<PAGE>


                                                               EXHIBIT 10.21


<PAGE>

                             300 CONSTITUTION DRIVE
                                  OFFICE LEASE

                          TYCO ELECTRONICS CORPORATION

                                    Landlord

                                       and

                         INTERWAVE COMMUNICATIONS, INC.,

                                     Tenant


<PAGE>


                             300 CONSTITUTION DRIVE
                                  OFFICE LEASE
                             BASIC LEASE INFORMATION

<TABLE>

<S>                                                    <C>
Date:                                                  November 24, 1999

Landlord:                                              Tyco Electronics Corporation,
                                                       a Pennsylvania corporation

Tenant:                                                interWave Communications, Inc.,
                                                       a Delaware corporation

Building:                                              Building I
                                                       300 Constitution Drive
                                                       Menlo Park, California 94025

Premises:                                              Portion of first floor and entire second floor
                                                       as shown on Exhibit A

Area of Premises:                                      55,969 square feet

Scheduled Commencement Date:                           December 15, 1999

Lease Term:                                            Five (5) years, one and one-half (1 1/2)
                                                       months

Option to Extend:                                      Option to extend for five (5) years
                                                       (subject to Landlord's rights under
                                                       Section 18.2)

Initial Monthly Base Rent:                             $ 169,026.38

Advance Rental Payment:                                $ 169,026.38 as Base Rent for March 2000

Tenant's Share                                         See Sections 4.2 and 4.5

Base Tax Amount:                                       $ 0.11 per square foot, per month
                                                       $ 6,175.19 total, per month

Base Insurance Amount:                                 $ 0.01 per square foot, per month
                                                       $ 500.27 total, per month

                                       1
<PAGE>



Utility Allowance:                                     $ 0.17 per square foot, per month
                                                       $ 9,473.80 total, per month

Use:                                                   General office, engineering, engineering
                                                       labs, software and hardware development
                                                       and all other legally-permitted related
                                                       uses

Security, Deposit:                                     $676,100 Letter of Credit

Guarantor:                                             None

Tenant's Address prior to Occupancy                    656 Bair Island Road
of Premises                                            Redwood City, CA 94063

Tenant's Address for Notices                           interWave Communications, Inc.
                                                       300 Constitution Drive, Building I
                                                       Menlo Park, California 94025

Landlord's Address for Notices                         Attention: Property Manager
                                                       300 Constitution Drive, Building I
                                                       Menlo Park, California 94025

Landlord's Broker                                      Cornish & Carey Commercial

Tenant's Broker                                        Cornish & Carey Commercial

</TABLE>

The foregoing Basic Lease Information is hereby incorporated into and made a
part of this Lease. Each reference in this Lease to any of the terms set
forth above shall be deemed to include the respective information set forth
above opposite such term and shall also be construed to incorporate all of
the terms provided under the particular provision of this Lease pertaining to
such term and information. In the event of any conflict between any
provisions of the Basic Lease Information and provisions of this Lease, the
Lease shall prevail and control.

                                       2
<PAGE>


                             300 CONSTITUTION DRIVE
                                  OFFICE LEASE

<TABLE>
<CAPTION>
                                TABLE OF CONTENTS

                                                                                                                PAGE
<S>                                                                                                             <C>
ARTICLE 1 - PREMISES...............................................................................................1

         SECTION 1.1.           PREMISES...........................................................................1

         SECTION 1.2.           AREA OF PREMISES...................................................................1

         SECTION 1.3.           COMMON AREA........................................................................1

         SECTION 1.4.           CONDITION OF PREMISES..............................................................2

ARTICLE 2 - TERM AND POSSESSION ...................................................................................3

         SECTION 2.1.           TERM...............................................................................3

         SECTION 2.2.           IMPROVEMENTS.......................................................................4

ARTICLE 3 - RENT ..................................................................................................4

         SECTION 3.1.           BASE RENT..........................................................................4

         SECTION 3.2.           PAYMENT............................................................................4

         SECTION 3.3.           PARTIAL MONTHS.....................................................................4

ARTICLE 4 - TAX, INSURANCE ADJUSTMENT .............................................................................5

         SECTION 4.1.           EXCESS TAXES.......................................................................5

         SECTION 4.2.           TAXES..............................................................................5

         SECTION 4.3.           ADDITIONAL TAXES...................................................................6

         SECTION 4.4.           EXCESS INSURANCE COSTS.............................................................7

         SECTION 4.5.           INSURANCE COSTS....................................................................7

ARTICLE 5 - INTENTIONALLY OMITTED .................................................................................8

ARTICLE 6 - USE ...................................................................................................8

         SECTION 6.1.           GENERAL............................................................................8

                                       i
<PAGE>



                                TABLE OF CONTENTS
                                   (CONTINUED)
<CAPTION>
                                                                                                                PAGE
<S>                                                                                                             <C>
         SECTION 6.2.          NUISANCE OR WASTE...................................................................8

         SECTION 6.3.          COMPLIANCE WITH LAW.................................................................8

         SECTION 6.4.          HAZARDOUS MATERIALS.................................................................9

         SECTION 6.5.          EXISTING CONDITION.................................................................10

         SECTION 6.6.          RULES AND REGULATIONS..............................................................10

         SECTION 6.7.          COMMON AREA PROVISIONS.............................................................11

ARTICLE 7 - SERVICES AND UTILITIES................................................................................11

         SECTION 7.1.          GENERAL............................................................................11

         SECTION 7.2.          UTILITY SERVICES...................................................................13

         SECTION 7.3.          SUPPLEMENTARY SERVICES.............................................................13

         SECTION 7.4.          INTERRUPTION OF ACCESS, USE OR SERVICES............................................13

ARTICLE 8 - ALTERATIONS...........................................................................................14

         SECTION 8.1.          GENERAL............................................................................14

         SECTION 8.2.          NOTICES............................................................................16

         SECTION 8.3.          LABOR, OTHER RELATIONS.............................................................16

         SECTION 8.4.          CONSTRUCTION INDEMNITY.............................................................16

         SECTION 8.5.          LANDLORD ALTERATIONS...............................................................16

ARTICLE 9 - REPAIRS...............................................................................................17

         SECTION 9.1.          TENANT'S OBLIGATIONS...............................................................17

         SECTION 9.2.          LANDLORD'S OBLIGATIONS.............................................................17

         SECTION 9.3.          TENANT'S NEGLIGENCE................................................................17

ARTICLE 10 - ASSIGNMENT AND SUBLEASE .............................................................................17

                                       ii
<PAGE>


                                TABLE OF CONTENTS
                                   (CONTINUED)
<CAPTION>
                                                                                                                PAGE
<S>                                                                                                             <C>
         SECTION 10.1.         GENERAL............................................................................17

         SECTION 10.2.         NOTICE AND PROCEDURE...............................................................18

         SECTION 10.3.         LANDLORD'S CONSENT.................................................................19

         SECTION 10.4.         CONDITIONS.........................................................................20

         SECTION 10.5.         LIMITATION ON REMEDIES.............................................................21

         SECTION 10.6.         CONTINUING LIABILITY OF TENANT.....................................................21

         SECTION 10.7.         BANKRUPTCY.........................................................................21

ARTICLE II - DESTRUCTION OR DAMAGE ...............................................................................22

         SECTION 11.1.         GENERAL............................................................................22

         SECTION 11.2.         INSURED CASUALTY...................................................................23

         SECTION 11.3.         UNINSURED CASUALTY.................................................................23

         SECTION 11.4.         TENANT'S ELECTION..................................................................23

         SECTION 11.5.         END OF TERM........................................................................24

         SECTION 11.6.         ABATEMENT OF RENTALS...............................................................24

         SECTION 11.7.         LIABILITY FOR PERSONAL PROPERTY....................................................24

         SECTION 11.8.         WAIVER OF CERTAIN REMEDIES.........................................................25

ARTICLE 12 - EMINENT DOMAIN.......................................................................................25

         SECTION 12.1.         TAKING OF PREMISES.................................................................25

         SECTION 12.2.         TEMPORARY TAKING...................................................................25

         SECTION 12.3.         ABATEMENT OF RENT..................................................................25

         SECTION 12.4.         CONDEMNATION AWARD.................................................................25

ARTICLE 13 - INSURANCE............................................................................................26

                                       iii
<PAGE>


                                TABLE OF CONTENTS
                                   (CONTINUED)
<CAPTION>
                                                                                                                PAGE
<S>                                                                                                             <C>
         SECTION 13.1.         LIABILITY INSURANCE................................................................26

         SECTION 13.2.         TENANT'S PROPERTY INSURANCE........................................................26

         SECTION 13.3.         TENANT'S ADDITIONAL INSURANCE......................................................27

         SECTION 13.4.         INSURANCE CRITERIA.................................................................27

         SECTION 13.5.         EVIDENCE OF COVERAGE...............................................................27

         SECTION 13.6.         WAIVER OF SUBROGATION..............................................................27

ARTICLE 14 - WAIVER INDEMNITY.....................................................................................27

         SECTION 14.1.         WAIVER OF LIABILITY................................................................27

         SECTION 14.2.         TENANT'S INDEMNITY.................................................................28

ARTICLE 15 - DEFAULT..............................................................................................28

         SECTION 15.1.         EVENTS OF DEFAULT..................................................................28

         SECTION 15.2.         LANDLORD'S REMEDIES................................................................29

         SECTION 15.3.         LATE CHARGES; INTEREST.............................................................30

         SECTION 15 4.         LEASE CONTINUES UNTIL TERMINATION..................................................31

         SECTION 15.5.         RELETTING PREMISES.................................................................31

         SECTION 15.6.         CURE BY LANDLORD...................................................................31

         SECTION 15.7.         LANDLORD'S DEFAULT.................................................................31

         SECTION 15.8.         REMEDIES CUMULATIVE................................................................32

         SECTION 15.9.         SECURITY DEPOSIT...................................................................32

ARTICLE 16 - SUBORDINATION........................................................................................33

         SECTION 16.1.         SUBORDINATION OF LEASE.............................................................33

         SECTION 16.2.         SUBORDINATION OF DEED OF TRUST.....................................................34


                                       iv
<PAGE>


                                TABLE OF CONTENTS
                                   (CONTINUED)
<CAPTION>
                                                                                                                PAGE
<S>                                                                                                             <C>
         SECTION 16.3.         APPROVAL BY MORTGAGEES..............................................................34

ARTICLE 17 - ENTRY BY LANDLORD ....................................................................................34

ARTICLE 18 - OPTION TO EXTEND TERM ................................................................................35

         SECTION 18.1.         OPTION..............................................................................35

         SECTION 18.2.         LANDLORD'S USE.....................................................................35

         SECTION 18.3.         FAIR MARKET RENTAL.................................................................36

ARTICLE 19 - MISCELLANEOUS........................................................................................37

         SECTION 19.1.         HOLDING OVER.......................................................................37

         SECTION 19.2.         LANDLORD'S INTEREST................................................................38

         SECTION 19.3.         QUIET ENJOYMENT....................................................................38

         SECTION 19.4.         LANDLORD'S LIABILITY...............................................................38

         SECTION 19.5.         NO MERGER..........................................................................38

         SECTION 19.6.         SURRENDER OF PREMISES..............................................................38

         SECTION 19.7.         ESTOPPEL CERTIFICATE...............................................................39

         SECTION 19.8.         NO LIGHT, AIR OR VIEW EASEMENT.....................................................39

         SECTION 19.9.         NOTICES............................................................................39

         SECTION 19.10.        SUCCESSORS.........................................................................40

         SECTION 19.11.        ATTORNEYS' FEES....................................................................40

         SECTION 19.12.        WAIVER.............................................................................40

         SECTION 19.13.        CAPTIONS...........................................................................40

         SECTION 19.14.        TIME OF ESSENCE....................................................................40

         SECTION 19.15.        INTEREST RATE......................................................................40

                                       v
<PAGE>


                                TABLE OF CONTENTS
                                   (CONTINUED)
<CAPTION>
                                                                                                                PAGE
<S>                                                                                                             <C>
         SECTION 19.16.        GOVERNING LAW......................................................................40

         SECTION 19.17.        ENTIRE AGREEMENT...................................................................40

         SECTION 19.18.        INVALIDITY.........................................................................41

         SECTION 19.19.        AUTHORITY..........................................................................41

         SECTION 19.20.        NO OFFER...........................................................................41

         SECTION 19.21.        NO REPRESENTATIONS OR WARRANTIES...................................................41

         SECTION 19.22.        BROKERS............................................................................41

         SECTION 19.23.        AMENDMENTS.........................................................................42

         SECTION 19.24.        NAME...............................................................................42

         SECTION 19.25.        SIGNS, DIRECTORY...................................................................42

         SECTION 19.26.        PARKING............................................................................42

         SECTION 19.27.        BUILDING ACCESS....................................................................42

         SECTION 19.28.        LANDLORD...........................................................................42

         SECTION 19.29.        CONFERENCE ROOMS...................................................................43

         SECTION 19.30.        SECURITY, CUSTOMER SERVICE AREA....................................................43

         SECTION 19.31.        ANTENNA............................................................................44

         SECTION 19.32.        EXHIBITS...........................................................................45
</TABLE>

                                       vi
<PAGE>

                             300 CONSTITUTION DRIVE
                                  OFFICE LEASE

                  THIS OFFICE LEASE is made and entered into as of November 24,
1999, by and between TYCO ELECTRONICS CORPORATION, a Pennsylvania corporation
("Landlord"), and INTERWAVE COMMUNICATIONS, INC., a Delaware corporation
("Tenant").

                              ARTICLE 1 - PREMISES

                  Section 1.1       PREMISES. Landlord hereby leases to Tenant,
and Tenant hereby leases from Landlord, for the term and subject to the terms
and provisions contained in the Basic Lease Information and hereinafter set
forth, those certain premises shown on the floor plan attached hereto as EXHIBIT
A ("Premises"), which Premises are located on the first and second floors of the
office building referred to in the Basic Lease Information (such office building
is hereinafter referred to as the "Building"). The Building is located on that
certain real property commonly known as 300 Constitution Drive, Menlo Park,
California, and such real property, together with the Building, the other office
buildings owned by Landlord and located on such real property and all Common
Area (as defined below) and other improvements located thereon, are sometimes
hereinafter referred to as the "Project."

                  Section 1.2       AREA OF PREMISES. Landlord and Tenant agree
that the area of the Premises is the square footage specified therefor in the
Basic Lease Information, and, without limiting the foregoing, Tenant
acknowledges that the rentable area of the Premises includes an allocation of
the Common Area. Such square footage of the Premises shall be conclusive for all
purposes under this Lease. Landlord and Tenant further agree that, for all
purposes under this Agreement, Tenant's Share is the percentage therefor
specified in the Basic Lease Information.

                  Section 1.3       COMMON AREA.

                  (a)      The "Common Area" shall mean all streets, driveways,
entrances, exits, sidewalks, ramps, corridors, halls, stairs, elevators,
elevator equipment, landscaped areas, parking areas, loading and unloading
areas, delivery areas, Building and Project office facilities, fire vestibules,
foyers, lobbies, electric, telephone and telecommunications closets and risers,
common restrooms, mechanical rooms, service rooms, janitor's closets, light
wells, pipes, ducts, flues, chutes, conduits, wires, columns and all other
areas, facilities or improvements located in the Building or Project and
provided by Landlord for the benefit and non-exclusive use of Landlord. Tenant,
the other tenants and occupants of the Building and Project and their respective
employees, agents and invitees. Notwithstanding the foregoing, the Common Area
shall not include any of the foregoing areas, facilities or improvements which
are provided for by Landlord for the exclusive use or benefit of Landlord's
employees, agents or invitees, or which are


                                      1
<PAGE>

provided by Landlord the exclusive use or benefit of any other tenant or other
occupant of the Building or any other portion of the project.

