable in installments of principal and interest
over the maximum term allowed by law.  It is understood and agreed that Lessee's
obligation under this paragraph will be prorated to reflect the Commencement
Date and the end of the Lease Term.  It is further understood that if Taxes
cover the Premises and Lessee does not occupy the entire Premises, the Taxes
will be allocated to the portion of the Premises occupied by Lessee based on a
pro-rata square footage or other equitable basis, as determined by Lessor. 
Taxes billed by Lessor to Lessee shall be included in the monthly CAC.  

Subject to any limitations or restrictions imposed by any deeds of trust or
mortgages now or hereafter covering or affecting the Premises, Lessee shall have
the right to contest or review the amount or validity of any Tax by appropriate
legal proceedings but which is not to be deemed or construed in any way as
relieving, modifying or extending Lessee's covenant to pay such Tax at the time
and in the manner as provided in this Section 16.  However, as a condition of
Lessee's right to contest, if such contested Tax is not paid before such contest
and if the legal proceedings shall not operate to prevent or stay the collection
of the Tax so contested, Lessee shall, before instituting any such proceeding,
protect the Premises and the interest of Lessor and of the beneficiary of a deed
of trust or the mortgagee of a mortgage affecting the Premises against any lien
upon the Premises by a surety bond, issued by an insurance company acceptable to
Lessor and in an amount equal to one and one-half (1 1/2) times the amount
contested or, at Lessor's option, the amount of the contested Tax and the
interest and penalties in connection therewith.  Any contest as to the validity
or amount of any Tax, whether before or after payment, shall be made by Lessee
in Lessee's own name, or if required by law, in the name of Lessor or both
Lessor and Lessee.  Lessee shall defend, indemnify  and hold harmless Lessor
from and against any and all costs or expenses, including attorneys' fees, in
connection with any such proceedings brought by Lessee, whether in its own name
or not. Lessee shall be entitled to retain any refund of any such contested Tax
and penalties or interest thereon which have been paid by Lessee.  Nothing
contained herein shall be construed as affecting or limiting Lessor's right to
contest any Tax at Lessor's expense.

17. NOTICES: Unless otherwise provided for in this Lease, any and all written
notices or other communication (the "Communication") to be given in connection
with this Lease shall be given in writing and shall be given by personal
delivery, facsimile transmission or by mailing by registered or certified mail
with postage thereon or recognized overnight courier, fully prepaid, in a sealed
envelope addressed to the intended recipient as follows:

(a)  to the Lessor at:   10050 Bandley Drive
                         Cupertino, California 95014
                         Attention: Carl E. Berg
                         Fax No: (408) 725-1626

(b)  to the Lessee at:   10050 Bandley Drive
                         Cupertino, California
                         Attention: Michael J. Anderson
                         Fax No: (408) 725-1626

or such other addresses, facsimile number or individual as may be designated by
a Communication given by a party to the other parties as aforesaid.  Any
Communication given by personal delivery shall be conclusively deemed to have
been given and 

PAGE 8


received on a date it is so delivered at such address provided that such date is
a business day, otherwise on the first business day following its receipt, and
if given by registered or certified mail, on the day on which delivery is made
or refused or if given by recognized overnight courier, on the first business
day following deposit with such overnight courier and if given by facsimile
transmission, on the day on which it was transmitted provided such day is a
business day, failing which, on the next business day thereafter.   

18. ENTRY BY LESSOR: Lessee shall permit Lessor and its agents to enter into and
upon said Premises at all reasonable times using the minimum amount of
interference and inconvenience to Lessee and Lessee's business, subject to any
security regulations of Lessee, for the purpose of inspecting the same or for
the purpose of maintaining the building in which said Premises are situated, or
for the purpose of making repairs, alterations or additions to any other portion
of said building, including the erection and maintenance of such scaffolding,
canopies, fences and props as may be required, without any rebate of Rent and
without any liability to Lessee for any loss of occupation or quiet enjoyment of
the Premises; and shall permit Lessor and his agents, at any time within ninety
(90) days prior to the end of the Lease Term, to place upon said Premises any
usual or ordinary "For Sale" or "For Lease" signs and exhibit the Premises to
prospective tenants at reasonable hours.

