<PAGE>

                                                                   EXHIBIT 10.10


                          IRVINE OAKS EXECUTIVE PARK
                          --------------------------

                                  OFFICE LEASE
                                  ------------

     This Office Lease (the "LEASE"), dated as of the date set forth in Section
1 of the Summary of Basic Lease Information (the "SUMMARY"), below, is made by
and between MAGELLAN IRVINE OAKS LIMITED PARTNERSHIP, an Arizona limited
partnership ("LANDLORD"), and MICROSIM CORPORATION, a California corporation
("TENANT").

                       SUMMARY OF BASIC LEASE INFORMATION
                       ----------------------------------

TERMS OF LEASE                                DESCRIPTION
--------------                    --------------------------------------------
1.   Date:                        February 5, 1997

2.   Premises
     (Article 1).

     2.1  Building:               That certain building to be constructed by
                                  Landlord in accordance with the terms of the
                                  Tenant Work Letter, which is to be located at
                                  16275 Laguna Canyon Road, Irvine, California

     2.2  Premises:               Approximately 42,756 rentable square feet of
                                  space (subject to adjustment as set forth in
                                  Section 1.2 of this Lease) comprising the
                                  entire Building, as further set forth in
                                  EXHIBIT A to the Office Lease.

     2.3  Project:                Irvine Oaks Executive Park
                                  16251 - 16277 Laguna Canyon Road
                                  Irvine, California 92618
3.  Lease Term
    (Article 2).

    3.1  Length of Term:          Seven (7) years.

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     3.2  Lease Commencement
          Date:                   The earlier to occur of (i) the date upon
                                  which Tenant first commences to conduct
                                  business in the Premises (not including
                                  Tenant's 30-day move-in and fixturization
                                  period as set forth in Section 5.1 of the
                                  Tenant Work Letter), and (ii) the date upon
                                  which the Premises are "Ready for Occupancy,"
                                  at that term is defined in the Tenant Work
                                  Letter (and which date is contingent upon
                                  Landlord receiving a certificate of occupancy
                                  or its legal equivalent allowing occupancy of
                                  the Premises), which date is anticipated to
                                  be August 1, 1997.

     3.3  Lease Expiration Date:  The date immediately preceding the 7th
                                  anniversary of the Lease Commencement Date.

4.  Base Rent (Article 3):        (Subject to adjustment as set forth in
                                  Section 1.2 of the Lease).


<TABLE>
<CAPTION>
                                                    Monthly
                             Monthly              Rental Rate
                           Installment            per Rentable
     Lease Year            of Base Rent           Square Foot
     ----------            ------------           ------------
     <S>                   <C>                    <C>
       1 - 2                $44,893.80               $ 1.05
       3 - 5                $47,031.60               $ 1.10
       6 - 7                $51,734.76               $ 1.21

</TABLE>
             (Note:  Tenant has no obligation to pay any Base Rent
           attributable to the first (1st) month of the Lease Term)

5.   Tenant's Share
     (Article 4):

     5.1  Tenant's Building
           Share:                 100%.

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     5.2  Tenant's Project
          Share:                  Approximately 14%.  (Subject to adjustment as
                                  set forth in Section 1.2 of the Lease).

6.   Permitted Use
     (Article 5):                 General office use, software design,
                                  duplication and shipment, and any other
                                  legally permitted use consistent with a
                                  first-class office park and in compliance
                                  with any covenants, conditions and
                                  restrictions recorded against the Project.

7.   Security Deposit; Letter
     of Credit
     (Article 21):                $51,734.76.

8.   Parking Ratio
     (Article 28):                Four (4) parking spaces for every 1,000
                                  rentable square feet of the Premises, of
                                  which up to one (1) parking space for every
                                  3,000 rentable square feet of the Premises
                                  shall be a reserved parking space.

9.   Address of Tenant
     (Section 29.18):             MicroSim Corporation
                                  20 Fairbanks
                                  Irvine, California  92718
                                  Attention: Ms. Wendi Hall
                                  (Prior to Lease Commencement Date)

                                  and

                                  Irvine Oaks Executive Park, Bldg. No. 3
                                  16275 Laguna Canyon Road
                                  Irvine, California
                                  Attention: Ms. Wendi Hall
                                  (After Lease Commencement Date)

                                  in either case with a copy to:

                                  McDermott, Will & Emery
                                  2049 Century Park East
                                  Los Angeles, California 90067
                                  Attention: Joel M. Bernstein, Esq.

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10.  Address of Landlord
     (Section 29.18):             Magellan-New America Asset Management, Inc.
                                  16261 Laguna Canyon Road
                                  Irvine, California 92718
                                  Attention:  Property Manager

                                  and

                                  Magellan Corporations
                                  2198 East Camelback Road
                                  Suite 325
                                  Phoenix, Arizona  85016
                                  Attention:  Ms. Ulrike Gross

                                  and

                                  (only as to notices of default and other
                                  legal notices)
                                  Allen, Matkins, Leck, Gamble & Mallory
                                  1999 Avenue of the Stars, Suite 1800
                                  Los Angeles, California 90067
                                  Attention:  Anton N. Natsis, Esq.

11.  Broker(s)
     (Section 29.24):             Matlow-Kennedy Commercial Real Estate Services
                                  4510 East Pacific Coast Highway
                                  Suite 100
                                  Long Beach, California 90804

                                  and

                                  Cushman & Wakefield of California, Inc.
                                  1920 Main Street
                                  Suite 100
                                  Irvine, California 92614

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12.  Additional Tenant Rights:    A.  One (1) Option to Expand into
                                  approximately 10,000 square feet in the
                                  Project, between the 60th and 68th months of
                                  the Lease Term, pursuant to the terms of
                                  Section 1.3 of this Lease.

                                  B.  Two (2) Options to Extend the Lease Term
                                  for a period of five (5) years each, pursuant
                                  to the terms of Section 2.2 of this Lease.

13.  Tenant Improvement Allowance
     (Exhibit B, Section 2.1):    $25.00 per usable square foot of the Premises.


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                                   ARTICLE 1
                                   ---------

                 PREMISES, BUILDING, PROJECT, AND COMMON AREAS
                 ---------------------------------------------

     1.1  PREMISES, BUILDING, PROJECT AND COMMON AREAS.
          --------------------------------------------

          1.1.1  THE PREMISES.  Landlord hereby leases to Tenant and Tenant
hereby leases from Landlord the premises set forth in Section 2.2 of the Summary
(the "PREMISES").  The outline of the Premises is set forth in EXHIBIT A
attached hereto and each floor or floors of the Premises has the number of
rentable square feet as set forth in Section 2.2 of the Summary.  The parties
hereto agree that the lease of the Premises is upon and subject to the terms,
covenants and conditions herein set forth, and Tenant covenants as a material
part of the consideration for this Lease to keep and perform each and all of
such terms, covenants and conditions by it to be kept and performed and that
this Lease is made upon the condition of such performance.  The parties hereto
hereby acknowledge that the purpose of EXHIBIT A is to show the approximate
location of the Premises in the "Building," as that term is defined in Section
1.1.2, below, only, and such Exhibit is not meant to constitute an agreement,
representation or warranty as to the construction of the Premises, the precise
area thereof or the specific location of the "Common Areas," as that term is
defined in Section 1.1.3, below, or the elements thereof or of the accessways to
the Premises or the "Project," as that term is defined in Section 1.1.2, below.
Except as specifically set forth in this Lease and in the Tenant Work Letter
attached hereto as EXHIBIT B (the "TENANT WORK LETTER"), Landlord shall not be
obligated to provide or pay for any improvement work or services related to the
improvement of the Premises.  Tenant also acknowledges that neither Landlord nor
any agent of Landlord has made any representation or warranty regarding the
condition of the Premises, the Building or the Project or with respect to the
suitability of any of the foregoing for the conduct of Tenant's business, except
as specifically set forth in this Lease and the Tenant Work Letter.  The taking
of possession of the Premises by Tenant shall conclusively establish that the
Premises and the Building were at such time in good and sanitary order,
condition and repair, subject to Landlord's obligation to repair, reasonably
promptly, (a) any outstanding "punch-list" items, and (b) any latent defects in
the Building.

          1.1.2  THE BUILDING AND THE PROJECT.  The Premises are a part of the
building set forth in Section 2.1 of the Summary (the "BUILDING").  The Building
shall be constructed by Landlord in accordance with the terms of the Tenant Work
Letter, and shall be part of an office project known as "IRVINE OAKS EXECUTIVE
PARK."  The term "PROJECT," as used in this Lease, shall mean (i) the Building
and the Common Areas, (ii) the land (which is improved with landscaping, parking
areas and other improvements) upon which the Building and the Common Areas are
located, (iii) the other office buildings located within the Project and the
land upon which such adjacent office buildings are located, and (iv) at
Landlord's discretion, any additional real property, areas, land, buildings or
other improvements added thereto outside of the Project.

          1.1.3  COMMON AREAS.  Tenant shall have the non-exclusive right to use
in common with other tenants in the Project, and subject to the rules and
regulations referred to in Article 5 of this Lease, those portions of the
Project which are provided, from time to time, for use in common by Landlord,
Tenant and any other tenants of the Project (such areas, together

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with such other portions of the Project designated by Landlord, in its
discretion, including certain areas designated for the exclusive use of certain
tenants, or to be shared by Landlord and certain tenants, are collectively
referred to herein as the "COMMON AREAS"). The manner in which the Common Areas
are maintained and operated shall be at the sole discretion of Landlord and the
use thereof shall be subject to such rules, regulations and restrictions as
Landlord may make from time to time. Landlord reserves the right to close
temporarily, make alterations or additions to, or change the location of
elements of the Project and the Common Areas.

     1.2  VERIFICATION OF RENTABLE SQUARE FEET OF PREMISES, BUILDING, AND
PROJECT.  For purposes of this Lease, "RENTABLE SQUARE FEET" shall be calculated
based on the "drip line" area of the Building, as measured to the exterior walls
on each floor of the Building, without exclusions for any soffits or
penetrations.  The "USABLE SQUARE FEET" of the Premises shall be determined
pursuant the Standard Method For Measuring Office Buildings, ANSI Z65.1989
("BOMA").  The rentable square footage of the Project shall include all of the
Building Common Areas.  Prior to the "Lease Commencement Date," as that terms is
defined in Article 3, below, a space planner or architect, mutually agreed upon
by Landlord and Tenant, shall determine  the rentable square footage of Premises
in accordance with the terms of this Section 1.2.  The parties agree that the
determination of the rentable square footage of the Premises made by such space
planner or architect shall be binding upon the parties, and shall not be subject
to further verification during the Lease Term.  In the event that the rentable
area of the Project shall change due to subsequent alterations and/or other
modifications to the Project, the rentable area of the Project shall be
appropriately adjusted as of the date of such alteration and/or other
modification, based upon the written verification by Landlord's space planner of
such revised rentable area.  In the event of any such adjustment to the rentable
area of the Project, all amounts, percentages and figures appearing or referred
to in this Lease based upon such rentable area (including, without limitation,
the amount of the "Tenant's Project Share," as that term is defined in Section
4.2.10, below) shall be modified in accordance with such determination.

     1.3  EXPANSION SPACE.  Landlord hereby grants to the originally named
Tenant herein ("Original Tenant") the right to lease up to 10,000 rentable
square feet of space in the Project (the "EXPANSION SPACE"), the location or
locations of which Expansion Space shall be designated by Landlord, upon the
terms and conditions set forth in this Section 1.3 and this Lease.

          1.3.1  METHOD OF EXERCISE.  The expansion option contained in this
Section 1.3 shall be exercised only by Original Tenant and only in the following
manner:  (i) Tenant shall deliver notice to Landlord not more than ten (10)
months nor less than four (4) months prior to the first day of the 5th Lease
Year, (a) stating that Tenant is interested in exercising its option and (b)
setting forth the required total size (not to exceed 10,000 rentable square
feet) of the desired Expansion Space; (ii) Landlord, after receipt of Tenant's
notice, shall deliver notice (the "EXPANSION RENT NOTICE") to Tenant not less
than three (3) months prior to the first day of the 5th Lease Year, setting
forth the "Expansion Rent," as that term is defined in Section 1.3 of this Lease
and describing the Expansion Space, including its location and the improvements
contained therein, with reasonable particularity; and (iii) if Tenant wishes to
exercise its expansion option, Tenant shall, on or before the later of (A) the
date occurring two (2) months prior to the first day of the 5th Lease Year, and
(B) the date occurring thirty (30) days after

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Tenant's receipt of the Expansion Rent Notice, exercise the option by delivering
written notice thereof to Landlord.

          1.3.2  DELIVERY OF THE EXPANSION SPACE.  Landlord shall deliver the
Expansion Space (which shall be equal to the amount of space desired by Tenant
plus or minus up to 1,000 rentable square feet) to Tenant at any time prior to
the end of the eighth (8th) month of the 5th Lease Year, at Landlord's option
(the "Delivery Period").  The delivery of the Expansion Space may, at Landlord's
option, be in increments, and the Expansion Space may consist of one or more
(but no more than three (3)) separate spaces in one or more buildings of the
Project.

          1.3.3  EXPANSION RENT.  The Rent payable by Tenant for Expansion Space
leased by Tenant (the "EXPANSION RENT") shall be equal to the rent including all
escalations, at which, as of the commencement of Tenant's proposed lease of the
Expansion Space, tenants are leasing non-sublease, non-encumbered, non-equity
space comparable in size, location and quality to the Premises, for a term equal
to the then remaining Lease Term, which comparable space is located in the
Project, taking into consideration the following concessions:  (a) rental
abatement concessions, if any, being granted such tenants in connection with
such comparable space; (b) tenant improvements or allowances provided or to be
provided for such comparable space, taking into account, and deducting the value
of, the existing improvements in the such space, such value to be based upon the
age, quality and layout of the improvements and the extent to which the same can
be utilized by a general office user, and further provided that any such
allowances shall be prorated to reflect the actual term of Tenant's lease of the
Expansion Space.

          1.3.4  CONSTRUCTION OF EXPANSION SPACE.  Tenant shall take the
Expansion Space in its "as is" condition, and the construction of improvements
in the Expansion Space shall comply with the terms of Article 8 of this Lease.

          1.3.5  AMENDMENT TO LEASE.  If Tenant timely exercises Tenant's right
to lease Expansion Space as set forth herein, Landlord and Tenant shall within
fifteen (15) days thereafter execute an amendment adding such Expansion Space to
the Lease upon the same terms and conditions as the initial Premises, except as
otherwise set forth in this Section 1.3, and provided that the terms of the
Tenant Work Letter shall not apply with respect to the Expansion Space.  Tenant
shall commence payment of Rent for the Expansion Space and the term of the
Expansion Space shall commence upon the date of delivery of the Expansion Space
to Tenant (the "Expansion Space Commencement Date").  The lease term of the
Expansion Space shall expire on the Lease Expiration Date.

          1.3.6  NO DEFAULTS.  The rights contained in this Section 1.3 shall be
personal to Original Tenant, may only be exercised by Original Tenant (and not
any assignee, sublessee or other transferee of Tenant's interest in this Lease)
if Original Tenant continues to directly lease (i.e., has not sublet) the entire
Premises.  Tenant shall not have the right to lease Expansion Space as provided
in this Section 1.3, if, as of the date of the attempted exercise of the
expansion option by Tenant, or as of the scheduled date of delivery of such
Expansion Space to Tenant, Tenant is in default under this Lease or Tenant has
previously been in default under this Lease more than once.

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                                   ARTICLE 2
                                   ---------

                LEASE TERM; OPTION TERMS; OUTSIDE DELIVERY DATE
                -----------------------------------------------

     2.1  INITIAL TERM.  The terms and provisions of this Lease shall be
effective as of the date of this Lease.  The term of this Lease (the "LEASE
TERM") shall be as set forth in Section 3.1 of the Summary, shall commence on
the date set forth in Section 3.2 of the Summary (the "LEASE COMMENCEMENT
DATE"), and shall terminate on the date set forth in Section 3.3 of the Summary
(the "LEASE EXPIRATION DATE") unless this Lease is sooner terminated as
hereinafter provided.  For purposes of this Lease, the term "LEASE YEAR" shall
mean each consecutive twelve (12) month period during the Lease Term.  At any
time during the Lease Term, Landlord may deliver to Tenant a notice in the form
as set forth in EXHIBIT C, attached hereto, as a confirmation only of the
information set forth therein, which Tenant shall execute and return to Landlord
within five (5) days of receipt thereof.

     2.2  OPTION TERM.

          2.2.1  OPTION RIGHT.  Landlord hereby grants the Original Tenant two
(2) options to extend the Lease Term for a period of five (5) years each (each,
an "OPTION TERM"), which options shall be exercisable only by written notice
delivered by Tenant to Landlord as provided below, provided that, as of the date
of delivery of such notice, Tenant is not in default under this Lease and Tenant
has not previously been properly declared in default under this Lease more than
once.  Upon the proper exercise of any such option to extend, and provided that,
as of the end of the initial Lease Term or initial Option Term, as the case may
be, Tenant is not in default under this Lease and Tenant has not previously been
properly declared in default under this Lease more than once, the Lease Term, as
it applies to the Premises, shall be extended for a period of five (5) years.
The rights contained in this Section 2.2 shall be personal to the Original
Tenant and may only be exercised by the Original Tenant (and not any assignee,
sublessee or other transferee of Tenant's interest in this Lease) if the
Original Tenant occupies the entire Premises.

          2.2.2  OPTION RENT.  The rent payable by Tenant during the Option Term
(the "OPTION RENT") shall be equal to the greater of (i) the Rent being paid by
Tenant as of the expiration of the initial Lease Term or initial Option Term, as
the case may be, and (ii) the rent including all escalations, at which, as of
the commencement of the Option Term, tenants are leasing non-sublease, non-
encumbered, non-equity space comparable in size, location and quality to the
Premises, for a term of five (5) years, which comparable space is located in the
Project, taking into consideration the following concessions:  (a) rental
abatement concessions, if any, being granted such tenants in connection with
such comparable space; and (b) tenant improvements or allowances provided or to
be provided for such comparable space, taking into account, and deducting the
value of, the existing improvements in the Premises, such value to be based upon
the age, quality and layout of the improvements and the extent to which the same
can be utilized by Tenant based upon the fact that the precise tenant
improvements existing in the Premises are specifically suitable to Tenant.

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          2.2.3  EXERCISE OF OPTION.  The options contained in this Section 2.2
shall be exercised by Tenant, if at all, only in the following manner:  (i)
Tenant shall deliver written notice to Landlord not more than fourteen (14)
months nor less than thirteen (13) months prior to the expiration of the initial
Lease Term or initial Option Term, as applicable, stating that Tenant is
interested in exercising its option; (ii) Landlord, after receipt of Tenant's
notice, shall deliver notice (the "OPTION RENT NOTICE") to Tenant not less than
eleven (11) months prior to the expiration of the initial Lease Term or initial
Option Term, as applicable, setting forth the Option Rent; and (iii) if Tenant
wishes to exercise such option, Tenant shall, on or before the earlier of (A)
the date occurring ten (10) months prior to the expiration of the initial Lease
Term or initial Option Term, as applicable, and (B) the date occurring thirty
(30) days after Tenant's receipt of the Option Rent Notice, exercise the option
by delivering written notice thereof to Landlord.

     2.3  OCCURRENCE OF LEASE COMMENCEMENT DATE.  Landlord shall cause the Lease
Commencement Date to occur on or before December 31, 1997 (the "OUTSIDE DATE").

          2.3.1  OUTSIDE DATE OF LEASE COMMENCEMENT DATE.  If Landlord does not
cause the Lease Commencement Date to occur by the Outside Date, then the sole
remedy of Tenant for such failure shall be the right to deliver a notice to
Landlord (a "TERMINATION NOTICE") electing to terminate this Lease effective
upon the date occurring five (5) business days following receipt by Landlord of
the Termination Notice (the "EFFECTIVE DATE").  The Termination Notice must be
delivered by Tenant to Landlord, if at all, not earlier than the Outside Date
nor later than five (5) business days after the Outside Date.  The effectiveness
of any such Termination Notice delivered by Tenant to Landlord shall be governed
by the terms of this Section 2.3.

          2.3.2  OTHER TERMS.  The Effective Date and the Outside Date shall be
extended to the extent of any delays beyond the reasonable control of Landlord,
including "Force Majeure Delays", as that term is defined in Section 29.16 of
this Lease, and any delay or delays encountered by Landlord affecting the work
of construction of the Tenant's improvements in the Premises because of delays
due to excess waiting periods for obtaining governmental permits or approval
beyond the time periods normally required to obtain such permits or approvals.
Upon any termination as set forth in this Section 2.3, Landlord and Tenant shall
be relieved from any and all liability to each other resulting hereunder.

                                   ARTICLE 3
                                   ---------

                                   BASE RENT
                                   ---------

     Tenant shall pay, without prior notice or demand, to Landlord or Landlord's
agent at the management office of the Project, or, at Landlord's option, at such
other place as Landlord may from time to time designate in writing, by a check
for currency which, at the time of payment, is legal tender for private or
public debts in the United States of America, base rent ("BASE RENT") as set
forth in Section 4 of the Summary, payable in equal monthly installments as set
forth in Section 4 of the Summary  in advance on or before the first day of each
and every calendar month during the Lease Term, without any setoff or deduction
whatsoever.  Landlord agrees that

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it shall invoice Tenant monthly for such amounts. Notwithstanding the foregoing,
Tenant shall have no obligation to pay any Base Rent which is attributable to
the first (1st) month of the Lease Term. The Base Rent for the first full month
of the Lease Term which occurs after the expiration of any free rent period
shall be paid at the time of Tenant's execution of this Lease. If any Rent
payment date (including the Lease Commencement Date) falls on a day of the month
other than the first day of such month or if any payment of Rent is for a period
which is shorter than one month, the Rent for any fractional month shall accrue
on a daily basis for the period from the date such payment is due to the end of
such calendar month or to the end of the Lease Term at a rate per day which is
equal to 1/365 of the applicable annual Rent. All other payments or adjustments
required to be made under the terms of this Lease that require proration on a
time basis shall be prorated on the same basis.

                                   ARTICLE 4
                                   ---------

                                ADDITIONAL RENT
                                ---------------

     4.1  GENERAL TERMS.  In addition to paying the Base Rent specified in
Article 3 of this Lease, Tenant shall pay "Tenant's Building Share" of the
annual "Building Direct Expenses," as those terms are defined in Sections 4.2.9
and 4.2.2 of this Lease, respectively, and "Tenant's Project Share" of the
annual "Project Direct Expenses", as those terms are defined in Sections 4.2.10
and 4.2.1 of this Lease, respectively.  Such payments by Tenant, together with
any and all other amounts payable by Tenant to Landlord pursuant to the terms of
this Lease, are hereinafter collectively referred to as the "ADDITIONAL RENT",
and the Base Rent and the Additional Rent are herein collectively referred to as
"RENT."  All amounts due under this Article 4 as Additional Rent shall be
payable for the same periods and in the same manner as the Base Rent.  Without
limitation on other obligations of Tenant which survive the expiration of the
Lease Term, the obligations of Tenant to pay the Additional Rent provided for in
this Article 4 shall survive the expiration of the Lease Term.

