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                                                                   EXHIBIT 10.17

                           CHARLESTON BUSINESS PARK
               STANDARD NNN LEASE -- Multi-Tenant Business Park

                                  WITNESSETH

This lease ("Lease") is entered into by and between Limar Realty Corp. #17, a
California corporation ("Landlord") and Docent, Inc., a Delaware corporation
("Tenant"). For and in consideration of the payment of rents and the performance
of the covenants herein set forth by Tenant, Landlord does lease to Tenant and
Tenant accepts the Premises described below subject to the agreements herein
contained.

1.    BASIC LEASE TERMS

      a.    DATE OF LEASE:              September 22, 1999

      b.    TENANT:                     Docent, Inc.

            Address (of the Premises):  2444 Charleston Road, Mountain View, CA
                                      94043

            Address (for Notices):  (Please provide if other than Premises.)

      c.    LANDLORD:               Limar Realty Corp. #17

            Address (for Notices):  1730 South El Camino Real
                                    Suite 400
                                    San Mateo, California 94402
                                    Attn: Thomas A. Numainville

      d.    TENANT'S USE OF PREMISES: General office use and research and
            development for software and media products, sale and storage of
            software products and customer training.

      e.    PREMISES AREA:          "Temporary Premises": 2410 Charleston
                                    Road = 12,000 Rentable Square Feet

                                    "Original Premises": 2444 Charleston
                                    Road = 12,200 Rentable Square Feet

                                    "Expansion Premises": 2454 Charleston
                                    Road = 13,800 Rentable Square Feet

                                    The Temporary Premises, Original Premises,
                                    and Expansion Premises are sometimes
                                    collectively and/or individually referred to
                                    herein as the Premises, provided however,
                                    that the Premises shall only refer to space
                                    actually delivered to Tenant pursuant to
                                    this Lease.

      f. BUILDING:                  2444-2454 Charleston Road and/or 2410
                                    Charleston Road as/when occupied by Tenant,
                                    as the case may be

      g. BUSINESS PARK:             Charleston Business Park

      h. INSURING PARTY:            Landlord is the "Insuring Party" unless
                                    otherwise stated herein.

      i. TERM (inclusive):          Commencement Date: See (P)29.

                                    Expiration Date: See (P)30.

                                    Number of Months from Temporary Premises
                                    Commencement Date to Expiration Date of the
                                    Original Premises and the Expansion
                                    Premises: 68 (assumes 10/1/99 Temporary
                                    Premises Commencement Date)

      j  TENANT'S SHARE OF BUILDING:               See (P)31

      k. TENANT'S SHARE OF BUSINESS PARK:          See (P)31.

      l. TENANT'S NUMBER OF NON-RESERVED PARKING SPACES:       See (P)32.

      m. INITIAL BASE RENT                         See (P)33.

      n. BASE RENT ADJUSTMENT:                     See (P)34.

      o. PREPAID BASE RENT:                        As to the Temporary
                                                   Premises = $30,000.00

      p. SECURITY DEPOSIT:                         See (P)36.

      q. BROKER(S):                                Cornish & Carey Commercial

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      r.    EXHIBITS: Exhibits lettered "A" through "D" are attached hereto and
            made a part hereof.

2.    PREMISES, PARKING AND COMMON AREAS

      a.    Premises. The Premises as described in (P) 1. and Exhibit A, are a
                                                              ---------
            portion of a building, herein sometimes referred to as the
            "Building" identified in (P) 1. The Premises, the Building, the
            Common Areas, the ;land upon which the same are located, along with
            all other buildings and improvements thereon or thereunder, are
            herein collectively referred to as the "Business Park" as described
            in (P) 1. and Exhibit B Landlord hereby leases to Tenant and Tenant
                          ---------
            leases from Landlord for the Term (as defined below), at the rental,
            and upon all of the conditions set forth herein, the real property
            referred to in the Basic Lease Terms, (P) 1 as the "Premises",
            including rights to the Common Areas as hereinafter specified.
            Subject to any additional work Landlord has agreed herein to do,
            Tenant hereby accepts the Premises in their condition existing as of
            the date of the execution hereof, subject to all applicable zoning,
            municipal, county and state laws, ordinances and regulations
            governing and regulating the use of the Premises, and accepts this
            Lease subject thereto and to all matters disclosed thereby and by
            any exhibits attached hereto. Tenant agrees with the square footage
            specified for the Premises in (P) 1. and will not hereafter
            challenge such determination and agreement. The rental payable by
            Tenant pursuant to this Lease is not subject to revision in the
            event of any discrepancy in the rentable square footage for the
            Premises.

      b     Vehicle Parking. So long as Tenant is not in default, and subject to
            the Rules and Regulations attached hereto as Exhibit C, and as
                                                         ---------
            established by Landlord from time to time, Tenant shall be entitled
            to use the number of parking spaces set forth in (P) 1. If Tenant
            commits, permits or allows any of the prohibited activities
            described in the Lease or the Rules and Regulations then in effect,
            then Landlord shall have the right, without notice, in addition to
            such other rights and remedies that it may have, to remove or tow
            away the vehicle involved and charge the cost to Tenant, which cost
            shall be immediately payable upon demand by Landlord. Landlord shall
            have the right following reasonable notice to Tenant, at any time
            during the Lease Term, to implement a parking plan for the Business
            Park whereby one or more of the tenants in the Business Park will be
            allocated a designated portion of the Common Areas for the exclusive
            parking by such tenant provided there is no disproportionate
            reduction to the number of spaces allocated to Tenant In the event
            Landlord elects to implement such parking plan for tenant(s)
            representing at least 25% of the square footage in the Business
            Park, Landlord shall provide Tenant with the exclusive right to park
            in a designated portion of the Common Areas (which designated
            portion shall be approximately located on all or a portion of the
            Common Areas identified on Exhibit "A" attached hereto).

      c.    Common Areas -- Definition. The term "Common Areas" is defined as
            all areas and facilities outside the Premises and within the
            exterior boundary line of the Business Park that are provided and
            designated by the Landlord from time to time for the general
            non-exclusive use of Landlord, Tenant and of other tenants of the
            Business Park and their respective employees, suppliers, shippers,
            customers and invitees, including but not limited to common
            entrances, lobbies, corridors, stairways and stairwells, public
            restrooms, elevators, parking areas to the extent not otherwise
            prohibited by this Lease, loading and unloading areas, trash areas,
            roadways, sidewalks, walkways, parkways, ramps, driveways,
            landscaped areas and decorative walls.

      d.    Common Areas - Rules and Regulations. Tenant agrees to abide by and
            conform to the Rules and Regulations attached hereto as Exhibit C
                                                                    ---------
            with respect to the Business Park and Common Areas, and to cause its
            employees, suppliers, shippers, customers and invitees to so abide
            and conform. Landlord, or such other person(s) as Landlord may
            appoint, shall have the exclusive control and management of the
            Common Areas and shall have the right, from time to time, to
            reasonably modify, amend and enforce said rules and regulations.
            Landlord shall not be responsible to Tenant for the non-compliance
            with said rules and regulations by other tenants, their agents,
            employees and invitees, Following a written request from Tenant,
            Landlord shall use commercially reasonable efforts to enforce the
            rules and regulations against other tenants of the Building subject
            to the terms of each tenant's lease.

      e.    Building and Common Areas -- Changes. Landlord shall have the right,
            in Landlord's reasonable discretion, from time to time:

            1)    To make changes to the Building interior and exterior and
                  Common Areas, including, without limitation, changes in the
                  location, size, shape, number and appearance thereof,
                  including but not limited to the lobbies, windows, stairways,
                  air shafts, elevators, restrooms, driveways, entrances,
                  parking spaces, parking areas, loading and unloading areas,
                  ingress, egress, direction of traffic. decorative walls,
                  landscaped areas and walkways;

            2)    To close temporarily any of the Common Areas for maintenance
                  purposes so long as reasonable access to the Premises remains
                  available;

            3)    To designate other land and improvements outside the
                  boundaries of the Business Park to be a part of the Common
                  Areas, provided that such other land and improvements have a
                  reasonable and functional relationship to the Business Park;

            4)    To add additional buildings and improvements to the Common
                  Areas;

            5)    To use the Common Areas while engaged in making additional
                  improvements, repairs or alterations to the Business Park or
                  any portion thereof; and

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            6)    To do and perform such other acts and make such other changes
                  in, to or with respect to the Common Areas and Business Park
                  as Landlord may, in the exercise of sound business judgment
                  deem to be appropriate. Landlord's rights pursuant to this (P)
                  2.e. shall be subject to the condition that exercise of any
                  such rights shall not unreasonably interfere with Tenant's use
                  of the Premises or disproportionately decrease the number of
                  Tenant's parking spaces.

      f.    Acceptance; Quiet Enjoyment. Landlord represents that it is the fee
            simple owner of the Premises and has full right and authority to
            make this Lease. Landlord hereby leases the Premises to Tenant and
            Tenant hereby accepts the same from Landlord, in accordance with the
            provisions of this Lease. Landlord covenants that Tenant shall have
            peaceful and quiet enjoyment of the Premises during the Term (as
            defined below) of this Lease. Tenant covenants that it will not
            interfere with other tenants' quiet enjoyment of their premises.

3.    TERM. The term ("Term") of this Lease is for the period that commences at
      12:01 a.m. on the Temporary Premises Commencement Date and expires at
      11:59 p.m. on the Expiration Date of the Original Premises and the
      Expansion Premises. If Landlord, for any reason, cannot deliver possession
      of the Temporary Premises to Tenant on or before the Temporary Premises
      Commencement Date, this Lease shall not be void or voidable, nor shall
      Landlord be liable to Tenant for any loss or damage resulting from such
      delay, In that event, however, there shall be an abatement of Base Rent
      (as defined below) and additional rent covering the period between the
      Temporary Premises Commencement Date and the date when Landlord delivers
      possession to Tenant, and all other terms and conditions of this Lease
      shall remain in full force and effect. If a delay in possession is caused
      by Tenant's failure to perform any obligation in accordance with this
      Lease, the Term shall commence as of the Temporary Premises Commencement
      Date, and the abatement of Base Rent and additional rent shall continue
      only until the date Landlord would have delivered possession but not for
      Tenant's failure.

4.    RENT

      a.    Base Rent. Tenant shall pay Landlord in lawful money of the United
            States, without notice, demand. offset or deduction, rent in the
            amount(s) set forth in (P) 1. which shall be payable in advance on
            the first day of each and every calendar month ("Base Rent")
            provided, however, the first month's Base Rent is due and payable
            upon execution of this Lease. Unless otherwise specified in writing
            by Landlord, all installments of Base Rent shall be payable to Limar
            Realty Corp. #17, Department #44294, P.O. Box 44000, San Francisco,
            California 94144-4294. Base Rent for any partial month at the
            beginning or end of this Lease will be prorated in accordance with
            the number of days in the subject month.

            For purposes of Section 467 of the Internal Revenue Code. the
            parties to this Lease hereby agree to allocate the stated Base Rent
            provided herein to the periods which correspond to the actual Base
            Rent payments as provided under the terms and conditions of this
            Agreement.

      b.    Cost of Living Adjustment. As to the Original Premises (See (P)
            34.b.), the Base Rent shall be subject to increase on April 1 in the
            years of 2000. 2001, 2002 and 2003. The base for computing the
            increase is the Consumer Price Index All Urban Consumers for the
            CMSA referenced in (P) 34.b.1) (1982-84 base year = 100), published
            by the United States Department of Labor, Bureau of Labor Statistics
            ("Index"), which is in effect on the ninetieth (90th) day preceding
            April 1, 1999 ("Beginning Index"). The Index ("Adjustment Index")
            published and in effect on the ninetieth (90th) day preceding each
            annual anniversary ("Annual Anniversary") of April 1, 1999 is to be
            used in determining the amount of the increase from one year to the
            next. Beginning with the Base Rent due on and after the first
            anniversary, the Base Rent shall be increased to equal the product
            achieved by multiplying the Base Rent amount by a fraction, the
            numerator of which will be the Adjustment Index and the denominator
            of which will be the Beginning Index. If there is a decline from one
            Annual Anniversary to the next in the Adjustment Index. the Base
            Rent due during the subsequent lease year shall equal the Base Rent
            due during the then present lease year (i.e., there shall be no
            decrease in Base Rent). Notwithstanding the foregoing provisions of
            this (P) 4.b.), each Base Rent adjustment shall be subject to a
            minimum adjustment in accordance with the Floor Limit if specified
            in (P) 34.b.1) and a maximum adjustment in accordance with the
            Ceiling Limit if specified in (P) 34.b.1).

            If the Index is changed so that the base year differs from 1982-84 =
            100, the Index shall be converted in accordance with the conversion
            factor published by the United States Department of Labor, Bureau of
            Labor Statistics, If the Index is discontinued or revised during the
            Term, such other government index or computation with which it is
            replaced shall be used in order to obtain substantially the same
            result as, in Landlord's reasonable opinion, would be obtained if
            the Index had not been discontinued or revised.

      c.    Step Increase. The Base Rent shall be increased periodically to the
            amounts and at the times set forth in (P) 34.

      d.    Rent Without Offset and Late Charge. All Rent shall be paid without
            prior demand or notice and without any deduction or offset
            whatsoever. All Rent shall be paid in lawful currency of the United
            States of America. Tenant acknowledges that late payment by Tenant
            to Landlord of any Rent will cause Landlord to incur costs not
            contemplated by this Lease, the exact amount of such cost 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
            encumbrance or note secured by the Premises. Therefor, if any Rent
            is not received by Landlord within five (5) days of its due date,
            Tenant

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            shall pay to Landlord a late charge equal to six percent (6%) of
            such overdue payment. Landlord and Tenant hereby agree that such
            late charge represents a fair and reasonable estimate of the costs
            that Landlord will incur by reason of any such late payment and that
            the late charge is in addition to any and all remedies available to
            the Landlord and that the assessment and/or collection of the late
            charge shall not be deemed a waiver of any other default.
            Additionally, all such delinquent Rent or other sums, plus this late
            charge, shall bear interest from the due date thereof at the lesser
            of ten percent (10%) per annum or the maximum legal interest rate
            permitted by law. Any payments of any kind returned for insufficient
            funds will be subject to an additional handling charge of $25.00,
            and thereafter for the remainder of the Term hereof, Landlord may
            require Tenant to pay all future payments of Rent or other sums due
            by cashier's check.

      e.    Prepaid Base Rent. Upon the execution of this Lease, Tenant shall
            pay to Landlord the Prepaid Base Rent set forth in (P) 1., and such
            Prepaid Base Rent shall be applied toward the Base Rent due for the
            first month of the Term for which Rent is due.

      f     Rent. The term "Rent" as used in this Lease shall refer to Base
            Rent, Prepaid Base Rent, Real Property Taxes, Operating Expenses,
            Insurance Costs, repairs and maintenance costs, utilities, late
            charges and other similar charges payable by Tenant pursuant to this
            Lease either directly to Landlord or otherwise.