19. DESTRUCTION OF PREMISES: In the event of a partial destruction of the said
Premises during the Lease Term from any cause which is covered by Lessor's
property insurance, Lessor shall forthwith repair the same, provided such
repairs can be made within ninety (90) days after receipt of building permit
under the laws and regulations of State, Federal, County, or Municipal
authorities, but such partial destruction shall in no way annul or void this
Lease, except that Lessee shall be entitled to a proportionate reduction of Rent
while such repairs are being made to the extent of payments received by Lessor
under its Loss of Rents Insurance coverage.  With respect to any partial
destruction which Lessor is obligated to repair or may elect to repair under the
terms of this paragraph, the provision of Section 1932, Subdivision 2, and of
Section 1933, Subdivision 4, of the Civil Code of the State of California are
waived by Lessee.  In the event that the building in which the subject Premises
may be situated is destroyed to an extent greater than thirty-three and
one-third percent (33 1/3%) of the replacement cost thereof, Lessor may, at its
sole option, elect to terminate this Lease, whether the subject Premises is
insured or not.  A total destruction of the building in which the subject
Premises are situated shall terminate this Lease.  Notwithstanding the above,
Lessor is only obligated to repair or rebuild to the extent of available
insurance proceeds including any deductible amount.  Should Lessor determine
that insufficient or no insurance proceeds are available for repair or
reconstruction of Premises, Lessor, at its sole option, may terminate the Lease.
Lessee shall have the option of continuing this Lease by agreeing to pay all
repair costs to the subject Premises.

20. ASSIGNMENT AND SUBLETTING: Lessee shall not assign this Lease, or any
interest therein, and shall not sublet the said Premises or any part thereof, or
any right or privilege appurtenant thereto, or cause any other person or entity
(a bona fide subsidiary or affiliate of Lessee excepted) to occupy or use the
Premises, or any portion thereof, without the advance written consent of Lessor.
Any such assignment or subletting without such consent shall be void, and shall,
at the option of the Lessor, terminate this Lease.  This Lease shall not, or
shall any interest therein, be assignable, as to the interest of Lessee, by
operation of law, without the written consent of Lessor.  Notwithstanding
Lessor's obligation to provide reasonable approval, Lessor reserves the right to
withhold its consent for any proposed sublessee or assignee of Lessee if the
proposed sublessee or assignee is a user or generator of Hazardous Materials. 
If Lessee desires to assign its rights under this Lease or to sublet, all or a
portion of the subject Premises to a party other than a bona fide subsidiary or
affiliate of Lessee, Lessee shall first notify Lessor of the proposed terms and
conditions of such assignment or subletting.  Lessor shall have the right of
first refusal to enter into a direct Lessor-lessee relationship with such party
under such proposed terms and conditions, in which event Lessee shall be
relieved of its obligations hereunder to the extent of the Lessor-lessee
relationship entered into between Lessor and such third party.  Notwithstanding
the foregoing, Lessee may assign this Lease to a successor in interest, whether
by merger or acquisition, provided there is no substantial reduction in the net
worth of the resulting entity and the resulting entity is not a user or
generator of Hazardous Materials.  Whether or not Lessor's consent to a sublease
or assignment is required, in the event of any sublease or assignment, Lessee
shall be and shall remain primarily liable for the performance of all
conditions, covenants, and obligations of Lessee hereunder and, in the event of
a default by an assignee or sublessee, Lessor may proceed directly against the
original Lessee hereunder and/or any other predecessor of such assignee or
sublessee without the necessity of exhausting remedies against said assignee or
sublessee.

