Exhibit 10.63  10600
  North De Anza Blvd.
  408.446.0700Suite
  200
  Facsimile:
  408.446.0583Cupertino,
  CA 95014-2075
  www.sobrato.com    SOBRATODEVELOPMENT COMPANIES  Lease
between Sobrato
Interests and Affymetrix  SectionPARTIESPREMISESUSETERM AND RENTALLATE
  CHARGESPOSSESSIONACCEPTANCE OF POSSESSION AND
  COVENANTS TO SURRENDERUSES PROHIBITEDALTERATIONS AND ADDITIONSMAINTENANCE OF PREMISESLandlord and Tenants Obligations
  Regarding Common Area CostsCommon Area CostsTenants Allocable ShareWaiver of LiabilityTenants ObligationsHAZARD INSURANCETenants
  UseLandlords InsuranceTenants InsuranceWaiverTAXESUTILITIESABANDONMENTFREE FROM LIENSCOMPLIANCE WITH
  GOVERNMENTAL REGULATIONSTOXIC WASTE AND
  ENVIRONMENTAL DAMAGETenants Responsibility  i 
   Tenants Indemnity Regarding Hazardous MaterialsLandlords Indemnity Regarding Hazardous MaterialsINDEMNITYADVERTISEMENTS AND SIGNSATTORNEYS FEESTENANTS DEFAULTRemediesRight to Re-enterAbandonmentNo TerminationSURRENDER OF LEASEHABITUAL DEFAULTLANDLORDS DEFAULTNOTICESENTRY BY LANDLORDDESTRUCTION OF PREMISESDestruction by an Insured CasualtyDestruction by an Uninsured CasualtyDestruction by an Uninsured CasualtyASSIGNMENT OR SUBLEASEConsent by LandlordAssignment or Subletting ConsiderationNo ReleaseEffect of DefaultCONDEMNATIONEFFECTS OF CONVEYANCESUBORDINATIONWAIVERHOLDING OVERSUCCESSORS AND ASSIGNSESTOPPEL CERTIFICATESOPTION TO EXTEND THE LEASE TERMGrant and Exercise of OptionDetermination of Fair Market RentalResolution of a Disagreement over the Fair
  Market RentalOPTIONS  ii 
   QUIET ENJOYMENTBROKERSThis section intentionally left blankAUTHORITY OF PARTIESMISCELLANEOUS PROVISIONSRentManagement FeePerformance by LandlordInterestRights and RemediesSurvival of IndemnitiesSeverabilityChoice
  of LawTimeEntire AgreementRepresentationsHeadingsEXHIBIT
  A\  iii 
   10600
  North De Anza Blvd.
  408.446.0700Suite
  200
  Facsimile:
  408.446.0583Cupertino,
  CA 95014-2075
  www.sobrato.com  SOBRATODEVELOPMENT COMPANIES  1.        PARTIES:    THIS LEASE, is entered into on this 3RD day
of July, 2002, between Sobrato Interests, a California limited partnership, and
Affymetrix, Inc., a California corporation, hereinafter called respectively
Landlord and Tenant.  2.        PREMISES:    Landlord hereby leases to Tenant, and
Tenant hires from Landlord those certain premises (Premises) with the
appurtenances, situated in the City of Santa Clara, County of Santa Clara,
State of California, and more particularly described as follows, to-wit:  That certain real property commonly known and designated as 3420
Central Expressway consisting of 108,720 rentable square feet (Building) and
370 parking stalls in a project consisting of a total of five (5) buildings,
including the Premises, totaling 412,171 square feet (Project) as outlined in
red on Exhibit A. The parking stalls shall be available for Tenants
exclusive use but shall not be designated or segregated from the balance of the
parking area.  3.        USE:    Tenant shall use the Premises only for the
following purposes and shall not change the use of the Premises without the
prior written consent of Landlord: 
Office, research, development, testing, light manufacturing, ancillary
warehouse, and related legal uses. 
Landlord makes no representation or warranty that any specific use of
the Premises desired by Tenant is permitted pursuant to any Laws.  4.        TERM AND RENTAL:    The term (Lease Term) shall be for one
hundred eight (108) months, commencing on the 1st day of September 1, 2004
(Commencement Date), and ending on the 31st day of August, 2013, (Expiration
Date).  In addition to all other sums
payable by Tenant under this Lease, Tenant shall pay base monthly rent (Base
Monthly Rent) for the Premises according to the following schedule:  September 1, 2004 through August 31, 2006:
  
  $152,208.00 per monthSeptember 1, 2006 through August 31, 2008:
  
  $168,516.00 per monthSeptember 1, 2008 through August 31, 2013:
  
  $183,737.00 per month  1 
   Base Monthly Rent shall be due on or before the first day of each
calendar month during Lease Term. All sums payable by Tenant under this Lease
shall be paid in lawful money of the United States of America, without offset
or deduction, and shall be paid to Landlord at such place or places as may be
designated from time to time by Landlord. Base Monthly Rent for any period less
than a calendar month shall be a pro rata portion of the monthly installment.
Concurrently with Tenants execution of this Lease, Tenant shall pay to
Landlord the sum of One Hundred Fifty Seven Thousand Six Hundred Forty Four
Dollars ($157,644.00) as prepaid rent for the first month of the Lease Term.  Tenant shall be allowed a 4-month period of early access to the
Premises immediately prior to the Commencement Date (Early Access Period) for
the purpose of installing Initial Improvements (as defined in Section 7 below)
and otherwise preparing for its occupancy. Tenant shall be subject to all the
terms and conditions of the Lease during the Early Access Period except that no
Base Monthly Rent or other expenses or amounts shall be due or payable
(excluding utility charges incurred by Tenant).  5.        LATE CHARGES:   
Tenant hereby acknowledges that late payment by Tenant to Landlord of
Base Monthly Rent and other sums due hereunder will cause Landlord to incur
costs not contemplated by this Lease, the exact amount of which will be
extremely difficult to ascertain. Such costs include, but are not limited to,
administrative, processing, accounting charges, and late charges, which may be
imposed on Landlord by the terms of any contract, revolving credit, mortgage or
trust deed covering the Premises. Accordingly, if any installment of Base
Monthly Rent or any other sum due from Tenant shall not be received by Landlord
or Landlords designee within ten (10) days after Tenants receipt of written
notice from Landlord that such amount is due, Tenant shall pay to Landlord a
late charge equal to five (5%) percent of such overdue amount which shall be
due and payable with the payment then delinquent. Landlord agrees to waive said
late charge in the event the Base Monthly Rent or other sum due is received
within five (5) days after receipt by Tenant of Landlords written notice. The
parties hereby agree that such late charge represents a fair and reasonable
estimate of the costs Landlord will incur by reason of late payment by Tenant.
Acceptance of such late charge by Landlord shall in no event constitute a
waiver of Tenants default with respect to such overdue amount, nor prevent
Landlord from exercising any of the other rights and remedies granted
hereunder. In the event that a late charge is payable hereunder, whether or not
collected, for three (3) consecutive installments of Base Monthly Rent, then
rent shall automatically become due and payable quarterly in advance, rather
than monthly, notwithstanding any provision of this Lease to the contrary.  2 
   IT IS FURTHER
MUTUALLY AGREED BETWEEN THE PARTIES AS FOLLOWS:  6.        POSSESSION:    If
Landlord, for any reason whatsoever, cannot deliver possession of the said
Premises to Tenant at the Commencement Date, as hereinbefore specified, this
Lease shall not be void or voidable, nor shall Landlord 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, and Tenant
shall in all cases retain its right to the Early Access Period as defined in
Section 4 above, so that the commencement Date shall in no event occur until
the expiration of the Early Access Period. 
