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                                                                   EXHIBIT 10.17


                                 LEASE AGREEMENT


         1. Parties. This Lease, dated for reference purposes only as July 1,
1996, is made by and between LOGUE INVESTMENTS, L.P., a California limited
partnership ("Landlord"), and MICROCIDE PHARMACEUTICALS, INC., a Delaware
corporation ("Tenant").

         2. Demise of Premises. Landlord hereby leases to Tenant and Tenant
hereby leases from Landlord, upon the terms and conditions hereinafter set
forth, those certain premises (the "Premises") situated in Mountain View, County
of Santa Clara, State of California, described as follows:

                  A. That Parcel of real property more particularly described in
EXHIBIT "A" attached hereto (the "Parcel");

                  B. That certain building located at 320 Logue Ave., Mountain
View, California 94043 on the Parcel as shown on the site plan attached hereto
as EXHIBIT "B" containing approximately 31, 000 square feet (the "Building").

                  C. The improvements (the "Tenant Improvements") to be
constructed in and about the Building in accordance with the provisions of the
Improvement Agreement attached hereto as EXHIBIT "C" (the "Improvement
Agreement").

         The Building and the Tenant Improvements are collectively referred to
in this Lease as the "Improvements".


         3. Lease Term.

                  A. Lease Term. The term of this Lease ("Lease Term") shall be
for eight (8) years eleven (11) months, commencing on November 1, 1996 (the
"Commencement Date") and ending on September 30, 2005 unless sooner terminated
pursuant to any provision hereof.

                  B. Early Entry. Upon mutual execution and delivery of this
Lease, Tenant may enter the Premises to install Tenant Improvements and fixtures
and equipment therein. Such entry shall be subject to all of the terms and
conditions of this Lease (including, without limitation, the obligations to
maintain insurance and pay for utilities), excepting only the obligation to pay
the Monthly Installment of rent and Additional Rent. Tenant shall coordinate its
entry onto the Premises with Landlord and the contractors and other personnel
employed by Landlord. Tenant shall at all times while exercising its right of
entry, refrain from interfering with the construction activities of Landlord's
personnel. In any case, Tenant shall repair any damage to the Improvements
constructed by Landlord resulting from the entry upon the Premises by Tenant or
Tenant's Agents prior to the Commencement

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Date or caused by the installation of fixtures and equipment by Tenant or
Tenant's Agents. If the entry by Tenant or Tenant's Agents upon the Premises
prior to the Commencement Date interferes with Landlord's construction
activities, then Landlord shall give Tenant written notice requesting that
Tenant cease such interference.


         4. Rent.

                  A. Time of Payment. Tenant shall pay to Landlord as rent for
the Premises the respective sums specified in Subparagraph 4.B below (the
"Monthly Installment") each month in advance on the first day of each calendar
month, without deduction or offset, prior notice or demand, commencing on the
Commencement Date and continuing through the Lease Term, together with such
additional rents as are payable by Tenant to Landlord under the terms of this
Lease. The Monthly Installment for any period during the Lease Term which is
less than one (1) full month shall be a pro rata portion of the Monthly
Installment based upon a thirty (30) day month.

                  B. Monthly Installment. The Monthly Installment of rent shall
be the following respective amounts during the following respective time
periods:




                  LEASE YEAR             MONTHLY INSTALLMENT
                  ----------             -------------------
                                    
              11/01/96-10/31/97        $ 32,550.00    month NNN
              11/01/97-10/31/98        $ 34,100.00    month NNN
              11/01/98-10/31/99        $ 35,650.00    month NNN
              11/01/99-10/31/00        $ 37,200.00    month NNN
              11/01/00-10/31/01        $ 38,750.00    month NNN
              11/01/01-10/31/02        $ 40,300.00    month NNN
              11/01/02-10/31/03        $ 41,850.00    month NNN
              11/01/03-10/31/04        $ 43,400.00    month NNN
              11/01/04-09/30/05        $ 44,950.00    month NNN


                  C. Tenant Improvement Allowance. Landlord shall make available
for the payment of a portion of the costs of the Improvements (the "TI Costs")
an amount equal to three hundred eighty seven thousand five hundred dollars
($387,500.00) (the "TI Allowance") . Landlord shall disburse the TI Allowance
to Tenant in monthly progress payments based upon percentage of completion of

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the Tenant Improvements. Each monthly progress payment shall be disbursed within
ten (10) days after Landlord's receipt of (i) written invoice from Tenant
showing amounts incurred by Tenant for TI Costs during the preceding month and
the percentage of completion of the Tenant Improvements to date together with
supporting invoices from Tenant's contractor; and (ii) lien releases from
Tenant's contractors and subcontractors with respect to work covered by the
previous disbursements. In no event shall the aggregate amount to be paid by
Landlord for TI Costs exceed the TI Allowance. Tenant shall be responsible for
completing and paying in cash for all the Improvements except for those
specified in the Improvement Agreement (as described in Exhibit "C") as being
the responsibility of Landlord.

                  D. Late Charge. Tenant acknowledges that late payment by
Tenant to Landlord of 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,
processing and accounting charges, and late charges which may be imposed on
Landlord by the terms of any mortgage or deed of trust covering the Premises.
Accordingly, if any installment of rent or any other sum due from Tenant shall
not be received by Landlord within five (5) days after such amount has not been
paid when due, then Tenant shall pay to Landlord, as additional rent, a late
charge equal to six percent (6%) of such overdue amount. 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 its other rights and remedies granted hereunder.

                  E. Additional Rent. All taxes, insurance premiums, late
charges, costs, expenses and other sums which Tenant is required to pay under
this Lease, together with all interest and penalties that may accrue thereon in
the event of Tenant's failure to pay such amounts, and all reasonable damages,
costs, and attorneys, fees and expenses which Landlord may incur by reason of
any default of Tenant or failure on Tenant's part to comply with the terms of
this Lease, shall be deemed to be additional rent ("Additional Rent") and shall
be paid in addition to the Monthly Installment of rent, and, in the event of
nonpayment by Tenant, Landlord shall have all of the rights and remedies with
rent. All items of Additional Rent which are to be paid directly by Tenant to
respect thereto as Landlord has for the nonpayment of the Monthly Installment of
Landlord shall include an additional five percent (5%) of such items of
Additional Rent in order to compensate Landlord for accounting, management and
processing services.


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                  F. Place of Payment. Rent shall be payable in lawful money of
the United States of America to Landlord at 2680 North First Street, Suite 280,
San Jose, California 95134 or to such other person(s) or at such other place(s)
as Landlord may designate in writing.

                  G. Advance Payment - Concurrently with the execution of this
Lease, Tenant shall pay to Landlord the sum of Thirty Two Thousand Five Hundred
Fifty Dollars ($32,550.00) to be applied to the Monthly Installment of rent
first accruing under this Lease.

         5. Security Deposit. Tenant shall deposit the sum of Thirty Two
Thousand Five Hundred Fifty Dollars ($32,550.00) (the "Security Deposit") upon
execution of this Lease, to secure the faithful performance by Tenant of each
term, covenant and condition of this Lease. If Tenant shall at any time fail to
make any payment or fail to keep or perform any term, covenant or condition on
its part to be made or performed or kept under this Lease, Landlord may, but
shall not be obligated to and without waiving or releasing Tenant from any
obligation under this Lease, use, apply or retain the whole or any part of the
Security Deposit (A) to the extent of any sum due to Landlord; (B) to make any
required payment on Tenant's behalf; or (C) to compensate Landlord for any loss,
damages, attorneys' fees or expense sustained by Landlord due to Tenant's
default. In such event, Tenant shall, within five (5) days of written demand by
Landlord, remit to Landlord sufficient funds to restore the Security Deposit to
its original sum. No interest shall accrue on the Security Deposit. Landlord
shall not be required to keep the Security Deposit separate from its general
funds. The Security Deposit, less any sums owing to Landlord or which Landlord
is otherwise entitled to retain, shall be returned to Tenant within thirty (30)
days after the termination of this Lease and vacancy of the Premises by Tenant.

         6. Use of Premises.

                  A. Restrictions on Use. Tenant shall use the Premises only in
conformance with the CC&R's (as defined below) and applicable governmental laws,
regulations, rules and ordinances for the purpose of biotech research and
development, manufacturing, laboratory use and for no other purpose without the
consent of Landlord. Tenant shall indemnify, defend and hold Landlord harmless
against any loss, expense, damage, attorneys' fees or liabilities arising out of
the failure of Tenant to comply with the CC&R's and/or any Law regulating
Tenant's use of the Premises. Tenant shall not commit or suffer to be committed,
any waste upon the Premises, or any nuisance, or other acts or things which may
disturb the quiet enjoyment of any other tenant in the buildings adjacent to the
Premises, or allow any sale by auction upon the Premises, or allow the Premises
to be used for any unlawful purpose, or place any loads upon the floor, walls or
ceiling which

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would endanger the structure, or place any harmful liquids in the drainage
system of the Premises. No waste materials or refuse shall be dumped upon or
permitted to remain upon any part or the Premises outside of the Building,
except in trash containers placed inside exterior enclosures designated for that
purpose by Landlord. No materials, supplies, finished products or semifinished
products, raw materials, or articles of any nature shall be stored upon
or permitted to remain on any portion of the Parcel outside of the Building.
Tenant may be permitted to have equipment stored with permission from owner
whose permission will not be unreasonably withheld. Tenant shall strictly
comply with the provisions of Paragraph 37 below.

                  B. Initial Occupancy. Tenant shall be obligated to take
possession and enter into occupancy of the Premises within thirty (30) days
following the Commencement Date.

         7. Taxes and Assessments.

                  A. Tenant's Property. Tenant shall pay before delinquency any
and all taxes and assessments, license fees and public charges levied, assessed
or imposed upon or against Tenant Is fixtures, equipment, furnishings,
furniture, appliances and personal property installed or located on or within
the Premises. Tenant shall use its best efforts to cause said fixtures,
equipment, furnishings, furniture, appliances and personal property to be
assessed and billed separately from the real property of Landlord. If any of
Tenant's said personal property shall be assessed with Landlord's real property,
Tenant shall pay Landlord the taxes attributable to Tenant within ten (10) days
after receipt of a written statement from Landlord setting forth the taxes
applicable to Tenant's property.