PAGE 9


21. CONDEMNATION: If any part of the Premises shall be taken for any public or
quasi-public use, under any statute or by right of eminent domain or private
purchase in lieu thereof, and a part thereof remains which is susceptible of
occupation hereunder, this Lease shall as to the part so taken, terminate as of
the date title vests in the condemnor or purchaser, and the Rent payable
hereunder shall be adjusted so that the Lessee shall be required to pay for the
remainder of the Lease Term only that portion of Rent as the value of the part
remaining.  The rental adjustment resulting will be computed at the same Rental
rate for the remaining part not taken; however, Lessor shall have the option to
terminate this Lease as of the date when title to the part so taken vests in the
condemnor or purchaser.  If all of the Premises, or such part thereof be taken
so that there does not remain a portion susceptible for occupation hereunder,
this Lease shall thereupon terminate.  If a part or all of the Premises be
taken, all compensation awarded upon such taking shall be payable to the Lessor.
Lessee may file a separate claim and be entitled to any award granted to Lessee.

22. EFFECTS OF CONVEYANCE: The term "Lessor" as used in this Lease, means only
the owner for the time being of the land and building constituting the Premises,
so that, in the event of any sale of said land or building, or in the event of a
Lease of said building, Lessor shall be and hereby is entirely freed and
relieved of all covenants and obligations of Lessor hereunder, and it shall be
deemed and construed, without further agreement between the parties and the
purchaser of any such sale, or the Lessor of the building, that the purchaser or
lessor of the building has assumed and agreed to carry out any and all covenants
and obligations of the Lessor hereunder.  If any security is given by Lessee to
secure the faithful performance of all or any of the covenants of this Lease on
the part of Lessee, Lessor may transfer and deliver the security, as such, to
the purchaser at any such sale of the building, and thereupon the Lessor shall
be discharged from any further liability.

23. SUBORDINATION: This Lease, in the event Lessor notifies Lessee in writing,
shall be subordinate to any ground lease, deed of trust, or other hypothecation
for security now or hereafter placed upon the real property at which the
Premises are a part and to any and all advances made on the security thereof and
to renewals, modifications, replacements and extensions thereof. Lessee agrees
to promptly execute any documents which may be required to effectuate such
subordination. Notwithstanding such subordination, if Lessee is not in default
and so long as Lessee shall pay the Rent and observe and perform all of the
provisions and covenants required under this Lease, Lessee's right to quiet
possession of the Premises shall not be disturbed or effected by any
subordination.

24. WAIVER: The waiver by Lessor of any breach of any term, covenant or
condition, herein contained shall not be construed to be a waiver of such term,
covenant or condition or any subsequent breach of the same or any other term,
covenant or condition therein contained.  The subsequent acceptance of Rent
hereunder by Lessor shall not be deemed to be a waiver of Lessee's breach of any
term, covenant, or condition of the Lease.

25. HOLDING OVER: Any holding over after the end of the Lease Term requires
Lessor's written approval prior to the end of the Lease Term, which,
notwithstanding any other provisions of this Lease, Lessor may withhold.  Such
holding over shall be construed to be a tenancy at sufferance from month to
month.  Lessee shall pay to Lessor monthly base rent equal to one and one-half
(1.5) times the monthly base rent installment due in the last month of the Lease
Term and all other additional rent and all other terms and conditions of the
Lease shall apply, so far as applicable.  Holding over by Lessee without written
approval of Lessor shall subject Lessee to the liabilities and obligations
provided for in this Lease and by law, including, but not limited to those in
Section 2 of this Lease.  Lessee shall indemnify and hold Lessor harmless
against any loss or liability resulting from any delay caused by Lessee in
surrendering the Premises, including without limitation, any claims made or
penalties incurred by any succeeding lessee or by Lessor.  No holding over shall
be deemed or construed to exercise any option to extend or renew this Lease in
lieu of full and timely exercise of any such option as required hereunder.