                  (b)      Tenant's use and occupancy of the Premises under this
Lease shall include the non-exclusive right to use the Common Area in common
with Landlord; Landlord's employees, agents or invitees; other tenants and
occupants of the Building and Project; and other parties entitled to use the
Common Area, subject to the provisions of this Lease and to the Project rules
and regulations hereinafter described. Tenant shall not use the Common Area for
the conduct of its business or for the storage, either permanent or temporary,
of any materials, supplies, equipment or refuse, and shall keep the Common Area
free and clear of any obstructions created or permitted by Tenant or resulting
from the conduct of Tenant's business on the Premises.

                  Section 1.4       CONDITION OF PREMISES.

                  (a)      Tenant acknowledges and agrees that, as of the date
of this Lease, Tenant has conducted its own investigation of the Premises, the
physical condition thereof, including accessibility and location of utilities,
improvements and the presence or absence of Hazardous Materials (as defined
below), and any other matters relating to the Premises, the Building or the
Project which in Tenant's judgment might affect or influence Tenant's use of the
Premises or Tenant's willingness to enter into this Lease. Tenant recognizes
that Landlord would not lease the Premises except on an "as is" basis and
acknowledges that, except as otherwise expressly set forth in this Lease,
Landlord has made no representations or warranties of any kind in connection
with the improvements to, or physical conditions on, or bearing on the use of,
the Premises, the Building or the Project. Tenant shall rely solely on Tenant's
own inspection and examination of such items and not on any representations or
warranties of Landlord or its agents, employees or contractors, express or
implied. Landlord shall have the right to remove from the Premises the computer
and communications systems embodied by the software and hardware at the Premises
which link the Premises to other facilities of Landlord. Such removal shall
occur prior to December 15, 1999, in the portion of the Premises other than the
Landlord Retained Area (as defined below), and prior to February 1, 2000, in the
Landlord Retained Area.

                  (b)      Tenant acknowledges and agrees that Tenant has
examined and inspected all matters with respect to real property taxes, personal
property taxes, operating expenses, costs of insurance, permitted uses, zoning,
private covenants, conditions and restrictions, and all other matters which, in
Tenant's judgment, might bear upon the value and suitability of the Premises for
Tenant's purposes or Tenant's willingness to enter into this Lease. Tenant has
and will rely solely on Tenant's own inspection and examination of such items.

                  (c)      Notwithstanding  the  provisions  of this  Section
1.4. Landlord hereby expressly discloses to Tenant that full telephone service
(that is, installation of a main


                                        2
<PAGE>


point of entry within Building I, with lines from such point of entry connected
directly to Pacific Bell) shall be available on or before January 1, 2000. If
full telephone service is not available until subsequent to January 1, 2000,
Tenant will continue to pay the reduced Monthly Base Rent set forth in Section
3.1 below, until the later of (i) fifteen (15) days after the date on which full
telephone service is available, or (ii) January 31, 2000.

                         ARTICLE 2 - TERM AND POSSESSION

                  Section 2.1       TERM.

                  (a)      This Lease shall become effective upon execution by
Landlord and Tenant. The term of this Lease ("Term") shall commence on the date
calculated as provided in subparagraph (b) below ("Commencement Date"), and
shall continue for a period of five (5) years, one month thereafter, unless
earlier terminated in accordance with this Lease or unless extended as
hereinafter provided. If Landlord shall not deliver possession of the Premises
to Tenant in the manner provided under subparagraph (b) below on or before the
"Scheduled Commencement Date" specified in the Basic Lease Information for any
reason whatsoever. Landlord shall not be liable to Tenant by reason thereof and,
except as provided below, this Lease and the parties' obligations hereunder
shall not be rendered void or voidable thereby or otherwise affected in any
manner, except that Tenant's obligation to pay Monthly Base Rent (as defined
below) and other amounts payable by Tenant under this Lease shall not commence
until the Commencement Date. In addition, no delay by Landlord in the delivery
of possession of the Premises to Tenant shall extend the Term or any obligation
of Landlord hereunder. In the event that the Commencement Date has not occurred
prior to March 1, 2000, Tenant shall have the right to terminate this Lease by
delivering written notice to Landlord of such election to terminate on or before
ten (10) days thereafter, in which event any sums paid by Tenant to Landlord
shall be immediately returned to Tenant.

                  (b)      The Commencement Date shall be the date upon which
Landlord delivers possession of the Premises, other than the Landlord Retained
Area, to Tenant. At such time as the Commencement Date has been established, at
Landlord's request, Landlord and Tenant shall execute a written acknowledgment
of the Commencement Date. For the purposes of this Lease, the term "Landlord
Retained Area" shall mean the portion of the first floor of the Premises
occupied by Landlord's payroll group and containing approximately 1,340 square
feet of rentable area, as shown on EXHIBIT A. Landlord shall deliver possession
of the Landlord Retained Area to Tenant on or before February 1, 2000. If
Landlord shall fail to deliver possession of the Landlord Retained Area to
Tenant on or before February 1, 2000, Tenant's obligation to pay to Landlord
Monthly Base Rent with respect to the Landlord Retained Area shall be abated
until such time as Landlord shall deliver possession of the Landlord Retained
Area to Tenant. If Landlord does not deliver possession of the Landlord Retained
Area to Tenant on or before March 1, 2000. Tenant's obligation to pay to
Landlord Monthly Base Rent with


                                     3
<PAGE>


respect to the Landlord Retained Area shall be abated for each day of such delay
in delivery beyond March 1, 2000.

                  (c)      On the date of Landlord's delivery of possession of
the Premises to Tenant pursuant to this Section, the portion of the Premises so
delivered shall be clean and the Building systems located therein shall be in
good operating condition. Tenant's occupancy of the Premises (whether before or
after the Scheduled Commencement Date) shall constitute Tenant's acceptance of
the Premises and acknowledgment that the Premises are in such condition and
otherwise in good order and satisfactory to Tenant.

                  Section 2.2       IMPROVEMENTS Without limiting any other
provisions of this Agreement, Tenant expressly acknowledges and agrees that
Landlord shall have no obligation whatsoever to construct any tenant
improvements or other alterations, additions or improvements in or to the
Premises or Building, or, apart from Landlord's obligations under Section 2.l(c)
above, otherwise to prepare the Premises or Building for Tenant's occupancy.

                                ARTICLE 3 - RENT

                  Section 3.1       BASE RENT. Tenant shall pay to Landlord
throughout the term of this Lease, in lawful money of the United States, Monthly
Base Rent in the following amounts:

<TABLE>

                   PERIOD OF TERM                     MONTHLY BASE RENT
                   --------------                     -----------------
                <S>                                   <C>
                12/15/1999 - 1/31/2000                     $36,601.43
                  2/1/2000 - 2/29/2000                    $165,877.38
                  3/1/2000 - 1/31/200l                    $169,026.00
                  2/1/2001 - 1/31/2002                    $175,787.00
                  2/1/2002 - l/31/2003                    $182,819.00
                  2/1/2003 - 1/31/2004                    $190,132.00
                  2/1/2004 - 1/31/2005                    $197,737.18

</TABLE>

                  Tenant shall pay to Landlord the Monthly Base Rent without
notice or demand in advance, beginning on the Commencement Date and on the first
day of each calendar month thereafter during the Term. Concurrently with the
execution of this Lease by Tenant, and as a condition to its effectiveness,
Tenant shall pay to Landlord the advance rental specified in the Basic Lease
Information.

                  Section 3.2        PAYMENT. All payments required to be made
by Tenant under this Lease shall be made without any setoff, deduction or
counterclaim whatsoever and shall be made payable to and delivered to Landlord
at the office of Landlord in the Building or such other place as Landlord may
designate.


                                   4
<PAGE>

                  Section 3.3       PARTIAL MONTHS. If the Commencement Date is
a day other than the first day of a calendar month or if the Term expires or the
Lease is terminated on a day other than the last day of a calendar month, then
the Monthly Base Rent for the first and last fractional months of the Term shall
be prorated on the basis of a thirty (30) day month.

                      ARTICLE 4 - TAX, INSURANCE ADJUSTMENT

                  Section 4.1       EXCESS TAXES. Tenant shall pay to Landlord,
in addition to the Monthly Base Rent and for each calendar year of the Term, an
amount equal to the excess, if any, of Tenant's Share of Taxes (as defined
below) paid or incurred by Landlord during such calendar year, over the Base Tax
Amount (such excess is hereinafter referred to as the "Excess Taxes"). At or
after the Commencement Date, as to the then-current calendar year, and at or
after the commencement of any subsequent calendar year. Landlord shall have the
right to notify Tenant of the amount which Landlord reasonably estimates to be
the monthly or quarterly installments of the Excess Taxes for such calendar
year, and the amount thereof shall be payable by Tenant to Landlord together
with payments of Monthly Base Rent on a monthly or quarterly basis, as
applicable. Within one hundred twenty (120) days after the end of each calendar
year, or as soon thereafter as is practicable, Landlord shall give to Tenant a
written statement of the Excess Taxes for such calendar year ("Tax Statement").
If the Excess Taxes as shown on the Tax Statement are greater or less than the
total amounts actually paid by Tenant on a monthly or quarterly basis, as
applicable, during the year covered by such Tax Statement, then Tenant shall pay
in cash any sums owed Landlord within ten (10) business days thereafter, or, if
applicable. Tenant shall receive a credit against any the Excess Taxes next
accruing for any sums owed Tenant. If the Term of this Lease commences on a date
other than the first day of the calendar year or expires or is terminated on a
day other than the last day of a calendar year, the amount of Taxes with respect
to which Tenant shall be obligated to pay its share during the year in which the
Lease commences or expires or is terminated shall be prorated on the basis which
the number of days in the calendar year within the Term bears to three hundred
sixty (360). Following expiration of the calendar year in which the Term expires
or is terminated, Landlord shall give a final Tax Statement to Tenant for such
calendar year. If the Excess Taxes as shown on such final Tax Statement are
greater or less than the total amounts actually paid by Tenant as Excess Taxes
during the year covered by the final Tax Statement, then within ten (10)
business days thereafter the appropriate party shall pay to the other party any
sums owed.

                  Section 4.2        TAXES. For the purpose of this Lease, the
term "Taxes" shall mean and include all taxes, assessments and charges
(including costs and expenses of contesting the amount or validity thereof by
appropriate administrative or legal proceedings) levied upon or with respect to
the Building, the Project or any personal property of Landlord therein used in
connection with the management, operation,


                                   5
<PAGE>

maintenance or repair of the Building or the Project (and not in connection
with Landlord's core business operations conducted within the Project), or
Landlord's interest in the Building, the Project or such personal property,
including all real property taxes and general and special assessments;
charges, fees, levies or assessments for transit, housing, police, fire or
other governmental services or purported benefits to the Building or the
Project; service payments in lieu of taxes; environmental surcharges; excise
taxes; gross receipts taxes; gross income taxes; rent taxes; sales and/or use
taxes; employee taxes; water and sewer taxes; any tax, fee or excise on the
act of entering into this Lease, on the use or occupancy of the Building, the
Project or any part thereof, or upon or measured by the rent payable under
any lease or in connection with the business of renting space in the Building
or the Project; and all other governmental impositions of any kind and nature
whatsoever, regardless of whether now customary or within the contemplation
of the parties hereto and regardless of whether resulting from increased rate
and/or valuation, or whether extraordinary or ordinary, general or special,
unforeseen or foreseen, or similar or dissimilar to any of the foregoing,
which may now or hereafter be levied or assessed against Landlord by the
United States of America, the State of California, the County of San Mateo,
the City of Menlo Park or any political subdivision, public corporation,
district or other political or public entity, and any other tax, fee or other
excise, however described, that may be levied or assessed as a substitute
for, or as an addition to (in whole or in part) any other such taxes. For the
purposes of this Lease, the term "Tenant's Share of Taxes" shall mean the
product of Tenant's Tax Share (as hereinafter defined), multiplied by the
amount of Taxes for the year in question. For the purposes of this Lease.
"Tenant's Tax Share" shall mean the percentage obtained by dividing the
rentable area of the Premises by the sum of the rentable area of the Building
and the rentable area of all other building improvements located on the
assessor's tax parcel in which the Building is located.

         Section 4.3       ADDITIONAL TAXES. In addition to the Monthly Base
Rent and other amounts payable by Tenant hereunder, to the extent that Tenant
shall not have paid any such amounts directly to the appropriate parts therefor,
Tenant shall reimburse Landlord upon demand for any and all taxes, surcharges,
levies, assessments, fees and charges paid by Landlord, whether or not now
customary or within the contemplation of the parties hereto: (a) upon, measured
by or reasonably attributable to the cost or value of Tenant's equipment,
furniture, fixtures and other personal property located in the Premises, or the
cost or value of any leasehold improvements, regardless of whether title to such
improvements shall be in Tenant or Landlord; (b) upon or with respect to the
possession, leasing, operation, management, maintenance, alteration, repair, use
or occupancy by Tenant of the Premises or any portion thereof; or (c) upon this
Lease transaction or any document to which Tenant is a party creating or
transferring an interest or an estate in the Premises. In the event that it
shall not be lawful for Tenant to reimburse Landlord for the additional taxes
payable hereunder, but it shall be lawful to increase the monthly rental payable
under this Lease in order to take into account Landlord's payment of such
additional taxes, the monthly rental payable to Landlord


                                   6
<PAGE>

shall be revised to net to Landlord the same net rental without reimbursement of
such additional taxes as would have been received by Landlord with reimbursement
of such additional taxes. Tenant shall have no obligation to reimburse Landlord
for any Taxes upon the net income of Landlord.

                  Section 4.4        EXCESS INSURANCE COSTS. Tenant shall pay to
Landlord, in addition to the Monthly Base Rent and for each calendar year of the
Term, an amount equal to the excess, if any, of Tenant's Share of Insurance
Costs (as defined below) paid or incurred by Landlord during such calendar year,
over the Base Insurance Amount (such excess is hereinafter referred to as the
"Excess Insurance Costs"). At or after the Commencement Date as to the
then-current calendar year, and at or after the commencement of any subsequent
calendar year, Landlord shall have the right to notify Tenant of the amount
which Landlord reasonably estimates to be the monthly or quarterly installments
of Excess Insurance Costs for such calendar year, and the amount thereof shall
be payable by Tenant to Landlord together with payments of Monthly Base Rent on
a monthly or quarterly basis, as applicable. Within one hundred twenty (120)
days after the end of each calendar year, or as soon thereafter as is
practicable. Landlord shall give to Tenant a written statement of the Excess
Insurance Costs for such calendar year ("Insurance Statement"). If the Excess
Insurance Costs as shown on the Insurance Statement are greater or less than the
total amounts actually paid by Tenant as Excess Insurance Costs on a monthly or
quarterly basis, as applicable, during the year covered by such Insurance
Statement, then Tenant shall pay in cash any sums owed Landlord within ten (10)
business days thereafter, or, if applicable, Tenant shall receive a credit
against any the Excess Insurance Costs next accruing for any sums owed Tenant.
If the Term of this Lease commences on a date other than the first day of the
calendar year or expires or is terminated on a date other than the last day of
the calendar year, the amount of Insurance Costs with respect to which Tenant
shall be obligated to pay its share during the year in which the Lease commences
or expires or is terminated shall be prorated on the basis for which the number
of days in the calendar year within the Term bears to three hundred sixty (360).
Following the expiration of the calendar year in which the Term expires or is
terminated. Landlord shall give a final Insurance Statement to Tenant for such
calendar year. If the Excess Insurance Costs as shown on such final Insurance
Statement are greater or less than the total amounts actually paid by Tenant as
Excess Insurance Costs during the year covered by the final Insurance Statement,
then within ten (10) business days thereafter the appropriate party shall pay to
the other party any sums owed.