                  B. Property Taxes. Tenant shall pay, as Additional Rent, one
hundred percent (100%) of all Property Taxes levied or assessed with respect to
the Premises which become due or accrue during the term of this Lease. Tenant
shall pay such Property Taxes to Landlord not later than (i) ten (10) days prior
to the delinquency date of such Property Taxes, or (ii) twenty (20) days after
receipt of billing, whichever is later. If Tenant fails to do so, Tenant shall
reimburse Landlord, on demand, for all interest, late fees and penalties that
the taxing authority charges Landlord. In the event Landlord's Lender holding a
first priority lien requires an impound for Property Taxes, then on the first
day of each month during the Lease Term, Tenant shall pay Landlord one twelfth
(1/12) of the annual Property Taxes. Tenant's liability hereunder shall be
prorated to reflect the commencement and termination dates of this Lease.

                  C. Property Taxes Defined. For the purpose of this Lease,
"Property Taxes" means and includes all taxes, assessments (including, but not
limited to, assessments for public improvements or benefits), taxes based on
vehicles utilizing parking areas,


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taxes based or measured by the rent paid, payable or received under this Lease,
taxes on the value, use, or occupancy of the Premises, the Building and/or the
Parcel, and all other governmental impositions and charges of every kind and
nature whatsoever, whether or not customary or within the contemplation of the
parties hereto and regardless of whether the same shall be extraordinary or
ordinary, general or special, unforeseen or foreseen, or similar or dissimilar
to any of the foregoing which, at any time during the Lease Term, shall be
applicable to the Premises, the Building and/or the Parcel or assessed, levied
or imposed upon the Premises the Building and/or the Parcel, or become due and
payable and a lien or charge upon the Premises, the Building and/or the Parcel,
or any part thereof, under or by virtue of any present or future laws, statutes,
ordinances, regulations or other requirements of any governmental authority
whatsoever. The term "Property Taxes" shall not include any federal, state or
local net income, estate, gift, transfer or inheritance tax imposed on Landlord.

                  D. Other Taxes. Tenant shall, as Additional Rent, pay or
reimburse Landlord for any tax based upon, allocable to, or measured by the area
of the Premises or the Building or the Parcel; any tax upon or with respect to
the possession, leasing, operation, management, maintenance, alteration, repair,
use or occupancy of the Premises or any portion thereof; any privilege tax,
excise tax, business and occupation tax, gross receipts tax, sales and/or use
tax, water tax, sewer tax, employee tax, occupational license tax imposed upon
Landlord or Tenant with respect to the Premises; any tax upon this transaction
or any document to which Tenant is a party creating or transferring an interest
or an estate in the Premises. This Paragraph 7.D shall not obligate Tenant to
pay any federal, state or local net income tax, estate, transfer or inheritance
tax imposed on Landlord.

         8. Insurance.

                  A. Indemnity. Tenant agrees to indemnify, protect and defend
Landlord against and hold Landlord harmless from any and all claims, causes of
action, judgments, obligations or liabilities, and all reasonable expenses
incurred in investigating or resisting the same (including reasonable attorneys,
fees), on account of, or arising out of, the operation, maintenance, use or
occupancy of the Premise by Tenant and/or its Agents (except for the active
negligence or willful misconduct of Landlord or its Agents). This Lease is made
on the express understanding that Landlord shall not be liable for, or suffer
loss by reason of, injury to person or property, from whatever cause (except for
the active negligence or willful misconduct of Landlord or its Agents and any
default by Landlord of its obligations under this Lease), which in any way may
be connected with the operation, maintenance, use or occupancy of the Premises
by Tenant and/or its Agents specifically including,


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without limitation, any liability for injury to the person or property of Tenant
or its Agents.

                  B. Liability Insurance. Tenant shall, at Tenant's expense,
obtain and keep in force during the term of this Lease a policy of comprehensive
public liability insurance insuring Landlord and Tenant against claims and
liabilities arising out of the operation, maintenance, use, or occupancy of the
Premises. Such insurance shall provide combined single limit coverage of not
less than Five Million Dollars ($5,000,000.00) per occurrence. Landlord shall
have the right to require Tenant to increase the amount of coverage of such
public liability insurance to the extent reasonably necessary to bring such
insurance coverage into conformity with the level of coverage commonly carried
by similar businesses in California, which right Landlord may exercise no more
frequently than once every two (2) years during the lease term. The insurance
shall be provided by companies with an A.M. Best rating of A+, XII or better.
Tenant shall deliver to Landlord, prior to possession, and at least thirty (30)
days prior to the expiration thereof, a certificate of insurance evidencing the
existence of the policy required hereunder and such certificate shall certify
that the policy (1) names Landlord as an additional insured, (2) shall not be
canceled or altered without thirty (30) days prior written notice to Landlord,
(3) insures performance of the indemnity set forth in Subparagraph 8.A above,
(4) the coverage is primary and any coverage by Landlord is in excess thereto
and (5) contains a cross-liability endorsement.

         Landlord may maintain a policy or policies of comprehensive general
liability insurance insuring Landlord (and such others as are designated by
Landlord) , against liability for personal injury, bodily injury, death and
damage to property occurring or resulting from an occurrence in, on or about the
Premises, with such limits of coverage as Landlord may from time to time
determine are reasonably necessary for its protection. Tenant shall, as
Additional Rent, reimburse Landlord for the cost of any such insurance policy
within ten (10) days after receipt of billing.

                  C. Property Insurance. Landlord shall, at Tenant's expense,
obtain and keep in force during the Lease Term a policy of insurance covering
loss or damage to the Building and Tenant Improvements, in the amount of the
full replacement value thereof with Agreed Amount Endorsement, providing
protection against those perils included within the classification of "all risk"
and/or special form" insurance, plus a policy of rental income insurance in the
amount of one hundred percent (100%) of twelve (12) months' rent (including,
without limitation, sums payable as Additional Rent), together with such
additional coverages (such as earthquake and/or flood insurance) which Landlord
may elect to maintain from time to time or which may be required from time to
time by Landlord's Lender. Tenant shall have no interest in nor any right

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to the proceeds of any insurance procured by Landlord on the Building and Tenant
Improvements. Tenant shall pay to Landlord, as Additional Rent, the cost of such
insurance procured and maintained by Landlord on an annual basis within ten (10)
days after receipt of demand therefore from Landlord. Tenant's liability for the
cost of such insurance shall be pro rated as of the commencement and termination
of the Lease Term. Tenant acknowledges that such insurance procured by Landlord
shall contain a deductible which reduces Tenant's cost for such insurance and,
in the event of loss or damage, Tenant shall be required to pay to Landlord the
amount of such deductible. If acceptable to Landlord's insurance carrier, Tenant
shall maintain the casualty insurance on Tenant's Property (as defined in
Paragraph 32 below).

                  D. Tenant's Personal Property Insurance. Tenant acknowledges
that the insurance to be maintained Landlord on the Premises pursuant to
Paragraph 8.C above will not insure any of Tenant's property. Accordingly,
Tenant, at Tenant's own expense, shall maintain in full force and effect on all
of its fixtures, equipment and personal property in the Premises, a policy of
"All Risk" coverage insurance to the extent of at least ninety percent (90%) of
their insurable value.

                  E. Mutual Waiver of Subrogation. Tenant and Landlord hereby
mutually waive their respective rights of recovery against each other of any
loss of or damage to the property of either party, to the extent such loss or
damage is insured by any insurance policy required to be maintained by this
Lease (or would be insured if such insurance policy was actually maintained) or
otherwise in force at the time of such loss or damage. Each party shall obtain
any special endorsements, if required by the insurer, whereby the insurer waives
its right of subrogation against the other party hereto. The provisions of this
Subparagraph 8.E shall not apply in those instances in which the waiver of
subrogation would cause either party's insurance coverage to be voided or
otherwise made uncollectable.

         9. Utilities. Tenant shall pay for all water, gas, light, heat, power,
electricity, telephone, trash pick-up, sewer charges, and all other services
supplied to or consumed on the Premises, and all taxes and surcharges thereon.

         10. Repairs and Maintenance.

                  A. Landlord's Repairs. Subject to the provisions of Paragraph
14, Landlord, at its expense, shall keep and maintain the structural elements
and exterior walls of the Building in good order and repair. Landlord shall not,
however, be required to maintain, repair or replace the interior surface of
exterior walls, nor shall Landlord be required to maintain, repair or replace
windows, doors, skylights or plate glass. Landlord shall have no

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obligation to make repairs under this Subparagraph 10.A until a reasonable time
after receipt of written notice from Tenant of the need for such repairs.
Notwithstanding the foregoing, Tenant shall reimburse Landlord, as Additional
Rent, within fifteen (15) days after receipt of billing, for the cost of
maintenance and repairs of the exterior walls and structural elements of the
Building to the extent such maintenance or repair is required because of the
negligence or willful misconduct of Tenant or Agents. As used herein, the term
"structural elements of the Building" shall mean and be limited to the
structural walls, foundations, footings, floor slab (but not flooring), and roof
structure (but not roofing or roof membrane).

