Document:

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                                                                Exhibit 10.13

                                NET OFFICE LEASE

                      FIRST BROADWAY/20TH, LLC, AS LANDLORD

                                       AND

                             DOUBLETWIST, AS TENANT

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                                      LEASE
                             BASIC LEASE INFORMATION

<TABLE>
<S>                                                                                     <C>
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                                                                                        LEASE REFERENCE
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Effective Date: April 12, 2000
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Landlord:

         First Broadway/20th, LLC,
         a California limited liability company
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Tenant DoubleTwist Inc., a California corporation
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Premises and Building Address:                                                          Paragraph 1

         2001 Broadway
         Oakland, California 94612
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Approximate Area of Premises:  63,486 square feet
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Estimated Term Commencement:  October 1, 2000                                           Paragraph 2
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Estimated Term Expiration: September 30,2010                                            Paragraph 2
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Monthly Base Rent:                                                                      Paragraph 3 (a)
LEASE YEAR                                   AMOUNT

         Months        1-12                           146,570
         Months       13-24                           151,440
         Months       25-36                           156,480
         Months       37-48                           161,700
         Months       49-60                           167,100
         Months       61-72                           172,690
         Months       73-84                           178,480
         Months       85-96                           184,470
         Months      97-108                           190,670
         Months     109-120                           197,080
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Use:. General office uses, except for minor portion of ground floor required under      Paragraph 6(a)
zoning to be used for retail use, and other legal uses
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Security Deposit:  $400,000 letter of credit                                            Paragraph 16
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Tenant's Address for Notices:                                                           Paragraph 21
         Before Commencement Date:
         1999 Harrison Street, Suite 1100
         Oakland, CA 94612
         Telecopier No. (510) 628-0110
         Attn: General Counsel

         After Commencement Date:
         2001 Broadway
         Oakland, CA 94612
         Attn: General Counsel
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Landlord's Address for Notices (AND ADDRESS FOR PAYMENT OF RENT):

         Before Commencement Date:
         First Broadway/20th LLC
         1125 Atlantic Avenue, Suite 102
         Alameda, CA 94501
         Telecopier No. (510) 864-1020

         After Commencement Date:
         First Broadway/20th LLC
         3270 Lakeshore Avenue
         Oakland, CA 94610
         Attn: Steve Meckfessel
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With a copy to:

         Thelen Reid & Priest
         101 Second Street, Suite 1800
         San Francisco, CA 94105-3601
         Attn: Richard Shapiro
         Telecopier No. (415) 371-1211
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Exhibits:

         Exhibit A - Outline of Leased Premises
         Exhibit B - Initial Improvement of the premises
         Exhibit B-1 Description of Landlord's Work
         Exhibit C - Verification Memorandum
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</TABLE>

The Provisions of the Lease identified above in the margin are those provisions
where references to particular Basic Lease Information appear. Each such
reference shall incorporate the applicable Basic Lease to Information. In the
event of any conflict between any Basic Lease Information and the Lease, the
latter shall control.

                                      B-2
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                                      LEASE

         THIS LEASE ("Lease") is made and entered into as of the Effective Date
by and between First Broadway/20th, LLC, a California limited liability company
("Landlord"), and DoubleTwist, Inc., a California corporation ("Tenant").

                                   WITNESSETH

         1. PREMISES. Landlord hereby leases to Tenant, and Tenant hereby leases
from Landlord for the term of this Lease and at the rental and upon the
conditions set forth below, the Premises described in the Basic Lease
Information and identified approximately on the drawings attached hereto as
Exhibit A. The Premises are located within the building identified in the Basic
Lease Information (the "Building"). Landlord warrants and represents that, as of
the Commencement Date, (i) the Premises will comply with all applicable laws,
rules, regulations, codes, ordinances, underwriters' requirements, covenants
conditions and restrictions (ii) the Premises will be in good and clean
operating condition and repair, (iii) the electrical, mechanical, HVAC,
plumbing, sewer, elevator and other systems serving the Premises will be in good
operating condition and repair, and (iv) the roof of the Premises will be in
good condition and water tight. Tenant shall notify Landlord in writing, within
one (1) year after the Commencement Date of this Lease, of any defects in the
Premises claimed by Tenant or in the materials or workmanship furnished by
Landlord in completing the Tenant Improvements or Landlord's Work. Except for
defects stated in such notices, Tenant shall be conclusively deemed to have
accepted the Premises "AS IS", in the condition existing on the date Tenant
first takes possession, and to have waived all claims relating to the condition
of the Premises. Landlord shall proceed diligently to correct the defects stated
in such notice unless Landlord disputes the existence of any such defects. In
the event of any dispute as to the existence of any such defects, the decision
of Landlord's architect shall be final and binding on the parties. Landlord and
Tenant hereby agree that Tenant shall receive the benefit of any and all
warranties with respect to the Landlord's Work and Tenant Improvements.

         2.  TERM.

                  (a) COMMENCEMENT. The Lease shall commence on the date (the
"Commencement Date") that is the later of October 1, 2000, or (unless waived by
Tenant in writing) the date by which all of the following have occurred: (a)
Landlord has substantially completed the Landlord's Work and the Tenant
Improvements in accordance with the Lease and Exhibits hereto, (b) Landlord has
delivered possession of the Premises to Tenant; and (c) Landlord has obtained
all approvals and permits from the appropriate governmental authorities required
for the legal occupancy of the Premises for general office use. The foregoing
notwithstanding, the Commencement Date shall be accelerated by the number of
days, if any, due to Tenant Delay. If Landlord shall permit

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Tenant to occupy the Premises prior to the Commencement Date, such occupancy
will be subject to all the term of this Lease, except the obligation to pay
rent. If Landlord, for any reason whatsoever, cannot deliver possession of the
Premises to Tenant on the Commencement Date, this Lease shall not be void or
voidable, nor shall Landlord be liable to Tenant for any loss or damage
resulting therefrom but in that event subject to any contrary provisions in any
agreement with Landlord covering initial improvement of the Premises, rental
shall be waived for the period between commencement of the term and the time
when Landlord can deliver possession. The date of term expiration shall be
extended by the number of days of delay in delivery of possession and any
additional period required so that it will expire on the last day of a calendar
month, and the commencement and expiration dates shall be confirmed in a
Verification Memorandum in the form of Exhibit C executed by Landlord and Tenant
promptly following delivery of possession.

                  (b) OPTION TO PURCHASE BUILDING IF LANDLORD UNABLE TO SECURE
FINANCING. Notwithstanding anything in this Lease to the contrary, in the event
Landlord is unable to secure satisfactory financing through Silicon Valley Bank
on or before June 1, 2000, then Tenant shall have the option to purchase the
Building and the underlying land from Landlord. Such purchase option must be
exercised on or before June 10, 2000 and, if not exercised by Tenant within such
ten (10) day period, shall terminate and be no longer valid. Tenant shall
purchase the Building subject to any encumbrances then existing on the Building
and underlying land and upon repayment to Landlord of the amount of its initial
capital contributions actually expended by Landlord for the purchase, design and
construction of the Building (including fees to SRM Associates for time expended
based on SRM Associates' standard billing rates), all accrued interest thereon
(at the rate of fifteen (15%) per annum) and payment of all closing costs
associated with such transfer.

                  (b) OPTION TO PURCHASE BUILDING IF NOT TIMELY DELIVERED.
Notwithstanding the foregoing, in the event that the Commencement Date has not
occurred on or before December 1, 2000 ("Outside Delivery Date"), which date
shall be extended by the number of days, if any, of Tenant Delay or causes
beyond the reasonable control of Landlord, then Tenant shall have the option to
purchase the Building and the underlying land from Landlord. Such purchase
option must be exercised within thirty (30) days of the Outside Delivery Date
and, if not exercised by Tenant within such thirty (30) day period, shall
terminate and be no longer valid. Tenant shall purchase the Building subject to
any encumbrances existing as of the Outside Delivery Date (including any
mortgages or deed of trust) and upon repayment to Landlord of the amount of its
initial capital contributions actually expended by Landlord for the purchase,
design and construction of the Building (including fees to SRM Associates for
time expended based on SRM Associates' standard billing rates), all accrued
interest thereon (at the rate of fifteen (15%) per annum) and payment of all
closing costs relating to such transfer.

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                  (c) OPTION TO EXTEND. Landlord hereby grants Tenant two (2)
options to extend the term of the Lease each for an additional period of five
(5) years, the first of which shall commence immediately after the expiration of
the initial term and, if the first option is properly exercised, the second of
which shall commence immediately after the expiration of the first option term,
upon the same term and conditions contained herein, except that (i) the Monthly
Base Rent for the Premises during an option term shall be equal to the then-fair
market rent for the Premises determined in the manner set forth in subparagraph
(A) below, (ii)Tenant shall accept the Premises at the commencement of an option
term in an "AS IS" condition without any obligation of Landlord to repaint,
remodel, repair, improve or alter the Premises; and (iii) there shall be no
further options to extend the term of the Lease.

                           (A) Tenant's election to exercise the first option to
extend as granted herein must be given to Landlord in writing no less than
twelve (12) months prior to expiration of the initial term and, if Tenant
properly exercises the first option, Tenant's election to exercise the second
option to extend as granted herein must be given to Landlord in writing no less
than twelve (12) months prior to the expiration of the first option term. If
Tenant properly exercises the option(s) as set forth herein, references in the
Lease to the term shall be deemed to include the applicable option term, unless
the context clearly provides otherwise. Notwithstanding anything to the contrary
contained herein, all option rights of Tenant pursuant to this Paragraph 2(c)
shall automatically terminate without notice and shall be of no further force
and effect, whether or not Tenant has timely exercised the option(s) as set
forth herein, if (i) an event of default (after applicable notice and cure
periods) exists at the time of exercise of an option or at the time of
commencement of the applicable option term or (ii) Landlord has given Tenant two
(2) or more notices respecting a default during the initial term of the Lease or
the first option term, as the case may be, whether or not the default is
subsequently cured, or (iii) Tenant has subleased fifty percent (50%) or more of
the Premises.

                           (B) If Tenant properly exercises an option to extend
the term of the Lease, Landlord and Tenant shall attempt in good faith to reach
agreement on the amount of Monthly Base Rent that will be applicable during the
option term. If Landlord and Tenant are unable to reach agreement as to the fair
market rent within thirty (30) days after Landlord's receipt of Tenant's notice
of exercise of Tenant's option to extend, then either party may demand an
appraisal by giving written notice to the other party, which demand must state
the name, address and qualifications of an appraiser selected by the party
demanding an appraisal (the "Notifying Party"). The fair market rent shall then
be determined as follows:

                           (1) Within ten (10) business days following the
Notifying Party's appraisal demand, the other party (the "Non-Notifying Party")
shall either approve the appraiser selected by the Notifying Party or select a
second properly qualified appraiser

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by giving written notice of the name and qualifications of such other appraiser
to the Notifying Party. If the Non-Notifying Party fails to select an appraiser
within such ten (10) business day period, then the Notifying Party's appraiser
shall be deemed selected by both parties and no other appraiser shall be
selected. If two appraisers are selected, such two appraisers shall select a
third qualified appraiser within ten (10) business days following selection of
the second appraiser. If the two appraisers fail to select a third qualified
appraiser, then the third shall be appointed by the then presiding judge of the
Superior Court of Alameda County upon application by either party.

                           (2) If only one appraiser is selected, then that
appraiser shall notify the parties in simple letter form of his/her
determination of the fair market rent within fifteen (15) business days
following his/her selection, which appraisal shall be conclusive and binding on
the parties as the fair market rent. If multiple appraisers are selected, they
shall meet not later than fifteen (15) business days following the selection of
the last appraiser. At such meeting, the appraisers shall attempt to determine
the fair market rent as of the termination date of the Lease by agreement of at
least two (2) of the appraisers. If two (2) or more of the appraisers agree on
the fair market rent at the initial meeting, such agreement shall be
determinative and binding upon the parties and the agreeing appraisers shall, in
simple letter form executed by the agreeing appraisers, forthwith notify both
Landlord and Tenant of the amount set by such agreement. If multiple appraisers
are selected and two (2) appraisers are unable to agree on the fair market rent,
then all appraisers shall submit to Landlord and Tenant an independent appraisal
of the fair market rent within twenty (20) business days following appointment
of the final appraiser. The parties shall then determine the fair market rent by
averaging the appraisals, provided that any high or loss appraisal, differing
from the middle by more than ten percent (10%) of the middle appraisal, shall be
disregarded.

                           (3) Fair market rent shall be determined without
taking into account the value of any alterations or improvements made to the
Premises or the Project work at Tenant's expense. All appraisers shall be
members of the American Institute of Real Estate Appraisers and shall have at
least five (5) years experience appraising properties comparable to, and in the
vicinity of, the Premises. If only one appraiser is selected, then each Party
shall pay one-half (1/2) of the fees of that appraiser. If three appraisers are
selected, each party shall bear the fee of the appraiser that it selected and
one-half (1/2) of the fees of the third appraiser.

                           (C) If the amount of the fair market rent is not
known as of the commencement of the applicable option term, then Tenant shall
continue to pay the Monthly Base Rent in effect at the expiration of the initial
term or the first option term, as the case may be, until the amount of the fair
market rent for the applicable option term is determined. When such
determination is made, Tenant shall pay any deficiency to Landlord, or Landlord
shall pay any overpayment to Tenant, as applicable, upon demand.

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         3.       RENT

                  (a) Tenant shall pay to Landlord as rental the amount
specified in the Basic Lease Information as the Monthly Base Rent. The first
Monthly Base Rent due under this Lease shall be payable by Tenant immediately
prior to term commencement and all subsequent Monthly Base Rent payments shall
be payable in advance on or before the first day of the first full calendar
month following commencement of the term and of each successive calendar month
thereafter during the term. If the term commences on other than the first day of
a calendar month, any excess payment of Monthly Base Rent shall be credited
against the next payment of Monthly Base Rent otherwise due.

                  (b) Effective as of each anniversary date of the Commencement
Date, the Monthly Base Rent shall be increased as indicated in the Basic Lease
Information.

                  (c) Tenant shall pay, as additional rent, all amounts of money
required to be paid to Landlord by Tenant hereunder in addition to monthly rent,
whether or not the same be designated "additional rent."

                  (d) Tenant hereby acknowledges that late payment by Tenant to
Landlord of rent and other amounts due hereunder will cause Landlord to incur
costs not contemplated by this Lease, the exact amount of which will be
extremely difficult to ascertain. Such costs include, but are not limited to,
processing and accounting charges, and late charges which may be imposed on
Landlord by the terms of any loan secured by the Building. Accordingly, if any
installment of rent or any other sums due from Tenant shall not be received by
Landlord within five (5) days after Landlord shall have given Tenant notice that
the some is past due, Tenant shall pay to Landlord a late charge equal to four
percent (4%) of such overdue amount. The parties hereby agree that such late
charge represents a fair and reasonable estimate of the costs Landlord will
incur by reason of late payment by Tenant. Acceptance of such late charge by
Landlord shall in no event constitute a waiver of Tenant's default with respect
to such overdue amount, nor prevent Landlord from exercising any of the other
rights and remedies under this Lease.

                  (e) Any amount payable by Tenant to Landlord, if not paid
within five (5) days of when due, shall bear interest from the date due until
paid at the rate of ten percent (10%) per annum or, if a higher rate is legally
permissible, at the highest rate legally permitted provided that interest shall
not be payable on late charges incurred by Tenant nor on any amounts upon which
late charges are paid by Tenant to the extent such interest would cause the
total interest to be in excess of that legally permitted. Payment of interest
shall not excuse or cure any default by Tenant under this Lease.

