LEASE AGREEMENT

         THIS  LEASE  AGREEMENT  is made  this 1st day of March,  2004,  between
ARE-1500 East Gude LLC, a Delaware limited liability company  ("Landlord"),  and
Calypte Biomedical Corporation, a Delaware corporation ("Tenant").

ADDRESS:     1500 East Gude Drive, Rockville, Maryland

PREMISES:    That portion of the Project, containing approximately 25,459
             rentable square feet, as determined by Landlord, as shown on
             EXHIBIT A.

PROJECT:     The real property on which the building (the "BUILDING") in which
             the Premises are located, together with all improvements thereon
             and appurtenances thereto as described on EXHIBIT B.

BASE RENT:   $33,945.33 per month       RENTABLE AREA OF PREMISES: 25,459 sq.ft.

RENTABLE AREA OF PROJECT: 45,989 sq.ft. TENANT'S SHARE OF OPERATING
                                        EXPENSES: 55.36%

SECURITY DEPOSIT: $150,000              COMMENCEMENT DATE: March 1, 2004

BASE RENT COMMENCEMENT DATE:  The date the bioMerieux Lease (as defined in
                              Section 1) is terminated.
                              ---------

RENT ADJUSTMENT PERCENTAGE:   3.5%

BASE TERM:   Beginning on the Base Rent Commencement Date and ending on
             February 28, 2009.

PERMITTED USE:  Research and  development  laboratory,  related
                office and other  related  uses  consistent  with the
                character of the Project and  otherwise in compliance
                with the provisions of Section 7 hereof.

ADDRESS FOR RENT PAYMENT:                    LANDLORD'S NOTICE ADDRESS:
135 N. Los Robles Avenue, Suite 250          135 N. Los Robles Avenue, Suite 250
Pasadena, CA 91101                           Pasadena, CA 91101
Attention: Accounts Receivable               Attention: Corporate Secretary

TENANT'S NOTICE ADDRESS:
1265 Harbor Bay Parkway
Alameda, California  94502
Attention:  Corporate Secretary

The following  Exhibits and Addenda are attached hereto and incorporated  herein
by this reference:

[X] EXHIBIT A - PREMISES  DESCRIPTION [X] EXHIBIT B - DESCRIPTION OF PROJECT [X]
EXHIBIT C - WORK LETTER [ ] EXHIBIT D - COMMENCEMENT  DATE [X] EXHIBIT E - RULES
AND REGULATIONS [X] EXHIBIT F - TENANT'S PERSONAL PROPERTY

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 2

     1. LEASE OF PREMISES.  Upon and subject to all of the terms and  conditions
hereof,  Landlord  hereby leases the Premises to Tenant and Tenant hereby leases
the Premises from Landlord  effective as of the Base Rent Commencement Date. The
portions of the Project  which are for the  non-exclusive  use of tenants of the
Project are  collectively  referred to herein as the  "COMMON  AREAS."  Landlord
reserves the right to modify Common Areas,  provided that such  modifications do
not materially  adversely  affect Tenant's use of the Premises for the Permitted
Use.

     2. DELIVERY; ACCEPTANCE OF PREMISES; COMMENCEMENT DATE. Tenant shall accept
delivery of the Premises on the Base Rent  Commencement  Date. The "COMMENCEMENT
DATE"  shall be the date of this  Lease.  The "TERM" of this Lease  shall be the
Base Term, as defined above on the first page of this Lease. Landlord shall have
no obligation for any defects in the Premises; and Tenant's taking possession of
the Premises on the Base Rent  Commencement  Date shall be  conclusive  evidence
that Tenant accepts the Premises and that the Premises were in good condition at
the time  possession  was taken.  Tenant  agrees and  acknowledges  that neither
Landlord nor any agent of Landlord has made any  representation or warranty with
respect to the  condition  of all or any portion of the Premises or the Project,
and/or  the  suitability  of the  Premises  or the  Project  for the  conduct of
Tenant's  business,  and Tenant waives any implied warranty that the Premises or
the Project are suitable  for the  Permitted  Use.  This Lease  constitutes  the
complete  agreement of Landlord  and Tenant with  respect to the subject  matter
hereof and supersedes any and all prior representations,  inducements, promises,
agreements,  understandings  and  negotiations  which are not contained  herein.
Landlord  in   executing   this  Lease  does  so  in  reliance   upon   Tenant's
representations, warranties, acknowledgments and agreements contained herein.

     BIOMERIEUX LEASE.  Landlord and Tenant hereby acknowledge that the Premises
are  presently  leased by  Landlord to  bioMerieux  Vitek,  Inc.  ("BIOMERIEUX")
pursuant to that certain  Lease  Agreement  dated as of October 22, 1996, by and
between bioMerieux and Landlord's predecessor-in-interest in the Project, Aquila
Biopharmaceuticals,  as amended by that certain First Amendment to Lease,  dated
October 2, 1997, and that certain Second Amendment to Lease,  dated December 21,
2001 (herein collectively, the "BIOMERIEUX LEASE"), and that Tenant presently is
in possession of the Premises  pursuant to a Sublease  dated December 1998 (such
Sublease,  as the same may be amended from time to time,  is herein the "CALYPTE
SUBLEASE").  The  parties  further  hereby  acknowledge  and agree that  nothing
contained in this Lease shall be deemed to or interpreted  as,  affecting in any
way  either  the terms and  conditions  of the  bioMerieux  Lease,  or  Tenant's
obligations under the Calypte  Sublease.  Tenant recognizes that its obligations
hereunder  regarding the payment of Additional  Rent shall be  independent  from
Tenant's right of possession of the Premises under this Lease.

     3. RENT.

     (a) BASE  RENT.  No later  than  fifteen  (15) days  prior to the Base Rent
Commencement  Date,  Tenant shall pay to Landlord,  the first month's Base Rent.
Tenant shall pay to Landlord in advance, without demand, abatement, deduction or
set-off,  monthly  installments  of Base Rent on or before the first day of each
calendar month during the Term hereof, after the Base Rent Commencement Date, in
lawful  money of the United  States of America,  at the office of  Landlord  for
payment of Rent set forth above,  or to such other person or at such other place
as Landlord may from time to time  designate  in writing.  Payments of Base Rent
for any fractional calendar month shall be prorated. The obligation of Tenant to
pay Base Rent and other sums to Landlord and the  obligations  of Landlord under
this Lease are independent  obligations.  Tenant shall have no right at any time
to abate,  reduce,  or set-off any Rent (as defined in Section 5) due  hereunder
except for any abatement as may be expressly provided in this Lease.

     (b)  ADDITIONAL  RENT.  In addition to Base Rent,  Tenant  agrees to pay to
Landlord  as  additional  rent  ("ADDITIONAL  RENT"):  (x)  from and  after  the
Commencement  Date through the  remainder of the Term, an amount equal to $.2585
per annum for each dollar or portion thereof of the Tenant Improvement Allowance
elected to be used by Tenant  pursuant to Section 5(b) of the Work  Letter;  and
                                          ------------
(y) from and  after the Base  Rent  Commencement  Date,  (i)  Tenant's  Share of
"Operating  Expenses"  (as  defined  in  Section  5), and (ii) any and all other
                                         ----------
amounts  Tenant  assumes or agrees to pay under the

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provisions of this Lease, including,  without limitation, any and all other sums
that may become due by reason of any default of Tenant or failure to comply with
the agreements, terms, covenants and conditions of this Lease to be performed by
Tenant, after any applicable notice and cure period.

     4. BASE RENT  ADJUSTMENTS.  Base Rent  shall be  increased  on each  annual
anniversary  of the first day of the first  full  month  during the Term of this
Lease  (each  an  "ADJUSTMENT  DATE")  by  multiplying  the  Base  Rent  payable
immediately  before such Adjustment  Date by the Rent Adjustment  Percentage and
adding the  resulting  amount to the Base Rent payable  immediately  before such
Adjustment Date. Base Rent, as so adjusted,  shall thereafter be due as provided
herein.  Base  Rent  adjustments  for any  fractional  calendar  month  shall be
prorated.

     5. OPERATING EXPENSE  PAYMENTS.  Landlord shall deliver to Tenant a written
estimate  of  Operating  Expenses  for each  calendar  year during the Term (the
"ANNUAL  ESTIMATE"),  which may be revised by Landlord  from time to time during
such  calendar  year.  During each month of the Term, on the same date that Base
Rent is due,  Tenant  shall pay  Landlord an amount  equal to 1/12th of Tenant's
Share of the Annual Estimate.  Payments for any fractional  calendar month shall
be prorated.

     The term  "OPERATING  EXPENSES" means all costs and expenses of any kind or
description  whatsoever  incurred or accrued each calendar year by Landlord with
respect to the Project  (including,  without  duplication,  Taxes (as defined in
Section 9),  reasonable  reserves  consistent  with good  business  practice for
future repairs and replacements, capital repairs and improvements amortized over
the lesser of 7 years and the useful life of such capital  items,  and the costs
of  Landlord's  third  party  property  manager  or, if there is no third  party
property  manager,  administration  rent in the  amount  of 5.0% of Base  Rent),
excluding only:

     (a) the original  construction costs of the Project and renovation prior to
the  date of the  Lease  and  costs  of  correcting  defects  in  such  original
construction or renovation;

     (b) capital expenditures for expansion of the Project;

     (c)  interest,  principal  payments of Mortgage  (as defined in Section 27)
debts of  Landlord,  financing  costs  and  amortization  of funds  borrowed  by
Landlord,  whether  secured or unsecured  and all payments of base rent (but not
taxes or operating expenses) under any ground lease or other underlying lease of
all or any portion of the Project;

     (d) depreciation of the Project (except for capital improvements,  the cost
of which are includable in Operating Expenses);

     (e) advertising,  legal and space planning expenses and leasing commissions
and other costs and expenses  incurred in procuring and leasing space to tenants
for the Project,  including any leasing office  maintained in the Project,  free
rent and construction allowances for tenants;

     (f) legal and other expenses  incurred in the negotiation or enforcement of
leases;

     (g) completing, fixturing, improving, renovating, painting, redecorating or
other work,  which  Landlord pays for or performs for other tenants within their
premises, and costs of correcting defects in such work;

     (h) costs of utilities outside normal business hours sold to tenants of the
Project;

     (i) costs to be  reimbursed  by other tenants of the Project or Taxes to be
paid directly by Tenant or other tenants of the Project, whether or not actually
paid;

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 4

     (j) salaries,  wages,  benefits and other compensation paid to officers and
employees of Landlord who are not assigned in whole or in part to the operation,
management, maintenance or repair of the Project;

     (k) general  organizational,  administrative and overhead costs relating to
maintaining Landlord`s existence, either as a corporation, partnership, or other
entity, including general corporate, legal and accounting expenses;

     (l) costs (including attorneys' fees and costs of settlement, judgments and
payments in lieu  thereof)  incurred in  connection  with disputes with tenants,
other occupants, or prospective tenants, and costs and expenses, including legal
fees,  incurred in connection  with  negotiations  or disputes  with  employees,
consultants,  management agents, leasing agents, purchasers or mortgagees of the
Building;

     (m) costs  incurred by  Landlord  due to the  violation  by  Landlord,  its
employees,  agents or  contractors  or any tenant of the terms and conditions of
any  lease of space in the  Project  or any Legal  Requirement  (as  defined  in
Section 7);

     (n)  penalties,  fines  or  interest  incurred  as a result  of  Landlord`s
inability  or  failure  to make  payment  of  Taxes  and/or  to file  any tax or
informational returns when due, or from Landlord<<`s failure to make any payment
of Taxes required to be made by Landlord hereunder before delinquency;

     (o) overhead and profit  increment paid to Landlord or to  subsidiaries  or
affiliates  of Landlord  for goods  and/or  services in or to the Project to the
extent the same  exceeds  the costs of such goods  and/or  services  rendered by
unaffiliated third parties on a competitive basis;

(p) costs of Landlord's  charitable or political  contributions,  or of fine art
maintained at the Project;

     (q) costs in connection  with services  (including  electricity),  items or
other  benefits of a type which are not  standard  for the Project and which are
not  available  to  Tenant  without  specific  charges  therefor,  but which are
provided to another tenant or occupant of the Project, whether or not such other
tenant or occupant is specifically charged therefor by Landlord;

     (r) costs incurred in the sale or refinancing of the Project;

     (s) net  income  taxes of  Landlord  or the  owner of any  interest  in the
Project,  franchise,  capital stock,  gift,  estate or inheritance  taxes or any
federal,  state or local  documentary  taxes imposed  against the Project or any
portion thereof or interest therein; and

     (t) any expenses  otherwise  includable  within  Operating  Expenses to the
extent  actually  reimbursed  by persons other than tenants of the Project under
leases for space in the Project.