                  Section 4.5        INSURANCE COSTS. For the purposes of this
Lease, the term "Insurance Costs" shall mean and include all costs and expenses,
including premium charges, paid or incurred by Landlord for insurance maintained
by Landlord with respect to the Premises, the Building and/or the Project,
including, without limitation, all risk, commercial general liability,
automobile liability, property damage, worker's compensation, employer's
liability, earthquake, flood and such other insurance in such


                                   7
<PAGE>

forms of coverage and on such amounts as Landlord, in its sole discretion, shall
elect to maintain with respect to the Building or Project. In the case of
blanket insurance policies covering the Project and other property of Landlord,
Insurance Costs shall include the costs and expenses thereof allocated by
Landlord to the Project. For purposes of this Lease, the term "Tenant's Share of
Insurance Costs" shall mean the product of Tenant's Insurance Share (as
hereinafter defined) multiplied by the amount of the Insurance Costs for the
year in question. For the purposes of this Lease "Tenant's Insurance Share"
shall mean the percentage obtained by dividing the rentable area of the Premises
by the sum of the rentable area of the Building and the rentable area of all
other building improvements (including those occupied by Landlord and its
affiliates) within the Project.

                        ARTICLE 5 -INTENTIONALLY OMITTED

                                 ARTICLE 6 - USE

                  Section 6.1        GENERAL. Tenant shall use the Premises only
for the purposes specified in the Basic Lease Information and for no other
purposes. Tenant, at its own cost and expense, shall obtain any and all
licenses, permits, authorizations and approvals of governmental authorities
required in order to enable Tenant lawfully to conduct in the Premises any such
use. Nothing contained in this Lease shall grant to Tenant the exclusive right
to conduct within the Building, the Project or the Premises the business to be
conducted by Tenant in the Premises, or otherwise limit the right of Landlord to
lease space within the Building or the Project to such tenants and for such
purposes as Landlord, in its sole discretion, shall deem appropriate.

                  Section 6.2       NUISANCE OR WASTE. Tenant shall not do or
permit to be done in or about the Premises anything which will in any way
obstruct or interfere with the rights of other tenants or occupants of the
Building or the Project or injure or annoy them or use or allow the Premises to
be used for any improper purpose, and Tenant shall not cause, maintain or permit
any nuisance in, on or about the Premises. Tenant shall not commit or suffer the
commission of any waste in, on or about the Premises. Tenant shall not use or
operate any equipment, machinery or apparatus within the Premises which will (a)
injure, vibrate or shake the Premises, the Building or the Project, (b) overload
existing electrical systems or other utilities or equipment servicing the
Premises, the Building or the Project, or (c) impair the efficient operation of
the sprinkler system (if any) or the HVAC equipment (if any) within or servicing
the Premises, the Building or the Project. All noises or odors generated by
Tenant's use of the Premises shall be muffled or contained in such manner such
that they do not interfere with the use or occupancy of other tenants or
occupants of the Building or the Project.

                  Section 6.3        COMPLIANCE WITH LAW. Tenant shall not use
the Premises or permit anything to be done in, on or about the Premises which
will in any way conflict (a) with any statute, ordinance, rule or regulation of
governmental authorities now in force or which may hereafter be enacted or
promulgated, or (b) any provisions of any


                                   8
<PAGE>

private covenants, conditions, restrictions, equitable servitudes or rules or
regulations which may now or hereafter affect the Premises, the Building, the
Project or any portion thereof (collectively, "CC&Rs") if any.  Tenant shall not
do or permit anything to be done in or about the Premises, or bring or keep
anything therein, which will in any way increase the rate of fire insurance upon
the Project, the Building, the Premises or any of their contents. Tenant, at its
sole cost and expense, shall promptly comply with (i) all statutes, ordinances,
rules and regulations of governmental authorities applicable to the Premises or
Tenant's use or occupancy thereof and now in force or which may hereafter be in
force regardless of the nature or extent thereof, (ii) all CC&Rs, if any, and
(iii) the requirements of any board of fire underwriters or other similar body
now or hereafter constituted relating to or affecting the condition, use, or
occupancy of the Premises. Notwithstanding the foregoing, in order to comply
with any such statutes, ordinances, roles and regulations of governmental
authorities applicable to the Premises or Tenant's use or occupancy thereof,
Tenant shall not be obligated to make any alteration, addition, improvement or
repair to the Premises, unless the obligation to make such alteration, addition,
improvement or repair arises by reason of Tenant's particular use of the
Premises, or results from any other alteration, addition, improvement or repair
made by Tenant to the Premises. The judgment of any court of competent
jurisdiction or the admission of Tenant in an action against Tenant, whether
Landlord be a party thereto or not, that Tenant has violated any such statute,
ordinance, rule or regulation shall be conclusive of such violation as between
Landlord and Tenant.

         Section 6.4       HAZARDOUS MATERIALS.

                  (a)      Without limiting the generality of the provisions of
Section 6.3, Tenant, at its sole cost and expense, shall comply with all
statutes, ordinances, rules and regulations of governmental authorities relating
to the storage, use, transportation, release and/or disposal on or about the
Premises or the Project by Tenant, its employees, agents, contractors and
invitees, of radioactive materials, hazardous waste, toxic or contaminated
substances or similar materials, including, without limitation, any substances
which are "hazardous substances" "hazardous waste" "hazardous materials" or
"toxic substances" under applicable federal, state and local statutes,
ordinances, rules or regulations (collectively, "Hazardous Materials"). Tenant
shall not store, use, transport, release or dispose of any Hazardous Materials
in, on, from or about the Premises without the prior written consent of
Landlord. Notwithstanding the foregoing, Landlord's prior written consent shall
not be required for Tenant's use on the Premises of substances and materials
typically used in office environments, such as office and cleaning supplies in
customary and reasonable amounts and used in strict compliance with all
statutes, ordinance, rules and regulations of governmental authorities relating
to Hazardous Materials. Tenant shall be solely responsible for, and shall
indemnify, defend and hold Landlord and its officers, directors, shareholders,
partners, members, agents, employees, contractors, invitees, representatives,
successors and assigns harmless from and against, any and all losses, costs,
claims, damages, liabilities and causes of action (including


                                   9
<PAGE>

attorneys' fees and consultants' fees and costs, and the costs of any
investigation, monitoring and remediation) arising out of or in connection with
the storage, use, transportation, release or disposal of Hazardous Materials by
Tenant, its employees, agents, contractors and invitees, including any claims
for the clean-up or remediation of any such Hazardous Materials. Tenant shall
provide to Landlord written notice of any communication received by Tenant from
any governmental authority or other party alleging the existence of Hazardous
Materials in, on, under or about the Premises, the Building or the Project, or
any alleged violation of environmental laws with respect to the Premises, the
Building or the Project. Without limiting any other provision of this Lease,
Tenant shall provide Landlord with access to the Premises during all reasonable
times in order to enable Landlord to conduct any inspection, monitoring,
remediation, removal or repair related to the presence or alleged presence of
Hazardous Materials in, on, under or about the Premises, the Building or the
Project. Any such inspection, monitoring, remediation, removal or repair on
Premises shall be conducted by Landlord in a manner calculated to minimize
interference with Tenant's operations to the extent reasonably possible.

                  (b)      Landlord shall indemnify, defend and hold Tenant
harmless from and against any and all losses, costs, claims, damages,
liabilities and causes of action (including attorneys' fees and costs) arising
out of or in connection with any Hazardous Materials which first came to be
located in, on or under the Project prior to the date of this Lease. Landlord
hereby discloses to Tenant that certain asbestos-containing materials are
located in the Building as described in that certain memorandum from Kristin
Stiles dated July 15, 1999, a copy of which has previously been delivered to
Tenant.

                  (c)      The rights of Landlord under this Section 6.4 or
otherwise contained in this Lease shall be in addition to any other rights and
remedies of Landlord against Tenant under any other document or instrument now
or hereafter executed by Tenant, or at law or in equity (including any right of
reimbursement or contribution pursuant to the Comprehensive Environmental
Response. Compensation and Liability Act of 1980, 42 U.S.C. section 9601 ET
SEQ., as heretofore or hereafter amended from time to time).

                  Section 6.5       EXISTING CONDITION. Tenant shall accept the
Premises subject to all applicable statutes, ordinances, rules and regulations
of governmental authorities governing and regulating the use or occupancy of the
Premises, including, without limitation, all applicable zoning, planning,
environmental and land use statutes, ordinances, rules and regulations. Tenant
acknowledges that neither Landlord nor Landlord's employees, agents or
contractors have made any representation or warranty as to the suitability of
the Premises for the conduct of Tenant's business or the consistency of Tenant's
proposed use of the Premises with any applicable zoning, planning, environmental
or land use statutes, ordinances, rules or regulations.


                                   10

<PAGE>

                  Section 6.6        RULES AND REGULATIONS. Tenant shall observe
and comply with all Project rules and regulations that Landlord shall from time
to time reasonably and uniformly promulgate. Landlord reserves the right from
time to time to promulgate reasonably and uniformly additional rules and
regulations for the Project or Building, and to make additions and modifications
to such rules and regulations, and such additional rules and regulations and/or
additions and modifications to such rules and regulations shall be binding upon
Tenant upon delivery of a copy thereof to Tenant. Landlord shall not be
responsible to Tenant for the non-performance of any rules and regulations by
any other tenants or occupants of the Building or the Project.

                  Section 6.7       COMMON AREA PROVISIONS. Landlord shall have
the right, from time to time, temporarily to close portions of the Common Area
in order to prevent a dedication thereof to the public or the perfection of any
prescriptive rights therein or to perform repair or maintenance on such portion
of the Common Area; and to change the size, shape, location and extent of the
areas, facilities and improvements included in the Common Area, including
changes in the location of driveways, entrances, exits, elevators, stairs,
corridors, common restrooms and other portions of the Common Area. Landlord's
exercise of such rights shall not subject Landlord to any liability therefor nor
shall Tenant be entitled to any compensation or any diminution or abatement of
rent, provided that Landlord exercises such rights in such manner as to minimize
any interference with Tenant's use and enjoyment of the Premises to the extent
reasonably possible. In no event shall Landlord's exercise of such rights be
deemed to be a constructive or actual eviction of Tenant, or a breach of
Landlord's covenant of quiet enjoyment.

                       ARTICLE 7 - SERVICES AND UTILITIES

                  Section 7.1       GENERAL. Landlord shall:

                  (a)      Operate or cause the operation of the HVAC system
serving the Premises between the hours of 7:00 a.m. and 7:00 p.m., Monday
through Friday, and 9:00 a.m. and 1:00 p.m., Saturday, public holidays
excepted, at such temperatures and in such amounts as Landlord determines are
reasonably required for the comfortable occupancy of the Premises, or as may be
permitted or controlled by applicable statutes, ordinances, rules and
regulations of governmental authorities. Tenant agrees to cooperate fully with
Landlord at all times and to abide by all regulations and requirements which
Landlord may prescribe for the proper function and protection of the HVAC
system. Landlord shall not be responsible for the failure of the HVAC system to
perform its function due to Tenant's failure to keep all window coverings in the
Premises closed whenever the HVAC system is in operation, Tenant's arrangement
of partitioning in the Premises, any use of any heat-generating machinery or
equipment in the Premises, any occupancy of the Premises by an excessive number
of persons, or Tenant's failure to keep all HVAC vents within the Premises free
of obstruction;

                                     11
<PAGE>

                  (b)      Make customary arrangements with public utilities
and/or governmental agencies to furnish electric current to the Premises in
amounts sufficient for normal lighting by overhead fluorescent fixtures and for
normal use of typewriters and other office business machines of similar low
electrical consumption. Landlord shall have no obligation to install dedicated
circuits or other special circuitry or wiring. Tenant shall advise Landlord
prior to execution of this Lease and thereafter within five (5) days after
written request therefor from Landlord of the nature and quantity of all lights,
equipment and machines using electricity in the Premises and shall permit
Landlord and its agents to make periodic inspections of all facilities using
electricity located within the Premises. If Landlord reasonably determines that
Tenant is using excessive electricity, Landlord shall have the right to install
an electric current meter in or with respect to the Premises in order to measure
the amount of electricity consumed on the Premises. The cost of such meter, and
any conduits, wiring, panels and other equipment required in connection with
such meter, and the installation, maintenance and repair thereof, shall be paid
for by Tenant, and Tenant shall pay to Landlord promptly upon demand all such
costs, as well as the cost of any excessive electricity consumed by Tenant;

                  (c)      Provide access to warm and cold water in the
restrooms on the floor or floors on which the Premises are located for drinking
and lavatory purposes only if Tenant requires, uses or consumes water for any
purposes in addition to ordinary drinking and lavatory purposes. Landlord may
install a separate water meter for the Premises in order to measure the amount
of water consumed in the Premises. Tenant shall bear the cost and expense of
installation, repair and maintenance of such meter. Tenant shall pay for water
consumed, as shown on such meter, as and when bills are rendered, and if Tenant
shall fail to pay such charges. Landlord may pay such charges on Tenant's behalf
and recover such amounts from Tenant, together with interest thereon at the
Interest Rate (as defined below);

                  (d)      Make customary arrangements with public utilities
and/or governmental agencies to furnish to the Premises natural gas and sewer
service in amounts sufficient for the ordinary use of the Premises for the
purposes permitted under this Lease;

                  (e)      Provide janitorial service to the individual offices
on the Premises three (3) days per week, and to the bathrooms, conference areas
and other common areas on the Premises five (5) days per week, such service to
be comparable to the janitorial service provided by Landlord to its own office
premises in the Project as of the date of this Lease;

                  (f)      Operate, repair, maintain, clean and light the Common
Area. Notwithstanding the foregoing, Tenant acknowledges and agrees that
Landlord shall not be obligated to provide any security services with respect to
the Premises, the Building or the Project, and Tenant shall make all such
security arrangements as Tenant shall deem


                                      12
<PAGE>

necessary or appropriate with respect to Tenant's use or occupancy of the
Premises; all such security arrangements shall be subject to Landlord's prior
written approval. In addition, Landlord shall not be liable to Tenant for losses
due to theft or burglary, or for any other damage done, by unauthorized persons
in the Building or the Project; and

                  (g)      Provide access to the Premises on a twenty-four (24)
hour per day, seven (7) day per week basis, subject to such security procedures
for the Building and Project as are presently in effect and as Landlord shall
establish from time to time; such security procedures may include, without
limitation, requiring Tenant, its employees, agents, customers and invitees to
identify themselves to Landlord's security personnel or otherwise satisfy the
reasonable requirements of such security personnel, and/or sign a pre-approved
sign-in sheet after normal business hours for the Building or Project and on
weekends and public holidays.

                  Section 7.2       UTILITY SERVICES.

                  (a)      Tenant shall pay to Landlord, in addition to the
Monthly Base Rent, any amount by which the Utility Charges (as defined below)
exceed the Utility Allowance (such excess is hereinafter referred to as the
"Excess Utility Charges"). Landlord shall calculate the amount of Excess
Utility Charges payable by Tenant on a quarterly basis throughout the Term, and
Tenant shall pay such Excess Utility Charges to Landlord on the date for payment
of the next installment of Monthly Base Rent. For purposes of this Lease, the
term "Utility Charges" shall mean the charges to Landlord for electrical,
natural gas, water and sewer service furnished to or consumed on the Premises
during the Term.

                  (b)      Tenant shall pay, prior to delinquency, directly to
the appropriate party therefor, the costs of and charges for utilities other
than those specified in subparagraph (a) above and for other services furnished
to or consumed in or about the Premises during the Term. If any such utilities
or services are not separately metered to Tenant. Tenant shall pay a reasonable
proportion, to be determined by Landlord, of all charges jointly metered with
other premises in the Building or Project.

                  Section 7.3       SUPPLEMENTARY SERVICES. Tenant shall pay
Landlord upon demand, at the charges established by Landlord from time to time
which reflect Landlord's cost of providing such services, for all supplementary
services provided by Landlord to Tenant at Tenant's request, which services are
in addition to those which Landlord is obligated to provide under this Lease,
together with an administrative fee payable to Landlord in an amount equal to
five percent (5%) of such charges. Such supplementary services shall include,
without limitation, providing HVAC service, janitorial service and other
services during hours other than ordinary business hours and/or providing HVAC
service and utility services in amounts reasonably considered by Landlord to be
in excess of the normal and customary usage thereof for the use of the Premises
authorized by this Lease.