                  B. Tenant's Repairs. Except as expressly provided in
Subparagraph 10.A above and Paragraphs 14 and 15 below, Tenant shall, at its
sole cost, keep and maintain the entire Premises and every part thereof,
including without limitation, the windows, window frames, plate glass, glazing,
skylights, truck doors, doors and all door hardware, the interior walls and
partitions, interior surfaces of exterior walls, carpets, flooring, roofing,
roof membrane, gutters, down spouts, the electrical, plumbing, lighting,
heating, ventilating and air conditioning systems and equipment, and all areas
outside the Building (including all landscaping, irrigation systems, paving,
driveways, parking areas, sidewalks, fences, signs and exterior lighting) in
good order, condition and repair. The term "repair" shall include replacements,
restorations and/or renewals when necessary as well as painting. Tenant's
obligation shall extend to all alterations, additions and improvements to the
Premises, and all fixtures and appurtenances therein and thereto. Tenant shall,
at all times during the Lease Term, have in effect a service contract for the
maintenance of the heating, ventilating and air conditioning ("HVAC") equipment
with an HVAC repair and maintenance contractor reasonably approved by Landlord.
The HVAC service contract shall provide for periodic inspection and servicing at
least once every three (3) months during the term hereof, and Tenant shall
provide Landlord with a copy of such contract and all periodic service reports.
Landlord shall assign to Tenant for the term of this Lease the benefit of all
warranties available to Landlord which would reduce the cost of performing the
obligations of Tenant to make repairs under this Subparagraph 1O.B. Landlord
shall cooperate with Tenant in the enforcement of such warranties.

         Should Tenant fail to commence to make repairs required of Tenant
hereunder within ten (10) days after notice from Landlord or should Tenant fail
thereafter to diligently complete the repairs, Landlord, in addition to all
other remedies available hereunder or by law and without waiving any alternative
remedies, may make the same, and in that event, Tenant shall reimburse Landlord
as additional rent for the cost of such maintenance or repairs within ten (10)
days of written demand by Landlord.

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                  C. Replacement of Roof Membrane and/or HVAC Compressor.
Notwithstanding anything in Subparagraphs 10.A or 10.B above to the contrary, if
the roof membrane of the Building requires replacement during the Lease Term,
then Landlord shall perform such replacement and Tenant shall pay to Landlord,
within fifteen (15) days after receipt of billing, as Additional Rent, a
fraction of the cost of such replacement, which fraction shall have as its
numerator the number of calendar months then remaining in the Lease Term at the
time of such replacement and shall have as its denominator one hundred eighty
(180) months. Notwithstanding anything in Subparagraphs 10.A or 10.B to the
contrary, if an HVAC compressor requires replacement during the Lease Term, then
Landlord shall perform such replacement and Tenant shall pay to Landlord, within
fifteen (15) days after receipt of billing, as Additional Rent, a fraction of
the cost of such replacement, which fraction shall have as its numerator the
number of calendar months then remaining in the Lease Term at the time of such
replacement and shall have as its denominator one hundred twenty (120) months.

                  D. Waiver. Landlord shall have no maintenance or repair
obligations whatsoever with respect to the Premises except as expressly provided
in Subparagraph 10.A and Paragraph 14. Tenant hereby expressly waives the
provisions of Subsection 1 of Section 1932 and Sections 1941 and 1942 of the
Civil Code of California and all rights to make repairs at the expense of
Landlord as provided in Section 1942 of said Civil Code.

         11. Alterations.

                  A. Limitations. Tenant shall not make, or suffer to be made,
any alterations, improvements or additions in, on, about or to the Premises or
any part thereof, without the prior written consent of Landlord (which consent
shall not be unreasonably withheld) and without a valid building permit issued
by the appropriate governmental authority; provided, however Landlord's consent
shall not be required for interior nonstructural alterations which cost less
than Ten Thousand Dollars ($10,000.00) per work of improvement so long as
Tenant provides Landlord with copies of plans and applicable permits prior to
commencing construction of such alterations. As a condition to, and concurrently
with, the giving of such consent Landlord may require that Tenant agree to
remove any such alterations, improvements or additions at the termination of
this Lease, and to restore the Premises to their prior condition. Unless
Landlord requires that Tenant remove any such alteration, improvement or
addition, any alteration, addition or improvement to the Premises, except
movable furniture and trade fixtures, shall become the property of Landlord upon
termination of the Lease and shall remain upon and be surrendered with the
Premises at the termination of this Lease. Without limiting the generality of
the foregoing, all heating, lighting, electrical (including all wiring, conduit,
outlets,

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drops, buss ducts, main and subpanels), air conditioning, partitioning, drapery,
and carpet installations made by Tenant regardless of how affixed to the
Premises, together with all other additions, alterations and improvements that
have become an integral part of the Building, shall be and become the property
of the Landlord upon termination of the Lease, and shall not be deemed trade
fixtures, and shall remain upon and be surrendered with the Premises at the
termination of this Lease.

                  B. Alterations Required by Law. if, during the term hereof,
any alteration, addition or change of any sort to all or any portion of the
Premises is required by Law, Tenant shall promptly make the same at its sole
cost and expense.

         12. Acceptance of the Premises. By entry and taking possession of the
Premises pursuant to this Lease, Tenant accepts the Premises as being in good
and sanitary order, condition and repair and accepts the Premises in their
condition existing as of the date of such entry and Tenant further accepts the
Tenant Improvements to be constructed by Landlord, if any, as being completed in
accordance with the plans and specifications for such Tenant Improvements,
except for punch list items. Tenant acknowledges that neither the Landlord nor
Landlord, s agents has made any representation or warranty as to the suitability
of the Premises to the conduct of Tenant's business. Any agreements, warranties
or representations not expressly contained herein shall in no way bind either
Landlord or Tenant, and Landlord and Tenant expressly waive all claims for
damages by reason of any statement, representation, warranty, promise or
agreement, if any, not contained in this Lease. This Lease constitutes the
entire understanding between the parties hereto and no addition to, or
modification of, any term or provision of this Lease shall be effective until
set forth in a writing signed by both Landlord and Tenant.

         13. Default.

                  A. Events of Default. A breach of this Lease by Tenant shall
exist if any of the following events (hereinafter referred to as "Event of
Default") shall occur:

                            (1) Default in the payment when due of any
installment of rent or other payment required to be made by Tenant hereunder,
where such default shall not have been cured within three (3) days after written
notice of such default is given to Tenant;

                            (2) Tenant's failure to perform any other term,
covenant or condition contained in this Lease where such failure shall have
continued for twenty (20) days after written notice of such failure is given to
Tenant; provided, however, Tenant shall not be deemed in default if Tenant
commences to cure such failure

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within said twenty (20) day period and thereafter diligently prosecutes such
cure to completion;

                            (3) Tenant's abandonment of the Premises;

                            (4) Tenant's assignment of its assets for the
benefit of its creditors;

                            (5) The sequestration of, attachment of, or
execution on, any substantial part of the property of Tenant or on any property
essential to the conduct of Tenant's business, shall have occurred and Tenant
shall have failed to obtain a return or release of such property within sixty
(60) days thereafter, or prior to sale pursuant to such sequestration,
attachment or levy, whichever is earlier;

                            (6) Tenant or any guarantor of Tenant Is obligations
hereunder shall commence any case, proceeding or other action seeking
reorganization, arrangement, adjustment, liquidation, dissolution or composition
of it or its debts under any law relating to bankruptcy, insolvency,
reorganization or relief of debtors, or seek appointment of a receiver, trustee,
custodian, or other similar official for it or for all or any substantial part
of its property;

                            (7) Tenant or any such guarantor shall take any
corporate action to authorize any of the actions set forth in Clause 6 above; or

                            (8) Any case, proceeding or other action against
Tenant or any guarantor of Tenant's obligations hereunder shall be commenced
seeking to have an order for relief entered against it as debtor, or seeking
reorganization, arrangement, adjustment, liquidation, dissolution or composition
of it or its debts under any law relating to bankruptcy, insolvency,
reorganization or relief of debtors, or seeking appointment of a receiver,
trustee, custodian or other similar official for it or for all or any
substantial part of its property, and such case, proceeding or other action (i)
results in the entry of an order for relief against it which is not fully stayed
within thirty (30) days after the entry thereof or (ii) remains undismissed for
a period of ninety (90) days.

         B. Remedies. Upon any Event of Default, Landlord shall have the
following remedies, in addition to all other rights and remedies provided by
law, to which Landlord may resort cumulatively, or in the alternative:

                            (1) Recovery of Rent. Landlord shall be entitled to
keep this Lease in full force and effect (whether or not Tenant shall have
abandoned the Premises) and to enforce all of its rights

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and remedies under this Lease, including the right to recover rent and other
sums as they become due, plus interest at the Permitted Rate (as defined in
Paragraph 31 below) from the due date of each installment of rent or other sum
until paid.

                            (2) Termination. Landlord may terminate this Lease
by giving Tenant written notice of termination. On the giving of the notice all
of Tenant's rights in the Premises shall terminate. Upon the giving of the
notice of termination, Tenant shall surrender and vacate the Premises in the
condition required by Paragraph 32, and Landlord may re-enter and take
possession of the Premises and all the remaining improvements or property and
eject Tenant or any of Tenant's subtenants, assignees or other person or persons
claiming any right under or through Tenant or eject some and not others or eject
none. This Lease may also be terminated by a judgment specifically providing for
termination. Any termination under this paragraph shall not release Tenant from
the payment of any sum then due Landlord or from any claim for damages or rent
previously accrued or then accruing against Tenant. In no event shall any one or
more of the following actions by Landlord constitute a termination of this
Lease:

                                    (a) maintenance and preservation of the
Premises;

                                    (b) efforts to relet the Premises;

                                    (c) appointment of a receiver in order to
protect Landlord's interest hereunder;

                                    (d) consent to any subletting of the
Premises or assignment of this Lease by Tenant, whether pursuant to provisions
hereof concerning subletting and assignment or otherwise; or

                                    (e) any other action by Landlord or
Landlord's agents intended to mitigate the adverse effects from any breach of
this Lease by Tenant.

                            (3) Damages. In the event this Lease is terminated
pursuant to Subparagraph 13.B(2) above, or otherwise, Landlord shall be entitled
to damages in the following sums:

                                    (a) the worth at the time of award of the
unpaid rent which has been earned at the time of termination; plus

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

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

                                    (d) any other amount necessary to compensate
Landlord for all detriment proximately caused by Tenant's failure to perform
Tenant's obligations under this Lease, or which in the ordinary course of things
would be likely to result therefrom including, without limitation, the
following: (i) expenses for cleaning, repairing or restoring the Premises; 
(ii) real estate broker's fees, advertising costs and other expenses of 
re-leasing the Premises which are fairly allocable to the remainder of the 
Lease Term; (iii) expenses in retaking possession of the Premises; and (iv) 
attorneys' fees and court costs.