     Within 90 days after the end of each  calendar  year (or such longer period
as may be reasonably required), Landlord shall furnish to Tenant a statement (an
"ANNUAL  STATEMENT")  showing in reasonable  detail:  (a) the total and Tenant's
Share of actual Operating  Expenses for the previous  calendar year, and (b) the
total of Tenant's  payments in respect of Operating  Expenses for such year.  If
Tenant's  Share of actual  Operating  Expenses  for such year  exceeds  Tenant's
payments  of  Operating  Expenses  for such year,  the  excess  shall be due and
payable by Tenant as Rent within 30 days after delivery of such Annual Statement
to Tenant.  If Tenant's  payments  of  Operating  Expenses  for such year exceed
Tenant's Share of actual Operating Expenses for such year Landlord shall pay the
excess to Tenant within 30 days after delivery of such Annual Statement,  except
that after the  expiration,  or earlier  termination of the Term or if Tenant is
delinquent  in its  obligation  to pay Rent,  Landlord  shall pay the  excess to
Tenant after deducting all other amounts due Landlord.

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 5

     The Annual  Statement shall be final and binding upon Tenant unless Tenant,
within 30 days after Tenant's receipt thereof, shall contest any item therein by
giving written notice to Landlord, specifying each item contested and the reason
therefor. Operating Expenses for the calendar years in which Tenant's obligation
to share therein begins and ends shall be prorated. Notwithstanding anything set
forth  herein to the  contrary,  if the Project is not at least 95%  occupied on
average during any year of the Term,  Tenant's  Share of Operating  Expenses for
such year shall be  computed  as though the  Project  had been 95%  occupied  on
average during such year.

     "TENANT'S  SHARE"  shall be the  percentage  set forth on the first page of
this Lease as Tenant's Share. Landlord may equitably increase Tenant's Share for
any item of expense or cost  reimbursable  by Tenant  that  relates to a repair,
replacement, or service that benefits only the Premises or only a portion of the
Project that  includes the Premises or that varies with  occupancy or use.  Base
Rent,  Tenant's  Share of Operating  Expenses and all other  amounts  payable by
Tenant to Landlord hereunder are collectively referred to herein as "RENT."

     6. SECURITY DEPOSIT. Tenant shall deposit with Landlord, a security deposit
(the  "SECURITY  DEPOSIT") for the  performance  of all of Tenant's  obligations
hereunder.  The  Security  Deposit  shall be paid in two (2)  increments.  On or
before the Commencement  Date, Tenant shall deposit with Landlord,  a portion of
the Security  Deposit in an amount  equal to $50,000,  and no later than fifteen
(15) days prior to the Base Rent  Commencement  Date,  Tenant shall deposit with
Landlord the  remaining  portion of the  Security  Deposit in an amount equal to
$100,000.  The Security  Deposit  shall be in the form of an  unconditional  and
irrevocable letter of credit (the "LETTER OF CREDIT"): (i) in form and substance
satisfactory to Landlord,  (ii) naming Landlord as beneficiary,  (iii) expressly
allowing Landlord to draw upon it at any time from time to time by delivering to
the issuer notice that Landlord is entitled to draw  thereunder,  (iv) issued by
an  FDIC-insured  financial  institution   satisfactory  to  Landlord,  and  (v)
redeemable by presentation  of a sight draft in the state of Landlord's  choice.
If Tenant does not provide Landlord with a substitute Letter of Credit complying
with  all of the  requirements  hereof  at  least  10  days  before  the  stated
expiration  date of any then current  Letter of Credit,  Landlord shall have the
right to draw the full amount of the current Letter of Credit and hold the funds
drawn in cash without  obligation for interest thereon as the Security  Deposit.
The Security  Deposit shall be held by Landlord as security for the  performance
of Tenant's obligations under this Lease. The Security Deposit is not an advance
rental deposit or a measure of Landlord's  damages in case of Tenant's  default.
Upon each  occurrence of a Default (as defined in Section 20),  Landlord may use
all or any part of the  Security  Deposit to pay  delinquent  payments due under
this Lease, and the cost of any damage,  injury,  expense or liability caused by
such Default,  without prejudice to any other remedy provided herein or provided
by law. Upon any such use of all or any portion of the Security Deposit,  Tenant
shall pay Landlord on demand the amount that will  restore the Security  Deposit
to the amount required under this Section 5. Tenant hereby waives the provisions
of any law,  now or hereafter in force,  which  provide that  Landlord may claim
from a security deposit only those sums reasonably  necessary to remedy defaults
in the  payment  of Rent,  to  repair  damage  caused  by Tenant or to clean the
Premises,  it being  agreed that  Landlord  may, in  addition,  claim those sums
reasonably  necessary  to  compensate  Landlord  for any other  loss or  damage,
foreseeable  or  unforeseeable,  caused by the act or  omission of Tenant or any
officer,  employee,  agent  or  invitee  of  Tenant.  Upon  bankruptcy  or other
debtor-creditor proceedings against Tenant, the Security Deposit shall be deemed
to be applied  first to the payment of Rent and other  charges due  Landlord for
periods prior to the filing of such proceedings. Upon any such use of all or any
portion of the Security Deposit,  Tenant shall,  within 5 days after demand from
Landlord, restore the Security Deposit to the amount required in this Section 5.
If Tenant shall fully perform  every  provision of this Lease to be performed by
Tenant,  the Security  Deposit,  or any balance  thereof (i.e.,  after deducting
therefrom all amounts to which Landlord is entitled under the provisions of this
Lease),  shall be  returned to Tenant (or,  at  Landlord's  option,  to the last
assignee of Tenant's interest  hereunder) within 90 days after the expiration or
earlier termination of this Lease.

     If Landlord  transfers its interest in the Project or this Lease,  Landlord
shall either (a) transfer any Security Deposit then held by Landlord to a person
or entity assuming Landlord's obligations under this Section 6, or (b) return to
Tenant any  Security  Deposit  then held by  Landlord  and  remaining  after the
deductions permitted herein. Upon such transfer to such transferee or the return
of the Security  Deposit

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to  Tenant,  Landlord  shall  have no  further  obligation  with  respect to the
Security Deposit, and Tenant's right to the return of the Security Deposit shall
apply solely  against  Landlord's  transferee.  The  Security  Deposit is not an
advance  rental  deposit or a measure of Landlord's  damages in case of Tenant's
default.  Landlord's  obligation  respecting  the Security  Deposit is that of a
debtor, not a trustee, and no interest shall accrue thereon.

     7. USE. The Premises  shall be used solely for the  Permitted Use set forth
in the basic lease  provisions on page 1 of this Lease,  and in compliance  with
all  laws,  orders,  judgments,  ordinances,   regulations,  codes,  directives,
permits, licenses, covenants and restrictions now or hereafter applicable to the
Premises, and to the use and occupancy thereof,  including,  without limitation,
the Americans With Disabilities Act, 42 U.S.C. ss. 12101, et seq. (together with
the regulations  promulgated  pursuant  thereto,  "ADA")  (collectively,  "LEGAL
REQUIREMENTS"  and each,  a "LEGAL  REQUIREMENT").  Tenant  shall,  upon 5 days'
written  notice from  Landlord,  discontinue  any use of the  Premises  which is
declared  by any  Governmental  Authority  (as  defined  in  Section  9)  having
                                                             ----------
jurisdiction  to be a violation of a Legal  Requirement.  Tenant will not use or
permit the  Premises to be used for any purpose or in any manner that would void
Tenant's or  Landlord's  insurance,  increase the  insurance  risk, or cause the
disallowance of any sprinkler or other credits. Tenant shall not permit any part
of the Premises to be used as a "place of public  accommodation",  as defined in
the ADA or any  similar  legal  requirement.  Tenant  shall  reimburse  Landlord
promptly upon demand for any additional  premium  charged for any such insurance
policy by reason of  Tenant's  failure  to comply  with the  provisions  of this
Section or otherwise  caused by Tenant's use and/or  occupancy of the  Premises.
Tenant will use the Premises in a careful,  safe and proper  manner and will not
commit or permit waste, overload the floor or structure of the Premises, subject
the Premises to use that would damage the Premises or obstruct or interfere with
the rights of Landlord or other  tenants or occupants of the Project,  including
conducting  or  giving  notice  of any  auction,  liquidation,  or going  out of
business sale on the Premises,  or using or allowing the Premises to be used for
any  unlawful  purpose.  Tenant  shall cause any  equipment  or  machinery to be
installed in the Premises so as to reasonably  prevent sounds or vibrations from
the Premises from  extending  into Common Areas,  or other space in the Project.
Tenant shall not place any machinery or equipment weighing 500 pounds or more in
or upon the Premises or transport or move such items through the Common Areas of
the Project or in the Project  elevators  without the prior  written  consent of
Landlord.  Except as may be provided  under the Work  Letter,  Tenant shall not,
without the prior  written  consent of Landlord,  use the Premises in any manner
which will require ventilation,  air exchange,  heating, gas, steam, electricity
or  water  beyond  the  existing  capacity  of the  Project  as  proportionately
allocated to the Premises based upon Tenant's Share as usually furnished for the
Permitted Use.

     Tenant, at its sole expense, shall make any alterations or modifications to
the interior or the exterior of the Premises or the Project that are required by
Legal  Requirements  related  to  Tenant's  use or  occupancy  of the  Premises.
Notwithstanding  any other  provision  herein to the  contrary,  Tenant shall be
responsible  for  any and  all  demands,  claims,  liabilities,  losses,  costs,
expenses,  actions,  causes of action, damages or judgments,  and all reasonable
expenses  incurred in investigating  or resisting the same  (including,  without
limitation,  reasonable  attorneys' fees, charges and disbursements and costs of
suit)  (collectively,  "CLAIMS")  arising  out of or in  connection  with  Legal
Requirements,  and  Tenant  shall  indemnify,  defend,  hold and  save  Landlord
harmless  from and  against any and all Claims  arising out of or in  connection
with any failure of the Premises to comply with any Legal Requirement.