The above is however, subject to the provision that the period of delay
of delivery of the Premises shall not exceed 120 days from the scheduled
Commencement Date. If the period of delay of delivery exceeds the foregoing,
Tenant, at its option, may cancel this Lease on written notice to Landlord
within seven (7) business days thereafter and declare it null and void.  Notwithstanding the foregoing, Landlord
agrees avail itself of all legal remedies to evict the current occupant of the
Premises if it does not vacate by the expiration date of its lease.  7.        ACCEPTANCE
OF POSSESSION AND COVENANTS TO SURRENDER:    On
the date Landlord tenders possession for the commencement of the Early Access
Period, Landlord shall deliver the keys to the Premises to Tenant and Tenant
shall accept possession from Landlord. Landlord shall reimburse Tenant for the
costs incurred by Tenant to put the HVAC system in good condition and repair,
as detailed in an inspection report to be issued by Therma Mechanical within
150 days prior to the Commencement Date. During the first year of the Lease
Term, Tenant intends to make certain modifications (Initial Improvements) to
the Premises.  Tenant shall comply with
the provisions of Lease paragraph 9 in its construction of the Initial Improvements.  The Tenant agrees on the Expiration Date, or
on the sooner termination of this Lease, to surrender the Premises to Landlord
in good condition and repair, reasonable wear and tear excepted.  Good condition shall mean that the
interior walls, floors, suspended ceilings, and carpeting within the Premises
will be cleaned to the same condition as existed at completion of the Initial
Improvements, normal wear and tear excepted. Tenant agrees, at its sole cost,
to remove all phone and data cabling installed by Tenant from the suspended
ceiling and repair or replace broken ceiling tiles, and relevel the ceiling if
required, but otherwise Tenant shall have no obligation to remove the Initial
Improvements. Tenant shall ascertain from Landlord within thirty (30) days
before the Expiration Date whether Landlord desires to have the Premises or any
part or parts thereof restored to their condition as of the completion of the
Initial Improvements or to cause Tenant to surrender all Alterations in place
to  3 
   Landlord. If Landlord shall so desire, then Tenant shall remove such
Alterations as Landlord may require and shall repair and restore said Premises
or such part or parts thereof before the Expiration Date at Tenants sole cost
and expense. Tenant on or before the Expiration Date or sooner termination of
this Lease, shall remove all its personal property and trade fixtures from the
Premises, and all property and fixtures not so removed shall be deemed to be
abandoned by Tenant. If the Premises are not surrendered at the Expiration Date
or sooner termination of this Lease in the condition required by this
paragraph, Tenant shall indemnify, defend, and hold harmless Landlord against
loss or liability resulting from delay by Tenant in so surrendering the
Premises including, without limitation, any claims made by any succeeding
tenant founded on such delay.  Notwithstanding the provisions of this paragraph 7, Landlord shall at
its sole expense repair all latent defects respecting the Premises. Landlords
obligations with respect to the correction of such defects shall be limited to
the cost to correct the defective work and Landlord shall not be liable for any
consequential damages or other loss or damage incurred by Tenant.  8.        USES PROHIBITED:Tenant shall not commit, or suffer to be committed, any waste upon the
said Premises, or any nuisance, or other act or thing which may disturb the
quiet enjoyment of any other tenant in or around the Building or allow any sale
by auction upon the Premises, or allow the Premises to be used for any unlawful
or objectionable purpose, or place any loads upon the floor, walls, or ceiling
which endanger the structure, or use any machinery or apparatus which will in
any manner vibrate or shake the Building, or place any harmful liquids, waste
materials, or hazardous materials in the drainage system of, or upon or in the
soils surrounding the Building.  No
materials, supplies, equipment, finished products or semi-finished products,
raw materials or articles of any nature or any waste materials, refuse, scrap
or debris shall be stored upon or permitted to remain on any portion of the
Premises outside of the Building proper without Landlords prior approval,
which approval may be withheld in its sole discretion.  9.        ALTERATIONS
AND ADDITIONS:    Tenant shall not make, or suffer to be
made, any alteration or addition to the said Premises (Alterations), or any
part thereof, without (i) the written consent of Landlord first had and
obtained, which consent shall not be unreasonably withheld or delayed, and (ii)
delivering to Landlord the proposed architectural and structural plans for all
such Alterations.  Any Alterations,
except movable furniture and trade fixtures, shall become at once a part of the
realty and belong to Landlord. Alterations which are not to be deemed as trade
fixtures shall include heating, lighting, electrical systems, air conditioning,
partitioning, carpeting, or any other installation which has become an integral
part of the Premises.   After having
obtained  4 
   Landlords consent, Tenant agrees that it will not proceed to make such
Alterations until (i) Tenant has obtained all required governmental approvals
and permits, and (ii) Tenant has provided Landlord reasonable security, in form
reasonably requested by Landlord, to protect Landlord against mechanics lien
claims. Tenant further agrees to provide Landlord (i) written notice of the
anticipated start date and actual start date of the work, and (ii) a complete
set of half-size (15 X 21) vellum as-built drawings. All Alterations shall be
constructed in compliance with applicable buildings codes and laws, including
Title 24 and ADA, and shall be maintained, replaced or repaired at Tenants
sole cost and expense.  Notwithstanding the foregoing, Tenant shall be entitled without
obtaining Landlords consent to make any Alteration to the Premises which does
not affect the structure of the Building, provided that each such Alteration
costs no more than $50,000, and all such Alterations in any twelve (12) month
period do not exceed an aggregate of $100,000.  10.     MAINTENANCE
OF PREMISES:  A.       Landlord and Tenants Obligations Regarding Common
Area Costs: Landlord shall, at its sole cost and expense, maintain in good
condition, order, and repair, and replace as and when necessary, the
foundation, exterior load bearing walls and roof structure of the Building
shell. Landlord agrees to perform the maintenance, repair and replacement of
those items defined in paragraph 10(B) below for which Common Area Costs are
incurred.  Tenant agrees to reimburse
Landlord for the expenses resulting from Landlords payment of Common Area
Costs as defined in paragraph 10(B) incurred by Landlord because the cost is
not directly allocable to or payable by a single tenant in the Building or the
Project. Tenant agrees to pay Tenants Allocable Share as defined in paragraph
10(C) of the Common Area Costs, as additional rental, within thirty (30) days
of written invoice from Landlord.  B.       Common Area Costs:   
For purposes of calculating Tenants Allocable Share of Building and of
Project Costs, the term Common Area Costs shall mean all costs and expenses
of the nature hereinafter described which are incurred in connection with
ownership, maintenance and operation of the Building or the Project in which
the Premises are located, as the case may be not directly allocable to or
payable by a single tenant in the Building or the Project, together with such additional
facilities as may be determined by Landlord to be reasonably desirable or
necessary to the ownership and operation of the Building and/or Project. All
costs and expenses shall be determined in accordance with generally accepted
accounting principles which shall be consistently applied  5 
   (with accruals appropriate to Landlords business), including but not
limited to, the following: (i) common area utilities, including water and power
and lighting to the extent not separately metered; (ii) common area maintenance
and service agreements for the Building or the Project and the equipment
therein including, without limitation, common area janitorial services, alarm
and security services, exterior window cleaning, and maintenance of sidewalks,
landscaping, waterscape, parking areas, and driveways; (iii) insurance premiums
and costs, including without limitation, the premiums and cost of fire,
casualty and liability coverage and rental abatement and earthquake (if
commercially available) insurance applicable to the Building or Project; (iv)
repairs, replacements and general maintenance (excluding repairs and general
maintenance paid by proceeds of insurance or by Tenant or other third parties,
and repairs or alterations attributable solely to tenants of the Building or
Project other than Tenant); and (v) all real estate taxes, special assessments,
service payments in lieu of taxes, excises, transit charges, housing fund
assessment, levies, fees or charges and including any substitutes or additions
thereto which may occur during the Lease Term (and Renewal Terms, if any) of
this Lease which are assessed, or imposed by any public authority upon the
Building or Project, the act of entering this Lease, the occupancy by Tenant,
the rent provided for in this Lease and including real estate tax increases due
to a sale or transfer of the Building or the Project, in which the Premises are
located, as such taxes are levied or appear on the City and County tax bills
and assessment rolls. All special assessments shall be paid over the longest
period allowed by the taxing authority. This shall be a net lease and the Base
Monthly Rent shall be paid to Landlord absolutely net of all costs and
expenses, except as otherwise specifically provided in this Lease. The
provision for payment of Common Area Costs by means of periodic payment of
Tenants Allocable Share of Building and/or Project Costs are intended to pass
on to Tenant and reimburse Landlord for all costs of operating and managing the
Building and/or Project.  C.      Tenants
Allocable Share:    For purposes of prorating Common Area
Costs which Tenant shall pay, Tenants Allocable Share of Building Costs is
computed by multiplying the total Common Area Costs for services shared by the
Building by a fraction, the numerator of which is the rentable square footage
of the Premises and the denominator of which is the total rentable square
footage of the Building (excluding common areas). Tenants Allocable Share of
Project Costs shall be computed on a shared service by service basis, by
multiplying the total Common Area Costs for services shared by the Building and
one or more buildings in the Project by a fraction, the numerator of which is
the rentable square footage of the Premises and the denominator of which is the
total rentable square footage of the Buildings in the Project which share the
services. It is understood and agreed by Landlord and Tenant that Tenants
Allocable Share of Building Costs is 100.00% and of Project Costs is 26.4%. It
is understood and agreed that Tenants obligation to share in Common  6 
   Area Costs shall be adjusted to reflect the commencement and
termination dates of the Lease Term and are subject to recalculation in the
event of expansion of the Building or Project.  D.       Waiver of
Liability:    Failure by Landlord to perform any defined
services, or any cessation thereof, when such failure is caused by accident,
breakage, repairs, strikes, lockout or other labor disturbances or labor
disputes of any character, or by any other cause, similar or dissimilar, beyond
the reasonable control of Landlord, shall not render Landlord liable in any
respect for damages to either person or property, nor be construed as an
eviction of Tenant, nor cause an abatement of rent nor relieve Tenant from
fulfillment of any covenant or agreement hereof. Should any of the equipment or
machinery utilized in supplying the services listed herein break down, or for
any cause cease to function properly, upon receipt of written notice from
Tenant of any deficiency or failure of any defined services, Landlord shall use
reasonable diligence to repair the same promptly, but Tenant shall have no
right to terminate this Lease, and shall have no claim for rebate of rent or
damages, on account of any interruptions in service occasioned thereby or
resulting therefrom. Tenant waives the provisions of California Civil Code
Sections 1941 and 1942 concerning the Landlords obligation of tenantability and
Tenants right to make repairs and deduct the cost of such repairs from the
rent.  Landlord shall not be liable for
a loss of or injury to property, however occurring, through or in connection
with or incidental to furnishing or its failure to furnish any of the
foregoing, unless such loss or injury is due to the negligence or willful
misconduct of Landlord, or Landlords breach of its obligations under this
Lease.  E.       Tenants
Obligations:    Except as provided in section 10(A) above,
Tenant shall, at its sole cost, keep and maintain, repair and replace, said
Premises and appurtenances and every part hereof, including but not limited to,
exterior walls, roof membrane, glazing, plumbing, electrical and HVAC systems,
and all the Initial Improvements and Alterations in good and sanitary order,
condition, and repair; normal wear and tear and damage by casualty excepted.