     4.2  DEFINITIONS OF KEY TERMS RELATING TO ADDITIONAL RENT.  As used in this
Article 4, the following terms shall have the meanings hereinafter set forth:

          4.2.1  "PROJECT DIRECT EXPENSES" shall mean the portion of "Operating
Expenses," as that term is defined in Section 4.2.7 below, which is not
attributable to any particular Building in the Project, but which instead
relates to the Project as a whole.

          4.2.2  "BUILDING DIRECT EXPENSES" shall mean "Building Operating
Expenses" and "Building Tax Expenses", as those terms are defined in Sections
4.2.3 and 4.2.4, below, respectively.

          4.2.3  "BUILDING OPERATING EXPENSES" shall mean the portion of
"Operating Expenses," as that term is defined in Section 4.2.7 below,  allocated
to the tenants of the Building pursuant to the terms of Section 4.3.1 below.

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          4.2.4  "BUILDING TAX EXPENSES" shall mean that portion of "Tax
Expenses", as that term is defined in Section 4.2.8 below, allocated to the
tenants of the Building pursuant to the terms of Section 4.3.1 below.

          4.2.5  "DIRECT EXPENSES" shall mean "Operating Expenses" and "Tax
Expenses."

          4.2.6  "EXPENSE YEAR" shall mean each calendar year in which any
portion of the Lease Term falls, through and including the calendar year in
which the Lease Term expires, provided that Landlord, upon notice to Tenant, may
change the Expense Year from time to time to any other twelve (12) consecutive
month period, and, in the event of any such change, Tenant's Share of Building
Direct Expenses shall be equitably adjusted for any Expense Year involved in any
such change.

          4.2.7  "OPERATING EXPENSES" shall mean all expenses, costs and amounts
of every kind and nature which Landlord pays or accrues during any Expense Year
because of or in connection with the management, maintenance, security, repair,
replacement or operation of the Project, or any portion thereof.  Without
limiting the generality of the foregoing, Operating Expenses shall specifically
include any and all of the following:  (i) the cost of supplying all utilities,
the cost of operating, repairing, maintaining, and renovating the utility,
telephone, mechanical, sanitary, storm drainage, and elevator systems, and the
cost of maintenance and service contracts in connection therewith; (ii) the cost
of licenses, certificates, permits and inspections and the cost of contesting
any governmental enactments which may affect Operating Expenses, and the costs
incurred in connection with a transportation system management program or
similar program; (iii) the cost of all insurance carried by Landlord in
connection with the Project as reasonably determined by Landlord; (iv) the cost
of landscaping, relamping, and all supplies, tools, equipment and materials used
in the operation, repair and maintenance of the Project, or any portion thereof;
(v) the cost of parking area repair, restoration, and maintenance ; (vi) fees
and other costs, including management fees, consulting fees, legal fees and
accounting fees, of all contractors and consultants in connection with the
management, operation, maintenance and repair of the Project; (vii) payments
under any equipment rental agreements and the fair rental value of any
management office space (provided that such space is not in excess of 1,000
rentable square feet); (viii) the allocable portion of wages, salaries and other
compensation and benefits, including taxes levied thereon, of all persons
engaged in the operation, maintenance and security of the Project; (ix) costs
under any instrument pertaining to the sharing of costs by the Project; (x)
operation, repair, maintenance and replacement of all systems and equipment and
components thereof of the Building (provided that any such costs which are
capital in nature shall be included under item (xiii), below); (xi) the cost of
janitorial, alarm, security and other services, replacement of wall and floor
coverings, ceiling tiles and fixtures in common areas, maintenance and
replacement of curbs and walkways, repair to roofs and re-roofing; (xii)
amortization (including interest on the unamortized cost), on a straight-line
basis, of the cost of acquiring or the rental expense of personal property used
in the maintenance, operation and repair of the Project, or any portion thereof;
(xiii) the cost of capital improvements or other costs incurred in connection
with the Project (A) which are intended to effect economies in the operation or
maintenance of the Project, or any portion thereof, (B) that are required to
comply with present or anticipated conservation programs, (C) which are
replacements or modifications

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of nonstructural items located in the Common Areas required to keep the Common
Areas in good order or condition, (D) that are required under any governmental
law or regulation or (E) which are reasonably determined by Landlord to be in
the best interests of the Building and/or the Project; provided, however, that
any capital expenditure shall be amortized on a straight-line basis over its
reasonable useful life; and (xiv) costs, fees, charges or assessments imposed
by, or resulting from any mandate imposed on Landlord by, any federal, state or
local government for fire and police protection, trash removal, community
services, or other services which do not constitute "Tax Expenses" as that term
is defined in Section 4.2.8, below (provided that any assessments relating to
capital improvements to the Project or Building shall be included only to the
extent such costs would be includable under item (xiii), above). Notwithstanding
the foregoing, Operating Expenses shall not include any amounts for services
for which Tenant or other tenants of the Project contract directly with Landlord
or another service provider, and for which services Tenant or such other tenants
or occupants pay Landlord or such service provider directly.

     If the Project is not at least ninety-five percent (95%) occupied during
all or a portion of or any Expense Year, Landlord may elect to make an
appropriate adjustment to the components of Operating Expenses for such year to
determine the amount of Operating Expenses that would have been paid had the
Project been ninety-five percent (95%) occupied; and the amount so determined
shall be deemed to have been the amount of Operating Expenses for such year.
Landlord agrees that no such adjustment shall result in Landlord being
reimbursed for Operating Expenses by all tenants of the Project in an amount
which is in excess of the Operating Expenses actually paid by Landlord in
connection with the operation of the Project.

          4.2.8  TAXES.

               4.2.8.1  "TAX EXPENSES" shall mean all federal, state, county, or
local governmental or municipal taxes, fees, charges or other impositions of
every kind and nature, whether general, special, ordinary or extraordinary,
(including, without limitation, real estate taxes, general and special
assessments, transit taxes, leasehold taxes or taxes based upon the receipt of
rent, including gross receipts or sales taxes applicable to the receipt of rent,
unless required to be paid by Tenant, personal property taxes imposed upon the
fixtures, machinery, equipment, apparatus, systems and equipment, appurtenances,
furniture and other personal property used in connection with the Project, or
any portion thereof), which shall be paid or accrued during any Expense Year
(without regard to any different fiscal year used by such governmental or
municipal authority) because of or in connection with the ownership, leasing and
operation of the Project, or any portion thereof.

               4.2.8.2  Tax Expenses shall include, without limitation: (i) Any
tax on the rent, right to rent or other income from the Project, or any portion
thereof, or as against the business of leasing the Project, or any portion
thereof; (ii) Any assessment, tax, fee, levy or charge in addition to, or in
substitution, partially or totally, of any assessment, tax, fee, levy or charge
previously included within the definition of real property tax, it being
acknowledged by Tenant and Landlord that Proposition 13 was adopted by the
voters of the State of California in the June 1978 election ("PROPOSITION 13")
and that assessments, taxes, fees, levies and charges

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may be imposed by governmental agencies for such services as fire protection,
street, sidewalk and road maintenance, refuse removal and for other governmental
services formerly provided without charge to property owners or occupants, and,
in further recognition of the decrease in the level and quality of governmental
services and amenities as a result of Proposition 13, Tax Expenses shall also
include any governmental or private assessments or the Project's contribution
towards a governmental or private cost-sharing agreement for the purpose of
augmenting or improving the quality of services and amenities normally provided
by governmental agencies; (iii) Any assessment, tax, fee, levy, or charge
allocable to or measured by the area of the Premises or the Rent payable
hereunder, including, without limitation, any business or gross income tax or
excise tax with respect to the receipt of such rent, or upon or with respect to
the possession, leasing, operating, management, maintenance, alteration, repair,
use or occupancy by Tenant of the Premises, or any portion thereof; and (iv) Any
assessment, tax, fee, levy or charge, upon this transaction or any document to
which Tenant is a party, creating or transferring an interest or an estate in
the Premises.

               4.2.8.3  Any costs and expenses (including, without limitation,
reasonable attorneys' fees) incurred in attempting to protest, reduce or
minimize Tax Expenses shall be included in Tax Expenses in the Expense Year such
expenses are paid.  Tax refunds shall be credited against Tax Expenses and
refunded to Tenant regardless of when received, based on the Expense Year to
which the refund is applicable, provided that in no event shall the amount to be
refunded to Tenant for any such Expense Year exceed the total amount paid by
Tenant as Additional Rent under this Article 4 for such Expense Year.  If Tax
Expenses for any period during the Lease Term or any extension thereof are
increased after payment thereof for any reason, including, without limitation,
error or reassessment by applicable governmental or municipal authorities,
Tenant shall pay Landlord upon demand Tenant's Share of any such increased Tax
Expenses included by Landlord as Building Tax Expenses pursuant to the terms of
this Lease.  Notwithstanding anything to the contrary contained in this Section
4.2.8 (except as set forth in Section 4.2.8.1, above), there shall be excluded
from Tax Expenses (i) all excess profits taxes, franchise taxes, gift taxes,
capital stock taxes, inheritance and succession taxes, estate taxes, federal and
state income taxes, and other taxes to the extent applicable to Landlord's
general or net income (as opposed to rents, receipts or income attributable to
operations at the Project), (ii) any items included as Operating Expenses, and
(iii) any items paid by Tenant under Section 4.5 of this Lease.

          4.2.9  "TENANT'S BUILDING SHARE" shall mean the percentage set forth
in Section 6.1 of the Summary.

          4.2.10  "TENANT'S PROJECT SHARE"  "Tenant's Project Share" shall mean
the percentage set forth in Section 6.2 of the Summary.

     4.3  ALLOCATION OF DIRECT EXPENSES.

          4.3.1  METHOD OF ALLOCATION.  The parties acknowledge that the
Building is a part of a multi-building project and that the Project Direct
Expenses should be shared between the tenants of the Building and the tenants of
the other buildings in the Project.  Accordingly, as

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set forth in Section 4.2 above, Direct Expenses (which consists of Operating
Expenses and Tax Expenses) are determined annually for the Project as a whole,
and a portion of the Direct Expenses, which portion shall be determined by
Landlord on an equitable basis, shall be allocated to the tenants of the
Building (as opposed to the tenants of any other buildings in the Project) and
such portion shall be the Building Direct Expenses for purposes of this Lease.
Building Direct Expenses shall include all Direct Expenses attributable solely
to the Building.

          4.3.2  COST POOLS.  Landlord shall have the right, from time to time,
to equitably allocate some or all of the Project Direct Expenses among different
portions or occupants of the Project (the "COST POOLS"), on a commercially
reasonable basis.  Such Cost Pools may include, but shall not be limited to, the
office space tenants of a building of the Project or of the Project, and the
retail space tenants of a building of the Project or of the Project.  The Direct
Expenses within each such Cost Pool shall be allocated and charged to the
tenants within such Cost Pool in an equitable manner.

     4.4  CALCULATION AND PAYMENT OF ADDITIONAL RENT.  For each Expense Year
ending or commencing within the Lease Term, Tenant shall pay to Landlord, in the
manner set forth in Section 4.4.1, below, and as Additional Rent, an amount
equal to the sum of (i) Tenant's Building Share of Building Direct Expenses for
such Expense Year and (ii) Tenant's Project Share of Project Direct Expenses for
such Expense Year (collectively, the "EXPENSE PAYMENT").

          4.4.1  STATEMENT OF ACTUAL DIRECT EXPENSES AND PAYMENT BY TENANT.
Landlord shall endeavor to give to Tenant following the end of each Expense
Year, a statement (the "STATEMENT") which shall state the Building Direct
Expenses and Project Direct Expenses incurred or accrued for such preceding
Expense Year, and which shall indicate the amount of the Expense Payment.  Upon
receipt of the Statement for each Expense Year commencing or ending during the
Lease Term, Tenant shall pay, with its next installment of Base Rent due, the
full amount of the Expense Payment for such Expense Year (prorated to reflect
the period of the Lease Term included in such Expense Year), less the amounts,
if any, paid during such Expense Year as an "Estimated Payment," as that term is
defined in Section 4.4.2, below.  The failure of Landlord to timely furnish the
Statement for any Expense Year shall not prejudice Landlord or Tenant from
enforcing its rights under this Article 4.  Even though the Lease Term has
expired and Tenant has vacated the Premises, when the final determination is
made of Tenant's Building Share of Building Direct Expenses and Tenant's Project
Share of Project Direct Expenses for the Expense Year in which this Lease
terminates, Tenant shall immediately pay to Landlord such amount.  The
provisions of this Section 4.4.1 shall survive the expiration or earlier
termination of the Lease Term.

          4.4.2  STATEMENT OF ESTIMATED DIRECT EXPENSES.  In addition, Landlord
shall endeavor to give Tenant a yearly expense estimate statement (the "ESTIMATE
STATEMENT") which shall set forth Landlord's reasonable estimate (the
"ESTIMATE") of what the total amount of Building Direct Expenses and Project
Direct Expenses for the then-current Expense Year shall be and the estimated
payment (the "ESTIMATED PAYMENT") which shall be based upon the Estimate.  The
failure of Landlord to timely furnish the Estimate Statement for any Expense
Year shall not preclude Landlord from enforcing its rights to collect any
Estimated Payment under this

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Article 4, nor shall Landlord be prohibited from revising any Estimate Statement
or Estimated Payment theretofore delivered to the extent necessary. Thereafter,
Tenant shall pay, with its next installment of Base Rent due, a fraction of the
Estimated Payment for the then-current Expense Year (reduced by any amounts paid
pursuant to the next to last sentence of this Section 4.4.2). Such fraction
shall have as its numerator the number of months which have elapsed in such
current Expense Year, including the month of such payment, and twelve (12) as
its denominator. Until a new Estimate Statement is furnished (which Landlord
shall have the right to deliver to Tenant at any time), Tenant shall pay
monthly, with the monthly Base Rent installments, an amount equal to one-twelfth
(1/12) of the total Estimated Payment set forth in the previous Estimate
Statement delivered by Landlord to Tenant. Landlord shall maintain books and
records with respect to Building Direct Expenses and Project Direct Expenses in
accordance with generally accepted accounting and management practices,
consistently applied.

     4.5  TAXES AND OTHER CHARGES FOR WHICH TENANT IS DIRECTLY RESPONSIBLE.

          4.5.1  PERSONAL PROPERTY TAXES.  Tenant shall be liable for and shall
pay at least ten (10) days before delinquency, taxes levied against Tenant's
equipment, furniture, fixtures and any other personal property located in or
about the Premises.  If any such taxes on Tenant's equipment, furniture,
fixtures and any other personal property are levied against Landlord or
Landlord's property or if the assessed value of Landlord's property is increased
by the inclusion therein of a value placed upon such equipment, furniture,
fixtures or any other personal property and if Landlord pays the taxes based
upon such increased assessment, which Landlord shall have the right to do
regardless of the validity thereof but only under proper protest if requested by
Tenant, Tenant shall upon demand repay to Landlord the taxes so levied against
Landlord or the proportion of such taxes resulting from such increase in the
assessment, as the case may be.

          4.5.2  "ABOVE-STANDARD" IMPROVEMENTS.  If the tenant improvements in
the Premises, whether installed and/or paid for by Landlord or Tenant and
whether or not affixed to the real property so as to become a part thereof, are
assessed for real property tax purposes at a valuation higher than the valuation
at which tenant improvements conforming to Landlord's "building standard" in
other space in the Building are assessed, then the Tax Expenses levied against
Landlord or the property by reason of such excess assessed valuation shall be
deemed to be taxes levied against personal property of Tenant and shall be
governed by the provisions of Section 4.5.1, above.

          4.5.3  OTHER TAXES.  Notwithstanding any contrary provision herein,
Tenant shall pay prior to delinquency any (i) rent tax or sales tax, service
tax, transfer tax or value added tax, or any other applicable tax on the rent or
services herein or otherwise respecting this Lease, (ii) taxes assessed upon or
with respect to the possession, leasing, operation, management, maintenance,
alteration, repair, use or occupancy by Tenant of the Premises or any portion of
the Project, including the Project parking facility; or (iii) taxes assessed
upon this transaction or any document to which Tenant is a party creating or
transferring an interest or an estate in the Premises.

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          4.5.4  SERVICE CHARGES.  To the extent that, at Tenant's request,
Landlord provides any services directly to Tenant, including, without
limitation, janitorial, locksmithing, lamp replacement, or repair and
maintenance services, Tenant shall pay to Landlord, as Additional Rent and
concurrently with Tenant's payment of Base Rent to Landlord, the sum of all
costs of Landlord of such services (which cost may include an administration
fee).

                                   ARTICLE 5
                                   ---------

                                USE OF PREMISES
                                ---------------

     5.1  PERMITTED USE.  Tenant shall use the Premises solely for the Permitted
Use set forth in Section 6 of the Summary (provided that Tenant agrees that,
except for the designated warehouse space shown on the "Final Space Plan," as
defined in the Tenant Work Letter, and except for normal storage uses compatible
with the Permitted Use, the Premises shall not be used as warehouse or storage
space) and Tenant shall not use or permit the Premises or the Project to be used
for any other purpose or purposes whatsoever without the prior written consent
of Landlord, which may be withheld in Landlord's sole discretion.

     5.2  PROHIBITED USES.  Tenant further covenants and agrees that Tenant
shall not use, or suffer or permit any person or persons to use, the Premises or
any part thereof for any use or purpose contrary to the provisions of the Rules
and Regulations set forth in EXHIBIT D, attached hereto, or in violation of the
laws of the United States of America, the State of California, or the
ordinances, regulations or requirements of the local municipal or county
governing body or other lawful authorities having jurisdiction over the Project)
including, without limitation, any such laws, ordinances, regulations or
requirements relating to hazardous materials or substances, as those terms are
defined by applicable laws now or hereafter in effect.  Tenant shall not do or
permit anything to be done in or about the Premises which will in any way damage
the reputation of the Project or obstruct or interfere with the rights of other
tenants or occupants of the Project, or injure or annoy them or use or allow the
Premises to be used for any improper, unlawful or objectionable purpose, nor
shall Tenant cause, maintain or permit any nuisance in, on or about the
Premises.  Tenant shall comply with all recorded covenants, conditions, and
restrictions now or hereafter affecting the Project with respect to Tenant's use
of the Premises.

                                   ARTICLE 6
                                   ---------

                             SERVICES AND UTILITIES
                             ----------------------

     6.1  STANDARD TENANT SERVICES.  Landlord shall provide the following
services on all days (unless otherwise stated below) during the Lease Term.

          6.1.1  Landlord shall provide adequate electrical wiring and
facilities for connection to Tenant's lighting fixtures and incidental use
equipment, provided that the combined connected electrical load of the
incidental use equipment and lighting fixtures does not exceed eight (8) watts
per usable square foot of the Premises, and the electricity so furnished will be
at a nominal one hundred twenty (120) volts and no electrical circuit for the
supply of such

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incidental use equipment will require a current capacity exceeding twenty (20)
amperes, which electrical usage shall be subject to applicable laws and
regulations, including Title 24. Tenant shall bear the cost of replacement of
lamps, starters and ballasts for lighting fixtures within the Premises.

          6.1.2  Landlord shall provide city water from the regular Building
outlets for drinking, lavatory and toilet purposes in the Building Common Areas.

          6.1.3  Landlord shall provide exterior window washing services in a
manner consistent with other comparable buildings in the vicinity of the
Building.

          6.1.4  Landlord shall not provide janitorial services for the
Premises.  Tenant shall be solely responsible maintaining the Premises in a
manner consistent with a first-class office building, including, without
limitation, the following.

               6.1.4.1  Tenant shall cause the carpets or other floor coverings
in the Premises to be professionally cleaned at least once every six (6) months
during the Lease Term.

               6.1.4.2  Tenant shall cause to be provided (i) semi-annual
interior window washing, and (ii) daily sweeping and cleaning of the Premises.

     Tenant shall cooperate fully with Landlord at all times and abide by all
regulations and requirements that Landlord may reasonably prescribe for the
proper functioning and protection of the HVAC, electrical, mechanical and
plumbing systems.

     6.2  OVERSTANDARD TENANT USE.  Tenant shall not, without Landlord's prior
written consent, use heat-generating machines, machines other than normal
fractional horsepower office machines, or equipment or lighting other than
Building standard lights in the Premises, which may affect the temperature
otherwise maintained by the air conditioning system or increase the water
normally furnished for the Premises by Landlord pursuant to the terms of Section
6.1 of this Lease.  If Tenant uses water, electricity, heat or air conditioning
in excess of that supplied by Landlord pursuant to Section 6.1 of this Lease,
Tenant shall pay to Landlord, upon billing, the cost of such excess consumption,
the cost of the installation, operation, and maintenance of equipment which is
installed in order to supply such excess consumption, and the cost of the
increased wear and tear on existing equipment caused by such excess consumption;
and Landlord may install devices to separately meter any increased use and in
such event Tenant shall pay the increased cost directly to Landlord, on demand,
at the rates charged by the public utility company furnishing the same,
including the cost of such additional metering devices.  Tenant's use of
electricity shall never exceed the capacity of the feeders to the Project or the
risers or wiring installation.

     6.3  INTERRUPTION OF USE.  Tenant agrees that Landlord shall not be liable
for damages, by abatement of Rent or otherwise, for failure to furnish or delay
in furnishing any service (including telephone and telecommunication services),
or for any diminution in the quality or quantity thereof, when such failure or
delay or diminution is occasioned, in whole or in part, by

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breakage, repairs, replacements, or improvements, by any strike, lockout or
other labor trouble, by inability to secure electricity, gas, water, or other
fuel at the Building or Project after reasonable effort to do so, by any riot or
other dangerous condition, emergency, accident or casualty whatsoever, by act or
default of Tenant or other parties, or by any other cause beyond Landlord's
reasonable control; and such failures or delays or diminution shall never be
deemed to constitute an eviction or disturbance of Tenant's use and possession
of the Premises or relieve Tenant from paying Rent or performing any of its
obligations under this Lease. Furthermore, Landlord shall not be liable under
any circumstances for a loss of, or injury to, property (except, with respect to
property damage or personal injury only, to the extent caused by Landlord's
negligence or wilful misconduct) or for injury to, or interference with,
Tenant's business, including, without limitation, loss of profits, however
occurring, through or in connection with or incidental to a failure to furnish
any of the services or utilities as set forth in this Article 6.

     6.4  SUBMETERING UTILITIES.  In the event that the Premises are separately
metered for electricity, water, or any other utility service, Landlord shall
have the right to bill Tenant directly the cost of such utility, and Tenant
shall pay such costs directly to Landlord at the rates charged by the public
utility company furnishing the same, or to require Tenant to contract directly
with the applicable public utility for such service.  Any such costs paid by
Tenant or any other tenant of the Building shall not be included in Operating
Expenses.