     8. HOLDING  OVER.  If, with  Landlord's  express  written  consent,  Tenant
retains possession of the Premises after the termination of the Term, (i) unless
otherwise  agreed in such written  consent,  such possession shall be subject to
immediate  termination by Landlord at any time,  (ii) all of the other terms and
provisions of this Lease (including,  without limitation, the adjustment of Base
Rent  pursuant  to  Section 4 hereof)  shall  remain  in full  force and  effect
                    ---------
(excluding  any  expansion or renewal  option or other  similar right or option)
during such holdover period, (iii) Tenant shall continue to pay Base Rent in the
amount  payable upon the date of the  expiration or earlier  termination of this
Lease or such other  amount as Landlord may  indicate,  in  Landlord's  sole and
absolute discretion,  in such written consent, and (iv) all other payments shall
continue  under the terms of this Lease.  If Tenant remains in possession of the
Premises  after the  expiration or earlier  termination  of the Term without the
express  written  consent  of  Landlord,  (A)  Tenant  shall  become a tenant at
sufferance  upon the terms of this Lease except that the

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monthly  rental shall be equal to 200% of Rent in effect during the last 30 days
of the Term, and (B) Tenant shall be responsible for all actual damages suffered
by Landlord  resulting  from  Tenant's  holding over. No holding over by Tenant,
whether with or without consent of Landlord,  shall operate to extend this Lease
except  as  otherwise  expressly  provided,  and  this  Section  8 shall  not be
construed as consent for Tenant to retain possession of the Premises. Acceptance
by Landlord of Rent after the  expiration of the Term or earlier  termination of
this Lease shall not result in a renewal or reinstatement of this Lease.

     9. TAXES.  Landlord  shall pay, as part of Operating  Expenses,  all taxes,
levies,  assessments and governmental charges of any kind (collectively referred
to as "TAXES")  imposed by any federal,  state,  regional,  municipal,  local or
other  governmental   authority  or  agency,   including,   without  limitation,
quasi-public agencies (collectively,  "GOVERNMENTAL AUTHORITY") during the Term,
including,  without  limitation,  all Taxes:  (i)  imposed on or  measured by or
based,  in whole or in part, on rent payable to Landlord under this Lease and/or
from the rental by Landlord of the Project or any portion thereof, or (ii) based
on the square footage, assessed value or other measure or evaluation of any kind
of the  Premises  or the  Project,  or (iii)  assessed  or  imposed by or on the
operation  or  maintenance  of any  portion  of  the  Premises  or the  Project,
including  parking,  or (iv)  assessed or imposed by, or at the direction of, or
resulting from statutes or regulations, or interpretations thereof,  promulgated
by,  any  Governmental  Authority,  or (v)  imposed as a license or other fee on
Landlord's  business of leasing  space in the  Project.  Landlord may contest by
appropriate legal proceedings the amount,  validity, or application of any Taxes
or liens securing Taxes. Taxes shall not include any net income taxes imposed on
Landlord unless such net income taxes are in substitution  for any Taxes payable
hereunder.  If any such Tax is levied or assessed directly against Tenant,  then
Tenant shall be responsible for and shall pay the same at such times and in such
manner as the  taxing  authority  shall  require.  Tenant  shall  pay,  prior to
delinquency,  any and all Taxes levied or assessed against any personal property
or trade fixtures  placed by Tenant in the Premises,  whether levied or assessed
against Landlord or Tenant.  If any Taxes on Tenant's personal property or trade
fixtures are levied against Landlord or Landlord's property,  or if the assessed
valuation of the Project is increased by a value attributable to improvements in
or alterations to the Premises,  whether owned by Landlord or Tenant and whether
or not affixed to the real property so as to become a part thereof,  higher than
the base valuation on which Landlord from  time-to-time  allocates  Taxes to all
tenants in the Project,  Landlord shall have the right,  but not the obligation,
to pay such Taxes.  Landlord's  determination  of any excess assessed  valuation
shall be binding and conclusive,  absent manifest error.  The amount of any such
payment by Landlord shall constitute Additional Rent due from Tenant to Landlord
immediately upon demand.

     10. PARKING.  Subject to all matters of record, Force Majeure, a Taking (as
defined  in  Section  19 below)  and the  exercise  by  Landlord  of its  rights
hereunder,  Tenant  shall have the right,  in common  with other  tenants of the
Project pro rata in  accordance  with the rentable  area of the Premises and the
rentable areas of the Project  occupied by such other tenants,  to park in those
areas  designated for non-reserved  parking,  subject in each case to Landlord's
rules and  regulations.  Landlord may allocate  parking  spaces among Tenant and
other tenants in the Project pro rata as described above if Landlord  determines
that  such  parking  facilities  are  becoming  crowded.  Landlord  shall not be
responsible  for enforcing  Tenant's  parking  rights against any third parties,
including other tenants of the Project.

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     11. UTILITIES, SERVICES.

     Landlord  shall  provide,  subject to the terms of this Section 11,  water,
                                                             ----------
electricity,   heat,  light,  power,  telephone,   sewer,  and  other  utilities
(including gas and fire sprinklers to the extent the Project is plumbed for such
services) (collectively, "UTILITIES"). Landlord shall pay, as Operating Expenses
or subject to Tenant's reimbursement  obligation,  for all Utilities used on the
Premises, all maintenance charges for Utilities,  and any storm sewer charges or
other similar  charges for Utilities  imposed by any  Governmental  Authority or
Utility  provider,  and any taxes,  penalties,  surcharges  or  similar  charges
thereon. Landlord may cause, at Tenant's expense, any Utilities to be separately
metered or charged directly to Tenant by the provider. Tenant shall pay directly
to the Utility provider, prior to delinquency,  any separately metered Utilities
and services  which may be furnished to Tenant or the Premises  during the Term.
Tenant  shall pay, as part of Operating  Expenses,  its share of all charges for
jointly metered  Utilities based upon consumption,  as reasonably  determined by
Landlord.  No  interruption or failure of Utilities,  from any cause  whatsoever
other  than  Landlord's  willful   misconduct,   shall  result  in  eviction  or
constructive  eviction of Tenant,  termination of this Lease or the abatement of
Rent. Tenant agrees to limit use of water and sewer with respect to Common Areas
to normal restroom use.

     12.  ALTERATIONS AND TENANT'S  PROPERTY.  Any  alterations,  additions,  or
improvements  made  to  the  Premises  by  or on  behalf  of  Tenant,  including
additional locks or bolts of any kind or nature upon any doors or windows in the
Premises,  but  excluding  installation,  removal or  realignment  of  furniture
systems (other than removal of furniture  systems owned or paid for by Landlord)
not involving any  modifications to the structure or connections  (other then by
ordinary  plugs or jacks)  to  Building  Systems  (as  defined  in  Section  13)
                                                                    -----------
("ALTERATIONS") shall be subject to Landlord's prior written consent,  which may
be given or  withheld  in  Landlord's  sole  discretion  if any such  Alteration
affects the structure or Building Systems. If Landlord approves any Alterations,
Landlord  may  impose  such   conditions  on  Tenant  in  connection   with  the
commencement,  performance  and  completion of such  Alterations as Landlord may
deem  appropriate in Landlord's  sole and absolute  discretion.  Any request for
approval  shall be in  writing,  delivered  not less  than 10  business  days in
advance of any proposed construction,  and accompanied by plans, specifications,
bid proposals,  work contracts and such other information  concerning the nature
and  cost  of the  alterations  as  may be  reasonably  requested  by  Landlord,
including the identities and mailing addresses of all persons performing work or
supplying materials.  Landlord's right to review plans and specifications and to
monitor  construction  shall be solely for its own benefit,  and Landlord  shall
have no duty to ensure that such plans and specifications or construction comply
with  applicable  Legal  Requirements.  Tenant shall cause, at its sole cost and
expense,  all Alterations to comply with insurance  requirements  and with Legal
Requirements  and shall implement at its sole cost and expense any alteration or
modification  required  by Legal  Requirements  as a result of any  Alterations.
Tenant shall pay to Landlord,  as Additional  Rent, on demand an amount equal to
5% of all charges  incurred by Tenant or its contractors or agents in connection
with any Alteration to cover  Landlord's  overhead and expenses for plan review,
coordination,  scheduling and supervision.  Before Tenant begins any Alteration,
Landlord  may post on and  about  the  Premises  notices  of  non-responsibility
pursuant to applicable law.  Tenant shall reimburse  Landlord for, and indemnify
and hold Landlord  harmless from, any expense  incurred by Landlord by reason of
faulty work done by Tenant or its  contractors,  delays  caused by such work, or
inadequate cleanup.

     Tenant shall furnish  security or make other  arrangements  satisfactory to
Landlord to assure payment for the completion of all  Alterations  work free and
clear of liens, and shall provide (and cause each contractor or subcontractor to
provide)  certificates of insurance for workers' compensation and other coverage
in amounts and from an insurance  company  satisfactory  to Landlord  protecting
Landlord  against  liability  for  personal  injury or  property  damage  during
construction.  Upon  completion  of any  Alterations,  Tenant  shall  deliver to
Landlord:  (i) sworn  statements  setting forth the names of all contractors and
subcontractors who did the work and final lien waivers from all such contractors
and subcontractors; and (ii) "as built" plans for any such Alteration.

     Other than (i) the items, if any, listed on EXHIBIT F attached hereto, (ii)
any items  agreed by  Landlord  in  writing to be  included  on EXHIBIT F in the
future,  and (iii) any trade fixtures,  machinery,  equipment and other personal
property not paid for out of the TI Fund (as defined in the Work  Letter)

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which may be removed without material damage to the Premises, which damage shall
be repaired  (including capping or terminating utility hook-ups behind walls) by
Tenant during the Term (collectively,  "TENANT'S PROPERTY"), all property of any
kind  paid for  with  the TI Fund,  all  Alterations,  real  property  fixtures,
built-in  machinery  and  equipment,  built-in  casework  and cabinets and other
similar  additions and  improvements  built into the Premises so as to become an
integral  part of the Premises  such as fume hoods which  penetrate  the roof or
plenum  area,  built-in  cold rooms,  built-in  warm rooms,  walk-in cold rooms,
walk-in  warm  rooms,   deionized  water  systems,   glass  washing   equipment,
autoclaves, chillers, built-in plumbing, electrical and mechanical equipment and
systems,   and  any  power   generator   and  transfer   switch   (collectively,
"INSTALLATIONS")  shall be and shall remain the property of Landlord  during the
Term and following the expiration or earlier  termination of the Term, shall not
be removed by Tenant at any time  during the Term and shall  remain  upon and be
surrendered  with the Premises as a part thereof in  accordance  with Section 28
                                                                      ----------
following  the  expiration  or  earlier  termination  of this  Lease;  provided,
                                                                       --------
however,  that Landlord shall, at the time its approval of such  Installation is
-------
requested  notify  Tenant if it has  elected  to cause  Tenant  to  remove  such
Installation  upon the  expiration  or earlier  termination  of this  Lease.  If
Landlord so elects, Tenant shall remove such Installation upon the expiration or
earlier termination of this Lease and restore any damage caused by or occasioned
as a result of such removal,  including,  when removing any of Tenant's Property
which was plumbed,  wired or otherwise connected to any of the Building Systems,
capping off all such connections  behind the walls of the Premises and repairing
any holes. During any such restoration period, Tenant shall pay Rent to Landlord
as provided herein as if said space were otherwise occupied by Tenant.