                  (f) All payments due from Tenant to Landlord hereunder shall
be made to Landlord without deduction or offset in lawful money of the United
States of America at the address for payment set forth in the Basic Lease
Information, or to such other

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person or at such other place as Landlord may from time to are designate by
notice to Tenant.

         4.       TAXES AND OPERATING EXPENSE

                  (a) Tenant shall pay directly or reimburse Landlord for all
Property Taxes assessed with respect to the Building during the term and all
Operating Expenses attributable to the Building during the term.

                  (b) For the purposes hereof, "Property Taxes" shall mean all
real property taxes, assessments or governmentally imposed few or charges (and
any tax or assessment levied wholly or partly in lieu thereof) levied, assessed,
or imposed, against the Building, including the tax parcel thereunder and the
portions of common area and appurtenances thereon or payable during the term.
Property Taxes shall also include the reasonable cost of protesting real
property taxes and assessments. Property Taxes shall not include and Tenant
shall not be required to pay any tax or assessment expense or any increase
therein (i) in excess of the amount which would be payable if such tax or
assessment expense were paid in installments over the longest possible term;
(ii) imposed on land and improvements other than the Building, (iii)
attributable to Landlord's inheritance, gift, transfer, estate or state taxes;
or (iv) resulting from the change of ownership or transfer of any interest in
the Premises or the Building during the initial Lease term.

                  (c) For the purposes hereof, "Operating Expenses" shall mean
the following expenses and costs of every kind and every nature which arise in
connection with the ownership and operation of the Building, including without
limitation: (i) all license, permit, and inspection fees; (ii) premiums and
deductibles for any insurance maintained with respect to the Building, (iii)
wages, salaries and related expenses and benefits of all on-site and off-site
employees engaged in Building operation, maintenance and security; (iv) all
supplies, materials, and equipment rental; (v) all maintenance, repair,
replacement, janitorial, security, and service costs; (vi) asset management fees
payable to Landlord on a monthly basis of one percent (1%) of Monthly Base Rent;
(vii) professional services fees; (viii) the cost of capital improvements to the
extent such capital improvements actually reduce other Operating Expenses or are
required by law, following the Commencement Date; provided, however, with
respect to capital items relating to the HVAC and roof membrane, such costs
shall be amortized over the useful life of the capital item in question; (ix)
all charges for heat, water, gas, electricity and other utilities used or
consumed in the Building; and (x) all other ordinary and necessary operating,
management and other expenses incurred in connection with the ownership and
operation of the Building including expenses in the nature of other Operating
Expenses which are payable with respect to the Building under declarations of
covenants, restriction, conditions and easements affecting the Building.

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                  (d) "Operating Expenses" shall not include and Tenant shall in
no event have any obligation to perform or to pay directly, or to reimburse
Landlord for, all or any portion of the following repairs, maintenance,
improvements, replacements, premiums, claim, loan fees, charges, costs and
expenses (collectively, "Costs"): (i) Costs occasioned by the act, omission or
violation of any Law by Landlord or its agents, employees or contractors; (ii)
Costs occasioned by fire, acts of God, or other casualties or by the exercise of
the power of eminent domain; (iii) Costs to correct any construction defect in
the Premises or the Building or to comply with any covenant, condition,
restriction, underwriter's requirement or law applicable to the Premises or the
Building on the Commencement Date; (iv) Costs incurred in connection with the
violation by Landlord of the terms and conditions of any lease or other
agreement; (v) Costs for pollution or flood insurance, insurance deductibles in
excess of $10,000 (excluding earthquake coverage), and co-insurance payments;
(vi) Costs incurred in connection with the presence of any Hazardous Material,
except to the extent caused by the release of the Hazardous Material in question
by Tenant; (vii) Costs in the nature of depreciation, amortization or other
expense reserves; (viii) Costs to repair, replace, restore or maintain the
structural portions of the Building including roof structure (but specifically
excluding roof membrane, exterior skin of Building, such as window glass and
tile facade, and Building HVAC, electrical, water, sewer and plumbing systems);
and (ix) compensation for any employee of Landlord or any compensation retained
by Landlord or its affiliates for management and administration of the Premises
or the Building in excess of the reasonable management fee which would be
charged by an unaffiliated professional management service for operation of
comparable projects in the vicinity. Tenant shall have the right to audit
Operating Expenses from time to time. If the results of such audit disclose that
Tenant has overpaid Operating Expenses by more than five percent (5%) of the
accurate amount of Operating Expenses payable by Tenant, then Landlord shall pay
the cost of such audit.

                  (e) Landlord shall deliver copies of all Property Tax bills
for the Building to Tenant within thirty (30) days of receipt thereof. At
Landlord's option, Tenant shall either (i) pay all such Property Tax bills
directly to the taxing authority and shall deliver evidence, acceptable to
Landlord of such payment(s) no later than ten (10) business days prior to the
applicable delinquency date(s) of such bills, or (ii) pay the amount of such
Property Tax bills directly to Landlord within thirty (30) days of delivery of
such copies to Tenant, for Landlord direct payment to the taxing authority.
Landlord shall have no obligation to pay any portion of the Property Taxes,
Tenant having assumed such obligation, and shall have no liability to Tenant or
otherwise for payment thereof. The foregoing notwithstanding, if Landlord's
first mortgage shall require periodic escrow payments on account of Property
Taxes or any part thereof, then Tenant shall be obligated to maim such payments
in installments, rather than bi-annually, on behalf of Landlord.

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                  (f) Tenant shall pay all Operating Expenses as and when such
payments may be required, except that the asset management fee payable to
Landlord under paragraph 4(c)(vi) shall be paid to Landlord each month at the
same time and in the same manner as monthly rent. Landlord shall have no
obligation to pay any portion of Operating Expenses, Tenant having assumed such
obligation, and shall have no liability to Tenant or otherwise for payment
thereof.

                  (g) This shall be a triple net Lease and Monthly Base Rent
shall be paid to Landlord absolutely net of all costs and expenses except as
specifically provided to the contrary in this Lease. The provisions for payment
of Operating Expenses and Property Taxes are intended to pass on to Tenant the
direct obligation to pay such costs and expenses and, by way of the asset
management fee payable under paragraph 4(c)(vi), to reimburse Landlord for its
management costs and expenses incurred in connection with Landlord's ownership
of the Building. Landlord and Tenant agree that the management, maintenance,
repair, preservation. replacement and operation of the Building, except for
defects in Landlord's Work or the Tenant Improvements and the structural
components of the Building including the roof structure (but specifically
excluding roof membrane, exterior skin of Building, such as window glass and
tile facade, and Building HVAC, electrical, water, sewer and plumbing systems)
are intended to be Tenant's sole responsibility during the term of this Lease.

         5. OTHER TAXES. Tenant shall pay or reimburse Landlord within thirty
(30) days following its demand for any taxes (other than local state or federal,
personal or corporate income taxes measured by the net income of Landlord from
all sources), assessments excises, levies, business taxes, gross receipts
business tax, license, permit, inspection, authorization, service payments in
lieu of taxes and any other few or charges of any kind, which are levied,
assessed, confirmed or imposed by any public authority: (a) upon, measured by or
reasonably attributable to the cost or value of Tenant's equipment, furniture,
fixtures and other personal property located in the Premises or leasehold
improvements made in or to the Premises at Tenant's expense; (b) upon or by
reason of Tenant's occupancy of the Premises or the parking facilities used by
Tenant in connection with the Premises; (c) imposed with respect to the rental
payable hereunder, or (d) upon this transaction.

         6.  USE.

                  (a) The Premises shall be used and occupied by Tenant for the
use set forth in the Basic Lease Information and for no other purpose without
Landlord's consent. Tenant shall, at Tenant's expense, comply promptly with all
applicable statutes, ordinances, rules, regulations, orders and requirements in
affect during the term regulating the particular use by Tenant of the Premises.
Specifically, Tenant shall comply with the City of Oakland zoning regulation
affecting the first twenty (20) feet of

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depth on the ground floor which requires a retail use. Tenant shall not use or
permit the use of the Premises in any manner that will tend to create waste or a
nuisance, nor shall Tenant, its employees, agents or invitees damage the
Premises or the Building, nor use any corridors, sidewalks or other areas
outside of the Premises for storage or any purpose other than access to the
Premises. Tenant shall not conduct any auction at the Premises. Notwithstanding
any other provision of this Lease, Tenant shall not use, keep or permit to be
used or kept on the Premises any foul or noxious gas or substance, nor shall
Tenant the or permit to be done anything in and about the Premises, either in
connection with activities hereunder expressly permitted or otherwise, which
would cause a cancellation of any policy of insurance maintained by Landlord in
connection with the Building or which would violate the terms of any covenants,
conditions or restrictions affecting the Building or the land on which it is
located.

                  (b) Tenant shall strictly comply with all statutes, laws,
ordinances, rules, regulations, and precautions now or hereafter mandated or
advised by any federal, state, local or other governmental agency with respect
to the use, generation, storage, or disposal of hazardous, toxic, or radioactive
materials (collectively, "Hazardous Materials"). As herein used, Hazardous
Materials shall include, but not be limited to, those materials identified in
Sections 66680 through 66685 of Title 22 of the California Code of Regulations,
Division 4, Chapter 30, as amended from time to time, and those substances
defined as "hazardous substances," hazardous materials, "hazardous wastes,"
"chemicals known to cause cancer or reproductive toxicity," "radioactive
materials," or other similar designations in the Comprehensive Environmental
Response Compensation and Liability Act of 1980, as amended, 42 U.S.C. Section
9601 et seq., the Resource Conservation and Recovery Act, 42 U.S.C. Section 6901
et seq., the Hazardous Materials Transportation Act, 49 U.S.C. Section 1801 et
seq., 33 U.S.C. Section 1251 et seq., 42 U.S.C. Section 300(f) et seq, 42 U.S.C.
7401 et seq, California Health and Safety Code Section 25249.5 et seq,
California Water Code Section 13000 et seq., California Health and Safety Code
Section 39000 et seq. and any other governmental statutes ordinances, rules,
regulations, and precautions adopted pursuant to the preceding laws or other
similar laws, regulations and guidelines now or hereafter in effect regulating
the environment Tenant shall not cause, or allow anyone else to cause any
Hazardous Materials to be used, generated, stored, or disposed of on or about
the Premises or the Building other than reasonable quantities of office and
cleaning supplies. Tenant will defend (with counsel approved by Landlord),
indemnify and hold Landlord, its members and its and their officers, directors,
employees and agents, any entity having a security interest in the Premises or
the Building, and its and their employees and agents (collectively,
"Indemnitees") harmless from and against all liabilities, claims, costs,
damages, and degradation of property value, including all foreseeable and
unforeseeable consequential damages, directly or indirectly arising out of the
release, use, generation , storage, or disposal of Hazardous Materials at the
Premises by Tenant or any person claiming under Tenant, including, without
limitation, the cost of any required or necessary investigation,

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monitoring, repair, cleanup, or detoxification and the preparation of any
closure or other required plans, whether such action is required or necessary
prior to or following the termination of this Lease, as well as penalties, fines
and claims for contribution to the full extent, that such action is
attributable, directly or indirectly, to the release, use, generation, storage,
or disposal of Hazardous Materials by Tenant or any person claiming under
Tenant. The consent by Landlord to the use, generation, storage, or disposal of
Hazardous Materials shall not excuse Tenant, from Tenant's obligation of
indemnification set forth above. Tenant's obligations under this paragraph 6
shall survive the expiration or termination of this Lease.

                  (c) To the best knowledge of Landlord and without further
independent investigation, (a) no Hazardous Material is present in the Premises
or at the Building or the soil, surface water or groundwater thereof, (b) no
underground storage tanks are present on the Premises or the Building, and (c)
no action, proceeding or claim is pending or threatened the Building or the
Premises concerning any Hazardous Material or pursuant to any Environmental Law.
Under no circumstance shall Tenant be liable for, and Landlord shall indemnify,
defend, protect and hold harmless Tenant, its agents, contractors, stockholders,
directors, successors, representatives, and assigns from and against, all
losses, costs, claims, liabilities and damages (including attorneys' and
consultants' fees) of every type and nature, directly or indirectly arising out
of or in connection with any Hazardous Material present at any time in, on or
about the Building, the Premises, or the soil, air, or surface water thereof, or
the violation of any Environmental Law, except to the extent that any of the
foregoing actually results from the release of Hazardous Material by Tenant or
Tenants agents in violation of applicable Environmental Laws.

         7. UTILITIES. Tenant shall directly pay for all water, sewer, gas,
electricity, heat, cooling, energy, telephone, refuse collection, alarm
monitoring services, and other utility-type services furnished to the Building,
together with all related installation or connection charges or deposits. Tenant
shall have access to the Premises and Building twenty-four hours a day, seven
days a week. Inasmuch as Tenant shall have the sole obligation to obtain provide
and maintain any such services during the term Tenant agrees that Landlord shall
not be in breach of this Lease nor be liable to Tenant for damages or otherwise,
to the extent there is any failure to furnish, or a delay in furnishing any such
service, or a change in the quantity or character of any such service during the
term.

         8. MAINTENANCE, REPAIRS AND ALTERATIONS.

                  (a) Landlord shall, at Landlord's sole expense, keep in good
condition and repair and maintain the foundations, exterior walls, roof, and all
structural components including the roof structure (but specifically excluding
roof membrane,

                                       10
<PAGE>

exterior skin of Building, such as window glass and tile facade, and Building
HVAC, electrical, water, sewer and plumbing system) of the Building. Landlord
shall perform and construct, and Tenant shall have no responsibility to perform
or construct, any repair, maintenance or improvements (a) necessitated by the
acts or omissions of Landlord, or its respective agents, employees, contractors
or invitees, (b) occasioned by fire, acts of God or other casualty or by the
exercise of the power of eminent domain, and (c) required as a consequence of
any violation of any Laws or construction defects in the Tenant Improvements or
the Landlord's Work as of the Commencement Date. In performing all repair and
maintenance, Landlord shall use its best efforts to minimize any disruption to
Tenant.

                  (b) Subject to Landlord's repair and maintenance obligations
as set forth above, Tenant shall, at Tenant's sole expense, keep in good
condition and repair and maintain the Building and Premises including, but not
limited to, the exterior of the Building, such as window glass and tile facade,
all HVAC, electrical, water, sewer and plumbing systems, plumbing and electrical
fixtures and outlets, and all computer and telecommunications; wiring and
outlets. If an event of default shall exist (after applicable notice and cure
periods) due to Tenant's failure to the so, Landlord may, but shall not be
required to, enter the Premises and put them in good condition, and Landlord's
costs thereof as set forth in Landlord's demand to Tenant shall automatically
become due and payable as additional rent.