Tenant shall provide Landlord with a copy of a service contract between Tenant
and a licensed air-conditioning and heating contractor which contract shall
provide for bi-monthly maintenance of all air conditioning and heating
equipment at the Premises. Tenant shall pay the cost of all air-conditioning
and heating equipment repairs or replacements which are either excluded from
such service contract or any existing equipment warranties. All wall surfaces
and floor tile are to be maintained in an as good a condition as when Tenant
took possession free of holes, gouges, or defacements. Tenant agrees to limit
attachments to vinyl demountable wall surfaces exclusively to V-joints.  Tenant shall also be responsible for the preventive maintenance of the
membrane of the roof, which  7 
   responsibility shall be deemed properly discharged if (i) Tenant contracts
with a licensed roof contractor who is reasonably satisfactory to both Tenant
and Landlord, at Tenants sole cost, to inspect the roof membrane at least
every six (6) months, with the first inspection due the sixth (6th) month after
the Commencement Date, and (ii) Tenant performs, at Tenants sole cost, all
preventive maintenance recommendations made by such contractor within a
reasonable time after such recommendations are made. Such preventive
maintenance might include acts such as clearing storm gutters and drains,
removing debris from the roof membrane, trimming trees overhanging the roof
membrane, applying coating materials to seal roof penetrations, repairing
blisters, and other routine measures. Tenant shall provide to Landlord a copy
of such preventive maintenance contract and paid invoices for the recommended
work.  Notwithstanding the provisions of this Section 10, in the event a
replacement under Sec 10.B. or 10.E: (i) would be properly be capitalized under
generally accepted accounting principles; and (ii) costs in excess of $7,500,
Tenant shall only be required to pay that portion of the cost equal to the
product of such total cost multiplied by a fraction, the numerator of which is
the number of years remaining in the Lease Term, the denominator of which is
the useful life (in years) of the replacement.  11.     HAZARD INSURANCE:  A.       Tenants Use:   
Tenant shall not use, or permit said Premises, or any part thereof, to
be used, for any purpose other than that for which the said Premises are hereby
leased; and no use shall be made or permitted to be made of the said Premises,
nor acts done, which will cause an increase in premiums or a cancellation of
any insurance policy covering said Building, or any part thereof, nor shall
Tenant sell or permit to be kept, used or sold, in or about said Premises, any
article which may be prohibited by the standard form of fire insurance
policies. 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 said Building and appurtenances.  B.       Landlords
Insurance:    Landlord agrees to purchase and keep in
force fire and extended coverage, earthquake (at Landlords election and at a
commercially reasonable rate), and 12 month rental loss insurance covering the
Premises in amounts not to exceed the actual insurable value of the Building as
determined by Landlords insurance companys appraisers. Tenant agrees to pay
to Landlord as additional rent, on demand, the full cost of said insurance as
evidenced by insurance billings to Landlord, and in the event of damage covered
by said insurance, the amount of  8 
   any deductible under such policy. Payment shall be due to Landlord
within thirty (30) days after written invoice to Tenant. Tenant consents to
Landlords current insurance deductible of $5,000.00 and shall have the right
to approve any future change in the deductible amount in its sole and
reasonable discretion. It is understood and agreed that Tenants obligation
under this paragraph will be prorated to reflect the commencement and
termination dates of this Lease.  C.       Tenants
Insurance:    Tenant, at its sole cost, agrees to insure
its personal property, Initial Improvements and Alterations for amounts not to
exceed their actual insurable value and to obtain workers compensation and
public liability and property damage insurance for occurrences within the
Premises with a $5,000,000.00 combined single limit for bodily injury and
property damage. Tenant shall name Landlord and Landlords lender as an
additional insured, shall deliver a copy of the policies and renewal
certificates to Landlord.  All such
policies shall provide for thirty (30) days prior written notice to Landlord
of any cancellation, termination, or reduction in coverage. Notwithstanding the
above, Landlord retains the right to have Tenant provide other forms of
insurance which may be reasonably required to cover future risks, provided such
insurance is generally obtained by prudent property owners of comparable
buildings in the Santa Clara area.  D.       Waiver:   
Landlord and Tenant hereby waive any and all rights each may have
against the other on account of any loss or damage occasioned to the Landlord
or the Tenant as the case may be, or to the Premises or its contents, and which
may arise from any risk covered by their respective insurance policies, as set
forth above.  The parties shall use
their reasonable efforts to obtain from their respective insurance companies a
waiver of any right of subrogation which said insurance company may have
against the Landlord or the Tenant, as the case may be.  12.     TAXES:   
Tenant shall be liable and shall pay prior to delinquency all taxes and
assessments levied against personal property and trade or business fixtures,
and agrees to pay, as additional rental, all real estate taxes and assessment
installments (special or general) or other impositions or charges which may be
levied on the Premises, upon the occupancy of the Premises and including any
substitute or additional charges which may be imposed during, or applicable to
the Lease Term including real estate tax increases due to a sale or other
transfer of the Premises, as they appear on the City and County tax bills
during the Lease Term, and as they become due. It is understood and agreed that
Tenants obligation under this paragraph will be prorated to reflect the
commencement and termination dates of this Lease. In any time during the Lease
Term a tax, excise on rents, business license tax, or any other tax, however
described, is levied or assessed against Landlord, as a substitute in whole or
in part for taxes assessed or imposed on land or Buildings,  9 
   Tenant
shall pay and discharge its pro rata share of such tax or excise on rents or
other tax before it becomes delinquent, except that this provision is not
intended to cover net income taxes, inheritance, gift or estate tax imposed
upon Landlord. In the event that a tax is placed, levied, or assessed against
Landlord and the taxing authority takes the position that the Tenant cannot pay
and discharge its pro rata share of such tax on behalf of Landlord, then at the
sole election of Landlord, Landlord may increase the rental charged hereunder
by the exact amount of such tax and Tenant shall pay such increase as
additional rent hereunder.  13.     UTILITIES:   
Tenant shall pay directly to the providing utility all water, gas, heat,
light, power, telephone and other utilities supplied to the Premises. Landlord
shall not be liable for a loss of or injury to property, however occurring,
through or in connection with or incidental to furnishing or failure to furnish
any of utilities to the Premises and Tenant shall not be entitled to abatement
or reduction of any portion of the Base Monthly Rent so long as any failure to
provide and furnish the utilities to the Premises due to any cause beyond Landlords
reasonable control.  14.     ABANDONMENT:   
Tenant shall not abandon the Premises at any time during the Lease Term;
and if Tenant shall abandon or surrender said Premises, or be dispossessed by
process of law, or otherwise, any personal property belonging to Tenant and
left on the Premises shall be deemed to be abandoned, at the option of
Landlord, except such property as may be mortgaged to Landlord. Notwithstanding
the foregoing, Tenant shall be entitled to suspend its operations on the
Premises and vacate the Premises provided that Tenant continues to timely pay
rent and perform all other obligations of Tenant under this Lease, and further
provided that Tenant provides a security guard or other reasonable security
protection for the Premises.  15.     FREE FROM LIENS:   