5.    OPERATING EXPENSES.

      a.    Payment by Tenant. During the Term of this Lease, Tenant shall pay
            to Landlord, as additional Rent, on a monthly basis Tenant's Share
            of the Operating Expenses. To the extent that Operating Expenses are
            accounted for on a building by building basis, the Tenant's Share of
            Building shall apply. To the extent that Operating Expenses are
            accounted for on an overall Business Park basis, then Tenant's Share
            of Business Park shall apply.

      b     Operating Expenses. The term "Operating Expenses" shall mean all
            expenses, costs and disbursements (not specifically excluded from
            the definition of Operating Expenses below) of every kind and nature
            which Landlord shall pay or become obligated to pay because of or in
            connection with the ownership, maintenance, repair and operation of
            the Business Park or any portion thereof (including all Buildings
            and Common Areas of the Business Park). Operating Expenses shall
            include, but not be limited to, the following:

            1)    Wages and salaries of all employees engaged in the operation,
                  maintenance and security of the Business Park, including
                  taxes, insurance and benefits relating thereto; and the rental
                  cost and overhead of any office and storage space used to
                  provide such services.

            2)    All supplies and materials used in the operation, repair or
                  maintenance of the Business Park

            3)    Cost of all utilities, including surcharges, for the Business
                  Park, including the cost of water, power and lighting which
                  are not separately billed to and paid for by Tenant.

            4)    Cost of all maintenance and service agreements for the
                  Business Park and the equipment thereon, including but not
                  limited to, security services, exterior window cleaning,
                  janitorial service, engineers, gardeners and trash removal
                  services.

            5)    All Insurance Costs, as such term is defined in (P) 16.

            6)    Cost of repairs and general maintenance (excluding repairs and
                  general maintenance paid by proceeds of insurance or by Tenant
                  or other third parties, and alterations attributable solely to
                  the other tenants of the Business Park).

            7)    A reasonable management fee for the property management of the
                  Business Park.

            8)    The costs of any additional services not provided to the
                  Business Park at the Commencement Date but thereafter provided
                  by Landlord to all tenants in its management of the Business
                  Park.

            9)    The cost of any capital improvements to the Business Park or
                  any part thereof which are made during the Term hereof
                  amortized over the useful life of the improvement.

            10)   Real Property Taxes, as that term is defined in (P) 11.

            11)   Assessments, dues and other amounts payable pursuant to the
                  CC&R's described in (P) 7.c.

            12)   All costs to maintain, repair and replace the heating,
                  ventilation and air conditioning systems ("HVAC") serving the
                  Building and/or the Premises, including the cost of
                  maintenance contracts.

      c.    Operating Expenses shall not include:

            1)    Costs paid for directly by Tenant or other tenants;

                                      -4-
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            2)    Principal and interest payments on loans secured by deeds of
                  trust recorded against the Business Park or the Building of
                  which the Business Park is a part;

            3)    Real estate sales or leasing brokerage commissions;

            4)    Executive salaries of off-site personnel employed by Landlord
                  except for the charge (or prorata share) of the property
                  manager of the Business Park;

            5)    Leasing commissions, attorneys' fees, costs, disbursements and
                  other expenses incurred in connection with negotiations or
                  disputes with tenants, or in connection with leasing,
                  renovating or improving space for tenants or other occupants
                  or prospective tenants or other occupants of the Business
                  Park;

            6)    The cost of any service sold to any tenant (including Tenant)
                  or other occupant for which Landlord is entitled to be
                  reimbursed as an additional charge or rental over and above
                  the basic rent and escalations payable under the lease with
                  that tenant;

            7)    Any depreciation on the Building or Business Park;

            8)    Expenses in connection with services or other benefits of a
                  type that are not provided to Tenant but which are provided
                  another tenant or occupant of the Building or Business Park;

            9)    Costs incurred due to Landlord's violation of any terms or
                  conditions of this Lease or any other lease relating to the
                  Building or Business Park;

            10)   Overhead profit increments paid to Landlord's subsidiaries or
                  affiliates for services on or to the Building or for supplies
                  or other materials to the extent that the cost of the
                  services, supplies, or materials exceeds the cost that would
                  have been paid had the services, supplies or materials been
                  provided by unaffiliated parties on a competitive basis;

            11)   Any compensation paid to clerks, attendants or other persons
                  in commercial concessions operated by Landlord;

            12)   Advertising and promotional expenditures;

            13)   Costs or repairs and other work occasioned by fire, windstorm
                  or other casualty of an insurable nature to the extent covered
                  by insurance;

            14)   Management costs to the extent they exceed management costs
                  charged for similar facilities in the area; or

            15)   Costs for sculpture, paintings or other objects of art (nor
                  insurance thereon or extraordinary security in connection
                  therewith).

      d.    Extraordinary Services. Tenant shall pay within ten (10) days of
            receipt of an invoice from Landlord the cost of additional or
            extraordinary services provided to Tenant and not paid or payable by
            Tenant pursuant to other provisions of this Lease.

      e.    Impound. Landlord reserves the right, at Landlord's option, to
            estimate the annual cost of Operating Expenses performed by Landlord
            ("Projected Operating Expenses") and to require same to be paid in
            advance. Tenant shall pay to Landlord, monthly in advance as
            additional Rent, one-twelfth (1/12) of the Projected Operating
            Expenses.

      f.    Adjustment.

            1)    Accounting. Within ninety (90) days (or as soon thereafter as
                  possible) after the close of each calendar year or portion
                  thereof of occupancy, Landlord shall provide Tenant a
                  statement of such year's actual Operating Expenses compared to
                  the Projected Operating Expenses. If the actual Operating
                  Expenses are more than the Projected Operating Expenses then
                  Tenant shall pay Landlord, within ten (10) days of receipt of
                  a bill therefor, the difference. If the actual Operating
                  Expenses are less than the Projected Operating Expenses, then
                  Tenant shall receive a credit against future Operating
                  Expenses payments equal to the difference; provided, that in
                  the case of an overpayment for the final lease year of the
                  Term, Landlord shall credit the difference against any sums
                  due from Tenant to Landlord in accordance with the terms of
                  this Lease; and if no sums are due and unpaid, shall promptly
                  refund the net amount to Tenant.

            2)    Tenant's Right to Audit. Within sixty (60) days after receipt
                  of Landlord's statement setting forth actual Operating
                  Expenses (the "Statement"), Tenant shall have the right to
                  audit at Landlord's local offices, at Tenant's expense,
                  Landlord's accounts and records relating to Operating
                  Expenses. Such audit shall be conducted by a certified public
                  accountant approved by Landlord, which approval shall not be
                  unreasonably withheld. If such audit reveals that Landlord has
                  overcharged Tenant, the amount overcharged shall be paid to
                  Tenant within thirty (30) days after the audit is concluded.
                  In addition, if the Statement exceeds the actual Operating
                  Expenses

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                  which should have been charged to Tenant by more than ten
                  percent (10%), the cost of the audit shall be paid by
                  Landlord.

            3)    Proration. Tenant's liability to pay Operating Expenses shall
                  be prorated on the basis of a 365 (or 366, as the case may be)
                  day year to account for any fractional portion of a year
                  included at the commencement or expiration of the Term of this
                  Lease.

            4)    Survival. Landlord and Tenant's obligations to pay for or
                  credit any increase or decrease in payments pursuant to this
                  (P) 5. shall survive this Lease.

      g.    Failure to Pay. Failure of Tenant to pay any of the charges required
            to be paid under this (P) 5. shall constitute a material default and
            breach of this Lease and Landlord's remedies shall be as specified
            in (P) 21.

6.    SECURITY DEPOSIT. Upon execution of this Lease, Tenant shall deposit a
      security deposit ("Security Deposit") in the amount set forth in (P) 36.
      with Landlord. If Tenant is in default, Landlord can (but without any
      requirement to do so) use the Security Deposit or any portion of it to
      cure the default or to compensate Landlord for any damages sustained by
      Landlord resulting from Tenant's default. Upon demand, Tenant shall
      immediately pay to Landlord a sum equal to the portion of the Security
      Deposit expended or applied by Landlord to restore the Security Deposit to
      its full amount. In no event will Tenant have the right to apply any part
      of the Security Deposit to any Rent due under this Lease. Landlord's
      obligations with respect to the Security Deposit are those of a debtor and
      not a trustee, and Landlord can commingle the Security Deposit with
      Landlord's general funds. Landlord shall not be required to pay Tenant
      interest on the Security Deposit. Each time the Base Rent is increased,
      Tenant shall deposit additional funds with Landlord sufficient to increase
      the Security Deposit to an amount which bears the same relationship to the
      Base Rent as the initial Security Deposit bore to the initial Base Rent.
      If Tenant is not in default at the expiration or termination of this Lease
      and has fully complied with the provisions of (P) 9., (P) 13.d.6) and (P)
      26., Landlord shall return the Security Deposit to Tenant.

7.    USE OF PREMISES

      a.    Tenant's Use. Tenant shall use the Premises solely for the purposes
            stated in (P) 1. and for no other purposes without obtaining the
            prior written consent of Landlord. Tenant acknowledges that neither
            Landlord nor any agent of Landlord has made any representation or
            warranty with respect to the Premises or with respect to the
            suitability of the Premises to the conduct of Tenant's business, nor
            has Landlord agreed to undertake any modification, alteration or
            improvement to the Premises, except as provided in writing in this
            Lease. Tenant shall promptly comply with all laws, statutes,
            ordinances, orders and governmental regulations now or hereafter
            existing affecting the Premises. Tenant shall not do or permit
            anything to be done in or about the Premises or bring or keep
            anything in the Premises that will in any way increase the premiums
            paid by Landlord on its insurance related to the Premises. Tenant
            will not perform any act or carry on any practices that may injure
            the Premises. Tenant shall not use the Premises for sleeping,
            washing clothes or the preparation, manufacture or mixing of
            anything that emits any objectionable odor, noises, vibrations or
            lights onto such other tenants, If, in Landlord's reasonable
            judgment, sound insulation is required to muffle noise produced by
            Tenant on the Premises, Tenant at its own cost shall provide all
            necessary insulation. Tenant shall not do anything on the Premises
            which will overload any existing parking or service to the Premises.
            Pets and/or animals of any type shall not be kept on or about the
            Premises. Tenant covenants that it will not interfere with other
            tenants' quiet enjoyment of their premises. Notwithstanding the
            foregoing or anything to the contrary contained in this Lease,
            Tenant shall not be responsible for compliance with any laws, codes,
            ordinances or other governmental directives where such compliance is
            not related specifically to Tenant's use and occupancy of the
            Premises.

      b.    Rules and Regulations. Tenant shall comply with and use the Premises
            in accordance with the Rules and Regulations attached hereto as
            Exhibit C and to any reasonable modifications to such Rules and
            ---------
            Regulations as Landlord may adopt from time to time. Notwithstanding
            the foregoing or anything to the contrary contained in this Lease,
            if any rule or regulation is in conflict with any term, covenant or
            condition of this Lease, this Lease shall prevail. In addition, no
            such rule or regulation, or any subsequent amendment thereto adopted
            by Landlord, shall in any way materially alter, reduce or adversely
            affect any of Tenant's rights or materially enlarge Tenant's
            obligations under this Lease.

      c.    CC&R's. Tenant agrees that this Lease is subject and subordinate to
            the Covenants, Conditions and Restrictions, a copy of which is
            attached hereto as Exhibit D, as they may be amended from time to
                               ---------
            time ("CC&R's"), and further agrees that the CC&R's are an integral
            part of this Lease. Throughout the Term of any extension thereof,
            notwithstanding any other provision hereof, Tenant shall faithfully
            and timely comply with the CC&R's and any modifications or
            amendments thereto. The CC&R's may require the payment of periodic
            or special dues or assessments against the Premises, Such dues and
            assessments shall be included within the definition of Operating
            Expenses pursuant to (P) 5.b.11), and Tenant shall pay its pro rata
            share of such amounts as further set forth in (P) 5. Tenant shall
            hold Landlord, its subsidiaries, shareholders, directors, officers,
            agents and employees harmless and indemnify Landlord, its
            subsidiaries, shareholders, directors, officers, agents and
            employees against any loss, expense and damage, including attorneys'
            fees and costs, arising out of the failure of Tenant to comply with
            the CC&R's.

                                      -6-
<PAGE>

8.    EMISSIONS; STORAGE, USE AND DISPOSAL OF WASTE

      a.    Emissions. Tenant shall not:

            1)    Knowingly permit any vehicle on the Premises or in the Commons
                  Areas to emit exhaust which is in violation of any
                  governmental law, rule, regulation or requirement;

            2)    Discharge, emit or permit to be discharged or emitted, any
                  liquid, solid or gaseous matter, or any combination thereof,
                  into the atmosphere or on, into or under the Premises, any
                  building or other improvements of which the Premises are a
                  part, or the ground or any body of water which matter. as
                  reasonably determined by Landlord or any governmental entity
                  to be in violation of law or regulation, and does or may
                  pollute or contaminate the same, or is, or may become,
                  radioactive or does, or may, adversely affect (a) the health
                  or safety of persons, wherever located, whether on the
                  Premises or anywhere else, (b) the condition, use or enjoyment
                  of the Premises or any other real or personal property,
                  whether on the Premises or anywhere else, or (c) the Premises
                  or any of the improvements thereto including buildings,
                  foundations, pipes, utility lines, landscaping or parking
                  areas;

            3)    Produce, or permit to be produced, any intense glare, light or
                  heat in violation of law or regulations;

            4)    Create, or permit to be created, any sound pressure level
                  which will interfere with the quiet enjoyment of any real
                  property outside the Premises, or which will create a nuisance
                  or violate any governmental law, rule, regulation or
                  requirement;

            5)    Create, or permit to be created, any vibration that is
                  discernible outside the Premises; or

            6)    Transmit, receive or permit to be transmitted or received from
                  or to the Premises. any electromagnetic, microwave or other
                  radiation which is or may be harmful or hazardous to any
                  person or property in, or about the Premises, or anywhere
                  else.

      b.    Storage and Use.

            1)    Storage. Subject to the uses permitted and prohibited to
                  Tenant under this Lease, Tenant shall store in appropriate
                  leak proof containers all solid, liquid or gaseous matter, or
                  any combination thereof, which matter, if discharged or
                  emitted into the atmosphere, the ground or any body of water
                  would be in violation of law or regulation, and does or may
                  (a) pollute or contaminate the same, or (b) adversely affect
                  the (i) health or safety of persons, whether on the Premises
                  or anywhere else, (ii) condition, use or enjoyment of the
                  Premises or any real or personal property, whether on the
                  Premises or anywhere else, or (iii) Premises.