     13. LANDLORD'S REPAIRS.  Landlord, as an Operating Expense,  shall maintain
all of the  structural,  exterior,  parking,  roof,  the common  lobby and other
Common Areas of the Project,  including  the  sprinkler  systems and fire alarms
("BUILDING  SYSTEMS"),  in good repair,  reasonable  wear and tear and uninsured
losses and damages  caused by Tenant,  or by any of Tenant's  agents,  servants,
employees,  invitees and contractors (collectively,  "TENANT Parties") excluded.
Losses and  damages  caused by Tenant or any Tenant  Party  shall be repaired by
Landlord,  to the extent not covered by  insurance,  at  Tenant's  sole cost and
expense.  Landlord  reserves the right to stop  Building  Systems  services when
necessary (i) by reason of accident or emergency,  or (ii) for planned  repairs,
alterations or improvements,  which are, in the judgment of Landlord,  desirable
or necessary to be made, until said repairs,  alterations or improvements  shall
have been  completed.  Landlord  shall have no  responsibility  or liability for
failure  to  supply  Building   Systems  services  during  any  such  period  of
interruption;  provided,  however,  that  Landlord  shall,  except  in  case  of
emergency, make a commercially reasonable effort to give Tenant 24 hours advance
notice  of any  planned  stoppage  of  Building  Systems  services  for  routine
maintenance,  repairs,  alterations or improvements.  Tenant shall promptly give
Landlord  written  notice of any repair  required by  Landlord  pursuant to this
Section,  after which Landlord shall make a  commercially  reasonable  effort to
promptly  effect such  repair.  Landlord  shall not be liable for any failure to
make any repairs or to perform any maintenance unless such failure shall persist
for an unreasonable  time after Tenant's  initial written notice of the need for
such repairs or  maintenance.  Tenant waives its rights under any state or local
law to terminate  this Lease or to make such repairs at  Landlord's  expense and
agrees that the parties' respective rights with respect to such matters shall be
solely as set forth herein.  Repairs required as the result of fire, earthquake,
flood,  vandalism,  war,  or  similar  cause of damage or  destruction  shall be
controlled by Section 18.
              ----------

14.  TENANT'S  REPAIRS.  Subject to Section 13 hereof,  Tenant,  at its expense,
                                    ----------
shall  repair,  replace  and  maintain  in good  condition  all  portions of the
Premises,  including,  without limitation,  entries,  doors, ceilings,  interior
windows,  interior walls, the interior side of demising walls, and the elevator,
and all  equipment  located on the roof of the Building  servicing the Premises.
Such repair and replacement may include capital  expenditures  and repairs whose
benefit may extend  beyond the Term.  Tenant shall  maintain at all times during
the Term, at its sole cost and expense, with qualified  contractors  maintenance
and repair  contracts  in form and content  satisfactory  to  Landlord,  for the
elevator and all equipment  located on the roof (the  "MAINTENANCE  CONTRACTS").
Landlord shall be a third party beneficiary of such Maintenance  Contracts,  and
Tenant  shall  deliver  copies of the  Maintenance  Contracts  to Landlord on or
before the Base Rent  Commencement  Date.  Should  Tenant  fail to make any such
repair or  replacement  or fail to maintain the  Premises,  Landlord  shall give
Tenant notice of such failure.  If Tenant fails to commence cure of such failure
within 10 days of Landlord's  notice, and thereafter  diligently  prosecute

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such cure to completion,  Landlord may perform such work and shall be reimbursed
by Tenant within 10 days after demand therefor;  provided, however, that if such
failure by Tenant creates or could create an emergency, Landlord may immediately
commence  cure of such failure and shall  thereafter  be entitled to recover the
costs of such cure from Tenant. Subject to Sections 17 and 18, Tenant shall bear
                                           -----------     --
the full  uninsured cost of any repair or replacement to any part of the Project
that  results  from damage  caused by Tenant or any Tenant  Party and any repair
that benefits only the Premises.

     15. MECHANIC'S  LIENS.  Tenant shall discharge,  by bond or otherwise,  any
mechanic's  lien filed  against  the  Premises  or against  the Project for work
claimed to have been done for, or materials  claimed to have been  furnished to,
Tenant within 30 days after the filing thereof,  at Tenant's sole cost and shall
otherwise  keep the Premises and the Project free from any liens  arising out of
work performed,  materials furnished or obligations  incurred by Tenant.  Should
Tenant fail to discharge  any lien  described  herein,  Landlord  shall have the
right,  but not the  obligation,  to pay such claim or post a bond or  otherwise
provide  security to eliminate  the lien as a claim against title to the Project
and the cost thereof shall be immediately due from Tenant as Additional Rent. If
Tenant shall lease or finance the acquisition of office equipment,  furnishings,
or other  personal  property  of a  removable  nature  utilized by Tenant in the
operation of Tenant's business, Tenant warrants that any Uniform Commercial Code
Financing Statement filed as a matter of public record by any lessor or creditor
of Tenant will upon its face or by exhibit thereto  indicate that such Financing
Statement is applicable  only to removable  personal  property of Tenant located
within the  Premises.  In no event shall the address of the Project be furnished
on the statement  without  qualifying  language as to  applicability of the lien
only to removable  personal  property,  located in an  identified  suite held by
Tenant.

     16.  INDEMNIFICATION.  Tenant hereby indemnifies and agrees to defend, save
and hold  Landlord  harmless  from and  against any and all Claims for injury or
death to persons or damage to property  occurring  within or about the Premises,
arising  directly or  indirectly  out of use or  occupancy  of the Premises or a
breach  or  default  by  Tenant  in the  performance  of any of its  obligations
hereunder, unless caused solely by the willful misconduct or gross negligence of
Landlord.  Landlord  shall not be liable to Tenant for,  and Tenant  assumes all
risk of damage to, personal property  (including,  without  limitation,  loss of
records kept within the Premises).  Tenant further waives any and all Claims for
injury to  Tenant's  business  or loss of income  relating to any such damage or
destruction of personal property  (including,  without  limitation,  any loss of
records).  Landlord  shall not be liable for any damages  arising  from any act,
omission or neglect of any tenant in the Project or of any other third party.

     17.   INSURANCE.   Landlord  shall  maintain  all  risk  property  and,  if
applicable, sprinkler damage insurance covering the full replacement cost of the
Project or such lesser  coverage  amount as  Landlord  may elect  provided  such
                                                                  --------
coverage  amount is not less than 90% of such full  replacement  cost.  Landlord
shall further procure and maintain commercial general liability insurance with a
single loss limit of not less than  $2,000,000  for bodily  injury and  property
damage with  respect to the Project.  Landlord  may,  but is not  obligated  to,
maintain such other insurance and additional coverages as it may deem necessary,
including, but not limited to, flood, environmental hazard and earthquake,  loss
or failure of building equipment,  errors and omissions,  rental loss during the
period of repair or  rebuilding,  workers'  compensation  insurance and fidelity
bonds  for  employees  employed  to  perform  services  and  insurance  for  any
improvements  installed  by  Tenant  or which are in  addition  to the  standard
improvements  customarily furnished by Landlord without regard to whether or not
such are made a part of the  Project.  All such  insurance  shall be included as
part of the Operating Expenses.  The Project may be included in a blanket policy
(in which  case the cost of such  insurance  allocable  to the  Project  will be
determined by Landlord based upon the insurer's cost calculations). Tenant shall
also reimburse Landlord for any increased premiums or additional insurance which
Landlord reasonably deems necessary as a result of Tenant's use of the Premises.

     Tenant,  at its sole cost and expense,  shall maintain during the Term: all
risk property  insurance with business  interruption and extra expense coverage,
covering the full replacement cost of all property and improvements installed or
placed in the  Premises by Tenant at  Tenant's  expense;  workers'  compensation
insurance  with no less than the  minimum  limits  required  by law;  employer's
liability  insurance  with such limits as required  by law;  commercial  general
liability  insurance,  with a  minimum  limit

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of not less than $2,000,000 per occurrence for bodily injury and property damage
with respect to the Premises and  pollution  legal  liability  insurance  with a
minimum limit of not less than $2,000,000 per occurrence. The commercial general
liability  insurance  policy  shall  name  Landlord,  its  officers,  directors,
employees,  managers, agents, invitees and contractors (collectively,  "LANDLORD
PARTIES"),   as  additional  insureds.  The  commercial  general  liability  and
pollution legal liability  insurance  policies shall insure on an occurrence and
not a claims-made  basis;  shall be issued by insurance  companies  which have a
rating of not less than policyholder  rating of A and financial  category rating
of at least Class X in "Best's  Insurance  Guide";  shall not be cancelable  for
nonpayment of premium  unless 10 days prior written notice shall have been given
to  Landlord  from  the  insurer;  contain  a  hostile  fire  endorsement  and a
contractual liability endorsement; and provide primary coverage to Landlord (any
policy  issued to Landlord  providing  duplicate  or similar  coverage  shall be
deemed excess over Tenant's policies).  Copies of such policies (if requested by
Landlord),  or certificates of insurance showing the limits of coverage required
hereunder and showing Landlord as an additional  insured,  along with reasonable
evidence  of the  payment  of  premiums  for the  applicable  period,  shall  be
delivered  to  Landlord by Tenant  upon  commencement  of the Term and upon each
renewal of said  insurance.  Tenant's  policy may be a "blanket  policy" with an
aggregate per location  endorsement which specifically  provides that the amount
of insurance  shall not be  prejudiced  by other  losses  covered by the policy.
Tenant shall, at least 5 days prior to the expiration of such policies,  furnish
Landlord with renewal certificates.

     In each  instance  where  insurance  is to name  Landlord as an  additional
insured,  Tenant  shall upon  written  request of Landlord  also  designate  and
furnish  certificates so evidencing  Landlord as additional  insured to: (i) any
lender of  Landlord  holding a security  interest  in the Project or any portion
thereof,  (ii) the landlord  under any lease  wherein  Landlord is tenant of the
real property on which the Project is located, if the interest of Landlord is or
shall  become that of a tenant under a ground or other  underlying  lease rather
than that of a fee  owner,  and/or  (iii) any  management  company  retained  by
Landlord to manage the Project.

     The property  insurance  obtained by Landlord  and Tenant  shall  include a
waiver of  subrogation  by the insurers and all rights based upon an  assignment
from its insured,  against Landlord or Tenant,  and their  respective  officers,
directors,  employees,  managers,  agents,  invitees and  contractors  ("RELATED
PARTIES"),  in  connection  with any loss or  damage  thereby  insured  against.
Neither party nor its  respective  Related  Parties shall be liable to the other
for loss or damage caused by any risk insured  against under property  insurance
required to be maintained  hereunder,  and each party waives any claims  against
the other party, and its respective  Related  Parties,  for such loss or damage.
The  failure  of a party to insure  its  property  shall  not void this  waiver.
Landlord and its respective  Related Parties shall not be liable for, and Tenant
hereby waives all claims  against such parties for,  business  interruption  and
losses  occasioned  thereby  sustained by Tenant or any person claiming  through
Tenant  resulting from any accident or occurrence in or upon the Premises or the
Project from any cause whatsoever. If the foregoing waivers shall contravene any
law with respect to exculpatory agreements,  the liability of Landlord or Tenant
shall be deemed not released but shall be secondary to the other's insurer.

     Landlord may require  insurance  policy limits to be raised to conform with
requirements of Landlord's lender and/or to bring coverage limits to levels then
being generally required of new tenants within the Project.

     18.  RESTORATION.  If, at any time  during  the Term,  the  Project  or the
Premises are damaged or destroyed by a fire or other insured casualty,  Landlord
shall  notify  Tenant  within 60 days after  discovery  of such damage as to the
amount of time Landlord reasonably estimates it will take to restore the Project
or the Premises,  as applicable (the "RESTORATION  PERIOD").  If the Restoration
Period is  estimated  to exceed 12 months (the  "MAXIMUM  RESTORATION  PERIOD"),
Landlord may, in such notice,  elect to terminate this Lease as of the date that
is 75 days after the date of  discovery  of such damage or  destruction.  Unless
Landlord so elects to terminate this Lease,  Landlord shall,  subject to receipt
of sufficient insurance proceeds (with any deductible to be treated as a current
Operating  Expense),  promptly restore the Premises  (excluding the improvements
installed  by Tenant or by  Landlord  and paid for by Tenant,  subject to delays
arising from the collection of insurance proceeds,  from Force Majeure events or
as needed to obtain any license,  clearance or other  authorization  of any kind
required  to enter

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into and  restore  the  Premises  issued by any  Governmental  Authority  having
jurisdiction over the use, storage, handling,  treatment,  generation,  release,
disposal,  removal or remediation of Hazardous  Materials (as defined in Section
                                                                         -------

30) in, on or about the Premises  (collectively referred to herein as "HAZARDOUS
--
MATERIALS CLEARANCES");  provided, however, that if repair or restoration of the
                         --------  -------
Premises is not substantially  complete as of the end of the Maximum Restoration
Period or, if longer,  the  Restoration  Period,  Landlord  may, in its sole and
absolute discretion,  elect not to proceed with such repair and restoration,  in
which event Landlord shall be relieved of its obligation to make such repairs or
restoration  and this Lease shall terminate as of the date that is 75 days after
the later of: (i) discovery of such damage or destruction,  or (ii) the date all
required Hazardous Materials Clearances are obtained,  but Landlord shall retain
any Rent paid and the right to any Rent payable by Tenant prior to such election
by Landlord or Tenant.