                                    (e) The "worth at the time of award" of the
amounts referred to in Subparagraphs (a) and (b) of this Paragraph 13.B(3), is
computed by allowing interest at the Permitted Rate. The "worth at the time of
award" of the amounts referred to in Subparagraph (c) of this Paragraph 13.B(3)
is computed by discounting such amount at the discount rate of the Federal
Reserve Board of San Francisco at the time of award plus one percent (1%). The
term "rent" as used in this Paragraph 13 shall include all sums required to be
paid by Tenant to Landlord pursuant to the terms of this Lease.

         14. Destruction.

                  A. Landlord's Duty to Restore. If the Improvements are damaged
by any peril after the Commencement Date of this Lease, Landlord shall restore
the Premises unless the Lease is terminated by Landlord pursuant to Paragraph
14.B or by Tenant pursuant to Paragraph 14.C. All insurance proceeds available
from the property damage insurance carried by Landlord pursuant to Paragraph 8.C
shall be paid to and become the property of Landlord. If this Lease is
terminated pursuant to either Paragraphs 14.B or 14.C, then all insurance
proceeds available from the insurance required to be carried by Tenant which
covers loss to property that is Landlord's property or would become Landlord's
property on the termination of this Lease shall be paid to and become the
property of Landlord. If this Lease is not so terminated, then upon receipt of
the insurance proceeds (if the loss is covered by insurance) and the issuance of
all necessary governmental permits, Landlord shall commence and diligently
prosecute to completion the restoration of the Premises, to the extent then
allowed by Law, to substantially the same condition in which the Premises were
immediately prior to such damage. Landlord's obligation to restore shall be
limited to the Building and Tenant Improvements constructed by Landlord as they
existed as of the Commencement Date and any Tenant Improvements constructed by
Tenant for which Landlord receives

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insurance proceeds, excluding any trade fixtures and/or personal property
constructed or installed by Tenant in the Premises and excluding any alterations
constructed or installed by Tenant for which Landlord receives no insurance
proceeds. Unless this Lease is terminated, Tenant shall forthwith replace or
fully repair all trade fixtures installed by Tenant and existing at the time of
such damage or destruction.

                  B. Landlord's Right to Terminate. Landlord shall have the
option to terminate this Lease in the event any of the following occurs, which
option may be exercised only by delivery to Tenant of a written notice of
election to terminate within thirty (30) days after the date of such damage:

                            (1) The Improvements are damaged by any peril both
(i) not covered by the type of insurance Landlord is required to carry pursuant
to Paragraph 8.C, and (ii) not covered by valid and collectible insurance
actually carried by Landlord and in force at the time of such damage or
destruction.

                            (2) The Improvements are damaged by any peril during
the last twelve (12) months of the Lease Term to such an extent that the
estimated cost to restore equals or exceeds an amount equal to six (6) times the
Monthly Installment of rent then due; provided, however, that Landlord may not
terminate this Lease pursuant to this subparagraph if Tenant, at the time of
such damage, has an express written option to further extend the term of this
Lease and Tenant exercises such option to so further extend the Lease Term
within fifteen (15) days following the date of such damage.

                            (3) The Improvements are damaged by any peril and,
because of the Laws then in force, (i) may not be restored at reasonable costs
to substantially the same condition in which it was prior to such damage, or
(ii) if restored, may not be used for the same use being made thereof before
such damage.

                  C. Tenant's Right to Terminate. If the Improvements are
damaged by any peril and Landlord does not elect to terminate this Lease or is
not entitled to terminate this Lease pursuant to Paragraph 14.B, then as soon as
reasonably practicable, Landlord shall furnish Tenant with the written opinion
of Landlord's architect or construction consultant as to when the restoration
work required of Tenant may be completed. Tenant shall have the option to
terminate this Lease in the event any of the following occurs, which option may
be exercised only by delivery to Landlord of a written notice of election to
terminate within fifteen (15) days after Tenant receives from Landlord the
estimate of the time needed to complete such restoration:

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                            (1) The Improvements are damaged by any peril and,
in the reasonable opinion of Landlord's architect or construction consultant,
the restoration of the Premises cannot be substantially completed within two
hundred seventy (270) days after the issuance of necessary building permits for
such restoration.

                            (2) The Improvements are damaged by any peril within
twelve (12) months of the last day of the Lease Term, and, in the reasonable
opinion of Landlord's architect or construction consultant, the restoration of
the Premises cannot be substantially completed within ninety (90) days after the
date of such damage.

                  D. Abatement of Rent. In the event of damage to the Premises
which does not result in the termination of this Lease, the Monthly Installment
of rent and Additional Rent shall be temporarily abated during the period of
restoration in proportion to the degree to which Tenant's use of the Premises is
impaired by such damage. Tenant shall not be entitled to any compensation from
Landlord for loss of Tenant's property or loss to Tenant's business caused by 
such damage or restoration. Tenant hereby waives the provisions of Section 
1932, Subdivision 2, and Section 1933, Subdivision 4, of the California Civil
Code, and the provisions of any similar law, hereinafter enacted.

         15. Condemnation.

                  A. Definition of Terms. For the purposes of this Lease, the
term (1) "Taking" means a taking of the Premises or damage to the Premises
related to the exercise of the power of eminent domain and includes a voluntary
conveyance, in lieu of court proceedings, to any agency, authority, public
utility, person or corporate entity empowered to condemn property; (2) "Total
Taking" means the taking of the entire Premises or so much of the Premises as to
prevent or substantially impair the use thereof by Tenant for the uses herein
specified; (3) "Partial Taking" means a Taking which does not constitute a Total
Taking; (4) "Date of Taking" means the date upon which the title to the
Premises, or a portion thereof, passes to and vests in the condemnor or the
effective date of any order for possession if issued prior to the date title
vests in the condemnor; and (5) "Award" means the amount of any award made,
consideration paid, or damages ordered as a result of a Taking.

                  B. Rights. The parties agree that in the event of a Taking all
rights between them or in and to an Award shall be as set forth herein and
Tenant shall have no right to any Award except as set forth herein.

                  C. Total Taking. In the event of a Total Taking during the
term hereof (1) the rights of Tenant under the Lease and the leasehold estate of
Tenant in and to the Premises shall cease and

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terminate as of the Date of Taking; (2) Landlord shall refund to Tenant any
prepaid rent and any unapplied security deposit; (3) Tenant shall pay Landlord
any rent or charges due Landlord under the Lease, each prorated as of the Date
of Taking; (4) Tenant shall receive from the Award those portions of the Award
attributable to trade fixtures of Tenant (including Tenant's Property as defined
in Paragraph 32), moving expenses of Tenant; and (5) the remainder of the Award
shall be paid to and be the property of Landlord.

                  D. Partial Taking. In the event of a Partial Taking during the
term hereof (1) the rights of Tenant under the Lease and the leasehold estate of
Tenant in and to the portion of the Premises taken shall cease and terminate as
of the Date of Taking; (2) from and after the Date of Taking the Monthly
Installment of rent shall be reduced to an amount that bears the same
relationship to such Monthly Installment of rent before such reduction as the
fair market rental value of the Premises which remains after the Taking bears to
the fair market rental value of the Premises prior to the Taking; (3) Tenant
shall receive from the Award the portions of the Award attributable to trade
fixtures of Tenant (including Tenant's Property); and (4) the remainder of the
Award shall be paid to and be the property of Landlord.

         16. Mechanics' Lien. Tenant shall (A) pay for all labor and services
performed for, materials used by or furnished to, Tenant or any contractor
employed by Tenant with respect to the Premises; (B) indemnify, defend, protect
and hold Landlord and the Premises harmless and free from any liens, claims,
liabilities, demands, encumbrances, or judgments created or suffered by reason
of any labor or services performed for, materials used by or furnished to,
Tenant or any contractor employed by Tenant with respect to the Premises; (C)
give notice to Landlord in writing five (5) days prior to employing any laborer
or contractor to perform services related to, or receiving materials for use
upon the Premises; and (D) permit Landlord to post a notice of nonresponsibility
in accordance with the statutory requirements of California Civil Code Section
3094 or any amendment thereof. In the event Tenant is required to post an
improvement bond with a public agency in connection with the above, Tenant
agrees to include Landlord as an additional obligee.

         17. Inspection of the Premises. Tenant shall permit Landlord and its
agents to enter the Premises at any reasonable time for the purpose of
inspecting the same, performing Landlord's maintenance and repair
responsibilities (upon 24 hour prior notice except in an emergency) posting a
notice of non-responsibility for alterations, additions or repairs and at any
time within three hundred sixty-five (365) days prior to expiration of this
Lease, to place upon the Premises, ordinary "For Lease" or "For Sale" signs;
provided, however, (i) Landlord shall provide Tenant with prior notice of such
entry, (ii) Landlord may only enter the Premises in the

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company of an escort provided by Tenant if Tenant provides such escort on a
reasonable basis; (iii) Landlord shall use reasonable efforts to minimize any
interference with Tenant's business operations; and (iv) unless Tenant is in
default, Landlord may not place "For Lease" signs or show the Premises for lease
until the last one hundred eighty (180) days of the Lease Term.

         18. Compliance with Laws. Tenant shall, at its own cost, comply with
all of the requirements of all municipal, county, state and federal authorities
now in force, or which may hereafter be in force, pertaining to Tenant's use and
occupancy of the Premises, and shall faithfully observe all municipal, county,
state and federal law, statutes or ordinances now in force or which may
hereafter be in force pertaining to the use and occupancy of the Premises. 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 and
occupancy of the Premises shall be conclusive of the fact that such violation by
Tenant has occurred. Tenant shall indemnify, protect, defend, and hold Landlord
harmless against any loss, expense, damage, attorneys' fees or liability arising
out of the failure of Tenant to comply with any applicable law.

         19. Subordination. The following provisions shall govern the
relationship of this Lease to any underlying lease, mortgage or deed of trust
which now or hereafter affects the Premises or Landlord's interest or estate
therein and any renewal, modification, consolidation, replacement, or extension
thereof (a "Security Instrument").