                                   ARTICLE 7
                                   ---------

                            MAINTENANCE AND REPAIRS
                            -----------------------

     7.1  MAINTENANCE OBLIGATIONS.  Landlord shall maintain and repair the
structural portions of the Building, including the foundation, floor/ceiling
slabs, roof, curtain wall, exterior glass and mullions, columns, beams, shafts
(including elevator shafts), stairs, stairwells, and elevator cabs
(collectively, "Building Structure") and the mechanical, electrical, life
safety, plumbing, sprinkler systems and HVAC systems which are not part of the
"Tenant Improvements", as that term is defined in Section 2.1 of the Tenant Work
Letter (the "Building Systems").  Tenant shall, at Tenant's own expense, keep
the Premises, including all improvements, fixtures and furnishings therein, in
good order, repair and condition at all times during the Lease Term.  In
addition, Tenant shall, at Tenant's own expense, but under the supervision and
subject to the prior approval of Landlord, and within any reasonable period of
time specified by Landlord, promptly and adequately repair all damage to the
Premises and replace or repair all damaged, broken, or worn fixtures and
appurtenances, except for damage caused by ordinary wear and tear or beyond the
reasonable control of Tenant; provided however, that, at Landlord's option, or
if Tenant fails to make such repairs, Landlord may, but need not, make such
repairs and replacements, and Tenant shall pay Landlord the cost thereof,
including a percentage of the cost thereof (to be uniformly established for the
Project) sufficient to reimburse Landlord for all overhead, general conditions,
fees and other costs or expenses arising from Landlord's involvement with such
repairs and replacements forthwith upon being billed for same.  Landlord may,
but shall not be required to, enter the Premises at all reasonable times to make
such repairs, alterations, improvements or additions to the Premises or to the
Project or to any equipment located in the Project as Landlord shall desire or
deem necessary or as Landlord may

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be required to do by governmental or quasi-governmental authority or court order
or decree. Tenant hereby waives any and all rights under and benefits of
subsection 1 of Section 1932 and Sections 1941 and 1942 of the California Civil
Code or under any similar law, statute, or ordinance now or hereafter in effect.

     7.2  TENANT'S RIGHT TO MAKE REPAIRS.  In lieu of finding Landlord in
default under Section 19.6 of this Lease, if Tenant provides written notice to
Landlord of an event or circumstance which requires the action of Landlord
pursuant to the terms of this Lease, and Landlord fails to provide or commence
to provide (and thereafter make commercially reasonably good faith efforts to
diligently proceed with such efforts to completion), such action as required by
the terms of this Lease within twenty-five (25) days after receipt of such
written notice (or, in the event of an "Emergency," as that term is defined
below, two (2) business days), Tenant may proceed to take the required action
upon delivery of an additional five (5) business days (or in the case of an
Emergency, two (2) business days) notice to Landlord specifying that Tenant is
taking such required action, and if such action was required under the terms of
this Lease to be taken by Landlord, then Tenant shall be entitled to prompt
reimbursement by Landlord of Tenant's costs and expenses incurred in taking such
action during the period from the date Tenant incurs such costs and expenses
until such time as payment is made by Landlord.  For such work that affects the
Building structure, or the Building systems and equipment or the exterior
appearance of the Building, Tenant shall use only qualified contractors which
normally and regularly performs similar work in the Project.  Further, if
Landlord does not deliver a detailed written objection to Tenant within ten (10)
business days after receipt of an invoice from Tenant of its costs of taking
action which Tenant claims should have been taken by Landlord, which invoice
from Tenant sets forth a reasonably particularized breakdown of its costs and
expenses in connection with taking such action on behalf of Landlord, then
Tenant shall be entitled to deduct from Rent becoming payable by Tenant under
this Lease, the amount set forth in such invoice.  If, however, Landlord in good
faith delivers to Tenant, within ten (10) business days after receipt of
Tenant's invoice, a written objection to the payment of such invoice, setting
forth with reasonable particularity Landlord's reasons for its claim that such
action did not have to be taken by Landlord pursuant to the terms of this Lease
or that the charges are excessive (in which case Landlord shall pay,
concurrently with Landlord's delivery of such written objection, the amount it
contends would not have been excessive), then Tenant shall not be entitled to
such deduction from Rent, but Tenant may proceed to institute arbitration
proceedings against Landlord pursuant to the terms of Article 29.32, below, to
determine that portion, if any, of the amounts so incurred by Tenant which
Landlord is required to reimburse Tenant under this Section 7.2.  Tenant may
deduct the amount of any final, non-appealable arbitration award, not to exceed
the amount of the unpaid portion of the relevant invoice, together with interest
thereon at the Interest Rate from the Base Rent next due and owing under this
Lease.  For the purposes of this Section 7.2, the term "Emergency" shall mean a
condition that creates an imminent, material threat to life or of material
damage to property.

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                                   ARTICLE 8
                                   ---------

                           ADDITIONS AND ALTERATIONS
                           -------------------------

     8.1  LANDLORD'S CONSENT TO ALTERATIONS.  Tenant may not make any
improvements, alterations, additions or changes to the Premises or any
mechanical, plumbing or HVAC facilities or systems pertaining to the Premises
(collectively, the "ALTERATIONS") without first procuring the prior written
consent of Landlord to such Alterations, which consent shall be requested by
Tenant not less than thirty (30) days prior to the commencement thereof, and
which consent shall not be unreasonably withheld by Landlord, provided it shall
be deemed reasonable for Landlord to withhold its consent to any Alteration
which adversely affects the structural portions or the systems or equipment of
the Building or is visible from the exterior of the Building.  The term
"Alterations" shall not include the initial construction of the Tenant
Improvements in the Premises in accordance with the terms of the Tenant Work
Letter.  Notwithstanding the foregoing, Tenant shall have the right, without
Landlord's consent but upon five (5) business days prior notice to Landlord, to
make strictly non-structural additions and alterations ("Cosmetic Alterations")
to the Premises that do not (i) involve the expenditure of more than $5,000.00
in the aggregate, (ii) affect the exterior appearance of the Building, (iii)
affect the mechanical, electrical, life safety, plumbing, sprinkler systems and
HVAC systems in the Building or any structural portions of the Building, or (iv)
violate law.  The construction of the initial improvements to the Premises shall
be governed by the terms of the Tenant Work Letter and not the terms of this
Article 8.

     8.2  MANNER OF CONSTRUCTION.  Landlord may impose, as a condition of its
consent to any and all Alterations or repairs of the Premises or about the
Premises, made at the time of Tenant's request for such Alterations or repairs,
such requirements as Landlord in its sole discretion may deem desirable,
including, but not limited to, the requirement that Tenant utilize for such
purposes only contractors, subcontractors, materials, mechanics and materialmen
approved in advance by Landlord (which approval shall not be unreasonably
withheld), the requirement that upon Landlord's request, Tenant shall, at
Tenant's expense, remove such Alterations upon the expiration or any early
termination of the Lease Term.  Tenant shall construct such Alterations and
perform such repairs in a good and workmanlike manner, in conformance with any
and all applicable federal, state, county or municipal laws, rules and
regulations and pursuant to a valid building permit, issued by the City of
Irvine, all in conformance with Landlord's construction rules and regulations.
In the event Tenant performs any Alterations in the Premises which require or
give rise to governmentally required changes to the "Base Building," as that
term is defined below, then Landlord shall, at Tenant's expense, make such
changes to the Base Building.  The "BASE BUILDING" shall include the structural
portions of the Building, and the public restrooms and the systems and equipment
located in the internal core of the Building on the floor or floors on which the
Premises are located.  In performing the work of any such Alterations, Tenant
shall have the work performed in such manner so as not to obstruct access to the
Project or any portion thereof, by any other tenant of the Project, and so as
not to obstruct the business of Landlord or other tenants in the  Project.
Tenant shall not use (and upon notice from Landlord shall cease using)
contractors, services,

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workmen, labor, materials or equipment that, in Landlord's reasonable judgment,
would disturb labor harmony with the workforce or trades engaged in performing
other work, labor or services in or about the Building or the Common Areas. In
addition to Tenant's obligations under Article 9 of this Lease, upon completion
of any Alterations, Tenant agrees to cause a Notice of Completion to be recorded
in the office of the Recorder of the County of Orange in accordance with Section
3093 of the Civil Code of the State of California or any successor statute, and
Tenant shall deliver to the Project management office a reproducible copy of the
"as built" drawings of the Alterations as well as all permits, approvals and
other documents issued by any governmental agency in connection with the
Alterations.

     8.3  PAYMENT FOR IMPROVEMENTS.  If payment is made directly to contractors,
Tenant shall comply with Landlord's requirements for final lien releases and
waivers in connection with Tenant's payment for work to contractors.  Whether or
not Tenant orders any work directly from Landlord, Tenant shall pay to Landlord
a percentage (not to exceed 5%) of the cost of such work sufficient to
compensate Landlord for all overhead, general conditions, fees and other costs
and expenses arising from Landlord's involvement with such work.

     8.4  CONSTRUCTION INSURANCE.  In connection with the construction of any
Alterations, Tenant shall comply with the terms of Section 10.3.4 regarding
Tenant's and its agents' insurance obligations.

     8.5  LANDLORD'S PROPERTY.  All Alterations, improvements, fixtures and/or
appurtenances which may be installed or placed in or about the Premises, from
time to time, shall be at the sole cost of Tenant and shall be and become the
property of Landlord, except that Tenant may remove any Alterations,
improvements and/or fixtures which Tenant can substantiate to Landlord have not
been paid for with any Tenant improvement allowance funds provided to Tenant by
Landlord, provided Tenant repairs any damage to the Premises and Building caused
by such removal and returns the affected portion of the Premises to a building
standard tenant improved condition as determined by Landlord.  Furthermore, if
Landlord, as a condition to Landlord's consent to any Alteration, requires that
Tenant remove any Alteration upon the expiration or early termination of the
Lease Term, Landlord may, by written notice to Tenant prior to the end of the
Lease Term, or given following any earlier termination of this Lease, require
Tenant, at Tenant's expense, to remove such Alterations and to repair any damage
to the Premises and Building caused by such removal and returns the affected
portion of the Premises to a building standard tenant improved condition as
determined by Landlord.  If Tenant fails to complete such removal and/or to
repair any damage caused by the removal of any Alterations and returns the
affected portion of the Premises to a building standard tenant improved
condition as determined by Landlord, Landlord may do so and may charge the cost
thereof to Tenant.  Tenant hereby protects, defends, indemnifies and holds
Landlord harmless from any liability, cost, obligation, expense or claim of lien
in any manner relating to the installation, placement, removal or financing of
any such Alterations, improvements, fixtures and/or equipment in, on or about
the Premises, which obligations of Tenant shall survive the expiration or
earlier termination of this Lease.

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                                   ARTICLE 9
                                   ---------

                             COVENANT AGAINST LIENS
                             ----------------------

     Tenant shall keep the Project and Premises free from any liens or
encumbrances arising out of the work performed, materials furnished or
obligations incurred by or on behalf of Tenant, and shall protect, defend,
indemnify and hold Landlord harmless from and against any claims, liabilities,
judgments or costs (including, without limitation, reasonable attorneys' fees
and costs) arising out of same or in connection therewith.  Tenant shall give
Landlord notice at least twenty (20) days prior to the commencement of any such
work on the Premises (or such additional time as may be necessary under
applicable laws) to afford Landlord the opportunity of posting and recording
appropriate notices of non-responsibility.  Tenant shall remove any such lien or
encumbrance by bond or otherwise within five (5) days after notice by Landlord,
and if Tenant shall fail to do so, Landlord may pay the amount necessary to
remove such lien or encumbrance, without being responsible for investigating the
validity thereof.  The amount so paid shall be deemed Additional Rent under this
Lease payable upon demand, without limitation as to other remedies available to
Landlord under this Lease.  Nothing contained in this Lease shall authorize
Tenant to do any act which shall subject Landlord's title to the Building or
Premises to any liens or encumbrances whether claimed by operation of law or
express or implied contract.  Any claim to a lien or encumbrance upon the
Building or Premises arising in connection with any such work or respecting the
Premises not performed by or at the request of Landlord shall be null and void,
or at Landlord's option shall attach only against Tenant's interest in the
Premises and shall in all respects be subordinate to Landlord's title to the
Project, Building and Premises.

                                   ARTICLE 10
                                   ----------

                                   INSURANCE
                                   ---------

     10.1  INDEMNIFICATION AND WAIVER.  Except to the extent caused by the
negligence or wilful misconduct of Landlord, Tenant hereby assumes all risk of
damage to property or injury to persons in, upon or about the Premises from any
cause whatsoever and agrees that Landlord, its partners, subpartners and their
respective officers, agents, servants, employees, and independent contractors
(collectively, "LANDLORD PARTIES") shall not be liable for, and are hereby
released from any responsibility for, any damage either to person or property or
resulting from the loss of use thereof, which damage is sustained by Tenant or
by other persons claiming through Tenant.  Tenant shall indemnify, defend,
protect, and hold harmless the Landlord Parties from any and all loss, cost,
damage, expense and liability (including without limitation court costs and
reasonable attorneys' fees) incurred in connection with or arising from any
cause in, on or about the Premises, any acts, omissions or negligence of Tenant
or of any person claiming by, through or under Tenant, or of the contractors,
agents, servants, employees, invitees, guests or licensees of Tenant or any such
person (collectively, "TENANT PARTIES"), in, on or about the Project or any
breach of the terms of this Lease, either prior to, during, or after the
expiration of the Lease Term, provided that the terms of the foregoing indemnity
shall not apply to the negligence or willful misconduct of Landlord.  Landlord
shall indemnify, defend, protect, and hold harmless Tenant and the Tenant
Parties from any and all loss, cost, damage, expense and liability

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(including without limitation reasonable attorneys' fees) arising from the
negligence or wilful misconduct of the Landlord Parties in, on or about the
Project, except to the extent caused by the negligence or wilful misconduct of
the Tenant Parties. Notwithstanding anything to the contrary set forth in this
Lease, either party's agreement to indemnify the other party as set forth in
this Article 10, above, shall be ineffective to the extent the matters for which
such party agreed to indemnify the other party are covered by insurance required
to be carried by the other party pursuant to this Lease. Further, Tenant's
agreement to indemnify Landlord and Landlord's agreement to indemnify Tenant
pursuant to this Article 10 are not intended and shall not relieve any insurance
carrier of its obligations under policies required to be carried pursuant to the
provisions of this Lease, to the extent such policies cover subject to the
parties' respective indemnification obligations; nor shall they supersede any
inconsistent agreement of the parties set forth in any other provision of this
Lease. Should Landlord be named as a defendant in any suit brought against
Tenant in connection with or arising out of Tenant's occupancy of the Premises,
Tenant shall pay to Landlord its costs and expenses incurred in such suit,
including without limitation, its actual professional fees such as appraisers',
accountants' and attorneys' fees. In addition, Tenant shall pay to Landlord any
costs and expenses, including without limitation, its actual attorney's fees,
incurred by Landlord in successfully enforcing Tenant's indemnity obligations
set forth in this Section 10.1. The provisions of this Section 10.1 shall
survive the expiration or sooner termination of this Lease with respect to any
claims or liability arising in connection with any event occurring prior to such
expiration or termination.

     10.2  TENANT'S COMPLIANCE WITH LANDLORD'S PROPERTY AND CASUALTY INSURANCE.
Tenant shall, at Tenant's expense, comply with all insurance company
requirements pertaining to the use of the Premises.  If Tenant's conduct or use
of the Premises causes any increase in the premium for such insurance policies
then Tenant shall reimburse Landlord for any such increase.

     10.3  TENANT'S INSURANCE.  Tenant shall maintain the following coverages in
the following amounts.

          10.3.1  Commercial General Liability Insurance covering the insured
against claims of bodily injury, personal injury and property damage (including
loss of use thereof) arising out of Tenant's operations, actions, and
contractual liabilities (covering the performance by Tenant of its indemnity
agreements) including a Broad Form endorsement covering the insuring provisions
of this Lease and the performance by Tenant of the indemnity agreements set
forth in Section 10.1 of this Lease, for limits of liability (with a
commercially reasonable deductible) not less than:

     Bodily Injury                          $1,000,000 each occurrence
     Property Damage                        $10,000,000 annual aggregate
     and Personal Injury Liability

          10.3.2  All Risk Property Insurance covering (i) all office furniture,
business and trade fixtures, office equipment, free-standing cabinet work,
movable partitions, merchandise and all other items of Tenant's property on the
Premises installed by, for, or at the expense of Tenant, (ii) the "Tenant
Improvements", as that term is defined in Section 2.1 of the Tenant Work Letter

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and any other improvements which exist in the Premises as of the Lease
Commencement Date (excluding the Base Building) (the "ORIGINAL IMPROVEMENTS"),
(iii) the Tenant's business interruption and extra expense in an amount equal to
one (1) year of Rent due under this Lease and (iv) all other improvements,
alterations and additions to the Premises.  Such insurance shall be written on
an "all risks" of physical loss or damage basis, for the full replacement cost
value (subject to reasonable deductible amounts) and with an agreed amount
endorsement, and shall include coverage for damage or other loss caused by fire
or other peril including, but not limited to, vandalism and malicious mischief,
theft, water damage, including sprinkler leakage, earthquake sprinkler leakage,
bursting or stoppage of pipes, and explosion.

          10.3.3  Worker's Compensation and Employer's Liability in an amount no
less than $1,000,000.00 or other similar insurance pursuant to all applicable
state and local statutes and regulations.

          10.3.4  Prior to commencing any construction in the Premises, either
in connection with the initial construction of the Tenant Improvements, or in
connection with any Alterations, Tenant shall provide Landlord with evidence
that any contractors, subcontractors, architects or engineers engaged in such
construction carry insurance of the type and in the amount required to be
carried by Tenant pursuant to Sections 10.3.1 and 10.3.2, above.  In addition,
any general contractor's policy of insurance shall contain an owner's contractor
protective endorsement, and coverage for work performed by others, and any
contractors or subcontractors insurance shall contain products and completed
operations coverage and said contractor shall warrant that it shall continue to
carry such coverage for a period of not less than ten (10) years.  Any
architects or engineers engaged by Tenant in connection with any such
construction shall additionally carry errors and omissions insurance coverage.
In addition, Landlord may, in its discretion in connection with Alterations
costing in excess of $25,000, require that Tenant obtain a lien and completion
bond or some alternate form of security satisfactory to Landlord in an amount
sufficient to ensure the lien-free completion of such Alterations and naming
Landlord as a co-obligee.

     10.4  FORM OF POLICIES.  The minimum limits of policies of insurance
required of Tenant or its contractors, subcontractors, architects or engineers
under this Lease shall in no event limit the liability of Tenant under this
Lease.  Such insurance shall (i) as appropriate name Landlord, and any other
party the Landlord so specifies, as an additional insured, including Landlord's
managing agent, if any; (ii) specifically cover the liability assumed by Tenant
under this Lease, including, but not limited to, Tenant's obligations under
Section 10.1 of this Lease; (iii) be issued by an insurance company having a
rating of not less than A-X in Best's Insurance Guide or which is otherwise
acceptable to Landlord and licensed to do business in the State of California;
(iv)  be primary insurance as to all claims thereunder and provide that any
insurance carried by Landlord is excess and is non-contributing with any
insurance requirement of Tenant; (v) be in form and content reasonably
acceptable to Landlord; and (vi) provide that said insurance shall not be
canceled or coverage materially changed unless thirty (30) days' prior written
notice shall have been given to Landlord and any mortgagee of Landlord by the
insurer or the Tenant.  Tenant shall deliver said policy or policies or
certificates thereof to Landlord on or before the Lease Commencement Date and at
least thirty (30) days before the expiration dates

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thereof. In the event Tenant shall fail to procure such insurance, or to deliver
such policies or certificate, within five (5) business days after written demand
from Landlord, Landlord may, at its option, procure such policies for the
account of Tenant, and the cost thereof shall be paid to Landlord within five
(5) days after delivery to Tenant of bills therefor.

     10.5  SUBROGATION.  Landlord and Tenant intend that their respective
property loss risks shall be borne by reasonable insurance carriers to the
extent above provided, and Landlord and Tenant hereby agree to look solely to,
and seek recovery only from, their respective insurance carriers in the event of
a property loss.  The parties each hereby waive all rights and claims against
each other for such losses, and waive all rights of subrogation of their
respective insurers, provided such waiver of subrogation shall not affect the
right to the insured to recover thereunder.  The parties agree that their
respective insurance policies are now, or shall be, endorsed such that the
waiver of subrogation shall not affect the right of the insured to recover
thereunder, so long as no material additional premium is charged therefor.

     10.6  ADDITIONAL INSURANCE OBLIGATIONS.  Tenant shall carry and maintain
during the entire Lease Term, at Tenant's sole cost and expense, increased
amounts of the insurance required to be carried by Tenant pursuant to this
Article 10 and such other reasonable types of insurance coverage and in such
reasonable amounts covering the Premises and Tenant's operations therein, as may
be reasonably requested by Landlord.

                                   ARTICLE 11
                                   ----------

                             DAMAGE AND DESTRUCTION
                             ----------------------

     11.1  REPAIR OF DAMAGE TO PREMISES BY LANDLORD.  Tenant shall promptly
notify Landlord of any damage to the Premises resulting from fire or any other
loss.  If the Premises or any Common Areas serving or providing access to the
Premises shall be damaged by fire or other casualty, Landlord shall promptly and
diligently, subject to reasonable delays for insurance adjustment or other
matters beyond Landlord's reasonable control, and subject to all other terms of
this Article 11, restore the Base Building and such Common Areas.  Such
restoration shall be to substantially the same condition of the Base Building
and the Common Areas prior to the casualty, except for modifications required by
zoning and building codes and other laws or by the holder of a mortgage on the
Building or Project or any other modifications to the Common Areas deemed
desirable by Landlord, provided that access to the Premises and any common
restrooms serving the Premises shall not be materially impaired.  Upon the
occurrence of any damage to the Premises, Tenant shall assign to Landlord (or to
any party designated by Landlord) all insurance proceeds payable to Tenant under
Tenant's insurance required under Sections 10.3.2 (ii) and (iv) of this Lease,
and Landlord shall repair any injury or damage to the Tenant Improvements and
the Original Improvements installed in the Premises and shall return such Tenant
Improvements and Original Improvements to their original condition; provided
that if the cost of such repair by Landlord exceeds the amount of insurance
proceeds received by Landlord from Tenant's insurance carrier, as assigned by
Tenant, either (i) the cost of such repairs shall be paid by Tenant to Landlord
prior to Landlord's commencement of repair of the damage, or (ii) Landlord shall
rebuild the Premises only to the extent of insurance proceeds received.
Landlord shall not be

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liable for any inconvenience or annoyance to Tenant or its visitors, or injury
to Tenant's business resulting in any way from such damage or the repair
thereof; provided however, that if such fire or other casualty shall have
damaged the Premises or Common Areas necessary to Tenant's occupancy, Landlord
shall allow Tenant a proportionate abatement of Rent to the extent Landlord is
reimbursed from the proceeds of rental interruption insurance purchased by
Landlord as part of Operating Expenses, during the time and to the extent the
Premises are unfit for occupancy for the purposes permitted under this Lease,
and not occupied by Tenant as a result thereof; provided, further, however, that
if the damage or destruction is due to the negligence or wilful misconduct of
Tenant or any of its agents, employees, contractors, invitees or guests, Tenant
shall be responsible for any reasonable, applicable insurance deductible (which
shall be payable to Landlord upon demand) and there shall be no rent abatement.