     Tenant, at its expense,  shall promptly perform,  subject to delays arising
from the  collection  of insurance  proceeds,  from Force Majeure (as defined in
Section 34) events or to obtain Hazardous  Material  Clearances,  all repairs or
----------
restoration  not  required  to  be  done  by  Landlord  and  shall  as  soon  as
commercially  reasonable  re-enter the Premises and commence  doing  business in
accordance  with  this  Lease.  Notwithstanding  the  foregoing,   Landlord  may
terminate  this Lease if the Premises are damaged  during the last 1 year of the
Term and Landlord  reasonably  estimates that it will take more than 3 months to
repair  such  damage,  or if  insurance  proceeds  are not  available  for  such
restoration.  Rent shall be abated from the date all required Hazardous Material
Clearances  are obtained  until the Premises are repaired and  restored,  in the
proportion which the area of the Premises, if any, which is not usable by Tenant
bears to the total area of the Premises,  unless  Landlord  provides Tenant with
other  space  during the period of repair  that is  suitable  for the  temporary
conduct of Tenant's business.  Tenant shall determine in its sole but reasonable
discretion if such space is suitable. Such abatement shall be the sole remedy of
Tenant,  and except as provided in this Section 18,  Tenant  waives any right to
                                        ----------
terminate the Lease by reason of damage or casualty loss.

     The  provisions  of this Lease,  including  this Section 18,  constitute an
                                                      ----------
express agreement between Landlord and Tenant with respect to any and all damage
to, or destruction of, all or any part of the Premises,  or any other portion of
the Project,  and any statute or regulation  which is now or may hereafter be in
effect shall have no  application  to this Lease or any damage or destruction to
all or any part of the Premises or any other portion of the Project, the parties
hereto  expressly  agreeing  that  this  Section  18  sets  forth  their  entire
understanding and agreement with respect to such matters.

     19. CONDEMNATION.  If the whole or any material part of the Premises or the
Project  is taken for any public or  quasi-public  use under  governmental  law,
ordinance, or regulation,  or by right of eminent domain, or by private purchase
in lieu  thereof (a "TAKING" or  "TAKEN"),  and the Taking  would in  Landlord's
reasonable judgment either prevent or materially  interfere with Tenant's use of
the Premises or  materially  interfere  with or impair  Landlord's  ownership or
operation of the Project,  then upon written notice by Landlord this Lease shall
terminate and Rent shall be apportioned as of said date. If part of the Premises
shall be Taken,  and this Lease is not  terminated as provided  above,  Landlord
shall promptly restore the Premises and the Project as nearly as is commercially
reasonable  under the  circumstances  to their  condition  prior to such partial
Taking and the rentable  square  footage of the  Building,  the rentable  square
footage of the  Premises,  Tenant's  Share of  Operating  Expenses  and the Rent
payable  hereunder  during the unexpired Term shall be reduced to such extent as
may be fair and  reasonable  under  the  circumstances.  Upon  any such  Taking,
Landlord  shall be entitled  to receive the entire  price or award from any such
Taking  without any  payment to Tenant,  and Tenant  hereby  assigns to Landlord
Tenant's  interest,  if any, in such award.  Tenant shall have the right, to the
extent that same shall not diminish  Landlord's  award, to make a separate claim
against the condemning authority (but not Landlord) for such compensation as may
be separately awarded or recoverable by Tenant for moving expenses and damage to
Tenant's trade  fixtures,  if a separate award for such items is made to Tenant.
Tenant hereby waives any and all rights it might  otherwise have pursuant to any
provision  of state law to  terminate  this Lease  upon a partial  Taking of the
Premises or the Project.

     20.  EVENTS OF DEFAULT.  Each of the  following  events  shall be a default
("DEFAULT") by Tenant under this Lease:

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     (a) PAYMENT  DEFAULTS.  Tenant shall fail to pay any installment of Rent or
any other payment hereunder when due.

     (b) INSURANCE.  Any insurance  required to be maintained by Tenant pursuant
to this  Lease  shall be  canceled  or  terminated  or shall  expire or shall be
reduced or materially  changed, or Landlord shall receive a notice of nonrenewal
of any such insurance and Tenant shall fail to obtain  replacement  insurance at
least 20 days before the expiration of the current coverage.

     (c) ABANDONMENT. Tenant shall abandon the Premises.

     (d) IMPROPER TRANSFER.  Tenant shall assign, sublease or otherwise transfer
or attempt to transfer all or any portion of Tenant's  interest in this Lease or
the Premises except as expressly  permitted herein, or Tenant's interest in this
Lease shall be attached,  executed upon, or otherwise judicially seized and such
action is not released within 90 days of the action.

     (e) LIENS.  Tenant shall fail to discharge or otherwise  obtain the release
of any lien placed upon the  Premises in  violation of this Lease within 15 days
after any such lien is filed against the Premises.

     (f)  INSOLVENCY  EVENTS.  Tenant or any  guarantor  or  surety of  Tenant's
obligations  hereunder shall:  (A) make a general  assignment for the benefit of
creditors;  (B) commence any case, proceeding or other action seeking to have an
order  for  relief  entered  on its  behalf as a debtor  or to  adjudicate  it a
bankrupt  or  insolvent,  or seeking  reorganization,  arrangement,  adjustment,
liquidation,   dissolution  or  composition  of  it  or  its  debts  or  seeking
appointment of a receiver,  trustee,  custodian or other similar official for it
or  for  all  or of  any  substantial  part  of  its  property  (collectively  a
"PROCEEDING  FOR RELIEF");  (C) become the subject of any  Proceeding for Relief
which is not  dismissed  within 90 days of its  filing  or entry;  or (D) die or
suffer a legal disability (if Tenant,  guarantor, or surety is an individual) or
be  dissolved  or otherwise  fail to maintain  its legal  existence  (if Tenant,
guarantor or surety is a corporation, partnership or other entity).

     (g)  ESTOPPEL  CERTIFICATE  OR  SUBORDINATION  AGREEMENT.  Tenant  fails to
execute any document  required from Tenant under Sections 23 or 27 within 5 days
                                                 -----------    --
after a second notice requesting such document.

     (h) OTHER DEFAULTS.  Tenant shall fail to comply with any provision of this
Lease other than those specifically  referred to in this Section 20, and, except
                                                         ----------
as otherwise expressly provided herein, such failure shall continue for a period
of 15 days after written notice thereof from Landlord to Tenant.

Any notice  given under  Section  20(h)  hereof  shall:  (i) specify the alleged
                         -------------
default, (ii) demand that Tenant cure such default, (iii) be in lieu of, and not
in  addition  to,  or shall be  deemed  to be,  any  notice  required  under any
provision  of  applicable  law,  and  (iv)  not  be  deemed  a  forfeiture  or a
termination  of this Lease  unless  Landlord  elects  otherwise  in such notice;
provided  that if the nature of Tenant's  default  pursuant to Section  20(h) is
--------                                                       -------------
such that it cannot be cured by the  payment  of money and  reasonably  requires
more than 15 days to cure,  then Tenant  shall not be deemed to be in default if
Tenant  commences such cure within said 15 day period and thereafter  diligently
prosecutes the same to completion;  provided,  however,  that such cure shall be
completed no later than 45 days from the date of Landlord's notice.

     21. LANDLORD'S REMEDIES.

     (a) Upon a Default by Tenant  hereunder,  Landlord may,  without waiving or
releasing any obligation of Tenant hereunder,  make such payment or perform such
act. All sums so paid or incurred by Landlord,  together with interest  thereon,
from the date such sums were paid or  incurred,  at the annual rate equal to 10%
per annum  (the  "DEFAULT  RATE"),  shall be payable  to  Landlord  on demand as
additional Rent. Nothing herein shall be construed to create or impose a duty on
Landlord to mitigate any damages resulting from Tenant's Default hereunder.

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     (b) LATE PAYMENT RENT. Late payment by Tenant to Landlord of Rent and other
sums due will cause Landlord to incur costs not  contemplated by this Lease, the
exact  amount  of  which  will  be  extremely  difficult  and  impracticable  to
ascertain. Such costs include, but are not limited to, processing and accounting
charges and late  charges  which may be imposed on Landlord  under any  Mortgage
covering the Premises.  Therefore, if any installment of Rent due from Tenant is
not  received  by  Landlord  within 5 days  after the date such  payment is due,
Tenant  shall pay to Landlord an  additional  sum of 6% of the overdue Rent as a
late  charge.  The  parties  agree that this late charge  represents  a fair and
reasonable  estimate of the costs  Landlord will incur by reason of late payment
by Tenant.  In  addition to the late  charge,  Rent not paid when due shall bear
interest at the Default Rate from the 5th day after the date due until paid.

     (c) RE-ENTRY.  Landlord  shall have the right,  immediately  or at any time
thereafter, without further notice to Tenant (unless otherwise provided herein),
to enter  the  Premises,  without  terminating  this  Lease or being  guilty  of
trespass,  and do any and all acts as  Landlord  may deem  necessary,  proper or
convenient to cure such  default,  for the account and at the expense of Tenant,
any notice to quit or notice of  Landlord's  intention to re-enter  being hereby
expressly  waived,  and Tenant agrees to pay to Landlord as Additional  Rent all
damage and/or expense  incurred by Landlord in so doing,  including  interest at
the  Default  Rate,  from the due date  until the date  payment is  received  by
Landlord.

     (d) TERMINATION.  Landlord shall have the right to terminate this Lease and
Tenant's right to possession of the Premises and, with or without legal process,
take possession of the Premises and remove Tenant, any occupant and any property
therefrom,  using  such  force as may be  necessary,  without  being  guilty  of
trespass and without  relinquishing  any rights of Landlord against Tenant,  any
notice to quit,  or notice of  Landlord's  intention  to re-enter  being  hereby
expressly waived.  Landlord shall be entitled to recover damages from Tenant for
all amounts  covenanted  to be paid during the remainder of the Term (except for
the period of any holdover by Tenant, in which case the Rent stated at Section 7
herein  shall  apply),  which may be  accelerated  by  Landlord  at its  option,
together with (i) all expenses of any  proceedings  (including,  but not limited
to,  legal  expenses  and  attorney's  fees) which may be necessary in order for
Landlord  to  recover  possession  of the  Premises,  (ii) the  expenses  of the
re-renting of the Premises (including,  but not limited to, any commissions paid
to any real estate agent, advertising expense and the costs of such alterations,
repairs,  replacements  or  modifications  that Landlord,  in its sole judgment,
considers  advisable  and necessary  for the purpose of  re-renting),  and (iii)
interest  computed at the Default  Rate from the due date until paid;  provided,
however,  that there  shall be credited  against the amount of such  damages all
amounts  received by Landlord from such  re-renting  of the  Premises,  with any
overage being refunded to Tenant.  Landlord and Tenant expressly agree, however,
that there shall be no credit against the amount of such damages relating to the
payment  of  Additional  Rent due in  accordance  with the  terms of  subsection
                                                                      ----------
2(b)(x)  of  this  Lease.  Landlord  shall  in no  event  be  liable  in any way
-------
whatsoever  for  failure  to  re-rent  the  Premises  or, in the event  that the
Premises  are  re-rented,  for  failure to collect the rent  thereof  under such
re-renting  and Tenant  expressly  waives any duty of the  Landlord  to mitigate
damages. No act or thing done by Landlord shall be deemed to be an acceptance of
a surrender of the Premises,  unless Landlord shall execute a written  agreement
of surrender with Tenant.  Tenant's liability  hereunder shall not be terminated
by the  execution of a new lease of the  Premises by  Landlord,  unless that new
lease expressly so states. In the event Landlord does not exercise its option to
accelerate  the  payment of amounts  owed as provided  hereinabove,  then Tenant
agrees to pay to Landlord,  upon demand,  the amount of damages herein  provided
after the amount of such  damages  for any month  shall  have been  ascertained;
provided,  however, that any expenses incurred by Landlord shall be deemed to be
a part of the  damages  for the  month in which  they  were  incurred.  Separate
actions  may be  maintained  each month or at other  times by  Landlord  against
Tenant to recover the damages  then due,  without  waiting  until the end of the
term of this Lease to determine  the aggregate  amount of such  damages.  Tenant
hereby expressly waives any and all rights of redemption granted by or under any
present  or  future  laws  in  the  event  of  Tenant  being  evicted  or  being
dispossessed for any cause, or in the event of Landlord obtaining  possession of
the Premises by reason of the  violation by Tenant of any of the  covenants  and
conditions of this Lease.