                  A. Priority. This Lease is subject and subordinate to all
Security Instruments existing as of the Commencement Date. However, if any
Lender so requires, this Lease shall become prior and superior to any such
Security Instrument.

                  B. Subsequent Security Instruments. At Landlord's election,
this Lease shall become subject and subordinate to any Security Instrument
created after the Commencement Date provided that the Lender holding such
Security Agreement agrees that in the event of foreclosure of the Security
Instrument in question, such Lender shall recognize the tenancy of Tenant on the
terms and conditions contained in this Lease so long as Tenant is not in default
under this Lease. Notwithstanding such subordination, Tenant's right to quiet
possession of the Premises shall not be disturbed so long as Tenant is not in
default and performs all of its obligations under this Lease, unless this Lease
is otherwise terminated pursuant to its terms.

                  C. Documents. Tenant shall execute any reasonable document or
instrument required by Landlord or any Lender to make

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this Lease either prior or subordinate to a Security Instrument, which may
include such other matters as the Lender customarily requires in connection with
such agreements, including provisions that the Lender not be liable for (1) the
return of the Security Deposit unless the Lender receives it from Landlord, and
(2) any defaults on the part of Landlord occurring prior to the time that the
Lender takes possession of the Premises in connection with the enforcement of
its Security Instrument. Tenant's failure to execute any such document or
instrument within ten (10) days after written demand therefor shall constitute a
default by Tenant. Tenant's obligation to execute and deliver any subordination
agreement to any future Lender shall be conditioned upon such Lender agreeing
that in the event of foreclosure of the mortgage or termination of the ground
lease in question, such Lender shall recognize the tenancy of Tenant on the
terms and conditions contained in this Lease so long as Tenant is not in default
under this Lease.

                  D. Tenant's Attornment. Tenant shall attorn (1) to any
purchaser of the Premises at any foreclosure sale or private sale conducted
pursuant to any Security Instrument encumbering the Premises; (2) to any grantee
or transferee designated in any deed given in lieu of foreclosure; or (3) to the
Landlord under any underlying ground lease should such ground lease be
terminated.

         20. Holding Over. This Lease shall terminate without further notice at
the expiration of the Lease Term. Any holding over by Tenant after expiration
shall not constitute a renewal or extension or give Tenant any rights in or to
the Premises except as expressly provided in this Lease. Any holding over after
the expiration without the consent of Landlord shall be construed to be a
tenancy from month to month, at one hundred fifty percent (150%) of the monthly
rent for the last month of the Lease Term, and shall otherwise be on the terms
and conditions herein specified insofar as applicable.

         21. Notices. Any notice required or desired to be given under this
Lease shall be in writing with copies directed as indicated below and shall be
personally served or given by mail. Any notice given by mail shall be deemed to
have been given when seventy-two (72) hours have elapsed from the time such
notice was deposited in the United States mails, certified and postage prepaid,
return receipt requested, addressed to the party to be served with a copy as
indicated herein at the last address given by that party to the other party
under the provisions of this paragraph. At the date of execution of this Lease,

         the address of Landlord is:

                            2680 N. First Street, #280
                            San Jose, CA 95134

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         the address of Tenant is:

                            850 Maude Avenue
                            Mountain View, CA 94043

         22. Attorneys' Fees. In the event either party shall bring any action
or legal proceeding for damages for any alleged breach of any provision of this
Lease, to recover rent or possession of the Premises, to terminate this Lease,
or to enforce, protect or establish any term or covenant of this Lease or right
or remedy of either party, the prevailing party shall be entitled to recover as
a part of such action or proceeding, reasonable attorneys' fees and court costs,
including attorneys, fees and costs for appeal, as may be fixed by the court or
jury. The term "prevailing party" shall mean the party who received
substantially the relief requested, whether by settlement, dismissal, summary
judgment, judgment, or otherwise.

         23. Subleasing and Assignment.

                  A. Landlord's Consent Required. Tenant's interest in this
Lease is not assignable, by operation of law or otherwise, nor shall Tenant have
the right to sublet the Premises, transfer any interest of Tenant therein or
permit any use of the Premises by another party, without the prior written
consent of Landlord to each such assignment, subletting, transfer or use, which
consent Landlord agrees not to withhold unreasonably subject to the provisions
of Subparagraph 23.C below. A consent to one assignment, subletting, occupancy
or use by another party shall not be deemed to be a consent to any subsequent
assignment, subletting, occupancy or use by another party. Any assignment or
subletting without such consent shall be void and shall, at the option of
Landlord, terminate this Lease.

         Landlord's waiver or consent to any assignment or subletting hereunder
shall not relieve Tenant from any obligation under this Lease unless the consent
shall so provide.

                  B. Transferee Information Required. If Tenant desires to
assign its interest in this Lease or sublet the Premises, or transfer any
interest of Tenant therein, or permit the use of the Premises by another party
(hereinafter collectively referred to as a "Transfer"), Tenant shall give
Landlord at least fifteen (15) business days prior written notice of the
proposed Transfer and of the terms of such proposed Transfer, including, but not
limited to, the name and legal composition of the proposed transferee, a
financial statement of the proposed transferee, the nature of the proposed
transferee's business to be carried on in the Premises (including a list of the
type and quantities of all Hazardous Materials to be used by the transferee on
the Premises), the payment to be made or other consideration to be given to
Tenant on

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account of the Transfer, and such other pertinent information as may be
requested by Landlord, all in sufficient detail to enable Landlord to evaluate
the proposed Transfer and the prospective transferee.

                  C. Landlord's Rights. It is the intent of the parties hereto
that this Lease shall confer upon Tenant only the right to use and occupy the
Premises, and to exercise such other rights as are conferred upon Tenant by this
Lease. The parties agree that this Lease is not intended to have a bonus value
nor to serve as a vehicle whereby Tenant may profit by a future Transfer of this
Lease or the right to use or occupy the Premises as a result of any favorable
terms contained herein, or future changes in the market for leased space. It is
the intent of the parties that any such bonus value that may attach to this
Lease shall be and remain the exclusive property of Landlord, except as provided
in Paragraph 23.C(2) below. In the event Tenant seeks to Transfer its interest
in this Lease or the Premises, Landlord shall have the following options, which
may be exercised at its sole choice without limiting Landlord in the exercise of
any other right or remedy which Landlord may have by reason of such proposed
Transfer:

                            (1) In the event of a Transfer constituting either
an assignment of the entire Lease or a sublease of substantially all of the
Premises for the balance of the Lease Term, Landlord may elect to terminate this
Lease effective as of the proposed effective date of the proposed Transfer and
release Tenant from any further liability hereunder accruing after such
termination date by giving Tenant written notice of such termination within
fifteen (15) business days after receipt by Landlord of Tenant's notice of
intent to Transfer as provided above. If Landlord makes such election to
terminate this Lease, Tenant shall surrender the Premises, in accordance with
Paragraph 32, on or before the effective termination date; or

                            (2) Landlord may consent to the proposed Transfer on
the condition that Tenant agrees to pay to Landlord, as additional rent, fifty
percent (50%) of any and all rents or other consideration (including key money)
received by Tenant from the transferee by reason of such Transfer in excess of
the rent payable by Tenant to Landlord under this Lease (less any brokerage
commissions, attorneys' fees and advertising expenses incurred by Tenant in
connection with the Transfer). Tenant expressly agrees that the foregoing is a
reasonable condition for obtaining Landlord's consent to any Transfer; or

                            (3) Landlord may reasonably withhold its consent to
the proposed Transfer.

                  D. Permitted Transfers. Notwithstanding the foregoing, Tenant
may, without Landlord's prior written consent, assign its

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interest in the Lease or sublet the Premises or a portion thereof to (i) a
subsidiary, affiliate, division or corporation which controls or is controlled
by 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 the Tenant's assets;
provided that, in each instance described above, (a) the transferee (other than
in the case of a sublease) assumes the obligations of the Tenant under this
Lease in a written instrument delivered to Landlord; (b) the transferor tenant
remains liable as a primary obligor for the obligations of Tenant under this
Lease; and (c) the tangible net worth (determined in accordance with generally
accepted accounting principles) of the transferee tenant is no less than
Tenant's tangible net worth immediately prior to the date of such Transfer.

         24. Successors. The covenants and agreements contained in this Lease
shall be binding on the parties hereto and on their respective heirs,
successors and assigns (to the extent the Lease is assignable).

         25. Mortgagee Protection. In the event of any default on the part of
Landlord, Tenant will give notice by registered or certified mail to any
beneficiary of a deed of trust or mortgagee of a mortgage encumbering the
Premises, whose address shall have been previously furnished to Tenant. So long
as such beneficiary or mortgagee is making reasonable efforts to cure the
default, including, but not limited to, obtaining possession of the Premises by
power of sale or judicial foreclosure, if such should prove necessary to effect
a cure, Tenant shall not have the right to terminate this Lease.

         26. Estoppel Certificate. Tenant agrees within ten (10) days following
request by Landlord to (A) execute and deliver to Landlord any estoppel
certificates presented to Tenant by Landlord, (1) certifying that this Lease is
unmodified and in full force and effect and the date to which the rent and
other charges are paid in advance, if any, and (2) acknowledging that there are
not, to Tenant's knowledge, any uncured defaults on the part of Landlord
hereunder, or specifying the defaults, if any, and (3) evidencing the status of
the Lease as may be required either by a Lender making a loan to Landlord to be
secured by a deed of trust or mortgage covering the Premises or a purchaser of
the Premises from Landlord and (B) to deliver to Landlord the financial
statement of Tenant with an opinion of a certified public accountant, including
a balance sheet and profit and loss statement, for the last completed fiscal
year all prepared in accordance with generally accepted accounting principles
consistently applied; provided, however, if Tenant is a public company, Tenant
shall only be obligated to provide Landlord with the most recently issued
financial statements filed with the SEC as part of a 10-Q or 10-K.

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   23

Tenant's failure to deliver an estoppel certificate within ten (10) days
following such request shall be an Event of Default under this Lease.