                  (c) Tenant shall not, without Landlord's prior consent, make
any alterations, improvements or additions in or about the Premises ("Tenant
Additions"), except for non-structural alterations or improvements not exceeding
$25,000 in any one instance. As a condition to giving such consent, Landlord may
require that Tenant remove any such Tenant Additions at the expiration of the
term, and to restore the Premises to their prior condition. Before commencing
any work relating to Tenant Additions, Tenant shall notify Landlord of the
expected date of commencement thereof and of the anticipated cost thereof, and
(if Landlord's consent is required) shall furnish complete drawings and
specifications describing such work as well as such information as shall
reasonably be requested by Landlord substantiating Tenant's ability to pay for
such work. Tenant shall give Landlord at least five (5) business days' notice
prior to commencing any such work and Landlord shall then have the right at any
time and from time to time to post and maintain on the Premises such notices as
Landlord reasonably deems necessary to protect the Premises, the Building and
Landlord from mechanics' liens or any other liens. In any event, Tenant shall
pay when due all claim for labor or materials furnished to or for Tenant at or,
for use in the Premises. Tenant shall not permit any mechanics' liens to be
levied against the Premises for any labor or materials furnished to Tenant or
claimed to have been furnished to Tenant or to Tenant's agents or contractors in
connection with work performed or claimed to have been performed on the Premises
by or at the direction of Tenant. All Tenant Additions in or about the Premises

                                       11
<PAGE>

performed by or on behalf of Tenant shall be done by contractors designated or
approved by Landlord, in a good, workmanlike manner which does not disturb or
interfere with other tenants and is in compliance with all applicable laws,
ordinances, regulations and orders of any authority having jurisdiction
thereover, as well as the requirements of insurers of the Premises and the
Building. Prior to commencing any such work, if required by Landlord, Tenant
shall purchase builder's risk insurance in an amount no less than the value of
the completed work of alteration, addition or improvement on an all-risk basis,
covering all perils then customarily covered by such insurance. In addition,
prior to the commencement of any such work costing more than $100,000, if
Landlord so requests, Tenant shall furnish to Landlord performance and payments
bonds in a form and issued by a surety reasonably acceptable to Landlord in an
amount equal to the cost of such work of alteration, improvement or addition.
Notwithstanding anything in this paragraph 8 to the contrary, upon Landlord's
request, Tenant shall remove any contractor, or material supplier from the
Premises and the Building if the work or presence of such person or entity
results in labor disputes in or about the Building or damage to the Premises or
the Building. Upon completion of work performed for Tenant, at Landlord's
request Tenant shall deliver to Landlord evidence of full payment therefor and
full and unconditional waivers and releases of liens for all labor, services
and/or materials used. Unless Landlord requires their removal, as set forth
above, all Tenant Additions which may be made on the Premises shall, at
Landlord's option, become the property of Landlord and remain upon and be
surrendered with the Premises at the termination or expiration of the term;
provided, however, that Tenant's machinery, equipment and trade fixtures, other
than any which may be affixed to the Premises so that they cannot be removed
without material damage to the Premises, shall remain the property of Tenant and
shall. be removed by Tenant on or before such time.

                  (d) Tenant Additions and Tenant's trade fixtures, furniture,
equipment and other personal property installed in the Premises ("Tenant's
Property") shall at all times be and remain Tenant's property. Except for Tenant
Additions which cannot be removed without structural injury to the Premises, at
any time Tenant may remove Tenant's Property from the Premises, provided that
Tenant repairs all damage caused by such removal. Landlord shall have no right
to require Tenant to remove any Tenant Additions unless it notifies Tenant at
the time it consents to such Tenant Additions that it shall require such Tenant
Additions to be removed. Landlord shall have no security interest or lien on any
item of Tenant's Property. Within ten (10) days following Tenant's request,
Landlord shall execute documents reasonably acceptable to Tenant to evidence
Tenant waiver of any right, title, lien or interest in Tenant's Property and
giving any lenders holding a security interest or lien on Tenant's Property
reasonable rights of access to the Premises to remove such Tenant's Property,
provided that such lenders repair any damage caused by such removal and such
lender agrees to remove Tenant's Property within ten (10) days of notice by
Landlord.

                                       12
<PAGE>

         9.       INSURANCE.

                  (a) Tenant shall obtain and maintain during the term of this
Lease commercial general liability insurance with a combined single limit for
personal injury and property damage in an amount not less than $3,000,000, and
employees liability and workers' compensation insurance as required by law.
Tenant's commercial general liability insurance policy shall (i) include
coverage for premises and operations liability, products and completed
operations liability, broad form property damage, blanket contractual liability
and personal and advertising liability, (ii) provide that the insurer has the
duty to defend all insureds, and (iii) provide that defense costs do not deplete
policy limits. Such insurance shall also be endorsed to provide that (1) it may
not be canceled or altered in such a manner as adversely to affect the coverage
afforded thereby without 30 days' prior written notice to Landlord, (2) Landlord
and other entities designated by Landlord are named as additional insureds, (3)
the insurer acknowledges acceptance of the mutual waiver of claim by Landlord
and Tenant pursuant to subparagraph (b) below, and (4) such insurance is primary
with respect to Landlord and that any other insurance maintained by Landlord is
excess and noncontributing with such insurance. If, in the opinion of Landlord's
insurance adviser, based on a substantial increase in recovered liability claim
generally, the specified amounts of coverage are no longer adequate, within 30
days following Landlord's request, such coverage shall be appropriately
increased. Tenant shall also obtain and maintain insurance ("Personal Property
Insurance") covering leasehold improvements paid for by Tenant and Tenant's
personal property and fixtures from time to time in, on, or at the Premises, in
an amount not less than one hundred percent (100%) of the full replacement cost,
without deduction for depreciation, providing protection against events
protected under "All Risk Coverage," as well as against sprinkler damage,
vandalism, and malicious mischief. Any proceeds from the Personal Property
Insurance shall be used for the repair or replacement of the property damaged or
destroyed, unless this Lease is terminated under an applicable provision herein.
Tenant shall obtain and maintain business interruption insurance in an amount
not less than the greater of Tenant's annual gross revenue or an amount adequate
to provide for payment of Monthly Base Rent and other amounts due Landlord under
this Lease during a one year interruption of Tenant's business by fire or other
casualty. Prior to the commencement of the term Tenant shall deliver to Landlord
duplicates of such policies or certificates thereof with endorsements, and at
least thirty (30) days prior to the expiration of such policy or any renewal
thereof, Tenant shall deliver to Landlord replacement or renewal binders,
followed by duplicate policies or certificates within a reasonable time
thereafter. If Tenant fails to obtain such insurance or to furnish Landlord any
such duplicate policies or certificates as herein required, Landlord may, at its
election, upon notice to Tenant, procure and maintain such coverage and Tenant
shall reimburse Landlord on demand as additional rent for any premium so paid by
Landlord. Tenant shall have the right to provide all insurance coverage required
herein to be

                                       13
<PAGE>

provided by Tenant pursuant to blanket policies so long as such coverage is
expressly afforded by such policies.

                  (b) Landlord shall maintain in effect during the term of this
Lease, and Tenant shall reimburse as an Operating Expense, "all risk" property
insurance insuring against risk of loss or damage to the Building and the
Premises for the full replacement cost thereof against all risk of physical
loss, including but not limited to perils included within the classification of
fire, extended coverage, vandalism, malicious mischief, earthquake, flood (if
the same is required by a lender having a lien on the Building). Landlord shall
also maintain in effect during the term of this Lease, and Tenant shall
reimburse as an Operating Expense, a policy of rental value or rent loss
insurance covering a period of at last one (1) year, with loss payable to
Landlord. Notwithstanding anything in the Lease to the contrary, Landlord and
Tenant hereby release each other and their respective agents, employees,
successors, assignees and subleases from all liability for injury to any person
or damage to any property that is caused by or results from a risk which is
actually insured against, which is required to be insured against under the
Lease, or which would normally be covered by "all risk" property insurance,
without regard to the negligence or willful misconduct of the person or entity
so released. All of Landlord's and Tenant's repair and indemnity obligations
under the Lease shall be subject to the waiver and release contained in this
paragraph. Each party shall cause each insurance policy it obtains to provide
that the insurer thereunder waives all recovery by way of subrogation as
required herein in connection with any injury or damage covered by such policy.

                  (c) Landlord hereby waives all claims against Tenant, and
Tenant's partners and its and their officers, directors, partners, employees,
agents and representatives (collectively, "Tenant's Parties") for loss or damage
to the extent that such loss or damage is insured against under any valid and
collectable insurance policy insuring Landlord or would have been insured
against but for any deductible amount under any such policy, and Tenant waives
all claims against Landlord including Landlord's partner and its and their
officers, directors, partners, employees, agents and representatives
(collectively, "Landlord's Parties") for loss or damage to the extent such loss
or damage is insured against under any valid and collectable insurance policy
insuring Tenant or required to be maintained by Tenant under this Lease or would
have been insured against but for any deductible amount under any such policy.

         10. INDEMNIFICATION. Tenant shall hold harmless, indemnify and defend
Landlord against all claims, damages, losses, liabilities and expenses (except
such as arises, from the negligence or willful misconduct of Landlord, its
agents, employees or contractors or from latent defects in the Tenant
Improvements or Landlord's Work or Landlord's breach of this Lease) (i) for
damage to any property or injury to or death of any person arising from the
breach of this Lease by Tenant, or (ii) arising from the

                                       14
<PAGE>

negligence or willful misconduct of Tenant, its employees, agents, or
contractors. The foregoing indemnity obligation of Tenant shall include
reasonable attorneys' fees, investigation costs, and all other reasonable costs
and expenses incurred by Landlord from the first notice that any claim or demand
is to be made or may be made. Landlord shall indemnify, defend (with counsel
reasonably satisfactory to Tenant), protect and hold harmless Tenant and its
agents, employees and contractors from and against all losses costs, claims,
liabilities and damages (including reasonable attorneys' fees) arising from the
negligence or willful misconduct of Landlord, its employees, agents or
contractors, or from Landlord's breach of this Lease. The provisions of this
paragraph 10 shall survive the termination of this Lease with respect to any
damage, injury, or death occurring prior to such termination.

         11.      DAMAGE OR DESTRUCTION.

                  (a) If during the term the Premises are totally or partially
destroyed, or any other portion of the Building is damaged in such a way that
Tenant's use of the Premises is materially interfered with, from a risk which is
wholly covered by insurance proceeds made available to Landlord for such
purpose, Landlord shall proceed with reasonable diligence to repair the damage
or destruction and this Lease shall not be terminated; provided, however, that
if in the opinion of Landlord's architect or contractor the work of repair
cannot be completed in ninety (90) days following such damage or destruction,
Landlord may at its election terminate this Lease by notice given to Tenant
within thirty (30) days following the event or such longer period as may
reasonably be necessary to obtain information from its architect or contractor.

                  (b) If during the term the Premises are totally or partially
destroyed, or any other portion of the Building is damaged in such a way that
Tenant's use of the Premises is materially interfered with, from a risk which is
not wholly covered by insurance proceeds made available to Landlord for repair
or reconstruction, Landlord may at its election by notice to Tenant given within
thirty (30) days following the event or such longer period as may reasonably be
necessary for Landlord to obtain information from its architect or contractor,
either restore the Premises or terminate this Lease.

                  (c) The foregoing notwithstanding if (i) during the term the
Premises are totally or partially destroyed, or any other portion of the
Building is damaged in such a way that Tenant's use of the Premises is
materially interfered with, and (ii) in the opinion of Landlord's architect or
contractor the work of repair cannot be completed within one (1) year following
such damage or destruction, then Tenant may at its election terminate this Lease
by notice given to Landlord within thirty (30) days following the event or such
longer period as may reasonably be necessary to obtain information from
Landlord's architect or contractor verifying the estimated repair period.

                                       15
<PAGE>

                  (d) In case of destruction or which materially interferes,
with Tenant's use of the Premises, if this Lease is not terminated as above
provided, rent shall be abated during the period required for the work of repair
based upon the degree of interference with Tenant's use of the Premises. Except
for abatement of rent, Tenant shall have no claim against Landlord for any loss
suffered by Tenant due to damage or destruction of the Premises or any work of
undertaken as herein provided. Tenant expressly waives the provisions of
applicable law which would otherwise provide for termination of a hiring upon
destruction of the thing hired, which are superseded by this paragraph 11.

         12.      EMINENT DOMAIN.

                  If all or any part of the Premises shall be taken as a result
of the exercise of the power of eminent domain or sold by Landlord under threat
thereof, this Lease shall terminate as to the part so taken as of the date of
taking or sale and, in the case of a partial taking, Tenant shall have the right
to terminate this Lease as to the balance of the Premises by notice to the other
within thirty (30) days after such date if the portion of the Premises taken
shall be of such extent and nature as substantially to handicap, impede or
impair Tenant's use of the balance of the Premises, or render the balance of the
Premises inadequate for Tenant's purposes. In the event of any taking or such
sale, Landlord shall be entitled to any and all compensation, damages, income,
rent, awards, or any interest therein whatsoever which may be paid or made in
connection therewith, and Tenant shall have no claim against Landlord for the
value of any unexpired term of this Lease as or otherwise; provided, however,
Tenant may make an independent claim for Tenant's relocation costs, the
unamortized value of any alterations or improvements made to the Premises or
Building at Tenant's expense, and the "bonus value" of the Lease (i.e., the
difference between Monthly Base Rent payable hereunder and the then fair market
rental value of the Premises) for the balance of the Lease term so long as
Tenant's award, if any, does not diminish Landlord's award. In the event of a
partial taking of the Premises which does not result in a termination of this
Lease, the monthly rental thereafter to be paid shall be equitably reduced on a
pro rata basis based upon relative area.

         13.      ASSIGNMENT AND SUBLETTING.

                  (a) Tenant shall not assign this Lease or any interest herein
or sublet the Premises or any part thereof, either directly or by operation of
law, without the prior consent of Landlord, which consent shall not be
unreasonably withheld. Tenant shall not hypothecate this Lease or any interest
herein without the prior consent of Landlord, which consent may be withheld by
Landlord in its absolute discretion. Any of the foregoing acts without such
consent shall be void. In connection with each consent requested by Tenant,
Tenant shall submit to Landlord the terms of the proposed transaction, the
identity of the parties to the transaction, the proposed documentation for the
transaction, current financial statements of any proposed assignee or sublessee
and all

                                       16
<PAGE>

other information reasonably requested by Landlord concerning the proposed
transaction and the parties involved therein. In the case of any assignment or
subletting, the proposed assignee or sublessee shall agree in writing to perform
for the benefit of Landlord all of the Tenant's obligations under this Lease or
so much thereof as are allocable to any portion of the Premises proposed to be
sublet.

                  (b) Without limiting the other instances in which it may be
reasonable for Landlord to withhold its consent to an assignment or subletting,
Landlord and Tenant acknowledge that it shall be reasonable for Landlord to
withhold its consent in the following instances:

                           (1) the proposed assignee or sublessee is a
governmental agency,

                           (2) in Landlord's reasonable judgment, the use of the
Premises would violate this Lease;

                           (3) in Landlord's reasonable judgment, the financial
worth of the proposed assignee or sublessee would be insufficient to perform its
obligations under this Lease;

                           (4) Landlord has experienced previous defaults by or
is in litigation with the proposed assignee or subtenant;

                           (5) the use of the Premises by the proposed assignee
or subtenant will violate any applicable law, ordinance or regulation;

                  (c) If Tenant proposes to assign this Lease, Landlord may, by
notice given within thirty (30) days of Tenant's notice, elect to terminate this
Lease as of the date of the proposed assignment. If Landlord so terminates this
Lease, Landlord may, if it elects, enter into a new lease covering the Premises
with the intended assignee on such terms as Landlord and such person may agree,
or enter into a new lease covering the Premises or a portion thereof with any
other person; in such event, Tenant shall not be entitled to any portion of the
profit, if any, which Landlord may realize on account of such termination and
reletting. Landlord's exercise of its aforesaid option shall not be construed to
impose any liability upon Landlord with respect to any real estate brokerage
commission(s) or any other costs or expenses incurred by Tenant in connection
with its proposed assignment. If Landlord does not exercise its option to
terminate this Lease, Tenant shall be free to assign this Lease, subject to
obtaining Landlord's prior consent as hereinabove provided.