     (e) LIEN FOR RENT.  Upon any  default  by Tenant in the  payment of Rent or
other amounts owed  hereunder,  Landlord  shall have a lien upon the property of
Tenant in the Premises for the amount of

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such  unpaid  amounts,  and  Tenant  hereby  specifically  waives  any  and  all
exemptions  allowed  by law.  In such  event,  Tenant  shall not  remove  any of
Tenant's  property from the Premises  except with the prior  written  consent of
Landlord,  and Landlord  shall have the right and privilege,  at its option,  to
take possession of all Tenant's  property in the Premises,  to store the same on
the  Premises,  or to remove it and store it in such place as may be selected by
Landlord,  at Tenant's risk and expense.  If Tenant fails to redeem the personal
property so seized,  by payment of whatever  sum may be due  Landlord  hereunder
(including all storage costs),  Landlord shall have the right, after twenty (20)
days written  notice to Tenant of its  intention to do so, to sell such personal
property so seized at public or private sale and upon such terms and  conditions
as may appear  advantageous  to  Landlord,  and after the  payment of all proper
charges  incident to such sale, apply the proceeds thereof to the payment of any
balance  due to  Landlord  on  account  of rent or other  obligations  of Tenant
pursuant  to this  Lease.  In the event  there shall then remain in the hands of
Landlord any balance realized from the sale of said personal property,  the same
shall be paid over to Tenant.  The exercise of the foregoing  remedy by Landlord
shall not relieve or discharge Tenant from any deficiency owed to Landlord which
Landlord  has the right to enforce  pursuant  to any of the  provisions  of this
Lease.  Tenant shall also be liable for all expenses  incident to the  foregoing
process, including any auctioneer or attorney's fees or commissions.

     (f) OTHER REMEDIES. In addition to the foregoing,  Landlord, at its option,
without  further  notice or demand to Tenant,  shall  have all other  rights and
remedies provided at law or in equity.

     21. ASSIGNMENT AND SUBLETTING.

     (a) GENERAL  PROHIBITION.  Without Landlord's prior written consent subject
to and on the  conditions  described  in this  Section  22,  Tenant  shall  not,
                                               -----------
directly or indirectly, voluntarily or by operation of law, assign this Lease or
sublease the Premises or any part thereof or mortgage,  pledge,  or  hypothecate
its leasehold  interest or grant any  concession or license within the Premises,
and any attempt to do any of the  foregoing  shall be void and of no effect.  If
Tenant is a corporation, partnership or limited liability company, the shares or
other  ownership  interests  thereof which are not actively  traded upon a stock
exchange or in the  over-the-counter  market,  a transfer or series of transfers
whereby  50% or more of the issued  and  outstanding  shares or other  ownership
interests  of such  corporation  are,  or voting  control is,  transferred  (but
excepting  transfers upon deaths of individual  owners) from a person or persons
or entity or entities  which were owners  thereof at time of  execution  of this
Lease to persons or  entities  who were not owners of shares or other  ownership
interests of the corporation,  partnership or limited  liability company at time
of  execution  of this  Lease,  shall be  deemed  an  assignment  of this  Lease
requiring the consent of Landlord as provided in this Section 22.
                                                      ----------

     (b) PERMITTED TRANSFERS. If Tenant desires to assign, sublease, hypothecate
or  otherwise  transfer  this  Lease or sublet  the  Premises,  then at least 15
business  days,  before the date Tenant desires the assignment or sublease to be
effective  (the  "ASSIGNMENT  DATE"),  Tenant shall give  Landlord a notice (the
"ASSIGNMENT  NOTICE") containing such information about the proposed assignee or
sublessee,  including  the  proposed  use  of the  Premises  and  any  Hazardous
Materials proposed to be used, stored handled, treated, generated in or released
or disposed of from the Premises,  the Assignment Date, any relationship between
Tenant and the  proposed  assignee  or  sublessee,  and all  material  terms and
conditions  of the  proposed  assignment  or  sublease,  including a copy of any
proposed assignment or sublease in its final form, and such other information as
Landlord may deem  reasonably  necessary  or  appropriate  to its  consideration
whether to grant its consent.  Landlord may, by giving  written notice to Tenant
within 15 business days after receipt of the Assignment  Notice:  (i) grant such
consent,  (ii) refuse such consent, in its sole and absolute discretion,  if the
proposed assignment, hypothecation or other transfer or subletting concerns more
than  (together  with all other then  effective  subleases) 50% of the Premises,
(iii)  refuse  such  consent,  in its  reasonable  discretion,  if the  proposed
subletting  concerns  (together with all other then effective  subleases) 50% or
less of the Premises  (provided  that  Landlord  shall further have the right to
review and approve or  disapprove  the  proposed  form of sublease  prior to the
effective  date of any such  subletting),  or (iv)  terminate  this  Lease  with
respect to the space  described in the  Assignment  Notice as of the  Assignment
Date (an "ASSIGNMENT TERMINATION").  If Landlord delivers notice of its election
to exercise an Assignment  Termination,  Tenant shall have the right to withdraw
such  Assignment  Notice by written notice to Landlord of such election within 5
business  days

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after  Landlord's  notice  electing to exercise the Assignment  Termination.  If
Tenant withdraws such Assignment Notice, this Lease shall continue in full force
and effect. If Tenant does not withdraw such Assignment Notice,  this Lease, and
the term and estate herein  granted,  shall  terminate as of the Assignment Date
with respect to the space  described in such  Assignment  Notice.  No failure of
Landlord to exercise  any such option to terminate  this Lease,  or to deliver a
timely  notice  in  response  to the  Assignment  Notice,  shall be deemed to be
Landlord's  consent to the  proposed  assignment,  sublease  or other  transfer.
Tenant shall reimburse Landlord for all of Landlord's  reasonable  out-of-pocket
expenses in connection with its consideration of any Assignment Notice.

     (c)  ADDITIONAL  CONDITIONS.  As a  condition  to any  such  assignment  or
subletting, whether or not Landlord's consent is required, Landlord may require:

          (i) that any  assignee or subtenant  agree,  in writing at the time of
     such  assignment or  subletting,  that if Landlord  gives such party notice
     that  Tenant is in default  under this Lease,  such party shall  thereafter
     make all payments otherwise due Tenant directly to Landlord, which payments
     will be received by Landlord  without any  liability  except to credit such
     payment  against those due under the Lease,  and any such third party shall
     agree to attorn to Landlord or its successors and assigns should this Lease
     be terminated for any reason; provided, however, in no event shall Landlord
                                   --------  -------
     or its successors or assigns be obligated to accept such attornment; and

          (ii) A list of Hazardous Materials, certified by the proposed assignee
     or  sublessee  to be true and  correct,  which  the  proposed  assignee  or
     sublessee intends to use, store, handle,  treat,  generate in or release or
     dispose  of from  the  Premises,  together  with  copies  of all  documents
     relating to such use, storage, handling, treatment,  generation, release or
     disposal of Hazardous  Materials  by the proposed  assignee or subtenant in
     the  Premises  or on the  Project,  prior  to the  proposed  assignment  or
     subletting,  including, without limitation: permits; approvals; reports and
     correspondence;  storage  and  management  plans;  plans  relating  to  the
     installation  of any storage  tanks to be installed in or under the Project
     (provided,  said  installation  of  tanks  shall  only be  permitted  after
     Landlord  has given its  written  consent to do so,  which  consent  may be
     withheld in Landlord's sole and absolute discretion); and all closure plans
     or any other  documents  required by any and all  federal,  state and local
     Governmental  Authorities  for any storage tanks  installed in, on or under
     the Project for the closure of any such tanks.  Neither Tenant nor any such
     proposed  assignee or subtenant is required,  however,  to provide Landlord
     with any  portion(s)  of the such  documents  containing  information  of a
     proprietary nature which, in and of themselves,  do not contain a reference
     to any Hazardous Materials or hazardous activities.

     (d) NO RELEASE OF TENANT,  SHARING  OF EXCESS  RENTS.  Notwithstanding  any
assignment  or  subletting,  Tenant  and any  guarantor  or surety  of  Tenant's
obligations  under  this Lease  shall at all times  remain  fully and  primarily
responsible  and liable for the payment of Rent and for  compliance  with all of
Tenant's other  obligations  under this Lease.  If the Rent due and payable by a
sublessee  or  assignee  (or a  combination  of the  rental  payable  under such
sublease  or  assignment  plus  any  bonus or other  consideration  therefor  or
incident  thereto in any form)  exceeds  the rental  payable  under this  Lease,
(excluding  however,  any Rent payable under this Section) ("EXCESS RENT"), then
Tenant shall be bound and obligated to pay Landlord as Additional Rent hereunder
50% of such Excess Rent within 10 days following  receipt thereof by Tenant.  If
Tenant shall sublet the Premises or any part thereof,  Tenant hereby immediately
and irrevocably assigns to Landlord,  as security for Tenant's obligations under
this Lease, all rent from any such  subletting,  and Landlord as assignee and as
attorney-in-fact  for Tenant,  or a receiver for Tenant  appointed on Landlord's
application,  may  collect  such rent and apply it toward  Tenant's  obligations
under this Lease;  except that, until the occurrence of a Default,  Tenant shall
have the right to collect such rent.

     (e) NO WAIVER. The consent by Landlord to an assignment or subletting shall
not  relieve  Tenant or any  assignees  of this Lease or any  sublessees  of the
Premises  from  obtaining  the consent of Landlord to any further  assignment or
subletting  nor shall it release  Tenant or any  assignee or sublessee of Tenant
from  full and  primary  liability  under  the  Lease.  The  acceptance  of Rent
hereunder,  or the  acceptance of performance  of any other term,  covenant,  or
condition  thereof,  from any other person or

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entity shall not be deemed to be a waiver of any of the provisions of this Lease
or a consent to any subletting, assignment or other transfer of the Premises.