            2)    Use. In addition, without Landlord's prior written consent,
                  Tenant shall not use, store or permit to remain on or about
                  the Premises any solid, liquid or gaseous matter which is, or
                  may become dangerously radioactive. If Landlord does give its
                  consent, Tenant shall store the materials in such a manner
                  that no radioactivity will be detectable outside a designated
                  storage area and Tenant shall use the materials in such a
                  manner that (a) no real or personal property outside the
                  designated storage area shall become contaminated thereby and
                  (b) there are and shall be no adverse effects on the (i)
                  health or safety of persons, whether on the Premises or
                  anywhere else, (ii) condition, use or enjoyment of the
                  Premises or any real or personal property thereon or therein,
                  or (iii) Premises or any of the improvements thereto or
                  thereon.

            3)    Hazardous Materials. Subject to the uses permitted and
                  prohibited to Tenant under this Lease, Tenant shall store,
                  use, employ, transport and otherwise deal with all Hazardous
                  Materials (as defined below) employed on or about the Premises
                  in accordance with all federal, state. Or local law,
                  ordinances, rules or regulations applicable to Hazardous
                  Materials in connection with or respect to the Premises.

      c.    Disposal of Waste.

            1)    Refuse Disposal. Tenant shall not keep any trash, garbage,
                  waste or other refuse on the Premises except in sanitary
                  containers and shall regularly and frequently remove same from
                  the Premises. Tenant shall keep all incinerators, containers
                  or other equipment used for storage or disposal of such
                  materials in a clean and sanitary condition.

            2)    Sewage Disposal. Tenant shall properly dispose of all sanitary
                  sewage and shall not use the sewage disposal system (a) for
                  the disposal of anything except sanitary sewage or (b) amounts
                  in excess of the lesser of: (i) that reasonably contemplated
                  by the uses permitted under this Lease or (ii) that permitted
                  by any governmental entity. Tenant shall keep the sewage
                  disposal system serving the Premises free of all obstructions
                  and in good operating condition.

            3)    Disposal of Other Waste. Tenant shall properly dispose of all
                  other waste or other matter delivered to, stored upon, located
                  upon or within, used on, or removed from the Premises in such

                                      -7-
<PAGE>

                  a manner that it does not, and will not, violate any law or
                  regulation, and adversely affect the (a) health or safety of
                  persons, wherever located, whether on the Premises or
                  elsewhere, (b) condition, use or enjoyment of the Premises or
                  any other real or personal property, wherever located, whether
                  on the Premises or anywhere else, or (c) Premises or any of
                  the improvements thereto or thereon including buildings,
                  foundations, pipes, utility lines, landscaping or parking
                  areas.

      d.    Information. Tenant shall provide Landlord with any and all
            information regarding Hazardous Materials in the Premises, including
            copies of all filings and reports to governmental entities at the
            time they are originated, and any other information requested by
            Landlord. In the event of any accident, spill or other incident
            involving Hazardous Materials, Tenant shall immediately report the
            same to Landlord and supply Landlord with all information and
            reports with respect to the same. All information described herein
            shall be provided to Landlord regardless of any claim by Tenant that
            it is confidential or privileged.

      e.    Compliance with Law. Notwithstanding any other provision in this
            Lease to the contrary, Tenant shall comply with all laws, statutes,
            ordinances, regulations, rules and other governmental requirements
            now or hereafter existing in complying with its obligations under
            this Lease, and in particular, relating to the storage, use and
            disposal of Hazardous Materials.

      f.    Indemnity. Tenant hereby agrees to indemnify, defend and hold
            Landlord, its agents, employees. lenders, shareholders, directors,
            representatives, successors and assigns harmless from and against
            any and all actions, causes of action, losses, damages, costs,
            claims, expenses, penalties, obligations or liabilities of any kind
            whatsoever (including but not limited to reasonable attorneys' fees)
            arising out of or relating to any Hazardous Materials employed,
            used, transported across, or otherwise dealt with by Tenant (or
            invitees, or persons or entities under the control of Tenant) in
            connection with or with respect to the Premises and the Business
            Park. Notwithstanding any of the provisions of this Lease, the
            indemnity obligation of Tenant pursuant to this (P) 8.f. shall
            survive the termination of this Lease and shall relate to any
            occurrence as described in this (P) 8. occurring in connection with
            this Lease. Landlord hereby agrees to indemnify, defend and hold
            Tenant harmless from and against any and all actions, causes of
            action, losses, damages, costs, claims, expenses, penalties,
            obligations or liabilities of any kind whatsoever (including
            reasonable attorneys' fees) arising out of or relating to hazardous
            materials employed, used, transported to the Property, for which the
            Premises are a part thereof, by Landlord, its agents or employees.
            For purposes of this Lease the term "Hazardous Materials" shall mean
            any hazardous, toxic or dangerous waste, substance or material,
            pollutant or contaminant, as defined for purposes of the
            Comprehensive Environmental Response, Compensation and Liability Act
            of 1980 (42 U.S.C. Sections 9601 et seq.), as amended, or the
            Resource Conservation and Recovery Act (42 U.S.C. Sections 6901 et
            seq.), as amended, or any other federal, state, or local law,
            ordinance, rule or regulation applicable to the Premises, or any
            substance which is toxic, explosive, corrosive, flammable,
            infectious, radioactive, carcinogenic, mutagenic, or otherwise
            hazardous, or any substance which contains gasoline, diesel fuel or
            other petroleum hydrocarbons, polychlorinated biphenyls (PCB's), or
            radon gas, urea formaldehyde, asbestos or lead.

9.    SIGNS AND COMMUNICATIONS ANTENNAE. Tenant shall not place any sign or
      communications antennae upon or adjacent to the Premises, except that
      Tenant may, with Landlord's prior written consent, install (but not on the
      roof) such signs as are reasonably required to indicate Tenant's company
      name or logo provided such signs are in compliance with Landlord's
      standard sign criteria or install communications antennae used exclusively
      by Tenant provided such signs and/or communications antennae are in
      compliance with all applicable governmental requirements and the CC&R's,
      The installation of any sign or communications antennae on or adjacent to
      the Premises by or for Tenant shall be subject to the provisions of (P)
      13. (Repairs and Maintenance). Tenant shall remove any sign or
      communications antennae placed on or adjacent to the Premises by Tenant
      upon the expiration of the Term or sooner termination of this Lease, and
      Tenant shall repair any damage or injury to the Premises caused thereby,
      all at Tenant's expense. If any signs or communications antennae are not
      removed, or necessary repairs not made, Landlord shall have the right to
      remove the signs or communications antennae and repair any damage or
      injury to the Premises at Tenant's sole cost and expense. Notwithstanding
      any other provision of this Lease to the contrary, Landlord reserves all
      rights to the use of the roof and the right to install and receive all
      revenues' from the installation of such other signs or communications
      antennae on the Premises, including the roof, as do not unreasonably
      interfere with the conduct of Tenant's business within the Premises.

10.   PERSONAL PROPERTY TAXES. Tenant shall pay at least ten (10) days prior to
      delinquency all taxes assessed against and levied upon Tenant owned
      leasehold improvements, trade fixtures, furnishings, equipment and all
      personal property of Tenant contained in the Premises or elsewhere. When
      possible, Tenant shall cause its leasehold improvements, trade fixtures,
      furnishings, equipment and all other personal property to be assessed and
      billed separately from the real property of Landlord. If any of Tenant's
      said personal property shall be assessed with Landlord's real property,
      Tenant shall pay Landlord the taxes attributable to Tenant within ten (10)
      days prior to delinquency and otherwise after receipt of a written
      statement setting forth the taxes applicable to Tenant's property.

11.   REAL PROPERTY TAXES

      a.    Payment of Taxes. Landlord shall pay the Building's Real Property
            Taxes, as defined in (P) 11.c. during the Term of this Lease.
            Subject to (P) 11.b., Tenant shall promptly reimburse Landlord
            according to (P) 5. for Tenant's Share of Business Park of such Real
            Property Taxes paid by Landlord.

                                      -8-
<PAGE>

      b.    Advance Payment. In. order to ensure payment when due and before
            delinquency of any or all Real Property Taxes, Landlord reserves the
            right, at Landlord's option, to estimate the current Real Property
            Taxes applicable to the Premises, and to require each installment of
            the Real Property Taxes to be paid in advance to Landlord by Tenant,
            either: (i) in a lump sum amount, at least twenty (20) days prior to
            the applicable delinquency date, or (ii) monthly in advance with the
            payment of the Base Rent. If Landlord elects to require payment
            monthly in advance, the monthly payment shall be that equal monthly
            amount which, over the number of months remaining before the month
            in which the applicable tax installment would become delinquent,
            would provide a fund large enough to fully discharge before
            delinquency the estimated installment of Real Property Taxes to be
            paid. When the actual amount of the applicable tax bill is known,
            Landlord may, but is not required to, adjust the amount of such
            equal monthly advance payment so as to provide the funds needed to
            pay the applicable Real Property Taxes before delinquency. If the
            amounts paid to Landlord by Tenant under the provisions of this (P)
            11. are insufficient to discharge the obligations of Tenant to pay
            such Real Property Taxes as the same become due, Tenant shall pay to
            Landlord, upon Landlord's demand, such additional sums as are
            necessary to pay such obligations. All moneys paid to Landlord under
            this (P) 11. may be intermingled with other moneys of Landlord and
            shall not bear interest. In the event of a breach by Tenant in the
            performance of the obligations of Tenant under this Lease, then any
            balance of funds paid to Landlord under the provisions of this (P)
            11. may, at the option of Landlord, be treated as an additional
            Security Deposit under (P) 6.

      c.    Definition of "Real Property Taxes". As used herein, the term "Real
            Property Taxes" shall include any form of real estate tax or
            assessment, general, special, ordinary or extraordinary, and any
            license fee, commercial rental tax, improvement bond or bonds, levy
            or tax or other fee, charge, or excise which may be imposed as a
            substitute for any of the foregoing (other than inheritance,
            personal income or estate taxes) imposed upon the Business Park by
            any authority having the direct or indirect power to tax, including
            any city, county, state or federal government, or any school,
            agricultural, sanitary, fire, street, drainage or other improvement
            district thereof, levied against any legal or equitable interest of
            Landlord in the Business Park, Landlord's right to rent or other
            income therefrom, and/or Landlord's business of leasing the Business
            Park. The term "Real Property Taxes" shall also include any tax.
            fee. levy, assessment or charge, or any increase therein, imposed by
            reason of events occurring, or changes to applicable law taking
            effect, during the Term of this Lease, including but not limited to
            a change in the ownership of the Business Park or in the
            improvements thereon, the execution of this Lease, or any
            modification, amendment or transfer thereof, and whether or not
            contemplated by the parties hereto.

12.   UTILITIES. Tenant shall pay for all water, gas, heat, light, power,
      telephone, trash disposal and other utilities and services supplied to the
      Premises, together with any taxes thereon. If any such 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. Notwithstanding anything to the contrary contained in this
      Lease, Landlord shall use reasonable efforts to restore any service that
      becomes unavailable. Should Tenant be prevented from making reasonable use
      of the Premises for more than thirty (30) consecutive days because of
      Landlord's failure or inability to provide services as stated herein,
      Tenant shall be entitled to abate the rent for each consecutive day (after
      the thirty (30) day period).

13.   REPAIRS AND MAINTENANCE

      a.    Landlord's Obligations. Landlord shall keep the Business Park,
            including the foundation, exterior walls, roof of the Building and
            Common Areas, and the equipment whether used exclusively for the
            Premises or in common with other premises, in good condition and
            repair subject to reimbursement by Tenant in accordance with (P) 5.
            There shall be no abatement of Rent or liability to Tenant on
            account of any injury or interference with Tenant's business with
            respect to any improvements, alterations or repairs made by Landlord
            to the Business Park or any part thereof. Notwithstanding anything
            to the contrary contained in this Lease, Landlord agrees as its
            obligation, under this Lease, to repair, maintain and replace as
            necessary the building structure, support structure, foundation,
            roof (structure and membrane), load bearing walls, plumbing,
            electrical, HVAC, elevator, building exterior and parking grounds
            subject to reimbursement pursuant to (P) 5.

      b.    Tenant's Obligations.

            1)    General. Tenant shall, at Tenant's sole cost and expense and
                  at all times, contract for janitorial services and supplies,
                  keep the Premises in good order, condition and repair,
                  including, without limiting the generality of the foregoing,
                  all equipment or facilities serving the Premises, such as
                  plumbing, heating, air conditioning, ventilating, electrical,
                  lighting facilities, boilers, fired or unfired pressure
                  vessels, fixtures, interior walls, ceilings, floors, windows,
                  window frames, interior and exterior doors and door frames,
                  plate glass and skylights. Tenant shall not cause or permit
                  any Hazardous Material to be spilled or released in, on, under
                  or about the Premises (including through the plumbing or
                  sanitary sewer system) and shall promptly, at Tenant's
                  expense, take all investigatory and/or remedial action
                  reasonably recommended, whether or not formally ordered or
                  required, for the cleanup of any contamination of, and for the
                  maintenance, security and/or monitoring of the Premises, the
                  elements surrounding same, or neighboring properties, that was
                  caused or materially contributed to by Tenant, or pertaining
                  to or involving any Hazardous Materials and/or storage tank
                  brought onto the Premises by or for Tenant or under its
                  control. Tenant, in keeping the Premises in good order,
                  condition and repair, shall exercise and perform good
                  maintenance practices. Tenant's obligations shall include
                  restorations, replacements or

                                      -9-
<PAGE>

                  renewals when necessary to keep the Premises and all
                  improvements thereon or a part thereof in good order,
                  condition and state of repair.

            2)    Contracts. Tenant shall, at Tenant's sole cost and expense,
                  procure and maintain contracts, with copies to Landlord, in
                  customary form and substance for, and with contractors
                  specializing and experienced in, the inspection, maintenance
                  and service of heating, air conditioning and ventilation
                  equipment, if any, servicing the Premises. Tenant shall keep a
                  detailed preventative maintenance schedule and log showing the
                  frequency of maintenance on all HVAC, mechanical, electrical
                  and other systems servicing the Premises and provide Landlord
                  with a copy of same quarterly.

            3)    As-is Condition. Except as otherwise provided herein, the
                  parties affirm that Landlord, its subsidiaries, officers,
                  shareholders, directors, agents and/or employees have made no
                  representations to Tenant respecting the condition of the
                  Premises except as specifically stated herein.