                  (d) As used in this paragraph 13, the term "assign" or
"assignment" shall include, without limitation, any sale, transfer or other
disposition of all or any

                                       17
<PAGE>

portion of Tenant's estate under this Lease, whether voluntary or involuntary,
and whether by operation of law or otherwise including any of the following:

                           (1) If Tenant is a corporation or a limited liability
company: (i) any dissolution, merger, consolidation or other reorganization of
Tenant, or (ii) a sale of more than fifty percent (50%) of the value of the
assets of Tenant, or (iii) if Tenant is a corporation or limited liability
company with fewer than 500 shareholders, sale or other transfer of a
controlling percentage of the capital stock of or membership interests in
Tenant. The phrase "controlling percentage' means the ownership of, and the
right to vote, stock or membership interests possessing at least fifty percent
(50%) of the total combined voting power of all classes of Tenant's stock or
membership interests issued, outstanding and permitted to vote for the election
of directors;

                           (2) If Tenant is a trust, the transfer of more than
fifty percent (50%) of the beneficial interest of Tenant, or the dissolution of
the trust;

                           (3) If Tenant is a partnership or joint venture, the
withdrawal, or the transfer of the interest of any general partner or joint
venturer or the dissolution of the partnership or joint venture; or

                           (4) If Tenant is composed of tenants-in-common, the
transfer of interest of any co-tenants, or the partition or dissolution of the
co-tenancy.

The foregoing notwithstanding, Tenant may, without Landlord's prior written
consent and without payment of any amount to Landlord, sublet any of the
Premises or assign any interest in the Lease to (a) a subsidiary, affiliate,
division or corporation controlling, controlled by or under common control with
Tenant, (b) a successor corporation related to Tenant by merger, consolidation,
nonbankruptcy reorganization, or government action, or (c) a purchase of
substantially all of Tenant's assets located at the Premises. Neither the sale
or transfer of Tenant's capital stock, including, without limitation, a transfer
in connection with the merger, consolidation or nonbankruptcy reorganization of
Tenant and any sale through any private or public offering, nor the pledge of or
grant of a security interest in any of the Tenant's capital stock, shall be
deemed an assignment, subletting or other transfer of the Lease or the Premises.

                  (e) No sublessee shall have a right further to sublet, and any
assignment by a sublessee of its sublease shall be subject to Landlord's prior
consent in the same manner as if Tenant were entering into a new sublease.

                  (f) In the case of an assignment, one-half (1/2) of all sums
or other economic consideration received by Tenant as compensation for such
assignment shall be paid to Landlord after first deducting the cost of any real
commissions incurred in

                                       18
<PAGE>

connection with such assignment and the unamortized value of all Tenant
Additions and improvements to the Premises paid for by Tenant.

                  (g) In the case of a subletting, all sums or economic
consideration received by Tenant as a result of such subletting may be retained
by Tenant.

                  (h) Regardless of Landlord's consent, no subletting or
assignment shall release Tenant of Tenant's obligations or alter the primary
liability of Tenant to pay the rental and to perform all other obligations to be
performed by Tenant hereunder. The acceptance of rental by Landlord from any
other person shall not be deemed to be a waiver by Landlord of any provision
hereof. Consent to one assignment or subletting shall not be deemed consent to
any subsequent assignment or subletting. In the event of default by any assignee
of Tenant or any successor of Tenant in the performance of any of the terms
hereof, Landlord may proceed directly against Tenant without the necessity of
exhausting remedies against such assignee or successor. Landlord may consent to
subsequent assignments or subletting of this Lease or amendments or
modifications to this Lease with assignees of Tenant, without notifying Tenant,
or any successor of Tenant, and without obtaining its or their consent thereto
and such action shall not relieve Tenant of liability under this Lease.

                  (i) If Tenant shall assign or sublet the Premises or request
the consent of Landlord to any assignment or subletting or if Tenant shall
request the consent of Landlord for any act that Tenant proposes to do, then
Tenant shall pay Landlord's reasonable attorneys' fees incurred in connection
therewith, not to exceed $1,500.

                  (j) The voluntary or other surrender of this Lease by Tenant,
the mutual cancellation thereof or the termination of this Lease by Landlord as
a result of Tenant's default shall, at the option of Landlord, terminate all or
any existing subtenancies or may, at the option of Landlord, operate as an
assignment to Landlord of any or all of such subtenancies.

         14.      DEFAULT BY TENANT.

                  (a) Any of the following events shall constitute events of
default under this Lease:

                           (1) Tenant's failure to pay any rent or other sum
payable hereunder within five (5) days after Landlord has given Tenant notice of
nonpayment;

                           (2) Tenant's failure to perform any of the other
terms, covenants, agreements or conditions contained herein and the continuation
of such default for a period of thirty (30) days after notice by Landlord or
beyond the time reasonably

                                       19
<PAGE>

necessary for cure if the default is of the nature to require more than thirty
(30) days to remedy, but in any event within sixty (60) days following
Landlord's notice;

                           (3) the bankruptcy or insolvency of Tenant, any
transfer by Tenant in fraud of creditors, assignment by Tenant for the benefit
of creditors, or the commencement of any proceedings of any kind by or against
Tenant under any provision of the Federal Bankruptcy Act or under any other
insolvency, bankruptcy or reorganization act; the appointment of a receiver for
a substantial part of the assets of Tenant; or the levy upon this Lease or any
estate of Tenant hereunder by any attachment or execution; unless, in the event
any such proceedings are involuntary, Tenant is discharged from the same within
sixty (60) days thereafter; or

                           (4) the abandonment of the Premises.

                  (b) Upon the occurrence of any event of default by Tenant
hereunder, Landlord may, at its option and without any further notice or demand,
in addition to any other rights and remedies given hereunder or by law, do any
of the following:

                           (1) Landlord shall have the right so long as such
default continues, to give notice of termination to Tenant, and on the date
specified in such notice this Lease shall terminate.

                           (2) In the event of any such termination of this
Lease, Landlord may then or at any time thereafter, reenter the Premises and
remove therefrom all persons and property and again repossess and enjoy the
Premises, without prejudice to any other remedies that Landlord may have by
reason of Tenant's default or of such termination.

                           (3) In the event of any such termination of this
Lease, and in addition to any other rights and remedies Landlord may have,
Landlord shall have all of the rights and remedies of a Landlord provided by
Section 1951.2 of the California Civil Code. The amount of damages which
Landlord may recover in event of such termination shall include, without
limitation, (i) the worth at the time of award (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) of the amount by which the unpaid rent for
balance of the term after the time of award exceeds the amount of rental loss
that Tenant proves could be reasonably avoided, (ii) all legal expenses and
other related costs incurred by Landlord following Tenant's default, (iii) all
costs incurred by Landlord in restoring the Premises to good order and
condition, or in remodeling, renovating or otherwise preparing the Premises for
reletting, and (iv) all costs (including, without limitation, any brokerage
commissions) incurred by Landlord in-reletting the Premises, to the extent
allocable to the remaining term of this Lease.

                                       20
<PAGE>

                           (4) Landlord shall also have the remedy described in
California Civil Code Section 1951.4 (lessor may continue the lease in effect
after lessee's breach and abandonment and recover rent as it becomes due, if
lessee has right to sublet or assign, subject only to reasonable limitations).

                           (5) For the purpose of determining the unpaid rent in
the event of a termination of this Lease, or the rent due hereunder in the event
of a reletting of the Premises, the monthly rent reserved in this Lease shall be
deemed to be the sum of the rental due under paragraph 3 above and the amounts
last payable by Tenant pursuant to paragraph 4 above and any "free rent" or rent
waived or abated by Landlord as an inducement for Tenant to enter into this
Lease.

                           (6) Landlord's acceptance of payment from Tenant of
less than the amount of rent then due shall not constitute a waiver of any
rights of Landlord or Tenant including, without limitation, any right of
Landlord to recover possession of the Premises.

                           (7) After terminating this Lease, Landlord may remove
any and all personal property located in the Premises and place such property in
a public or private warehouse or elsewhere at the sole cost and expense of
Tenant.

                  (c) Even though Tenant has breached this Lease to and
abandoned the Premises, this Lease shall continue in effect for so long as
Landlord does not terminate Tenant's right to possession, and Landlord may
enforce all its rights and remedies under this Lease, including the right to
recover rental as it becomes due under this Lease. Acts of maintenance or
preservation, efforts to relet the Premises, or the appointment of a receiver
upon initiative of Landlord to protect Landlord's interest under this Lease
shall not constitute a termination of Tenant's right to possession.

                  (d) Landlord and Tenant hereby waive trial by jury in any
action, proceeding or counterclaim brought by either of the parties hereby
against the other on any matter not relating to personal injury or property
damage but otherwise arising out of or in any way connected with this Lease,
Tenant's use or occupancy of the Premises, and any statutory remedy.

                  (e) The remedies provided for in this Lease are in addition to
any other remedies available to Landlord at law or in equity, by statute or
otherwise.

         15. LANDLORD'S RIGHT TO CURE DEFAULT. If Tenant shall fail to pay any
sum of money, other than rental, required to be paid by it hereunder or shall
fail to perform any other act on its part to be performed hereunder and such
failure shall continue for thirty (30) days after notice thereof by Landlord,
Landlord may, but shall not be obligated so to do, and without waiving or
releasing Tenant from any obligations of Tenant, make any

                                       21
<PAGE>

such payment or perform any such other act on Tenant's part to be made or
performed as in this Lease provided. All sums so paid by Landlord and all
necessary incidental costs shall be deemed additional rent hereunder, and shall
be payable to Landlord on demand and Landlord shall have (in addition to any
other right or remedy of Landlord) the same rights and remedies in the event of
the nonpayment thereof by Tenant as in the case of default by Tenant in the
payment of rental.

         16. DEFAULT BY LANDLORD. Landlord shall not be in default under this
Lease unless Landlord fails to perform obligations required of Landlord
hereunder within a reasonable time, but in no event later than thirty (30) days
after notice by Tenant to Landlord specifying wherein Landlord has failed to
perform such obligation; provided, however, that if the nature of Landlord's
obligation is such that more than thirty (30) days are required for performance,
then Landlord shall not be in default if Landlord commences performance within
such 30-day period and thereafter diligently prosecutes the same to completion.

         17.      LETTER OF CREDIT.

                  (a) In lieu of depositing a cash security deposit with
Landlord, Tenant shall, on execution of this Lease, deliver to Landlord and
cause to be in effect during the Lease Term an unconditional, irrevocable letter
of credit ("LOC") in the amount specified as the LOC amount in the Basic Lease
Information, (the "LOC Amount"). The LOC shall have an initial term of five (5)
year and shall thereafter renew automatically from year to year. The LOC shall
be in a form reasonably acceptable to Landlord and shall be issued by an LOC
bank selected by Tenant and reasonably acceptable to Landlord. An "LOC bank" is
a bank that accepts deposits, maintains accounts, has a local office that will
negotiate a letter of credit, and the deposits of which are insured by the
Federal Deposit Insurance Corporation. Tenant shall pay all expenses, points, or
fees incurred by Tenant in obtaining the LOC. The LOC shall not be mortgaged,
assigned or encumbered in any manner whatsoever by Tenant without the prior
written consent of Landlord. Tenant acknowledges that Landlord has the right to
transfer or mortgage its interest in 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 LOC and/or the LOC Security Deposit (as
defined below) to the transferee or mortgagee, and, in the event of such
transfer, Tenant shall took solely to such transferee or mortgagee for the
return of the LOC and/or the LOC Security Deposit.

                  (b) Tenant may, from time to time, replace any existing LOC
with a new LOC if the new LOC (a) becomes effective at least thirty (30) days
before expiration of the LOC that it replaces; (b) is in the required LOC
amount; (c) is issued by an LOC bank acceptable to Landlord, and (d) otherwise
complies with the requirements of this paragraph.

                                       22
<PAGE>

                  (c) Landlord shall hold the LOC as security for the
performance of Tenant's obligations under this Lease. If, after notice and
failure to cure within any applicable period provided in this Lease, Tenant
defaults on any provision of this Lease , Landlord may, without prejudice to any
other remedy it has, draw on that portion of the LOC necessary to (a) pay
Monthly Base Rent or other sum in default; (b) pay or reimburse Landlord for any
amount that Landlord may spend or become obligated to send in exercising
Landlord's rights under paragraph 15; and/or (c) compensate Landlord for any
expense, loss or damage that Landlord may suffer because of Tenant's default. If
Tenant fails to renew or replace the LOC at least thirty (30) days before its
expiration, Landlord may, without prejudice to any other remedy it has, draw on
the entire amount of the LOC. Tenant shall thereafter have the right, however,
to deliver to Landlord a replacement LOC complying with the term of this
paragraph 17, whereupon Landlord shall return the LOC Security Deposit, less any
amounts otherwise credited pursuant to the terms hereof, to Tenant.

                  (d) Any amount of the LOC that is drawn on by Landlord but not
applied by Landlord shall be held by Landlord as a security deposit (the "LOC
Security Deposit") in accordance with this paragraph. The LOC Security Deposit
shall be held by Landlord as security for the performance by Tenant of all of
the provisions of this Lease. Landlord shall not be required to keep the LOC
Security Deposit separate from its general accounts.

                  (e) If Landlord draws on any portion of the LOC and/or applies
all or any portion of such draw, Tenant shall, within ten (10) business days
after demand by Landlord, either (i) deposit cash with Landlord in an amount
that, when added to the amount remaining under the LOC and the amount of any LOC
Security Deposit, shall equal the LOC Amount then required under this paragraph;
or (ii) reinstate the LOC to the full LOC Amount.

                  (f) If Tenant performs all of Tenant's obligations hereunder,
the LOC Security Deposit, or so much thereof as has not theretofore been applied
by Landlord, shall be returned, without payment of interest for its use, to
Tenant (or, at Landlord's option, to the last assignee, if any, of Tenant's
interest hereunder) at the expiration of the term hereof, and after Tenant has
vacated the Premises. No trust relationship is created herein between Landlord
and Tenant with respect to the LOC Security Deposit.

         18.      ESTOPPEL CERTIFICATE.

                  (a) Tenant shall at any time within ten (10) business days
following request from Landlord execute, acknowledge and deliver to Landlord a
statement certifying (1) that this Lease is unmodified and in full force and
effect (or, if modified, stating the nature of such modification and certifying
that this Lease, as so modified, is in full force and effect), (2) the date to
which the rent and other sums payable hereunder

                                       23
<PAGE>

have been paid, (3) acknowledge that there are not, to Tenant's knowledge, any
uncured defaults on the part of Landlord hereunder, or specifying such defaults,
if any, which are claimed and (4) such other matters as may reasonably be
requested by Landlord. Any such statement may be conclusively relied upon by any
prospective purchaser or encumbrancer of the Building.

                  (b) Tenant's failure to deliver such statement within such
time shall be deemed Tenant's confirmation that: (1) this Lease is in full force
and effect, without modification except as may be represented by Landlord, (2)
there are no uncured defaults in Landlord's performance, and (3) not more than
one (1) month's rent has been paid in advance.

                  (c) If Landlord desires to sell, finance or refinance the
Building within ten (10) business days of Landlord's request, Tenant shall
deliver to any lender designated by Landlord such financial statements of Tenant
as may be reasonably required by such lender. All such financial statements
shall be received by Landlord in confidence and shall be used for the purposes
herein set forth.