Tenant shall keep the Premises and the Building free from any liens
arising out of any work performed, materials furnished, or obligations incurred
by Tenant or claimed to have been performed for Tenant.  In the event Tenant fails to discharge any
such lien within ten (10) days after receiving notice of the filing, Landlord
shall be entitled to discharge such lien at Tenants expense and all resulting
costs incurred by Landlord, including attorneys fees shall be due from Tenant
as additional rent.  Notwithstanding the provisions of this paragraph 15, Tenant shall have
the right to contest such liens if Tenant obtains a bond equal to 150% of the
amount of such lien to prevent enforcement of the lien during such contest or
otherwise makes adequate provision to prevent enforcement of the lien during
such contest.  10 
   16.     COMPLIANCE
WITH GOVERNMENTALREGULATIONS:    Tenant shall, at its sole
cost and expense, comply with all of the requirements of all Municipal, State
and Federal authorities now in force, or which may hereafter be in force,
pertaining to the said Premises, and shall faithfully observe in the use of the
Premises all Municipal ordinances and State and Federal statutes now in force
or which may hereafter be in force. The judgment of any court of competent
jurisdiction, or the admission of Tenant in any action or proceeding against
Tenant, whether Landlord be a party thereto or not, that Tenant has violated
any such ordinance or statute in the use of the Premises, shall be conclusive
of that fact as between Landlord and Tenant.  Notwithstanding the provisions of this paragraph 16 and excepting Title
24 and ADA work for which Tenant is responsible due to Tenants Initial
Improvements or Alterations, if any improvement or alteration to the Premises
is required as a result of any laws or regulations affecting the Premises not
related to Tenants specific use of the Premises, and provided further said
improvement or alteration is not required because of Alterations to the
Premises made by Tenant, Tenant shall notify Landlord and Landlord shall
perform such improvement or alteration and the cost thereof shall be allocated
between Landlord and Tenant such that Tenant shall pay to Landlord upon
completion of such improvement, the portion of the cost thereof equal to the
remaining number of years in the Lease Term divided by the anticipated useful
life of such improvement. Landlord represents and warrants, to the best of its
knowledge, that the Building shell complies with all building codes that were
applicable as of the date of its construction.  17.     TOXIC
WASTE AND ENVIRONMENTAL DAMAGE:  A. Tenants
Responsibility:    Without the prior written consent of
Landlord, Tenant shall not bring, use, or permit upon the Premises, or
generate, emit, or dispose from the Premises any chemicals, toxic or hazardous
gaseous, liquid or solid materials or waste, including without limitation,
material or substance having characteristics of ignitability, corrosivity,
reactivity, or toxicity or substances or materials which are listed on any of
the Environmental Protection Agencys lists of hazardous wastes or which are
identified in Sections 66680 through 66685 of Title 22 of the California
Administrative Code as the same may be amended from time to time (Hazardous
Materials). In order to obtain consent, Tenant shall deliver to Landlord its
written proposal describing the toxic material to be brought onto the Premises,
measures to be taken for storage and disposal thereof, safety measures to be
employed to prevent pollution of the air, ground, surface and ground water.
Landlord consents to Tenants use of Hazardous Materials on the Premises on the  11 
   condition
that Tenant represents and warrants that Tenant will (i) adhere to all
reporting and inspection requirements imposed by Federal, State, County or
Municipal laws, ordinances or regulations and will provide Landlord a copy of
any such reports or agency inspections, (ii) obtain and provide Landlord copies
of all necessary permits required for the use and handling Hazardous Materials
on the Premises, (iii) enforce Hazardous Materials handling and disposal
practices consistent with industry standards, and (iv) properly close the
facility with regard to Hazardous Materials including the removal or
decontamination of any process piping, mechanical ducting, storage tanks,
containers, or trenches which have come into contact with Hazardous Materials
and obtain a closure certificate from the local administering agency prior to
the Expiration Date. Landlord may employ an independent engineer or consultant
to periodically inspect Tenants operations to verify that Tenant is complying
with its obligations under this paragraph. In the event it is determined by
Landlords consultant that Tenant is in material violation with respect to its
obligations under this paragraph and such violation has not previously been
reported by Tenant or has not been cured, then Tenant shall pay the reasonable
future expense of employing Landlords independent engineer or consultant to
periodically inspect Tenants operations. The forgoing right of inspection
shall be exercised by Landlord only if Landlord believes it may be subject to
liability because of Tenants handling of hazardous materials.  B.       Tenants
Indemnity RegardingHazardous Materials:   
Tenant shall comply, at its sole cost, with all laws pertaining to, and
shall indemnify and hold Landlord harmless from any claims, liabilities, costs
or expenses incurred or suffered by Landlord, except through Landlords
negligence or willful misconduct, arising from such bringing, using,
permitting, generating, emitting or disposing of Hazardous Materials.  Tenants indemnification and hold harmless
obligations include, without limitation, (i) claims, liability, costs or
expenses resulting from or based upon administrative, judicial (civil or
criminal) or other action, legal or equitable, brought by any private or public
person under common law or under the Comprehensive Environmental Response,
Compensation and Liability Act of 1980 (CERCLA), the Resource Conservation
and Recovery Act of 1980 (RCRA) or any other Federal, State, County or
Municipal law, ordinance or regulation, (ii) claims, liabilities, costs or
expenses pertaining to the identification, monitoring, cleanup, containment, or
removal of Hazardous Materials from soils, riverbeds or aquifers including the
provision of an alternative public drinking water source, and (iii) all costs of
defending such claims.  C.       Landlords
Indemnity Regarding Hazardous Materials:   
Landlord shall indemnify and hold Tenant harmless from any claims,
liabilities, costs or expenses incurred or suffered by Tenant related to the
removal, investigation, monitoring or remediation of Hazardous Materials  12 
   which are present or which come to be present on the Premises through
no fault of Tenant. Landlords indemnification and hold harmless obligations
include, without limitation, (i) claims, liability, costs or expenses resulting
from or based upon administrative, judicial (civil or criminal) or other
action, legal or equitable, brought by any private or public person under
common law or under the Comprehensive Environmental Response, Compensation and
Liability Act of 1980 (CERCLA), the Resource Conservation and Recovery Act of
1980 (RCRA) or any other Federal, State, County or Municipal law, ordinance
or regulation, (ii) claims, liabilities, costs or expenses pertaining to the
identification, monitoring, cleanup, containment, or removal of Hazardous
Materials from soils, riverbeds or aquifers including the provision of an
alternative public drinking water source, and (iii) all costs of defending such
claims. In no event shall Landlord be liable for any consequential damages
suffered or incurred by Tenant as a result of any such contamination.  18.     INDEMNITY:    As
a material part of the consideration to be rendered to Landlord, Tenant hereby
waives all claims against Landlord for damages to goods, wares and merchandise,
and all other personal property in, upon or about said Building, for injuries
to persons in or about said Building, or for injuries or claims by Tenants
agents or invitees in or about the Project, from any cause arising at any time
except due to the negligence or willful misconduct of Landlord, or Landlords
breach of its obligations under this Lease, and Tenant will hold Landlord
exempt and harmless from any damage or injury to any person, or to the goods,