            4)    Americans with Disabilities Act. Tenant acknowledges that as
                  of the Commencement Date. the Premises may not comply with the
                  Americans with Disabilities Act of 1990 ("ADA"). and that
                  Landlord shall have no obligation with respect to any such
                  failure of the Premises to so comply Tenant shall, at its
                  cost, at any time during the Term as required by any
                  applicable governmental agency having jurisdiction over the
                  Premises, make such modifications and alterations to the
                  Premises as may be required in order to fully comply with the
                  provisions of the ADA, as from time to time amended, and any
                  and all regulations issued pursuant to or in connection with
                  the ADA in such a manner as to satisfy the applicable
                  governmental agency or agencies requiring remediation. Tenant
                  shall at least thirty (30) days prior to the commencement of
                  any construction in connection with satisfaction of the ADA,
                  give written notice to Landlord of its intended commencement
                  of construction together with sufficient details so as to
                  reasonably disclose to Landlord the nature of the proposed
                  construction, copies of any notices received by Tenant from
                  applicable governmental agencies in connection with the ADA
                  and such other documents or information as Landlord may
                  reasonably request. In any event, notwithstanding anything to
                  the contrary contained in this Lease, prior to the termination
                  of the Term, Tenant shall, at its Cost, make such
                  modifications and alterations to the Premises as may be
                  required to comply fully with the ADA as from time to time
                  amended and any and all regulations issued thereunder. Tenant
                  shall give the Landlord thirty (30) days prior written notice
                  as described above in connection with any such construction.
                  Any and all construction required to so comply with the ADA
                  shall be completed by Tenant prior to the expiration of the
                  Term.

      c.    Compliance with Governmental Regulations. Tenant shall, at its own
            cost and expense, promptly and properly observe and comply with all
            present and future orders, regulations, directions, rules, laws,
            ordinances, and requirements of all governmental authorities
            (including but not limited to state, municipal. county and federal
            governments and their departments, bureaus, boards and officials)
            arising from the use or occupancy of, or applicable to, the Premises
            or privileges appurtenant to or in connection with the enjoyment of
            the Premises. Tenant shall also comply with all such rules, laws,
            ordinances and requirements at the time Tenant makes any alteration,
            addition or change to the Premises Notwithstanding anything to the
            contrary contained in this Lease, Tenant shall not be responsible
            for compliance with any laws, codes, ordinances or other
            governmental directives where such compliance is not related
            specifically to Tenant's use and occupancy of the Premises.

      d.    Miscellaneous.

            1)    Landlord and Tenant shall each do all acts required to comply
                  with all applicable laws, ordinances and rules of any public
                  authority relating to their respective maintenance obligations
                  as set forth herein.

            2)    Tenant expressly waives the benefits of any statute now or
                  hereafter in effect which would otherwise afford the Tenant
                  the right to make repairs at Landlord's expense or to
                  terminate this Lease because of Landlord's failure to keep the
                  Premises and the Business Park in good order, condition and
                  repair, Specifically, Tenant waives the provisions of
                  California Civil Code Sections 1941 and 1942 with respect to
                  Landlord's obligations for Tenant tenantability of the
                  Premises and Tenant's right to make repairs and deduct the
                  expenses of such repairs from Rent.

            3)    Tenant shall not place a load upon any floor of the Premises
                  which exceeds the load per square foot which such floor was
                  designed to carry, as determined by Landlord or Landlord's
                  structural engineer.

            4)    Except as otherwise expressly provided in this Lease, Landlord
                  shall have no liability to Tenant nor shall Tenant's
                  obligations under this Lease be reduced or abated in any
                  manner whatsoever o by reason of any inconvenience, annoyance,
                  interruption or injury to business arising from Landlord
                  making any repairs or changes which Landlord is required to
                  make or is permitted to make by this Lease or by any tenant's
                  lease or is required by law to make in or to any portion of
                  the Premises. Landlord shall nevertheless use reasonable
                  efforts to minimize any interference with Tenant's business in
                  the Premises.

                                      -10-
<PAGE>

            5)    Tenant shall give Landlord prompt notice of any damage to or
                  defective condition in any part or appurtenance of the
                  Premises' mechanical, electrical, plumbing, HVAC or other
                  systems serving, located in or passing through the Premises.
                  Upon request by Landlord, Tenant shall provide Landlord with
                  evidence reasonably acceptable to Landlord of a service
                  contract on the HVAC systems.

            6)    Upon the expiration or early termination of this Lease, Tenant
                  shall return the Premises to Landlord clean and in the same
                  condition as on the date Tenant took possession, except for
                  normal wear and tear. Any damage to the Premises, including
                  any structural damage, resulting from Tenant's use or from the
                  removal of Tenant's fixtures, furnishings and equipment shall
                  be repaired by Tenant prior to the end of the Term at Tenant's
                  expense.

            7)    Landlord may, at Landlord's option, choose to perform any of
                  the Tenant's obligations in this (P) 13 The cost of any such
                  Tenant's obligations so performed by Landlord shall be at
                  Tenant's sole cost and expense. Tenant shall reimburse
                  Landlord for any such COSTS incurred by Landlord in the
                  performance of such Tenant's obligations within thirty (30)
                  days of receipt of a billing from Landlord.

14.   ALTERATIONS. Tenant shall not make any alterations to the Premises or the
      Business Park without Landlord's prior written consent which shall not be
      unreasonably withheld. If Landlord gives its consent to such alterations,
      Landlord may post notices in accordance with the laws of the state in
      which the Premises are located. All alterations made by Tenant, whether or
      not subject to the approval of Landlord, shall be performed by Tenant and
      its contractors in a first class workmanlike manner and permits and
      inspections shall be obtained from all required governmental entities. Any
      alterations made shall remain on and be surrendered with the Premises upon
      expiration or termination of this Lease, except that Landlord may, within
      thirty (30) days before or thirty (30) days after expiration of the Term,
      elect to require Tenant to remove some or all of the alterations which
      Tenant may have made to the Premises. If Landlord so elects, Tenant shall
      at its own cost restore the Premises to the condition designated by
      Landlord in its election, before the last day of the Term or within thirty
      (30) days after notice of its election is given, whichever is later.
      Should Landlord consent in writing to Tenant's alteration of the Premises,
      Tenant shall contract with a contractor approved by Landlord for the
      construction of such alterations. shall secure all appropriate
      governmental approvals and permits, and shall complete such alterations
      with due diligence in compliance with plans and specifications approved by
      Landlord. Tenant shall pay all costs for such construction and shall keep
      the Premises free and clear of all mechanics' liens which may result from
      construction by Tenant. Notwithstanding anything in this Lease to the
      contrary:

      a.    Tenant shall not be required to remove any improvement or fixture
            installed by Tenant in, on or about the Premises pursuant to
            Tenant's repair obligation under this Lease, and Tenant shall not be
            required to remove any alterations, improvements, additions or
            utility installations for which Tenant has obtained Landlord's
            consent, unless Landlord has indicated, at the time of granting such
            consent, that such removal will be required.

      b.    Tenant shall be entitled to remove Tenant's furniture, equipment,
            trade fixtures and other personal property at the expiration of the
            term, provided Tenant repairs all damages caused by such removal.

      c.    Tenant shall be entitled to make alterations and utility
            installations in, on, under or about the Premises without consent of
            Landlord, so long as the cost of such alteration or utility
            installation does not (i) exceed the sum of $2,500; (ii) affect the
            structural or exterior portions of the Building or adversely affect
            the Building electrical, plumbing or HVAC systems; or (iii) involve
            the removal or relocation of any walls. Tenant shall, however,
            provide Landlord fifteen (15) days prior advance written notice and
            copies of a description of the alteration along with building permit
            plans(s) and specifications to enable Landlord to post any desired
            notices of non-responsibility.

15.   RELEASE AND INDEMNITY. As material consideration to Landlord, Tenant
      agrees that Landlord shall not be liable to Tenant for any damage to
      Tenant or Tenant's property from any cause, except for damages resulting
      from Landlord's gross negligence or willful misconduct, and Tenant waives
      all claims against Landlord for damage to persons or property arising for
      any reason, except for damage resulting directly from Landlord's breach of
      its express obligations under this Lease which Landlord has not cured
      within a reasonable time after written notice of such breach from Tenant.
      Tenant shall indemnify and hold Landlord harmless from all damages
      including attorneys' fees and costs arising out of any damage to any
      person or property occurring in, on or about the Premises or Tenant's use
      of the Premises or Tenant's breach of any term of this Lease.

16.   INSURANCE

      a.    Payment For Insurance. Regardless of whether the Landlord or Tenant
            is the Insuring Party, Tenant shall pay its proportionate share of
            all insurance required under this (P) 16. ("Insurance Costs") either
            directly or by reimbursement to Landlord as specified in this (P)
            16. Premiums for policy periods commencing prior to or extending
            beyond the Lease Term shall be prorated to correspond to the Lease
            Term. Payment shall be made by Tenant to Landlord within thirty (30)
            days following receipt of an invoice for any amount due.

                                      -11-
<PAGE>

      b.    Liability Insurance.

            1)    Carried by Tenant. Whether or not Tenant is the Insuring
                  Party, Tenant shall obtain and keep in force during the Term
                  of this Lease a commercial general liability policy of
                  insurance protecting Tenant and Landlord (as an additional
                  insured) against claims for bodily injury, personal injury and
                  property damage based upon, involving or arising out of the
                  ownership, use, occupancy or maintenance of the Premises and
                  all areas appurtenant thereto. Such insurance shall be on an
                  occurrence basis providing single limit coverage in an amount
                  not less than $5,000,000 per occurrence with an "Additional
                  Insured-Managers or Landlords of Premises" endorsement and
                  contain an "Amendment of the Pollution Exclusion" for damage
                  caused by heat, smoke or fumes from a hostile fire. The policy
                  shall not contain any intra-insured exclusions as between
                  insured persons or organizations, but shall include coverage
                  for liability assumed under this Lease as an "insured
                  contract" for the performance of Tenant's indemnity
                  obligations under this Lease. The limits of said insurance
                  required by this Lease or as carried by Tenant shall not,
                  however, limit the liability of Tenant nor relieve Tenant of
                  any obligation hereunder. All insurance to be carried by
                  Tenant shall be primary to and not contributory with any
                  similar insurance carried by Landlord. whose insurance shall
                  be considered excess insurance only. All insurance coverage
                  required pursuant to this (P) 16. which is to name Landlord as
                  a named insured shall also name Landlord's subsidiaries,
                  directors, agents, officers and employees as named insureds.

            2)    Carried by Landlord. In the event Landlord is the Insuring
                  Party Landlord shall also maintain liability insurance as
                  described in (P) 16.b.1), in addition to, and not in lieu of
                  the insurance required to be maintained by Tenant. In the
                  event Tenant is the Insuring Party, Landlord shall in addition
                  carry Landlord's Risk Coverage and insure the Premises on
                  Landlord's umbrella policy and Tenant shall reimburse Landlord
                  the cost thereof. Tenant shall not be named as an additional
                  insured therein under any insurance obtained by Landlord in
                  accordance with this (P) 16.b.2).

      c.    Property Insurance - Building, Improvements and Rental Value.

            1)    Building and Improvements. The Insuring Party shall obtain and
                  keep in force during the Term of this Lease a policy or
                  policies in the name of Landlord, with loss payable to
                  Landlord and to the holders of any mortgages, deeds of trust
                  or ground leases on the Business Park ("Lender(s)"), insuring
                  loss or damage to the Business Park. The amount of such
                  insurance shall be equal to the full replacement cost of the
                  Business Park, as the same shall exist from time to time, or
                  the amount required by Lender(s), but in no event more than
                  the commercially reasonable and available insurable value
                  thereof if, by reason of the unique nature or age of the
                  improvements involved, such latter amount is less than full
                  replacement cost. Such policy or policies shall insure against
                  all risks of direct physical loss or damage (including Boiler
                  and Machinery coverage and the perils of flood and earthquake)
                  (if available at a commercially reasonable cost), including
                  coverage for any additional costs resulting from debris
                  removal and reasonable amounts of coverage for the enforcement
                  of any ordinance or law regulating the reconstruction or
                  replacement of any undamaged sections of the Business Park
                  required to be demolished shall also contain an agreed
                  valuation provision in lieu of any coinsurance clause, waiver
                  of subrogation and inflation guard protection causing an
                  increase in the annual property insurance coverage amount by a
                  factor of not less than the adjusted U.S. Department of Labor
                  Consumer Price Index for All Urban Consumers for the city
                  nearest to where the Business Park is located. If such
                  insurance coverage has a deductible clause, then Tenant shall
                  be liable for its proportionate share of such deductible
                  amount not to exceed $10,000.00. Even if Landlord is the
                  Insuring Party, Tenant's personal property shall be insured by
                  Tenant under (P) 16.d. rather than by Landlord.

            2)    Rental Value. The Insuring Party shall, in addition, obtain
                  and keep in force during the term of this Lease a policy or
                  policies in the name of Landlord, with loss payable to
                  Landlord and Lender(s), insuring the loss of the full rental
                  and other charges payable by Tenant to Landlord under this
                  Lease for one (1) year (including all Real Property Taxes,
                  Insurance Costs and any scheduled Rent increases). Said
                  insurance shall provide that in the event the Lease is
                  terminated by reason of an insured loss, the period of
                  indemnity for such coverage shall be extended beyond the date
                  of the completion of repairs or replacement of the Premises,
                  to provide for one full year's loss of Rent from the date of
                  any such loss, Said insurance shall contain an agreed
                  valuation provision in lieu of any coinsurance clause, and the
                  amount of coverage shall be adjusted annually to reflect the
                  projected Rent, Real Property Taxes, Insurance Costs and other
                  expenses, if any, otherwise payable by Tenant, for the next
                  twelve (12) month period. Tenant shall be liable for any
                  deductible amount in the event of such loss.

            3)    Adjacent Premises. If the Premises are part of a larger
                  building, or if the Premises are part of a group of buildings
                  owned by Landlord which are adjacent to the Premises, the
                  Tenant shall pay for any increase in the premiums for the
                  property insurance of such building or buildings if said
                  increase is caused by Tenant's acts, omissions, use or
                  occupancy of the Premises.