         19.      SUBORDINATION, AMENDMENT FOR LENDER.

                  (a) This Lease, at Landlord's option, shall be subordinate to
any ground lease, mortgage, deed of trust or any other hypothecation for
security now or hereafter placed upon the Building and to any and all advances
made on the security thereof and to all renewals, modifications, consolidations,
and extensions thereof. Notwithstanding such subordination, Tenant's right to
quiet possession of the Premises shall not be disturbed if an event of default
by Tenant does not then exist (beyond applicable notice and cure periods),
unless this Lease is otherwise terminated pursuant to its terms. If any
mortgagee, beneficiary, trustee or ground lessor shall elect to have this Lease
prior to the lien of its mortgage, deed of trust or ground lease, and shall give
notice thereof to Tenant, this Lease shall be deemed prior to such mortgage,
deed of trust, or ground lease, whether this Lease as is dated prior to or
subsequent to the date of said mortgage, deed of trust or ground lease or the
date of recording thereof. If any mortgage or deed of trust to which this Lease
is subordinate is foreclosed or a deed in lieu of foreclosure is given to the
mortgagee or beneficiary, Tenant shall attorn to the purchaser at the
foreclosure sale or to the grantee under the deed in lieu of foreclosure; if any
ground lease to which this Lease is subordinate is terminated, Tenant shall
attorn to the ground lessor. Promptly following the request of any such
purchaser, grantee, or ground lessor, Tenant shall execute and deliver a new
lease, in the form of this Lease, with such requesting party as the Landlord.
Tenant agrees to execute any documents required to effectuate such subordination
or to make this Lease prior to the lien of any mortgage, deed of trust or ground
lease, as the case may be, or to evidence such attornment.

                                       24
<PAGE>

                  (b) Tenant shall give any holder of a first mortgage or deed
of trust placed upon the Building ("Holder"), in compliance with the notice
provisions of this Lease , a copy of any notice of default served upon Landlord,
provided that prior to such notice Tenant has been notified in writing (by way
of notice of assignment of rents and leases or otherwise) of the address of such
Holder. If Landlord shall have failed to cure such default within thirty (30)
days or such longer period of time as Landlord shall have the right to cure the
default the Lease, Holder shall have the right, but not the duty, to cure such
default within an additional thirty (30) day period or if such default cannot be
cured within that time, then such additional time as may be necessary to cure
such default, including the time necessary to foreclose or otherwise terminate
its first mortgage or deed of trust is necessary to effectuate such cure.

         20. ATTORNEYS' FEES. If either party commences an action or proceeding
against the other party arising out of or in connection with this Lease, or
institutes any proceeding in a bankruptcy or similar court which has
jurisdiction over the other party or any or all of its property or assets, the
prevailing party in such action or proceeding and in any appeal in connection
therewith shall be entitled to have and recover from the unsuccessful party
reasonable attorneys' fees, court costs, expenses and other costs of
investigation and preparation. If such prevailing party recover a judgment in
any such action, proceeding, or appeal, such attorneys' fees, court costs and
expenses shall be included in and as a part of such judgment.

         21.      SURRENDER OF PREMISES.

                  (a) Upon the termination of this Lease, Tenant shall surrender
and vacate the Premises (including, without limitation, as to Roof Equipment and
signage) immediately and deliver possession thereof to Landlord in a clean, good
and tenantable condition, ordinary wear and tear, acts of God, casualties,
condemnation, Hazardous Materials (other than those released by Tenant), Tenant
Additions or other improvements which Tenant is not required to remove at the
termination of the Lease and damage caused by Landlord excepted. Under no
condition shall Tenant be required to remove any of the initial Tenant
Improvements constructed in the Premises. Tenant shall deliver to Landlord all
keys to the Premises and the Building. Tenant shall remove from the Premises all
movable personal property of Tenant and Tenant's trade fixtures. Tenant shall be
entitled to remove such Tenant Additions, which at the time of their
installation Landlord and Tenant agreed may be removed by Tenant. Tenant shall
also remove such other Tenant Additions as required by Landlord, including any
Tenant Additions containing Hazardous Materials. Tenant immediately shall repair
all damage resulting from removal of any of Tenant's property, furnishings or
Tenant Additions, shall close all floor, ceiling and roof openings and shall
restore the Premises and the Building. If any of the Tenant Additions which were
installed by Tenant involved the lowering of ceilings, raising of floors or the
installation of specialized wall or floor coverings or lights, then

                                       25
<PAGE>

Tenant shall also be obligated to return such surfaces to their condition prior
to the commencement of this Lease or their installation, as the case may be. In
the event Tenant shall fail to remove those item described above, Landlord may
(but shall not be obligated to), at Tenant's expense, remove any of such
property and store, sell, or otherwise deal with such property as provided by
law.

                  (b) All property which may be removed from the Premises by
Landlord shall be conclusively presumed to have been abandoned by Tenant and
Landlord may deal with such property as provided by law. Tenant shall also
reimburse Landlord for all costs and expenses incurred by Landlord in removing
any of Tenant Additions and in restoring the Premises to the condition required
by this Lease at the termination date.

         22. NOTICES. All notices, consents, demands and other communications
from one party to the other given pursuant to the terms of this Lease shall be
in writing and shall be deemed to have been fully given three (3) days after
deposited in the United States mail, certified or registered, postage prepaid,
or one (1) day after delivered to a generally recognized overnight courier
service, charges prepaid, and addressed as follows: to Tenant at the address
specified in the Basic Lease Information or to such other place as Tenant may
from time to time designate in a notice to Landlord, to Landlord at the address
specified in the Basic Lease Information, or to such other place and with such
other copies as Landlord may from time to time designate in a notice to Tenant.

         23.      ROOF REPAIRS.

                  (a) During the term Tenant shall have the right to use the
roof of the Building in any lawful manner and install equipment thereon (the
"Roof Equipment") subject to the following terms and conditions: Tenant shall
not penetrate the roof in connection with, any installation or reinstallation of
the Roof Equipment without Landlord's prior written consent which shall not be
unreasonably withheld.. The plans and specifications for all the Roof Equipment
shall be delivered by Tenant to Landlord for Landlord's review and approval.
Such plans and specifications, including, without limitation, the proposed
location of the Roof Equipment, shall be approved by Landlord in writing prior
to any installation. Prior to the commencement of any installation or other work
performed on or about the roof, Landlord shall approve all contractors and
subcontractors which shall perform such work. Tenant shall be responsible for
any damage to the roof, conduit systems or other portions of the Building or
Building system as a result of Tenant's installation, maintenance and/or removal
of the Roof Equipment.

                  (b) Tenant, at Tenant's sole cost and expense, shall comply
with all laws regarding the installation, construction, operation, maintenance
and removal of the Roof Equipment and shall be solely responsible for obtaining
and maintaining in force all permits, licenses and approvals necessary for such
operations.

                                       26
<PAGE>

                  (c) Tenant shall maintain the Roof Equipment in good condition
and repair, at Tenant's sole cost and expense. If an event of default exists due
to Tenant's failure to repair and maintain the Roof Equipment in accordance with
this Lease, Landlord may, but shall not be obligated to, make any such repairs
or perform any maintenance to the Roof Equipment and Tenant shall reimburse
Landlord upon demand for all costs and expenses incurred by Landlord in
connection therewith, plus a reasonable administrative fee.

                  (d) Tenant shall indemnify, defend, protect and hold harmless
Landlord from and against any and all claims related to the Roof Equipment or
operation, of the same as if the Roof Equipment were located wholly within the
Premises. Tenant shall provide evidence satisfactory to Landlord that Tenant's
property and liability insurance policies required undo this Lease include
coverage for the Roof Equipment and any claim, loss damage. or liability
relating to the Roof Equipment.

                  (e) Tenant shall, at Tenant's sole cost and expense, remove
such portions of the Roof Equipment as Landlord may designate upon the
expiration or earlier termination of this Lease, and restore the affected are to
their condition prior to installation of the Roof Equipment. If Tenant fails to
so remove the Roof Equipment, Landlord reserves the right to do so, and the
expense of the same shall be immediately due and payable from Tenant to Landlord
as additional rent, together with interest and late charges as provided in this
Lease, plus a reasonable administrative fee.

         24.      SIGNAGE RIGHTS.

                  (a) As of the Effective Date, there is a Lease Agreement dated
January 17, 1997 between Landlord, as successor-in-interest, and Foster Media,
Inc. ("Foster"), wherein Landlord leases to Foster the entire west wall of the
Building, which views to traffic traveling east on 20th Street, for wallscape
advertising. Tenant shall retain all rights of the Landlord under such lease
with Foster, including the collection of rent thereunder. Furthermore, Tenant
shall be entitled to any and all further signage which may be available on the
exterior or roof of the Building. Such signage rights are subject to the
following terms and conditions:

                  (b) Tenant shall submit plans and drawings for such signage to
the City of Oakland and to any other public authorities having jurisdiction and
shall obtain written approval from each such jurisdiction prior to installation
of such signage, and shall fully comply with all applicable laws related
thereto.

                  (c) Tenant shall, at Tenant's sole cost and expense,
design, construct and install such signage.

                                       27
<PAGE>

                  (d) All signs shall be subject to Landlord's prior written
approval, which approval shall not be unreasonably withheld.

                  (e) Tenant shall maintain its signage in good condition and
repair, and all costs of maintenance and repair shall be borne by Tenant.
Maintenance shall include, without limitation, cleaning and, if such signage is
illuminated, relamping at reasonable intervals. Tenant shall be responsible for
any electrical energy used in connection with its signs.

         Upon the expiration or earlier termination of this Lease or at such
other time that Tenant's signage rights are terminated pursuant to the term
hereof, Tenant shall cause Tenant's signage to be removed from the Building and
the Building to be repaired and restored to the condition which existed prior to
the installation of Tenant's signage (including, if necessary. the replacement
of any precast concrete panels), all at Tenant's sole cost and expense, without
further notice from Landlord notwithstanding anything to the contrary contained
in this Lease.

         25. RIGHT OF FIRST OFFER TO PURCHASE. Landlord hereby grants Tenant the
first right, option and opportunity to purchase the Premises on the following
terms and conditions;

                  (a) If at any time during the term of this Lease (including,
without limitation, any option term) Landlord desires to sell or otherwise
transfer (a "Transfer") the Premises or any part thereof or interest therein
(such part or interest being referred to herein as the "Offered Interest"), then
before Landlord enters a binding agreement to sell the Offered Interest,
Landlord shall first offer to Tenant the opportunity to purchase the Offered
Interest by giving Tenant written notice of the terms and conditions on which
Landlord would be willing to sell the Offered Interest ("Landlord's Offer").
Landlord's Offer shall include the following basic business terms upon which
Landlord is willing to transfer the Offered Interest (i) the sales price, (ii)
the amount and terms of any seller financing, (iii) the amount and terms of any
assumable third party financing, (iv) the state of title to be transferred by
Landlord, (v) the date for close of escrow, (vi) the allocation of closing
costs, (vii) the legal description of the Offered Interest, and (viii) all other
material business terms on which Landlord is willing to transfer the Offered
Interest. Tenant shall thereafter have the exclusive right to purchase the
Offered Interest on the terms and conditions stated in Landlord's Offer, which
right Tenant may exercise by giving Landlord written notice of Tenant's exercise
of such right within thirty (30) days following date that Tenant receives
Landlord's Offer. If Tenant exercises such right, then Tenant shall purchase and
Landlord shall sell the Offered Interest on the terms and conditions described
in Landlord's Offer.

                  (b) If Tenant does not, within such thirty (30) day period,
exercise Tenant's right to purchase the Offered Interest on the terms and
conditions of Landlord's

                                       28
<PAGE>

Offer, then Landlord may sell the Offered Interest to any third party for a
purchase price not less than ninety-five Percent (95%) of the purchase price
specified in Landlord's Offer and otherwise on the same term and conditions as
Landlord's Offer, so long as (i) Landlord enters a binding written agreement
with such third party for the sale of the Offered Interest within six (6) months
after Landlord's delivery to Tenant of Landlord's Offer, and (ii) Landlord
conveys title to the Offered Interest to such third party pursuant to such
agreement within one hundred twenty (120) days after such agreement for the sale
of the Offered Interest is fully executed by Landlord and such third-party
buyer.

                  (c) If Landlord has not entered a binding written agreement
for the sale of the Offered Interest within six (6) months after Landlord's
delivery to Tenant of Landlord's Offer, or if Landlord has not conveyed title to
the Offered Interest to such third-party buyer pursuant to such an agreement
within one hundred and twenty (120) days after such agreement for the Sale of
the Offered Interest is fully executed by Landlord and such third-party buyer,
then, in either such event, any subsequent offer or election by Landlord to
transfer the Premises or any part thereof or any interest therein (including,
without limitation, the Offered Interest) shall be deemed a new determination to
so do and shall be subject once again to Tenant's first right, option and
opportunity to purchase as described herein.

         26. ADDITIONAL TERMS OF PURCHASE. If Tenant elects to purchase the
Premises pursuant to any purchase option or right of first offer granted by
Landlord to Tenant under the Lease and this Addendum, then the following
additional terms and conditions will apply to such purchase:

                  (a) Landlord shall convey to Tenant at close of escrow by
Grant Deed fee simple title to the Premises, free and clear of any taxes,
assessments, liens, encumbrances or other exceptions to title, other than such
matters as may exist as of the Commencement Date of the Lease or as agreed to by
Tenant (the "Permitted Exceptions"). Tenant's obligation to purchase the
Premises shall be conditioned upon Tenant's obtaining at close of escrow an ALTA
extended coverage owner's policy of title insurance excluding all pre-printed
exceptions (the "Title Policy") naming Tenant as the insured in the amount of
the Purchase Price and showing fee title to the Premises as vested in Tenant
subject only to the Permitted Exceptions. If Tenant is unable to obtain such a
Tide Policy, Tenant may elect, in Tenant's sole discretion, to pursue any or all
of the following courses: (i) accept the title insurance policy that can be
obtained and close the purchase of the Premises, (ii) accept a title insurance
policy with one or more exceptions to title which are not Permitted Exceptions,
(iii) delay the closing date to allow Landlord to remove any exception which is
not a Permitted Exception, in which event Landlord shall use all reasonable
efforts to remove such exceptions prior to the extended closing date, or (iv)
rescind Tenant's exercise of the purchase option or the right of first offer.

                                       29
<PAGE>

                  (b) The sale and purchase of the Premises shall be consummated
through an escrow established with a reputable title company selected by Tenant
(the "Escrow Holder"). Close of escrow shall occur on the date specified by
Tenant in its notice of exercise of the purchase option or right of first
refusal, which date shall not be earlier than thirty (30) nor more than ninety
(90) days after Tenant's notice of exercise. Prior to the scheduled closing
date. Landlord and Tenant shall execute and deliver to Escrow Holder all escrow
instructions, deeds, assignments, and other documents as may be necessary to
close the purchase and sale.

                  (c) There shall be no proration of any amounts paid by Tenant
for insurance, maintenance or utilities. Tenant shall pay all Monthly Base Rent
and additional rent and all other obligations that accrue under the Lease prior
to the close of escrow; provided, however, that all Monthly Base Rent and
additional rent shall be prorated between Landlord and Tenant as of the close of
escrow with Tenant being refunded any prepayments of such sums and Landlord
receiving any underpaid amounts through the day immediately preceding close of
escrow. Any taxes, assessments, liens, encumbrances or other exceptions to title
which are not Permitted Exceptions shall be paid and satisfied by Landlord at
close of escrow. All costs of title, escrow, transfer taxes, and other closing
costs (except as otherwise specifically provided herein) shall be paid by
Landlord and Tenant in accordance with local custom in Alameda County as
determined by the Escrow Holder.

                  (d) Risk of loss of the Premises shall remain with Landlord,
subject to the terms of the Lease, until close of escrow, notwithstanding
possession of the Premises by Tenant under the terms of the Lease.

         27.      GENERAL PROVISIONS.

                  (a) The invalidity of any provision of this Lease as
determined by a court of competent jurisdiction, shall in no way affect the
validity of any other provision hereof.

                  (b) This Lease contains all agreements of the parties with
respect to any matter mentioned herein and supersedes any verbal and any prior
written conditions, representations, agreements or covenants, and may be
modified in writing only, signed by the parties.