wares and merchandise and all other personal property of any person, arising
from the use of the Premises by Tenant, or from the failure of Tenant to keep
the Building in good condition and repair, as herein provided. Further, in the
event Landlord is made party to any litigation due to the acts or omissions of
Tenant covered by this indemnity, Tenant will indemnify and hold Landlord
harmless from any such claim or liability including Landlords costs and
expenses and reasonable attorneys fees incurred in defending such claims.  19.     ADVERTISEMENTS
AND SIGNS:    Tenant will not place or permit to be
placed, in, upon or about the said Premises any unusual or extraordinary signs,
or any signs not approved by the city or other governing authority.  The Tenant will not place, or permit to be
placed, upon the Premises, any signs, advertisements or notices without the
written consent of Landlord as to type, size, design, lettering, coloring and
location, and such consent will not be unreasonably withheld. Any sign so
placed on the Premises shall be removed by Tenant, at its expense, prior to the
Expiration Date or promptly following the earlier termination of the lease and
Tenant shall repair any damage or injury to the Premises caused thereby, and if
not so removed by Tenant then Landlord may have same so removed at Tenants
expense.  13 
   20.     ATTORNEYS FEES:    In
case suit should be brought for the possession of the Premises, for the
recovery of any sum due hereunder, or because of the breach of any other
covenant herein, the losing party shall pay to the prevailing party a
reasonable attorneys fee as part of its costs which shall be deemed to have
accrued on the commencement of such action.  21.     TENANTS DEFAULT:   
The occurrence of any of the following shall constitute a material
default and breach of this Lease by Tenant: a) Any failure by Tenant to pay the
rental or to make any other payment required to be made by Tenant hereunder
provided however, that Tenant may cure such default by payment to Landlord of
the Base Monthly Rent or other sum due within ten (10) days after receipt by
Tenant of written notice specifying Landlord has failed to receive the amount
in question; b) The abandonment of the Premises by Tenant; c) A failure by
Tenant to observe and perform any other provision of this Lease to be observed
or performed by Tenant, where such failure continues for thirty (30) days after
written notice thereof by Landlord to Tenant; provided, however, that if the
nature of such default is such that the same cannot reasonably be cured within
such thirty (30) day period Tenant shall not be deemed to be in default if
Tenant shall within such period commence such cure and thereafter diligently
prosecute the same to completion; d) The making by Tenant of any general
assignment for the benefit of creditors; the filing by or against Tenant of a
petition to have Tenant adjudged a bankrupt or of a petition for reorganization
or arrangement under any law relating to bankruptcy (unless, in the case of a
petition filed against Tenant, the same is dismissed after the filing); the
appointment of a trustee or receiver to take possession of substantially all of
Tenants assets located at the Premises or of Tenants interest in this Lease,
where possession is not restored to Tenant within thirty (30) days; or the
attachment, execution or other judicial seizure of substantially all of
Tenants assets located at the Premises or of Tenants interest in this Lease,
where such seizure is not discharged within thirty (30) days.  The notice requirements set forth herein are
in lieu of and not in addition to the notices required by California Code of
Civil Procedure Section 1161.  A.      Remedies:    In the event of any such
default by Tenant, then in addition to any other remedies available to Landlord
at law or in equity, Landlord shall have the immediate option to terminate this
Lease and all rights of Tenant hereunder by giving written notice of such
intention to terminate. In the event that Landlord shall elect to so terminate
this Lease then Landlord may recover from Tenant: a) the worth at the time of
award of any unpaid rent which had been earned at the time of such termination;
plus b) the worth at the time of award of the amount by which the unpaid rent
would have been earned after termination until the time of award exceeds the
amount of such rental  14 
   loss
Tenant proves could have been reasonably avoided; plus c) the worth at the time
of award of the amount by which the unpaid rent for the balance of the Lease
Term after the time of award exceeds the amount of such rental loss that Tenant
proves could be reasonably avoided; plus d) any other amount necessary to
compensate Landlord for all the detriment directly and foreseeably caused by
Tenant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
Landlords election, such other amounts in addition to or in lieu of the
foregoing as may be permitted from time to time by applicable California law.
The term rent, as used herein, shall be deemed to be and to mean the minimum
monthly installments of Base Monthly Rent and all other sums required to be
paid by Tenant pursuant to the terms of this Lease, all other such sums being
deemed to be additional rent due hereunder. As used in (a) and (b) above, the
worth at the time of award to be computed by allowing interest at the rate of
the discount rate of the Federal Reserve Bank of San Francisco plus five (5%)
percent per annum. As used in (c) above, the worth at the time of award to be
computed by discounting such amount at the discount rate of the Federal Reserve
Bank of San Francisco at the time of award plus one (1%) percent.  B.       Right to Re-enter:    In
the event of any such default by Tenant, Landlord shall also have the right,
with or without terminating this Lease, to re-enter the Premises and remove all
persons and property from the Premises (subject to compliance with California
law); such property may be removed and stored in a public warehouse or
elsewhere at the cost of and for the account of Tenant and disposed of by
Landlord in any manner permitted by law.  C.       Abandonment:    In
the event of the abandonment of the Premises by Tenant or in the event that
Landlord shall elect to re-enter as provided in paragraph 21(B) above or shall
take possession of the Premises pursuant to legal proceeding or pursuant to any
notice provided by law, then if Landlord does not elect to terminate this Lease
as provided in paragraph 21(A) above, then the provisions of California Civil
Code Section 1951.4, as amended from time to time, shall apply and Landlord may
from time to time, without terminating this Lease, either recover all rental as
it becomes due or relet the Premises or any part thereof for such term or terms
and at such rental or rentals and upon such other terms and conditions as
Landlord in its sole discretion may deem advisable with the right to make
alterations and repairs to the Premises. In the event that Landlord shall elect
to so relet, then rentals received by Landlord from such reletting shall be
applied: first, to the payment of any indebtedness other than Base Monthly Rent
due hereunder from Tenant to Landlord; second, to the payment of any cost of
such reletting; third, to the payment of the cost of any reasonable alterations
and repairs to the Premises; fourth, to the payment of Base Monthly Rent due
and unpaid hereunder; and the residue, if any, shall be held by Landlord and
applied in  15 
   payment of future Base Monthly Rent as the same may become due and
payable hereunder. Should that portion of such rentals received from such
reletting during any month, which is applied by the payment of rent hereunder,
be less than the rent payable during that month by Tenant hereunder, then
Tenant shall pay such deficiency to Landlord immediately upon demand therefor
by Landlord. Such deficiency shall be calculated and paid monthly. Tenant shall
also pay to Landlord, as soon as ascertained, any costs and expenses incurred
by Landlord in such reletting or in making such alterations and repairs not
covered by the rentals received from such reletting.  D.      No Termination:    No
re-entry or taking possession of the Premises by Landlord pursuant to 21(B) or
21(C) of this Article 22 shall be construed as an election to terminate this
Lease unless a written notice of such intention be given to Tenant or unless
the termination thereof be decreed by a court of competent jurisdiction.