                                      13
<PAGE>

                  Section 7.4        INTERRUPTION OF ACCESS, USE OR SERVICES.
Landlord shall not be liable for any failure to provide access to the Premises,
to assure the beneficial use of the Premises or to furnish any services or
utilities to the Premises when such failure is caused by any act of God or the
elements; shortage or unavailability of necessary materials, supplies or labor;
shortage of or interruption in transportation facilities; riots; civil
disturbances; insurrection; war; court order; public enemy; accidents; breakage;
strikes; lockouts; other labor disputes; the making of repairs, alterations or
improvements to the Premises, the Building or the Project; the inability to
obtain an adequate supply of fuel, gas, steam, water, electricity, labor or
other supplies; Y2K problems; or by any other condition not entirely within
Landlord's reasonable control, and Tenant shall not be entitled to any damages
resulting from such failure or to any diminution or abatement in any rent or
other amounts payable by Tenant hereunder. Landlord shall take commercially
reasonable action to minimize the interruptions so caused and the adverse impact
accruing therefrom to the extent reasonably possible. In no event shall such
failure be construed as a constructive or other eviction of Tenant. If any
governmental authority promulgates or revises any statute, ordinance or
building, fire or other code, or imposes mandatory controls or guidelines on
Landlord or the Building, the Project or any part thereof, relating to the use
or conservation of energy, water, gas, steam, light or electricity or the
provision of any other utility or service provided under this Lease, or if
Landlord is required to make alterations to the Building or the Project in order
to comply with such mandatory controls or guidelines. Landlord may, in its sole
discretion, comply with such mandatory controls or guidelines, or make such
alterations to the Building and/or the Project. If, at any time, owners of a
significant number of the buildings in the Menlo Park/Palo Alto, California area
comparable to the Building have elected to comply voluntarily with any request
or guideline of any appropriate governmental authority, including, without
limitation, the making of alterations to such buildings. Landlord may also
comply with such request or guideline. Neither such compliance (as set forth
in either of the previous two (2) sentences) nor the making of such
alterations shall in any event entitle Tenant to any damages, or any
diminution, or abatement in rent or other amounts payable by Tenant under
this Lease or constitute or be construed as a constructive or other eviction
of Tenant. Tenant shall comply with all mandatory rules, regulations and
requirements promulgated by the applicable governmental authorities or
utility companies concerning the use of utility services, including any
rationing, limitation or other control on the quantity of utilities consumed.

                             ARTICLE 8 - ALTERATIONS

                  Section 8.l       GENERAL.

                  (a)      Tenant shall neither make nor cause or allow to be
made any alterations, additions or improvements (collectively, "Alterations")
in, on or to any portion of the Premises, the Building or the Project, or any
part thereof without the prior written consent of Landlord, which consent shall
not be unreasonably withheld; provided,


                                      14
<PAGE>

however, that Landlord shall have the right to withhold its consent in its sole
discretion with respect to any Alterations affecting the exterior of the
Building, the structural portions of the Building or the Building systems. In
the event that Tenant shall desire to make any Alterations. Tenant shall submit
to Landlord such information as Landlord may reasonably require prior to the
commencement of construction or installation of such Alterations, including,
without limitation, permits, licenses and bonds and evidence of sufficient
contractor's insurance coverage. Landlord shall use reasonable efforts to
notify Tenant of Landlord's approval or disapproval within ten (10) business
days following Tenant's submission of all such information to Landlord. If
Landlord consents to the making of any Alterations. Tenant shall make such
Alterations at Tenant's sole cost and expense, and any contractor selected by
Tenant to make such Alterations must be licensed by the State of California and
must first be reasonably approved in writing by Landlord. If Landlord consents
to the making of any Alterations, in order to compensate Landlord for the cost
of review and approval of the plans and specifications for the Alterations and
for additional administrative costs incurred in monitoring the construction and
installation of the Alterations. Tenant shall pay to Landlord upon demand an
administrative fee in an amount equal to fifteen percent (15%) of the cost of
such Alterations (exclusive of the cost of floor coverings and paint).
Subsequent to obtaining Landlord's consent and prior to commencement of
construction or installation of the Alterations. Tenant shall deliver to
Landlord copies of the building permit and executed construction contract
covering the Alterations. Tenant shall provide, at its sole cost and expense,
such performance and/or payment bonds as Landlord shall require with respect to
the Alterations costing in excess of $250,000. Tenant shall also require its
contractor to maintain insurance in amounts and in such form as Landlord shall
reasonably require. Any Alterations undertaken by Tenant in connection with the
Premises shall be completed in accordance with the plans and specifications
approved by Landlord, shall be carried out in a good, workmanlike and prompt
manner, shall comply with all applicable statutes, ordinances, rules and
regulations of governmental authorities having jurisdiction thereof, and shall
be subject to supervision by Landlord or its agents or contractors.

                  (b)      Tenant shall not use any portion of the Common Area
or any other portion of the Building or the Project other than the Premises in
connection with the making of any Alterations without Landlord's prior written
consent. If any Alterations that Tenant shall construct or install shall result
in Tenant or Landlord being required to make any alterations, additions or
improvements to the Premises, or in Landlord being required to make any
alterations, additions or improvements to other portions of the Building or to
the Project, in any case in order to comply with my applicable statutes,
ordinances, rules or regulations of governmental authorities, including, without
limitation, the Americans with Disabilities Act, or any regulations promulgated
thereunder, or any similar state or local statutes, ordinances, rules and
regulations, then Tenant, at its sole cost and expense, shall be obligated to
make all such alterations, additions or improvements, or, at Landlord's option.
Tenant shall reimburse Landlord upon demand for all costs and expenses incurred
by Landlord in making such alterations,


                                      15
<PAGE>

additions or improvements. Any Alterations shall become the property of Landlord
and shall remain on and be surrendered with the Premises upon the expiration or
earlier termination of this Lease; provided, however, that Tenant shall, if
required by Landlord at the time consent to such Alteration was given by
Landlord (or upon Landlord's demand if Tenant shall not have requested
Landlord's consent to such Alteration), at Tenant's sole cost and expense,
remove all or any portion of any Alterations which Landlord shall have
designated for removal at the time of expiration or earlier termination of the
Lease. Following any such removal of any of the Alterations, Tenant, at its sole
cost and expense, shall repair and restore the Premises to their original
condition.

                  Section 8.2       NOTICES. Tenant shall give Landlord at least
fifteen (15) days prior written notice of commencement of any work of
construction, alteration, addition, improvement, maintenance, repair or
replacement in the Premises in order to enable Landlord to post and/or record
such notices as Landlord deems necessary to protect the Premises, the Building,
the Project or Landlord from mechanics' liens, materialmen's liens or any other
liens. Tenant shall keep the Premises, the Common Area, the Building and the
Project free from any mechanics' liens, materialmen's liens or other liens
arising out of any labor or material furnished to Tenant or claimed to have been
furnished to Tenant or to Tenant's agents or contractors in connection with work
of any character performed or claimed to have been performed on the Premises by
or at the direction of Tenant, and promptly upon completion of any construction.
Tenant shall furnish to Landlord copies of unconditional lien waivers from all
contractors, subcontractors and suppliers involved in such construction.

                  Section 8.3       LABOR, OTHER RELATIONS. In the event that
Landlord shall determine that any work of construction, alteration, addition,
improvement, maintenance, repair or replacement in the Premises by Tenant shall
interfere with the labor relations in existence in the Building or the Project,
all such work shall be halted immediately by Tenant until such time as
construction can proceed without any such interference. Tenant shall cause any
work of construction, alteration, addition, improvement, maintenance, repair or
replacement by Tenant in the Premises to be conducted in such manner and at such
times so that any such work shall not disrupt or interfere with the use or
occupancy of other tenants or occupants of the Building or the Project.

                  Section 8.4       CONSTRUCTION INDEMNITY. Tenant shall
indemnify, defend and hold Landlord harmless from and against any and all
losses, costs, claims, damages, liabilities or causes of action (including
attorneys' fees) arising out of or in any way connected with Tenant's
performance of any work of construction, alteration, addition, improvement,
maintenance, repair or replacement in the Premises, or claims for work or labor
performed, or materials or supplies furnished, to or at the request of Tenant or
in connection with performance of any work done for the account of Tenant in the
Premises, the Common Area, the Building or the Project, whether or not Tenant
obtained


                                      16
<PAGE>

Landlord's permission to have such work done, labor performed, or materials or
supplies furnished.

                  Section 8.5        LANDLORD ALTERATIONS. Landlord shall have
the right to make changes or alterations to any portion of the Common Area, the
Building or the Project (which may include, without limitation, repair or
replacement of the Building's exterior facade, exterior window glass, elevators,
electrical systems. HVAC system, plumbing system, hallways, common restrooms or
lobbies but excluding the interior of the Premises, without Tenant's prior
written consent, which shall not be unreasonably withheld). Landlord shall not
be subject to any liability, and Tenant shall not be entitled to any
compensation or any diminution or abatement of rent, as a result of any noise,
dust, vibration or other disturbance to Tenant's use or occupancy of the
Premises arising out of the making of such changes or alterations. In no event
shall such changes or alterations be deemed to be a constructive or actual
eviction of Tenant, or a breach of Landlord's covenant of quiet enjoyment.
Landlord shall use reasonable efforts (which shall not include any obligation to
employ labor at overtime rates) to minimize disruption of Tenant's business
during the making of any such changes or alterations.

                               ARTICLE 9 - REPAIRS

                  Section 9.1       TENANT'S OBLIGATIONS. Subject to Section 9.2
below, Tenant, at Tenant's sole cost and expense, shall keep the Premises and
every part thereof in a clean and sanitary condition, and in good order,
condition and repair, ordinary wear and tear excepted. Except as expressly
provided herein, Landlord shall have no obligation whatsoever to alter, improve,
repair, maintain, remodel, decorate or paint the Premises or any part thereof.

                  Section 9.2        LANDLORD'S OBLIGATIONS. Except as otherwise
provided in Section 9.3 below, Landlord shall repair and maintain in good
condition and repair the following: (a) the structural elements of the Building
(including the foundation, floor slab, load-bearing and exterior walls, and
structural portions of the roof); (b) the Common area; and (c) all electrical,
plumbing, HVAC, sewage and other utility lines, equipment and systems installed
or furnished by Landlord, and located in or serving the Premises. Landlord shall
not be liable for any failure to make any such repairs or to perform any
maintenance unless such failure shall persist for an unreasonable time after
written notice of the necessity for such repairs or maintenance is given by
Tenant to Landlord. There shall be no diminution in or abatement of rent or
other amounts payable by Tenant under this Lease and no liability of Landlord by
reason of any injury to or interference with Tenant's business arising from
Landlord's performance of its repair and maintenance obligations under this
Lease. Tenant hereby waives any right to make repairs at Landlord's expense
under the provisions of Sections 1932, 194l and 1942 of the California Civil
Code or any other, similar statute, ordinance, rule or regulation now or
hereafter in effect.


                                      17
<PAGE>

                  Section 10.3      LANDLORD'S CONSENT. Landlord shall be
entitled to consider any reasonable factor in determining whether or not to
consent to a proposed assignment or sublease. Without limiting any other
circumstances in which it may reasonable for Landlord to withhold its consent to
a proposed assignment or sublease, Tenant acknowledges and agrees that it shall
be reasonable for Landlord to withhold its consent to any proposed assignment or
sublease if any of the following conditions shall not be satisfied:

                  (a)      The financial condition of the proposed assignee or
sublessee shall be equal to or greater than Tenant's financial condition as of
the date hereof and shall satisfy Landlord's then-current credit standards for
tenants of the Building or Project, and the proposed assignee or sublessee shall
otherwise have the financial capacity to perform all obligations under this
Lease to be performed by Tenant;

                  (b)      The proposed use of the Premises by the proposed
assignee or sublessee shall (i) comply with the provisions of Article 6 hereof,
(ii) be consistent with the general character of businesses carried on by
tenants of a first-class office building, (iii) not increase the likelihood of
damage or destruction to the Premises, the Building, or the Project, (iv) not
increase the density or occupancy of the Premises, (v) not be likely to cause an
increase in the insurance premiums for insurance policies carried by Landlord
with respect to the Building or Project, or (vi) not otherwise adversely impact
the Premises, the Building, the Project or Landlord's interest therein; or

                  (c)      Any  mortgagee or  beneficiary  under a deed of trust
whose consent to the assignment or sublease is required shall consent thereto.

                  Section 10.4      CONDITIONS. If Landlord consents to such
assignment or sublease in writing, Tenant shall be entitled to assign or
sublease the Subject Space to the proposed assignee or sublessee subject to the
following conditions:

                  (a)      As of the Transfer  Date,  Landlord  shall not have
the right to terminate this Lease because Tenant is in default under this Lease;

                  (b)      The  assignment or sublease  shall be on the same
terms and conditions set forth in the Transfer Notice given to Landlord;

                  (c)      No assignment or sublease shall be valid and no
assignee or sublessee shall take possession of the Premises or any portion
thereof until an executed counterpart of the assignment or sublease has been
delivered to Landlord;

                  (d)      No sublessee shall have a right further to sublease;

                  (e)      Any  proposed sublease would not result in more than
two subleases of portions of the Premises being in effect at any one time during
the Term;

                                      20
<PAGE>

                  (f)      Any assignee shall have assumed in writing the
obligations of Tenant under this Lease;

                  (g)      Any subtenant shall have agreed in writing to comply
with all terms and provisions of this Lease applicable to the Subject Space
except rent which shall be in the amount provided for in the sublease; and

                  (h)      Fifty percent (50%) of any sums or other economic
consideration received by Tenant as a result of such assignment or subletting
(less reasonable, BONA FIDE finders' fees or leasing commissions payable to a
third party in connection with such assignment or subletting, and less
reasonable attorneys' fees and costs paid in connection with such assignment or
sublease) whether denominated rent or otherwise, which exceed, in the aggregate,
the Monthly Base Rent and additional rent which Tenant is obligated to pay
Landlord under this Lease (prorated as to any sublease to reflect obligations
allocable to that portion of the Premises subject to such sublease) shall be
payable to Landlord as additional rent under this Lease, without affecting or
reducing any other obligation of Tenant hereunder. At Landlord's request, Tenant
shall deliver to Landlord such evidence of the sums or other economic
consideration received by Tenant as a result of assignment or sublease, and the
amounts deducted therefrom for proposes of calculating Landlord's share of such
sums or other economic consideration, as Landlord shall require from time to
time.

                  Section 10.5. LIMITATION ON REMEDIES. Tenant shall have no
right to, and Tenant hereby waives any right to assert a claim for, money
damages based upon any claim or assertion by Tenant that Landlord has
unreasonably withheld or delayed its consent to a proposed assignment or
sublease. Tenant's sole remedy shall be an action or proceeding for specific
performance, injunction or declaratory relief. Tenant acknowledges that Tenant's
rights under this Article 10 satisfy the conditions set forth in Section 1951.4
of the California Civil Code with respect to the availability to Landlord of
certain remedies for a default by Tenant under this Lease.

                  Section 10.6. CONTINUING LIABILITY OF TENANT. Regardless of
Landlord's consent, no subletting or assignment shall release Tenant from any of
its obligations hereunder or alter, impair or diminish the primary liability of
Tenant to pay the rent and to perform all other obligations to be performed by
Tenant hereunder. The acceptance of rent by Landlord from any other person shall
not be deemed to be a waiver by Landlord of any provision hereof. Consent to one
assignment or subletting shall not be deemed consent to any subsequent
assignment or subletting. If any assignee of Tenant or any successor of Tenant
defaults in the performance of any of the terms hereof, Landlord may proceed
directly against Tenant without the necessity of exhausting remedies against
such assignee or successor. Landlord may consent to subsequent assignments or
subleases or amendments or modifications to this Lease with assignees of Tenant,
without notifying Tenant, or any successor of Tenant, and without obtaining its
or their consent thereto, and

                                      21
<PAGE>


no such action by Landlord shall relieve Tenant from its liability under this
Lease. If Tenant assigns this Lease, or subleases all or a portion of the
Premises, or requests the consent of Landlord to any assignment or sublease,
then Tenant shall pay Landlord's reasonable attorneys' fees incurred in
connection therewith, but in no event in excess of $1,500 for each such
assignment or sublease during the initial Term of this Lease and in excess of
$2,000 for each such assignment or sublease during the Option Term (as defined
below).