     11.2  LANDLORD'S OPTION TO REPAIR.  Notwithstanding the terms of Section
11.1 of this Lease, Landlord may elect not to rebuild and/or restore the
Premises, Building and/or Project, and instead terminate this Lease, by
notifying Tenant in writing of such termination within sixty (60) days after the
date of the discovery of damage, such notice to include a termination date
giving Tenant sixty (60) days to vacate the Premises, but Landlord may so elect
only if the Building or Project shall be damaged by fire or other casualty or
cause, whether or not the Premises are affected, and one or more of the
following conditions is present: (i) in Landlord's reasonable judgment, repairs
cannot reasonably be completed within ninety (90) days (or in the event of
damage resulting from earthquake, three hundred sixty (360) days) after the date
of damage (when such repairs are made without the payment of overtime or other
premiums); (ii) the holder of any mortgage on the Building or Project or ground
lessor with respect to the Building or Project shall require that the insurance
proceeds or any portion thereof be used to retire the mortgage debt, or shall
terminate the ground lease, as the case may be; (iii) the damage is not fully
covered, except for deductible amounts, by Landlord's insurance policies; (iv)
Landlord decides to rebuild the Building or Common Areas so that they will be
substantially different structurally or architecturally; (v) the damage occurs
during the last twelve (12) months of the Lease Term; or (vi) any owner of any
other portion of the Project, other than Landlord, does not intend to repair the
damage to such portion of the Project.  If Landlord does not elect to terminate
this Lease pursuant to Landlord's termination right as provided above, and the
repairs cannot, in the reasonable opinion of an architect or contractor selected
by Landlord and reasonably approved by Tenant, be completed within one (1) year
after being commenced, Tenant may elect, no earlier than sixty (60) days after
the date of the damage and not later than ninety (90) days after the date of
such damage, to terminate this Lease by written notice to Landlord effective as
of the date specified in the notice.

     11.3  WAIVER OF STATUTORY PROVISIONS.  The provisions of this Lease,
including this Article 11, constitute an express agreement between Landlord and
Tenant with respect to any and all damage to, or destruction of, all or any part
of the Premises, the Building or the Project, and any statute or regulation of
the State of California, including, without limitation, Sections 1932(2) and
1933(4) of the California Civil Code, with respect to any rights or obligations
concerning damage or destruction in the absence of an express agreement between
the parties, and any other statute or regulation, now or hereafter in effect,
shall have no

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application to this Lease or any damage or destruction to all or any part of the
Premises, the Building or the Project.

                                   ARTICLE 12
                                   ----------

                                   NONWAIVER
                                   ---------

     No provision of this Lease shall be deemed waived by either party hereto
unless expressly waived in a writing signed thereby.  The waiver by either party
hereto of any breach of any term, covenant or condition herein contained shall
not be deemed to be a waiver of any subsequent breach of same or any other term,
covenant or condition herein contained.  The subsequent acceptance of Rent
hereunder by Landlord shall not be deemed to be a waiver of any preceding breach
by Tenant of any term, covenant or condition of this Lease, other than the
failure of Tenant to pay the particular Rent so accepted, regardless of
Landlord's knowledge of such preceding breach at the time of acceptance of such
Rent.  No acceptance of a lesser amount than the Rent herein stipulated shall be
deemed a waiver of Landlord's right to receive the full amount due, nor shall
any endorsement or statement on any check or payment or any letter accompanying
such check or payment be deemed an accord and satisfaction, and Landlord may
accept such check or payment without prejudice to Landlord's right to recover
the full amount due.  No receipt of monies by Landlord from Tenant after the
termination of this Lease shall in any way alter the length of the Lease Term or
of Tenant's right of possession hereunder, or after the giving of any notice
shall reinstate, continue or extend the Lease Term or affect any notice given
Tenant prior to the receipt of such monies, it being agreed that after the
service of notice or the commencement of a suit, or after final judgment for
possession of the Premises, Landlord may receive and collect any Rent due, and
the payment of said Rent shall not waive or affect said notice, suit or
judgment.

                                   ARTICLE 13
                                   ----------

                                  CONDEMNATION
                                  ------------

     If the whole or any part of the Premises, Building or Project shall be
taken by power of eminent domain or condemned by any competent authority for any
public or quasi-public use or purpose, or if any adjacent property or street
shall be so taken or condemned, or reconfigured or vacated by such authority in
such manner as to require the use, reconstruction or remodeling of any part of
the Premises, Building or Project, or if Landlord shall grant a deed or other
instrument in lieu of such taking by eminent domain or condemnation, Landlord
shall have the option to terminate this Lease effective as of the date
possession is required to be surrendered to the authority.  If more than twenty-
five percent (25%) of the rentable square feet of the Premises is taken, or if
access to the Premises is substantially impaired, in each case for a period in
excess of one hundred eighty (180) days, Tenant shall have the option to
terminate this Lease effective as of the date possession is required to be
surrendered to the authority.  Tenant shall not because of such taking assert
any claim against Landlord or the authority for any compensation because of such
taking and Landlord shall be entitled to the entire award or payment in
connection therewith, except that Tenant shall have the right to file any
separate claim available to Tenant

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for any taking of Tenant's personal property and fixtures belonging to Tenant
and removable by Tenant upon expiration of the Lease Term pursuant to the terms
of this Lease, for moving expenses, and for any loss of business or business
interruption or "goodwill," so long as such claim is payable separately to
Tenant. All Rent shall be apportioned as of the date of such termination. If any
part of the Premises shall be taken, and this Lease shall not be so terminated,
the Rent shall be proportionately abated. Tenant hereby waives any and all
rights it might otherwise have pursuant to Section 1265.130 of The California
Code of Civil Procedure. Notwithstanding anything to the contrary contained in
this Article 13, in the event of a temporary taking of all or any portion of the
Premises for a period of one hundred and eighty (180) days or less, then this
Lease shall not terminate but the Base Rent and the Additional Rent shall be
abated for the period of such taking in proportion to the ratio that the amount
of rentable square feet of the Premises taken bears to the total rentable square
feet of the Premises. Landlord shall be entitled to receive the entire award
made in connection with any such temporary taking.

                                   ARTICLE 14
                                   ----------

                           ASSIGNMENT AND SUBLETTING
                           -------------------------

     14.1  TRANSFERS.  Tenant shall not, without the prior written consent of
Landlord, assign, mortgage, pledge, hypothecate, encumber, or permit any lien to
attach to, or otherwise transfer, this Lease or any interest hereunder, permit
any assignment, or other transfer of this Lease or any interest hereunder by
operation of law, sublet the Premises or any part thereof, or enter into any
license or concession agreements or otherwise permit the occupancy or use of the
Premises or any part thereof by any persons other than Tenant and its employees
and contractors (all of the foregoing are hereinafter sometimes referred to
collectively as "TRANSFERS" and any person to whom any Transfer is made or
sought to be made is hereinafter sometimes referred to as a "TRANSFEREE").  If
Tenant desires Landlord's consent to any Transfer, Tenant shall notify Landlord
in writing, which notice (the "TRANSFER NOTICE") shall include (i) the proposed
effective date of the Transfer, which shall not be less than thirty (30) days
nor more than one hundred eighty (180) days after the date of delivery of the
Transfer Notice, (ii) a description of the portion of the Premises to be
transferred (the "SUBJECT SPACE"), (iii) all of the terms of the proposed
Transfer and the consideration therefor, including calculation of the "Transfer
Premium", as that term is defined in Section 14.3 below, in connection with such
Transfer, the name and address of the proposed Transferee, and a copy of all
existing executed and/or proposed documentation pertaining to the proposed
Transfer, including all existing operative documents to be executed to evidence
such Transfer or the agreements incidental or related to such Transfer, provided
that Landlord shall have the right to require Tenant to utilize Landlord's
standard Transfer documents in connection with the documentation of such
Transfer and (iv) financial statements for the prior two (2) fiscal years of the
proposed Transferee certified by an officer, partner or owner thereof, business
credit and personal references and history of the proposed Transferee and any
other information required by Landlord which will enable Landlord to determine
the financial responsibility, character, and reputation of the proposed
Transferee, nature of such Transferee's business and proposed use of the Subject
Space.  Any Transfer made without Landlord's prior written consent shall, at
Landlord's option, be null, void and of no

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effect, and shall, at Landlord's option, constitute a default by Tenant under
this Lease. Whether or not Landlord consents to any proposed Transfer, Tenant
shall pay Landlord's review and processing fees, as well as any reasonable
professional fees (including, without limitation, attorneys', accountants',
architects', engineers' and consultants' fees) incurred by Landlord, within
thirty (30) days after written request by Landlord.

     14.2  LANDLORD'S CONSENT.  Landlord shall not unreasonably withhold its
consent to any proposed Transfer of the Subject Space to the Transferee on the
terms specified in the Transfer Notice.  Without limitation as to other
reasonable grounds for withholding consent, the parties hereby agree that it
shall be reasonable under this Lease and under any applicable law for Landlord
to withhold consent to any proposed Transfer where one or more of the following
apply:

          14.2.1  The Transferee is of a character or reputation or engaged in a
business which is not consistent with the quality of the Project, or would be a
significantly less prestigious occupant of the Building than Tenant;

          14.2.2  The Transferee intends to use the Subject Space for purposes
which are not permitted under this Lease;

          14.2.3  The Transferee is either a governmental agency or
instrumentality thereof;

          14.2.4  The Transferee is not a party of reasonable financial worth
and/or financial stability in light of the responsibilities to be undertaken in
connection with the Transfer on the date consent is requested;

          14.2.5  The proposed Transfer would cause a violation of another lease
for space in the Project, or would give an occupant of the Project a right to
cancel its lease;

          14.2.6  The terms of the proposed Transfer will allow the Transferee
to exercise a right of renewal, right of expansion, right of first offer, or
other similar right held by Tenant (or will allow the Transferee to occupy space
leased by Tenant pursuant to any such right); or

          14.2.7  Either the proposed Transferee, or any person or entity which
directly or indirectly, controls, is controlled by, or is under common control
with, the proposed Transferee, is negotiating or has negotiated with Landlord to
lease space in the Project.

     If Landlord consents to any Transfer pursuant to the terms of this Section
14.2 (and does not exercise any recapture rights Landlord may have under Section
14.4 of this Lease), Tenant may within six (6) months after Landlord's consent,
but not later than the expiration of said six-month period, enter into such
Transfer of the Premises or portion thereof, upon substantially the same terms
and conditions as are set forth in the Transfer Notice furnished by Tenant to
Landlord pursuant to Section 14.1 of this Lease, provided that if there are any
changes in the terms and conditions from those specified in the Transfer Notice
(i) such that Landlord would initially have been entitled to refuse its consent
to such Transfer under this Section 14.2, or (ii) which would cause the proposed
Transfer to be more favorable to the Transferee than the terms set forth in

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Tenant's original Transfer Notice, Tenant shall again submit the Transfer to
Landlord for its approval and other action under this Article 14 (including
Landlord's right of recapture, if any, under Section 14.4 of this Lease).
Notwithstanding anything to the contrary in this Lease, if Tenant or any
proposed Transferee claims that Landlord has unreasonably withheld or delayed
its consent under Section 14.2 or otherwise has breached or acted unreasonably
under this Article 14, their sole remedies shall be a declaratory judgment and
an injunction for the relief sought without any monetary damages, and Tenant
hereby waives all other remedies, including, without limitation, any right at
law or equity to terminate this Lease, on its own behalf and, to the extent
permitted under all applicable laws, on behalf of the proposed Transferee.

     14.3  TRANSFER PREMIUM.  If Landlord consents to a Transfer, as a condition
thereto which the parties hereby agree is reasonable, Tenant shall pay to
Landlord fifty percent (50%) of any "Transfer Premium," as that term is defined
in this Section 14.3, received by Tenant from such Transferee.  "TRANSFER
PREMIUM" shall mean all rent, additional rent or other consideration payable by
such Transferee in connection with the Transfer in excess of the Rent and
Additional Rent payable by Tenant under this Lease during the term of the
Transfer on a per rentable square foot basis if less than all of the Premises is
transferred, after deducting the reasonable expenses incurred by Tenant for (i)
any changes, alterations and improvements to the Premises in connection with the
Transfer, (ii) any free base rent reasonably provided to the Transferee, and
(iii) any brokerage commissions in connection with the Transfer (collectively,
"TENANT'S SUBLEASING COSTS").  "Transfer Premium" shall also include, but not be
limited to, key money, bonus money or other cash consideration paid by
Transferee to Tenant in connection with such Transfer, and any payment in excess
of fair market value for services rendered by Tenant to Transferee or for
assets, fixtures, inventory, equipment, or furniture transferred by Tenant to
Transferee in connection with such Transfer.  The determination of the amount of
Landlord's applicable share of the Transfer Premium shall be made on a monthly
basis as rent or other consideration is received by Tenant under the Transfer.
For purposes of calculating the Transfer Premium on a monthly basis, (i)
Tenant's Subleasing Costs shall be deemed to be expended by Tenant in equal
monthly amounts over the entire term of the Transfer and (ii) the Rent paid for
the Subject Space by Tenant shall be computed after adjusting such rent to the
actual effective rent to be paid, taking into consideration any and all
leasehold concessions granted in connection therewith, including, but not
limited to, any rent credit and tenant improvement allowance.  For purposes of
calculating any such effective rent all such concessions shall be amortized on a
straight-line basis over the relevant term.

     14.4  LANDLORD'S OPTION AS TO SUBJECT SPACE.  Notwithstanding anything to
the contrary contained in this Article 14, Landlord shall have the option, by
giving written notice to Tenant within thirty (30) days after receipt of any
Transfer Notice, to recapture the Subject Space.  Such recapture notice shall
cancel and terminate this Lease with respect to the Subject Space as of the date
stated in the Transfer Notice as the effective date of the proposed Transfer
until the last day of the term of the Transfer as set forth in the Transfer
Notice (or at Landlord's option, shall cause the Transfer to be made to Landlord
or its agent, in which case the parties shall execute the Transfer documentation
promptly thereafter).  In the event of a recapture by Landlord, if this Lease
shall be canceled with respect to less than the entire Premises, the Rent

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reserved herein shall be prorated on the basis of the number of rentable square
feet retained by Tenant in proportion to the number of rentable square feet
contained in the Premises, and this Lease as so amended shall continue
thereafter in full force and effect, and upon request of either party, the
parties shall execute written confirmation of the same.  If Landlord declines,
or fails to elect in a timely manner to recapture the Subject Space under this
Section 14.4, then, provided Landlord has consented to the proposed Transfer,
Tenant shall be entitled to proceed to transfer the Subject Space to the
proposed Transferee, subject to provisions of this Article 14.

     14.5  EFFECT OF TRANSFER.  If Landlord consents to a Transfer, (i) the
terms and conditions of this Lease shall in no way be deemed to have been waived
or modified, (ii) such consent shall not be deemed consent to any further
Transfer by either Tenant or a Transferee, (iii) Tenant shall deliver to
Landlord, promptly after execution, an original executed copy of all
documentation pertaining to the Transfer in form reasonably acceptable to
Landlord, (iv) Tenant shall furnish upon Landlord's request a complete
statement, certified by an independent certified public accountant, or Tenant's
chief financial officer, setting forth in detail the computation of any Transfer
Premium Tenant has derived and shall derive from such Transfer, and (v) no
Transfer relating to this Lease or agreement entered into with respect thereto,
whether with or without Landlord's consent, shall relieve Tenant or any
guarantor of the Lease from any liability under this Lease, including, without
limitation, in connection with the Subject Space.  Landlord or its authorized
representatives shall have the right at all reasonable times to audit the books,
records and papers of Tenant relating to any Transfer, and shall have the right
to make copies thereof.  If the Transfer Premium respecting any Transfer shall
be found understated, Tenant shall, within thirty (30) days after demand, pay
the deficiency, and if understated by more than two percent (2%), Tenant shall
pay Landlord's costs of such audit.

     14.6  ADDITIONAL TRANSFERS.  For purposes of this Lease, the term
"TRANSFER" shall also include (i) if Tenant is a partnership, the withdrawal or
change, voluntary, involuntary or by operation of law, of fifty percent (50%) or
more of the partners, or transfer of fifty percent (50%) or more of partnership
interests, within a twelve (12)-month period, or the dissolution of the
partnership without immediate reconstitution thereof, and (ii) if Tenant is a
closely held corporation (i.e., whose stock is not publicly held and not traded
through an exchange or over the counter), (A) the dissolution, merger,
consolidation or other reorganization of Tenant or (B) the sale or other
transfer of an aggregate of fifty percent (50%) or more of the voting shares of
Tenant (other than to immediate family members by reason of gift or death),
within a twelve (12)-month period, or (C) the sale, mortgage, hypothecation or
pledge of an aggregate of fifty percent (50%) or more of the value of the
unencumbered assets of Tenant within a twelve (12)-month period.

     14.7  OCCURRENCE OF DEFAULT.  Any Transfer hereunder shall be subordinate
and subject to the provisions of this Lease, and if this Lease shall be
terminated during the term of any Transfer, Landlord shall have the right to:
(i) treat such Transfer as cancelled and repossess the Subject Space by any
lawful means, or (ii) require that such Transferee attorn to and recognize
Landlord as its landlord under any such Transfer.  If Tenant shall be in default
under this Lease, Landlord is hereby irrevocably authorized, as Tenant's agent
and attorney-in-fact, to direct any Transferee to make all payments under or in
connection with the Transfer directly to Landlord

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(which Landlord shall apply towards Tenant's obligations under this Lease) until
such default is cured. Such Transferee shall rely on any representation by
Landlord that Tenant is in default hereunder, without any need for confirmation
thereof by Tenant. Upon any assignment, the assignee shall assume in writing all
obligations and covenants of Tenant thereafter to be performed or observed under
this Lease. No collection or acceptance of rent by Landlord from any Transferee
shall be deemed a waiver of any provision of this Article 14 or the approval of
any Transferee or a release of Tenant from any obligation under this Lease,
whether theretofore or thereafter accruing. In no event shall Landlord's
enforcement of any provision of this Lease against any Transferee be deemed a
waiver of Landlord's right to enforce any term of this Lease against Tenant or
any other person. If Tenant's obligations hereunder have been guaranteed,
Landlord's consent to any Transfer shall not be effective unless the guarantor
also consents to such Transfer.

     14.8  NON-TRANSFERS.  Notwithstanding anything to the contrary contained in
Article 14 of this Lease, an assignment or subletting of all or a portion of the
Premises to an affiliate of Tenant (an entity which is controlled by, controls,
or is under common control with, Tenant, or which results from a merger with
Tenant, or which has purchased Tenant or substantially all of Tenant's assets),
shall not be deemed a Transfer under Article 14 of this Lease, provided that
Tenant notifies Landlord of any such assignment or sublease and promptly
supplies Landlord with any documents or information requested by Landlord
regarding such assignment or sublease or such affiliate, and further provided
that such assignment or sublease is not a subterfuge by Tenant to avoid its
obligations under this Lease.  "Control," as used in this Section 14.8, shall
mean the ownership, directly or indirectly, of at least fifty-one percent (51%)
of the voting securities of, or possession of the right to vote, in the ordinary
direction of its affairs, of at least fifty-one percent (51%) of the voting
interest in, an person or entity.

                                   ARTICLE 15
                                   ----------

                      SURRENDER OF PREMISES; OWNERSHIP AND
                      ------------------------------------
                           REMOVAL OF TRADE FIXTURES
                           -------------------------

     15.1  SURRENDER OF PREMISES.  No act or thing done by Landlord or any agent
or employee of Landlord during the Lease Term shall be deemed to constitute an
acceptance by Landlord of a surrender of the Premises unless such intent is
specifically acknowledged in writing by Landlord.  The delivery of keys to the
Premises to Landlord or any agent or employee of Landlord shall not constitute a
surrender of the Premises or effect a termination of this Lease, whether or not
the keys are thereafter retained by Landlord, and notwithstanding such delivery
Tenant shall be entitled to the return of such keys at any reasonable time upon
request until this Lease shall have been properly terminated.  The voluntary or
other surrender of this Lease by Tenant, whether accepted by Landlord or not, or
a mutual termination hereof, shall not work a merger, and at the option of
Landlord shall operate as an assignment to Landlord of all subleases or
subtenancies affecting the Premises or terminate any or all such sublessees or
subtenancies.

     15.2  REMOVAL OF TENANT PROPERTY BY TENANT.  Upon the expiration of the
Lease Term, or upon any earlier termination of this Lease, Tenant shall, subject
to the provisions of this

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Article 15, quit and surrender possession of the Premises to Landlord in as good
order and condition as when Tenant took possession and as thereafter improved by
Landlord and/or Tenant, reasonable wear and tear and repairs which are
specifically made the responsibility of Landlord hereunder excepted. Upon such
expiration or termination, Tenant shall, without expense to Landlord, remove or
cause to be removed from the Premises all debris and rubbish, and such items of
furniture, equipment, business and trade fixtures, free-standing cabinet work,
movable partitions and other articles of personal property owned by Tenant or
installed or placed by Tenant at its expense in the Premises, and such similar
articles of any other persons claiming under Tenant, as Landlord may, in its
sole discretion, require to be removed, and Tenant shall repair at its own
expense all damage to the Premises and Building resulting from such removal.

                                   ARTICLE 16
                                   ----------

                                  HOLDING OVER
                                  ------------

     If Tenant holds over after the expiration of the Lease Term or earlier
termination thereof, with or without the express or implied consent of Landlord,
such tenancy shall be from month-to-month only, and shall not constitute a
renewal hereof or an extension for any further term, and in such case Rent shall
be payable at a monthly rate equal to 200% of the Rent applicable during the
last rental period of the Lease Term under this Lease.  Such month-to-month
tenancy shall be subject to every other applicable term, covenant and agreement
contained herein.  Nothing contained in this Article 16 shall be construed as
consent by Landlord to any holding over by Tenant, and Landlord expressly
reserves the right to require Tenant to surrender possession of the Premises to
Landlord as provided in this Lease upon the expiration or other termination of
this Lease.  The provisions of this Article 16 shall not be deemed to limit or
constitute a waiver of any other rights or remedies of Landlord provided herein
or at law.  If Tenant fails to surrender the Premises upon the termination or
expiration of this Lease, in addition to any other liabilities to Landlord
accruing therefrom, Tenant shall protect, defend, indemnify and hold Landlord
harmless from all loss, costs (including reasonable attorneys' fees) and
liability resulting from such failure, including, without limiting the
generality of the foregoing, any claims made by any succeeding tenant founded
upon such failure to surrender and any lost profits to Landlord resulting
therefrom.