Notwithstanding any reletting without termination by Landlord because of any
default by Tenant, Landlord may at any time after such reletting elect to
terminate this Lease for any such default.  22.     SURRENDER OF LEASE:   
The voluntary or other surrender of this Lease by Tenant, or a mutual
cancellation thereof, shall not automatically effect a merger of the Lease with
Landlords ownership of the Building or Premises. Instead, at the option of
Landlord, Tenants surrender may terminate all or any existing sublease or
subtenancies, or may operate as an assignment to Landlord of any or all such
subleases or subtenancies, thereby creating a direct Landlord-Tenant
relationship between Landlord and any subtenants.  23.     HABITUAL DEFAULT:   
Notwithstanding anything to the contrary contained in paragraph 21, 21
(A) (B) (C) and (D), the parties hereto agree that if the Tenant shall have
defaulted in the performance of any (but not necessarily the same) term or
condition of this Lease for three or more times during any twelve month period
during the Lease Term hereof, and such default has not been cured within any
applicable cure period, then such conduct shall, at the election of the
Landlord, represent a separate event of default which cannot be cured by the
Tenant.  Tenant acknowledges that the
purpose of this provision is to prevent repetitive defaults by the Tenant under
the Lease, which work a hardship upon the Landlord, and deprive the Landlord of
the timely performance by the Tenant hereunder.  24.     LANDLORDS DEFAULT:   
In the event of Landlords failure to perform any of its covenants or
agreements under this Lease, Tenant shall give Landlord written notice of such
failure and shall give Landlord thirty (30) days or such other reasonable
opportunity to cure or to  16 
   commence
to cure such failure prior to any claim for breach or for damages resulting
from such failure; provided that in the event of an emergency, Landlord shall
use best efforts to respond on an expedited basis. Without limiting any other
remedies available under this Lease or at law, if Tenant is prevented from
operating its business in the Premises for a period of three (3) business days
due to Landlords default under this Lease, then for each additional day that
Tenant is unable to operate, Base Monthly Rent shall be abated. In addition,
upon any such failure by Landlord, Tenant shall give notice by registered or
certified mail to any person or entity with a security interest in the Premises
(Mortgagee) that has provided Tenant with notice of its interest in the
Premises, and shall provide such Mortgagee a reasonable opportunity to cure
such failure, including such time as is necessary to obtain possession of the
Premises by power of sale or judicial foreclosure, if such should prove
necessary to effectuate a cure. Tenant agrees that each of the Mortgagees to
whom this Lease has been assigned is an expressed third party beneficiary
hereof. Tenant shall not make any prepayment of rent more than one (1) month in
advance without the prior written consent of such Mortgagee. Tenant waives any
right under California Civil Code Section 1950.7 or any other present or future
law to the collection of any payment or deposit from such Mortgagee or any
purchaser at a foreclosure sale of such Mortgagees interest unless such
Mortgagee or such purchaser shall have actually received and not refunded the
applicable payment or deposit.  25.      NOTICES:   
All notices, demands, requests, or consents required to be given under
this Lease shall be sent in writing by U.S. certified mail, return receipt
requested, or by personal delivery addressed to the party to be notified at the
address for such party specified in paragraph 1 of this Lease, or to such other
place as the party to be notified may from time to time designate by at least
fifteen (15) days prior notice to the notifying party.  26.      ENTRY BY LANDLORD:   
Tenant shall permit Landlord and his agents to enter into and upon said
Premises at all reasonable times, upon reasonable notice, and subject to any
security regulations of Tenant for the purpose of inspecting the same or for
the purpose of maintaining the Premises or for the purpose of making repairs,
alterations or additions to any other portion of said Premises or for the
purpose of erecting additional building(s) and improvements on the land where
the Premises are situated, or on adjacent land owned by Landlord, including the
erection and maintenance of such scaffolding, canopies, fences and props as may
be required without any abatement or reduction of Base Monthly Rent or without
any liability to Tenant for any loss of occupation or quiet enjoyment of the
Premises thereby occasioned, except as provided in the last sentence of this
paragraph; and Tenant shall permit Landlord and his agents, at any time within
one hundred eighty (180) days prior to the Expiration Date (or at any time
during the Lease if Tenant is  17 
   in default hereunder), to place upon the Premises any For Sale or
For Lease signs and exhibit the Premises to real estate brokers and
prospective tenants at reasonable hours. Landlord shall comply with Tenants
security procedures applicable to the Premises and shall not unreasonably
interfere with Tenants use or access of the Premises.  27.     DESTRUCTION
OF PREMISES:  A.       Destruction by an Insured Casualty:    In
the event of a partial destruction of the Premises by a casualty for which
Landlord has received insurance proceeds sufficient to repair the damage or
destruction during the Lease Term from any cause, Landlord shall forthwith
repair the same, provided such repairs can be made within one hundred eighty
(180) days from the date of receipt of all necessary governmental approvals
necessary under the laws and regulations of State, Federal, County or Municipal
authorities, such partial destruction shall in no way annul or void this Lease,
except that Tenant shall be entitled to a proportionate reduction of Base
Monthly Rent while such repairs are being made, such proportionate reduction to
be based upon the extent to which the making of such repairs shall interfere
with the business carried on by Tenant in the Premises. For purposes of this
paragraph partial destruction shall mean destruction of no greater than
one-third (1/3) of the replacement cost of the Premises, including the
replacement cost of the Tenant Improvements paid for by Landlord. In the event
the Premises are more than partially destroyed, or in the event the repairs
cannot be made in one hundred eighty (180) days, Landlord or Tenant may elect
to terminate this Lease.  Landlord shall
not be required to restore Initial Improvements, Alterations or replace Tenants
fixtures or personal property.  In
respect to any partial destruction which Landlord is obligated to repair or may
elect to repair under the terms of this paragraph, the provision of Section
1932, Subdivision 2, and of Section 1933, Subdivision 4, of the Civil Code of
the State of California and any other similarly enacted statue are waived by
Tenant and the provisions of this paragraph 28 shall govern in the case of
such destruction.  B.       Destruction by an Uninsured Casualty:    In
the event of a total or partial destruction of the Premises by an uninsured
casualty, the Lease shall automatically terminate, unless Landlord elects to
rebuild. In the event of a destruction by an uninsured casualty (i) of greater
than one-third (1/3) of the replacement cost of the Premises, or (ii) that can
not be repaired within one hundred eighty (180) days from the date of receipt
of all necessary governmental approvals necessary under the laws and
regulations of State, Federal, County or Municipal authorities, Tenant may elect
to terminate this Lease.  18 
   C.      Destruction
at End of Term:    In the event of a casualty damaging more
than one-third (1/3) of the Premises during the last year of the Term, either
Tenant or Landlord shall have the right to terminate this Lease upon written
notice to the other party.  28.     ASSIGNMENT OR
SUBLEASE:  A. Consent
by Landlord:    In the event Tenant desires to assign this
Lease or any interest therein including, without limitation, a pledge, mortgage
or other hypothecation, or sublet the Premises or any part thereof, Tenant
shall deliver to Landlord substantially complete forms of any such agreement
and of all ancillary agreements with the proposed assignee or subtenant,
financial statements, and any additional information as reasonably required to
determine whether it will consent to the proposed assignment or sublease. The
notice shall give the name and current address of the proposed
assignee/subtenant, proposed use of the Premises, rental rate and current
financial statement; and upon request to Tenant, Landlord shall be given
additional information as reasonably required to determine whether it will
consent to the proposed assignment or sublease. Landlord shall then have a
period of ten (10) days following receipt of such notice within which to notify
Tenant in writing that Landlord elects: (i) to permit Tenant to assign or
sublet such space to the named assignee/subtenant on the terms and conditions
set forth in the notice, or (ii) to refuse consent. If Landlord should fail to
notify Tenant in writing of such election within said ten (10) day period,
Landlord shall be deemed to have elected option (i) above. Landlords consent
(which must be in writing and in form reasonably satisfactory to Landlord) to
the proposed assignment or sublease shall not be unreasonably withheld or
delayed, provided and upon condition that: (i) The proposed assignee or
subtenant is engaged in a business that is limited to the use expressly
permitted under this Lease; (ii) The proposed sublease shall be in form
reasonably satisfactory to Landlord; (iii) Tenant shall reimburse Landlord on
demand for any reasonable costs that may be incurred by Landlord in connection
with said assignment or sublease, including the costs of making investigations
as to the acceptability of the proposed assignee or subtenant and legal costs
incurred in connection with the granting of any requested consent; and (iv)
Tenant shall not have advertised or publicized in any way the availability of
the Premises without prior notice to Landlord.  Notwithstanding
the provisions of this paragraph 28, Tenant may, without Landlords prior
written consent and without Landlords participation in subleasing profits,
sublet the Premises or assign the Lease to: (i) a subsidiary, affiliate,
division or corporation controlled or under common control with Tenant; (ii) a
successor corporation related to Tenant by merger, consolidation,
non-bankruptcy reorganization, or government action; or (iii) a purchaser of substantially
all of Tenants assets. For  19 
   the purpose of this Lease, sale of Tenants capital stock through any
public exchange shall not be deemed an assignment, subletting, or any other
transfer of the Lease or the Premises.  B.       Assignment
or SublettingConsideration:    Any rent or other economic
consideration realized by Tenant under any such sublease and assignment in
excess of the rent payable hereunder (including an allocation of the purchase
price attributable to Tenants leasehold interest in the event of a sale of the
Tenants business), after the net unamortized cost of the Tenant Improvements
for which Tenant has itself paid, and reasonable subletting and assignment
costs, shall be divided and paid fifty percent (50%) to Landlord and fifty
percent (50%) to Tenant. Tenants obligation to pay over Landlords portion of
the consideration shall constitute an obligation for additional rent hereunder.
The above provisions relating to Landlords right to terminate the Lease and
relating to the allocation of bonus rent are independently negotiated terms of
the Lease, constitute a material inducement for the Landlord to enter into the
Lease, and are agreed as between the parties to be commercially reasonable.  No assignment or subletting by Tenant shall
relieve Tenant of any obligation under this Lease.  Any assignment or subletting which conflicts with the provisions
hereof shall be void.  C.       No Release:   
Any assignment or sublease shall be made only if and shall not be
effective until the assignee or subtenant shall execute, acknowledge and
deliver to Landlord an agreement, in form and substance satisfactory to
Landlord, whereby the assignee or subtenant shall assume all of the obligations
of this Lease on the part of Tenant to be performed or observed and shall be
subject to all of the covenants, agreements, terms, provisions and conditions
contained in this Lease. 