                  Section 10.7. BANKRUPTCY.

                  (a)      If a petition is filed by or against Tenant for
relief under Title 11 of the United States Code, as amended ("Bankruptcy Code"),
and Tenant (including for purposes of this Section Tenant's successor in
bankruptcy, whether a trustee or Tenant as debtor-in-possession) assumes and
proposes to assign, or proposes to assume and assign, this Lease pursuant to the
provisions of the Bankruptcy Code to any person or entity who has made or
accepted a bona fide offer to accept an assignment of this Lease on terms
acceptable to Tenant, then notice of the proposed assignment setting forth (i)
the name and address of the proposed assignee, (ii) all of the terms and
conditions of the offer and proposed assignment, and (iii) the adequate
assurance to be furnished by the proposed assignee of its future performance
under the Lease, shall be given to Landlord by Tenant no later than twenty (20)
days after Tenant has made or received such offer, but in no event later than
ten (10) days prior to the date on which Tenant applies to a court of competent
jurisdiction for authority and approval to enter into the proposed assignment.
Landlord shall have the prior right and option, to be exercised by notice to
Tenant given at any time prior to the date on which the court order authorizing
such assignment becomes final and non-appealable, to receive an assignment of
this Lease upon the same terms and conditions, and for the same consideration,
if any, as the proposed assignee, less any brokerage commissions which may
otherwise be payable out of the consideration to be paid by the proposed
assignee for the assignment of this Lease.

                  (b)      If this Lease is assigned pursuant to the provisions
of the Bankruptcy Code. Landlord: (i) may require from the assignee a deposit or
other security for the performance of its obligations under the Lease in an
amount substantially the same as would have been required by Landlord upon the
initial leasing to a tenant similar to the assignee; and (ii) shall receive, as
additional rent, the sums and economic consideration described in Sections
365(b)(1) and (3) of the Bankruptcy Code. Any person or entity to which this
Lease is assigned pursuant to the provisions of the Bankruptcy Code shall be
deemed, without further act or documentation, to have assumed all of the
Tenant's obligations arising under this Lease on and after the date of such
assignment. Any such assignee shall, upon demand, execute and deliver to
Landlord an instrument confirming such assumption. No provision of this Lease
shall be deemed a waiver of Landlord's rights or remedies under the Bankruptcy
Code to oppose any assumption and/or assignment of this Lease, to require a
timely performance of Tenant's obligations under


                                      22
<PAGE>

this Lease, or to regain possession of the Premises if this Lease has neither
been assumed nor rejected within sixty (60) days after the date of the order for
relief or within such additional time as a court of competent jurisdiction may
have fixed. Notwithstanding anything in this Lease to the contrary, all amounts
payable by Tenant to or on behalf of Landlord under this Lease, whether or not
expressly denominated as rent, shall constitute rent for the purposes of Section
502(b)(6) of the Bankruptcy Code.

                       ARTICLE 11 - DESTRUCTION OR DAMAGE

                  Section 11.1. GENERAL. For the purposes of this Lease, the
term "Insured Casualty" shall mean damage to or destruction of the Premises, the
Building and/or the Project from a cause actually insured against, for which the
insurance proceeds paid or made available to Landlord are sufficient to rebuild
or restore the Premises, the Building and/or the Project, as applicable, under
then-existing applicable law to the condition existing immediately prior to the
damage or destruction, and "Uninsured Casualty" shall mean damage to or
destruction of the Premises, the Building and/or the Project from a cause not
actually insured against, or from a cause actually insured against but for which
the insurance proceeds paid or made available to Landlord are for any reason
insufficient to rebuild or restore the Premises, the Building and/or the
Project, as applicable, under then-existing applicable law to the condition
existing immediately prior to the damage or destruction.

                  Section 11.2. INSURED CASUALTY.

                  (a)      In the event of an Insured Casualty where the extent
of damage or destruction is less than twenty-five percent (25%) of the then full
replacement cost of the Premises, or is less than ten percent (10%) of the then
full replacement cost of the Building and/or the Project, as applicable.
Landlord shall rebuild or restore the Premises substantially to the condition
existing immediately prior to the damage or destruction (provided the damage or
destruction was not the result of the negligence or willful misconduct of
Tenant, its agents, employees, contractors or invitees), and provided that
then-existing applicable law would not prevent or otherwise interfere with
Landlord's ability so to rebuild or restore.

                  (b)      In the event of an Insured Casualty where the extent
of damage or destruction is equal to or greater than twenty-five percent (25%)
of the then full replacement cost of the Premises, or is equal to or greater
than ten percent (10%) of the then full replacement cost of the Building and/or
the Project, as applicable, Landlord shall have the right to rebuild or restore
the Premises substantially to the condition existing immediately prior to the
damage or destruction, or shall have the right to terminate this Lease. Landlord
shall notify Tenant in writing within sixty (60) days following the event of
damage or destruction of Landlord's election either to rebuild or restore the
Premises or to terminate this Lease.


                                      23
<PAGE>

                  Section 11.3. UNINSURED CASUALTY. In the event of an
Uninsured Casualty, Landlord shall have the right to (a) rebuild or restore the
Premises as soon as reasonably possible at Landlord's expense (unless the damage
or destruction was caused by the negligence or willful misconduct of Tenant, its
employees, agents, contractors or invitees, in which event Tenant shall pay all
costs of rebuilding or restoration), and this Lease shall continue in full force
and effect, or (b) terminate this Lease, in which event Landlord shall give
written notice to Tenant within sixty (60) days following the event of damage or
destruction of Landlord's election to terminate this Lease as of the date of the
event of damage or destruction, and if the damage or destruction was caused by
the negligence or willful misconduct of Tenant, its employees, agents,
contractors or invitees, Tenant shall be liable therefor to Landlord.

                  Section 11.4. TENANT'S ELECTION. Notwithstanding anything to
the contrary contained in this Article 11, Tenant may elect to terminate this
Lease in the event the Premises are damaged or destroyed and, in the reasonable
opinion of Landlord's architect or construction consultant, the repair or
restoration of the Premises cannot be substantially completed within three
hundred sixty (360) days, or cannot be commenced within one hundred eighty (180)
days following the event of damage or destruction. Tenant's election shall be
made by written notice to Landlord given within ten (10) days following Tenant's
receipt from Landlord of the estimate of the time required to complete the
repair or restoration of the Premises which Landlord shall deliver within thirty
(30) days after the occurrence of the event of damage or destruction. If Tenant
does not deliver such notice within such ten-day period, Tenant may not later
terminate this Lease even if substantial completion of the rebuilding or
restoration occurs subsequent to such 360-day period, provided that Landlord is
proceeding with diligence to rebuild or restore the Premises and has commenced
such rebuilding and restoration within the 180-day period provided for above. If
Tenant delivers such notice within such ten-day period, this Lease shall
terminate as of the date of occurrence of the event of damage or destruction.

                  Section 11.5. END OF TERM. Notwithstanding anything to the
contrary contained in this Article 11, in the event that the Premises, the
Building and/or the Project are damaged or destroyed in whole or in part from
any cause during the last twelve (12) months of the Term, Landlord, at
Landlord's option, may terminate this Lease as of the date of the event of
damage or destruction by giving written notice to Tenant of Landlord's election
to do so within thirty (30) days following the event of such damage or
destruction. If Tenant has been granted an option to extend or renew the Term
pursuant to any other provision of this Lease, then, unless otherwise permitted
herein, Landlord shall not be entitled to terminate this Lease by reason of such
damage or destruction during the last twelve (12) months of the Term if Tenant
exercises its option to extend or renew in accordance with this Lease within
twenty (20) days following the date of occurrence of the event of damage or
destruction.


                                      24
<PAGE>

                  Section 11.6. ABATEMENT OF RENTALS. If Landlord is required or
elects to rebuild or restore the Premises pursuant to this Article 11, the
then-current Monthly Base Rent, Excess Taxes and Excess Insurance Costs shall be
proportionately reduced during the period of repair or restoration, based upon
the extent to which the damage or making of repairs interferes with Tenant's
business conducted in the Premises, as reasonably determined by Landlord, but
only to the extent of any rental loss insurance proceeds received by Landlord
with respect to such damage or destruction to the Premises. All other
obligations of Tenant under this Lease shall continue unaffected.

                  Section 11.7. LIABILITY FOR PERSONAL PROPERTY. In no event
shall Landlord have any liability for, nor shall Landlord be required to repair
or restore, any injury or damage to any Alterations made by Tenant, trade
fixtures, equipment, merchandise, furniture or any other property installed by
Tenant or at the expense of Tenant. If Landlord or Tenant do not elect to
terminate this Lease pursuant to this Article 11, Tenant shall promptly rebuild
or restore all such property to the condition existing immediately prior to the
event of damage or destruction.

                  Section 11.8. WAIVER OF CERTAIN REMEDIES. Landlord and Tenant
acknowledge that the rights and obligations of the parties in the event of the
damage or destruction of the Premises are as set forth in this Article 11.
Tenant hereby expressly waives any rights to terminate this Lease upon damage or
destruction of the Premises, except as specifically provided by this Lease,
including, without limitation, any rights pursuant to the provisions of Sections
1932(2) and 1933(4) of the California Civil Code, as amended, or any other,
similar provisions of law.

                           ARTICLE 12 - EMINENT DOMAIN

                  Section 12.1. TAKING OF PREMISES. If all or any portion of the
Premises shall be taken by any public or quasi-public authority as a result of
the exercise of the power of eminent domain (which shall include a voluntary
sale or transfer by Landlord of all or any portion of the Premises under threat
of condemnation), this Lease shall terminate as to the part so taken as of the
date of taking, and, in the case of a partial taking which, in the reasonable
judgment of Tenant, materially impairs Tenant's ability to conduct its business
on the remainder of the Premises, Tenant shall have the right to terminate this
Lease as to the remainder of the Premises by written notice given to Landlord
within thirty (30) days after the date of such taking. If a material portion of
the Building or the Project is taken or if substantial alteration or
reconstruction of the Premises, the Building and/or the Project will, in
Landlord's reasonable judgment, be necessary or desirable as a result of such
condemnation or taking, Landlord may terminate this Lease by written notice
given to Tenant within thirty (30) days after the date of such taking.

                  Section 12.2. TEMPORARY TAKING. If all of the Premises shall
be temporarily condemned or taken for governmental occupancy for a period of
more than


                                      25
<PAGE>

one (1) year, this Lease shall terminate as of the date of taking, and Landlord
shall be entitled to any and all compensation, damages, income, rent and awards
in connection therewith. In the event of a temporary taking for a period of one
(1) year or less, this Lease shall remain in full force and effect, and all
compensation awarded as a result of such taking during the term of this Lease
(regardless of whether such temporary taking lasts for less or more than one (1)
year) shall be payable to Tenant.

                  Section 12.3. ABATEMENT OF RENT. If any portion of the
Premises shall be taken in eminent domain and this Lease shall not be terminated
as provided in this Article 12, as of the date of the taking, the Monthly Base
Rent, the Excess Taxes and Excess Insurance Costs shall be reduced in the same
proportion that the rentable area of that portion of the Premises so taken bears
to the original rentable area of the Premises.

                  Section 12.4. CONDEMNATION AWARD. Except as otherwise provided
in Section 12.2 above, in the event of any taking, Landlord shall be entitled to
any and all compensation, damages, income, rent, awards, and any interest
therein whatsoever which may be paid or made in connection therewith; provided,
however, that Tenant may make a separate petition, if such a separate petition
is permitted, for the cost of its moving expenses and the value of its personal
property (whether or not affixed to the Premises). In no event shall Tenant be
entitled to receive any award for any "bonus value" of this Lease or otherwise
attributable to the value of Tenant's interest under this Lease or in or to the
Premises. Each party hereby waives the provisions of California Code of Civil
Procedure Sections 1265.120 and 1265.130 allowing either party to petition the
Superior Court to terminate this Lease in the event of a partial taking of the
Premises.

                             ARTICLE 13 - INSURANCE

                  Section 13.1. LIABILITY INSURANCE. Tenant, at its sole cost
and expense, shall procure and maintain in full force and effect throughout the
Term (a) a policy of commercial general liability insurance in the minimum
amount of not less than Five Million Dollars ($5,000,000.00) combined annual
aggregate limits for bodily injury and property damage (with no lower per
occurrence limits), including contractual liability and personal injury
coverage, insuring Tenant against any liability arising out of or in connection
with Tenant's use, occupancy and/or maintenance of the Premises, the Building or
the Project, or arising out of this Lease, and (b) commercial automobile
insurance in the minimum amount of Two Million Dollars ($2,000,000) combined
single limit coveting all owned, non-owned or leased vehicles on or about the
Premises and Project. Such commercial general liability insurance shall name
Landlord, Landlord's mortgagee (of whom Tenant has been notified), if any, and
Landlord's property manager (of whom Tenant has been notified), if any, as
additional insureds, shall specifically include the liability assumed hereunder
by Tenant (provided, however, that the amount of such insurance shall not be
construed to limit the liability of Tenant hereunder), and shall provide that it
is primary insurance and not "excess over" or contributory with any other


                                      26
<PAGE>

insurance in force for or on behalf of Landlord. The policy shall eliminate
cross-liability and shall contain a severability of interest clause. Landlord
shall have the right, periodically during the Term, but not more frequently than
once each twelve (12) months, to require that Tenant increase the minimum
liability limits specified in this Section to an amount equal to the
then-prevailing minimum liability limits required by prudent landlords of
comparable office buildings in Menlo Park/Palo Alto, California area, as
determined by Landlord in its reasonable judgment.

                  Section 13.2. TENANT'S PROPERTY INSURANCE. Tenant, at its sole
cost and expense, shall procure and maintain in full force and effect throughout
the Term a policy of "all risk" property insurance, with theft, vandalism and
malicious mischief endorsements, covering any Alterations and Tenant's trade
fixtures, equipment, fixtures, furnishings and other personal property located
in or on the Premises, to the extent of at least full replacement cost thereof,
without any deduction for depreciation, and with a stated value endorsement
specifying an amount not less than the actual replacement cost thereof. Such
property insurance shall include "loss of rents" coverage sufficient to cover
Tenant's obligation to pay Monthly Base Rental and other amount payable under
this Lease for a twelve (12) month period. In the event that Tenant shall suffer
an insurable loss under such policy, the proceeds from any such policy shall be
used by Tenant for the replacement or restoration of such Alterations, trade
fixtures, equipment, inventory, fixtures, furnishings and personal property.

                  Section 13.3. TENANT'S ADDITIONAL INSURANCE. Tenant, at its
sole cost and expense, shall also procure and maintain in full force and effect
throughout the Term such additional insurance with such forms of coverage and in
such amounts as Landlord shall reasonably require, including, without
limitation, workers' compensation and employers' liability coverage as required
by law.

                  Section 13.4. INSURANCE CRITERIA. All insurance required to be
maintained by Tenant under this Lease shall (a) be issued by insurance companies
authorized to do business in the State of California (or if not so authorized,
reasonably approved by Landlord in writing) with a financial rating of at least
a A-VIII or better as rated in the most recent edition of "Best's Insurance
Guide"; (b) be issued as a primary policy; and (c) contain an endorsement
requiring not less than thirty (30) days' written notice from the insurance
company to Landlord and to Landlord's mortgagee before cancellation of any such
policy, except in the case of nonpayment, in which event such policy may be
cancelled upon ten (10) days' prior written notice.

                  Section 13.5. EVIDENCE OF COVERAGE. Tenant shall deposit
with Landlord, at the commencement of the Term, and on renewal of each policy
not less than twenty (20) days prior to expiration of such policy, a certified
copy of each insurance policy required to be carried by Tenant hereunder, or a
certificate of insurance as to such policy, together with evidence of payment of
premiums.