                                   ARTICLE 17
                                   ----------

                             ESTOPPEL CERTIFICATES
                             ---------------------

     Within ten (10) days following a request in writing by Landlord, Tenant
shall execute, acknowledge and deliver to Landlord an estoppel certificate,
which, as submitted by Landlord, shall be substantially in the form of EXHIBIT
E, attached hereto (or such other form as may be required by any prospective
mortgagee or purchaser of the Project, or any portion thereof), indicating
therein any exceptions thereto that may exist at that time, and shall also
contain any other information reasonably requested by Landlord or Landlord's
mortgagee or prospective mortgagee.  Any such certificate may be relied upon by
any prospective mortgagee or purchaser of all or any portion of the Project.
Tenant shall execute and deliver whatever other instruments

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may be reasonably required for such purposes within ten (10) days after receipt
of a request by Landlord. At any time during the Lease Term, and provided that
Landlord agrees in writing to keep the same reasonably confidential, Landlord
may require Tenant to provide Landlord within ten (10) days after receipt of a
request by Landlord with a current financial statement and financial statements
of the two (2) years prior to the current financial statement year. Such
statements shall be prepared in accordance with generally accepted accounting
principles and, if such is the normal practice of Tenant, shall be audited by an
independent certified public accountant. Failure of Tenant to timely execute,
acknowledge and deliver such estoppel certificate or other instruments shall
constitute an acceptance of the Premises and an acknowledgment by Tenant that
statements included in the estoppel certificate are true and correct, without
exception.

                                   ARTICLE 18
                                   ----------

                                 SUBORDINATION
                                 -------------

     Landlord agrees that it shall use reasonable efforts to obtain a
commercially reasonable non-disturbance and attornment agreement in favor of
Tenant from the currently existing trust deed holder on the Project.  This Lease
shall be subject and subordinate to all present and future ground or underlying
leases of the Building or Project and to the lien of any mortgage, trust deed or
other encumbrances now or hereafter in force against the Building or Project or
any part thereof, if any, and to all renewals, extensions, modifications,
consolidations and replacements thereof, and to all advances made or hereafter
to be made upon the security of such mortgages or trust deeds, unless the
holders of such mortgages, trust deeds or other encumbrances, or the lessors
under such ground lease or underlying leases (collectively, "MORTGAGEES"),
require in writing that this Lease be superior thereto.  Landlord agrees that it
shall use reasonable efforts to obtain a commercially reasonable non-disturbance
agreement from any existing Mortgagees in favor of Tenant.  Tenant covenants and
agrees in the event any proceedings are brought for the foreclosure of any such
mortgage or deed in lieu thereof (or if any ground lease is terminated), to
attorn, without any deductions or set-offs whatsoever, to the lienholder or
purchaser or any successors thereto upon any such foreclosure sale or deed in
lieu thereof (or to the ground lessor), if so requested to do so by such
purchaser or lienholder or ground lessor, and to recognize such purchaser or
lienholder or ground lessor as the lessor under this Lease, provided such
lienholder or purchaser or ground lessor shall agree to accept this Lease and
not disturb Tenant's occupancy, so long as Tenant timely pays the rent and
observes and performs the terms, covenants and conditions of this Lease to be
observed and performed by Tenant.  Landlord's interest herein may be assigned as
security at any time to any lienholder.  Tenant shall, within five (5) days of
request by Landlord, execute such further instruments or assurances as Landlord
may reasonably deem necessary to evidence or confirm the subordination or
superiority of this Lease to any such mortgages, trust deeds, ground leases or
underlying leases.  Tenant waives the provisions of any current or future
statute, rule or law which may give or purport to give Tenant any right or
election to terminate or otherwise adversely affect this Lease and the
obligations of the Tenant hereunder in the event of any foreclosure proceeding
or sale.

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                                   ARTICLE 19
                                   ----------

                               DEFAULTS; REMEDIES
                               ------------------

     19.1 EVENTS OF DEFAULT.  The occurrence of any of the following shall
constitute a default of this Lease by Tenant:

          19.1.1  Any failure by Tenant to pay any Rent or any other charge
required to be paid under this Lease, or any part thereof, when due unless such
failure is cured within three (3) days after notice; or

          19.1.2  Except where a specific time period is otherwise set forth for
Tenant's performance in this Lease, in which event the failure to perform by
Tenant within such time period shall be a default by Tenant under this Section
19.1.2, any failure by Tenant to observe or perform any other provision,
covenant or condition of this Lease to be observed or performed by Tenant where
such failure continues for ten (10) days after written notice thereof from
Landlord to Tenant; provided that if the nature of such default is such that the
same cannot reasonably be cured within a ten (10) day period, Tenant shall not
be deemed to be in default if it diligently commences such cure within such
period and thereafter diligently proceeds to rectify and cure such default, but
in no event exceeding a period of time in excess of thirty (30) days after
written notice thereof from Landlord to Tenant (which 30-day period shall be
extended for any Force Majeure) unless the nature of Tenant's obligation is such
that more than thirty (30) days are required for its performance, in which case
Tenant shall not be in default under this Lease if it shall commence such
performance within such thirty (30) day period and thereafter diligently pursue
the same to completion; or

          19.1.3  Abandonment or vacation of any material portion of the
Premises by Tenant other than in the normal course of business for company
holidays; or

          19.1.4  The failure by Tenant to observe or perform according to the
provisions of Articles 5, 14, 17 or 18 of this Lease where such failure
continues for more than five (5) business days after notice from Landlord; or

          19.1.5  Tenant's failure to occupy the Premises within thirty (30)
days after the Lease Commencement Date.

     The notice periods provided herein are in lieu of, and not in addition to,
any notice periods provided by law.

     19.2  REMEDIES UPON DEFAULT.  Upon the occurrence of any event of default
by Tenant, Landlord shall have, in addition to any other remedies available to
Landlord at law or in equity (all of which remedies shall be distinct, separate
and cumulative), the option to pursue any one or more of the following remedies,
each and all of which shall be cumulative and nonexclusive, without any notice
or demand whatsoever.

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          19.2.1  Terminate this Lease, in which event Tenant shall immediately
surrender the Premises to Landlord, and if Tenant fails to do so, Landlord may,
without prejudice to any other remedy which it may have for possession or
arrearages in rent, enter upon and take possession of the Premises and expel or
remove Tenant and any other person who may be occupying the Premises or any part
thereof, without being liable for prosecution or any claim or damages therefor;
and Landlord may recover from Tenant the following:

               (i)  The worth at the time of any unpaid rent which has been
     earned at the time of such termination; plus

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

               (iii) The worth at the time of award of the amount by which the
     unpaid rent for the balance of the Lease Term after the time of award
     exceeds the amount of such rental loss that Tenant proves could have been
     reasonably avoided; plus

               (iv) Any other amount necessary to compensate Landlord for all
     the detriment proximately caused by Tenant's failure to perform its
     obligations under this Lease or which in the ordinary course of things
     would be likely to result therefrom; and

               (v)  At Landlord's election, such other amounts in addition to or
     in lieu of the foregoing as may be permitted from time to time by
     applicable law.

     The term "rent" as used in this Section 19.2 shall be deemed to be and to
mean all sums of every nature required to be paid by Tenant to Landlord pursuant
to the terms of this Lease.  As used in Paragraphs 19.2.1(i) and (ii), above,
the "worth at the time of award" shall be computed by allowing interest at the
rate set forth in Article 25 of this Lease, but in no case greater than the
maximum amount of such interest permitted by law.  As used in Paragraph
19.2.1(iii) above, the "worth at the time of award" shall be computed by
discounting such amount at the discount rate of the Federal Reserve Bank of San
Francisco at the time of award plus one percent (1%).  If Landlord terminates
this Lease or Tenant's right to possession, Landlord shall use reasonable
efforts to mitigate Landlord's damages, and Tenant shall be entitled to submit
proof of such failure to mitigate as a defense to Landlord's claims hereunder,
if mitigation of damages by Landlord is required by applicable law.

          19.2.2  Landlord shall have the remedy described in California Civil
Code Section 1951.4 (lessor may continue lease in effect after lessee's breach
and abandonment and recover rent as it becomes due, if lessee has the right to
sublet or assign, subject only to reasonable limitations).  Accordingly, if
Landlord does not elect to terminate this Lease on account of any default by
Tenant, Landlord may, from time to time, without terminating this Lease, enforce
all of its rights and remedies under this Lease, including the right to recover
all rent as it becomes due.

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          19.2.3  Landlord shall at all times have the rights and remedies
(which shall be cumulative with each other and cumulative and in addition to
those rights and remedies available under Sections 19.2.1 and 19.2.2, above, or
any law or other provision of this Lease), without prior demand or notice except
as required by applicable law, to seek any declaratory, injunctive or other
equitable relief, and specifically enforce this Lease, or restrain or enjoin a
violation or breach of any provision hereof.

     19.3  FORM OF PAYMENT AFTER DEFAULT.  Following the occurrence of more than
two (2) events of default by Tenant in any twelve (12) month period, Landlord
shall have the right to require that any or all subsequent amounts paid by
Tenant to Landlord hereunder, whether to cure the default in question or
otherwise, be paid in the form of cash, money order, cashier's or certified
check drawn on an institution acceptable to Landlord, or by other means approved
by Landlord, notwithstanding any prior practice of accepting payments in any
different form.

     19.4  EFFORTS TO RELET.  No re-entry or repossession, repairs, maintenance,
changes, alterations and additions, reletting, appointment of a receiver to
protect Landlord's interests hereunder, or any other action or omission by
Landlord shall be construed as an election by Landlord to terminate this Lease
or Tenant's right to possession, or to accept a surrender of the Premises, nor
shall same operate to release Tenant in whole or in part from any of Tenant's
obligations hereunder, unless express written notice of such intention is sent
by Landlord to Tenant.  Tenant hereby irrevocably waives any right otherwise
available under any law to redeem or reinstate this Lease.

     19.5  ABATEMENT OF RENT.  In the event that Tenant is prevented from using,
and does not use, the Premises or any portion thereof, as a result of (i) any
alteration performed by Landlord after the Lease Commencement Date and required
by the Lease, which substantially interferes with Tenant's use of the Premises,
or (ii) any failure to provide services, utilities or access to the Premises as
required of Landlord pursuant to the terms hereof (either such set of
circumstances as set forth in items (i) or (ii), above, to be known as an
"ABATEMENT EVENT"), then Tenant shall give Landlord notice of such Abatement
Event, and if such Abatement Event continues for three (3) consecutive business
days after Landlord's  receipt of any such notice (the "ELIGIBILITY PERIOD"),
then the Base Rent and Tenant's Share of Building Direct Expenses shall be
abated or reduced, as the case may be, after expiration of the Eligibility
Period for such time that Tenant continues to be so prevented from using, and
does not use, the Premises or a portion thereof, in the proportion that the
rentable area of the portion of the Premises that Tenant is prevented from
using, and does not use, bears to the total rentable area of the Premises;
provided, however, in the event that Tenant is prevented from using, and does
not use, a portion of the Premises for a period of time in excess of the
Eligibility Period and the remaining portion of the Premises is not sufficient
to allow Tenant to effectively conduct its business therein, and if Tenant does
not conduct its business from such remaining portion, then for such time after
expiration of the Eligibility Period during which Tenant is so prevented from
effectively conducting its business therein, the Base Rent and Tenant's Share of
Building Direct Expenses for the entire Premises shall be abated for such time
as Tenant continues to be so prevented from using, and does not use, the
Premises.  If, however, Tenant reoccupies any portion of the Premises during
such period, the rent allocable to such reoccupied portion, based on the

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proportion that the rentable area of such reoccupied portion of the Premises
bears to the total rentable area of the Premises, shall be payable by Tenant
from the date Tenant reoccupies such portion of the Premises.  Such right to
abate Base Rent and Tenant's Share of Building Direct Expenses shall be Tenant's
sole and exclusive remedy at law or in equity for an Abatement Event.  Except as
provided in this Section 19.5, nothing contained herein shall be interpreted to
mean that Tenant is excused from paying Rent due hereunder.

     19.6  LANDLORD DEFAULT.  Notwithstanding anything to the contrary set forth
in this Lease, Landlord shall not be in default  in the performance of any
obligation required to be performed by Landlord pursuant to this Lease unless
(i) in the event such default is with respect to the payment of money, Landlord
fails to pay such unpaid amounts within five (5) business days of written notice
from Tenant that the same was not paid when due, or (ii) in the event such
default is other than the obligation to pay money, Landlord fails to perform
such obligation within thirty (30) days after the receipt of notice from Tenant
specifying in detail Landlord's failure to perform; provided, however, if the
nature of Landlord's obligation is such that more than thirty (30) days are
required for its performance, then Landlord shall not be in default under this
Lease if it shall commence such performance within such thirty (30) day period
and thereafter diligently pursue the same to completion.  Upon any such default
by Landlord under this Lease, Tenant may, except as otherwise specifically
waived in this Lease, exercise any of its rights provided at law or in equity.

                                   ARTICLE 20
                                   ----------

                          COVENANT OF QUIET ENJOYMENT
                          ---------------------------

     Landlord covenants that Tenant, on paying the Rent, charges for services
and other payments herein reserved and on keeping, observing and performing all
the other terms, covenants, conditions, provisions and agreements herein
contained on the part of Tenant to be kept, observed and performed, shall,
during the Lease Term, peaceably and quietly have, hold and enjoy the Premises
subject to the terms, covenants, conditions, provisions and agreements hereof
without interference by any persons lawfully claiming by or through Landlord.
The foregoing covenant is in lieu of any other covenant express or implied.

                                   ARTICLE 21
                                   ----------

                                SECURITY DEPOSIT
                                ----------------

     21.1  SECURITY DEPOSIT.  Concurrent with Tenant's execution of this Lease,
Tenant shall deposit with Landlord a security deposit (the "SECURITY DEPOSIT")
in the amount set forth in Section 7 of the Summary, as security for the
faithful performance by Tenant of all of its obligations under this Lease.  If
Tenant defaults with respect to any provisions of this Lease, including, but not
limited to, the provisions relating to the payment of Rent, the removal of
property and the repair of resultant damage, Landlord may, without notice to
Tenant, but shall not be required to, apply all or any part of the Security
Deposit for the payment of any Rent or any other sum in default and Tenant
shall, upon demand therefor, restore the Security Deposit to

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its original amount. Any unapplied portion of the Security Deposit shall be
returned to Tenant, or, at Landlord's option, to the last assignee of Tenant's
interest hereunder, within sixty (60) days following the expiration of the Lease
Term. Tenant shall not be entitled to any interest on the Security Deposit.
Tenant hereby waives the provisions of Section 1950.7 of the California Civil
Code, or any successor statute.

     21.2  LETTER OF CREDIT.  In lieu of depositing with Landlord the Security
Deposit, as provided for in Section 21.1 above, Tenant shall have the option, to
deliver to Landlord concurrent with Tenant's execution of this Lease, an
unconditional, clean, irrevocable letter of credit (the "L-C") in the amount of
$54,450.00, which L-C shall be issued by a money-center bank (a bank which
accepts deposits, maintains accounts, has a local Los Angeles office which will
negotiate a letter of credit, and whose deposits are insured by the FDIC)
reasonably acceptable to Landlord, and which L-C shall be in a form and content
reasonably acceptable to Landlord.  Tenant shall pay all expenses, points and/or
fees incurred by Tenant in obtaining the L-C.

          21.2.1  APPLICATION OF THE L-C.  The L-C shall be held by Landlord as
security for the faithful performance by Tenant of all the terms, covenants, and
conditions of this Lease to be kept and performed by Tenant during the Lease
Term.  The L-C shall not be mortgaged, assigned or encumbered in any manner
whatsoever by Tenant without the prior written consent of Landlord.  If Tenant
defaults with respect to any provisions of this Lease, including, but not
limited to, the provisions relating to the payment of Rent, or if Tenant fails
to renew the L-C at least thirty (30) days before its expiration, Landlord may,
but shall not be required to, draw upon all or any portion of the L-C for the
payment of any Rent or any other sum in default, or for the payment of any
amount that Landlord may reasonably spend or may become obligated to spend by
reason of Tenant's default, or to compensate Landlord for any other loss or
damage that Landlord may suffer by reason of Tenant's default.  The use,
application or retention of the L-C, or any portion thereof, by Landlord shall
not prevent Landlord from exercising any other right or remedy provided by this
Lease or by law, it being intended that Landlord shall not first be required to
proceed against the L-C and shall not operate as a limitation on any recovery to
which Landlord may otherwise be entitled.  Any amount of the L-C which is drawn
upon by Landlord, but is not used or applied by Landlord, shall be returned to
the bank by Landlord, unless drawn as a result of Tenant's failure to renew the
L-C at least thirty (30) days prior to its expiration, in which case such
amounts shall be returned to Tenant upon Tenant's provision to Landlord of a new
L-C.  If any portion of the L-C is drawn upon, Tenant shall, within five (5)
days after written demand therefor, reinstate the L-C to the amount then
required under this Lease, , and Tenant's failure to do so shall be a default
under this Lease.  Tenant acknowledges that Landlord has the right to transfer
or mortgage its interest in the Real Property and the Building and in this Lease
and Tenant agrees that in the event of any such transfer or mortgage, Landlord
shall have the right to transfer or assign the L-C to the transferee or
mortgagee, and in the event of such transfer, Tenant shall look solely to such
transferee or mortgagee for the return of the L-C.  If Tenant shall fully and
faithfully perform every provision of this Lease to be performed by it, the L-C,
or any balance thereof, shall be returned to Tenant within thirty (30) days
following the expiration of the Lease Term.

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                                   ARTICLE 22
                                   ----------

                             INTENTIONALLY OMITTED
                             ---------------------

                                   ARTICLE 23
                                   ----------

                                     SIGNS
                                     -----

     23.1  EXTERIOR SIGNAGE.  Subject to Landlord's prior written approval, in
its sole discretion, and provided that any sign is in keeping with the quality,
design and style of the Building and Project and is in compliance with all
covenants, conditions or restrictions affecting the Project, and all applicable
law, Tenant, at its sole cost and expense, shall have the exclusive right to
install identification signage on the Building in accordance with the Project
standard signage program.

     23.2  PROHIBITED SIGNAGE AND OTHER ITEMS.  Any signs, notices, logos,
pictures, names or advertisements which are installed and that have not been
separately approved by Landlord may be removed without notice by Landlord at the
sole expense of Tenant.  Except as is set forth in Section 23.1, above, Tenant
may not install any signs on the exterior or roof of the Building or the Common
Areas.  Any signs, window coverings, or blinds (even if the same are located
behind the Landlord-approved window coverings for the Building), or other items
visible from the exterior of the Premises or Building, shall be subject to the
prior approval of Landlord, in its sole discretion.

                                   ARTICLE 24
                                   ----------

                              COMPLIANCE WITH LAW
                              -------------------

     Tenant shall not do anything or suffer anything to be done in or about the
Premises or the Project which will in any way conflict with any law, statute,
ordinance or other governmental rule, regulation or requirement now in force or
which may hereafter be enacted or promulgated.  At its sole cost and expense,
Tenant shall promptly comply with all such governmental measures relating to the
Premises and Building, other than the making of changes to the Base Building.
Should any standard or regulation now or hereafter be imposed on Landlord or
Tenant by a state, federal or local governmental body charged with the
establishment, regulation and enforcement of occupational, health or safety
standards for employers, employees, landlords or tenants, then Tenant agrees, at
its sole cost and expense, to comply promptly with such standards or
regulations.  The judgment of any court of competent jurisdiction or the
admission of Tenant in any judicial action, regardless of whether Landlord is a
party thereto, that Tenant has violated any of said governmental measures, shall
be conclusive of that fact as between Landlord and Tenant.

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                                   ARTICLE 25
                                   ----------

                                  LATE CHARGES
                                  ------------

     If any installment of Rent or any other sum due from Tenant shall not be
received by Landlord or Landlord's designee within five (5) days after said
amount is due, then Tenant shall pay to Landlord a late charge equal to five
percent (5%) of the overdue amount plus any attorneys' fees incurred by Landlord
by reason of Tenant's failure to pay Rent and/or other charges when due
hereunder.  The late charge shall be deemed Additional Rent and the right to
require it shall be in addition to all of Landlord's other rights and remedies
hereunder or at law and shall not be construed as liquidated damages or as
limiting Landlord's remedies in any manner.  In addition to the late charge
described above, any Rent or other amounts owing hereunder which are not paid
within ten (10) days after the date they are due shall bear interest from the
date when due until paid at a rate per annum equal to the lesser of (i) the
annual "Bank Prime Loan" rate cited in the Federal Reserve Statistical Release
Publication G.13(415), published on the first Tuesday of each calendar month (or
such other comparable index as Landlord and Tenant shall reasonably agree upon
if such rate ceases to be published) plus four (4) percentage points, and (ii)
the highest rate permitted by applicable law.


                                   ARTICLE 26
                                   ----------

              LANDLORD'S RIGHT TO CURE DEFAULT; PAYMENTS BY TENANT
              ----------------------------------------------------

     26.1  LANDLORD'S CURE.  All covenants and agreements to be kept or
performed by Tenant under this Lease shall be performed by Tenant at Tenant's
sole cost and expense and without any reduction of Rent, except to the extent,
if any, otherwise expressly provided herein.  If Tenant shall fail to perform
any obligation under this Lease, and such failure shall continue in excess of
the time allowed under Section 19.1.2, above, unless a specific time period is
otherwise stated in this Lease, Landlord may, but shall not be obligated to,
make any such payment or perform any such act on Tenant's part without waiving
its rights based upon any default of Tenant and without releasing Tenant from
any obligations hereunder.

     26.2  TENANT'S REIMBURSEMENT.  Except as may be specifically provided to
the contrary in this Lease, Tenant shall pay to Landlord, upon delivery by
Landlord to Tenant of statements therefor:  (i) sums equal to expenditures
reasonably made and obligations incurred by Landlord in connection with the
remedying by Landlord of Tenant's defaults pursuant to the provisions of Section
26.1; (ii) sums equal to all losses, costs, liabilities, damages and expenses
referred to in Article 10 of this Lease; and (iii) sums equal to all
expenditures made and obligations incurred by Landlord in collecting or
attempting to collect the Rent or in enforcing or attempting to enforce any
rights of Landlord under this Lease or pursuant to law, including, without
limitation, all legal fees and other amounts so expended.  Tenant's obligations
under this Section 26.2 shall survive the expiration or sooner termination of
the Lease Term.