Notwithstanding any such sublease or assignment and the acceptance of
rent or additional rent by Landlord from any subtenant or assignee, Tenant or
any guarantor shall and will remain fully liable for the payment of the rent
and additional rent due, and to become due hereunder, for the performance of
all of the covenants, agreements, terms, provisions and conditions contained in
this Lease on the part of Tenant to be performed and for all acts and omissions
of any licensee, subtenant, assignee or any other person claiming under or
through any subtenant that shall be in violation of any of the terms and
conditions of this Lease, and any such violation shall be deemed to be a
violation by Tenant.   Tenant shall
further indemnify, defend and hold Landlord harmless from and against any and
all losses, liabilities, damages, costs and expenses (including reasonable
attorney fees) resulting from any claims that may be made against Landlord by
the proposed assignee or subtenant or by any real estate brokers or other
persons claiming a commission or similar compensation in connection with the
proposed assignment or sublease.  20 
   D.      Effect of Default:    In
the event of Tenants default, Tenant hereby assigns all rents due from any
assignment or subletting to Landlord as security for performance of its obligations
under this Lease and Landlord may collect such rents as Tenants
Attorney-in-Fact, except that Tenant may collect such rents unless a default
occurs as described in paragraph 21 above. 
The termination of this Lease due to Tenants default shall not
automatically terminate any assignment or sublease then in existence.  At the election of Landlord, the assignee or
subtenant shall attorn to Landlord and Landlord shall undertake the obligations
of the Tenant under the sublease or assignment; provided the Landlord shall not
be liable for prepaid rent, security deposits or other defaults of the Tenant
to the subtenant or assignee, or any acts or omissions of Tenant, its agents,
employees or invitees.  29.      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 in Tenants reasonable opinion is sufficient for
continued occupation hereunder, this Lease shall as to the part so taken,
terminate as of the date title shall vest in the condemnor or purchaser, and
the Base Monthly Rent payable hereunder shall be adjusted so that the Tenant
shall be required to pay for the remainder of the Lease Term only such portion
of such rent as the value of the part remaining after such taking bears to the
value of the entire Premises prior to such taking.  If all of the Premises, or such part thereof be taken so that
there does not remain a portion reasonably sufficient 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 go to the Landlord and the Tenant shall have no claim thereto
but Landlord shall cooperate with Tenant to recover compensation for damage to
or taking of any Alterations or for Tenants moving costs. Tenant hereby waives
the provisions of California Code of Civil Procedures Section 1265.130 and any
other similarly enacted statue are waived by Tenant and the provisions of this
paragraph 29 shall govern in the case of such destruction.  30.      EFFECTS OF CONVEYANCE:   
The term Landlord as used in this Lease, means only the owner for the
time being of the land and Building, containing the Premises, so that, in the
event of any sale or other conveyance of said land or Building, or in the event
of a master Lease of the Building, the Landlord shall be and hereby is entirely
freed and relieved of all covenants and obligations of the Landlord hereunder,
and it shall be deemed and construed, without further agreement between the
parties and the purchaser at any such sale, or the master tenant of the
Building, that the purchaser or master tenant of the Building has assumed and
agreed to carry out any and all covenants and obligations of the Landlord
hereunder.  Landlord shall transfer and  21 
   deliver Tenants security deposit, to the purchaser at any such sale or
the master tenant of the Building, and thereupon the Landlord shall be
discharged from any further liability in reference thereto.  31.     SUBORDINATION:    In
the event Landlord notifies Tenant in writing, this Lease shall be subordinate
to any ground lease, deed of trust, or other hypothecation for security now or hereafter
placed upon the real property of which the Premises are a part and to any and
all advances made on the security thereof and to renewals, modifications,
replacements and extensions thereof. 
Tenant agrees to promptly execute and deliver any documents which may be
required to effectuate such subordination. 
Notwithstanding such subordination, Tenants right to quiet possession
of the Premises shall not be disturbed if Tenant is not in default and so long
as Tenant shall pay the rent and observe and perform all of the provisions of
this Lease.  At the request of any
lender, Tenant agrees to execute and deliver any reasonable modifications of
this Lease which do not materially adversely affect Tenants rights hereunder.  32.     WAIVER:   
The waiver by Landlord of any breach of any term, covenant or condition,
herein contained shall not be deemed to be a waiver of such term, covenant or
condition or any subsequent breach of the same or any other term, covenant or
condition herein contained.  The
subsequent acceptance of rent hereunder by Landlord shall not be deemed to be a
waiver of any preceding breach by Tenant of any term, covenant or condition of
this Lease, other than the failure of Tenant to pay the particular rental so
accepted, regardless of Landlords knowledge of such preceding breach at the
time of acceptance of such rent. No delay or omission in the exercise of any
right or remedy by Landlord shall impair such right or remedy or be construed
as a waiver thereof by Landlord. No act or conduct of Landlord, including,
without limitation, the acceptance of keys to the Premises shall constitute
acceptance of the surrender of the Premises by Tenant before the Expiration
Date. Landlords consent to or approval of any act by Tenant which require
Landlords consent or approvals shall not be deemed to waive or render
unnecessary Landlords consent to or approval of any subsequent act by Tenant.  33.     HOLDING OVER:   
Any holding over after the termination or Expiration Date, shall be
construed to be a tenancy from month to month terminable on thirty (30) days
written notice from either party and Tenant shall pay Base Monthly Rent to
Landlord at a rate equal to the greater of (i) one hundred fifty percent (150%)
of the Base Monthly Rent due in the month preceding the termination or
Expiration Date or (ii) one hundred fifty percent (150%) of the Fair Market
Rental (as defined in paragraph 36). Any holding over shall otherwise be on the
terms and conditions herein  22 
   specified, except those provisions relating to the Lease Term and any
options to extend or renew, which provisions shall be of no further force and
effect following the expiration of the applicable exercise period. Tenant shall
indemnify, defend, and hold Landlord harmless from all loss or liability
(including, without limitation, any loss or liability resulted from any claim
against Landlord made by any succeeding tenant) founded on or resulting from
Tenants failure to surrender the Premises and losses to Landlord due to lost
opportunities to lease the Premises to succeeding tenants, unless Landlord has
consented to such holding over.  34.     SUCCESSORS AND
ASSIGNS:    The covenants and conditions herein
contained shall, subject to the provisions of paragraph 27, apply to and bind
the heirs, successors, executors, administrators and assigns of all the parties
hereto; and all of the parties hereto shall be jointly and severally liable
hereunder.  35.     ESTOPPEL
CERTIFICATES:    Tenant shall at any time during the Lease
Term, within ten (10) business days following written notice from Landlord,
execute and deliver to Landlord 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 date to which the rent and other charges
are paid in advance, if any, and acknowledging that there are not, to Tenants
knowledge, any uncured defaults on the part of Landlord 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.  Tenants
failure to deliver such statement within such time shall be conclusive upon the
Tenant that:   (i) this Lease is in full
force and effect, without modification except as may be represented by
Landlord; (ii) there are not uncured defaults in Landlords performance.  Tenant also agrees to provide the most
current three (3) years of audited financial statements within ten (10)
business days of a request by Landlord for Landlords use in financing the
Premises with commercial lenders.  36.     OPTION
TO EXTEND THE LEASE TERM:  A.      Grant and
Exercise of Option:    Landlord hereby grants to Tenant, upon and
subject to the terms and conditions set forth in this paragraph, the option
(the Option) to extend the Lease Term for an additional term (the Option
Term), which Option Term shall be a period of thirty-six (36) months.  The Option Term shall be exercised, if at
all, by written notice to Landlord on or before the date that is nine (9)
months prior to the Expiration Date.  If
Tenant exercises the Option, each of the terms, covenants and conditions of
this Lease except this paragraph shall apply during the  23 
   Option Term as though the expiration date of the Option Term was the
date originally set forth herein as the Expiration Date, provided that the Base
Monthly Rent to be paid shall be the greater of (i) the Base Monthly Rent
applicable to the period immediately prior to the commencement of the Option
Term, or (ii) the Fair Market Rental, as hereinafter defined, for the Premises
for the Option Term. Anything contained herein to the contrary notwithstanding,
if Tenant is in monetary or material non-monetary default under any of the
terms, covenants or conditions of this Lease either at the time Tenant
exercises the Option or at any time thereafter prior to the commencement date
of the Option Term, Landlord shall have, in addition to all of Landlords other
rights and remedies provided in this Lease, the right to terminate the Option
upon notice to Tenant, in which event the expiration date of this Lease shall
be and remain the Expiration Date.  As
used herein, the term Fair Market Rental for the Premises shall mean the
rental and all other monetary payments including any escalations and
adjustments thereto (including without limitation Consumer Price Indexing) then
being obtained for new leases of space comparable in age and quality to the Premises
in the locality of the Building that Landlord could obtain during the Option
Term from a third party desiring to lease the Premises for the Option
Term.  Fair Market Rental shall further
take into account that (i) that Tenant is in occupancy of the Premises and
making functional use of the space in its then existing condition, and (ii)
that no brokerage commission is payable.  B.      Determination of Fair Market Rental:    If
Tenant exercises the Option, Landlord shall send to Tenant a notice setting
forth the Fair Market Rental for the Premises for the Option Term, on or before
the date that is one hundred fifty (150) days prior to the Expiration Date. If
Tenant disputes Landlords determination of the Fair Market Rental for the
Option Term, Tenant shall, within thirty (30) days after the date of Landlords
notice setting forth the Fair Market Rental for the Option Term, send to
Landlord a notice stating that Tenant either (i) elects to terminate its
exercise of the Option, in which event the Option shall lapse and this Lease
shall terminate on the Expiration Date, or (ii) disagrees with Landlords
determination of Fair Market Rental for the Option Term and elects to resolve
the disagreement as provided in paragraph 36(C) below.  If Tenant does not send to Landlord a notice
as provided in the previous sentence, Landlords determination of the Fair
Market Rental shall be the basis for determining the Base Monthly Rent to be
paid by Tenant hereunder during the Option Term.  If Tenant elects to resolve the disagreement as provided in
paragraph 36(C) below and such procedures shall not have been concluded prior
to the commencement date of the Option Term, Tenant shall pay Base Monthly Rent
to Landlord hereunder adjusted to reflect the Fair Market Rental as determined
by Landlord in the manner provided above. 