26. LESSOR'S LIABILITY: If Lessee should recover a money judgment against Lessor
arising in connection with this Lease, the judgment shall be satisfied only out
of the Lessor's interest in the Premises and neither Lessor or any of its
partners shall be liable personally for any deficiency.

27. ESTOPPEL CERTIFICATES: Lessee shall at any time during the Lease Term, upon
not less than ten (10) days prior written notice from Lessor, execute and
deliver to Lessor a statement in writing certifying that, this Lease is
unmodified and in full force and effect (or, if modified, stating the nature of
such modification) and the dates to which the Rent and other charges have been
paid 

PAGE 10


in advance, if any, and acknowledging that there are not, to Lessee's knowledge,
any uncured defaults on the part of Lessor hereunder or specifying such defaults
if they are claimed.  Any such statement may be conclusively relied upon by any
prospective purchaser or encumbrancer of the Premises.  Lessee's failure to
deliver such a statement within such time shall be conclusive upon the Lessee
that (a) this Lease is in full force and effect, without modification except as
may be represented by Lessor; (b) there are no uncured defaults in Lessor's
performance.

28. TIME: Time is of the essence of the Lease.

29. CAPTIONS: The headings on titles to the paragraphs of this Lease are not a
part of this Lease and shall have no effect upon the construction or
interpretation of any part thereof.  This instrument contains all of the
agreements and conditions made between the parties hereto and may not be
modified orally or in any other manner than by an agreement in writing signed by
all of the parties hereto or their respective successors in interest.

30. PARTY NAMES: Landlord and Tenant may be used in various places in this Lease
as a substitute for Lessor and Lessee respectively.

31. EARTHQUAKE INSURANCE: As a condition of Lessor agreeing to waive the
requirement for earthquake insurance, Lessee agrees that it will pay, as
additional Rent, which shall be included in the monthly CAC, an amount not to
exceed One Thousand Two Hundred Eighty Dollars ($1,280) per year for earthquake
insurance if Lessor desires to obtain some form of earthquake insurance in the
future, if and when available, on terms acceptable to Lessor as determined in
the sole and absolute discretion of Lessor.

32. HABITUAL DEFAULT: Notwithstanding anything to the contrary contained in
Section 14 herein, Lessor and Lessee agree that if Lessee shall have defaulted
in the payment of Rent for three or more times during any twelve month period
during the Lease Term, then such conduct shall, at the option of the Lessor,
represent a separate event of default which cannot be cured by Lessee.  Lessee
acknowledges that the purpose of this provision is to prevent repetitive
defaults by the Lessee under the Lease, which constitute a hardship to the
Lessor and deprive the Lessor of the timely performance by the Lessee hereunder.

33. HAZARDOUS MATERIALS
33.1 DEFINITIONS: As used in this Lease, the following terms shall have the
following meaning:
     a. The term "Hazardous Materials" shall mean (i) polychlorinated biphenyls;
     (ii) radioactive materials and (iii) any chemical, material or substance
     now or hereafter defined as or included in the definitions of "hazardous
     substance" "hazardous water", "hazardous material", "extremely hazardous
     waste", "restricted hazardous waste" under Section 25115, 25117 or 15122.7,
     or listed pursuant to Section 25140 of the California Health and Safety
     Code, Division 20, Chapter 6.5 (Hazardous Waste Control Law), (ii) defined
     as "hazardous substance" under Section 25316 of the California Health and
     Safety Code, Division 20, Chapter 6.8 (Carpenter-Presley-Tanner Hazardous
     Substances Account Act), (iii) defined as "hazardous material", "hazardous
     substance", or "hazardous waste" under Section 25501 of the California
     Health and Safety Code, Division 20, Chapter 6.95 (Hazardous Materials
     Release, Response, Plans and Inventory), (iv) defined as a "hazardous
     substance" under Section 25181 of the California Health and Safety Code,
     Division 20l, Chapter 6.7 (Underground Storage of Hazardous Substances),
     (v) petroleum, (vi) asbestos, (vii) listed under Article 9 or defined as
     "hazardous" or "extremely hazardous" pursuant to Article II of Title 22 of
     the California Administrative Code, Division 4, Chapter 20, (viii) defined
     as "hazardous substance" pursuant to Section 311 of the Federal Water
     Pollution Control Act, 33 U.S.C. 1251 et seq. or listed pursuant to Section
     1004 of the Federal Water Pollution Control Act (33 U.S.C. 1317), (ix)
     defined as a "hazardous waste", pursuant to Section 1004 of the Federal
     Resource Conservation and Recovery Act, 42 U.S.C. 6901 et seq., (x) defined
     as "hazardous substance" pursuant to Section 101 of the Comprehensive
     Environmental Responsibility Compensations, and Liability Act, 42 U.S.C.
     9601 et seq., or (xi) regulated under the Toxic Substances Control Act, 156
     U.S.C. 2601 et seq.
     b. The term "Hazardous Materials Laws" shall mean any local, state and
     federal laws, rules, regulations, or ordinances relating to the use,
     generation, transportation, analysis, manufacture, installation, release,
     discharge, storage or disposal of Hazardous Material.