                                      27
<PAGE>

                  Section 13.6. WAIVER OF SUBROGATION. Landlord and Tenant each
hereby waives any and all rights of recovery against the other party for loss of
or damage to such waiving party or its property, where such loss or damage is
insured against under any insurance policy in force at the time of such loss or
damage. To the extent that such insurance endorsement is available at no or
nominal additional premium charge and does not adversely affect the ability of
such party to obtain such insurance, Landlord and Tenant each agree to obtain
for the benefit of the other party in the insurance policies carried by the
first party a waiver of any right of subrogation which any insurer of the party
may acquire.

                         ARTICLE 14 - WAIVER; INDEMNITY

                  Section 14.1. WAIVER OF LIABILITY. Landlord shall not be
liable for, and Tenant hereby waives all claims against Landlord with respect
to, any death or injury of any nature whatsoever that may be suffered or
sustained by Tenant or any employee, licensee, invitee, guest, agent or customer
of Tenant or any other person, from any causes whatsoever; or for any loss or
damage or injury to any property outside or within the Premises belonging to
Tenant or its employees, agents, customers, licensees, invitees, guests or any
other person, except to the extent that, in either event, such injury or damage
is caused by the gross negligence or willful misconduct of Landlord, its
employees or agents. Without limiting the generality of the waiver of liability
contained in this Section, Landlord shall not be liable for any damage of any
nature whatsoever to persons or property caused by explosion, fire or theft; by
breakage of any sprinkler, drainage or plumbing systems; by failure for any
cause to supply adequate drainage; by the interruption of any utility or other
service; by steam, gas, water, rain or other substances leaking, issuing or
flowing into any part of the Premises; by acts of God or the elements, acts of
public enemy, riot, strike, insurrection, war, court order, requisition or order
of governmental body or authority; by repair, maintenance or alteration of any
part of the Building or the Project (including any repair, maintenance or work
of construction performed by Tenant), or by anything done or omitted to be done
by any tenant, occupant or person in the Building or the Project, except to the
extent that any of the foregoing shall be caused by the gross negligence or
willful misconduct of Landlord, its employees or agents. Notwithstanding the
foregoing, in no event shall Landlord be liable or responsible in any way for
any loss of business by Tenant, lost profits of Tenant or any other
consequential damages of Tenant or its employees, agents, customers, licensees,
invitees, guests or any other person, regardless of the cause therefor.

                  Section 14.2. TENANT'S INDEMNITY. Tenant shall indemnify,
defend and hold Landlord, its employees, agents and contractors, harmless from
and against any and all losses, costs, claims, damages, liabilities or causes of
action (including attorneys' fees) arising out of or in any way connected with:
(a) Tenant's use or occupancy of the Premises or the conduct of Tenant's
business thereon, or any activity, work or other thing done, permitted or
suffered by Tenant in or about the Premises, the Building or the


                                      28
<PAGE>

Project, except to the extent caused by the gross negligence or willful
misconduct of Landlord, its employees or agents; (b) any damage to any property,
or injury, illness or death of any person occurring in, on, or about the
Premises, or any part thereof, arising at any time and from any cause
whatsoever, except to the extent caused by the gross negligence or willful
misconduct of Landlord, its employees or agents; (c) any damage to any property
or injury, illness or death of any person occurring in, on, or about any part of
the Building or the Project other than the Premises, to the extent such damage,
injury, illness or death shall be caused in whole or in part by the negligence
or willful misconduct of Tenant, its agents, employees, invitees, licensees or
customers; and (d) arising out of Tenant's breach of the provisions of this
Lease. The provisions of this Section shall survive the termination of this
Lease.

                              ARTICLE 15 - DEFAULT

                  Section 15.1. EVENTS OF DEFAULT. In addition to any other
event specified in this Lease as an event of default, the occurrence of any one
or more of the following events shall constitute a default under this Lease by
Tenant:

                  (a)      Tenant's failure to pay when due any Monthly Base
Rent, Excess Taxes. Excess Insurance Costs, Excess Utility Charges or any other
amounts that Tenant is obligated to pay to Landlord pursuant to this Lease;
provided, however, on not more than one occasion in any twelve (12) consecutive
month period throughout the Term, Tenant's failure to pay rent when due shall
not constitute an Event of Default unless such failure shall continue for five
(5) days following written notice thereof from Landlord;

                  (b)      Tenant's failure to perform any other covenant,
agreement or obligation of Tenant contained in this Lease within thirty (30)
days following Landlord's written notice thereof to Tenant;

                  (c)      Tenant's abandonment of the Premises, or Tenant's
vacation of the Premises without providing adequate security for the Premises;

                  (d)      Tenant's making of any general assignment for the
benefit of creditors; or the commencement and continuation for at least thirty
(30) days of any case, action or proceeding by, against or concerning Tenant
under the Bankruptcy Code or any other federal or state bankruptcy, insolvency
or debtor's relief law or otherwise seeking Tenant's financial reorganization or
an arrangement with any of Tenant's creditors;

                  (e)      Appointment of receiver, trustee or other person to
take possession of substantially all of Tenant's assets;

                  (f)      Commencement of proceedings for winding up or
dissolving (whether voluntary or involuntary) Tenant, if Tenant is a
corporation, partnership or limited liability company;


                                      29
<PAGE>

                  (g)      Levy of a writ of attachment or execution on Tenant's
interest under this Lease, if such writ continues for a period of thirty (30)
days; and

                  (h)      Assignment of this Lease or any interest hereunder,
or sublease of all or any portion of this Premises, in violation of the
provisions of Article 10 of this Lease.

                  Section 15.2. LANDLORD'S REMEDIES. If a default by Tenant
under this Lease shall occur, in addition to any other rights and remedies
available to Landlord at law or in equity (including, without limitation, the
provisions of Section 1951.4 of the California Civil Code or any successor
statutory provision), Landlord at any time thereafter shall have the right to
give a written notice of termination of this Lease to Tenant, and on the date
specified in such notice (which shall be not less than three (3) days after the
giving of such notice), Tenant's right to possession of the Premises and this
Lease shall terminate, unless on or before such date all arrears of Monthly Base
Rent and all other sums payable by Tenant under this Lease and all costs and
expenses incurred by Landlord with respect to such default shall have been paid
by Tenant, and any other breaches of this Lease by Tenant at that time existing
shall have been fully remedied to the satisfaction of Landlord. If Landlord
shall terminate this Lease pursuant to the provisions of this Section, Landlord
shall have all the rights and remedies of a landlord provided by Section 1951.2
of the California Civil Code or any successor statutory provision. Upon such
termination, in addition to any other rights and remedies to which Landlord may
be entitled under applicable law, Landlord may recover from Tenant: (a) the
worth at the time of award of all unpaid rent which had been earned at the time
of termination; (b) the worth at the time of award of the amount by which all
unpaid rent which would have been earned after termination until the time of
award exceeds the amount of such rent loss that Tenant proves could have been
reasonably avoided; (c) the worth at the time of award of the amount by which
all unpaid rent for the balance of the term of this Lease after the time of
award exceeds the amount of such rent loss that Tenant proves could be
reasonably avoided; and (d) any other amount necessary to compensate Landlord
for all the detriment proximately caused by Tenant's failure to perform its
obligations under this Lease or which in the ordinary course of things would be
likely to result therefrom, including, without limitation, attorneys' fees and
costs; brokerage commissions; the cost of alterations, additions, improvements,
renovations, refurbishment and repair of the Premises; the cost of removal and
storage of Tenant's trade fixtures, equipment, fixtures, furnishings and other
personal property located in the Premises; and the unamortized portion, as of
the date of termination of this Lease, of any Tenant Improvements constructed or
installed by Landlord at its expense (as amortized over the Term with interest
thereon at the Interest Rate). The "worth at the time of award" of the amounts
referred to in clauses (a) and (b) above shall be computed by allowing interest
at the Interest Rate. The worth at the time of award of the amount referred to
in clause (c) above shall be computed by discounting such amount at a rate equal
to the discount rate of the Federal Reserve Bank of San Francisco at the time of
award plus one percent (1%).


                                   30
<PAGE>

                  Section 15.3. LATE CHARGES; INTEREST. Tenant acknowledges that
late payment by Tenant to Landlord of Monthly Base Rent, Excess Expenses, Excess
Taxes, Excess Insurance Costs, Excess Utility Charges or any other amounts
payable by Tenant to Landlord under this Lease will cause Landlord to incur
costs not contemplated by this Lease, the exact amount of such costs being
extremely difficult and impracticable to ascertain. Such costs include, without
limitation, processing and accounting charges, and late charges that may be
imposed on Landlord by the terms of any indebtedness secured by an encumbrance
covering the Premises. Therefore, if any such amount due from Tenant is not
received by Landlord within seven (7) days after the same shall become due and
payable, Tenant shall pay to Landlord on demand an additional sum equal to five
percent (5%) of the overdue amount as a late charge. The parties agree that this
late charge represents a fair and reasonable estimate of the costs that Landlord
will incur by reason of such late payment by Tenant. Acceptance of any late
charge shall not constitute a waiver of Tenant's default with respect to the
overdue amount, or prevent Landlord from exercising any of the other rights and
remedies available to Landlord. In addition, each installment of Monthly Base
Rent and any other amount payable by Tenant to Landlord under this Lease which
shall not have been paid within seven (7) days after the same shall have become
due and payable shall bear interest at the Interest Rate from the date that the
same became due and payable until paid, whether or not any demand shall be made
therefor.

                  Section 15.4. LEASE CONTINUES UNTIL TERMINATION. In the event
of a default by Tenant, this Lease shall continue in effect for so long as
Landlord shall not terminate Tenant's right to possession, and Landlord may
enforce all its rights and remedies under this Lease, including the right to
recover the rent as it becomes due under this Lease. Acts of maintenance or
preservation or efforts to relet the Premises or the appointment of a receiver
upon initiative of Landlord to protect Landlord's interest under this Lease
shall not constitute a termination of Tenant's right to possession.

                  Section 15.5. RELETTING PREMISES. In the event of a default by
Tenant, Landlord, at Landlord's election, may re-enter the Premises and, without
terminating this Lease, at any time and from time to time, relet the Premises or
any portion thereof for the account and in the name of Tenant. Landlord, at
Landlord's election, may eject Tenant or any of Tenant's assignees, sublessees
or any other person claiming any right in or through this Lease. Tenant shall
nevertheless pay to Landlord on the dates specified in this Lease all amounts
payable by Tenant to Landlord under this Lease, plus Landlord's costs and
expenses in connection therewith, less the proceeds of any sublease or
reletting. No act by or on behalf of Landlord under this Section shall
constitute a termination of this Lease unless Landlord gives Tenant written
notice of termination as provided in Section 15.2. Notwithstanding any prior
reletting without termination, Landlord may later elect to terminate this Lease
by reason of such default by Tenant.


                                   31
<PAGE>

                  Section 15.6. CURE BY LANDLORD. If Tenant shall fail to pay
any amount payable by Tenant to Landlord hereunder or shall fail to perform any
other covenant, agreement or obligation of Tenant hereunder and such failure
shall continue for thirty (30) days after notice thereof by Landlord, then
Landlord may, but shall not be obligated to, and without waiving or releasing
Tenant from any obligation, make any such payment or perform any such covenant,
agreement or obligation on Tenant's behalf. All sums so paid by Landlord and all
costs incurred by Landlord in taking such action shall be paid to Landlord on
demand, together with interest thereon at the Interest Rate until the date of
payment. In addition to all other rights and remedies of Landlord, Landlord
shall have the same rights and remedies in the event of the non-payment thereof
by Tenant as in the case of default by Tenant in the payment of rent.

                  Section 15.7. LANDLORD'S DEFAULT. In no event shall Landlord
be deemed to be in default under this Lease unless and until Landlord shall have
defaulted in the performance of its obligations under this Lease and Tenant
shall have given Landlord written notice of the default and, within a reasonable
period of time following Landlord's receipt of such notice, but in no event less
than thirty (30) days nor more than forty-five (45) days following Landlord's
receipt of such notice, Landlord shall not commence diligently to prosecute the
cure of such default to completion. In the event of any alleged default on the
part of Landlord under this Lease, Tenant shall give notice by registered mail
to any beneficiary or mortgagee under a deed of trust or mortgage encumbering
the Premises whose address shall have been furnished to Tenant, and shall offer
such beneficiary or mortgagee a reasonable opportunity to cure the default,
including time to obtain possession of the Premises by power of sale or judicial
foreclosure, if such shall be necessary to effect a cure.

                  Section 15.8      REMEDIES CUMULATIVE. The remedies provided
for in this Lease are in addition to any other remedies available to Landlord at
law or in equity by statute or otherwise.

                  Section 15.9.     SECURITY DEPOSIT.

                  (a)      Concurrently with Tenant's execution of this Lease,
Tenant shall deliver to Landlord an unconditional, irrevocable, transferable
letter of credit in the stated amount of Six Hundred Seventy-Six Thousand One
Hundred Dollars ($676,100) issued by a bank approved by Landlord in favor of
Landlord as beneficiary, for the term provided for below and otherwise in form
and substance satisfactory to Landlord ("Letter of Credit"). The Letter of
Credit shall be issued for an initial term of one year following the date of
this Lease, and Tenant shall cause the Letter of Credit to be renewed for
successive twelve-month periods throughout the Term not less than thirty (30)
days prior to each expiration date of the Letter of Credit, until Tenant shall
have the right to reduce the amount of the Letter of Credit as provided in
subparagraph (b) below. The Letter of Credit shall entitle Landlord to draw the
entire stated amount thereof upon presentation of


                                   32
<PAGE>

a sight draft in the amount of the draw. The Letter of Credit shall be held by
Landlord as security for the faithful performance by Tenant of all of the
covenants, agreements and obligations under this Lease to be performed by Tenant
during the Term. If Tenant shall fail to pay Monthly Base Rental or other
amounts payable by Tenant to Landlord under this Lease, or if Tenant shall
otherwise default with respect to any provision of this Lease after the
expiration of any applicable cure period, Landlord shall have the right, but
shall not be obligated, to draw the entire stated amount of the Letter of Credit
and to hold the proceeds thereof as a cash security deposit ("Security
Deposit"), and to use, apply or retain all or any portion of the Security
Deposit for the payment of rental or any other amount which Landlord may expend
or become obligated to expend by reason of Tenant's default, or to compensate
Landlord for any other loss or damage which Landlord may suffer by reason of
Tenant's default. If Landlord shall make any draw upon the Letter of Credit and
apply such draw to the cure of any default, Tenant shall, within ten (10) days
after Landlord's written demand therefor, deposit with Landlord a replacement,
additional or amended Letter or Letters of Credit in the same form (including
total stated amount and issuer) as the Letter of Credit drawn upon by Landlord.
If Landlord shall so use or apply any portion of any cash Security Deposit held
by Landlord. Tenant shall, within ten (10) days after Landlord's written demand
therefor, deposit cash with Landlord in the amount so used or applied by
Landlord. Landlord shall not be required to keep any Security Deposit separate
from Landlord's other funds, and Tenant shall not be entitled to any interest on
any Security Deposit. Landlord shall return the Letter of Credit, any Security
Deposit, and/or any balance thereof not applied in accordance with the
provisions of this Lease, to Tenant within thirty (30) days following the
expiration of this Lease and after Tenant has surrendered the Premises to
Landlord in the condition required under this Lease. In the event that Landlord
shall transfer its interest in the Premises, Landlord shall transfer the Letter
of Credit (to the extent transferable) and/or any funds then held by Landlord on
account of any cash Security Deposit to Landlord's transferee, and Landlord
shall thereupon be released from all liability to Tenant for return of the
Letter of Credit and/or cash Security Deposit.

                  (b)      If a default by Tenant under this Lease after the
expiration of any applicable cure period shall not have occurred at any time
prior to such time, effective not earlier than the first day of the fourth year
of the Term, Tenant shall have the right to cause the stated amount of the
Letter of Credit to be reduced to Three Hundred Forty-Two Thousand Two Hundred
Dollars ($338,100) by delivering to Landlord an amendment to the Letter of
Credit then held by Landlord acceptable to Landlord, or by delivering to
Landlord a new Letter of Credit in such lesser stated amount, but otherwise in
the same form as the Letter of Credit then held by Landlord. Such Letter of
Credit, and any amounts drawn thereunder, shall otherwise be held by Landlord on
all of the terms and provisions of subparagraph (a) above.