     (f)  PRIOR  CONDUCT  OF  PROPOSED  TRANSFEREE.  Notwithstanding  any  other
provision  of this  Section 22, if (i) the  proposed  assignee or  sublessee  of
                    ----------
Tenant has been required by any prior landlord, lender or Governmental Authority
to take remedial action in connection with Hazardous  Materials  contaminating a
property,  where the  contamination  resulted from such party's action or use of
the property in question,  (ii) the proposed assignee or sublessee is subject to
an enforcement order issued by any Governmental Authority in connection with the
use, storage, handling, treatment,  generation, release or disposal of Hazardous
Materials  (including,  without limitation,  any order related to the failure to
make a required  reporting to any Governmental  Authority),  or (iii) because of
the existence of a  pre-existing  environmental  condition in the vicinity of or
underlying  the  Project,  the  risk  that  Landlord  would  be  targeted  as  a
responsible  party in  connection  with  the  remediation  of such  pre-existing
environmental  condition  would be materially  increased or  exacerbated  by the
proposed use of  Hazardous  Materials by such  proposed  assignee or  sublessee,
Landlord shall have the absolute right to refuse to consent to any assignment or
subletting to any such party.

     22. ESTOPPEL CERTIFICATE.  Tenant shall, within 10 business days of written
notice from Landlord, execute, acknowledge and deliver a statement in writing in
any form reasonably requested by a proposed lender or purchaser,  (i) certifying
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)  and the dates to which the  rental and
other charges are paid in advance, if any, (ii) acknowledging that there are not
any uncured  defaults  on the part of Landlord  hereunder,  or  specifying  such
defaults if any are claimed,  and (iii) setting  forth such further  information
with  respect to the status of this Lease or the  Premises  as may be  requested
thereon.  Any such statement may be relied upon by any prospective  purchaser or
encumbrancer  of all or any portion of the real  property of which the  Premises
are a part.  Tenant's  failure to deliver such statement within such time shall,
at the option of Landlord,  constitute a Default  under this Lease,  and, in any
event,  shall be  conclusive  upon  Tenant  that the Lease is in full  force and
effect and without  modification except as may be represented by Landlord in any
certificate prepared by Landlord and delivered to Tenant for execution.

     23. QUIET  ENJOYMENT.  So long as Tenant shall perform all of the covenants
and agreements herein required to be performed by Tenant,  Tenant shall, subject
to the terms of this Lease,  at all times  during the Term,  have  peaceful  and
quiet enjoyment of the Premises against any person claiming by, through or under
Landlord.

     24. PRORATIONS.  All prorations  required or permitted to be made hereunder
shall be made on the basis of a 360 day year and 30 day months.

     25. RULES AND  REGULATIONS.  Tenant shall, at all times during the Term and
any extension  thereof,  comply with all reasonable rules and regulations at any
time or from time to time  established by Landlord  covering use of the Premises
and the  Project.  The current  rules and  regulations  are  attached  hereto as
EXHIBIT E. If there is any conflict between said rules and regulations and other
provisions of this Lease,  the terms and provisions of this Lease shall control.
Landlord  shall not have any liability or obligation for the breach of any rules
or  regulations by other tenants in the Project and shall not enforce such rules
and regulations in a discriminatory manner.

     26.  SUBORDINATION.  This Lease and Tenant's  interest and rights hereunder
are hereby made and shall be subject and subordinate at all times to the lien of
any Mortgage now existing or hereafter  created on or against the Project or the
Premises,   and   all   amendments,   restatements,   renewals,   modifications,
consolidations,  refinancing,  assignments and extensions  thereof,  without the
necessity  of any  further  instrument  or act on the part of Tenant;  provided,
                                                                       --------

however  that so long as  there  is no  Default  hereunder,  Tenant's  right  to
-------
possession  of the  Premises  shall not be  disturbed  by the Holder of any such
Mortgage.  Tenant agrees, at the election of the Holder of any such Mortgage, to
attorn to any such Holder. Tenant agrees upon demand to execute, acknowledge and
deliver such instruments, confirming such subordination, and such instruments of
attornment  as  shall  be  requested  by any  such  Holder,

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provided any such instruments  contain  appropriate  non-disturbance  provisions
assuring  Tenant's  quiet  enjoyment  of the Premises as set forth in Section 24
hereof. Tenant hereby appoints Landlord  attorney-in-fact for Tenant irrevocably
(such power of attorney being coupled with an interest) to execute,  acknowledge
and deliver any such  instrument and  instruments  for and in the name of Tenant
and to cause any such instrument to be recorded.  Notwithstanding the foregoing,
any such Holder may at any time subordinate its Mortgage to this Lease,  without
Tenant's consent, by notice in writing to Tenant, and thereupon this Lease shall
be deemed prior to such Mortgage  without  regard to their  respective  dates of
execution,  delivery or  recording  and in that event such Holder shall have the
same  rights with  respect to this Lease as though this Lease had been  executed
prior to the  execution,  delivery and  recording of such  Mortgage and had been
assigned to such Holder.  The term "MORTGAGE"  whenever used in this Lease shall
be  deemed  to  include  deeds of  trust,  security  assignments  and any  other
encumbrances, and any reference to the "HOLDER" of a Mortgage shall be deemed to
include the beneficiary under a deed of trust.

     27.  SURRENDER.  Upon the expiration of the Term or earlier  termination of
Tenant's right of possession, Tenant shall surrender the Premises to Landlord in
the same condition as received,  subject to any Alterations,  Installations  and
Tenant Improvements made pursuant to the terms of this Lease or the Work Letter,
free of Hazardous Materials brought upon, kept, used, stored, handled,  treated,
generated in, or released or disposed of from,  the Premises by any person other
than a Landlord Party (collectively, "TENANT HAZMAT OPERATIONS") and released of
all  Hazardous  Materials  Clearances,  broom clean,  ordinary wear and tear and
casualty loss and condemnation covered by Sections 18 and 19 excepted.  At least
3 months  prior to the  surrender  of the  Premises,  Tenant  shall  deliver  to
Landlord a narrative  description  of the actions  proposed  (or required by any
Governmental Authority) to be taken by Tenant in order to surrender the Premises
(including any Installations permitted by Landlord to remain in the Premises) at
the expiration or earlier termination of the Term, free from any residual impact
from the Tenant HazMat  Operations and otherwise  released for  unrestricted use
and occupancy (the "SURRENDER  PLAN").  Such Surrender Plan shall be accompanied
by a current listing of (i) all Hazardous Materials licenses and permits held by
or on behalf of any Tenant  Party with  respect  to the  Premises,  and (ii) all
Hazardous  Materials used,  stored,  handled,  treated,  generated,  released or
disposed of from the  Premises,  and shall be subject to the review and approval
of  Landlord's  environmental  consultant.  In  connection  with the  review and
approval of the  Surrender  Plan,  upon the request of  Landlord,  Tenant  shall
deliver  to  Landlord  or  its  consultant   such   additional   non-proprietary
information concerning Tenant HazMat Operations as Landlord shall request. On or
before  such  surrender,  Tenant  shall  deliver to Landlord  evidence  that the
approved  Surrender Plan shall have been  satisfactorily  completed and Landlord
shall have the right,  subject to reimbursement at Tenant's expense as set forth
below, to cause Landlord's  environmental consultant to inspect the Premises and
perform such  additional  procedures  as may be deemed  reasonably  necessary to
confirm that the Premises  are, as of the  effective  date of such  surrender or
early termination of the Lease, free from any residual impact from Tenant HazMat
Operations.  Tenant shall reimburse Landlord, as Additional Rent, for the actual
out-of  pocket  expense  incurred  by  Landlord  for  Landlord's   environmental
consultant  to review and approve the  Surrender  Plan and to visit the Premises
and  verify  satisfactory  completion  of the same,  which cost shall not exceed
$4,000.  Landlord  shall have the  unrestricted  right to deliver such Surrender
Plan and any report by Landlord's  environmental  consultant with respect to the
surrender of the Premises to third parties.

     If Tenant  shall fail to prepare or submit a  Surrender  Plan  approved  by
Landlord, or if Tenant shall fail to complete the approved Surrender Plan, or if
such  Surrender  Plan,  whether  or not  approved  by  Landlord,  shall  fail to
adequately  address any residual  effect of Tenant HazMat  Operations  in, on or
about the  Premises,  Landlord  shall  have the right to take  such  actions  as
Landlord  may  reasonably  deem  necessary  to assure that the  Premises and the
Project  are  surrendered  free from any  residual  impact  from  Tenant  HazMat
Operations,  the reasonable  cost of which actions shall be reimbursed by Tenant
as Additional Rent.

     Tenant shall immediately return to Landlord all keys and/or access cards to
parking, the Project,  restrooms or all or any portion of the Premises furnished
to or  otherwise  procured  by Tenant.  If any such  access card or key is lost,
Tenant shall pay to Landlord, at Landlord's election, either the reasonable cost
of  replacing  such  lost  access  card  or  key  or  the  reasonable   cost  of
reprogramming  the access  security system in which such access card was used or
changing  the lock or locks  opened  by such lost key.  Any

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Tenant's  Property,  Alterations  and  property  not so  removed  by  Tenant  as
permitted  or  required  herein  shall be deemed  abandoned  and may be  stored,
removed,  and disposed of by Landlord at Tenant's expense, and Tenant waives all
claims  against  Landlord for any damages  resulting from  Landlord's  retention
and/or  disposition of such property.  All  obligations of Tenant  hereunder not
fully performed as of the termination of the Term,  including the obligations of
Tenant  under  Section  30  hereof,  shall  survive  the  expiration  or earlier
               -----------
termination of the Term, including,  without limitation,  indemnity obligations,
payment  obligations  with  respect  to  Rent  and  obligations  concerning  the
condition and repair of the Premises.

     28. WAIVER OF JURY TRIAL.  TENANT AND LANDLORD  WAIVE ANY RIGHT TO TRIAL BY
JURY OR TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN
CONTRACT,  TORT, OR OTHERWISE,  BETWEEN  LANDLORD AND TENANT ARISING OUT OF THIS
LEASE OR ANY OTHER INSTRUMENT,  DOCUMENT,  OR AGREEMENT EXECUTED OR DELIVERED IN
CONNECTION HEREWITH OR THE TRANSACTIONS RELATED HERETO.

     29. ENVIRONMENTAL REQUIREMENTS.

     (a) PROHIBITION/COMPLIANCE/INDEMNITY.  Tenant shall not cause or permit any
Hazardous  Materials (as hereinafter  defined) to be brought upon,  kept,  used,
stored,  handled,  treated,  generated  in or about,  or released or disposed of
from,  the  Premises or the Project in  violation  of  applicable  Environmental
Requirements  (as hereinafter  defined) by Tenant or any Tenant Party. If Tenant
breaches the obligation stated in the preceding sentence,  or if the presence of
Hazardous  Materials in the Premises during the Term or any holding over results
in  contamination  of the Premises,  the Project or any adjacent  property or if
contamination of the Premises, the Project or any adjacent property by Hazardous
Materials brought into, kept, used, stored,  handled,  treated,  generated in or
about,  or  released  or disposed  of from,  the  Premises by anyone  other than
Landlord and  Landlord's  employees,  agents and  contractors  otherwise  occurs
during the Term or any holding over, Tenant hereby  indemnifies and shall defend
and hold Landlord, its officers,  directors,  employees,  agents and contractors
harmless from any and all actions (including,  without  limitation,  remedial or
enforcement  actions of any kind,  administrative or judicial  proceedings,  and
orders or  judgments  arising out of or  resulting  therefrom),  costs,  claims,
damages (including, without limitation,  punitive damages and damages based upon
diminution  in  value  of the  Premises  or the  Project,  or the  loss  of,  or
restriction  on, use of the  Premises or any portion of the  Project),  expenses
(including, without limitation, reasonable attorneys', consultants' and experts'
fees,  court costs and amounts  paid in  settlement  of any claims or  actions),
fines,  forfeitures  or  other  civil,  administrative  or  criminal  penalties,
injunctive or other relief (whether or not based upon personal injury,  property
damage,  or contamination  of, or adverse effects upon, the  environment,  water
tables   or   natural   resources),   liabilities   or   losses   (collectively,
"ENVIRONMENTAL CLAIMS") which arise during or after the Term as a result of such
contamination.  This  indemnification  of Landlord by Tenant  includes,  without
limitation,  reasonable  costs incurred in connection with any  investigation of
site conditions or any cleanup,  treatment,  remedial,  removal,  or restoration
work required by any federal,  state or local Governmental  Authority because of
Hazardous Materials present in the air, soil or ground water above, on, or under
the Premises.  Without limiting the foregoing,  if the presence of any Hazardous
Materials on the Premises,  the Building,  the Project or any adjacent  property
caused or permitted by Tenant or any Tenant Party  results in any  contamination
of the Premises,  the Project or any adjacent  property,  Tenant shall  promptly
take  all  actions  at its  sole  expense  and  in  accordance  with  applicable
Environmental  Requirements as are necessary to return the Premises, the Project
or any adjacent  property to the  condition  existing  prior to the time of such
contamination,  provided that Landlord's  approval of such action shall first be
obtained,  which  approval  shall not  unreasonably  be withheld so long as such
actions would not potentially have any material adverse  long-term or short-term
effect on the Premises or the Project.