            4)    Tenant's Improvements. If the Landlord is the Insuring Party,
                  the Landlord shall not be required to insure Tenant's personal
                  property and leasehold improvements unless the item in
                  question has become the property of Landlord under the terms
                  of this Lease. If Tenant is the Insuring Party,

                                      -12-
<PAGE>

                  the policy carried by Tenant under this (P) 16.c. shall insure
                  Tenant's personal property and leasehold improvements.

      d.    Tenant's Property Insurance. Subject to the requirements of (P)
            16.e., Tenant at its cost shall either by separate policy, or at
            Landlord's option, by endorsement to a policy already carried,
            maintain insurance coverage on all of Tenant's personal property and
            Tenant owned leasehold improvements in, on or about the Premises
            similar in coverage to that carried by the Insuring Party under (P)
            16.c. Such insurance shall be full replacement cost coverage with a
            deductible of not to exceed $10,000 per occurrence. The proceeds
            from any such insurance shall be used by Tenant for the replacement
            of personal property or the restoration of Tenant owned leasehold
            improvements. Tenant shall be the Insuring Party with respect to the
            insurance required by this (P) 16.d. and shall provide Landlord with
            written evidence that such insurance is in force.

      e.    Insurance Policies. If Tenant is the Insuring Party, insurance
            required per this (P) 16. shall be with companies duly licensed to
            transact business in the state where the Premises are located, and
            maintaining during the policy term a "General Policyholders Rating"
            of at least A- X, or such other minimal rating as may be required by
            Lender(s) as set forth in the most current issue of "Best's
            Insurance Guide." Tenant shall not do or permit to be done anything
            which shall invalidate the insurance policies referred to in this
            (P) 16. If Tenant is the Insuring Party, Tenant shall cause to be
            delivered to Landlord certified copies of policies of such insurance
            or certificates evidencing the existence and amounts of such
            insurance with the insureds and loss payable clauses as required by
            this Lease. No such policy shall be cancelable or subject to
            modification except after thirty (30) days prior written notice to
            Landlord. Tenant shall at least thirty (30) days prior to the
            expiration of such policies, furnish Landlord with evidence of
            renewals or "insurance binders" evidencing renewal thereof, or
            Landlord may order such insurance and charge the cost thereof to
            Tenant, which amount shall be payable by Tenant to Landlord upon
            demand. If the Insuring Party shall fail to procure and maintain the
            insurance required to be carried by the Insuring Party under this
            (P) 16., the other Party may, but shall not be required to, procure
            and maintain the same, but at Tenant's expense.

      f.    Mutual Waiver. Notwithstanding anything to the contrary contained in
            this Lease, to the extent that this release and waiver does not
            invalidate or impair their respective insurance policies, the
            parties hereto release each other and their respective agents,
            employees, officers, directors, shareholders, successors, assignees
            and subtenants from all liability for injury to any person or damage
            to any property that is caused by or results from a risk which is
            actually insured against pursuant to the provisions of this Lease
            without regard to the negligence or willful misconduct of the
            parties so released. Each party shall use its best efforts to cause
            each insurance policy it obtains to provide that the insurer
            thereunder waives all right of recovery by way of subrogation as
            required herein in connection with any injury or damage covered by
            the policy. If such insurance policy cannot be obtained with such
            waiver of subrogation, or if such waiver of subrogation is only
            available at additional cost and the party for whose benefit the
            waiver is not obtained does not pay such additional costs after
            reasonable notice, then the party obtaining such insurance shall
            promptly notify the other party of the inability to obtain insurance
            coverage with the waiver of subrogation.

17.   DAMAGE AND DESTRUCTION

      a.    Damage - Restoration Required. In the event that the Building
            containing the Premises is damaged by fire or other casualty which
            is covered under insurance pursuant to the provisions of (P) 16.
            above, Landlord shall restore such damage provided that: (i) the
            destruction of the Building containing the Premises does not exceed
            sixty percent (60%) of the then replacement value of the Building
            containing the Premises; (ii) the insurance proceeds are available
            (inclusive of any deductible amounts) to pay one hundred percent
            (100%) of the cost of restoration; and (iii) in the reasonable
            judgment of Landlord, the restoration can be completed within two
            hundred and seventy (270) days after the date of the damage or
            casualty under the laws and regulations of the state, federal,
            county and municipal authorities having jurisdiction. The pro rata
            portion of the deductible amount of any insurance coverage for
            damage to the Premises shall be paid by Tenant. If such conditions
            apply so as to require Landlord to restore such damage pursuant to
            this (P) 17.a., this Lease shall continue in full force and effect,
            unless otherwise agreed to in writing by Landlord and Tenant. Tenant
            shall be entitled to a proportionate reduction of Rent while such
            restoration takes place, such proportionate reduction to be based on
            the extent to which the damage and restoration efforts interfere
            with Tenant's business in the Premises. Tenant's right to a
            reduction of Rent hereunder shall be Tenant's sole and exclusive
            remedy in connection with any such damage.

      b.    Damage - Restoration Not Required. In the event that the Building
            containing the Premises is damaged by a fire or other casualty and
            Landlord is not required to restore such damage in accordance with
            the provisions of (P) 17.a. immediately above, Landlord shall have
            the option to either (i) repair or restore such damage, with the
            Lease continuing in full force and effect, but Rent to be
            proportionately abated as provided in (P) 17.a. above; or (ii) give
            notice to Tenant at any time within thirty (30) days after the
            occurrence of such damage terminating this Lease as of a date to be
            specified in such notice which date shall not be less than thirty
            (30) nor more than sixty (60) days after the date on which such
            notice of termination is given. In the event of the giving of such
            notice of termination, this Lease shall expire and all interest of
            Tenant in the Premises shall terminate on the date so specified in
            such notice and the Rent, reduced by any proportionate reduction in
            Rent as provided for in (P) 17.a. above, shall be paid to the date
            of such termination. Notwithstanding the foregoing, if Tenant
            delivers to Landlord the funds necessary to make up the shortage (or
            absence) in insurance proceeds and the restoration can be completed
            in a two hundred seventy (270) day period, as reasonably determined
            by Landlord, and the destruction of the

                                      -13-
<PAGE>

            Building containing the Premises does not exceed sixty percent (60%)
            of the then replacement value, Landlord shall restore the Premises
            as provided in (P) 17.a. above.

      c.    End of Term Casualty. Notwithstanding the provisions of (P) 17.a.
            and (P) 17.b. above, either Landlord or Tenant may terminate this
            Lease if the Building containing the Premises is damaged by fire or
            other casualty, Landlord's reasonably estimated cost of restoration
            of the Building containing the Premises exceeds ten percent (10%) of
            the then replacement value of the Building containing the Premise's
            and such damage or casualty occurs during the last twelve (12)
            months of the Term of this Lease (or the Term of any renewal option,
            if applicable) by giving the other notice thereof at any time within
            thirty (30) days following the occurrence of such damage or
            casualty. Such notice shall specify the date of such termination
            which date shall not be less than thirty (30) nor more than sixty
            (60) days following the date on which such notice of termination is
            given. In the event of the giving of such notice of termination,
            this Lease shall expire and all interest of Tenant in the Premises
            shall terminate on the date so specified in such notice and the Rent
            shall be paid to the date of such termination.

      d.    Termination by Tenant. In the event that the destruction to the
            Building containing the Premises cannot be restored as required
            herein under applicable laws and regulations within two hundred ten
            (210) days of the damage or casualty, notwithstanding the
            availability of insurance proceeds, Tenant shall have the right to
            terminate this Lease by giving the Landlord notice thereof within
            thirty (30) days of date of the occurrence of such casualty
            specifying the date of termination which shall not be less than
            thirty (30) days nor more than sixty (60) days following the date on
            which such notice of termination is given. In the event of the
            giving of such notice of termination, this Lease shall expire and
            all interest of Tenant in the Premises shall terminate on the date
            so specified in such notice and the Rent, reduced by any
            proportionate reduction in Rent as provided for in (P) 17a. above,
            shall be paid to the date of such termination.

      e.    Restoration. Landlord agrees that, in any case in which Landlord is
            required to, or otherwise agrees to restore the Building containing
            the Premises, Landlord shall proceed with due diligence to make all
            appropriate claims and applications for the proceeds of insurance
            and to apply for and obtain all permits necessary for the
            restoration of the Building containing the Premises. Landlord shall
            use reasonable efforts to enforce any and all provisions in any
            mortgage, deed of trust or other encumbrance on the Building
            containing the Premises requiring Landlord and Lender to permit
            insurance proceeds to be used for restoration. Landlord shall
            restore the Premises at least equal to the condition existing prior
            to the date of the damage if permitted by applicable law. Landlord
            shall not be required to restore alterations made by Tenant,
            Tenant's improvements, Tenant's trade fixtures and Tenant's personal
            property, such excluded items being the sole responsibility of
            Tenant to restore provided, however, that Landlord shall, to the
            extent of available insurance proceeds, restore Tenant Improvements
            to the Premises made by Tenant such as interior offices, lab and
            production improvements and other like improvements.

      f.    Waiver. Tenant waives the provisions of Civil Code (S) 1932(2) and
            Civil Code (S) 1933(4) with respect to any destruction of the
            Premises.

18.   CONDEMNATION

      a.    Definitions. The following definitions shall apply: (1)
            "Condemnation" means (a) the exercise of any governmental power of
            eminent domain, whether by legal proceedings or otherwise by
            condemnor, or (b) the voluntary sale or transfer by Landlord to any
            condemnor either under threat of condemnation or while legal
            proceedings for condemnation are proceeding; (2) "Date of Taking"
            means the date the condemnor has right to possession of the property
            being condemned; (3) "Award" means all compensation, sums or
            anything of value awarded, paid or received on a total or partial
            Condemnation; and (4) "Condemnor" means any public or quasi-public
            authority, or. private corporation or individual, having power of
            Condemnation.

      b.    Obligations to be Governed by Lease. If during the Term of the Lease
            there is any taking of all or any part of the Building containing
            the Premises, the rights and obligations of the parties shall be
            determined strictly pursuant to this Lease. Each party waives the
            provisions of Code of Civil Procedure (S) 1265.130 allowing either
            party to petition the Superior Court to terminate this Lease in the
            event of a partial condemnation of the Premises.

      c     Total or Partial Taking. If the Building containing the Premises are
            totally taken by Condemnation, this Lease shall terminate on the
            Date of Taking. If any portion of the Building containing the
            Premises is taken by Condemnation, this Lease shall remain in
            effect, except that Tenant can elect to terminate this Lease if the
            remaining portion of the Premises is rendered unsuitable for
            Tenant's continued use of the Premises. If Tenant elects to
            terminate this Lease, Tenant must exercise its right to terminate by
            giving notice to Landlord within thirty (30) days after the nature
            and extent of the Condemnation have been finally determined. If
            Tenant elects to terminate this Lease, Tenant shall also notify
            Landlord of the date of termination, which date shall not be earlier
            than thirty (30) days nor later than ninety (90) days after Tenant
            has notified Landlord of its election to terminate; except that this
            Lease shall terminate on the Date of Taking if the Date of Taking
            falls on a date before the date of termination as designated by
            Tenant. If any portion of the Premises is taken by Condemnation and
            this Lease remains in full force and effect, on the Date of Taking
            the Base Rent shall be reduced by an amount in the same ratio as the
            total number of square feet in the Premises taken bears to the total
            number of square feet in the Premises immediately before the Date of
            Taking. Any Award for the taking of all or any part of the Premises
            under the power of eminent domain or any payment made under threat
            of the exercise of such power shall be the property of

                                      -14-
<PAGE>

            Landlord, whether such Award shall be made as compensation for
            diminution in value of the leasehold or for the taking of the fee,
            or as severance damages; provided, however, that Tenant shall be
            entitled to any compensation separately awarded to Tenant for
            Tenant's relocation expenses and/or loss of Tenant's trade fixtures.

19.   ASSIGNMENT OR SUBLEASE

      a.    Tenant shall not assign or encumber its interest in this Lease or
            the Premises or sublease all or any part of the Premises or allow
            any other person or entity (except Tenant's authorized
            representatives, employees, invitees or guests) to occupy or use all
            or any part of the Premises without first obtaining Landlord's
            consent, which consent shall not be unreasonably withheld. Any
            assignment, encumbrance or sublease without Landlord's prior written
            consent shall be voidable and at Landlord's election, shall
            constitute a default. If Tenant is a partnership, a withdrawal or
            change, voluntary, involuntary or by operation of law of any
            partner, or the dissolution of the partnership, shall be deemed a
            voluntary assignment. If Tenant consists of more than one person, a
            purported assignment, voluntary or involuntary or by operation of
            law from one person to the other shall be deemed a voluntary
            assignment. If Tenant is a corporation, any dissolution, merger,
            consolidation or other reorganization of Tenant, or sale or other
            transfer of a controlling percentage of the capital stock of Tenant,
            or the sale of at least fifty percent (50%) of the value of the
            assets of Tenant shall be deemed a voluntary assignment.
            Notwithstanding the sentence immediately above, if the Tenant is a
            corporation, the Tenant shall be entitled to assign this Lease
            without Landlord's prior written consent to: (i) a successor
            corporation related to Tenant by merger consolidation or
            non-bankruptcy reorganization, provided that the surviving
            Corporation in connection with any such assignment shall have a
            minimum net worth as of the date of the assignment at least equal to
            that of Tenant immediately prior to completion of the subject
            merger, consolidation or reorganization, (ii) a purchaser of
            substantially all of Tenant's assets, provided that immediately
            following such purchase, such purchaser shall have a net worth at
            least equal to that of Tenant immediately prior to the completion of
            the subject purchase, or (iii) a sale or transfer of a controlling
            percentage of the capital stock of Tenant if (1) such sale or
            transfer occurs in direct connection with any bona fide financing
            for the benefit of Tenant or (2) at such time Tenant becomes a
            publicly traded corporation (a transferee described in (i), (ii) or
            (iii) shall be referred to as a "Permitted Transferee"). In
            connection with any assignment as described in the sentence
            immediately above, Landlord shall be entitled to require an increase
            in the Security Deposit to the extent that such increase should be
            commercially reasonable in Landlord's reasonable discretion given
            the financial condition of Tenant and the assignee following such
            event. Tenant shall give Landlord at least sixty (60) days prior
            written notice of any intended transfer to a Permitted Transferee
            and in connection with such transfer shall provide to Landlord
            copies of any documents or other information as Landlord may
            reasonably request. Unless otherwise expressly agreed in writing by
            Landlord, no assignment shall relieve Tenant of any of its
            obligations pursuant to this Lease. All Rent received by Tenant from
            its subtenants in excess of the Rent payable by Tenant to Landlord
            under this Lease applicable to the portion of the Premises
            subleased, after deducting therefrom the commercially reasonable
            brokerage commissions, moving allowance to subtenants, Tenant
            Improvements made at request of subtenants and attorneys' fees
            incurred by Tenant in negotiating and documenting the sublease,
            shall be deemed "Bonus Rent" and 75% of the Bonus Rent shall be
            promptly paid to Landlord or, as the case may be, 75% of any sums
            (determined in the same manner as Bonus Rent) to be paid by an
            assignee to Tenant in consideration of the assignment of this Lease
            shall be promptly paid to Landlord. There shall be no deemed "Bonus
            Rent" in the event of a Permitted Transfer. If Tenant requests
            Landlord to consent to a proposed assignment or subletting, Tenant
            shall pay to Landlord, whether or not consent is ultimately given,
            an amount equal to Landlord's reasonable attorneys' fees and costs
            incurred in connection with such request. Each request for consent
            to an assignment or subletting shall be in writing, and shall be
            accompanied by information as may be relevant to Landlord's
            determination as to the financial and operational responsibility and
            stability of the proposed assignee or sublessee and the
            appropriateness of the proposed use by such assignee or sublessee.
            Such information shall include a summary of the proposed use of, and
            any proposed modifications to, the Premises. Tenant shall provide
            Landlord with such other or additional information and/or
            documentation as may reasonably be requested by Landlord. Tenant
            shall, upon completion of any assignment or subletting of all or any
            portion of the Premises, immediately and irrevocably assign to
            Landlord as security for Tenant's obligations under the Lease. all
            Rent from any such subletting or assignment. Upon a default by
            Tenant, Landlord, as assignee and attorney in fact for Tenant, shall
            have the right to collect all rent and other revenues collectable
            pursuant to any such sublet or assignment and apply such rent and
            other revenues towards Tenant's obligations under the Lease.

      b.    No interest of Tenant in this Lease shall be assignable by
            involuntary assignment through operation of law (including without
            limitation the transfer of this Lease by testacy or intestacy). Each
            of the following acts shall be considered an involuntary assignment:
            (a) if Tenant is or becomes bankrupt or insolvent, makes 1 an
            assignment for the benefit of creditors, or institutes proceedings
            under the Bankruptcy Act in which Tenant is the bankrupt; or if
            Tenant is a partnership or consists of more than one person or
            entity, if any partner of the partnership or other person or entity
            is or becomes bankrupt or insolvent, or makes an assignment for the
            benefit of creditors; or (b) if a writ of attachment or execution is
            levied on this Lease: or (c) if in any proceeding or action to which
            Tenant is a party, a receiver is appointed with authority to take
            possession of the Premises. An involuntary assignment shall
            constitute a default by Tenant and Landlord shall have the right to
            elect to terminate this Lease, in which case this Lease shall not be
            treated as an asset of Tenant.