PAGE 11


     c. The term "Lessor's Agents" shall mean Lessor's agents, representatives,
     employees, contractors, subcontractors, directors, officers and partners.
     d. The term "Lessee's Agents" shall mean Lessee's agents, representatives,
     employees, contractors, subcontractors, directors, officers, partners,
     invitees or any other person in or about the Premises.

33.2 LESSEE'S RIGHT TO INVESTIGATE: Lessee shall be entitled to cause such
inspection, soils and ground water tests, and other evaluations to be made of
the Premises as Lessee deems necessary regarding (i) the presence and use of
Hazardous Materials in or about the Premises, and (ii) the potential for
exposure to Lessee's employees and other persons to any Hazardous Materials used
and stored by previous occupants in or about the Premises.  Lessee shall provide
Lessor with copies of all inspections, tests and evaluations.  Lessee shall
indemnify, defend and hold Lessor harmless from any cost, claim or expense
arising from such entry by Lessee or from the performance of any such
investigation by such Lessee.

33.3 LESSOR'S REPRESENTATIONS: Lessor hereby represents and warrants to the best
of Lessor's knowledge that the Premises are, as of the date of this Lease, in
compliance with all Hazardous Material Laws.

33.4 LESSEE'S OBLIGATION TO INDEMNIFY: Lessee, at its sole cost and expense,
shall indemnify, defend, protect and hold Lessor and Lessor's Agents harmless
from and against any and all cost or expenses, including those described under
subparagraphs i, ii and iii herein below set forth, arising from or caused in
whole or in part, directly or indirectly by:
     a. Lessee's or Lessee's Agents' use, analysis, storage, transportation,
     disposal, release, threatened release, discharge or generation of Hazardous
     Material to, in, on, under, about or from the Premises; or
     b. Lessee's or Lessee's Agents failure to comply with Hazardous Material
     laws; or
     c. Any release of Hazardous Material to, in, on, under, about, from or onto
     the Premises caused by or occurring as a result of acts or omissions of
     Lessee or Lessee's Agents or occurring during the Lease Term, except ground
     water contamination from other parcels where the source is from off the
     Premises not arising from or caused by Lessee or Lessee's Agents.
The cost and expenses indemnified against include, but are not limited to the
following:
     i. Any and all claims, actions, suits, proceedings, losses, damages,
     liabilities, deficiencies, forfeitures, penalties, fines, punitive damages,
     cost or expenses;
     ii. Any claim, action, suit or proceeding for personal injury (including
     sickness, disease, or death), tangible or intangible property damage,
     compensation for lost wages, business income, profits or other economic
     loss, damage to the natural resources of the environment, nuisance,
     pollution, contamination, leaks, spills, release or other adverse effects
     on the environment;
     iii. The cost of any repair, clean-up, treatment or detoxification of the
     Premises necessary to bring the Premises into compliance with all Hazardous
     Material Laws, including the preparation and implementation of any closure,
     disposal, remedial action, or other actions with regard to the Premises,
     and expenses (including, without limitation, reasonable attorney's fees and
     consultants fees, investigation and laboratory fees, court cost and
     litigation expenses).