                  (c) No waiver by Landlord or Tenant of any provision hereof
shall be deemed a waiver of any other provision or of any subsequent breach by
Tenant or Landlord of the same or any other provision. Landlord's consent to or
approval of any act shall not be deemed to render unnecessary the obtaining of
Landlord's consent to or approval of any subsequent act by Tenant. The
acceptance of rent or any partial payment hereunder by Landlord shall not be a
waiver of any preceding breach by Tenant of any

                                       30
<PAGE>

provision hereof, other than the failure of Tenant to pay the particular rent
accepted, regardless of Landlord's knowledge of such preceding breach at the
time of acceptance of such rent.

                  (d) If Tenant remains in possession of the Premises or any
part thereof after the expiration of the term with the consent of Landlord, such
occupancy shall be a tenancy from month to month at a rental in the amount of
one and one-half times the last month's rental during the term plus all other
charges payable hereunder, and upon all of the terms hereof.

                  (e) Subject to the provisions of this Lease restricting
assignment or subletting by Tenant, this Lease shall bind the parties, their
personal representatives, successors and assigns.

                  (f) Landlord and Landlord's agents shall have the right to
enter the Premises at reasonable times (with reasonable prior notice) for the
purpose of inspecting the same, showing the same to prospective purchasers or
lenders, and making such alterations, improvements or additions to the Premises
or to the Building as Landlord may deem necessary or desirable. Landlord may at
any time during the last one hundred twenty (120) days of the term place on or
about the Premises any ordinary "For Lease" sign. Landlord shall comply with
Tenant's security and operating restrictions and shall use reasonable efforts to
minimize any interference with Tenant's operations.

                  (g) If Tenant is a corporation, limited liability company or
other entity, Tenant represents that each individual executing this Lease on
behalf of Tenant is duly authorized to execute and deliver this Lease on behalf
of the entity and that this Lease is binding upon the entity in accordance with
its terms.

                  (h) The term "Landlord" as used herein means the then owner of
the Building and in the event of a sale of the Building the selling owner shall
be automatically relieved of all obligations of Landlord thereafter accruing
hereunder.

                  (i) Tenant covenants for itself, its heirs, executors,
administrators, and assigns and all persons claiming under or through it, and
this Lease is made and accepted upon it subject to the condition that there
shall be no discrimination against or segregation of any person or group of
persons, on account of race, color, creed, religion, sex, marital status
national origin, or ancestry in the leasing, subleasing, transferring, use,
occupancy, tenure, or enjoyment of the Premises herein leased nor shall the
Tenant itself, or any person claiming under or through it, establish or permit
any such practice or practices of discrimination or segregation with reference
to the selection, location, number, use, or occupancy of tenants, subtenants, or
vendees in the Premises.

                                       31
<PAGE>

                  (j) GOVERNING LAW; WAIVER OF TRIAL BY JURY. THIS LEASE SHALL
BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH THE LAW 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) 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 WITH THIS LEASE, TENANT'S USE OR OCCUPANCY OF THE PREMISES, AND/OR
ANY STATUTORY REMEDY.

                  (k) No diminution or shutting off of light, air or view by any
structure which may be erected on lands adjacent to the Building shall in any
way affect this Lease or impose any liability on Landlord.

                  (l) This Lease shall not be recorded. Landlord and Tenant
agree to execute and acknowledge, at the request of either, a memorandum of this
Lease, in recordable form.

                  (m) Whenever the Lease requires an approval, consent,
designation, determination, selection or judgment by either Landlord or Tenant,
such approval, consent, designation, determination, selection or judgment and
any conditions imposed thereby shall be reasonable and shall not be unreasonably
withheld or delayed and, in exercising any right or remedy hereunder, each party
shall at all times act reasonably and in good faith.

                  (n) Any expenditure by a party permitted or required under the
Lease, for which such party is entitled to demand and does demand reimbursement
from the other party, shall be limited to the fair market value of the goods and
services involved, shall be substantiated by documentary evidence available for
inspection and review by the other party or its representative during normal
business hours.

                                       32
<PAGE>

         28. EXHIBITS. The exhibits, if any, specified in the Basic Lease
Information are attached to this Lease and by this reference made a part hereof.

         IN WITNESS WHEREOF, the parties have executed this Lease to on the
respective dates indicated below.

TENANT:                                LANDLORD:

DoubleTwist, Inc.,                     First Broadway/20th, LLC,
a California corporation               a California limited liability company

By:                                    By:  /s/ Steven R. Meckfessel
      ------------------------------        ------------------------------
Name:                                  Name:  Steven R. Meckfessel
      ------------------------------        ------------------------------
Its:                                   Its:  Managing Member
      ------------------------------        ------------------------------
Date:                                  Date:  5/17/00
      ------------------------------        ------------------------------

By:  /s/ John Couch                    By:
      ------------------------------        ------------------------------
Name:  John Couch                      Name:
      ------------------------------        ------------------------------
Its:  CEO                              Its:
      ------------------------------        ------------------------------
Date:                                  Date:
      ------------------------------        ------------------------------

                                       33
<PAGE>

                                    EXHIBIT A

                                    [DIAGRAM]

<PAGE>

                                    EXHIBIT B

                       INITIAL IMPROVEMENT OF THE PREMISES

         THIS EXHIBIT is incorporated into that certain Lease (the "Lease") by
and between First Broadway/20", LLC, a California limited company ("Landlord")
and DoubleTwist, Inc., a California corporation ("Tenant"). All of the defined
terms as used in the Lease shall have the same meanings herein.

         1. LANDLORD'S WORK. Landlord, through its general contractor, shall
perform certain improvements to the Building shell and core at its sole cost and
expense prior to delivery of the Premises to Tenant ("Landlord's Work").
Landlord's Work shall include those items specifically denoted on Schedule B-1
attached hereto and made a part of this Lease.

         2. TENANT IMPROVEMENTS. Landlord, through its general contractor, shall
furnish and install within the Premises in accordance with the drawings and
specifications finally approved by Landlord and Tenant (collectively, the
"Tenant Improvement Drawings"), partitions. doors, lighting fixtures, glazing,
millwork, painting, systems (mechanical, electrical, sprinklers) distribution,
plumbing (outside of restrooms) and other items of general construction (the
"Tenant Improvements"). The quantities, character and manner of installation of
all of the Tenant Improvements shall be subject to the limitations imposed by
any applicable laws and governmental regulations.

         3. ALLOCATION OF COST. Landlord shall bear the cost of all Tenant
Improvements up to an amount equal to $1,777,608 (the "Tenant Improvement
Allowance"). In addition, Landlord shall bear the cost of all permits,
architectural and engineering services related to the Tenant Improvements based
on the Tenant Improvement Allowance budget. Tenant shall bear the cost of all
such Tenant Improvements, permits and services in excess of the Tenant
Improvement Allowance. Landlord shall pay a share of each progress billing from
its general contractor determined by multiplying the amount of such billing by a
fraction, the numerator of which is the Tenant Improvement Allowance, and the
denominator of which is the estimated construction cost of all Tenant
Improvements to be installed in the Premises and permits required therefor.
Tenant shall pay the balance of each progress billing, provided that at such
time as Landlord has paid the Tenant Improvement Allowance, all billings shall
be paid entirely by Tenant.

         4. PAYMENT OF TENANT'S COST. Tenant shall pay to Landlord all amounts
due under the terms of this "Exhibit B" within ten (10) business days after
billing by Landlord (but not more frequently than once per month). Bills may be
rendered during the development of the Tenant Improvement Drawings and the
Tenant Improvements so as to enable Landlord to pay permit and processing fees
and its architects, engineers and

                                      B-1
<PAGE>

general contractor without advancing Landlord's funds for more than its share of
each progress billing. Landlord shall not be obligated to continue installation
of the Tenant Improvements, if Tenant does not pay its share of the cost of the
Tenant Improvements to Landlord within ten (10) days of when due. If Tenant does
not make timely payment to Landlord, Landlord may, but shall not be obligated
to, advance Landlord's funds to pay Tenant's share of the cost of the Tenant's
Improvements and any funds so advanced shall be payable to Landlord upon demand
as additional rent and shall bear interest as provided in paragraph 3 of the
Lease.

         5.       DRAWINGS AND SPECIFICATIONS.

                  (a) Tenant shall approve the preliminary space plan as
prepared by Landlord's Architect no later than May 3, 2000. Landlord, through
its architects and engineers, shall prepare construction drawings as quickly as
possible for the pricing and construction of the Tenant Improvements. Such
construction drawings shall conform to and represent logical evolutions of the
preliminary space plan previously approved by Tenant. Tenant shall provide
Landlord's architects and engineers with sufficient instructions, as described
below, to enable Landlord's architects and engineers to prepare complete
drawings and specifications for the Tenant Improvements.

                  (b) Tenant's instructions to Landlord's architects and
engineers shall include all relevant information, including, without limitation,
Tenant's budget, special floor loadings, floor openings, air conditioning,
plumbing and electrical loads, location and size of equipment, location and size
of all of the functional requirements and the nature of desired finishes,
casework, millwork, lighting and any special acoustic, fire-proofing and other
treatments. Tenant and Landlord shall diligently pursue preparation of all such
plans and specifications which shall be subject to approval by Landlord. If
information submitted by Tenant is not sufficient for Landlord's purposes,
Landlord or its architects or engineer shall so notify Tenant within three (3)
days after receipt of such information specifying the required additional
information. Within three (3) days thereafter, Tenant shall provide the
additional information to Landlord in a form sufficient to permit Landlord, its
architects and engineers, and general contractor to proceed with the design and
construction of the Tenant Improvements. In the course of the preparation of
construction drawings, Tenant and Landlord's architects and engineers shall
consult with each other to facilitate Tenant's approval thereof when completed.
Tenant shall approve the final construction drawings within five (5) days of
delivery.

                  (c) Concurrent with the preparation of the Tenant Improvement
Drawings by Landlord's architect and engineers, Landlord shall obtain
preliminary cost estimates from its general contractor and relay such
information to Tenant. Upon completion and approval of the Tenant Improvement
Drawings by Landlord and Tenant, Landlord shall obtain and submit to Tenant a
quotation of the cost of the Tenant

                                      B-2
<PAGE>

Improvements from Landlord's contractor. Tenant shall have the right to review
all pricing information obtained by Landlord. If the quotation is not greater
than one hundred five percent (105%) of the Tenant Improvement Allowance, then
the quotation shall be deemed approved by Tenant. If the quotation is greater
than one hundred five percent (105%) of the Tenant Improvement Allowance, Tenant
shall approve or disapprove such estimate within five (5) business days of
delivery. If disapproved, within five (5) business days following disapproval
Tenant shall provide Landlord with additional information adequate to permit the
revision of the Tenant Improvement Drawings and repricing of the Tenant
Improvements.

                  (d) As soon as approved by Landlord and Tenant, Landlord shall
submit the approved Tenant Improvement Drawings to all appropriate governmental
agencies and thereafter Landlord shall use its best efforts to obtain all
required governmental approvals as soon as possible. No changes may be made in
the approved Tenant Improvement Drawings without Landlord's and Tenant's
approval (not to be unreasonably withheld).

         6. CHANGE TO TENANT IMPROVEMENTS. Tenant shall bear the cost of any
changes in the Tenant Improvements requested by Tenant after final approval of
the Tenant Improvement Drawings by Tenant, together with a fee for Landlord's
construction administration in an amount not to exceed five percent (5%) of the
cost of such changes. In the event Landlord or its general contractor is
instructed by Tenant to proceed with such changes without approval of such cost
by Tenant, the amount thereof shall be as determined by Landlord upon completion
of the Tenant Improvements, subject only to Landlord's furnishing to Tenant
appropriate back-up information from Landlord's general contractor concerning
increased costs and construction delays.

         7. TENANT'S VENDORS.

                  (a) Any items or work beyond the scope of the normal
construction trades for which Tenant contracts separately (hereinafter "Tenant
Vendor's Work"), shall be subject to Landlord's and its contractor's reasonable
policies and schedules and shall be conducted in such a way as not to hinder,
cause any disharmony with or delay Landlord's completion of the Tenant
Improvements. To this end, Tenant shall conform with a schedule determined by
Landlord's contractor and no work shall be done by Tenant which would cause
Landlord's contractor to be dependent upon such work for completion of
Landlord's contractor's work. If required by Landlord's contractor in order to
avoid labor disputes, all of Tenant Vendor's Work shall be done with union labor
in accordance with any applicable Master Labor Agreement. In no event shall work
involving the roof, sprinkler, plumbing, mechanical, electrical, telephone,
lighting or life safety systems of the Building be performed by other than
Landlord's approved

                                      B-3
<PAGE>

subcontractors and all telecommunications and other special electrical equipment
shall be installed under the supervision of Landlord's electrical subcontractor.

                  (b) Not less than five (5) days prior to the date Tenant
desires to commence Tenant Vendor's Work, it shall give a written request to
Landlord setting forth or accompanied by all of the following:

                           (1)      A description and schedule for the work to
                                    be performed;

                           (2)      The names and addresses of all contractors,
                                    subcontractors and material suppliers who
                                    will perform Tenant Vendor's Work;

                           (3)      The approximate number of individuals,
                                    itemized by trade, who will be present in
                                    the Premises;

                           (4)      Copies of all plans and specifications
                                    pertaining to that portion of the Tenant
                                    Vendors Work;

                           (5)      Copies of all licenses and permits which may
                                    be required in connection with the
                                    performance of Tenant Vendor's Work;

                           (6)      Certificates of insurance indicating
                                    compliance with the insurance requirements
                                    set forth in the Lease; and

                           (7)      If the cost of such Tenant Vendor's Work
                                    will exceed $100,000, performance and labor
                                    and materials payments bonds in an amount
                                    not less than Landlord's reasonable estimate
                                    of the total cost of such Tenant Vendor's
                                    Work; and, at Landlord's request, evidence
                                    of the availability of funds sufficient to
                                    pay for all such work.

All of the foregoing shall be subject to Landlord's approval, which approval
shall not unreasonably be withheld.

                  (c) Tenant shall be responsible for any expenses incurred by
Landlord due to inadequate cleanup by those performing Tenant Vendor's Work.

                  (d) If, in Landlord's opinion, any supplier, contractor or
worker performing Tenant Vendor's Work hinders or delays, directly or
indirectly, any other work of improvement in the Building or performs any work
which may or does impair the quality, integrity or performance of any portion of
the Building, Landlord may give notice thereof to Tenant and, if such condition
has not been remedied within forty-eight

                                      B-4
<PAGE>

(48) hours, then promptly thereafter, Tenant shall cause such supplier,
contractor or worker immediately to remove all of its tools, equipment and
materials and to cease working in the Building. As additional rent under the
Lease, Tenant shall reimburse Landlord for any repairs or corrections of the
improvements constituting the Premises or any portion of the Building, or for
the cost of any delays caused by or resulting from the actions or omissions of
anyone performing Tenant Vendor's Work.

         8. SUBSTANTIAL COMPLETION AND RENTAL COMMENCEMENT DATE. "Substantial
Completion" shall be defined as the completion of the Landlord's Work and Tenant
Improvements, as the case may be, except for minor, insubstantial details of
construction, decoration or mechanical adjustments which remain to be done, the
correction or completion of which will not materially interfere with Tenant's
use and occupancy of the Premises, as determined by Landlord's architect.
Notwithstanding anything to the contrary contained in the Lease, Tenant's
obligation for payment of rental under the Lease shall not commence until
Landlord gives notice to Tenant that the Tenant Improvements are Substantially
Completed. If Landlord is delayed in substantially completing the Tenant
Improvements as a result of the following events (each of which is referred to
herein as a "Tenant Delay"):

                  (a) Tenant's delay in approving the preliminary space plan
by May 3, 2000;

                  (b) Tenant's changes to the preliminary space plan as finally
approved by Tenant which results in substantial differences in the program
previously prepared and priced by Landlord in calculating the Tenant Improvement
Allowance;

                  (c) Tenant's changes to the construction drawings after
approval thereof pursuant to paragraph 4(c) of this Exhibit B;

                  (d) Tenant's request for changes in the Tenant Improvements
after commencement of construction;

                  (e) Hindrance or disruption of the work of Landlord's
contractor resulting from Tenant Vendor's Work or any other reason under
Tenant's control; or

                  (f) Cessation or termination of work in the Premises due to
Tenant's failure to pay when due all amounts payable by Tenant pursuant to this
Exhibit B;

         then the commencement date of Tenant's obligation for payment of rental
shall be advanced by the number of days that Substantial Completion was actually
delayed by such delay.