         27. Surrender of Lease Not Merger. The voluntary or other surrender of
this Lease by Tenant, or a mutual cancellation thereof, shall not work a merger
and shall, at the option of Landlord, terminate all or any existing subleases or
subtenants, or operate as an assignment to Landlord of any or all such subleases
or subtenants.

         28. Waiver. The waiver by Landlord or Tenant of any breach of any term,
covenant or condition herein contained shall not be deemed to be a waiver of
such term, covenant or condition or any subsequent breach of the same or any
other term, covenant or condition herein contained. Any waiver shall be in
writing and signed by both Landlord and Tenant.

         29. General.

                  A. Captions. The captions and paragraph headings used in this
Lease are for the purposes of convenience only. They shall not be construed to
limit or extend the meaning of any part of this Lease, or be used to interpret
specific sections. The word(s) enclosed in quotation marks shall be construed
as defined terms for purposes of this Lease. As used in this Lease, the
masculine, feminine and neuter and the singular or plural number shall each be
deemed to include the other whenever the context so requires.

                  B. Definition of Landlord. The term Landlord as used in this
Lease, so far as the covenants or obligations on the part of Landlord are
concerned, shall be limited to mean and include only the owner at the time in
question of the fee title of the Premises, and in the event of any transfer or
transfers of the title of such fee, the Landlord herein named (and in case of
any subsequent transfers or conveyances, the then grantor) shall be
automatically freed and relieved of all liability with respect to performance of
any covenants or obligations on the part of Landlord contained in this Lease to
be performed after the date of such transfer or conveyance; provided that (i) 
any funds in the hands of Landlord or the then grantor at the time of such 
transfer, in which Tenant has an interest, shall be turned over to the grantee, 
and (ii) the grantee assumes the obligations on the part of Landlord contained 
in this Lease to be performed after the date of such transfer or conveyance. 
It is intended that the covenants and obligations contained in this Lease on 
the part of Landlord shall, subject as aforesaid, be binding upon each 
Landlord, its heirs, personal representatives, successors and assigns only 
during its respective period of ownership.



                                       23
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                  C. Time of Essence. Time is of the essence for the performance
of each term, covenant and condition of this Lease.

                  D. Severability. In case any one or more of the provisions
contained herein, except for the payment of rent, shall for any reason be held
to be invalid, illegal or unenforceable in any respect, such invalidity,
illegality or unenforceability shall not affect any other provision of this
Lease, but this Lease shall be construed as if such invalid, illegal or
unenforceable provision had not been contained herein. This Lease shall be
construed and enforced in accordance with the laws of the State of California.

                  E. Quiet Enjoyment. Upon Tenant paying the rent for the
Premises and observing and performing all of the covenants, conditions and
provisions on Tenant's part to be observed and performed hereunder, Tenant shall
have quiet possession of the Premises for the entire term hereof subject to all
of the provisions of this Lease.

                  F. Law. As used in this Lease, the term "Law" or "Laws" shall
mean any judicial decision, statute, constitution, ordinance, resolution,
regulation, rule, administrative order, or other requirement of any government
agency or authority having jurisdiction over the parties to this Lease or the
Premises or both, in effect at the Commencement Date of this Lease or any time
during the Lease Term, including, without limitation, any regulation, order, or
policy of any quasi-official entity or body (e.g., board of fire examiners,
public utility or special district).

                  G. Agent . As used in this Lease, the term "Agent" shall
mean, with respect to either Landlord or Tenant, its respective agents,
employees, contractors (and their subcontractors), and invitees (and in the case
of Tenant, its subtenants).

                  H. Lender. As used in this Lease, the term "Lender" shall mean
any beneficiary, mortgagee, secured party or other holder of any deed of trust,
mortgage or other written security device or agreement affecting Landlord's
interest in the Premises.

         30. Sign. Tenant shall not place or permit to be placed any sign or
decoration on the Parcel or the exterior of the Building without the prior
written consent of Landlord and the city of Mountain View. Tenant, upon written
notice by Landlord, shall immediately remove any sign or decoration that Tenant
has placed or permitted to be placed on the Parcel or the exterior of the
Building without the prior written consent of Landlord, and if Tenant fails to
so remove such sign or decoration within five (5) days after Landlord's written
notice, Landlord may enter upon the Premises and remove said sign or decoration
and Tenant agrees to

                                       24
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pay Landlord, as additional rent upon demand, the cost of such removal. At the
termination of this Lease, Tenant shall remove any sign which it has placed on
the Parcel or Building and shall repair any damage caused by the installation or
removal of such sign.

         31. Interest on Past Due Obligations. Any Monthly Installment of rent
due from Tenant, or any other sum due under this Lease from Tenant, which is
received by Landlord after the date ten (10) days following the date written
notice is given by Landlord to Tenant that such sum has not been paid when due,
shall bear interest from said due date until paid, at an annual rate equal to
the lower of (the "Permitted Rate"): (1) twelve percent (12%) ; or (2) five
percent (5%) plus the rate established by the Federal Reserve Bank of San
Francisco, as of the twenty-fifth (25th) day of the month immediately preceding
the due date, on advances to member banks under Sections 13 and 13(a) of the
Federal Reserve Act, as now in effect or hereafter from time to time amended.
Payment of such interest shall not excuse or cure any default by Tenant. In
addition, Tenant shall pay all costs and attorneys' fees incurred by Landlord in
collection of such amounts.

         32. Surrender of the Premises. On the last day of the term hereof, or
on the sooner termination of this Lease, Tenant shall surrender the Premises to
Landlord in their condition existing as of the Commencement Date of this Lease,
ordinary wear and tear excepted, with all originally painted interior walls
washed, and other interior walls cleaned, and repaired or replaced, the air
conditioning and heating equipment serviced and repaired by a reputable and
licensed service firm, all floors cleaned and waxed, all to the reasonable
satisfaction of Landlord. All improvements made by Tenant to the Premises, other
than fume hoods, benches, shelving, environmental rooms and equipment (the
"Tenant's Property"), shall be the property of Landlord and shall remain on
the Premises at termination of the Lease. Tenant shall remove all of Tenant's
personal property and trade fixtures (including fume hoods, benches, shelving,
environmental rooms and equipment) from the Premises, and all property not so
removed shall be deemed abandoned by Tenant. Tenant, at its sole cost, shall
repair any damage to the Premises caused by the removal of Tenant's personal
property, machinery and equipment, which repair shall include, without
limitation, the patching and filling of holes and repair of structural damage.
If the Premises are not so surrendered at the termination of this Lease, Tenant
shall indemnify, defend, protect and hold Landlord harmless from and against
loss or liability resulting from delay by Tenant in so surrendering the Premises
including without limitation, any claims made by any succeeding tenant or losses
to Landlord due to lost opportunities to lease to succeeding tenants.




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         33. Authority. The undersigned parties hereby warrant that they have
proper authority and are empowered to execute this Lease on behalf of Landlord
and Tenant, respectively.

         34. C. C. &: R.'s. This Lease is made subject to all matters of public
record affecting title to the property of which the Premises are a part. Tenant
shall abide by and comply with all private conditions, covenants and
restrictions of public record now or hereafter affecting the Premises and any
amendment thereof (the "CC&R's).

        All assessments and charges which are imposed, levied or assessed
against the Premises pursuant to the above-described covenants, conditions and
restrictions shall be paid by Tenant as Additional Rent.

         35. Brokers. The brokers involved in this transaction are KG Real
Estate, Inc. as "listing broker" and Cornish and Carey Commercial as
"cooperating broker". A "cooperating broker" is defined as any broker other than
the listing broker entitled to a share of any commission arising under this
Lease. Upon execution of this Lease by both parties, Landlord shall pay to said
brokers jointly, or in such separate shares as they may mutually designate in
writing, a fee as set forth in a separate agreement between Landlord and listing
broker.

         36. Limitation on Landlord's Liability. Tenant, for itself and its
successors and assigns (to the extent this Lease is assignable) , hereby agrees
that in the event of any actual, or alleged, breach or default by Landlord under
this Lease that:

                  A. Tenant's sole and exclusive remedy and recourse against
Landlord shall be as against Landlord's interest in the Premises;

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

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

                  D. No partner of Landlord shall be required to answer or
otherwise plead to any service of process;

                  E. No judgment will be taken against any partner of Landlord;

                  F. Any judgment taken against any partner of Landlord may be
vacated and set aside at any time nunc pro tunc;

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                  G. No writ of execution will ever be levied against the assets
of any partner of Landlord; and

                  H. The covenants and agreements of Tenant set forth in this
Paragraph 36 shall be enforceable by Landlord and any partner of Landlord.

         37. Hazardous Material.

                  A. Definitions. As used herein, the term "Hazardous Material"
shall mean any substance: (i) the presence of which requires investigation or
remediation under any federal, state or local statute, regulation, ordinance,
order, action, policy or common law; (ii) which is or becomes defined as a
"hazardous waste," "hazardous substance," pollutant or contaminant under any
federal, state or local statute, regulation, rule or ordinance or amendments
thereto including, without limitation, the Comprehensive Environmental Response,
Compensation and Liability Act (42 U.S.C. Section 9601 et seq.) and/or the
Resource Conservation and Recovery Act (42 U.S.C. Section 6901 et seq.) ; (iii)
which is toxic, explosive, corrosive, flammable, infectious, radioactive,
carcinogenic, mutagenic, or otherwise hazardous and is or becomes regulated by
any governmental authority, agency, department, commission, board, agency or
instrumentality of the United States, the State of California or any political
subdivision thereof; (iv) the presence of which on the Premises causes or
threatens to cause a nuisance upon the Premises or to adjacent properties or
poses or threatens to pose a hazard to the health or safety of persons on or
about the Premises; (v) the presence of which on adjacent properties could
constitute a trespass by Landlord or Tenant; (vi) without limitation which
contains gasoline, diesel fuel or other petroleum hydrocarbons; (vii) without
limitation which contains polychlorinated biphenyls (PCBs), asbestos or urea
formaldehyde foam insulation; or (viii) without limitation radon gas.