                                   33
<PAGE>

                           ARTICLE 16 - SUBORDINATION

                  Section 16.1. SUBORDINATION OF LEASE. This Lease shall be
subject and subordinate at all times to the lien of all mortgages and deeds of
trust in any amount or amounts whatsoever (including all advances thereunder,
renewals, replacement, modifications, supplements, and extensions thereof) now
or hereafter placed on or against the Premises, the Building or the Project, or
on or against Landlord's interest or estate therein, all without the necessity
of having further instruments executed on the part of Tenant to effectuate such
subordination. Tenant agrees to execute and deliver upon demand such further
instruments evidencing such subordination of this Lease to the lien of any such
mortgages or deeds of trust as may be required by Landlord, provided that each
mortgagee or beneficiary under any such mortgage or deed of trust, or purchaser
or grantee in respect thereof, shall agree, in a commercially reasonable
non-disturbance agreement, not to terminate or disturb Tenant's possession of
the Premises under this Lease in the event of termination of such ground or
underlying lease or foreclosure of such mortgage or deed of trust or deed in
lieu thereof, as the case may be, so long as Tenant is not in default under this
Lease beyond any applicable cure period under this Lease. In the event of the
foreclosure of any mortgage or deed of trust encumbering the Premises, the
Building or the Project, or on or against Landlord's estate or interest therein,
or in the event of a deed-in-lieu of foreclosure thereof, Tenant shall be bound
to any such mortgagee or beneficiary under any such mortgage or deed of trust,
or any other purchaser or grantee in foreclosure or under a deed-in-lieu
thereof, and Tenant hereby attorns to any such party as its landlord, such
attornment to be effective and self-operative without the execution of any
further instrument immediately upon such party's succeeding to Landlord's
interest under this Lease.

                  Section 16.2. SUBORDINATION OF DEED OF TRUST. Notwithstanding
anything to the contrary set forth above, any mortgagee or beneficiary under any
mortgage or deed of trust may at any time subordinate its mortgage or deed of
trust to this Lease in whole or in part, without Tenant's consent, by execution
of a written document subordinating such mortgage or deed of trust to this Lease
to the extent set forth in such document, and thereupon this Lease shall be
deemed prior to such mortgage or deed of trust to the extent set forth in such
document without regard to their respective dates of execution, delivery and/or
recording. In that event, to the extent set forth in such document, such
mortgage or deed of trust shall have the same rights with respect to this Lease
as would have existed if this Lease had been executed, and a memorandum thereof
recorded, prior to the execution, deliver and recording of the mortgage or deed
of trust.

                  Section 16.3. APPROVAL BY MORTGAGEES. Tenant hereby
acknowledges that the provisions of this Lease may be subject to the approval of
any lender that may hereafter make a loan secured by a mortgage or deed of trust
on the Premises, the Building or the Project. If such lender shall require, as a
condition to such financing, any modifications of this Lease in order to protect
the security of such mortgage or deed of


                                   34
<PAGE>

trust, at Landlord's request, Tenant agrees to execute appropriate amendments to
this Lease to effect such modifications; provided, however, that no such
modification shall change the size, location or dimension of the Premises or
increase the amount of the rent or other amounts payable by Tenant under this
Lease or otherwise materially, adversely affects any of Tenant's rights or
obligations under this Lease.

                         ARTICLE 17 - ENTRY BY LANDLORD

                  Landlord shall have the right to enter the Premises at
reasonable hours and after reasonable notice (except in the event of an
emergency in which event no notice shall be required) to: (a) inspect the
Premises; (b) exhibit the same to prospective purchasers, lenders or tenants;
(c) determine whether Tenant is complying with all of its obligations hereunder;
(d) provide any service to be provided by Landlord to Tenant hereunder; (e) post
notices of non-responsibility and "for sale" and "for lease" signs; and (f) make
repairs required of Landlord under the terms hereof or make repairs to any
adjoining space or make repairs, alterations or improvements to any other
portion of the Building or the Project. Tenant hereby waives any claim for
damages for any injury or inconvenience to or interference with Tenant's
business, any loss of occupancy or quiet enjoyment of the Premises, and any
other loss occasioned by such entry, provided that Landlord takes reasonable
steps to minimize the interference with Tenant's use and enjoyment of the
Premises. Landlord shall at all times have and retain a key with which to unlock
all of the doors in, on or about the Premises (excluding Tenant's vaults, safes
and similar areas agreed upon in writing by Tenant and Landlord prior to the
date of execution of this Lease by the parties). Landlord shall have the right
to use any and all means which Landlord may deem appropriate to open such doors
in an emergency in order to obtain entry to the Premises, and no entry to the
Premises obtained by Landlord by any of such means shall under any circumstance
be construed or deemed to be a forcible or unlawful entry into, or a detainer
of, the Premises or an eviction, actual or constructive, of Tenant from the
Premises, or any portion thereof.

                       ARTICLE 18 - OPTION TO EXTEND TERM

                  Section 18.1. OPTION. Subject to the provisions of Section
18.2 below, Landlord hereby grants to Tenant the option to extend the Term
hereof for one (1) additional five (5) year period ("Option Term") following
expiration of the initial Term specified in the Basic Lease Information
("Initial Term"), on all of the terms and conditions contained herein, except
that Monthly Base Rent shall be as provided below and that Tenant shall have no
further option to extend the Term. Tenant shall have the right to exercise the
such option by giving written notice of exercise of the option ("Option Notice")
to Landlord not less than twelve (12) months prior to the expiration of the
Initial Term. Notwithstanding the foregoing, if Tenant shall be in default under
this Lease beyond all applicable cure periods on the date of giving the Option
Notice, Tenant shall have no right to extend the Term and, at Landlord's option,
this Lease shall expire at the end of the Initial Term; and if Tenant shall be
in default under this Lease beyond all


                                   35
<PAGE>

applicable cure periods on the date the Option Term is to commence, the Option
Term shall not commence and, at Landlord's option, this Lease shall expire at
the end of the Initial Term. The Monthly Base Rent for the Option Term shall be
equal to the Fair Market Rental (as hereinafter defined) of the Premises at the
commencement of the Option Term. As used in this Lease, the word "Term" shall
mean the Term as the same may be extended pursuant to the provisions of this
Article 18, as applicable.

                  Section 18.2. LANDLORD'S USE. Notwithstanding the provisions
of Section 18.1 above, if Landlord or any affiliate of Landlord shall require
the use of the Premises at any time subsequent to the Initial Term for its own
occupancy, then Tenant shall not have the right to extend the Term of this Lease
for the Option Term, and the Term of this Lease shall expire at the end of the
Initial Term. If Landlord or any affiliate of Landlord shall so require the use
of the Premises, Landlord shall give to Tenant written notice of such fact not
later than fifteen (15) months prior to the end of the Initial Term.

                  Section 18.3. FAIR MARKET RENTAL.

                  (a)      "Fair Market Rental" shall mean the monthly full
service rental being charged for comparable space in comparable office buildings
in the Menlo Park/Palo Alto, California area as of the date of commencement of
the Option Term, with similar amenities, taking into consideration the size,
location, proposed term of the lease, extent of services to be provided, the
time that the particular rate under consideration became or is to become
effective, and other relevant factors; provided, however, that Monthly Base Rent
shall in no event be less than the Monthly Base Rent which was in effect
immediately prior to the date of commencement of the Option Term. Within thirty
(30) days following receipt of the Option Notice, Landlord shall give to Tenant
written notice of Landlord's estimation of Fair Market Rental. If Tenant shall
not agree with such estimation of Fair Market Rental, Landlord and Tenant shall
negotiate in good faith to agree upon the Fair Market Rental for a period of
forty-five (45) days following the date of Landlord's notice to Tenant. If
Landlord and Tenant shall be unable to agree upon the Fair Market Rental within
such period of time, Fair Market Rental shall be determined pursuant to the
arbitration procedure set forth in this Article 18. In the event that such
arbitration not have been concluded prior to the date of commencement of the
Option Term, Tenant shall continue to pay as Monthly Base Rent hereunder, until
the Fair Market Rental has been determined by arbitration, the Monthly Base Rent
payable with respect to the month immediately preceding the commencement of the
Option Term. After the Fair Market Rental has been determined by arbitration,
then any adjustment required to adjust the amount previously paid shall be made
by payment by Tenant to Landlord within ten (10) days after such determination
of Fair Market Rental

                  (b)      In the event that Landlord and Tenant shall be unable
to agree upon Fair Market Rental within the period of time specified in
subparagraph (a) above, within ten (10) days thereafter, each of the parties
shall select a commercial real estate broker


                                   36
<PAGE>

from a recognized real estate brokerage firm having offices in Palo Alto or San
Jose, California, who has at least five (5) years' full-time commercial real
estate brokerage experience and who is familiar with the Fair Market Rental of
commercial office space in comparable office buildings in Menlo Park/Palo Alto,
California area, and shall give written notice of such selection to the other
party specifying therein the name and address of the person to act as the
arbitrator on such party's behalf. If either party shall fail to notify the
other party of its appointment of a broker having such qualifications within or
by the time specified, then the broker appointed by the other party shall make
the sole determination of Fair Market Rental of the Premises, and such
determination shall be binding upon the parties.

                  (c)      The Fair Market Rental shall be determined by the two
brokers appointed by the parties in accordance with the following procedures.
Within thirty (30) days following the appointment of the brokers by the parties,
each of the brokers shall state in writing his determination of the Fair Market
Rental supported by the reasons therefor and shall provide copies to each party.
If such determinations do not differ by more than ten percent (10%), the Fair
Market Rental shall be the average of the two determinations. If such
determinations differ by more than ten percent (10%) and the two brokers are
subsequently unable to agree upon the Fair Market Rental, the two brokers shall
appoint a third broker, who shall be a competent and impartial person with
qualifications similar to those required of the first two brokers. If the two
brokers are unable to agree upon such appointment within ten (10) days following
their determinations of Fair Market Rental, then either Landlord or Tenant, on
behalf of both parties, may request appointment of such a qualified person by
the Presiding Judge of the San Mateo County Superior Court acting in his
individual capacity. Following appointment of the third broker, he shall
promptly make his determination of Fair Market Rental in the manner provided
above, and the average of the three determinations shall constitute the Fair
Market Rental. If, however, the low determination of Fair Market Rental and/or
the high determination of Fair Market Rental are more than ten percent (10%)
lower and/or higher than the middle determination, any such low determination
and/or high determination shall be disregarded. If only one determination is
more than ten percent (10%) above or below the middle determination, such that
only one determination needs to be disregarded, the remaining two determinations
shall be added together and their total divided by two; the resulting quotient
shall be the Fair Market Rental. If both the low determination and the high
determination are disregarded, then the middle determination shall establish the
Monthly Base Rent for the Premises for the Option Term and shall be final and
binding upon the parties.

                  (d)      In the event of a failure, refusal or inability of
any broker to act, his successor shall be appointed by him, but in the case of
the third broker, his successor shall be appointed in the same manner as that
set forth herein with respect to the appointment of the original third broker.
The brokers shall make the final determination of Fair Market Rental not later
than sixty (60) days prior to the commencement of the


                                   37
<PAGE>

Option Term. Each party shall pay the fees and expenses of its respective broker
and both shall pay one-half (1/2) of the fees and expenses of the third broker.
Attorneys' fees and expenses of counsel shall be paid by the respective party
engaging such counsel.

                           ARTICLE 19 - MISCELLANEOUS

                  Section 19.1. HOLDING OVER. If Tenant shall remain in
possession of the Premises after the expiration or earlier termination of this
Lease with the written consent of Landlord, such occupancy shall be a tenancy
from month-to-month and all of the terms, covenants and agreements hereof shall
otherwise continue to apply and bind Tenant so long as Tenant shall remain in
possession, except that the Monthly Base Rent shall be one hundred fifty percent
(150%) of the Monthly Base Rent payable for the last month of the Term, prorated
on a daily basis for each day that Tenant remains in possession. If Tenant shall
remain in possession of the Premises after the expiration or earlier termination
of this Lease without the written consent of Landlord, Tenant shall indemnify,
defend and hold Landlord harmless against any and all claims, losses and
liabilities for damages resulting from failure to surrender possession,
including, without limitation, any claims made by any succeeding tenant.

                  Section 19.2. LANDLORD'S INTEREST. The term "Landlord" as used
herein shall mean only the owner or owners at the times in question of fee title
to the Premises. In the event of a sale, conveyance or assignment by Landlord of
Landlord's interest in the Premises, the Building or the Project, Landlord shall
be relieved, from and after the date of such sale, conveyance or assignment, of
any liability thereafter accruing upon any of the agreements, obligations or
covenants of Landlord under the Lease, and for such future period Tenant agrees
to look solely to the successor-in-interest of Landlord in and to this Lease,
provided that any funds in the hands of Landlord, in which Tenant has an
interest, shall be delivered to such successor-in-interest. This Lease shall not
be affected by any such sale, conveyance, or assignment, however, and Tenant
agrees to attorn to the purchaser or assignee, such attornment to be effective
and self-operative without the execution of any further instruments on the part
of any of the parties to this Lease.

                  Section 19.3. QUIET ENJOYMENT. Landlord hereby covenants in
favor of Tenant that, provided that Tenant shall pay all rent and perform all
other covenants, agreements and obligations of Tenant under this Lease, Tenant
shall have and enjoy quiet possession of the Premises throughout the Term
without any hindrance or interruption by Landlord or any person lawfully
claiming by, through or under Landlord, subject to the terms and conditions of
this Lease and any mortgage or deed of trust to which this Lease is subject and
subordinate.

                  Section 19.4. LANDLORD'S LIABILITY. The liability of Landlord
under this Lease or otherwise in connection with the Premises or the Building
shall be limited to Landlord's interest in the Project, and in no event shall
any other assets of Landlord or


                                   38
<PAGE>

any assets of any constituent partner or member of Landlord be subject to any
liability arising out of or in connection with this Lease, the Premises, the
Building or the Project.

                  Section 19.5. NO 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, either terminate any or all existing
subleases or operate as an assignment to Landlord of any or all of such
subleases.

                  Section 19.6. SURRENDER OF PREMISES. At the expiration of the
Term or upon earlier termination of this Lease, Tenant shall surrender to
Landlord possession of the Premises, in the same condition as received,
reasonable wear and tear excepted. Tenant shall have the right to remove from
the Premises any of Tenant's movable partitions, trade fixtures, furnishings,
fixtures or equipment which may be removed without causing damage to the
Premises, and shall remove any Alterations and any other alterations, additions
or improvements, trade fixtures, equipment or furnishings which Landlord shall
have directed to be removed, and shall promptly repair any damage to the
Premises caused by such removal. Any personal property of Tenant not removed
from the Premises shall, to the extent permitted by law, be deemed to have been
abandoned by Tenant and shall thereupon become the property of Landlord.

                  Section 19.7. ESTOPPEL CERTIFICATE. At any time and from time
to time, but in no event later than ten (10) days' following a request therefor
by Landlord, Tenant shall execute, acknowledge and deliver to Landlord, a
certificate certifying: (a) that Tenant has accepted the Premises (or, if Tenant
has not done so, that Tenant has not accepted the Premises, and specifying the
reasons therefor); (b) the commencement and expiration dates of this Lease; (c)
whether there are then existing any defaults by Tenant or Landlord in the
performance of its obligations under this Lease (and, if so, specifying the
same); (d) that this Lease is unmodified and in full force and effect (or, if
there have been modifications, that this Lease is in full force and effect, as
modified, and stating the date and nature of each modification); (e) the
capacity of the person executing such certificate, and that such person is duly
authorized to execute the same on behalf of Tenant; (f) the date, if any, to
which rent and other sums payable hereunder have been paid; (g) that no notice
has been received by Tenant of any default which has not been cured, except as
to defaults specified in the certificate; (h) the amount of any security deposit
and prepaid rent; and (i) such other matters as Landlord may request. Any such
certificate may be relied upon by any prospective purchaser of, or any existing
or prospective mortgagee or beneficiary under any deed of trust affecting, the
Building, the Project or any part thereof.