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                                   ARTICLE 27
                                   ----------

                               ENTRY BY LANDLORD
                               -----------------

     Landlord reserves the right at all reasonable times and upon reasonable
notice to Tenant (except in the case of an emergency) to enter the Premises to
(i) inspect them; (ii) show the Premises to prospective purchasers, mortgagees
or tenants, or to current or prospective mortgagees, ground or underlying
lessors or insurers; (iii) post notices of nonresponsibility; or (iv) alter,
improve or repair the Premises or the Building, or for structural alterations,
repairs or improvements to the Building or the Building's systems and equipment.
Notwithstanding anything to the contrary contained in this Article 27, Landlord
may enter the Premises at any time to (A) perform services required of Landlord,
including janitorial service; (B) take possession due to any breach of this
Lease in the manner provided herein; and (C) perform any covenants of Tenant
which Tenant fails to perform.  Landlord may make any such entries without the
abatement of Rent and may take such reasonable steps as required to accomplish
the stated purposes.  Tenant hereby waives any claims for damages or for any
injuries or inconvenience to or interference with Tenant's business, lost
profits, any loss of occupancy or quiet enjoyment of the Premises, and any other
loss occasioned thereby.  For each of the above purposes, Landlord shall at all
times have a key with which to unlock all the doors in the Premises, excluding
Tenant's vaults, safes and special security areas designated in advance by
Tenant.  In an emergency, Landlord shall have the right to use any means that
Landlord may deem proper to open the doors in and to the Premises.  Any entry
into the Premises by Landlord in the manner hereinbefore described shall not be
deemed to be a forcible or unlawful entry into, or a detainer of, the Premises,
or an actual or constructive eviction of Tenant from any portion of the
Premises.  No provision of this Lease shall be construed as obligating Landlord
to perform any repairs, alterations or decorations except as otherwise expressly
agreed to be performed by Landlord herein.

                                   ARTICLE 28
                                   ----------

                                 TENANT PARKING
                                 --------------

     Tenant shall have the right, during the Lease Term, to use up to the number
of parking spaces in the Project parking areas as set forth in Section 9 of the
Summary.  Such use shall be free of charge during the initial Lease Term.
Landlord agrees that, out of the space available to Tenant, ten (10) spaces
located adjacent to the Building shall be reserved for Tenant's exclusive use.
Tenant's continued right to use the parking areas is conditioned upon Tenant
abiding by all rules and regulations which are prescribed from time to time for
the orderly operation and use of such areas, including any sticker or other
identification system established by Landlord, Tenant's cooperation in seeing
that Tenant's employees and visitors also comply with such rules and regulations
and Tenant not being in default under this Lease.  Landlord specifically
reserves the right to change the size, configuration, design, layout and all
other aspects of the Project parking areas at any time (without reducing the
number of parking spaces for use by Tenant) and Tenant acknowledges and agrees
that Landlord may, without incurring any liability to Tenant and without any
abatement of Rent under this Lease, from time to time, close-off or restrict
access to

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the Project areas facility for purposes of permitting or facilitating any such
construction, alteration or improvements. Landlord may delegate its
responsibilities hereunder to a parking operator in which case such parking
operator shall have all the rights of control attributed hereby to the Landlord.

                                   ARTICLE 29
                                   ----------

                            MISCELLANEOUS PROVISIONS
                            ------------------------

     29.1  TERMS; CAPTIONS.  The words "Landlord" and "Tenant" as used herein
shall include the plural as well as the singular.  The necessary grammatical
changes required to make the provisions hereof apply either to corporations or
partnerships or individuals, men or women, as the case may require, shall in all
cases be assumed as though in each case fully expressed.  The captions of
Articles and Sections are for convenience only and shall not be deemed to limit,
construe, affect or alter the meaning of such Articles and Sections.

     29.2  BINDING EFFECT.  Subject to all other provisions of this Lease, each
of the covenants, conditions and provisions of this Lease shall extend to and
shall, as the case may require, bind or inure to the benefit not only of
Landlord and of Tenant, but also of their respective heirs, personal
representatives, successors or assigns, provided this clause shall not permit
any assignment by Tenant contrary to the provisions of Article 14 of this Lease.

     29.3  NO AIR RIGHTS.  No rights to any view or to light or air over any
property, whether belonging to Landlord or any other person, are granted to
Tenant by this Lease.  If at any time any windows of the Premises are
temporarily darkened or the light or view therefrom is obstructed by reason of
any repairs, improvements, maintenance or cleaning in or about the  Project, the
same shall be without liability to Landlord and without any reduction or
diminution of Tenant's obligations under this Lease.

     29.4  MODIFICATION OF LEASE.  Should any current or prospective mortgagee
or ground lessor for the Building or Project require a modification of this
Lease, which modification will not cause an increased cost or expense to Tenant
or in any other way materially and adversely change the rights and obligations
of Tenant hereunder, then and in such event, Tenant agrees that this Lease may
be so modified and agrees to execute whatever documents are reasonably required
therefor and to deliver the same to Landlord within ten (10) days following a
request therefor.  At the request of Landlord or any mortgagee or ground lessor,
Tenant agrees to execute a short form of Lease and deliver the same to Landlord
within ten (10) days following the request therefor.

     29.5  TRANSFER OF LANDLORD'S INTEREST.  Tenant acknowledges that Landlord
has the right to transfer all or any portion of its interest in the Project or
Building and in this Lease, and Tenant agrees that in the event of any such
transfer, Landlord shall automatically be released from all liability under this
Lease and Tenant agrees to look solely to such transferee for the performance of
Landlord's obligations hereunder after the date of transfer and such transferee
shall be deemed to have fully assumed and be liable for all obligations of this
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performed by Landlord, including the return of any Security Deposit, and Tenant
shall attorn to such transferee.

     29.6  PROHIBITION AGAINST RECORDING.  Except as provided in Section 29.4 of
this Lease, neither this Lease, nor any memorandum, affidavit or other writing
with respect thereto, shall be recorded by Tenant or by anyone acting through,
under or on behalf of Tenant.

     29.7  LANDLORD'S TITLE.  Landlord's title is and always shall be paramount
to the title of Tenant.  Nothing herein contained shall empower Tenant to do any
act which can, shall or may encumber the title of Landlord (except in connection
with mechanics' or materialmen's liens in connection with Tenant construction in
the Building pursuant to the terms of this Lease).

     29.8  RELATIONSHIP OF PARTIES.  Nothing contained in this Lease shall be
deemed or construed by the parties hereto or by any third party to create the
relationship of principal and agent, partnership, joint venturer or any
association between Landlord and Tenant.

     29.9  APPLICATION OF PAYMENTS.  Landlord shall have the right to apply
payments received from Tenant pursuant to this Lease, regardless of Tenant's
designation of such payments, to satisfy any obligations of Tenant hereunder, in
such order and amounts as Landlord, in its sole discretion, may elect.

     29.10  TIME OF ESSENCE.  Time is of the essence with respect to the
performance of every provision of this Lease in which time of performance is a
factor.

     29.11  PARTIAL INVALIDITY.  If any term, provision or condition contained
in this Lease shall, to any extent, be invalid or unenforceable, the remainder
of this Lease, or the application of such term, provision or condition to
persons or circumstances other than those with respect to which it is invalid or
unenforceable, shall not be affected thereby, and each and every other term,
provision and condition of this Lease shall be valid and enforceable to the
fullest extent possible permitted by law.

     29.12  NO WARRANTY.  In executing and delivering this Lease, Tenant has not
relied on any representations, including, but not limited to, any representation
as to the amount of any item comprising Additional Rent or the amount of the
Additional Rent in the aggregate or that Landlord is furnishing the same
services to other tenants, at all, on the same level or on the same basis, or
any warranty or any statement of Landlord which is not set forth herein or in
one or more of the exhibits attached hereto.

     29.13  LANDLORD EXCULPATION.  The liability of Landlord or the Landlord
Parties to Tenant for any default by Landlord under this Lease or arising in
connection herewith or with Landlord's operation, management, leasing, repair,
renovation, alteration or any other matter relating to the Project or the
Premises shall be limited solely and exclusively to an amount which is equal to
the interest of Landlord in the Project, provided that in no event shall such
liability extend to any sales or insurance proceeds received by Landlord or the
Landlord Parties in connection with the Project, Building or Premises.  The
parties agree that the terms of this

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Section 29.13 are not intended and shall not relieve any insurance carrier of
its obligations under any insurance policies carried by Landlord or Tenant in
connection with the Project, the Building or the Premises. Neither Landlord, nor
any of the Landlord Parties shall have any personal liability therefor, and
Tenant hereby expressly waives and releases such personal liability on behalf of
itself and all persons claiming by, through or under Tenant. The limitations of
liability contained in this Section 29.13 shall inure to the benefit of
Landlord's and the Landlord Parties' present and future partners, beneficiaries,
officers, directors, trustees, shareholders, agents and employees, and their
respective partners, heirs, successors and assigns. Under no circumstances shall
any present or future partner of Landlord (if Landlord is a partnership), or
trustee or beneficiary (if Landlord or any partner of Landlord is a trust), have
any liability for the performance of Landlord's obligations under this Lease.
Notwithstanding any contrary provision herein, neither Landlord nor the Landlord
Parties shall be liable under any circumstances for injury or damage to, or
interference with, Tenant's business, including but not limited to, loss of
profits, loss of rents or other revenues, loss of business opportunity, loss of
goodwill or loss of use, in each case, however occurring.

     29.14  ENTIRE AGREEMENT.  It is understood and acknowledged that there are
no oral agreements between the parties hereto affecting this Lease and this
Lease constitutes the parties' entire agreement with respect to the leasing of
the Premises and supersedes and cancels any and all previous negotiations,
arrangements, brochures, agreements and understandings, if any, between the
parties hereto or displayed by Landlord to Tenant with respect to the subject
matter thereof, and none thereof shall be used to interpret or construe this
Lease.  None of the terms, covenants, conditions or provisions of this Lease can
be modified, deleted or added to except in writing signed by the parties hereto.

     29.15  RIGHT TO LEASE.  Landlord reserves the absolute right to effect such
other tenancies in the Project as Landlord in the exercise of its sole business
judgment shall determine to best promote the interests of the Building or
Project.  Tenant does not rely on the fact, nor does Landlord represent, that
any specific tenant or type or number of tenants shall, during the Lease Term,
occupy any space in the Building or Project.

     29.16  FORCE MAJEURE.  Any prevention, delay or stoppage due to strikes,
lockouts, labor disputes, acts of God, inability to obtain services, labor, or
materials or reasonable substitutes therefor, governmental actions, civil
commotions, fire or other casualty, and other causes beyond the reasonable
control of the party obligated to perform, except with respect to the
obligations imposed with regard to Rent and other charges to be paid by Tenant
pursuant to this Lease (collectively, a "FORCE MAJEURE"), notwithstanding
anything to the contrary contained in this Lease, shall excuse the performance
of such party for a period equal to any such prevention, delay or stoppage and,
therefore, if this Lease specifies a time period for performance of an
obligation of either party, that time period shall be extended by the period of
any delay in such party's performance caused by a Force Majeure.

     29.17  WAIVER OF REDEMPTION BY TENANT.  Tenant hereby waives, for Tenant
and for all those claiming under Tenant, any and all rights now or hereafter
existing to redeem by order or

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judgment of any court or by any legal process or writ, Tenant's right of
occupancy of the Premises after any termination of this Lease.

     29.18  NOTICES.  All notices, demands, statements, designations, approvals
or other communications (collectively, "NOTICES") given or required to be given
by either party to the other hereunder or by law shall be in writing, shall be
(A) sent by United States certified or registered mail, postage prepaid, return
receipt requested ("MAIL"), (B) transmitted by telecopy, if such telecopy is
promptly followed by a Notice sent by Mail, (C) delivered by a nationally
recognized overnight courier, or (D) delivered personally.  Any Notice shall be
sent, transmitted, or delivered, as the case may be, to Tenant at the
appropriate address set forth in Section 10 of the Summary, or to such other
place as Tenant may from time to time designate in a Notice to Landlord, or to
Landlord at the addresses set forth in Section 11 of the Summary, or to such
other places as Landlord may from time to time designate in a Notice to Tenant.
Any Notice will be deemed given (i) three (3) days after the date it is posted
if sent by Mail, (ii) the date the telecopy is transmitted, (iii) the date the
overnight courier delivery is made, or (iv) the date personal delivery is made

     29.19  JOINT AND SEVERAL.  If there is more than one Tenant, the
obligations imposed upon Tenant under this Lease shall be joint and several.

     29.20  AUTHORITY.  If Tenant is a corporation, trust or partnership, each
individual executing this Lease on behalf of Tenant hereby represents and
warrants that Tenant is a duly formed and existing entity qualified to do
business in California and that Tenant has full right and authority to execute
and deliver this Lease and that each person signing on behalf of Tenant is
authorized to do so.  In such event, Tenant shall, within ten (10) days after
execution of this Lease, deliver to Landlord satisfactory evidence of such
authority and, if a corporation, upon demand by Landlord, also deliver to
Landlord satisfactory evidence of (i) good standing in Tenant's state of
incorporation and (ii) qualification to do business in California.

     29.21  ATTORNEYS' FEES.  In the event that either Landlord or Tenant should
bring suit for the possession of the Premises, for the recovery of any sum due
under this Lease, or because of the breach of any provision of this Lease or for
any other relief against the other, then all costs and expenses, including
reasonable attorneys' fees, incurred by the prevailing party therein shall be
paid by the other party, which obligation on the part of the other party shall
be deemed to have accrued on the date of the commencement of such action.

     29.22  GOVERNING LAW; WAIVER OF TRIAL BY JURY.  This Lease shall be
construed and enforced in accordance with the laws of the State of California.
IN ANY ACTION OR PROCEEDING ARISING HEREFROM, LANDLORD AND TENANT HEREBY CONSENT
TO (I) THE JURISDICTION OF ANY COMPETENT COURT WITHIN THE STATE OF CALIFORNIA,
(II) SERVICE OF PROCESS BY ANY MEANS AUTHORIZED BY CALIFORNIA LAW, AND (III) IN
THE INTEREST OF SAVING TIME AND EXPENSE, TRIAL WITHOUT A JURY IN ANY ACTION,
PROCEEDING OR COUNTERCLAIM BROUGHT BY EITHER OF THE PARTIES HERETO AGAINST THE
OTHER OR THEIR SUCCESSORS IN RESPECT OF ANY MATTER ARISING OUT OF OR IN
CONNECTION

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WITH THIS LEASE, THE RELATIONSHIP OF LANDLORD AND TENANT, TENANT'S USE OR
OCCUPANCY OF THE PREMISES, AND/OR ANY CLAIM FOR INJURY OR DAMAGE, OR ANY
EMERGENCY OR STATUTORY REMEDY.

     29.23  SUBMISSION OF LEASE.  Submission of this instrument for examination
or signature by Tenant does not constitute a reservation of, option for or
option to lease, and it is not effective as a lease or otherwise until execution
and delivery by both Landlord and Tenant.

     29.24  BROKERS.  Landlord and Tenant hereby warrant to each other that they
have had no dealings with any real estate broker or agent in connection with the
negotiation of this Lease, excepting only the real estate brokers or agents
specified in Section 12 of the Summary (the "BROKERS"), and that they know of no
other real estate broker or agent who is entitled to a commission in connection
with this Lease.  Each party agrees to indemnify and defend the other party
against and hold the other party harmless from any and all claims, demands,
losses, liabilities, lawsuits, judgments, costs and expenses (including without
limitation reasonable attorneys' fees) with respect to any leasing commission or
equivalent compensation alleged to be owing on account of any dealings with any
real estate broker or agent, other than the Brokers, occurring by, through, or
under the indemnifying party.

     29.25  INDEPENDENT COVENANTS.  This Lease shall be construed as though the
covenants herein between Landlord and Tenant are independent and not dependent
and Tenant hereby expressly waives the benefit of any statute to the contrary
and agrees that if Landlord fails to perform its obligations set forth herein,
Tenant shall not be entitled to make any repairs or perform any acts hereunder
at Landlord's expense or to any setoff of the Rent or other amounts owing
hereunder against Landlord.

     29.26  PROJECT OR BUILDING NAME AND SIGNAGE.  Landlord shall have the right
at any time to change the name of the Project or Building and to install, affix
and maintain any and all signs on the exterior and on the interior of the
Project or, except with respect to other tenant signage, Building as Landlord
may, in Landlord's sole discretion, desire.  Tenant shall not use the words
"Irvine Oaks" or the name of the Project or Building or use pictures or
illustrations of the Project or Building in advertising or other publicity or
for any purpose other than as the address of the business to be conducted by
Tenant in the Premises, without the prior written consent of Landlord.

     29.27  COUNTERPARTS.  This Lease may be executed in counterparts with the
same effect as if both parties hereto had executed the same document.  Both
counterparts shall be construed together and shall constitute a single lease.

     29.28  CONFIDENTIALITY.  The parties acknowledge that the content of this
Lease and any related documents are confidential information.  The parties shall
keep such confidential information strictly confidential and shall not disclose
such confidential information to any person or entity as reasonably necessary.

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     29.29  DEVELOPMENT OF THE PROJECT.

          29.29.1  SUBDIVISION.  Landlord reserves the right to further
subdivide all or a portion of the Project.  Tenant agrees to execute and
deliver, upon demand by Landlord and in the form requested by Landlord, any
additional documents needed to conform this Lease to the circumstances resulting
from such subdivision.

          29.29.2  THE OTHER IMPROVEMENTS.  If portions of the Project or
property adjacent to the Project (collectively, the "OTHER IMPROVEMENTS") are
owned by an entity other than Landlord, Landlord, at its option, may enter into
an agreement with the owner or owners of any or all of the Other Improvements to
provide (i) for reciprocal rights of access and/or use of the Project and the
Other Improvements, (ii) for the common management, operation, maintenance,
improvement and/or repair of all or any portion of the Project and the Other
Improvements, (iii) for the allocation of a portion of the Direct Expenses to
the Other Improvements and the operating expenses and taxes for the Other
Improvements to the Project, and (iv) for the use or improvement of the Other
Improvements and/or the Project in connection with the improvement,
construction, and/or excavation of the Other Improvements and/or the Project.
Nothing contained herein shall be deemed or construed to limit or otherwise
affect Landlord's right to convey all or any portion of the Project or any other
of Landlord's rights described in this Lease.

          29.29.3  CONSTRUCTION OF PROJECT AND OTHER IMPROVEMENTS.  Tenant
acknowledges that portions of the Project and/or the Other Improvements may be
under construction following Tenant's occupancy of the Premises, and that such
construction may result in levels of noise, dust, obstruction of access, etc.
which are in excess of that present in a fully constructed project.  Provided
that Landlord shall not materially obstruct Tenant's access to the Premises, and
except as otherwise expressly provided herein, Tenant hereby waives any and all
rent offsets or claims of constructive eviction which may arise in connection
with such construction.

     29.30  BUILDING RENOVATIONS.  It is specifically understood and agreed that
Landlord has no obligation and has made no promises to alter, remodel, improve,
renovate, repair or decorate the Premises, Building, or any part thereof and
that no representations respecting the condition of the Premises or the Building
have been made by Landlord to Tenant except as specifically set forth herein or
in the Tenant Work Letter.  However, Tenant hereby acknowledges that Landlord is
currently renovating or may during the Lease Term renovate, improve, alter, or
modify (collectively, the "RENOVATIONS") the Project, the Building and/or the
Premises.  Tenant hereby agrees that such Renovations shall in no way constitute
a constructive eviction of Tenant nor entitle Tenant to any abatement of Rent.
Landlord shall have no responsibility and shall not be liable to Tenant for any
injury to or interference with Tenant's business arising from the Renovations,
nor shall Tenant be entitled to any compensation or damages from Landlord for
loss of the use of the whole or any part of the Premises or of Tenant's personal
property or improvements resulting from the Renovations, or for any
inconvenience or annoyance occasioned by such Renovations.

                                      -49-

                                                      IRVINE OAKS EXECUTIVE PARK
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<PAGE>

     29.31  NO VIOLATION.  Tenant hereby warrants and represents that neither
its execution of nor performance under this Lease shall cause Tenant to be in
violation of any agreement, instrument, contract, law, rule or regulation by
which Tenant is bound, and Tenant shall protect, defend, indemnify and hold
Landlord harmless against any claims, demands, losses, damages, liabilities,
costs and expenses, including, without limitation, reasonable attorneys' fees
and costs, arising from Tenant's breach of this warranty and representation.

     29.32  Arbitration.

          29.32.1  Submittals to Arbitration.  The submittal of all matters to
arbitration in accordance with the terms of this Section 29.32 is the sole and
exclusive method, means and procedure to resolve any and all claims, disputes or
disagreements arising under Section 7.2 of this Lease.  The parties hereby
irrevocably waive any and all rights to the contrary and shall at all times
conduct themselves in strict, full, complete and timely accordance with the
terms of this Section 29.32.  As to any matter submitted to arbitration with
respect to the payment of money, to determine whether a matter would, with the
passage of time, constitute a default, such passage of time shall not commence
to run in the event that the party which is obligated to make the payment does
in fact make the payment to the other party.  Such payment can be made "under
protest," which shall occur when such payment is accompanied by a good faith
notice stating the reasons that the party has elected to make a payment under
protest.  Such protest will be deemed waived unless the subject matter
identified in the protest is submitted to arbitration as set forth in this
Section 29.32.

          29.32.2  JAMS.  Any dispute to be arbitrated pursuant to the
provisions of this Section 29.32 shall be determined by binding arbitration
before a retired judge of the Superior Court of the State of California (the
"Arbitrator") under the auspices of Judicial Arbitration & Mediation Services,
Inc. ("JAMS").  Such arbitration shall be initiated by the parties, or either of
them, within ten (10) days after either party sends written notice (the
"Arbitration Notice") of a demand to arbitrate by registered or certified mail
to the other party and to JAMS.  The Arbitration Notice shall contain a
description of the subject matter of the arbitration, the dispute with respect
thereto, the amount involved, if any, and the remedy or determination sought.
The parties may agree on a retired  judge from the JAMS panel.  If they are
unable to promptly agree, JAMS will provide a list of three available judges and
each party may strike one.  The remaining judge (or if there are two, the one
selected by JAMS) will serve as the Arbitrator.  In the event that JAMS shall no
longer exist or if JAMS fails or refuses to accept submission of such dispute,
then the dispute shall be resolved by binding arbitration before the American
Arbitration Association ("AAA") under the AAA's commercial arbitration rules
then in effect.

          29.32.3  Arbitration Procedure.

               29.32.3.1  Pre-Decision Actions. The Arbitrator shall schedule a
pre-hearing conference to resolve procedural matters, arrange for the exchange
of information, obtain stipulations, and narrow the issues. The parties will
submit proposed discovery schedules to the Arbitrator at the pre-hearing
conference. The scope and duration of discovery will be within the sole
discretion of the Arbitrator. The Arbitrator shall have the discretion to order
a pre-hearing

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<PAGE>

exchange of information by the parties, including, without limitation,
production of requested documents, exchange of summaries of testimony of
proposed witnesses, and examination by deposition of parties and third-party
witnesses. This discretion shall be exercised in favor of discovery reasonable
under the circumstances.