If the amount of Fair Market Rental as finally determined pursuant to in
paragraph 36(C) below is greater than Landlords determination, Tenant shall
pay to Landlord the difference  24 
   between
the amount paid by Tenant and the Fair Market Rental as so determined in
paragraph 36(C) below within thirty (30) days after the determination.  If the Fair Market Rental as finally
determined in paragraph 36(C) below is less than Landlords determination, the
difference between the amount paid by Tenant and the Fair Market Rental as so
determined in paragraph 36(C) below shall be credited against the next
installments of rent due from Tenant to Landlord hereunder.  C.      Resolution
of a Disagreement overthe Fair Market Rental:   Any
disagreement regarding the Fair Market Rental shall be resolved as follows:  1.        Within
thirty (30) days after Tenants response to Landlords notice to Tenant of the
Fair Market Rental, Landlord and Tenant shall meet no less than two (2) times,
at a mutually agreeable time and place, to attempt to resolve any such
disagreement.  2.        If
within the thirty (30) day period referred to in (i) above, Landlord and Tenant
can not reach agreement as to the Fair Market Rental, they shall each select
one appraiser to determine the Fair Market Rental.  Each such appraiser shall arrive at a determination of the Fair
Market Rental and submit their conclusions to Landlord and Tenant within thirty
(30) days after the expiration of the thirty (30) day consultation period
described in (i) above.  3.        If
only one appraisal is submitted within the requisite time period, it shall be
deemed to be the Fair Market Rental. If both appraisals are submitted within
such time period, and if the two appraisals so submitted differ by less than
ten percent (10%) of the higher of the two, the average of the two shall be the
Fair Market Rental.  If the two
appraisals differ by more than ten percent (10%) of the higher of the two, then
the two appraisers shall immediately select a third appraiser who shall within
thirty (30) days after his or her selection make a determination of the Fair
Market Rental and submit such determination to Landlord and Tenant. This third
appraisal will then be averaged with the closer of the two previous appraisals
and the result shall be the Fair Market Rental.  4.        All
appraisers specified pursuant to this paragraph shall be members of the
American Institute of Real Estate Appraisers with not less than ten (10) years
experience appraising office and industrial properties in the Santa Clara
Valley.  Each party shall pay the cost
of the appraiser selected by such party and one-half of the cost of the third
appraiser plus one-half of any other costs incurred in resolving the dispute
pursuant to this paragraph.  25 
   37.     OPTIONS:   
All Options provided Tenant in this Lease are personal and granted to
original Tenant or its affiliates and are not exercisable by any third party
should Tenant assign or sublet all or a portion of its rights under this Lease,
unless Landlord consents to permit exercise of any option by any assignee or
subtenant, in Landlords sole discretion.  
In the event that Tenant hereunder has any multiple options to extend
this Lease, a later option to extend the Lease cannot be exercised unless the
prior option has been so exercised.  38.     QUIET ENJOYMENT:   
Upon Tenants faithful and timely performance of all the terms and
covenants of the Lease, Tenant shall quietly have and hold the Premises for the
Lease Term and any extensions thereof.  39.     BROKERS:   
Tenant represents it has not utilized or contacted a real estate broker
or finder with respect to this Lease other than CRESA Partners (Broker) and
Tenant agrees to indemnify and hold Landlord harmless against any claim, cost,
liability or cause of action asserted by any other broker or finder claiming
through Tenant.  Landlord shall be
responsible for payment of a real estate commission to Broker pursuant to a
separate agreement between Landlord and Broker.  40.     This section intentionally left blank  41.     AUTHORITY OF
PARTIES:    Each individual executing this Lease on
behalf of Tenant represents and warrants that he is duly authorized to execute
and deliver this Lease on behalf of the corporation, in accordance with a duly
adopted resolution of the Board of Directors of said corporation or in
accordance with the by-laws of said corporation, and that this Lease is binding
upon said corporation in accordance with its terms.  Each individual executing this Lease on behalf of Landlord
represents and warrants that he is duly authorized to execute and deliver this
Lease on behalf of the limited partnership and that this Lease is binding upon
said limited partnership in accordance with its terms.  42.     MISCELLANEOUS
PROVISIONS:  A.       Rent:   
All monetary sums due from Tenant to Landlord under this Lease shall be
deemed to be rent.  B.       Management Fee:   
All maintenance and utility services administered by Landlord  26 
   and
subject to reimbursement by Tenant shall include a property management fee to
Landlord of fifteen percent (15%).  C.       Performance
by Landlord:    If Tenant fails to perform any obligation
required under this Lease or by law or governmental regulation after the
expiration of any applicable notice and cure period, Landlord in its sole
discretion may without notice perform such obligation, in which event Tenant
shall pay Landlord as additional rent all sums paid by Landlord in connection
with such substitute performance within ten (10) days following receipt of
Landlords written invoice for such payment.  D.       Interest:   
All sums due hereunder, including rent and additional rent, if not paid
when due, shall bear interest at the maximum rate permitted under California
law accruing from the date due until the date paid to Landlord.  E.        Rights and
Remedies:    All rights and remedies hereunder are
cumulative and not alternative to the extent permitted by law and are in
addition to all other rights and remedies in law and in equity.  F.        Survival
of Indemnities:    All indemnification, defense, and hold
harmless obligations of Landlord and Tenant under the Lease shall survive the
expiration or sooner termination of the Lease.  G.       Severability:    If
any term or provision of this Lease is held unenforceable or invalid by a court
of competent jurisdiction, the remainder of the Lease shall not be invalidated
thereby but shall be enforceable in accordance with its terms, omitting the
invalid or unenforceable term.  H.      Choice of Law:   
This Lease shall be governed by and construed in accordance with
California law.  I.        Time:    Time is of the essence hereunder.  J.       Entire Agreement:   
This instrument contains all of the agreements and conditions made
between the parties hereto and may not be modified orally or in any other
manner than by an agreement in writing signed by all of the parties hereto or
their respective successors in interest.  27 
   K.      Representations:   
Tenant acknowledges that neither Landlord or its affiliates or agents
have made any agreements, representations, warranties or promises with respect
to the demised Premises or the Building of which they are a part, or with
respect to present or future rents, expenses, operations, tenancies or any
other matter. Except as herein expressly set forth herein, Tenant relied on no
statement of Landlord or its agents for that purpose.  L.      Headings:   
The headings or titles to the paragraphs of this Lease are not a part of
this Lease and shall have no effect upon the construction or interpretation of
any part thereof.  IN WITNESS WHEREOF, Landlord and Tenant have executed these
presents, the day and year first above written.  LANDLORD: Sobrato Interests,
  TENANT: Affymetrix, Inc.a
  California limited partnership
  a
  California corporationBY:
  /s/ John M. Sobrato
  
  BY:
  /s/Barbara
  A. CaulfieldITS:
  GENERAL PARTNER
  
  ITS:
  BarbaraA.
  Caulfield
  Exec. V.P. and General Counsel   28 
   EXHIBIT APremises  [BUILDING MAP]