33.5 LESSEE'S OBLIGATION TO REMEDIATE CONTAMINATION: Lessee shall, at its sole
cost and expense, promptly take any and all action necessary to remediate
contamination of the Premises by Hazardous Materials during the Lease Term.

33.6 OBLIGATION TO NOTIFY: Lessor and Lessee shall each give written notice to
the other as soon as reasonably practical of (i) any communication received from
any governmental authority concerning Hazardous Material which related to the
Premises and (ii) any contamination of the Premises by Hazardous Materials which
constitutes a violation of any Hazardous Material Laws.
 
33.7 SURVIVAL: The obligations of Lessee under this Section 33 shall survive the
Lease Term or earlier termination of this Lease.  

33.8 CERTIFICATION AND CLOSURE: On or before the end of the Lease Term or
earlier termination of this Lease, Lessee shall deliver to Lessor a
certification executed by Lessee stating that, to the best of Lessee's
knowledge, there exists no violation of Hazardous Material Laws resulting from
Lessee's obligation in Paragraph 33.  If pursuant to local ordinance, state or
federal law, Lessee is required, at the expiration of the Lease Term, to submit
a closure plan for the Premises to a local, state or federal agency, then Lessee
shall furnish to Lessor a copy of such plan.

PAGE 12


33.9 PRIOR HAZARDOUS MATERIALS: Lessee shall have no obligation to clean up or
to hold Lessor harmless with respect to, any Hazardous Material or wastes
discovered on the Premises which were not introduced into, in, on, about, from
or under the Premises during the Lease Term or ground water contamination from
other parcels where the source is from off the Premises not arising from or
caused by Lessee or Lessee's Agents.

34. BROKERS: Lessor and Lessee represent that they have not utilized or
contacted a real estate broker or finder with respect to this Lease. and Lessee
agrees to indemnify and hold Lessor harmless against any claim, cost, liability
or cause of action asserted by any broker or finder claiming through Lessee 
Lessor represents and warrants that it has not utilized or contacted a real
estate broker or finder with respect to this Lease and Lessor agrees to
indemnify and hold Lessee harmless against any claim, cost, liability or cause
of action asserted by any broker or finder claiming through Lessor.

35. OPTION TO EXTEND
A. OPTION: Lessor hereby grants to Lessee one (1) option to extend the Lease
Term, with the extended term to be for a period of three (3) years, on the
following terms and conditions:

     (i) Lessee shall give Lessor written notice of its exercise of its option
     to extend no earlier than twenty-four (24) calendar months, nor later than
     six (6) calendar months before the Lease Term would end but for said
     exercise.  Time is of the essence.

     (ii) Lessee may not extend the Lease Term pursuant to any option granted by
     this Section 35 if Lessee is in default as of the date of the exercise of
     its option.  If Lessee has committed a default by Lessee as defined in
     Section 14 or 32 that has not been cured or waived by Lessor in writing by
     the date that any extended term is to commence, then Lessor may elect not
     to allow the Lease Term to be extended, notwithstanding any notice given by
     Lessee of an exercise of this option to extend.