                                       B-5
<PAGE>

         9. DELIVERY. Effective upon delivery of the Premises to Tenant,
Landlord warrants that (i) all Landlord's Work and the construction of the
Tenant Improvements was performed in accordance with all Laws and the final
approved Landlord Plans and Tenant Improvement Drawings and in a good and
workmanlike manner, and (ii) all material and equipment installed in the
Premises conformed to such approved Landlord Plans and Tenant Improvement
Drawings and was new and otherwise of good quality.

         10. EARLY ENTRY FOR EQUIPMENT FIT UP. So long as such occupancy does
not interfere with Landlord's construction of the Tenant Improvements, Tenant
shall have the right to occupy the Premises prior to substantial completion of
the Tenant Improvements for the purpose of installing Tenant's equipment, data
and telecommunications systems, and trade fixtures. Any such occupancy shall be
subject to all of the terms of the Lease except the obligation to pay rent.

TENANT:                                  LANDLORD:
DoubleTwist, Inc.,                       First Broadway/20th, LLC,
a California corporation                 a California limited liability company

By:  /s/ John Couch                      By:   /s/ Steven R. Meckfessel
     --------------------------------          ------------------------------
Name:  John Couch                        Name:  Steven R. Meckfessel
     --------------------------------          ------------------------------
Its:  CEO                                Its:  Managing Member
     --------------------------------          ------------------------------
Date:                                    Date:  5/17/00
     --------------------------------          ------------------------------

By:                                      By:
     --------------------------------          ------------------------------
Name:                                    Name:
     --------------------------------          ------------------------------
Its:                                     Its:
     --------------------------------          ------------------------------
Date:                                    Date:
     --------------------------------          ------------------------------

                                      B-6
<PAGE>

                                  SCHEDULE B-1

                                 LANDLORD'S WORK

         1.       Voluntary seismic upgrade improvements to Building structure,
                  including installation of concrete shear walls, diagonal
                  bracing and reinforcing of existing concrete walls as
                  necessary throughout the Building.

         2.       Windows and perimeter walls will be repaired, as necessary,
                  sealed and finished to a water-tight condition (to the extent
                  possible consistent with the Historic Guidelines). Facade
                  "touch-ups" to repair minor damage and generally clean up the
                  exterior of the Building.

         3.       Upgrade of existing stairs to meet current egress code and ADA
                  regulations. Generally this will include extending the second
                  stair to the first floor and basement and enclosing both
                  stairs.

         4.       To accommodate Tenant's general office use only, construction
                  of new men's and women's restrooms (not including showers) on
                  each main floor of the Premises in compliance with all
                  applicable code requirements.

         5.       Reuse of existing electrical service and rough installation to
                  each main floor, restrooms, elevator and stair. Distribution
                  of electrical system within the Premises is part of the Tenant
                  Improvement work.

         6.       New mechanical rough-in system to make available required HVAC
                  to each floor, including vertical HVAC distribution between
                  floors and distribution to and from the Building core
                  (restrooms, stairways and adjacent storage room) but not the
                  horizontal HVAC duct loops on each floor. Distribution of HVAC
                  system is part of the Tenant Improvement work. Any additional
                  mechanical and electrical requirements for equipment other
                  than Tenant's is not included in the Landlord's Work.

         7.       Replacement of roof, with reuse of existing roof drainage
                  system.

         8.       Retrofit of existing elevators as per existing contract with
                  Otis Elevator Company.

         9.       Installation of sprinkler system to each floor, elevator, and
                  restrooms, including but not limited to, mains, standpipes,
                  heads and laterals, as required by applicable code
                  requirements for open shell construction. Distribution of
                  sprinklers within the leased Premises is put of Tenant
                  Improvement work.

                                      B-7
<PAGE>

         10.      Installation of fire alarm systems per all applicable code
                  requirements.

         11.      Lead paint removal and abatement from interior window frames
                  and stair railings.

         12.      Rectification of deficiencies, if any, in the structural
                  elements of the Building to comply with all codes, ordinances,
                  laws, and regulations applicable as of the date of this
                  Agreement, including, but not limited to, fire and life-safety
                  provisions, building codes, and handicaps and ADA requirements
                  relating to the base building, but excluding any modifications
                  required solely as a result of Tenant's build-out or
                  particular use of the Premises or which are triggered solely
                  by the Tenant Improvements, alterations or additions.

                  The final plans for Landlord's Work are being completed as of
                  the date of this Lease and therefore the exact plans together
                  with specific specifications and plans are subject to changes
                  based upon all governmental requirements and physical
                  limitations. Such final plans ("Landlord Plans") shall be
                  subject to Tenant's reasonable approval, and no changes may
                  thereafter be made to the approved Landlord Plans without
                  Tenant's further approval.

                                      B-8
<PAGE>

                                    EXHIBIT C

                             VERIFICATION MEMORANDUM

         Re: Lease dated as of April 12, 2000 between First Broadway/20th, LLC,
a California limited liability company, ("Landlord"), and DoubleTwist, Inc., a
California corporation ("Tenant"), and for Premises known as 2001 Broadway,
Oakland, California. Tenant hereby verifies that the dates and amounts stated
below are correct and further acknowledges and accepts possession of the
Premises.

Area:                          63,486 square feet

Commencement Date:             ----------------------------------

Expiration Date:               ----------------------------------

Initial Monthly Base Rent:     $

TENANT:                                LANDLORD:
DoubleTwist, Inc.,                     First Broadway/20th, LLC,
a California corporation               a California limited liability company

By:  /s/ John Couch                    By:
     ----------------------------            ----------------------------
Name:  John Couch                      Name:
     ----------------------------            ----------------------------
Its:  CEO                              Its:
     ----------------------------            ----------------------------
Date:                                  Date:
     ----------------------------            ----------------------------

By:                                    By:
     ----------------------------            ----------------------------
Name:                                  Name:
     ----------------------------            ----------------------------
Its:                                   Its:
     ----------------------------            ----------------------------
Date:                                  Date:
     ----------------------------            ----------------------------

                                      C-1<PAGE>

           DOUBLETWIST DISTRIBUTION AND VALUE-ADDED RESELLER AGREEMENT

Agreement made this 24th day of March, 2000 ("Effective Date") by and between
DoubleTwist, Inc. ("DoubleTwist") having its principal offices at 1999 Harrison
Street, Suite 1100, Oakland, CA 94612, and Hitachi, Ltd., including its
subsidiaries and affiliates in which 50% or more of the stock is directly or
indirectly controlled by Hitachi, Ltd. ("Hitachi") having it principal offices
at 6, Kanda-Surugadai 4-Chome, Chiyoda-ku, Tokyo, 101-8010 Japan.

1.   PURPOSE. The purpose of this Agreement is to set forth the terms and
     conditions pursuant to which Hitachi will integrate and distribute to its
     customers the DoubleTwist software and/or database products described on
     the Product Description (Exhibit A) attached hereto and made a part hereof
     ("Licensed Product" or "Hitachi/DT Products").

2.   DEFINITIONS.

     (a) All terms defined in the Product Description shall have the meanings
         therein ascribed to them for purposes of this Agreement.

     (b) "Hitachi Systems" shall be defined as the computer and/or software
         systems created, marketed, distributed, and/or sold by Hitachi to the
         market, with which a Licensed Product will be integrated.

     (c) "End Users" shall be defined as current and future Hitachi customers
         who purchase from Hitachi a Hitachi/DT Product.

     (d) "Updates" shall be defined as generally available revisions to
         Hitachi/DT Products released from time to time by DoubleTwist.

     (e) "Initial Distribution" shall be defined as the initial sale of a
         Hitachi/DT Product to an End User. There will be only one (1) Initial
         Distribution to each End User.

     (f) "Upgrade" shall be defined as the license of a) a more expensive
         Licensed Product, or b) a Licensed Product with additional features, by
         End User following the Initial Distribution.

     (g) "Integration" shall be defined as the programming undertakings to be
         performed by Hitachi which are required to allow End Users functional
         access to Licensed Product features and capabilities from within
         Hitachi Systems and the logically appropriate data sharing between
         Hitachi/DT Products and Hitachi Systems.

     (h) "Hitachi/DT Product" shall be defined as 1) a Licensed Product, or 2) a
         Hitachi System integrated with a Licensed Product.

<PAGE>

"Documentation" shall be defined as the user manuals and similar materials
customarily supplied by DoubleTwist to end users of the Licensed Product.

3.   GRANT OF RIGHTS.

     (a) Subject to payment of the Distribution Fees by Hitachi to DoubleTwist
         as hereinafter provided, DoubleTwist grants to Hitachi a personal,
         exclusive, non-transferable, royalty-free right to market, distribute,
         direct to End Users, and install at End User locations in the Asia
         Pacific region ("Region") software packages comprising the Hitachi/DT
         Products, subject to the terms and conditions of this Agreement.
         Hitachi shall not transfer any Licensed Product other than in the form
         of a Hitachi/DT Product.

     (b) DoubleTwist grants Hitachi a non-exclusive, non-transferable,
         royalty-free right (i) to use and make copies of the Documentation for
         back-up and archival purposes, marketing, distribution, service and
         support of Hitachi/DTProducts and (ii) to furnish such documentation to
         End Users in connection with Hitachi's distribution of Hitachi/DT
         Products, and maintenance and support thereof.

     (c) DoubleTwist reserves all other rights to the Hitachi/DT Products which
         are not expressly specified in this Agreement.

4.   DUTIES OF DOUBLETWIST

     (a) Upon execution of this Agreement, DoubleTwist shall transmit to Hitachi
         six (6) copies of the Hitachi/DT Products and associated Documentation.
         Hitachi shall have the right to inspect the Hitachi/DT Products
         delivered by DoubleTwist to determine if they comply with the
         specifications and the warranties contained in Documentation. Hitachi
         shall have thirty (30) days from the date Hitachi/DT Products are
         shipped by DoubleTwist to Hitachi in which to notify DoubleTwist of any
         failure of the Hitachi/DT Products to conform to such specifications or
         warranties. DoubleTwist shall promptly repair or replace any such
         defect in the Hitachi/DT Products to conform to Documentation. If
         DoubleTwist fails to do so, Hitachi shall have the right to reject the
         Hitachi/DT Products. If Hitachi has not informed DoubleTwist of any
         failure of the Hitachi/DT Products during the said thirty (30) day
         period, the Hitachi/DT Products shall be deemed accepted ("Acceptance
         Date").

     (b) DoubleTwist shall provide five (5) days training for marketing,
         distribution and installation of the Licensed Product, said training to
         be completed by June 30, 2000. Hitachi employees shall be trained at
         DoubleTwist's principal offices without charges or, at Hitachi's
         election, at another site subject to Hitachi's reimbursement to
         DoubleTwist of all reasonable travel and accommodation expenses related
         to such training. DoubleTwist shall, without charge and during

                                       2
<PAGE>

         DoubleTwist's regular business hours, reply to questions asked by
         Hitachi regarding the operation and maintenance of the Licensed
         Program, by telephone, mail and E-mail, necessary for Hitachi's
         distribution, installation, maintenance, and support of the Hitachi/DT
         Products.

     (c) DoubleTwist will be responsible for Providing to Hitachi and
         maintaining Updates to the Hitachi/DT Products without charge. Updates
         will be Licensed Product specific and their frequency will be
         determined solely by DoubleTwist.

     (d) DoubleTwist will provide, without charge, back-up support of Licensed
         Product to Hitachi related to the appropriate use, error correction,
         and contents of the Hitachi/DT Products to the same extent that
         DoubleTwist provides such support for its other products generally.

5.   DUTIES OF HITACHI

     (a) Hitachi will be responsible for Integration of Hitachi/DT Products
         within Hitachi Systems and for all costs related to such Integration.

     (b) Integration of the Hitachi/DT Products will include development by
         Hitachi of programs that allow for proper operation of the Hitachi/DT
         Products within Hitachi Systems.

     (c) Hitachi will be responsible for installation and on-going support of
         Hitachi/DT Products for End Users. Hitachi shall be solely responsible
         for maintenance of Hitachi/DT Products.

     (d) Hitachi will be responsible for notifying DoubleTwist in writing of
         orders it receives for Hitachi/DT Products, per Section 7(a).

     (e) Hitachi will provide necessary and appropriate marketing services for
         the Hitachi/DT Products.

     (f) Hitachi will provide to DoubleTwist, and update in a timely manner, a
         listing of Hitachi/DT Product customers including the contact name,
         organization name, address, phone number, and type of Hitachi System.
         DoubleTwist's use of Hitachi customer information will be strictly
         limited to DoubleTwist's marketing and support activities. Such
         information shall constitute "Confidential Information" for purposes of
         Section 8, hereinbelow.

     (g) During the term of this Agreement and, in the event of any breach of
         this Agreement by Hitachi for twelve (12) months thereafter, Hitachi
         agrees not to market integrated or to integrate within Hitachi Systems,
         directly or indirectly 1) any product capable of clustering or aligning
         greater than 50,000 DNA, mRNA,

                                       3
<PAGE>

         cDNA, or non-protein consensus sequence, or 2) any database of sequence
         clusters that contains greater than 50,000 input DNA, mRNA, cDNA, or
         non-protein consensus sequences.

6.   LICENSE TERMS

     (a) Hitachi agrees that the use of the Hitachi/DT Products by End Users
         will be subject to the terms and conditions of the applicable
         DoubleTwist Software License Agreement.

     (b) Hitachi agrees to pay DoubleTwist the Distribution Fees set forth in
         the Distribution Fee Schedule of Exhibit B, attached hereto and made a
         part hereof.

     (c) In addition to the above, DoubleTwist will charge standard fees for
         shipping and handling the Hitachi/DT Products as set forth in the
         Pricing Schedule.

     (d) DoubleTwist shall, after the first anniversary of the Effective Date,
         have the right, at its sole discretion, to increase the Distribution
         Fees for the Hitachi/DT Products. DoubleTwist shall notify Hitachi
         within thirty (30) days of any such change, and Hitachi shall have and
         additional sixty (60) days from such notification to institute such
         price change within Region.

     (e) Hitachi shall, in addition to the other amounts payable under this
         Agreement, pay all sales and other taxes, federal, state, or otherwise,
         however designated, which are levied or imposed by reason of the
         transactions contemplated by this Agreement, except taxes related to
         the income of or the employees of DoubleTwist.

     (f) Hitachi agrees to notify End Users of the requirement to license third
         party coding systems or other components ("Third Party Software") for
         use in the Hitachi/DT Products. Notwithstanding any other provision of
         this Agreement, DoubleTwist shall have no liability and makes no
         warranty with regard to any such Third Party Software, and shall have
         no responsibility to procure or otherwise make available to End User
         such Third Party Software.

7.   PAYMENT TERMS AND RECORD KEEPING

     (a) Within thirty (30) days of the end of each calendar quarter, Hitachi
         will provide DoubleTwist with a report, which contains the following
         items:

         i.   A listing of the number and type of Initial Distributions of
              Hitachi/DT Products made by Hitachi during the previous calendar
              quarter;

                                       4
<PAGE>

         ii.  A listing of the number of Upgrade and Renewal sales made by
              Hitachi during the previous calendar quarter; and

         iii. The number of returns or rejections, if any, of the Hitachi/DT
              Products that occurred during the previous calendar quarter.