          29.32.3.2  The Decision.  The arbitration shall be conducted in Orange
County, California.  Any party may be represented by counsel or other authorized
representative.  In rendering a decision(s), the Arbitrator shall determine the
rights and obligations of the parties according to the substantive and
procedural laws of the State of California and the terms and provisions of this
Lease.  The Arbitrator's decision shall be based on the evidence introduced at
the hearing, including all logical and reasonable inferences therefrom.  The
Arbitrator may make any determination, and/or grant any remedy or relief that is
just and equitable.  The decision must be based on, and accompanied by, a
written statement of decision explaining the factual and legal basis for the
decision as to each of the principal controverted issues.  The decision shall be
conclusive and binding, and it may thereafter be confirmed as a judgment by the
Superior Court of the State of California, subject only to challenge on the
grounds set forth in the California Code of Civil Procedure Section 1286.2.  The
validity and enforceability of the Arbitrator's decision is to be determined
exclusively by the California courts pursuant to the provisions of this Lease.
The Arbitrator may award costs, including without limitation attorneys' fees,
and expert and witness costs, to the prevailing party, if any, as determined by
the Arbitrator in his discretion.  The Arbitrator's fees and costs shall be paid
by the non-prevailing party as determined by the Arbitrator in his discretion.
A party shall be determined by the Arbitrator to be the prevailing party if its
proposal for the resolution of dispute is the closer to that adopted by the
Arbitrator.

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                                                      IRVINE OAKS EXECUTIVE PARK
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<PAGE>

     IN WITNESS WHEREOF, Landlord and Tenant have caused this Lease to be
executed the day and date first above written.


                                  "LANDLORD":

                                  MAGELLAN IRVINE OAKS LIMITED PARTNERSHIP,
                                  an Arizona limited partnership

                                  By: _____________________________________

                                     Its:__________________________________


                                  "TENANT":

                                  MICROSIM CORPORATION,
                                  a California corporation

                                  By: _____________________________________

                                     Its:_____________________________________


                                  By: _____________________________________

                                     Its:_____________________________________

                                      -52-

                                                      IRVINE OAKS EXECUTIVE PARK
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<PAGE>

                                   EXHIBIT A
                                   ---------

                           IRVINE OAKS EXECUTIVE PARK
                           --------------------------

                              OUTLINE OF PREMISES
                              -------------------



                              EXHIBIT A - Page 1

                                                      IRVINE OAKS EXECUTIVE PARK
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<PAGE>

                                  Blank Page

                              EXHIBIT A - Page 2

                                                      IRVINE OAKS EXECUTIVE PARK
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<PAGE>

                                   EXHIBIT B
                                   ---------

                           IRVINE OAKS EXECUTIVE PARK
                           --------------------------

                               TENANT WORK LETTER
                               ------------------

     This Tenant Work Letter shall set forth the terms and conditions relating
to the construction of the tenant improvements in the Premises.  This Tenant
Work Letter is essentially organized chronologically and addresses the issues of
the construction of the Premises, in sequence, as such issues will arise during
the actual construction of the Premises.  All references in this Tenant Work
Letter to Articles or Sections of "this Lease" shall mean the relevant portion
of Articles 1 through 29 of the Office Lease to which this Tenant Work Letter is
attached as Exhibit B and of which this Tenant Work Letter forms a part, and all
references in this Tenant Work Letter to Sections of "this Tenant Work Letter"
shall mean the relevant portion of Sections 1 through 6 of this Tenant Work
Letter.

                                   SECTION 1
                                   ---------

                LANDLORD'S INITIAL CONSTRUCTION IN THE PREMISES
                -----------------------------------------------

     Landlord shall construct, at its sole cost and expense, the base, shell,
and core (i) of the Premises and (ii) of the Building (collectively, the "Base,
Shell, and Core" or "Base Building") in accordance with the plans and
specifications described on Schedule 2 attached hereto (the "Design Plans"),
provided that Landlord may make changes to the Design Plans as reasonably deemed
necessary or desirable by Landlord, or as required by law.  Landlord agrees
that, as of the date of substantial completion of the Base Building, the same
shall be in material compliance with applicable building codes, including
handicap access and Title 24 (collectively, "Code"), applicable to the Building
as of such date on an unoccupied basis.  Landlord will use commercially
reasonable efforts to complete the various phases of construction in accordance
with the time deadlines set forth in Schedule 1 attached hereto.

                                   SECTION 2
                                   ---------

                              TENANT IMPROVEMENTS
                              -------------------

     2.1  Tenant Improvement Allowance.  Tenant shall be entitled to a one-time
tenant improvement allowance (the "Tenant Improvement Allowance") in the amount
of $25.00 per usable square foot of the Premises for the costs relating to the
initial design and construction of Tenant's improvements which are permanently
affixed to the Premises (the "Tenant Improvements").  In no event shall Landlord
be obligated to make disbursements pursuant to this Tenant Work Letter in a
total amount which exceeds the Tenant Improvement Allowance.  All Tenant
Improvements for which the Tenant Improvement Allowance has been made available
shall be deemed Landlord's property under the terms of the Lease.

                            EXHIBIT B - Page 1

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<PAGE>

     2.2  Disbursement of the Tenant Improvement Allowance.  Concurrently with
the execution of this Lease, Landlord and Tenant are entering into that certain
Agreement Re Letter of Credit (the "LC Agreement") pursuant to which Landlord
has agreed to deposit the Tenant Improvement Allowance into the "Project
Account," as defined in such LC Agreement.  The Tenant Improvement Allowance
shall be disbursed by Landlord in accordance with the terms of the LC Agreement.
Except as otherwise set forth in this Tenant Work Letter, the Tenant Improvement
Allowance shall be disbursed for costs related to the construction of the Tenant
Improvements and for the following items and costs (collectively, the "Tenant
Improvement Allowance Items"):  (i) payment of the fees of the "Tenant's
Architect", "Architect" and the "Engineers," as those terms are defined in
Section 3.1 of this Tenant Work Letter, and payment of the fees incurred by, and
the cost of documents and materials supplied by, Landlord and Landlord's
consultants in connection with the preparation and review of the "Construction
Drawings," as that term is defined in Section 3.1 of this Tenant Work Letter;
(ii) the cost of any changes in the Base, Shell and Core when such changes are
required by the Construction Drawings; (iii) the cost of any changes to the
Construction Drawings or Tenant Improvements required by Code; (iv) the cost of
Tenant's relocation into the Premises, up to a maximum amount equal to $1.00 per
rentable square foot of the Premises; and (v) the "Landlord Supervision Fee", as
that term is defined in Section 4.3.2 of this Tenant Work Letter.

     2.3  Standard Tenant Improvement Package.  Landlord has established
specifications (the "Specifications") for the Building standard components to be
used in the construction of the Tenant Improvements in the Premises
(collectively, the "Standard Improvement Package"), which Specifications are set
forth on Schedule 3 attached hereto.  The quality of Tenant Improvements shall
be equal to or of greater quality than the quality of the Specifications,
provided that Landlord may, at Landlord's option, require the Tenant
Improvements to comply with certain Specifications.  Landlord may make changes
to the Specifications for the Standard Improvement Package from time to time.

                                   SECTION 3
                                   ---------

                             CONSTRUCTION DRAWINGS
                             ---------------------

     3.1  Selection of Architect/Construction Drawings.  Tenant has retained
Tsutsumida and Associates ("Tenant's Architect") to prepare the "Final Space
Plan," as that term is defined in Section 3.2, below.  Landlord shall retain an
architect/space planner selected by Landlord (the "Architect") to prepare the
"Construction Drawings," as that term is defined in this Section 3.1, and
engineering consultants selected by Landlord (the "Engineers") to prepare all
plans and engineering working drawings relating to the structural, mechanical,
electrical, plumbing, HVAC, lifesafety, and sprinkler work of the Tenant
Improvements, based on the Final Space Plan.  The plans and drawings to be
prepared by Architect and the Engineers hereunder shall be known collectively as
the "Construction Drawings."

     3.2  Final Space Plan.  Tenant and the Tenant's Architect have prepared the
final space plan for Tenant Improvements in the Premises (collectively, the
"Final Space Plan"), which Final Space Plan has been approved by Landlord.

                              EXHIBIT B - Page 2

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     3.3  Final Working Drawings.  The Architect and the Engineers shall
complete the architectural and engineering drawings for the Premises, and the
final architectural working drawings in a form which is complete to allow
subcontractors to bid on the work and to obtain all applicable permits
(collectively, the "Final Working Drawings") and shall submit the same to Tenant
for Tenant's reasonable approval, which approval shall be given within fifty-
three (53) business days after Landlord's delivery of the same to Tenant.
Landlord agrees that the Tenant's Architect may be involved in such approval,
and that any costs relating to such involvement may, at Tenant's option, be
deducted from the Tenant Improvement Allowance.

     3.4  Permits.  Landlord shall submit the Final Working Drawing as approved
by Tenant (the "Approved Working Drawings") to the appropriate municipal
authorities for all applicable building permits necessary to allow "Contractor,"
as that term is defined in Section 4.1, below, to commence and fully complete
the construction of the Tenant Improvements (the "Permits").

     3.5  Time Deadlines.  Tenant shall use its best, good faith, efforts and
all due diligence to cooperate with the Architect, the Engineers, and Landlord
to complete all phases of the Construction Drawings and the permitting process
and to receive the permits, and with Contractor for approval of the "Cost
Proposal," as that term is defined in Section 4.2 of this Tenant Work Letter, as
soon as possible after the execution of the Lease, and, in that regard, shall
meet with Landlord on a scheduled basis to be determined by Landlord, to discuss
Tenant's progress in connection with the same.  The applicable dates for
approval of items, plans and drawings as described in this Section 3, Section 4,
below, and in this Tenant Work Letter are set forth and further elaborated upon
in Schedule 1 (the "Time Deadlines"), attached hereto.  Tenant agrees to comply
with the Time Deadlines.  Schedule 1 also contains Landlord's proposed schedule
for the construction of the Building and the Tenant Improvements.

                                   SECTION 4
                                   ---------

                    CONSTRUCTION OF THE TENANT IMPROVEMENTS
                    ---------------------------------------

     4.1  Contractor.  A contractor selected by Landlord ("Contractor") shall
construct the Tenant Improvements.  Landlord agrees that one (1) contractor
designated by Tenant will be considered for selection by Landlord as the
Contractor.

     4.2  Cost Proposal.  After the Approved Working Drawings are signed by
Landlord and Tenant, Landlord shall provide Tenant with a cost proposal in
accordance with the Approved Working Drawings, which cost proposal shall
include, as nearly as possible, the cost of all Tenant Improvement Allowance
Items to be incurred by Tenant in connection with the design and construction of
the Tenant Improvements (the "Cost Proposal").  Tenant shall approve and deliver
the Cost Proposal to Landlord within five (5) business days of the receipt of
the same, and upon receipt of the same by Landlord, Landlord shall be released
by Tenant to purchase the items set forth in the Cost Proposal and to commence
the construction relating to such items.  The date by which Tenant must approve
and deliver the Cost Proposal to Landlord shall be known hereafter as the "Cost
Proposal Delivery Date".

                              EXHIBIT B - Page 3

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     4.3  Construction of Tenant Improvements by Contractor under the
Supervision of Landlord.

          4.3.1  Over-Allowance Amount.  If the Cost Proposal shows costs
greater than the amount of the Tenant Improvement Allowance (after deducting
from the Tenant Improvement Allowance any amounts expended in connection with
the preparation of the Construction Drawings, and the cost of all other Tenant
Improvement Allowance Items incurred prior to the commencement of construction
of the Tenant Improvements) (the "Over-Allowance Amount") then Tenant shall to
pay a percentage of each amount disbursed by Escrow Holder to the Contractor or
otherwise disbursed under this Tenant Work Letter, which percentage shall be
equal to the Over-Allowance Amount divided by the amount of the Final Costs, and
such payment by Tenant ("Over-Allowance Payment") shall be a condition to
Landlord's obligation to pay any amounts of Tenant Improvement Allowance.  In
the event that, after the Cost Proposal Delivery Date, any revisions, changes,
or substitutions shall be made to the Construction Drawings or the Tenant
Improvements by Tenant, any additional costs which arise in connection with such
revisions, changes or substitutions or any other additional costs shall be paid
by Tenant to Landlord immediately upon Landlord's request as an addition to the
Over-Allowance Amount.

          4.3.2  Landlord's Retention of Contractor.  Landlord shall
independently retain Contractor to construct the Tenant Improvements in
accordance with the Approved Working Drawings and the Cost Proposal and Landlord
shall supervise the construction by Contractor, and Tenant shall pay a
construction supervision and management fee (the "Landlord Supervision Fee") to
Landlord in an amount equal to the product of (i) three percent (3%) and (ii) an
amount equal to the Tenant Improvement Allowance plus the Over-Allowance Amount
(as such Over-Allowance Amount may increase pursuant to the terms of this Tenant
Work Letter), but not including reimbursable amounts payable to the Architects
or Engineers.

          4.3.3  Contractor's Warranties and Guaranties.  Landlord hereby
assigns to Tenant all warranties and guaranties by Contractor relating to the
Tenant Improvements and to those portions of the Base Building which Tenant is
required to maintain pursuant to the terms of the Lease, and Tenant hereby
waives all claims against Landlord relating to, or arising out of the
construction of, the Tenant Improvements.

          4.3.4  Tenant's Covenants.  Tenant hereby indemnifies Landlord for any
loss, claims, damages or delays arising from the actions of Tenant's Architect
on the Premises or in the Building.

                                   SECTION 5
                                   ---------

                     COMPLETION OF THE TENANT IMPROVEMENTS;
                     --------------------------------------
                            LEASE COMMENCEMENT DATE
                            -----------------------

     5.1  Ready for Occupancy.  Subject to the terms of Section 6.1, below, the
Premises shall be deemed "Ready for Occupancy" upon the Substantial Completion
of the Premises and the issuance of a certificate of occupancy or its legal
equivalent allowing occupancy of the

                              EXHIBIT B - Page 4

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<PAGE>

Premises. For purposes of this Lease, "Substantial Completion" of the Premises
shall occur upon the completion of construction of the Tenant Improvements in
the Premises pursuant to the Approved Working Drawings, with the exception of
any punch list items and any tenant fixtures, work-stations, built-in furniture,
or equipment to be installed by Tenant.

     5.2  Delay of the Substantial Completion of the Premises.  Except as
provided in this Section 5.2, the Lease Commencement Date shall occur as set
forth in the Lease and Section 5.1, above.  If there shall be a delay or there
are delays in the Substantial Completion of the Premises or in the occurrence of
any of the other conditions precedent to the Lease Commencement Date, as set
forth in the Lease, as a direct, indirect, partial, or total result of:

          5.2.1  Tenant's failure to comply with the Time Deadlines;

          5.2.2  Tenant's failure to timely approve any matter requiring
Tenant's approval;

          5.2.3  A breach by Tenant of the terms of this Tenant Work Letter
or the Lease;

          5.2.4  Changes in any of the Construction Drawings after disapproval
of the same by Landlord or because the same do not comply with Code or other
applicable laws;

          5.2.5  Tenant's request for changes in the Approved Working
Drawings;

          5.2.6  Tenant's requirement for materials, components, finishes or
improvements which are not available in a commercially reasonable time given the
anticipated date of Substantial Completion of the Premises, as set forth in the
Lease, or which are different from, or not included in, the Standard Improvement
Package;

          5.2.7  Changes to the Base, Shell and Core required by the
Approved Working Drawings; or

          5.2.8  Any other acts or omissions of Tenant, or its agents, or
employees;

then, notwithstanding anything to the contrary set forth in the Lease or this
Tenant Work Letter and regardless of the actual date of the Substantial
Completion of the Premises, the Lease Commencement Date shall be deemed to be
the date the Lease Commencement Date would have occurred if no Tenant delay or
delays, as set forth above, had occurred.

                                   SECTION 6
                                   ---------

                                 MISCELLANEOUS
                                 -------------

     6.1  Tenant's Entry Into the Premises Prior to Substantial Completion.
Provided that Tenant and its agents do not interfere with Contractor's work in
the Building and the Premises, Contractor shall allow Tenant access to the
Premises prior to the Substantial Completion of the

                              EXHIBIT B - Page 5

                                                      IRVINE OAKS EXECUTIVE PARK
                                                          [MicroSim Corporation]
<PAGE>

Premises for the purpose of Tenant installing overstandard equipment or fixtures
(including Tenant's data and telephone equipment) in the Premises, and,
furthermore, Landlord agrees that in no event shall the Premises be deemed Ready
for Occupancy prior to the date which is thirty (30) days after the date Tenant
is granted such access. Prior to Tenant's entry into the Premises as permitted
by the terms of this Section 6.1, Tenant shall submit a schedule to Landlord and
Contractor, for their approval, which schedule shall detail the timing and
purpose of Tenant's entry. Tenant shall hold Landlord harmless from and
indemnify, protect and defend Landlord against any loss or damage to the
Building or Premises, or damage to Tenant's furniture, fixtures or equipment, or
personal property, and against injury to any persons caused by Tenant's actions
pursuant to this Section 6.1.

     6.2  Freight Elevators.  Landlord shall make the freight elevator, after
the same has been installed and completed, reasonably available to Tenant in
connection with initial decorating, furnishing and moving into the Premises.

     6.3  Tenant's Representative.  Tenant has designated Wendi Hall as its sole
representative with respect to the matters set forth in this Tenant Work Letter,
who, until further notice to Landlord, shall have full authority and
responsibility to act on behalf of the Tenant as required in this Tenant Work
Letter.

     6.4  Landlord's Representative.  Landlord has designated James Dawson as
its sole representatives with respect to the matters set forth in this Tenant
Work Letter, who, until further notice to Tenant, shall have full authority and
responsibility to act on behalf of the Landlord as required in this Tenant Work
Letter.

     6.5  Time of the Essence in This Tenant Work Letter.  Unless otherwise
indicated, all references herein to a "number of days" shall mean and refer to
calendar days.  In all instances where Tenant is required to approve or deliver
an item, if no written notice of approval is given or the item is not delivered
within the stated time period, at Landlord's sole option, at the end of such
period the item shall automatically be deemed approved or delivered by Tenant
and the next succeeding time period shall commence.

     6.6  Tenant's Lease Default.  Notwithstanding any provision to the contrary
contained in this Lease, if an event of default as described in the Lease, or a
default by Tenant under this Tenant Work Letter, has occurred at any time on or
before the Substantial Completion of the Premises, then (i) in addition to all
other rights and remedies granted to Landlord pursuant to the Lease, Landlord
shall have the right to withhold payment of all or any portion of the Tenant
Improvement Allowance and/or Landlord may cause Contractor to cease the
construction of the Premises (in which case, Tenant shall be responsible for any
delay in the Substantial Completion of the Premises caused by such work stoppage
as set forth in Section 5 of this Tenant Work Letter), and (ii) all other
obligations of Landlord under the terms of this Tenant Work Letter shall be
forgiven until such time as such default is cured pursuant to the terms of the
Lease.

                              EXHIBIT B - Page 6

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<PAGE>

                            SCHEDULE 1 TO EXHIBIT B
                            -----------------------

                                 TIME DEADLINES
                                 --------------
               Dates                            Actions to be Performed
               -----                            -----------------------

A.  Completed.                              Final Space Plan to be completed by
                                            Tenant and delivered to Landlord.

B.  Five (5) business days after the        Tenant to approve Cost Proposal and
    receipt of the Cost Proposal by         delivery Cost Proposal to Landlord.
    Tenant

                       SCHEDULE 1 TO EXHIBIT B - Page 1

                                                      IRVINE OAKS EXECUTIVE PARK
                                                          [MicroSim Corporation]
<PAGE>

                            SCHEDULE 2 TO EXHIBIT B
                            -----------------------

                                  DESIGN PLANS
                                  ------------

     The Base, Shell and Core of the Building is to be constructed pursuant to
     those certain Shell Plans prepared by Datum Architects for Irvine Oaks
     Executive Park - MicroSim, and dated November 18, 1996.

                       SCHEDULE 2 TO EXHIBIT B - Page 1

                                                      IRVINE OAKS EXECUTIVE PARK
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<PAGE>

                            SCHEDULE 3 TO EXHIBIT B
                            -----------------------

                                 SPECIFICATIONS
                                 --------------

                   TENANT IMPROVEMENT STANDARDS - IRVINE OAKS
                   ------------------------------------------


     DEMISING PARTITION
     ------------------

     a.   4" - 25 gauge metal studs - 16" on center.
     b.   5/8" drywall type "x" one layer tenant side only.
     c.   Height from floor slab to structure above.
     d.   Partition taped smooth to receive paint.
     e.   Batt insulation in cavity, R-11 to undersize of structure.

     INTERIOR PARTITION OFFICE
     -------------------------

     a.   2 1/2" - 25 gauge studs - 24" on center.
     b.   5/8" drywall - one layer each side of studs.
     c.   Height from floor slab to ceiling above.
     d.   Partition taped smooth to receive paint to underside of suspended
          ceiling.
     e.   Brake metal cap with neoprene gasket at exterior glazing.

     INTERIOR DOOR ASSEMBLY
     ----------------------

     a.   Door 0 3'-0 x 8' x a-3/4" solid core, plain sliced red oak veneer with
          matching edge band.
     b.   Frame - 3'-0" x 8'-0" "TIMELY" black factory painted.  Throat size to
          fit wall.
     c.   Latch set - Schlage-Rhodes 10-S 625 lever with matching strike finish
          to match existing.
     d.   Hinges - RC 700 4 x 4 625 hagar or equal (4 per door).
     e.   Stop - Builders Brass Works #8061 with riser or equal (Floor Stop).

     RATED DOOR ASSEMBLIES
     ---------------------

     a.   Door - 3"-0" x 8'-0" solid core 20 minute label, plain sliced red oak
          veneer w/matching edge band.
     b.   Frame - 3'-0" x 8'-0" "TIMELY", 20 minute rated, Black factory
          painted. Throat size to fit wall.
     c.   Lock set - Schlage Rhodes D-53 625 lever ""key way with matching
          strike.
     d.   Closer - 4010N x cover c al arm LCN or equal.
     e.   Hinges - BB RC 700 4x4x625 hagar or equal.

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     f.   Door Stop - Builders Brass Works #8061 with riser or equal (Floor
          Stop).
     g.   Astrigals - Pemco 355 alm finish.  (At pair of doors).
     h.   Dust proof strikes - D.P.2 Glenn Johnson (At pair of doors).
     j.   Flush bolts FB8 - Glenn Johnson (At pair of doors).

     ACOUSTICAL CEILING
     ------------------

     a.   2' x 2' Donn Meridian intermediate duty T-Bar suspension system, matte
          white finish, at approximately 9'-0" AFF.
     b.   2' x 2' U.S.G. Auratone #344 "Omni Fissured" 5/8" with grid edge, lay-
          in-type with shoulder flush with grid.
     c.   Wire suspension per code.