                  Section 19.8. NO LIGHT, AIR OR VIEW EASEMENT. Nothing
contained in this Lease shall grant to or confer upon Tenant any right to
receive any particular amount or level of light, air or view from the Premises.
Any diminution in or shutting off of light, air or view by any structure which
is now or may hereafter be erected in the Project


                                   39
<PAGE>

or on other lands adjacent to the Building shall in no way affect this Lease or
impose any liability upon Landlord. Noise, dust or vibration or other incidents
to new construction of improvements on lands adjacent to the Building, whether
or not owned by Landlord, shall in no way affect this Lease or impose any
liability on Landlord.

                  Section 19.9. NOTICES. All notices and other communications
which may or are required or permitted to be given by either party to the other
hereunder shall be in writing and shall be deemed to have been given upon
receipt or refusal of receipt, when personally delivered or transmitted by
private nationally recognized overnight courier service, or by deposit in the
United States mail, certified or registered, with return receipt requested,
postage prepaid, and addressed as follows: prior to the date on which Tenant
accepts possession of the Premises, at Tenant's address prior to occupancy set
out in the Basic Lease Information, and thereafter to Tenant at the Premises, or
to such other place as Tenant may from time to time designate in a written
notice to Landlord; to Landlord at the address specified in the Basic Lease
Information, or to such other place as Landlord may from time to time designate
in a written notice to Tenant.

                  Section 19.10. SUCCESSORS. Subject to the provisions of
Article 10 of this Lease, all of the terms, covenants and conditions contained
in this Lease shall be binding upon, and shall inure to the benefit of, the
heirs, executors, administrators, successors and assigns of the parties hereto.

                  Section 19.11. ATTORNEYS' FEES. In the event of any action or
proceeding brought by either party against the other under this Lease, the
prevailing party shall be entitled to recover court costs and the fees of its
attorneys in such action or proceeding (whether at the administrative, trial or
appellate levels) in such amount as the court or administrative body may award.

                  Section 19.12. WAIVER. The failure of Landlord or Tenant to
exercise their respective rights in connection with any breach by Tenant or
Landlord, as applicable, of any provision of this Lease shall not be deemed to
be a waiver of such provision or any subsequent breach or violation of the same
or any other provision of this Lease. The subsequent acceptance of rent
hereunder by Landlord shall not be deemed to be a waiver of any preceding breach
or violation by Tenant of any provision of this Lease other than the failure of
Tenant to pay the particular rent so accepted, regardless of Landlord's
knowledge of such preceding breach or violation at the time of acceptance of
such rent.

                  Section 19.13. CAPTIONS. The captions and headings of the
Articles and Sections in this Lease are for convenience only and shall not in
any way limit or be deemed to construe or interpret the terms and provisions of
this Lease.

                  Section  19.14.  TIME OF ESSENCE.  Time is of the essence of
this Lease and of all provisions hereof, except as otherwise provided herein.


                                   40

<PAGE>

                  Section 19.15. INTEREST RATE. As used herein, the term
"Interest Rate" shall mean a per annum rate of interest equal to three percent
(3%) plus the rate most recently announced by Wells Fargo Bank, N.A., at its
main office in San Francisco, California, as its "Prime Rate", serving as the
basis upon which effective rates of interest are calculated for those loans
making reference thereto, but in no event in excess of the maximum applicable
usury limitation.

                  Section  19.16.  GOVERNING  LAW. This Lease shall be governed
by, and construed and enforced in accordance with, the laws of the State of
California.

                  Section 19.17. ENTIRE AGREEMENT. The terms of this Lease are
intended by the parties as a final expression of their agreement with respect to
such terms as are included in this Lease and shall supersede any prior
agreements, memoranda or other written communications regarding this Lease. The
parties further intend that this Lease constitutes the complete and exclusive
statement of its terms and that no extrinsic evidence whatsoever may be
introduced in any judicial proceedings, if any, involving this Lease.

                  Section 19.18. INVALIDITY. If any provision of this Lease or
the application thereof to any person or circumstance shall, to any extent, be
invalid or unenforceable, the remainder of this Lease, or the application of
such provision to persons or circumstances other than those as to which it is
invalid or unenforceable, shall not be affected thereby, and each provision of
this Lease shall be valid and be enforceable to the full extent permitted by
law.

                  Section 19.19. AUTHORITY. If Tenant executes this Lease as a
corporation, a partnership or limited liability company, each of the persons
executing this Lease on behalf of Tenant does hereby covenant and warrant that
Tenant is a duly authorized and existing entity, that Tenant has full right and
authority to enter into this Lease, and that each and all of the persons on
behalf of Tenant are authorized to do so. Upon Landlord's request, Tenant shall
provide Landlord with evidence reasonably satisfactory to Landlord confirming
the foregoing covenants and warranties.

                  Section 19.20. NO OFFER. No contractual or other rights shall
exist between Landlord and Tenant with respect to the Premises until both have
executed and delivered this Lease, notwithstanding that Landlord has delivered
to Tenant an unexecuted copy of this Lease. The submission of this Lease to
Tenant shall not constitute the grant of an option for the Tenant to lease, or
otherwise create any interest by Tenant in, the Premises or any other premises
in the Building or Project. The execution of this Lease by Tenant and return to
Landlord shall not be binding upon Landlord, notwithstanding any time interval,
until Landlord has in fact executed and delivered this Lease to Tenant.


                                       41
<PAGE>

                  Section 19.21. NO REPRESENTATIONS OR WARRANTIES. Neither
Landlord nor Landlord's members, partners, employees, agents or contractors have
made any representations or warranties with respect to the Premises, the
Building, the Project or this Lease, except as expressly set forth herein.

                  Section 19.22. BROKERS. Each party hereto represents and
warrants that it has dealt with no broker, finder or salesperson in connection
with this Lease, other than Landlord's Broker and Tenant's Broker listed in the
Basic Lease Information, and each party hereto shall indemnify, defend and hold
the other party harmless from and against and all losses, costs, claims,
damages, liabilities or causes of action (including attorney's fees) arising out
of or relating to any breach of the foregoing representation and warranty or
arising out of or relating to any claim made by any broker, finder or
salesperson claiming to have dealt with the indemnifying party.

                  Section 19.23.  AMENDMENTS.  This Lease may not be modified or
amended except by an instrument in writing executed by both parties hereto.

                  Section 19.24. NAME. Tenant shall not use the name of the
Building or the Project for any purpose other than as an address of the business
to be conducted by Tenant in the Premises. The name of the Building and/or the
Project may be changed from time to time in Landlord's sole discretion.

                  Section 19.25. SIGNS, DIRECTORY. Tenant shall have the right
to place a sign identifying Tenant's occupancy of the Premises on the existing
monument sign for the Building, if any, on the Building and in any directory in
the Building lobby, in each case subject to Landlord's prior written consent,
which consent shall not be unreasonably withheld by Landlord. All signs so
consented to by Landlord and placed by Tenant on any monument sign for the
Building or upon or in the Building or Premises shall be fabricated and
installed by Tenant at its sole cost and expense and shall comply in all
respects with size, design, lettering and material guidelines established from
time to time by Landlord for the Project. Landlord reserves the right to change
or alter such guidelines at such times and for such tenants as Landlord may
determine. Tenant shall comply with all applicable statutes, ordinances, rules
and regulations of governmental authorities with respect to any such signs.

                  Section 19.26. PARKING. Tenant, at no cost or expense to
Tenant, shall have the non-exclusive use of not more than One Hundred
Eighty-Four (184) of the parking spaces in the parking areas of the Project for
the parking of motor vehicles by Tenant's employees working on the Premises.
Landlord shall have the right to relocate such non-exclusive parking spaces from
time to time to other parking areas in or adjacent to the Project. Landlord
shall have no obligation to monitor or police the use of any parking areas or
otherwise to assure Tenant or its employees of the availability of any parking
spaces. Notwithstanding the foregoing, Landlord shall from time to time have


                                       42
<PAGE>

the right to institute and maintain procedures for controlling the use of the
parking areas in the Project, including, without limitation, through the
issuance of stickers or badges to be displayed on the vehicles of authorized
users of the parking areas. Tenant shall cause its employees to comply with any
such procedures instituted and maintained by Landlord from time to time.

                  Section 19.27. BUILDING ACCESS. Landlord shall provide Tenant
with Two Hundred Fifty (250) building access cards for the Building at a cost of
$10 per card. Tenant shall return all such building access cards to Landlord
upon the expiration or early termination of the Term of this Lease. Tenant shall
pay to Landlord such charges as Landlord shall impose from time to time with
respect to any building access card not returned or damaged.

                  Section 19.28. LANDLORD AMENITIES. Notwithstanding anything to
the contrary contained in this Lease, Tenant and its employees shall have the
right to use, in common with the Landlord, its employees, agents, and invitees,
and any other parties to whom Landlord shall grant such rights (a) the
volleyball court, basketball court, picnic tables and lawn area immediately
adjacent to the Premises, and (b) the cafeteria located in the Administration
Building of the Project during Landlord's hours of operation of the cafeteria
from time to time. Tenant's rights under this Section shall be subject to such
rules and regulations, and amendments thereto, as Landlord shall promulgate from
time to time. In no event shall Landlord be obligated to operate the cafeteria
for Tenant's benefit, and Landlord shall have the right to change or reduce
Landlord's hours of operation of the cafeteria and to discontinue any cafeteria
service entirely, at Landlord's sole option.

                  Section 19.29. CONFERENCE ROOMS. Tenant shall have the
right to use the conference room on the first floor of the Administration
Building ("Conference Room") from time to time ("Use Periods") during the
Term. Tenant shall schedule each such Use Period with Landlord in writing a
reasonable period of time in advance of the date of such Use Period, and
availability of the Conference Room shall be subject to the prior right of
use by Landlord, its employees, agents or invitees and other tenants.

                  (b)      Tenant shall pay to Landlord, at the same time and in
the same manner as the payment of Monthly Base Rent, a charge calculated in
accordance with Section 7.3 above for each Use Period. Landlord shall cause the
Conference Room to be unoccupied and available for Tenant's use during the Use
Periods. At the end of each Use Period, Tenant shall leave the Conference Room
in the same condition as it was prior to such Use Period and shall remove
therefrom any garbage or debris created by Tenant and any other parties using
the Conference Room during such Use Period.

                  Section 19.30. SECURITY, CUSTOMER SERVICE AREA. If at any time
during the Term of this Lease, Landlord shall no longer require the security and
customer service


                                       43
<PAGE>

area located on the first floor of the Building and not included in the
Premises, and shall vacate such security and customer service area, such
security and customer service area shall thereupon become a part of the
Premises. Landlord and Tenant shall promptly execute and deliver an appropriate
amendment to this Lease providing for (a) incorporation of such security and
customer service area within the Premises; (b) Tenant's payment of Monthly Base
Rent with respect to such security and customer service area at the rental rate
then provided for under this Lease with respect to the balance of the Premises,
subject to such increases as are provided for under this Lease; (c) an
appropriate adjustment to Tenant's Share; and (d) such other reasonable terms
and provisions as Landlord and Tenant shall agree upon. In no event shall
Landlord be obligated to make any alterations, additions, improvements or
repairs to such security and customer service area, and Tenant shall accept
possession of such security and customer service area in its "as-is" condition.
The security and customer service area consists of 3,672 square feet of rentable
area.

                  (b)      At Tenant's request and upon Landlord's reasonable
approval, Landlord shall caused to be installed a demising wall or door
separating such security and customer service area from the Premises. If
Landlord shall install such demising wall or door, Landlord shall cause such
demising wall or door to be removed following Landlord's vacating such security
and customer service area. Landlord and its employees, agents and contractors
occupying such security and customer service area shall have the reasonable
right to use the restrooms and similar amenities and facilities in the Premises
from time to time. Apart from such use, such occupants shall not enter upon the
Premises and Tenant, its employees, agents and contractors shall not enter upon
such security and customer service area (including through use of the stairway
connecting such areas), except in the case of an emergency requiring such
access.

                  Section 19.31. ANTENNA. Notwithstanding anything to the
contrary contained in this Lease, as long as space is available on the roof of
the Building, Tenant, at its sole cost and expense, shall have the right to
install, operate and maintain an antenna ("Antenna") on the roof of the Building
in a location reasonably approved by Landlord. The size and design
specifications for the Antenna, and the manner in which the Antenna shall be
installed, shall be subject to the reasonable prior written approval of
Landlord. Tenant's installation, operation and maintenance of the Antenna shall
be subject to the following terms and conditions:

                  (a)      Tenant's right to install, operate and maintain the
Antenna shall be subject to all applicable governmental laws, rules and
regulations, and any private covenants, conditions, and restrictions and subject
to Tenant obtaining all required licenses, permits and approvals of governmental
authorities, and Landlord makes no representation or warranty that such laws,
rules and regulations, or private covenants, conditions and restrictions allow
such installation, operation and maintenance;


                                       44
<PAGE>

                  (b)      All costs of installation, operation and maintenance
of the Antenna and the connecting cable (including, without limitation, labor
costs for routing the cable and costs of obtaining any necessary permits) shall
be borne by Tenant;

                  (c)      It is expressly understood that Landlord retains the
right to use the roof of the Building for any purpose whatsoever and to relocate
the Antenna provided that Landlord shall not unreasonably interfere with the use
of the Antenna;

                  (d)      Tenant shall use the Antenna so as not to cause any
interference to Landlord or to other tenants in the Building or Project or with
Landlord's or any other tenant's communication equipment and so as not to damage
or interfere with the operation of the Building or Project;

                  (e)      Landlord shall not have any obligations with respect
to the maintenance or repair of the Antenna, and Landlord shall not be
responsible for any damage that may be caused to Tenant or to the Antenna by any
other tenant in the Building or Project. Landlord makes no representation or
warranty that the Antenna will be able to receive or transmit communication
signals without interference or disturbance and Tenant agrees that Landlord
shall not be liable to Tenant therefor;

                  (f)      Tenant shall (i) be solely responsible for any damage
caused as a result of the Antenna, including damage to the Building, (ii)
promptly pay any tax, license or permit fees charged pursuant to any laws or
regulations in connection with the installation, maintenance or use of the
Antenna and comply with all precautions and safeguards recommended by all
governmental authorities, (iii) pay for all necessary repairs, replacements to
or maintenance of the Antenna, and (iv) indemnify, defend and hold Landlord
harmless from and against any and all losses, costs, claims, damages,
liabilities and causes of action (including attorneys' fees and costs) arising
out of or in any way connected with the installation, operation or removal of
the Antenna;

                  (g)      Tenant shall remove the Antenna and connecting cable
at Tenant's expense upon the expiration or earlier termination of the Lease or
upon the imposition of any governmental law or regulation which may require
removal, and shall repair any damage caused by such removal; and

                  (h)      Tenant's rights hereunder with respect to such
Antenna shall be non-exclusive and Landlord itself shall have the right, and
Landlord may permit others, to install and maintain antenna, satellite dishes
and similar facilities on the Building.

                  Section 19.32. EXHIBIT. Attached hereto is EXHIBIT A, which is
hereby incorporated herein by reference.


                                       45
<PAGE>

                  IN WITNESS WHEREOF, Landlord and Tenant have executed this
Lease as the date set forth in the Basic Lease Information.

LANDLORD:                             TYCO ELECTRONICS CORPORATION,
                                      a Pennsylvania corporation

                                      By:
                                             ---------------------------------
                                      Title:
                                             ---------------------------------


TENANT:                               INTERWAVE COMMUNICATIONS, INC.,
                                      a Delaware corporation

                                      By:        [Illegible]
                                             ---------------------------------
                                      Title:       EVP CFO
                                             ---------------------------------


                                       46
<PAGE>

                                  EXHIBIT "A"

                                  FLOOR PLAN

                               showing the layout
                              of the leased space

                                       1