                  B. Permitted Use. Subject to the compliance by Tenant with the
provisions of Subparagraphs C, D, E, F, G, I, and J below, Tenant shall be
permitted to use and store on the Premises those Hazardous Materials listed in
EXHIBIT "D" attached hereto, in the quantities set forth in EXHIBIT "D" and any
other Hazardous Materials reasonably required for Tenant's business provided
that Tenant provides Landlord with quarterly reports of the use and storage of
such Hazardous Materials and such use and storage are approved by Landlord.

                  C. Hazardous Materials Management Plan. (i) Prior to Tenant
using, handling, transporting or storing any Hazardous Material at or about the
Premises (including, without limitation, those listed in EXHIBIT "D" ), Tenant
shall submit to Landlord a Hazardous Materials Management

                                       27
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Plan ("HMMP") for Landlord's review and approval, which approval shall not be
unreasonably withheld. The HMMP shall describe: (aa) the quantities of each
material to be used, (bb) the purpose for which each material is to be used,
(cc) the method of storage of each material, (dd) the method of transporting
each material to and from the Premises and within the Premises, (ee) the methods
Tenant will employ to monitor the use of the material and to detect any leaks or
potential hazards, and (ff) any other information any department of any
governmental entity (city, state or federal) requires prior to the issuance of
any required permit for the Premises or during Tenant's occupancy of the
Premises. Landlord may, but shall have no obligation to review and approve the
foregoing information and HMMP, and such review and approval or failure to
review and approve shall not act as an estoppel or otherwise waive Landlord's
rights under this Lease or relieve Tenant of its obligations under this Lease.
If Landlord determines in good faith by inspection of the Premises or review of
the HMMP that the methods in use or described by Tenant are not adequate in
Landlord's good faith judgment to prevent or eliminate the existence of
environmental hazards, then Tenant shall not use, handle, transport, or store
such Hazardous Materials at or about the Premises unless and until such methods
are approved by Landlord in good faith and added to an approved HMMP. Once
approved by Landlord, Tenant shall strictly comply with the HMMP and shall not
materially change its use, operations or procedures with respect to Hazardous
Materials without submitting an amended HMMP for Landlord's review and approval
as provided above.

                            (ii) Tenant shall pay to Landlord when Tenant
submits an HMMP (or amended HMMP) the amount reasonably determined by Landlord
to cover all Landlord's costs and expenses reasonably incurred in connection
with Landlord, s review of the HMMP which costs and expenses shall include,
among other things, all reasonable out-of-pocket fees of attorneys, architects,
or other consultants incurred by Landlord in connection with Landlord's review
of the HMMP. Landlord shall have no obligation to consider a request for consent
to a proposed HMMP unless and until Tenant has paid all such costs and expenses
to Landlord, and Tenant shall pay all such costs and expenses to Landlord
irrespective of whether Landlord consents to such proposed HMMP. Tenant shall
pay to Landlord on demand the excess, if any, of such costs and expenses
actually incurred by Landlord over the amount of such costs and expenses
actually paid by Tenant, and Landlord shall promptly refund to Tenant the
excess, if any, of such costs and expenses actually paid by Tenant over the
amount of such costs and expenses actually incurred by Landlord.

                  D. Use Restriction. Except as specifically allowed in
Subparagraph C above, Tenant shall not cause or permit any Hazardous Material to
be used, stored, generated, discharged, transported to or from, or disposed of
in or about the Premises, or

                                       28
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any other land or improvements in the vicinity of the Premises. Without limiting
the generality of the foregoing, Tenant, at its sole cost, shall comply with all
Laws relating to the storage, use, generation, transport, discharge and disposal
by Tenant or its Agents of any Hazardous Material. If the presence of any
Hazardous Material on the Premises caused or permitted by Tenant or its Agents
results in contamination of the Premises or any soil, air, ground or surface
waters under, through, over, on, in or about the Premises, Tenant, at its
expense, shall promptly take all actions necessary to return the Premises and/or
the surrounding real property to the condition existing prior to the appearance
of such Hazardous Material. In the event there is a release, discharge or
disposal of or contamination of the Premises by a Hazardous Material which is of
the type that has been stored, handled, transported or otherwise used or
permitted by Tenant or its Agents on or about the Premises, Tenant shall have
the burden of proving that such release, discharge, disposal or contamination is
not the result of the acts or omissions of Tenant or its Agents.

                  E. Tenant Indemnity. Tenant shall defend, protect, hold
harmless and indemnify Landlord and its Agents and Lenders with respect to all
actions, claims, losses (including, diminution in value of the Premises), fines,
penalties, fees (including, but not limited to, attorneys, and consultants'
fees) costs, damages, liabilities, remediation costs, investigation costs,
response costs and other expenses arising out of, resulting from, or caused by 
(i) any Hazardous Material used, generated, discharged, transported to or from,
stored, or disposed of by Tenant or its Agents in, on, under, over, through or
about the Premises and/or the surrounding real property or (ii) any disposal or
release of any Hazardous Material on the surface of the Premises occurring after
the Commencement Date and prior to the termination of this Lease that is not the
result of the negligent acts or willful misconduct of Landlord or its Agents.
Tenant shall not suffer any lien to be recorded against the Premises as a
consequence of the disposal of any Hazardous Material on the Premises by Tenant
or its Agents, including any so called state, federal or local "super fund" lien
related to the "clean up" of any Hazardous Material in, over, on, under,
through, or about the Premises.

                  F. Compliance. Tenant shall immediately notify Landlord of any
inquiry, test, investigation, enforcement proceeding by or against Tenant or the
Premises of which Tenant has knowledge concerning any Hazardous Material. Any
remediation plan prepared by or on behalf of Tenant must be submitted to
Landlord prior to conducting any work pursuant to such plan and prior to
submittal to any applicable government authority and shall be subject to
Landlord's consent. Tenant acknowledges that Landlord, as the owner of the
Property, at its election, shall have the sole right to negotiate, defend,
approve and appeal any action taken or


                                       29
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order issued with regard to any Hazardous Material by any applicable
governmental authority.

                  G. Assignment and Subletting. It shall not be unreasonable
for Landlord to withhold its consent to any proposed assignment or subletting if
(i) the proposed assignee's or subtenant's anticipated use of the Premises
involves the storage, generation, discharge, transport, use or disposal of any
Hazardous Material not approved by Landlord; (ii) if the proposed assignee or
subtenant has been required by any prior landlord, lender or governmental
authority to "clean up" or remediate any Hazardous Material; (iii) if the
proposed assignee or subtenant is subject to investigation or enforcement order
or proceeding by any governmental authority in connection with the use,
generation, discharge, transport, disposal or storage of any Hazardous Material;
provided that (ii) and (iii) shall not apply in the Lease of a Fortune 500
Company.

                  H. Surrender. Upon the expiration or earlier termination of
the Lease, Tenant, at its sole cost, shall remove all Hazardous Materials from
the Premises that Tenant or its Agents introduced to the Premises. If Tenant
fails to so surrender the Premises, Tenant shall indemnify, protect, defend and
hold Landlord harmless from and against all damages resulting from Tenant's
failure to surrender the Premises as required by this Paragraph, including,
without limitation, any actions, claims, losses, liabilities, fees (including,
but not limited to, attorneys' and consultants' fees), fines, costs, penalties,
or damages in connection with the condition of the Premises including, without
limitation, damages occasioned by the inability to relet the Premises or a
reduction in the fair market and/or rental value of the Premises by reason of
the existence of any Hazardous Material in, on, over, under, through or around
the Premises.

                  I. Right to Appoint Consultant. Landlord shall have the right
to appoint a consultant to conduct an investigation to determine whether any
Hazardous Material is being used, generated, discharged, transported to or from,
stored or disposed of in, on, over, through, or about the Premises, in an
appropriate and lawful manner. If Tenant has violated any Law or covenant in
this Lease regarding the use, storage or disposal of Hazardous Materials on or
about the Premises, Tenant shall reimburse Landlord for the cost of such
consultant and investigation. Tenant, at its expense, shall comply with all
reasonable recommendations of the consultant required to conform Tenant's use,
storage or disposal of Hazardous Materials to the requirements of applicable Law
or to fulfill the obligations of Tenant hereunder.

                  J. Holding Over. If any action of any kind is required or
requested to be taken by any governmental authority to clean-up, remove,
remediate or monitor any Hazardous Material (the presence

                                       30
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of which is the result of the acts or omissions of Tenant or its Agents) and
such action is not completed prior to the expiration or earlier termination of
the Lease, Tenant shall be deemed to have impermissibly held over until such
time as such required action is completed, and Landlord shall be entitled to all
damages directly or indirectly incurred in connection with such holding over,
including without limitation, damages occasioned by the inability to re-let the
Premises or a reduction of the fair market and/or rental value of the Premises.

                  K. Existing Environmental Reports. Tenant hereby acknowledges
that it has received, read and reviewed the reports and test results described
in EXHIBIT "E" attached hereto and made a part hereof (the "Existing
Environmental Reports"). The Hazardous Materials currently present in, on or
under the Premises as described in the Existing Environmental Reports are
referred to herein as the "Existing Environmental Condition"). Except as
disclosed in the Existing Environmental Reports, Landlord represents that it has
no knowledge of (i) the presence of any Hazardous Materials on the Premises or 
the soil surface, water or groundwater thereof, (ii) the presence of any 
underground storage tanks on the Premises, or (iii) any action, proceeding or 
claim pending or threatened with respect to any Hazardous Materials on or 
about the Premises. Landlord has in its possession no environmental report 
relating to the Premises other than the Existing Environmental Report.

                  L. Provisions Survive Termination. The provisions of this
Paragraph 37 shall survive the expiration or termination of this Lease.

                  M. Controlling Provisions. The provisions of this Paragraph
37 are intended to govern the rights and liabilities of the Landlord and Tenant
hereunder respecting Hazardous Materials to the exclusion of any other
provisions in this Lease that might otherwise be deemed applicable. The
provisions of this Paragraph 37 shall be controlling with respect to any
provisions in this Lease that are inconsistent with this Paragraph 37.