                                     -15-
<PAGE>

      c.    Notwithstanding any other provision of this Lease to the contrary,
            in any event where Landlord's consent is required for (i) assignment
            or (ii) sublease of more than 50% of the Premises, Landlord may, at
            its option, elect to terminate the Lease instead of approving the
            requested assignment or sublease. Should Landlord so elect to
            terminate this Lease, all of the obligations of the parties
            thereunder shall terminate on the later of sixty (60) days following
            Landlord's notice to Tenant of its election hereunder, or the
            effective date of the proposed assignment or subletting sought by
            the Tenant, but in no event later than one hundred twenty (120) days
            following the date of Landlord's election under this (P) 19.c. At
            the time of termination, all obligations of both parties hereunder
            shall terminate as to obligations thereafter accruing except as
            otherwise expressly provided in this Lease.

20.   DEFAULT. The occurrence of any of the following shall constitute a default
      by Tenant: (a) a failure of Tenant to pay Rent within ten (10) days of its
      due date; (b) abandonment of the Premises; or (c) failure to timely
      perform any other provision of this Lease where such failure continues for
      a period in excess of thirty days following notice of such failure,
      provided however, that if the nature of such failure is such that it
      cannot reasonably be cured within thirty days, then Tenant shall not be in
      default if Tenant commences to cure such failure within thirty days and
      thereafter diligently prosecutes the cure to completion. Tenant shall give
      written notice to Landlord of any default by Landlord of its obligations
      pursuant to this Lease asserted by Tenant (with a copy of such notice to
      any lender ("Lender") against the Premises). Landlord and Landlord's
      Lender shall be afforded a reasonable opportunity to cure any claimed
      default by Landlord and Landlord shall not be considered in default so
      long as Landlord (or Landlord's Lender) commences such cure within a
      reasonable period of time and thereafter, continues to attempt to complete
      such cure. Landlord, from time to time, shall provide Tenant with the name
      and address of its Lender.

21.   LANDLORD'S REMEDIES. Landlord shall have the following remedies if Tenant
      is in default. (These remedies are not exclusive; they are cumulative and
      in addition to any remedies now or later allowed by law):

      a.    Landlord may continue this Lease in full force and effect, and this
            Lease will continue in effect so long as Landlord does not terminate
            Tenant's right to possession, and Landlord shall have the right to
            collect Rent when due. During the period Tenant is in default,
            Landlord can enter the Premises and relet the Premises, or any part
            of the Premises, to third parties for Tenant's account. Tenant shall
            be liable immediately to Landlord for all costs Landlord reasonably
            incurs in reletting the Premises, including without limitation,
            brokers' commissions, reasonable expenses of remodeling the Premises
            required by the reletting, and like costs. Reletting can be for a
            period shorter or longer than the remaining Term of this Lease.
            Tenant shall pay to Landlord the Rent due under this Lease on the
            dates the Rent is due, less the Rent Landlord receives from any
            reletting. No act by Landlord allowed by this (P) 21.a. shall
            terminate this Lease unless Landlord notifies Tenant in writing that
            Landlord elects to terminate this Lease After Tenant's default and
            for so long as Landlord does not terminate Tenant's right to
            possession of the Premises, if Tenant obtains Landlord's consent,
            Tenant shall have the right to assign or sublet its interest in this
            Lease, but Tenant shall not be released from liability. Landlord's
            consent to such a proposed assignment or subletting shall not be
            unreasonably withheld. If Landlord elects to relet the Premises as
            provided in this (P) 21.a., Rent that Landlord receives from
            reletting shall be applied to the payment of: first, any
            indebtedness from Tenant to Landlord other than Rent due from
            Tenant; second, all costs, including for maintenance incurred by
            Landlord in reletting; and third, Rent due and unpaid under this
            Lease. After deducting the payments referred to in this (P) 21.a.,
            any sum remaining from the Rent Landlord receives from reletting
            shall be held by Landlord and applied in payment of future Rent as
            Rent becomes due under this Lease. In no event shall Tenant be
            entitled to any excess Rent received by Landlord. If, on the date
            Rent is due under this Lease, the Rent received from the reletting
            is less than the Rent due on that date, Tenant shall pay to
            Landlord. in addition to the remaining Rent due, all costs including
            for maintenance Landlord incurred in reletting that remain after
            applying the Rent received from the reletting as provided In this
            (P) 21.a.; and

      b.    Landlord may terminate Tenant's right to possession of the Premises
            at any time. No act by Landlord other than giving express written
            notice thereof to Tenant shall terminate this Lease. Acts of
            maintenance, efforts to relet the Premises, or the appointment of a
            receiver on Landlord's initiative to protect Landlord's interest
            under this Lease shall not constitute a termination of Tenant's
            right to possession. Upon termination of Tenant's right to
            possession, Landlord has the right to recover from Tenant: (1) the
            Worth of the unpaid Rent that had been earned at the time of
            termination of Tenant's right to possession: (2) the Worth of the
            amount by which the unpaid Rent that would have been earned after
            the date of termination until the time of award exceeds the amount
            of the loss of Rent that Tenant proves could have been reasonably
            avoided; (3) the Worth of the amount of the unpaid Rent that would
            have been earned after the award throughout the remaining Term of
            the Lease to the extent such unpaid Rent exceeds the amount of the
            loss of Rent that Tenant proves could have been reasonably avoided;
            and (4) any other amount including but not limited to, reasonable
            expenses incurred to relet the Premises, court costs, attorneys'
            fees and collection costs necessary to compensate Landlord for all
            detriment proximately caused by Tenant's default. The "Worth", as
            used above in (1) and (2) in this (P) 21.b. is to be computed by
            allowing interest at the lesser of 18 percent per annum or the
            maximum legal interest rate permitted by law. The "Worth", as used
            above in (3) in this (P) 21.b., is to be computed by discounting the
            amount at the discount rate of the Federal Reserve Bank of San
            Francisco at the time of the award, plus one percent (1%)

22.   ENTRY OF PREMISES. Landlord and/or its authorized representatives shall
      have the right to enter the Premises at all reasonable times for any of
      the following purposes: (a) to determine whether the Premises are in good
      condition and whether Tenant is complying with its obligations under this
      Lease; (b) to do any necessary maintenance and to make any restoration to
      the Premises that Landlord has the right or obligation to perform: (c) to
      post "for sale" signs at any time during the Term, or to post "for rent"
      or "for lease" signs during the last one

                                     -16-
<PAGE>

      hundred eighty (180) days of the Term or during any period while Tenant is
      in default; (d) to show the Premises to prospective brokers, agents,
      buyers, tenants or persons interested in leasing or purchasing the
      Premises. at any time during the Term; or (e) to repair, maintain or
      improve the Premises and to erect scaffolding and protective barricades
      around and about the Premises but not so as to prevent entry to the
      Premises or to unreasonably interfere with Tenant's use of the Premises
      and to do any other act or thing necessary for the safety or preservation
      of the Premises. Landlord shall not be liable in any manner for any
      inconvenience, disturbance loss of business, nuisance or other damage
      arising out of Landlord's entry onto the Premises as provided in this (P)
      22. Tenant shall not be entitled to an abatement or reduction of Rent if
      Landlord exercises any rights reserved in this (P) 22. Landlord shall
      conduct its activities on the Premises as provided herein in a
      commercially reasonable manner that will lessen the inconvenience,
      annoyance or disturbance to Tenant. Notwithstanding the provisions of this
      (P) 22., Landlord shall provide Tenant with at least 24 hours prior actual
      notice before entering the Premises except that in the event of an
      emergency, the determination of which shall require Landlord to be
      reasonable. Landlord shall use its best efforts to provide Tenant with
      notice reasonable in such situation prior to performing any affirmative
      duty or obligation of Tenant. In the event of any entry by Landlord onto
      the Premises, Landlord shall use its best efforts not to interfere with
      the conduct of Tenant's business.

23.   SUBORDINATION

      a.    Automatic Subordination. Without the necessity of any additional
            document being executed by Tenant for the purpose of effecting a
            subordination, and at the election of Landlord or Landlord's Lender,
            this Lease shall be subject and subordinate at all times to (i) all
            ground leases or underlying leases which may now exist or hereafter
            be executed affecting the Premises, (ii) the lien of any mortgage or
            deed of trust which may now exist or hereafter be executed affecting
            the Premises, and (iii) the lien of any mortgage or deed of trust
            which may hereafter be executed in any amount for which the
            Premises, ground leases or underlying leases, or Landlord's interest
            or estate in any of said items is specified as security. In the
            event that any ground lease or underlying lease terminates for any
            reason or any mortgage or deed of trust is foreclosed or a
            conveyance in lieu of foreclosure is made for any reason, Tenant
            shall, notwithstanding any subordination, attorn to and become the
            Tenant of the successor in interest (including without limitation to
            Lender) to Landlord ("Successor"). In connection with any such
            termination of a ground lease or underlying lease or any foreclosure
            or conveyance in lieu of foreclosure made in connection with any
            mortgage or deed of trust, then so long as Tenant is not in default
            pursuant to this Lease, Tenant shall not be disturbed in its
            possession of the Premises or in the enjoyment of its rights
            pursuant to this Lease during the Term of this Lease or any
            extension or renewal thereof. Notwithstanding any subordination of
            this Lease to the lien of any mortgage or deed of trust, the Lender,
            at any time shall be entitled to subordinate the lien of its
            mortgage or deed of trust to this Lease by filing a notice of
            subordination in the County in which the Premises are located, and
            Lender shall agree in connection with any such filing, that Tenant
            shall not be disturbed in its possession of the Premises so long as
            Tenant is not in default pursuant to this Lease. In connection with
            any such filing, Tenant shall be obligated to attorn to and to
            become a Tenant of any Successor.

      b.    Additional Subordination. From time to time at the request of
            Landlord, Tenant covenants and agrees to execute and deliver within
            ten (10) days following the date of written request from Landlord,
            documents evidencing the priority or subordination of this Lease
            with respect to any ground lease or underlying lease or the lien of
            any mortgage or deed of trust in connection with the Premises. Any
            and all such documents shall be in such form as is reasonably
            acceptable to the Lender(s). Any subordination agreement so
            requested by Landlord shall provide for Tenant to attorn to the
            Successor and shall further provide that Tenant shall not be
            disturbed in its possession of the Premises or in the enjoyment of
            its rights pursuant to this Lease so long as Tenant is not in
            default with respect to its obligations pursuant to the Lease. Any
            such Subordination, Non-disturbance and Attornment Agreement shall
            be recorded in the official records of the office of the County
            Recorder in the County in which the Premises is located.

      c.    Notice from Lender. Tenant shall be entitled to rely upon any notice
            given by a Lender in connection with the Premises requesting that
            Tenant make all future Rent payments to such Lender, and Tenant
            shall not be liable to Landlord for any payment made to such Lender
            in accordance with such notice. Notwithstanding any provision to the
            contrary of this Lease, a Successor shall not be (i) obligated to
            recognize the payment of Rent for a period of more than one month in
            advance; (ii) responsible for liabilities accrued pursuant to this
            Lease prior to the date ("Succession Date" ) upon which the
            Successor becomes the "Landlord" hereunder; (iii) responsible to
            cure defaults of the Landlord pursuant to this Lease existing as of
            the Succession Date, except for defaults of a continuing nature of
            which Successor received notice (as provided in Paragraph 20) and
            in. respect of which Tenant afforded Successor a reasonable cure
            period following such notice; (iv) responsible for any Security
            Deposit delivered by Tenant pursuant to this Lease not actually
            received by the Successor; or (v) bound by any execution,
            modification, termination or extension of this Lease or any grant of
            a purchase option or right of first refusal or any other action
            taken by the Landlord pursuant to this Lease, except in accordance
            with the provisions of that certain Absolute Assignment of Leases
            and Rents executed by Landlord in favor of Lender.

24.   ESTOPPEL CERTIFICATE; TENANT FINANCIAL STATEMENTS. Tenant, at any time and
      from time to time, upon not less than ten (10) days written notice from
      Landlord, will execute, acknowledge and deliver to Landlord and, at
      Landlord's request, to any existing or prospective purchaser, ground
      lessor or mortgagee of any part of the Premises, a certificate of Tenant
      stating: (a) that Tenant has accepted the Premises, (or, if Tenant has not
      done so, Tenant has not accepted the Premises and specifying the reasons
      therefor); (b) the Commencement and Expiration Dates of this Lease; (c)
      that this Lease is unmodified and in full force and effect (or, if there
      have been modifications, that same is in full force and effect as modified
      and stating the modifications); (d) whether or not to

                                     -17-
<PAGE>

      the best of Tenant's knowledge there are then existing any defenses
      against the enforcement of any of the obligations of Tenant under this
      Lease (and, if so, specifying same); (e) whether or not to the best of
      Tenant's knowledge there are then existing any defaults by Landlord in the
      performance of its obligations under this Lease (and, if so, specifying
      same); (f) the dates, if any, to which the Rent and other charges under
      this Lease have been paid; (g) whether or not there are Rent increases
      during the Lease Term and if so the amount of same; (h) whether or not the
      Lease contains any options or rights of first offer or first refusal; (i)
      the amount of any Security Deposit or other sums due Tenant; (j) the
      current notice address for Tenant; and (k) any other information that may
      reasonably be required by any of such persons. It is intended that any
      such certificate of Tenant delivered pursuant to this (P) 24. may be
      relied upon by Landlord and any existing or prospective purchaser, ground
      lessor or mortgagee of the Building containing the Premises. Tenant
      agrees, at any time upon request by Landlord, to deliver to Landlord the
      most recent quarterly current financial statements of Tenant with an
      opinion from a certified public accountant, if available, including a
      balance sheet and profit and loss statement for the most recent prior
      three years, all prepared in accordance with generally accepted accounting
      principles consistently applied; Landlord agrees to hold such financial
      statements confidential and to share them only with prospective lenders
      and purchasers of the Business Park. Other than for prospective lenders
      and purchasers, Landlord shall not request financial statements more often
      than twice in any calendar year.