         Included with the report will be payment to DoubleTwist by Hitachi for
         amounts currently due, adjusted for returns and rejections. For
         purposes of illustration, Hitachi shall submit a report to DoubleTwist
         along with payment no later than July 31, 2000 for Initial
         Distributions, Upgrades sales and Renewal sales made by Hitachi in the
         second quarter, 2000.

     (b) The report described in Section 7 (a) shall be certified as correct by
         an officer of Hitachi. Hitachi shall keep accurate and correct records
         of Initial Distributions, Upgrade sales and Renewal sales in a form as
         is appropriate to determining the amount due DoubleTwist under this
         Agreement. Copies of these records shall be retained by Hitachi
         ("Hitachi Records") for at least three (3) years following a given
         quarter and shall be made available at Hitachi's principal office
         during normal business hours for inspection once each calendar year by
         DoubleTwist or its authorized representative, for the sole purpose of
         verifying reports and payments made under this Agreement. DoubleTwist
         shall notify Hitachi in writing more than sixty (60) days prior to the
         date of such inspection.

     (c) In the event that it is determined that Hitachi has inadvertently
         underreported in excess of five percent (5%) of the amounts due
         DoubleTwist over a twelve (12) month period, then in addition to the
         amount due DoubleTwist by Hitachi from such under-reporting, Hitachi
         shall also reimburse DoubleTwist the reasonable cost of such inspection
         of Hitachi's records. Following such underreporting, DoubleTwist shall
         have the right to inspect Hitachi Records once every six (6) months
         during the term of the Agreement, and in the event a subsequent
         underreporting in excess of five percent (5%) is discovered, Hitachi
         shall reimburse DoubleTwist the reasonable cost of each such
         inspection.

8.   CONFIDENTIALITY

     (a) For the purposes of this Agreement, "Confidential Information" means
         that information disclosed by each party to the other party, that is
         related to, but is not limited to, the terms and conditions of this
         Agreement, the existence of the discussions between the parties, trade
         secrets of each party, any nonpublic information relating to each
         party's product plans, designs, ideas, concepts, costs, prices,
         finances, marketing plans, business opportunities, personnel, research,
         development or know-how and any other nonpublic technical or business
         information of each party. Confidential Information does not, however,
         include information that: (a) is now or subsequently becomes generally
         available to the

                                       5
<PAGE>

         public through no fault or breach on the part of the receiving party;
         (b) the receiving party can demonstrate to have had rightfully in its
         possession without an obligation of confidentiality prior to disclosure
         hereunder; (c) is independently developed by the receiving party
         without the use of any Confidential Information of the disclosing party
         as evidenced by written documentation; or (d) the receiving party
         rightfully obtains from a third party who has the right to transfer or
         disclose it and who provides it without a confidentiality obligation.

     (b) The Confidential Information is provided for the purposes of
         facilitating the distribution of DoubleTwist's bioinformatics products
         or projects (the "Business Purpose"). The receiving party will not
         disclose, publish or disseminate Confidential Information to anyone
         other than those of its employees who need to know for the Business
         Purpose, and the receiving party will take reasonable precautions to
         prevent any unauthorized use, disclosure, publication or dissemination
         of Confidential Information. The receiving party accepts Confidential
         Information for the Business Purpose and in connection with the
         business discussions regarding the Business Purpose hereunder. The
         receiving party will not use Confidential Information other than for
         the Business Purpose for its own or any third party's benefit without
         the prior written approval of an authorized representative of the
         disclosing party in each instance. If the receiving party receives
         notice that it may be required or ordered by any judicial or
         governmental entity to disclose Confidential Information of the
         disclosing party, it will take all necessary steps to give the
         disclosing party sufficient prior notice in order to contest such
         requirement or order.

9.   INDEMNIFICATION

     (a) DoubleTwist represents and warrants to Hitachi that the Licensed
         Product were developed or licensed by DoubleTwist and, to the best of
         DoubleTwist's knowledge, do not infringe any patent, trademark,
         copyright, trade secret, or any other proprietary rights of any third
         party or parties.

     (b) DoubleTwist shall indemnify, defend and hold harmless Hitachi from all
         costs, damages or expenses (including attorney's fees) which may be
         finally assessed in any action resulting from a claim that the Licensed
         Product infringes any third party's patent, copyright, trade secret or
         any other proprietary rights and shall procure for Hitachi the right to
         continue to distribute the Licensed Product or shall make commercially
         reasonable efforts to replace or modify the same to make them
         non-infringing, which such replacement or modification shall meet the
         specifications identified in Documentation; provided that (1) Hitachi
         shall give DoubleTwist prompt written notice of any such action, claim
         or threat of suit (2) DoubleTwist shall take over, settle or defend
         such action, claim or suit through counsel of DoubleTwist's choice and
         under DoubleTwist's sole direction, and

                                       6
<PAGE>

         3) Hitachi shall cooperate fully with DoubleTwist in connection with
         such action, claim or suit.

     (c) Hitachi shall indemnify, defend and hold harmless DoubleTwist from all
         costs, damages or expenses (including attorney's fees) which may be
         finally assessed in any action resulting from a claim that any
         statement made by Hitachi in advertising, licensing or promoting the
         Hitachi/DT Products is false or misleading or for any material breach
         by Hitachi of its obligations hereunder, provided that (1) DoubleTwist
         shall give Hitachi prompt written notice of any such action, claim or
         threat of suit; (2) Hitachi shall take over, settle or defend such
         action, claim or suit through counsel of Hitachi's choice and under
         Hitachi's sole direction and at Hitachi's expense; and (3) DoubleTwist
         shall cooperate fully with Hitachi in connection with such action.

     (d) The foregoing provisions shall not apply to any infringement
         attributable to any unauthorized modification of the Hitachi/DT
         Products by Hitachi, or any portion thereof, or any use of the
         Hitachi/DT Products with additional software or devices not expressly
         authorized in writing by DoubleTwist herein.

     (e) Except for intellectual property infringement claims covered by part
         Section 9(a) and (b), Hitachi shall indemnify and hold DoubleTwist
         harmless against any liability, or any litigation cost or expense
         (including attorney's fees), arising out of third party claims against
         DoubleTwist as a result of Hitachi's use or distribution of the
         Hitachi/DT Product or Licensed Product or Documentation.

10.  WARRANTY

     (a) DoubleTwist represents and warrants that the computer programs,
         databases and/or other reports included in the Licensed Products will,
         for one (1) year from the Acceptance Date, conform to their
         then-current Documentation.

     (b) If defects in the Licensed Product are discovered by Hitachi,
         DoubleTwist agrees to make efforts to correct such defects commensurate
         with the severity of the defect at DoubleTwist's expense within ten
         (10) days following receipt of notice from Hitachi of such defects.
         After correction of the such defects, Hitachi will inspect such
         Hitachi/DT Products as provided in Paragraph 4(a) of this Agreement.

     (c) EXCEPT AS SPECIFICALLY PROVIDED HEREIN, THERE ARE NO WARRANTIES,
         EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED
         WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

                                       7
<PAGE>

11.  LIMITATION OF LIABILITY.

     (a) DoubleTwist's sole liability to Hitachi for any claims, notwithstanding
         the form of such claims (e.g., contract, negligence or otherwise),
         arising out of errors or omissions in the Licensed Products shall be to
         furnish the correct information as soon as reasonably practicable.

     (b) DoubleTwist's sole liability for claims, notwithstanding the form of
         such claims (e.g., contract, negligence or otherwise), arising out of
         unavailability of support or the unusability of the Licensed Products
         shall be to use reasonable efforts to correct the Licensed Products as
         soon as reasonably practicable.

     (c) DoubleTwist shall not be liable or deemed to be in default for any
         delay or failure to perform under this Agreement resulting directly or
         indirectly from any cause beyond DoubleTwist's reasonable control such
         as acts of Gods, act of any governmental authority, riot, revolution,
         fires or war.

     (d) EXCEPT ANY CAUSE COVERED BY PARAGRAPH 9, IN NO EVENT WILL DoubleTwist
         BE RESPONSIBLE FOR SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL
         DAMAGES WHATSOEVER (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF
         BUSINESS PROFITS, BUSINESS INTERRUPTION LOSS OF BUSINESS INFORMATION,
         OR ANY OTHER PECUNIARY LOSS) ARISING OUT OF THE SALE, USE OR INABILITY
         TO USE THE Hitachi/DT PRODUCTS, EVEN IF DoubleTwist HAS BEEN ADVISED OF
         THE POSSIBILITY OF SUCH DAMAGES.

12.  TERM. Except as otherwise provided herein, this Agreement shall commence on
     the date hereof and shall continue for a period from April 3, 2000 through
     December 31, 2000 (the "Initial Term"). After the Initial Term, this
     Agreement shall be automatically extended for consecutive one (1) year
     terms, subject to termination by either party to take effect at the end of
     the Initial Term or any renewal term upon at least Thirty (30) days prior
     to written notice.

13.  TERMINATION.

     (a) Notwithstanding anything to the contrary contained herein, either party
         may terminate this Agreement (1) upon any material breach by the other
         of its obligations under this Agreement, or (2) if the other party
         shall commit an act of bankruptcy or become insolvent, by sending such
         party written notice of termination which shall state the nature of the
         breach. Such notice shall be effective thirty (30) days following the
         date thereof, unless such breach shall have been remedied during such
         thirty-day period.

                                       8
<PAGE>

     (b) In addition, DoubleTwist may terminate this Agreement, and any license
         granted to an End User for whom the Distribution Fee has not been paid
         if Hitachi fails to pay DoubleTwist any Distribution Fees or taxes due
         hereunder.

     (c) The foregoing rights and remedies shall be cumulative and in addition
         to all other rights and remedies available to each party in law and in
         equity.

     (d) All licenses with End Users which are entered into due to Hitachi's
         distribution of the Hitachi/DT Products will continue in accordance
         with the terms and applicable period as provided in the applicable
         DoubleTwist Software License Agreement.

     (e) Notwithstanding anything to the contrary contained herein, the rights
         and obligations set forth in Paragraphs 5(g), 8,9 and 11 shall survive
         termination of this Agreement.

14.  MISCELLANEOUS TERMS.

     (a) Each party represents to the other that this Agreement has been
         exhausted and delivered by an authorized representative of such signing
         party.

     (b) The headings and captions to this Agreement are for reference only and
         are not to be construed in any way as terms hereof.

     (c) Unless otherwise stated, all notices required under this Agreement
         shall be in writing and served by Certified mail or Registered mail,
         return receipt requested, with a copy by first class mail or by
         personal services and shall be deemed to have been duly given when sent
         if mailed to the addressee or when received if hand delivered at the
         address designated below or such subsequent address as may be
         designated in writing by the respective party:

                 if to DoubleTwist:

                 DoubleTwist, Inc.
                 1999 Harrison Street, Suite 1100
                 Oakland, CA 94612
                 Attn:  Legal Counsel

                 if to Hitachi:

                 [Contract]
                 International Procurement Center, Procurement Dept.
                 Hitachi Ltd.,
                 6, Kanda-Surugadai 4-Chome, Chiyoda-ku, Tokyo, 101-8010 Japan
                 Attn:  Manager, International Procurement Center

                                       9
<PAGE>

                 [Delivery]
                 Purchasing Sect. Administration Dept.
                 Central Research Laboratory, Hitachi, Ltd.
                 1-280, Higashi-Koigakubo, Kokubunji-shi, Tokyo, 185-8601, Japan
                 Attn:  Manager, Purchasing Sect.

                 [Technical]
                 Bio Informatic Dept. Life Science Gr.
                 Hitachi, ltd.
                 1-280, Higashi-Koigakubo, Kokubunji-shi, Tokyo, 185-8601, Japan
                 Attn:  Manager, Bioinformatics Gr.

     (d) If any of the provisions of this Agreement are invalid, illegal or
         unenforceable under any applicable statute or rule of law, the
         validity, legality or enforceability of the remaining provisions shall
         not be affected or impaired thereby.

     (e) This Agreement shall be interpreted in accordance with the laws of the
         State of California, USA, as if entered into by California residents,
         without regard to its conflict of laws rules.

     (f) Except for assignment in conjunction with a change of control, this
         Agreement shall not be assigned by either party without the written
         consent of the other party. In event of assignment in conjunction with
         change of control, this Agreement will bind and insure to benefit of
         each party's permitted successors and assigns.

     (g) DoubleTwist shall obtain any and all export licenses and/or
         governmental approvals that may be required to export the Licensed
         Product to Japan. Hitachi agrees that the Licensed Product may be
         subject to restrictions under the export control laws and regulations
         of the United States of America, including but not limited to the U.S.
         Export Administration Act and the U.S. Export Administration
         Regulations. Hitachi agrees not to export or re-export, directly or
         indirectly, the Licensed Product in whole or in part without first
         obtaining any required license or other approval from the U.S.
         Department of Commerce or any other agency or department of the United
         States Government.

     (h) This Agreement is the entire agreement between the parties relating to
         the subject matter hereof and supersedes all prior understanding,
         writings, proposals, representations or communications, oral or
         written, of either party. This Agreement may be amended only by an
         instrument executed by the authorized representatives of both parties.

                                       10
<PAGE>

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
date first written above.

DoubleTwist, Inc.                          Hitachi, Ltd.

By: /s/                                    By: /s/
   --------------------------------           ----------------------------------
Title:                                     Title:
      -----------------------------              -------------------------------
Date:                                      Date:
     ------------------------------             --------------------------------

                                       11
<PAGE>

                                    EXHIBIT A

                         DESCRIPTION OF LICENSED PRODUCT

Clustering and Alignment Tools (CAT), version 3.5, including Serial d2, Serial
d2_cluster, CRAW and MAP, in object code form only, and current Documentation.

<PAGE>

                                    EXHIBIT B

                            DISTRIBUTION FEE SCHEDULE

Hitachi shall purchase for distribution to End Users six (6) software packages
comprising Licensed Product and Documentation during the Initial Term ("Initial
Distributed Product"). Hitachi shall pay to DoubleTwist One Million Five Hundred
Ninety Thousand Dollars (US$1,590,000) within thirty (30) day after Hitachi's
acceptance as set forth in Paragraph 4(a), which acceptance or rejection shall
in no event be later than May 15, 2000, in full payment of Distribution Fees for
Initial Distributed Product.

For each additional Licensed Product distributed by Hitachi ("Subsequent
Distributed Product"), Hitachi shall pay to DoubleTwist a Distribution Fee of
Two Hundred Sixty Five Thousand Dollars (US$265,000), which amount shall be due
and payable to DoubleTwist within thirty (30) days of distribution of Licensed
Product to End User.

Additionally, for each Licensed Product distributed to an End User by Hitachi,
in the event such End User desires to receive, and Hitachi agrees to perform,
maintenance for such Licensed Product for any term beyond one (1) year from the
Effective Date of the license between DoubleTwist and End User ("Extended
Maintenance"), such Extended Maintenance shall be performed by Hitachi on an
annual basis ("Extended Maintenance Period"), and for each such Extended
Maintenance Period Hitachi shall pay to DoubleTwist, within thirty (30) days of
the first day of any such Extended Maintenance Period. Twenty Five Thousand
Dollars (US$25,000).

Hitachi America, Ltd. ("HAL") will act as a disbursement agent of Hitachi.
Notices and invoices to HAL shall be delivered or addressed to:

         Hitachi America, Ltd.
         Procurement and Technical Service Division
         2000 Sierra Point Parkway
         Brisbane, CA 94005-1835
         Attn:  Purchasing Manager

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