         38. Option to Extend.

                  A. Provided that Tenant is not in material default under this
Lease at the time of exercise of the hereinafter described option or at the time
of termination of then existing term of this Lease, as the case may be, Tenant
shall have one (1) option to extend the term of this Lease for a period of five
(5) years (the "Extended Term"). Tenant may exercise said option only by giving
Landlord written notice of its exercise of said option no later than one hundred
eighty (180) days prior to the expiration date of this Lease. If Tenant does not
notify Landlord in writing prior to the time frame as stipulated above, this
Option to Renew

                                       31
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shall be null and void. In all respects, the terms, covenants and conditions of
this Lease shall remain unchanged during the Extended Term, except that the
Monthly Installment of rent payable during the Extended Term shall be increased
in accordance with subparagraph B. below, and except that there shall be no
further Option to Extend the term of this Lease at the end of the Extended Term.

                  B. Promptly following the exercise of each option to extend,
the parties shall meet and endeavor to agree upon the Fair Market Rental
(including initial rental rate of the Extended Term and amount and timing of
increases during the Extended Term) of the Premises as of the first day of the
Extended Term. In determining the Fair Market Rental for the Premises, the
Premises shall be compared only to research and development buildings of a
similar quality and size and with similar improvements and amenities in Santa
Clara County and all legal uses of the Premises shall be considered. If within
thirty (30) days after the exercise of the option, the parties cannot agree upon
the Fair Market Rental for the Premises as of the first day of the Extended
Term, either party may terminate this Option by giving written notice to the
other party prior to the expiration of the thirty (30) day period. If neither
party elects to terminate the Option then both parties shall submit the matter
to binding appraisal in accordance with the following procedure: Within thirty
(30) days after the exercise of the Option, the parties shall either (a) jointly
appoint an appraiser for this purpose or (b) failing this joint action
separately designate a disinterested appraiser. No person shall be appointed or
designated an appraiser unless he or she has at least five (5) years experience
in appraising major commercial property in Santa Clara County and is a member of
a recognized society of real estate appraisers. If, within thirty five (35) days
after the appointment, the two appraisers reach agreement on the Fair Market
Rental for the Premises as of the first day of the Extended Term, that value
shall be binding and conclusive upon the parties. If the two appraisers thus
appointed cannot reach agreement on the question presented within thirty (30)
days after their appointment, then the appraisers thus appointed shall appoint a
third disinterested appraiser having like qualifications. If within thirty (30)
days after the appointment of the third appraiser, a majority of appraisers
agree on the Fair Market Rental of the Premises as of the first day of the
Extended Term, that value shall be binding and conclusive upon the parties. If
within thirty (30) days after the appointment of the third appraiser, a majority
of the appraisers cannot reach agreement on the question presented, then the
three appraisers shall each submit their independent appraisal to the parties
and the appraisal farthest from the median of the three appraisals shall be
disregarded and the mean average of the remaining two appraisals shall be deemed
to be the Fair Market Rental of the Premises as of the first day of the Extended
Term and shall be binding and conclusive upon the parties. Each

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party shall pay the fees and expenses of the appraiser appointed by it and shall
share equally the fees and expenses of the third appraiser. If the two
appraisers appointed by the parties cannot agree on the appointment of the third
appraiser, they or either of them shall give notice of such failure to agree to
the parties and if the parties fail to agree upon the selection of such third
appraiser within ten (10) days after the appraisers appointment by the parties
give such notice, then either of the parties, upon notice to the other party,
may request such appointment by the American Arbitration Association, or on its
failure, refusal or inability to act, may apply for such appointment to the
presiding judge of the Superior Court of Santa Clara County, California.

         IN WITNESS WHEREOF, the parties have executed this Agreement on the
dates set forth below.

LOGUE INVESTMENTS, L.P.,             MICROCIDE PHARMACEUTICALS, INC.,
a California limited partnership     a Delaware corporation


By: /s/  NAHUM GUZIK                 By: /s/  DR. KEITH BOSTIAN      
    ----------------------------         ---------------------------
    NAHUM GUZIK,                         DR. KEITH BOSTIAN, COO
   Managing Partner



DATED:         8/13/96               DATED:        8/1/96 
       -------------------------            ------------------------


                                       33
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                                  EXHIBIT "A"

                           Legal Description of Parcel

                                  [SITE PLAN]



                                       34
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                                   EXHIBIT "B"

                                    Site Plan

                                  [SITE PLAN]










                                       35
   36
                                  EXHIBIT "C"

                              IMPROVEMENT AGREEMENT

         1. Landlord Responsibilities. As soon as practicable after execution of
this Lease, Landlord shall construct the following certain interior improvements
in the Premises as shown in Exhibit "1":

                  (a) bring exterior of the building current with all building
codes only as required by the city.

                  (b) bring all HVAC, plumbing, electrical, and roof to good
operating condition upon commencement of Lease.

         Landlord is currently renovating the exterior of the Premises and will
be responsible to complete, per its plans, exterior landscaping around property,
install windows around Building, repaint exterior walls and slurry seal parking
lot including striping of parking spaces. If possible, Landlord will install a
fence on the adjacent parking lot along Logue Avenue which will block the view
of the parking lot of the building next door.

         No additional improvements to the Premises will be made by Landlord.

         2. Tenant Responsibilities. Tenant shall be responsible for all other
improvements, including ADA compliance, to the interior of the Premises. Any
improvements made shall be at Tenant's sole cost and expense, subject to
approval of Landlord per terms of Lease and Landlord shall have no
responsibility therefor.

         Tenant shall not make, or suffer to be made, any alterations,
improvements or additions in, on, about or to the Premises or any part thereof,
without the prior written consent of Landlord (which consent shall not be
unreasonably withheld) and without a valid building permit issued by the
appropriate governmental authority.



                                       36
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                                   EXHIBIT "D"

                           LIST OF HAZARDOUS MATERIALS
                         TENANT WILL USE ON THE PREMISES








                                       37
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                                   EXHIBIT "E"

                  DESCRIPTION OF EXISTING ENVIRONMENTAL REPORTS


         1. Level 1 Environmental Site Assessment For The Property Located at
320 Logue Avenue, Mountain View, California, June 23, 1993. Prepared by: Soil
Tech Engineering, Inc., 298 Brokaw Road, Santa Clara, California 95050.








                                       38
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Business Name:      Microcide Pharmaceuticals                      Date: 8/5/96
Facility Address:   85O Maude Avenue

                     ALPHABETICAL LIST OF CHEMICAL INVENTORY

2-Propanol
Acetic acid
Acetone
Acetone-Mol Div
Acetonitrile
Acrylamide
Agar/Media prep materials
Aluminum Oxide
Ammonium Acetate
Ammonium Chloride
Ammonium Hydroxide
Argon
Argon-zero grade
Associated Irritant Solids
Assorted Combustible Liquids
Assorted Corrosive Liquids
Assorted Corrosive Solids
Assorted Flammable Liquids
Assorted Flammable Solids
Assorted Irritant Liquids
Assorted Irritant Solids
Assorted Other Regulated Material Liquids
Assorted Other Regulated Material Solids
Assorted Other Regulated Materials
Assorted Other Regulated Materials Liquids
Assorted Other Regulated Materials Solids
Assorted Other Regulated Materials- Liquids
Assorted Other Regulated Materials- Solids
Assorted Other Regulated Materials-Solids
Assorted Oxidizer Liquids
Assorted Oxidizer Solids
Assorted Poison Liquids
Assorted Poison Solids
Assorted Poison Solids
Benzene
Benzophenone,
Boric Acid
Calcium Chloride
   40
Calcium Chloride Dihydrate
Calcium Hydroxide
Calcium Sulfate
Carbon-14
Celite
Chlorine
Chloroform
Copper powder
Copper Sulfate
Cupric Sulfate
Denatured Ethanol
Detergents
Dichloromethane
Diesel
Diethyl ether
Diethyl Sulfate
Dimethyl sulfoxide
Drierite
EDTA
Ethanol
Ethanol Denatured
Ethanol Undenatured
Ethanol, undenatured
Ethyl Acetate
Formaldehyde
Glycerol
Helium
Hexadecyl Trimethyl-Ammonium Bromide
Hexane
Hexanes
Hydrochloric Acid
Hydrogen
Hydrogen Chloride
Hydrogen-3
Iodine-125
Isopropanol
Lauryl sarcosine
Lauryl sulfate
Liquid Nitrogen
Lithium chloride
Magnesium chloride
Magnesium sulfate
Magnesium Sulfate Anhydrous
   41
Magnesium Turnings
Maleic acid
Manganese chloride
Manganese Sulfate
Methanol
Methylene Chloride
Molecular Sieves-4A
MOPS/3-Morpholineopropanesulfonic Acid
n-Butanol
Nitric Acid
Nitric Acid-Fuming
Nitrogen
Nitrogen gas
Nitrogen, liquid
Phosphoric Acid
Phosphorous-32
Polvinyl Pyrrolidone
Potassium Acetate
Potassium Bicarbonate
Potassium Carbonate
Potassium Chloride
Potassium Hydroxide
Potassium Hydroxide Pellets
Potassium Phosphate Dibasic
Potassium Phosphate Dibasic Powder
Potassium Phosphate Monobasic
Potassium Phosphate Monobasic Crystal
Quinolinol
Sand
Silica Gel (60-200mesh)
Silicon oil
Sodium Acetate
Sodium Bicarbonate
Sodium Carbonate
Sodium Carbonate Monohydrate Crystal
Sodium Chloride
Sodium Citrate
Sodium Dodecyl Sulfate
Sodium Hydroxide
Sodium Phosphate
Sodium Phosphate Dibasic
Sodium Phosphate Monobasic
Sodium Sulfate Anhydrous
   42
Sodium Sulfite
Sodium Thiosulfate,
Sulfur
Sulfur-35
Sulfuric Acid
Taurine
Tetrahydrofuran
Toluene
Trichloroacetic acid
Urea
White Light Mineral Oil
Zinc Sulfate