25.   WAIVER. No delay or omission in the exercise of any right or remedy by
      Landlord shall impair such right or remedy or be construed as a waiver. No
      act or conduct of Landlord, including without limitation, acceptance of
      the keys to the Premises, shall constitute an acceptance of the surrender
      of the Premises by Tenant before the expiration of the Term. Only written
      notice from Landlord to Tenant shall constitute acceptance of the
      surrender of the Premises and accomplish termination of the Lease.
      Landlord's consent to or approval of any act by Tenant requiring
      Landlord's consent or approval shall not be deemed to waive or render
      unnecessary Landlord's consent to or approval of any subsequent act by
      Tenant. Any waiver by Landlord of any Default must be in writing and shall
      not be a waiver of any other Default concerning the same or any other
      provision of the Lease.

26.   SURRENDER OF PREMISES. Upon expiration of the Term, Tenant shall surrender
      to Landlord the Premises and all tenant improvements and alterations in
      the same condition as existed at the commencement date of the Old Lease
      (as defined below), except for ordinary wear and tear and alterations
      which Tenant has the right or is obligated to remove under the provisions
      of (P) 14. herein. Tenant shall remove all personal property including,
      without limitation, all wallpaper, paneling and other decorative
      improvements or fixtures and shall perform all restoration made necessary
      by the removal of any alterations or Tenant's personal property before the
      expiration of the Term, including, for example, restoring all wall
      surfaces to their condition as of the commencement date of the Old Lease.
      Landlord can elect to retain or dispose of in any manner Tenant's personal
      property not removed from the Premises by Tenant prior to the expiration
      of the Term. Tenant waives all claims against Landlord for any damage to
      Tenant resulting from Landlord's retention or disposition of Tenant's
      personal property. Tenant shall be liable to Landlord for Landlord's cost
      for storage, removal and disposal of Tenant's personal property.

27.   HOLDOVER. If Tenant with Landlord's consent remains in possession of the
      Premises after expiration of the Term or after the date in any notice
      given by Landlord to Tenant terminating this Lease pursuant to (P) 17.
      or (P) 18., such possession by Tenant shall be deemed to be a month to
      month tenancy cancelable by either party on thirty (30) days written
      notice given at any time by either party and all provisions of this Lease,
      except those pertaining to Term, renewal options and Base Rent, shall
      apply and Tenant shall thereafter pay monthly Base Rent computed on a per-
      month basis, for each month or part thereof (without reduction for any
      partial month) that Tenant remains in possession, in an amount equal to
      one hundred fifty percent (150%) of the Base Rent that was in effect for
      the last full calendar month immediately preceding expiration of the Term.

      If Tenant holds over after the expiration or earlier termination of the
      Term hereof, without the consent of Landlord, Tenant shall become a Tenant
      at sufferance only with a continuing obligation to pay Rent provided that
      the Base Rent shall be one hundred fifty percent (150%) of the Base Rent
      that was in effect for the last full calendar month immediately preceding
      expiration of the Term for the first thirty (30) days of such holdover,
      and two hundred percent (200%) of such Base Rent thereafter during the
      pendency of such holdover. Acceptance by Landlord of Rent after expiration
      or earlier termination of the Term shall not constitute a consent to a
      holdover hereunder or result in a renewal. The foregoing provisions of
      this (P) 27 are in addition to and do not affect Landlord's right of
      re-entry or any rights of Landlord hereunder or as otherwise provided by
      law. If Tenant fails to surrender the Premises upon the expiration of this
      Lease despite demand to do so by Landlord, Tenant shall indemnify and hold
      Landlord harmless from all loss or liability arising out of such failure,
      including without limitation, any claim made by any succeeding tenant
      founded on or resulting from such failure to surrender. No provision of
      this (P) 27 shall be construed as implied consent by Landlord to any
      holding over by Tenant. Landlord expressly reserves the right to require
      Tenant to surrender possession of the Premises to Landlord as provided in
      this Lease upon expiration or other termination of this Lease. The
      provisions of this (P) 27 shall not be considered to limit or constitute a
      waiver of any other rights or remedies of Landlord provided in this Lease
      or at law.

28.   NOTICES. All notices, demands, or other communications required or
      contemplated under this Lease, including any notice delivered to Tenant by
      the Lender, shall be in writing and shall be deemed to have been duly
      given 48 hours from the time of mailing if mailed by registered or
      certified mail, return receipt requested, postage prepaid, or 24 hours
      from the time of shipping by overnight carrier, or the actual time of
      delivery if delivered by personal service to the parties at the addresses
      specified in (P) 1. Either Tenant or Landlord may change the address to
      which notices are to be given to such party hereunder by giving written
      notice of such change of address to the other in accordance with the
      notice provisions hereof.

                                     -18-
<PAGE>

29.   COMMENCEMENT DATE:

      a.    Temporary Premises: The term of the Lease as to the Temporary
            Premises ("Temporary Premises Commencement Date") will commence upon
            Landlord's substantial completion of Landlord's Tenant Improvements,
            as evidenced by a temporary or permanent certificate of occupancy if
            such is issued by the city of Mountain View, and delivery of
            possession of the Premises to Tenant. Landlord will attempt to give
            Tenant seven (7) days advance notice of the Commencement Date.

      b.    Original Premises: The term of the Lease as to the Original Premises
            ("Original Premises Commencement Date") will commence on the same
            day as the Temporary Premises Commencement Date. Effective with the
            Original Premises Commencement Date, that certain lease (the "Old
            Lease") dated 2/23/98 by and between Limar Realty Corp. #17 as
            successor in interest to 2400 Charleston Associates, LLC, and
            Docent, Inc. for 2444 Charleston Road, Mountain View, California is
            terminated except for any obligations and liabilities which are
            accrued but unsatisfied as of said date. Upon the written request of
            Landlord, the parties hereto agree to execute a separate Lease
            Termination Agreement to further document the termination of the Old
            Lease.

      c.    Expansion Premises: The term of the Lease as to the Expansion
            Premises ("Expansion Premises Commencement Date") will commence on
            the day following substantial vacation of the Expansion Premises by
            the existing tenant (Optimal) and delivery of possession of the
            Premises to Tenant. Landlord will attempt to give Tenant seven (7)
            days advance notice of the Commencement Date. If the Expansion
            Premises is not delivered by August 1, 2000, then the Initial Base
            Rental for the Temporary Premises shall be reduced to $25,200 per
            month effective August 1, 2000.

30.   EXPIRATION DATE:

      a.    Temporary Premises: The term of the Lease as to the Temporary
            Premises will expire on the last day of the calendar month in which
            the space is fully vacated by Tenant in conformity with the
            provisions of (P) 26. above.

      b.    Original Premises: The term of the Lease as to the Original Premises
            will expire on May 31, 2005

      c.    Expansion Premises: The term of the Lease as to the Expansion
            Premises will expire on May 31, 2005.

31.   TENANT'S SHARE OF BUILDING. Tenant's Share of Building shall at any given
      time be the sum of the Tenant Share of Building for any and all premises
      for which the Lease for the Premises is in effect using the percentages
      given below.

<TABLE>
<CAPTION>
                                 Building Share                             Business Park Share
                                 --------------                             -------------------
      <S>   <C>                  <C>                                        <C>
      a.    Temporary Premises:  100.00% (12,000 sq. ft. / 12,000 sq. ft.)  10.08% (12,000 sq. ft. / 119,080 sq. ft.)

      b.    Original Premises:   46.92% (12,200 sq. ft. / 26,000 sq. ft.)   10.25% (12,200 sq. ft. / 119,080 sq. ft.)

      c.    Expansion Premises:  53.08% (13,800 sq. ft. / 26,000 sq. ft.)   11.59% (13,800 sq. ft. / 119,080 sq. ft.)
</TABLE>

32.   TENANT'S NUMBER OF NON-RESERVED PARKING SPACES. Tenant's Share of Parking
      Spaces shall at any given time be the sum of the parking allowed below as
      to that portion of the Premises for which the Lease is in effect:

      a.    Temporary Premises:  46 spaces.

      b.    Original Premises:   42 spaces.

      c.    Expansion Premises:  53 spaces.

33.   INITIAL BASE RENT. The initial monthly base rent for each respective
      portion of the Premises is as follows:

      a.    Temporary Premises = $30,000.00 per month.

      b.    Original Premises =  $23,427.66 per month.

      c.    Expansion Premises = $28,980.00 per month.

34.   BASE RENT ADJUSTMENT.

      a.    Temporary Premises: NONE, unless the Temporary Premises Expiration
            Date is on or after 1/1/2001 in which case, effective 1/1/2001 and
            each January 1 thereafter, the monthly Base Rent for the Temporary
            Premises will increase by four percent (4%).

                                     -19-
<PAGE>

      b.    Original Premises:

            1)    As to the following adjustment dates: 4/1/00, 4/1/01, 4/1/02
                  and 4/1/03, the cost of living provisions of (P) 4.b. apply
                  using the CPI Index for the CMSA of San Francisco-Oakland and
                  the annual floor limit ("Floor Limit") shall be an increase of
                  two percent (2%) and the annual ceiling limit ("Ceiling
                  Limit") shall be an increase of five percent (5%).

            2)    The Base Rent for the Original Premises shall be further
                  adjusted as follows:

                          Effective 10/1/03: $28,818.84 per month (12,200
                          rentable square feet x $2.3622)

                          Effective 1/1/04: $29,971.74 per month (12,200
                          rentable square feet x $2.4567)

                          Effective 1/1/05: $31,171.00 per month (12,200
                          rentable square feet x $2.5550)

      c.    Expansion Premises: The Base Rent for the Expansion Premises shall
            be adjusted as follows:

                          Effective 1/1/01: $30,139.20 per month (13,800
                          rentable square feet @ $2.1840)

                          Effective 1/1/02: $31,345.32 per month (13,800
                          rentable square feet @ $2.2714)

                          Effective 1/1/03: $32,598.36 per month (13,800
                          rentable square feet @ $2.3622)

                          Effective 1/1/04: $33,902.46 per month (13,800
                          rentable square feet @ $2.4567)

                          Effective 1/1/05: $35,259.00 per month (13,800
                          rentable square feet @ $2.5550)

35.   TENANT IMPROVEMENTS.

      a.    Temporary Premises: Landlord, at Landlord's sole cost and expense,
            will demolish the existing tenant improvements as necessary and
            provide and install new building standard tenant improvements for an
            "open office" layout--namely, at least 6 private offices (which may
            include 1 or more conference rooms). an equipment room to house
            servers and telephone switching equipment, the existing
            configuration of bathrooms, dropped ceiling and building standard
            lighting, new floor covering, HVAC and sprinklers distributed in an
            "open office" configuration and new paint throughout the Temporary
            Premises ("Landlord's Tenant Improvements"). If Tenant requires
            additional tenant improvements ("Tenant's Tenant Improvements"),
            Landlord will provide and install the Tenant's Tenant Improvements.
            subject to Landlord's approval of the scope of work, at Tenant's
            sole cost and expense. Tenant shall be required to remove all or
            part of Tenant's Tenant Improvements by the Temporary Premises
            Expiration Date as specified by Landlord at the time of approval of
            Tenant's Tenant Improvements.

      b.    Original Premises: Except as otherwise provided herein, the existing
            Docent Space will be leased to Tenant in its "as is" condition
            except that upon request by Tenant within the six (6) month period
            preceding October 1, 2003, Landlord at its cost shall paint the
            interior of the Premises and shall shampoo the carpets.

      c.    Expansion Premises: Except as otherwise provided herein, Landlord
            shall deliver the Premises in its "as is" condition as of the
            Expansion Premises Commencement Date except that Landlord at its
            sole cost shall provide and install certain work in conjunction with
            making the building into that of a single tenant - namely, the
            partial removal of the present demising wall and in conjunction with
            the removal of said wall. any needed paint touch-up and adjustments
            to the HVAC, lighting and fire sprinkler systems Landlord shall be
            responsible for assuring that the prior tenant in the Expansion
            Premises leaves the Expansion Premises in broom clean condition with
            all damage repaired except for normal wear and tear.

36.   SECURITY DEPOSITS.

      a.    Security Deposits Required: The total Security Deposit required to
            be held by Landlord at any given time is the sum of Security
            Deposits for each portion of the Premises for which the Lease is
            then in effect, subject to the reduction provision in (P) 36.b below
            and the general provisions of (P) 6.

            1)    Temporary Premises Security Deposit equals $90,000.00.

            2)    Original Premises Security Deposit equals $67,710.00 (said
                  amount is held by Landlord per (P) 2.13 of the Old Lease).

            3)    Expansion Premises Security Deposit equals $86,940.00.

      b.    Security Deposit Reduction:

            1)    Subject to the general provisions of P. 6. and provided that
                  Tenant has not been in default under this Lease beyond any
                  applicable cure period, the Security Deposit on the Temporary
                  Premises shall be returned within five (5) business days of
                  the Temporary Premises Expiration Date.

                                     -20-
<PAGE>

            2)    Subject to the general provisions of P. 6. and provided that
                  Tenant has not been in default under this Lease beyond any
                  applicable cure period, the Security Deposit on the Original
                  Premises and Expansion Premises combined shall be subject to
                  reduction as follows:

                  a)  Reduction to two (2) months Rent, upon Tenant achieving a
                      public equity market capitalization of at least $150
                      million.

                  b)  Reduction to one (1) months Rent, upon Tenant achieving a
                      public equity market capitalization of at least $400
                      million,

37.   MISCELLANEOUS PROVISIONS.

      a.    Time of Essence, Time is of the essence of each provision of this
            Lease,

      b.    Successor. This Lease shall be binding on and inure to the benefit
            of the parties and their successors, except as provided (P) 19.

      c.    Landlord's Consent. Any consent required by Landlord under this
            Lease must be granted in writing and may be withheld or conditioned
            by Landlord in its sole and absolute discretion unless otherwise
            provided.

      d.    Personal Rights. Notwithstanding any other provision(s) of this
            Lease to the contrary, any provisions of this Lease providing for
            the renewal, extension or early termination of the Lease and/or for
            the expansion of the Premises (to include without limitation rights
            to negotiate, rights of first refusal, etc.) shall be (i) personal
            to the original Tenant and shall not be assignable or otherwise
            transferable except to a Permitted Transferee (either voluntarily or
            involuntarily) to any third party for any reason whatsoever, and
            (ii) conditioned upon Tenant not then being in default under this
            Lease.

      e.    Year 2000. Notwithstanding any covenant or provision contained in
            this Lease to the contrary, Landlord shall have no liability or
            responsibility whatsoever to Tenant for (i) any disruption or
            interruption in Tenant's business, (ii) any disruption or
            interruption in Tenant's use or possession of the Premises, or (iii)
            any other damage or consequence suffered or experienced by Tenant,
            arising from or relating in any way to the malfunction, shut down or
            other abnormal behavior of any computer or computer controlled
            system which provides utilities or services to the Premises, or
            controls any systems serving the Premises (whether such computer is
            within the control of Landlord or otherwise) resulting from the
            inability or failure of any such computer or computer controlled
            system to recognize the year 2000, and distinguish said year from
            the year 1900 (sometimes referred to as the "Y2K problem", or the
            "failure to be year 2000 compliant").

      f.    Commissions. Each party represents that it has not had dealings with
            any real estate broker, finder or other person with respect to this
            Lease in any manner, except for the Broker(s) identified (P) 1.,
            who shall be compensated by Landlord in accordance with the separate
            agreement between Landlord and the Broker(s).

      g.    Other Charges; Legal Fees. If Landlord through no fault of its own
            becomes a party to any litigation concerning this Lease or the
            Premises by reason of any act or omission of Tenant or Tenant's
            authorized representatives, Tenant shall be liable to Landlord for
            reasonable attorneys' fees and court costs incurred by Landlord in
            the litigation. Should the court render a decision which is
            thereafter appealed by any party thereto, Tenant shall be liable to
            Landlord for reasonable attorneys' fees and court costs incurred by
            Landlord in connection with such appeal.