          Allowance:  Ceiling throughout office areas.

     FIRE SPRINKLERS
     ---------------

     a.   Semi-recessed head, with flush-mounted chrome escutcheon.
     b.   Drop heads from existing distribution, relocate as required.
     c.   Engineering as required.
     d.   Concealed white escutcheons at drywall ceilings.

     FLOOR COVERING
     --------------

     a.   *Carpet-1, Mannington Commercial "Intergraph 26" direct glue.
     b.   Carpet-2, Designweave, "New Temptest" direct glue.
     c.   Vinyl Composition Tile (VCT) "Armstrong" Imperial Texture
          12" x 12" x 1/8".
     d.   Sheet Vinyl 'Armstrong" Classic Corolon -Suffield.
     *    Paul Singer is an exclusive provider

     RUBBER TOPSET BASE
     ------------------

     a.   4" Rubber topset base, Burke.
     b.   Any standard commercial color.

     PAINTING
     --------

     a.   Two coats flat interior latex paint.
     b.   Doors stain and lacquer.

     EXIT SIGNS
     ----------

     a.   "MARCO" universal exit sign with battery pack, white housing with
          green letters, ceiling mounted.

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     WINDOW COVERING
     ---------------

     a.   1" aluminum mini-blinds - Levelor "Riviera," white (or equal).

     Allowance:  All exterior building glazing throughout office area.

     TENANT SIGNAGE
     --------------

     a.   Signage to be provided by Tenant.

     H.V.A.C.
     --------

     a.   Supply registers - Kruger 6500 series, white to match T-bar.
     b.   Thermostats - Honeywell T-7300 programable.

     2' X 4' FLUORESCENT LIGHT FIXTURE
     ---------------------------------

     a.   2' x 4' "Lithonia" lay-in type, 2GT-332-A12-(120V/277V)-GEB-LST.
          (3) Fo32-T8 lamps, with electronic ballast, prismatic lens or
          approved equal.
     b.   Wire suspension per code.
     c.   Switching per Title 24.
     d.   Design and engineer electrical per Title 24.
     e.   Connect one fixture per 2,000 sq. ft. to emergency lighting system.

     8' FLUORESCENT LIGHT FIXTURE - WAREHOUSE
     ----------------------------------------

     a.   8' "Lithonia", EJA-296-PG 120/277 ES, 2F96 cool white lamps.
     b.   Wire suspension per code.
     c.   Switching per Title 24.
     d.   Design and engineer electrical per Title 24.
     e.   Connect one fixture per 2,000 sq. ft. to emergency lighting system.

     LIGHTING SWITCH ASSEMBLY
     ------------------------

     a.   "Leviton," Decora, #5600 Series, or equal, white toggle and cover
          plate.
     b.   Switches paired in double gang box per Title 24 requirements.
          (California)
     c.   Mounted 42" AFF, to center of switch.

     ELECTRICAL WALL OUTLET
     ----------------------

     a.   "Levitron," #5600-sw or equal, duplex receptacle, 1 each - white
          receptacle and cover plate.
     b.   Mounted vertically.

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     c.   Outlet height at 15" AFF to underside of outlet.
     d.   Design and engineer electrical per Title 24.  (California)

     TELEPHONE WALL OUTLET
     ---------------------

     a.   Single gang box in wall - mounted vertically at 15" AFF to underside
          of box.
     b.   3/4" metal conduit up wall stubbed 6" above ceiling.
     c.   With pull string and ring.
     d.   Cover plate by Tenant's telephone company.

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                                   EXHIBIT C
                                   ---------

                           IRVINE OAKS EXECUTIVE PARK
                           --------------------------

                           NOTICE OF LEASE TERM DATES
                           --------------------------


To:  _______________________

     _______________________

     _______________________

     _______________________


     Re:  Office Lease dated ____________, 19__ between ____________________, a
          ________________________ ("Landlord"), and _______________________, a
          ______________________ ("Tenant") concerning Suite ______ on floor(s)
          __________ of the office building located at ________________________
          Los Angeles, California.

Gentlemen:

     In accordance with the Office Lease (the "Lease"), we wish to advise you
and/or confirm as follows:

     1.   The Lease Term shall commence on or has commenced on ______________
          for a term of __________________ ending on __________________.

     2.   Rent commenced to accrue on __________________, in the amount of
          ________________.

     3.   If the Lease Commencement Date is other than the first day of the
          month, the first billing will contain a pro rata adjustment.  Each
          billing thereafter, with the exception of the final billing, shall be
          for the full amount of the monthly installment as provided for in the
          Lease.

     4.   Your rent checks should be made payable to __________________ at
          ___________________.

     5.   The exact number of rentable/usable square feet within the Premises is

          ____________ square feet.

                              EXHIBIT C - Page 1

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     6.   Tenant's Share as adjusted based upon the exact number of usable
          square feet within the Premises is ________%.


                                       "Landlord":
                                       ________________________________________

                                       a ______________________________________

                                       By: ____________________________________

                                          Its:_________________________________

Agreed to and Accepted
as of ____________, 19___.

"Tenant":

_____________________________________

a ___________________________________

By: _________________________________

   Its:______________________________

                              EXHIBIT C - Page 2

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                                   EXHIBIT D
                                   ---------

                           IRVINE OAKS EXECUTIVE PARK
                           --------------------------

                             RULES AND REGULATIONS
                             ---------------------

     Tenant shall faithfully observe and comply with the following Rules and
Regulations.  Landlord shall not be responsible to Tenant for the nonperformance
of any of said Rules and Regulations by or otherwise with respect to the acts or
omissions of any other tenants or occupants of the  Project.  In the event of
any conflict between the Rules and Regulations and the other provisions of this
Lease, the latter shall control.

     1.   Tenant shall not alter any lock or install any new or additional locks
or bolts on any doors or windows of the Premises without obtaining Landlord's
prior written consent.  Tenant shall bear the cost of any lock changes or
repairs required by Tenant.  Two keys will be furnished by Landlord for the
Premises, and any additional keys required by Tenant must be obtained from
Landlord at a reasonable cost to be established by Landlord.  Upon the
termination of this Lease, Tenant shall restore to Landlord all keys of stores,
offices, and toilet rooms, either furnished to, or otherwise procured by, Tenant
and in the event of the loss of keys so furnished, Tenant shall pay to Landlord
the cost of replacing same or of changing the lock or locks opened by such lost
key if Landlord shall deem it necessary to make such changes.

     2.   All doors opening to public corridors shall be kept closed at all
times except for normal ingress and egress to the Premises.

     3.   Landlord reserves the right to close and keep locked all entrance and
exit doors of the Building non-business hours. Tenant, its employees and agents
must be sure that the doors to the Building are securely closed and locked when
leaving the Premises if it is after the normal hours of business for the
Building. In case of invasion, mob, riot, public excitement, or other commotion,
Landlord reserves the right to prevent access to the Building or the Project
during the continuance thereof by any means it deems appropriate for the safety
and protection of life and property.

     4.   The requirements of Tenant will be attended to only upon application
at the management office for the Project or at such office location designated
by Landlord. Employees of Landlord shall not perform any work or do anything
outside their regular duties unless under special instructions from Landlord.

     5.   No sign, advertisement, notice or handbill shall be exhibited,
distributed, painted or affixed by Tenant on any part of the Premises or the
Building without the prior written consent of the Landlord.  Tenant shall not
disturb, solicit, peddle, or canvass any occupant of the Project and shall
cooperate with Landlord and its agents of Landlord to prevent same.

     6.   The toilet rooms, 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

                              EXHIBIT D - Page 1

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kind whatsoever shall be thrown therein. The expense of any breakage, stoppage
or damage resulting from the violation of this rule shall be borne by the tenant
who, or whose servants, employees, agents, visitors or licensees shall have
caused same.

     7.   Except for vending machines intended for the sole use of Tenant's
employees and invitees, no vending machine or machines other than fractional
horsepower office machines shall be installed, maintained or operated upon the
Premises without the written consent of Landlord.

     8.   Subject to Article 5 of this Lease, Tenant shall not use or keep in or
on the Premises, the Building, or the Project any kerosene, gasoline or other
inflammable or combustible fluid, chemical, substance or material, except in
connection with a propane powered forklift to be kept in the Building by Tenant,
provided that Tenant complies with all applicable laws with respect to the use
and storage of the same.

     9.   Tenant shall not without the prior written consent of Landlord use any
method of heating or air conditioning other than that supplied by Landlord.

     10.  Tenant shall not use, keep or permit to be used or kept, any foul or
noxious gas or substance in or on the Premises, or permit or allow the Premises
to be occupied or used in a manner offensive or objectionable to Landlord or
other occupants of the Project by reason of noise, odors, or vibrations, or
interfere with other tenants or those having business therein, whether by the
use of any musical instrument, radio, phonograph, or in any other way.  Tenant
shall not throw anything out of doors, windows or skylights or down passageways.

     11.  Tenant shall not bring into or keep within the Project, the Building
or the Premises any animals, birds, aquariums.

     12.  No cooking shall be done or permitted on the Premises, nor shall the
Premises be used for the storage of merchandise, for lodging or for any
improper, objectionable or immoral purposes.  Notwithstanding the foregoing,
Underwriters' laboratory-approved equipment and microwave ovens may be used in
the Premises for heating food and brewing coffee, tea, hot chocolate and similar
beverages for employees and visitors, provided that such use is in accordance
with all applicable federal, state, county and city laws, codes, ordinances,
rules and regulations.

     13.  The Premises shall not be used for the storage of merchandise except
as such storage may be incidental to the use of the Premises provided for in the
Summary.

     14.  Landlord reserves the right to exclude or expel from the Project any
person who, in the judgment of Landlord, is intoxicated or under the influence
of liquor or drugs, or who shall in any manner do any act in violation of any of
these Rules and Regulations.

     15.  Tenant, its employees and agents shall not loiter in or on the
entrances, corridors, sidewalks, lobbies, courts, halls, stairways, elevators,
vestibules or any Common Areas for the purpose of smoking tobacco products or
for any other purpose, nor in any way obstruct such areas, and shall use them
only as a means of ingress and egress for the Premises.

                              EXHIBIT D - Page 2

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     16.  Tenant shall not waste electricity, water or air conditioning and
agrees to cooperate fully with Landlord to ensure the most effective operation
of the Building's heating and air conditioning system.

     17.  No material shall be placed in the trash boxes or receptacles if such
material is of such nature that it may not be disposed of in the ordinary and
customary manner of removing and disposing of trash and garbage in Irvine,
California without violation of any law or ordinance governing such disposal.
All trash, garbage and refuse disposal shall be made only through entry-ways and
elevators provided for such purposes as Landlord shall designate.

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

     19.  Any persons employed by Tenant to do janitorial work shall be subject
to the prior written approval of Landlord.

     20.  No awnings or other projection shall be attached to the outside walls
of the Building without the prior written consent of Landlord, and no curtains,
blinds, shades or screens shall be attached to or hung in, or used in connection
with, any window or door of the Premises other than Landlord standard drapes.
All electrical ceiling fixtures hung in the Premises or spaces along the
perimeter of the Building must be fluorescent and/or of a quality, type, design
and a warm white bulb color approved in advance in writing by Landlord.  Neither
the interior nor exterior of any windows shall be coated or otherwise
sunscreened without the prior written consent of Landlord.  Tenant shall abide
by Landlord's regulations concerning the opening and closing of window coverings
which are attached to the windows in the Premises, if any, which have a view of
any interior portion of the Building or Building Common Areas.

     21.  The sashes, sash doors, skylights, windows, and doors that reflect or
admit light and air into the halls, passageways or other public places in the
Building shall not be covered or obstructed by Tenant, nor shall any bottles,
parcels or other articles be placed on the windowsills.

     22.  Tenant must comply with requests by the Landlord concerning the
informing of their employees of items of importance to the Landlord.

     23.  Tenant hereby acknowledges that Landlord shall have no obligation to
provide guard service or other security measures for the benefit of the
Premises, the Building or the Project.  Tenant hereby assumes all responsibility
for the protection of Tenant and its agents, employees, contractors, invitees
and guests, and the property thereof, from acts of third parties, including
keeping doors locked and other means of entry to the Premises closed, whether or
not Landlord, at its option, elects to provide security protection for the
Project or any portion thereof.  Tenant further assumes the risk that any safety
and security devices, services and programs which Landlord elects, in its sole
discretion, to provide may not be effective, or may malfunction or be
circumvented by an unauthorized third party, and Tenant shall, in addition to
its other insurance obligations under this Lease, obtain its own insurance
coverage to the extent Tenant

                              EXHIBIT D - Page 3

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desires protection against losses related to such occurrences. Tenant shall
cooperate in any reasonable safety or security program developed by Landlord or
required by law.

     24.  All office equipment of any electrical or mechanical nature shall be
placed by Tenant in the Premises in settings approved by Landlord, to absorb or
prevent any vibration, noise and annoyance.

     25.  Tenant shall not use in any space or in the public halls of the
Building, any hand trucks except those equipped with rubber tires and rubber
side guards.

     26.  No auction, liquidation, fire sale, going-out-of-business or
bankruptcy sale shall be conducted in the Premises without the prior written
consent of Landlord.

     27.  No tenant shall use or permit the use of any portion of the Premises
for living quarters, sleeping apartments or lodging rooms.

     Landlord reserves the right at any time to change or rescind any one or
more of these Rules and Regulations, or to make such other and further
reasonable Rules and Regulations as in Landlord's judgment may from time to time
be necessary for the management, safety, care and cleanliness of the Premises,
Building, the Common Areas and the Project, and for the preservation of good
order therein, as well as for the convenience of other occupants and tenants
therein.  Landlord may waive any one or more of these Rules and Regulations for
the benefit of any particular tenants, but no such waiver by Landlord shall be
construed as a waiver of such Rules and Regulations in favor of any other
tenant, nor prevent Landlord from thereafter enforcing any such Rules or
Regulations against any or all tenants of the  Project.  Tenant shall be deemed
to have read these Rules and Regulations and to have agreed to abide by them as
a condition of its occupancy of the Premises.

                              EXHIBIT D - Page 4

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                                   EXHIBIT E
                                   ---------

                           IRVINE OAKS EXECUTIVE PARK
                           --------------------------

                     FORM OF TENANT'S ESTOPPEL CERTIFICATE
                     -------------------------------------

     The undersigned as Tenant under that certain Office Lease (the "Lease")
made and entered into as of ___________, 199   by and between _______________ as
Landlord, and the undersigned as Tenant, for Premises on the ______________
floor(s) of the office building located at ______________, Irvine, California
____________, certifies as follows:

     1.   Attached hereto as Exhibit A is a true and correct copy of the Lease
and all amendments and modifications thereto.  The documents contained in
Exhibit A represent the entire agreement between the parties as to the Premises.

     2.   The undersigned currently occupies the Premises described in the
Lease, the Lease Term commenced on __________, and the Lease Term expires on
___________.

     3.   Base Rent became payable on ____________.

     4.   The Lease is in full force and effect and has not been modified,
supplemented or amended in any way except as provided in Exhibit A.

     5.   Tenant has not transferred, assigned, or sublet any portion of the
Premises nor entered into any license or concession agreements with respect
thereto except as follows:

     6.   Tenant shall not modify the rent or insurance provisions of the
documents contained in Exhibit A without the prior written consent of Landlord's
mortgagee.

     7.   All monthly installments of Base Rent, all Additional Rent and all
monthly installments of estimated Additional Rent have been paid when due
through ___________.  The current monthly installment of Base Rent is
$_____________________.

     8.   All conditions of the Lease to be performed by Landlord necessary to
the enforceability of the Lease have been satisfied and Landlord is not in
default thereunder.

     9.   No rental has been paid more than thirty (30) days in advance and no
security has been deposited with Landlord except as provided in the Lease.

                              EXHIBIT E - Page 1

                                                      IRVINE OAKS EXECUTIVE PARK
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     10.  As of the date hereof, there are no existing defenses or offsets that
the undersigned has against Landlord.

     11.  If Tenant is a corporation or partnership, each individual executing
this Estoppel Certificate on behalf of Tenant hereby represents and warrants
that Tenant is a duly formed and existing entity qualified to do business in
California and that Tenant has full right and authority to execute and deliver
this Estoppel Certificate and that each person signing on behalf of Tenant is
authorized to do so.

     The undersigned acknowledges that this Estoppel Certificate may be
delivered to Landlord or to a prospective mortgagee or prospective purchaser,
and acknowledges that said prospective mortgagee or prospective purchaser will
be relying upon the statements contained herein in making the loan or acquiring
the property of which the Premises are a part and that receipt by it of this
certificate is a condition of making such loan or acquiring such property.

Executed at ______________ on the ____ day of ___________, 19  .


                                       "Tenant":

                                       _________________________________________

                                       a _______________________________________

                                       By:______________________________________

                                          Its:__________________________________

                                       By: _____________________________________

                                          Its:__________________________________


                              EXHIBIT E - Page 2

                                                      IRVINE OAKS EXECUTIVE PARK
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                                  OFFICE LEASE
                                  ------------


                           IRVINE OAKS EXECUTIVE PARK
                           --------------------------



                   MAGELLAN IRVINE OAKS LIMITED PARTNERSHIP,

                        an Arizona limited partnership,

                                  as Landlord,

                                      and

                             MICROSIM CORPORATION,

                           a California corporation,

                                   as Tenant.



                                                      IRVINE OAKS EXECUTIVE PARK
                                                          [MicroSim Corporation]

<PAGE>

                           IRVINE OAKS EXECUTIVE PARK
                           --------------------------

                                     INDEX
                                     -----


ARTICLE       SUBJECT MATTER                                         PAGE
-------       --------------                                         ----

ARTICLE 1     PREMISES, BUILDING, PROJECT, AND
              COMMON AREAS..........................................   6
ARTICLE 2     LEASE TERM; OPTION TERMS..............................   9
ARTICLE 3     BASE RENT.............................................  10
ARTICLE 4     ADDITIONAL RENT.......................................  11
ARTICLE 5     USE OF PREMISES.......................................  17
ARTICLE 6     SERVICES AND UTILITIES................................  17
ARTICLE 7     MAINTENANCE AND REPAIRS...............................  19
ARTICLE 8     ADDITIONS AND ALTERATIONS.............................  21
ARTICLE 9     COVENANT AGAINST LIENS................................  23
ARTICLE 10    INSURANCE.............................................  23
ARTICLE 11    DAMAGE AND DESTRUCTION................................  26
ARTICLE 12    NONWAIVER.............................................  28
ARTICLE 13    CONDEMNATION..........................................  28
ARTICLE 14    ASSIGNMENT AND SUBLETTING.............................  29
ARTICLE 15    SURRENDER OF PREMISES; OWNERSHIP AND
              REMOVAL OF TRADE FIXTURES.............................  33
ARTICLE 16    HOLDING OVER..........................................  34
ARTICLE 17    ESTOPPEL CERTIFICATES.................................  34
ARTICLE 18    SUBORDINATION.........................................  35
ARTICLE 19    DEFAULTS; REMEDIES....................................  36
ARTICLE 20    COVENANT OF QUIET ENJOYMENT...........................  39
ARTICLE 21    SECURITY DEPOSIT......................................  39
ARTICLE 22    INTENTIONALLY OMITTED.................................  41
ARTICLE 23    SIGNS.................................................  41
ARTICLE 24    COMPLIANCE WITH LAW...................................  41
ARTICLE 25    LATE CHARGES..........................................  42
ARTICLE 26    LANDLORD'S RIGHT TO CURE DEFAULT;
              PAYMENTS BY TENANT....................................  42
ARTICLE 27    ENTRY BY LANDLORD.....................................  43
ARTICLE 28    TENANT PARKING........................................  43
ARTICLE 29    MISCELLANEOUS PROVISIONS..............................  44

                                     (ii)


                                                      IRVINE OAKS EXECUTIVE PARK
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<PAGE>

EXHIBITS

A  OUTLINE OF PREMISES

B  TENANT WORK LETTER

C  FORM OF NOTICE OF LEASE TERM DATES

D  RULES AND REGULATIONS

E  FORM OF TENANT'S ESTOPPEL CERTIFICATE

                                     (iii)

                                                      IRVINE OAKS EXECUTIVE PARK
                                                          [MicroSim Corporation]
<PAGE>

                           IRVINE OAKS EXECUTIVE PARK
                           --------------------------

                          INDEX OF MAJOR DEFINED TERMS
                          ----------------------------
                                                              LOCATION OF
                                                              DEFINITION IN
DEFINED TERMS                                                 OFFICE LEASE
-------------                                                 -------------
Abatement Event..................................................  38
Additional Rent..................................................  11
Alterations......................................................  20
Base Building....................................................  21
Base Rent........................................................  10
Brokers..........................................................  47
Building.........................................................   6
Building Direct Expenses.........................................  11
Building Operating Expenses......................................  11
Building Tax Expenses............................................  11
Common Areas.....................................................   7
Cosmetic Alterations.............................................  21
Cost Pools.......................................................  15
Direct Expenses..................................................  12
Effective Date...................................................  10
Eligibility Period...............................................  38
Estimate.........................................................  15
Estimate Statement...............................................  15
Estimated Payment................................................  15
Expansion Rent...................................................   8
Expansion Rent Notice............................................   7
Expansion Space..................................................   7
Expense Payment..................................................  15
Expense Year.....................................................  12
Force Majeure....................................................  46
Irvine Oaks Executive Park.......................................   6
Landlord.........................................................   1
Landlord Parties.................................................  23
Lease............................................................   1
Lease Commencement Date..........................................   9
Lease Expiration Date............................................   9
Lease Term.......................................................   9
Lease Year.......................................................   9
Mail.............................................................  46
Mortgagees.......................................................  35
Notices..........................................................  46

                                     (iv)

                                                      IRVINE OAKS EXECUTIVE PARK
                                                          [MicroSim Corporation]
<PAGE>

Operating Expenses...............................................  12
Option Rent......................................................   9
Option Rent Notice...............................................  10
Option Term......................................................   9
Original Improvements............................................  24
Other Improvements...............................................  48
Outside Date.....................................................  10
Premises.........................................................   6
Project..........................................................   6
Project Direct Expenses..........................................  11
Proposition 13...................................................  13
Renovations......................................................  49
Rent.............................................................  11
rentable square feet.............................................   7
Security Deposit.................................................  39
Statement........................................................  15
Subject Space....................................................  29
Summary..........................................................   1
Tax Expenses.....................................................  13
Tenant...........................................................   1
Tenant Parties...................................................  23
Tenant Work Letter...............................................   6
Tenant's Building Share..........................................  14
Tenant's Project Share...........................................  14
Tenant's Subleasing Costs........................................  31
Termination Notice...............................................  10
Transfer.........................................................  32
Transfer Notice..................................................  29
Transfer Premium.................................................  31
Transferee.......................................................  29
Transfers........................................................  29

                                      (v)

                                                      IRVINE OAKS EXECUTIVE PARK
                                                          [MicroSim Corporation]