     (iii) All terms and conditions of this Lease shall apply during the
     extended term, except that the base rent and rental increases for each
     extended term shall be determined as provided in Section 35 (B) below

     (iv) Lessee must provide Lessor written notice of its exercise of its
     option as provided hereunder at least nine (9) months before the Lease Term
     would end but for said exercise for purposes of negotiating rental terms. 
     Lessee may withdraw its notice of exercise of an extension option for any
     reason prior to six (6) months before the Lease Term would end but for said
     exercise.  Lessor shall provide Lessee with Lessor's proposed base monthly
     rent for the option period within twenty (20) days of Lessee's written
     request.  However, once Lessee delivers a notice of exercise of an option
     to extend the Lease Term it may not be withdrawn unless notice in writing
     is provided to Lessor at least six (6) months before the Lease Term would
     end but for said exercise and, subject to the provisions of this Section
     35, such notice shall operate to extend the Lease Term.  Upon any extension
     of the Lease Term pursuant to this Section 35, the term "Lease Term" as
     used in this Lease shall thereafter include the then extended term. 

     (v) The option rights of Mission West Properties  granted under this
     Section 35 are granted for Mission West Properties' personal benefit and
     may not be assigned or transferred by Mission West Properties or exercised
     if Mission West Properties is not occupying the Premises at the time of
     exercise.

B. EXTENDED TERM RENT - OPTION PERIOD: The monthly Rent for the Premises during
the extended term shall equal the fair market monthly Rent for the Premises as
of the commencement date of the extended term, but in no case, less than the
Rent during the last month of the prior Lease term.  Promptly upon Lessee's
exercise of the option to extend, Lessee and Lessor shall meet and attempt to
agree on the fair market monthly Rent for the Premises as of the commencement
date of the extended term.  In the event the parties fail to agree upon the
amount of the monthly Rent for the extended term prior to commencement thereof,
the monthly Rent for the extended term shall be determined by appraisal in the
manner hereafter set forth; provided, however, that in no event shall the
monthly Rent for the extended term be less than in the immediate preceding
period.  Annual base rent increases during the extended term shall be four
percent (4%) per year.  In the event it becomes necessary under this paragraph 

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to determine the fair market monthly Rent of the Premises by appraisal, Lessor
and Lessee each shall appoint a real estate appraiser who shall be a member of
the American Institute of Real Estate Appraiser ("AIREA") and such appraisers
shall each determine the fair market monthly Rent for the Premises taking into
account the value of the Premises and the amenities provided by the outside
areas, the common areas, and the Building, and prevailing comparable Rentals in
the area.  Such appraisers shall, within twenty (20) business days after their
appointment, complete their appraisals and submit their appraisal reports to
Lessor and Lessee.  If the fair market monthly Rent of the Premises established
in the two (2) appraisals varies by five percent (5%) or less of the higher
Rent, the average of the two shall be controlling.  If said fair market monthly
Rent varies by more than five percent (5%) of the higher Rental, said
appraisers, within ten (10) days after submission of the last appraisal, shall
appoint a third appraiser who shall be a member of the AIREA and who shall also
be experienced in the appraisal of Rent values and adjustment practices for
commercial properties in the vicinity of the Premises.  Such third appraiser
shall, within twenty (20) business days after his appointment, determine by
appraisal the fair market monthly Rent of the Premises taking into account the
same factors referred to above, and submit his appraisal report to Lessor and
Lessee.  The fair market monthly Rent determined by the third appraiser for the
Premises shall be controlling, unless it is less than that set forth in the
lower appraisal previously obtained, in which case the value set forth in said
lower appraisal shall be controlling, or unless it is greater than that set
forth in the higher appraisal previously obtained in which case the Rent set for
in said higher appraisal shall be controlling.  If either Lessor or Lessee fails
to appoint an  appraiser, or if an appraiser appointed by either of them fails,
after his appointment to submit his appraisal within the required period in
accordance with the foregoing, the appraisal submitted by the appraiser properly
appointed and timely submitting his appraisal shall be controlling.  If the two
appraisers appointed by Lessor and Lessee are unable to agree upon a third
appraiser within the required period in accordance with the foregoing,
application shall be made within twenty (20) days thereafter by either Lessor or
Lessee to AIREA, which shall appoint a member of said institute willing to serve
as appraiser.  The cost of all appraisals under this subparagraph shall be borne
equally be Lessor and Lessee.