            If either party commences any litigation against the other party or
            files an appeal of a decision arising out of or in connection with
            the Lease, the prevailing party shall be entitled to recover from
            the other party reasonable attorneys' fees and costs of suit. If
            Landlord employs a collection agency to recover delinquent charges,
            Tenant agrees to pay all collection agency and attorneys' fees
            charged to Landlord in addition to Rent, late charges, interest and
            other sums payable under this Lease.

      h.    Landlord's Successors. In the event of a sale or conveyance by
            Landlord of the Building containing the Premises, the same shall
            operate to release Landlord from any further liability under this
            Lease, including as to any Security Deposit to the extent
            transferred to Landlord's successor-in-interest, and in such event
            Landlord's successor in interest shall be solely responsible for all
            further obligations of Landlord under this Lease.

      i.    Interpretation. This Lease shall be construed and interpreted in
            accordance with the laws of the state in which the Premises are
            located. This Lease constitutes the entire agreement between the
            parties with respect to the Premises, except for such guarantees or
            modifications as may be executed in writing by the parties from time
            to time. When required by the context of this Lease, the singular
            shall include the plural, and the masculine shall include the
            feminine and/or neuter. "Party" shall mean Landlord or Tenant. If
            more than one person or entity constitutes Landlord or Tenant, the
            obligations imposed upon that party shall be joint and several. The
            enforceability, invalidity or illegality of any provision shall not
            render the other provisions unenforceable, invalid or illegal,

      j.    Auctions. Tenant shall not conduct, nor permit to be conducted,
            either voluntarily or involuntarily, any auction upon the Premises
            without first having obtained Landlord's prior written consent.
            Notwithstanding

                                     -21-
<PAGE>

anything to the contrary in this Lease. Landlord shall not be obligated to
exercise any standard of reasonableness in determining whether to grant such
consent.

k.    Conflict.  Any conflict between the printed provisions of this Lease and
      the typewritten or handwritten provisions shall be controlled by the
      typewritten or handwritten provisions.

l.    Offer.  Preparation of this Lease by Landlord or Landlord's agent and
      submission of same to Tenant shall not be deemed an offer to lease to
      Tenant. This Lease is not intended to be binding until executed by all
      Parties hereto.

m.    Amendments.  This Lease may be modified only in writing, signed by the
      Parties in interest at the time of the modification. The parties shall
      amend this Lease from time to time to reflect any adjustments that are
      made to the Base Rent or other Rent payable under this Lease. As long as
      they do not materially change Tenant's obligations hereunder. Tenant
      agrees to make reasonable non-monetary modifications to this Lease as may
      be reasonably required by Lender(s) in connection with the obtaining of
      normal financing or refinancing of the property of which the Premises are
      a part.

n.    Construction.  The Landlord and Tenant acknowledge that each has had its
      counsel review this Lease. and hereby agree that the normal rule of
      construction to the effect that any ambiguities are to be resolved against
      the drafting party shall not be employed in the interpretation of this
      Lease or in any amendments or exhibits hereto.

o.    Captions.  Article, section and paragraph captions are not a part hereof.

p.    Exhibits. For reference purposes the Exhibits are listed below:

      Exhibit A: The Premises
      Exhibit B: Business Park
      Exhibit C: Rules and Regulations
      Exhibit D: Covenants, Conditions And Restrictions

LIMAR REALTY CORP. #17, a California        DOCENT, INC., a Delaware corporation
corporation


By:    /s/ Theodore H. Kruttschnitt           By:     /s/ Dave Ellett
      -----------------------------------            ---------------------------
Name:      Theodore H. Kruttschnitt           Name:   Dave Ellett
                                                     ---------------------------
Title:     President                          Title:  President & CEO
                                                     ---------------------------
Date:      10/19/99                           Date:   10/8/99
      -----------------------------------            ---------------------------


By:    /s/ Theodore H. Kruttschnitt           By:     /s/ Donald V. Fluken
      -----------------------------------            ---------------------------
Name:      Theodore H. Kruttschnitt           Name:   Donald V. Fluken
                                                     ---------------------------
Title:     Secretary                          Title:  V.P. & CFO
                                                     ---------------------------
Date:      10/19/99                           Date:   10/7/99

                                     -22-
<PAGE>

                                   EXHIBIT A

                                 The Premises
                                 ------------

This Exhibit A is attached to and made a part of that certain Lease (the
"Lease") dated September 22, 1999 by and between Limar Realty Corp. #17 as
Landlord and Docent, Inc. as Tenant.

                           [SITE PLAN APPEARS HERE]
<PAGE>

                                    EXHIBIT B

                                The Business Park
                                -----------------

This Exhibit B is attached to and made a part of that certain Lease (the
"Lease") dated September 22. 1999 by and between Limar Realty Corp. #17 as
Landlord and Docent. Inc. as Tenant.

      The land referred to in this report is situated in the State of
      California, County of SANTA CLARA and is described as follows:

All that certain Real Property in the City of Mountain View, County of Santa
Clara, State of California, described as follows:

All of Parcel 1, as shown upon that certain Map entitled, "Parcel Map". which
Map was filed for record in the Office of the Recorder of the County of Santa
Clara, State of California, on May 8, 1972 in Book 300 of Maps, at Page 43.
<PAGE>

                                   EXHIBIT C

                              Rules & Regulations
                              -------------------

This Exhibit C is attached to and made a part of that certain Lease dated
September 22, 1999 by and between Limar Realty Corp. #17 as Landlord and Docent,
Inc. as Tenant.

For the purpose of these Rules & Regulations the word Premises shall refer to
the Premises Tenant is leasing and the Property containing the Premises as
described in the Lease.

1.    No sign, placard, picture, advertisement, name or notice (collectively,
      "Signs") shall be installed or displayed on any part of the Premises
      without the prior written consent of Landlord, except that Tenant may post
      Signs inside the Building which are not visible from the exterior of the
      Building. Landlord shall have the right to remove, at Tenant's expense and
      without notice, any sign installed or displayed in violation of this rule.
      All approved signs or lettering on doors and walls shall be printed,
      painted, affixed or inscribed at the expense of Tenant.

2.    Except as consented to in writing by Landlord, no draperies, curtains,
      blinds, shades, screens or other devices shall be hung at or used in
      connection with any window or exterior door or doors of the Premises and
      no awning shall be permitted on any part of the Premises. Tenant shall not
      place anything against or near glass partitions or doors or windows which
      may appear unsightly from outside the Premises.

3.    Neither Tenant nor any employee or invitee of Tenant, shall make any
      structural roof or terrace penetrations.

4.    Tenant shall not cause any unnecessary labor by carelessness or
      indifference to the good order and cleanliness of the Premises. Landlord
      shall not in any way be responsible to any Tenant for any loss of property
      on the Premises, or for any damage to any Tenant's property.

5.    Landlord will furnish Tenant, free of charge, with up to six (6) keys to
      the Premises.

6.    If Tenant requires telegraphic, telephonic, burglar alarm or similar
      services, it shall first obtain, and comply with, Landlord's reasonable
      instructions in their installation.

7.    Tenant shall not place a load upon any floor of the Premises which exceeds
      the load per square foot which such floor was designed to carry and which
      is allowed by law. Landlord shall have the reasonable right to prescribe
      the weight, size and position of all equipment, materials, furniture or
      other property brought into the Premises. Heavy objects shall, if
      considered necessary by Landlord, stand on such platforms as determined by
      Landlord to be necessary to properly distribute the weight. Business
      machines and mechanical equipment belonging to Tenant, which cause noise
      or vibration that may be transmitted to the structure of the Premises to
      such a degree as to be objectionable to Landlord, shall be placed and
      maintained by Tenant, at Tenant's expense, on vibration eliminators or
      other devices sufficient to eliminate noise or vibrations. Landlord will
      not be responsible for loss of, or damage to, any such equipment or other
      property from any cause, and all damage done to the Premises by
      maintaining or moving such equipment or other property shall be repaired
      at the expense of Tenant.

8.    Tenant shall not use or keep in the Premises any kerosene, gasoline or
      inflammable or combustible fluid or material other than those limited
      quantities necessary for the operation or maintenance of office equipment.
      Tenant shall not use or permit to be used in the Premises any foul or
      noxious gas or substance, or permit or allow the Premises to be occupied
      or used in a manner offensive or objectionable to Landlord by reason of
      noise, odors or vibrations not bring or keep or permit to be brought or
      kept in the Premises any animal life form, other than human, except seeing
      eye dogs when in the company of their masters.

9.    Tenant shall not waste electricity, water or air-conditioning and agrees
      to cooperate fully with Landlord to comply with any governmental
      energy-saving rules, laws or regulations of which Tenant has actual
      notice.

10.   Landlord reserves the right, exercisable with one hundred twenty (120)
      days prior written notice but without liability to Tenant, to change the
      name and street address of the Premises.

11.   Tenant shall close and lock the doors of its Premises and entirely shut
      off all water faucets or other water apparatus, and other equipment which
      is not required to be continuously run.

12.   The toilet rooms, toilets, urinals, wash bowls and other apparatus shall
      not be used for any purpose other than that for which they were
      constructed and no foreign substance of any kind whatsoever shall be
      thrown therein. The expense of any breakage, stoppage or damage resulting
      for the violation of this rule shall be borne by the Tenant who, or whose
      employees or invitees, shall have caused it.
<PAGE>

                                   EXHIBIT C

                              Rules & Regulations
                              -------------------
                                  (continued)

13.   Tenant shall not sell, or permit the retail sale of newspapers, magazines,
      periodicals, theater tickets or any other goods or merchandise to the
      general public in or on the Premises. Tenant shall not make any
      room-to-room solicitation of business from other tenants in the Business
      Park. Tenant shall not use the Premises for any business or activity other
      than that specifically provided for in Tenants Lease. Notwithstanding the
      above, Tenant shall have the right to install vending machines for use by
      Tenant, its employees and invitees.

14    Tenant shall not interfere with radio or television broadcasting or
      reception from or in neighboring areas.

15.   Canvassing, soliciting and distribution of handbills or any other written
      materials, and peddling in the Business Park are prohibited, and Tenant
      shall cooperate to prevent same.

16.   Landlord reserves the right to exclude or expel from the Premises any
      person who, in Landlord's judgment, is intoxicated or under the influence
      of liquor or drugs or who is in violation of any of the Rules and
      Regulations of the Premises or in violation of the CC&R's.

17.   Tenant shall store all its trash and garbage within its Premises or in
      reasonable locations specifically identified by Landlord for such
      purposes. Tenant shall not place in any trash box or receptacle any
      material which cannot be disposed of in the ordinary and customary manner
      of trash and garbage disposal. All garbage and refuse disposal shall be
      made in accordance with reasonable directions issued from time to time by
      Landlord.

18.   The Premises shall not be used for the storage of merchandise held for
      sale to the general public, or for lodging nor shall the Premises by used
      for any improper, immoral or objectionable purpose. No cooking shall be
      done or permitted by any tenant on the Premises, except that use by Tenant
      in its kitchen, if any, located in the Premises and Underwriters
      Laboratory's approved equipment for brewing coffee, tea, hot chocolate and
      similar beverages and microwaving food shall be permitted, provided that
      such kitchen, equipment and use is in accordance with all applicable
      federal, state, county and city laws, codes, ordinances, rules and
      regulations.

19.   Tenant shall not use in any part of the Premises any hand truck except
      those equipped with rubber tires and side guards or such other reasonable
      material-handling equipment as Landlord may approve.

20.   Without the written consent of Landlord, Tenant shall not use the name of
      the Business Park in connection with or in promoting or advertising the
      business of Tenant except as Tenant's address.

21.   Tenant shall comply with all safety, fire protection and evacuation
      procedures and regulations established by Landlord or any governmental
      agency.

22.   Tenant assumes any and all responsibility for protecting its Premises from
      theft, robbery and pilferage, Which includes locking doors and securing
      other means of entry to the Premises closed.

23.   The requirements of Tenant will be attended to only upon appropriate
      application to the office of Landlord by an authorized individual.
      Employees of Landlord shall not perform any work or do anything outside of
      their regular duties unless under special instructions from Landlord.

24.   Tenant shall not park its vehicles in any parking areas outside the
      Business Park. Tenant shall not store or abandon vehicles in the Business
      Park parking areas nor park any vehicles in the Business Park parking
      areas other than automobiles, motorcycles, motor driven or non-motor
      driven bicycles, four-wheeled trucks, or other equipment used in the
      operation of Tenant's business. Tenant, its agents, employees and invitees
      shall not park any one (1) vehicle in more than one (1) parking space.

25.   Landlord reserves the right to make such other reasonable Rules and
      Regulations as, in its judgment, may from time to time be appropriate for
      safety and security, for care and cleanliness of the Premises and for the
      preservation of good order therein. Tenant agrees to abide for all such
      Rules and Regulations hereinabove stated and any additional Rules and
      Regulations which are adopted.

26.   Tenant shall be responsible for the observance of all of the foregoing
      Rules and Regulations by Tenant's employees, agents, clients, customers,
      invitees and guests.
<PAGE>

                                   EXHIBIT D

                    Covenants, Conditions and Restrictions
                    --------------------------------------

This Exhibit D is attached to and made a part of that certain Lease (the
"Lease") dated September 22, 1999 by and between Limar Realty Corp. #17 as
Landlord and Docent. Inc. as Tenant.

                                [IMAGE OMITTED]
<PAGE>

                                   EXHIBIT D

                    Covenants, Conditions and Restrictions
                    --------------------------------------
                                  (Continued)

                                [IMAGE OMITTED]