36. APPROVALS: Whenever in this Lease the Lessor's or Lessee's consent is
required, such consent shall not be unreasonably or arbitrarily withheld or
delayed.  In the event that the Lessor or Lessee does not respond to a request
for any consents which may be required of it in this Lease within ten business
days of the request of such consent in writing by the Lessee or Lessor, such
consent shall be deemed to have been given by the Lessor or Lessee.

37. AUTHORITY: Each party executing this Lease represents and warrants that he
or she is duly authorized to execute and deliver the Lease.  If executed on
behalf of a corporation, that the Lease is executed in accordance with the
by-laws of said corporation (or a partnership that the Lease is executed in
accordance with the partnership agreement of such partnership), that no other
party's approval or consent to such execution and delivery is required, and that
the Lease is binding upon said individual, corporation (or partnership) as the
case may be in accordance with its terms.  

38. INDEMNIFICATION OF LESSOR: Except to the extent caused by the sole
negligence or willful misconduct of Lessor or Lessor's Agents, Lessee shall
defend, indemnify and hold Lessor harmless from and against any and all
obligations, losses, costs, expenses, claims, demands, attorney's fees,
investigation costs or liabilities on account of, or arising out of the use,
condition or occupancy of the Premises or any act or omission to act of Lessee
or Lessee's Agents or any occurrence in, upon, about or at the Premises,
including, without limitation, any of the foregoing provisions arising out of
the use, generation, manufacture, installation, release, discharge, storage, or
disposal of Hazardous Materials by Lessee or Lessee's Agents.  It is understood
that Lessee is and shall be in control and possession of the Premises and that
Lessor shall in no event be responsible or liable for any injury or damage or
injury to any person whatsoever, happening on, in, about, or in connection with
the Premises, or for any injury or damage to the Premises or any part thereof. 
This Lease is entered into on the express condition that Lessor shall not be
liable for, or suffer loss by reason of injury to person or property, from
whatever cause, which in any way may be connected with the use, condition or
occupancy of the Premises or personal property located herein. The provisions of
this Lease permitting Lessor to enter and inspect the Premises are for the
purpose of enabling Lessor to become informed as to whether Lessee is complying
with the terms of this Lease and Lessor shall be under no duty to enter, inspect
or to perform any of Lessee's covenants set forth in this Lease.  Lessee shall
further indemnify, defend and hold harmless Lessor from and against any and all
claims arising from any breach or default in the performance of any obligation
to Lessee's part to be performed under the terms of this Lease.  The provisions
of Section 38 shall survive the Lease Term or earlier termination of this Lease
with respect to any damage, injury or death occurring during the Lease Term.  

PAGE 14


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

40. MISCELLANEOUS PROVISIONS: All rights and remedies hereunder are cumulative
and not alternative to the extent permitted by law and are in addition to all
other rights or remedies in law and in equity.

41. CHOICE OF LAW:  This lease shall be construed and enforced in accordance
with the substantive laws of the State of California.  The language of all parts
of this lease shall in all cases be construed as a whole according to its fair
meaning and not strictly for or against either Lessor or Lessee.

42. ENTIRE AGREEMENT:  This Lease is the entire agreement between the parties,
and there are no agreements or representations between the parties except as
expressed herein.  Except as otherwise provided for herein, no subsequent change
or addition to this Lease shall be binding unless in writing and signed by the
parties hereto.

IN WITNESS WHEREOF, Lessor and Lessee have executed this Lease, the day and year
first above written.


LESSOR                                   LESSEE
BERG & BERG ENTERPRISES, INC.            MISSION WEST PROPERTIES

By:                                      By:
   ---------------------------              ---------------------------
signature of authorized                  Signature of authorized
representative                           representative

Carl E. Berg                             Michael J. Anderson
- ------------------------------           ------------------------------
printed name                             printed name


- ------------------------------           ------------------------------
title                                    Title


- ------------------------------           ------------------------------
date                                     Date

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