     (b)  BUSINESS.  Landlord  acknowledges  that it is not the  intent  of this
Section 30 to prohibit  Tenant from using the  Premises for the  Permitted  Use.
Tenant may operate its business  according to prudent industry practices so long
as the use or presence of Hazardous Materials is strictly and properly monitored
according  to all then  applicable  Environmental  Requirements.  As a  material
inducement to Landlord to allow Tenant to use Hazardous  Materials in connection
with  its  business,   Tenant  agrees  to  deliver  to  Landlord  prior  to  the
Commencement  Date a list  identifying  each type of  Hazardous  Materials to

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be brought upon, kept, used, stored, handled, treated, generated on, or released
or disposed of from,  the  Premises and setting  forth any and all  governmental
approvals or permits  required in connection  with the presence,  use,  storage,
handling, treatment, generation, release or disposal of such Hazardous Materials
on or from the Premises  ("HAZARDOUS  MATERIALS List").  Tenant shall deliver to
Landlord an updated Hazardous Materials List at least once a year and shall also
deliver an updated list before any new Hazardous Material is brought onto, kept,
used, stored, handled,  treated,  generated on, or released or disposed of from,
the Premises.  Tenant shall  deliver to Landlord true and correct  copies of the
following  documents  (the "HAZ MAT  DOCUMENTS")  relating to the use,  storage,
handling,  treatment,  generation,  release or disposal of  Hazardous  Materials
prior to the Commencement Date, or if unavailable at that time,  concurrent with
the receipt from or submission to a Governmental Authority:  permits; approvals;
reports and  correspondence;  storage and management plans, notice of violations
of any Legal  Requirements;  plans relating to the  installation  of any storage
tanks to be installed in or under the Project  (provided,  said  installation of
tanks  shall only be  permitted  after  Landlord  has given  Tenant its  written
consent to do so, which consent may be withheld in Landlord's  sole and absolute
discretion);  all closure plans or any other  documents  required by any and all
federal,  state  and  local  Governmental  Authorities  for  any  storage  tanks
installed  in, on or under the Project for the closure of any such tanks;  and a
Surrender Plan (to the extent  surrender in accordance with Section 28 cannot be
                                                            ----------
accomplished in 3 months). Tenant is not required,  however, to provide Landlord
with  any  portion(s)  of the  Haz Mat  Documents  containing  information  of a
proprietary  nature which,  in and of themselves,  do not contain a reference to
any Hazardous  Materials or hazardous  activities.  It is not the intent of this
Section to provide  Landlord  with  information  which could be  detrimental  to
Tenant's   business  should  such  information   become  possessed  by  Tenant's
competitors.

     (c) TENANT  REPRESENTATION  AND  WARRANTY.  Tenant  hereby  represents  and
warrants to Landlord that (i) neither  Tenant nor any of its legal  predecessors
has been required by any prior landlord, lender or Governmental Authority at any
time  to  take  remedial   action  in  connection   with   Hazardous   Materials
contaminating  a property  which  contamination  was permitted by Tenant of such
predecessor or resulted from Tenant's or such predecessor's action or use of the
property in question,  and (ii) Tenant is not subject to any  enforcement  order
issued  by any  Governmental  Authority  in  connection  with the use,  storage,
handling,  treatment,  generation,  release or disposal of  Hazardous  Materials
(including,  without  limitation,  any order  related  to the  failure to make a
required reporting to any Governmental  Authority).  If Landlord determines that
this  representation  and  warranty  was not true as of the date of this  lease,
Landlord  shall have the right to terminate  this Lease in  Landlord's  sole and
absolute discretion.

     (d) Landlord  shall have the right to conduct  annual tests of the Premises
to  determine  whether  any  contamination  of the  Premises  or the Project has
occurred as a result of Tenant's  use.  Tenant shall be required to pay the cost
of such annual test of the Premises;  provided, however, that if Tenant conducts
its own tests of the Premises using third party  contractors and test procedures
acceptable  to Landlord  which tests are certified to Landlord,  Landlord  shall
accept  such  tests in lieu of the  annual  tests to be paid for by  Tenant.  In
addition, at any time, and from time to time, prior to the expiration or earlier
termination of the Term,  Landlord  shall have the right to conduct  appropriate
tests of the Premises and the Project to determine if contamination has occurred
as a result of Tenant's use of the Premises.  In  connection  with such testing,
upon the request of Landlord, Tenant shall deliver to Landlord or its consultant
such non-proprietary information concerning the use of Hazardous Materials in or
about the Premises by Tenant or any Tenant Party. If contamination  has occurred
for which Tenant is liable under this Section 30,  Tenant shall pay all costs to
                                      ----------
conduct such tests. If no such  contamination  is found,  Landlord shall pay the
costs of such tests (which shall not constitute an Operating Expense).  Landlord
shall provide  Tenant with a copy of all third party,  non-confidential  reports
and  tests of the  Premises  made by or on behalf of  Landlord  during  the Term
without  representation or warranty and subject to a confidentiality  agreement.
Tenant  shall,  at its  sole  cost  and  expense,  promptly  and  satisfactorily
remediate any environmental  conditions identified by such testing in accordance
with all Environmental Requirements.  Landlord's receipt of or satisfaction with
any environmental assessment in no way waives any rights which Landlord may have
against Tenant.

     (e)  UNDERGROUND  TANKS.  If  underground  or other  storage  tanks storing
Hazardous Materials located on the Premises or the Project are used by Tenant or
are  hereafter  placed on the  Premises or the

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Project by Tenant,  Tenant  shall  install,  use,  monitor,  operate,  maintain,
upgrade and manage such storage tanks, maintain appropriate records,  obtain and
maintain appropriate insurance,  implement reporting procedures,  properly close
any underground  storage tanks,  and take or cause to be taken all other actions
necessary or required under applicable state and federal Legal Requirements,  as
such now exists or may  hereafter be adopted or amended in  connection  with the
installation, use, maintenance,  management, operation, upgrading and closure of
such storage tanks.

     (f) TENANT'S OBLIGATIONS.  Tenant's obligations under this Section 30 shall
                                                                        --------
survive the expiration or earlier termination of the Lease. During any period of
time after the  expiration  or earlier  termination  of this Lease  required  by
Tenant or Landlord to complete the removal  from the  Premises of any  Hazardous
Materials  (including,  without  limitation,  the release and termination of any
licenses or permits  restricting  the use of the Premises and the  completion of
the approved  Surrender  Plan),  Tenant  shall  continue to pay the full Rent in
accordance with this Lease for any portion of the Premises not relet by Landlord
in Landlord's sole discretion, which Rent shall be prorated daily.

     (g)  DEFINITIONS.  As used herein,  the term  "ENVIRONMENTAL  REQUIREMENTS"
means all  applicable  present  and future  statutes,  regulations,  ordinances,
rules, codes, judgments,  orders or other similar enactments of any Governmental
Authority regulating or relating to health, safety, or environmental  conditions
on, under, or about the Premises or the Project,  or the environment,  including
without limitation,  the following:  the Comprehensive  Environmental  Response,
Compensation and Liability Act; the Resource  Conservation and Recovery Act; and
all  state and local  counterparts  thereto,  and any  regulations  or  policies
promulgated or issued thereunder. As used herein, the term "HAZARDOUS MATERIALS"
means and includes any substance,  material,  waste,  pollutant,  or contaminant
listed or defined as hazardous or toxic, or regulated by reason of its impact or
potential   impact  on  humans,   animals  and/or  the  environment   under  any
Environmental Requirements,  asbestos and petroleum,  including crude oil or any
fraction thereof,  natural gas liquids,  liquefied natural gas, or synthetic gas
usable for fuel (or mixtures of natural gas and such synthetic  gas). As defined
in  Environmental  Requirements,  Tenant  is  and  shall  be  deemed  to be  the
"OPERATOR" of Tenant's  "FACILITY"  and the "OWNER" of all  Hazardous  Materials
brought  on the  Premises  by  Tenant  or any  Tenant  Party,  and  the  wastes,
by-products, or residues generated, resulting, or produced therefrom.

     30.  TENANT'S  REMEDIES/LIMITATION  OF LIABILITY.  Landlord shall not be in
default  hereunder  unless  Landlord  fails to  perform  any of its  obligations
hereunder  within 30 days after  written  notice  from  Tenant  specifying  such
failure  (unless such  performance  will,  due to the nature of the  obligation,
require a period of time in excess of 30 days, then after such period of time as
is reasonably necessary). Upon any default by Landlord, Tenant shall give notice
by  registered  or  certified  mail to any  Holder of a  Mortgage  covering  the
Premises  and to any  landlord  of any  lease of  property  in or on  which  the
Premises  are located  and Tenant  shall  offer such  Holder  and/or  landlord a
reasonable opportunity to cure the default,  including time to obtain possession
of the  Project  by power of sale or a  judicial  action  if such  should  prove
necessary to effect a cure;  provided Landlord shall have furnished to Tenant in
                             --------
writing the names and  addresses  of all such  persons  who are to receive  such
notices.  All obligations of Landlord hereunder shall be construed as covenants,
not  conditions;  and,  except as may be  otherwise  expressly  provided in this
Lease, Tenant may not terminate this Lease for breach of Landlord's  obligations
hereunder.

     All  obligations of Landlord under this Lease will be binding upon Landlord
only during the period of its ownership of the Premises and not thereafter.  The
term  "LANDLORD"  in this Lease  shall mean only the owner for the time being of
the  Premises.  Upon the transfer by such owner of its interest in the Premises,
such owner shall  thereupon be released and discharged  from all  obligations of
Landlord thereafter  accruing,  but such obligations shall be binding during the
Term upon each new owner for the duration of such owner's ownership.

     31. INSPECTION AND ACCESS. Subject to the following sentence,  Landlord and
its  agents,  representatives,  and  contractors  may enter the  Premises at any
reasonable  time to  inspect  the  Premises  and to make such  repairs as may be
required or permitted pursuant to this Lease and for any other business purpose.
Landlord and Landlord's  representatives  may enter the Premises during business
hours on not less than 48 hours advance  written  notice  (except in the case of
emergencies in which case

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no such  notice  shall be  required  and such  entry may be at any time) for the
purpose of effecting any such  repairs,  inspecting  the  Premises,  showing the
Premises to  prospective  purchasers  and,  during the last year of the Term, to
prospective  tenants or for any other business  purpose.  All such access to the
Premises shall be at times either agreed to by Tenant or that will not interfere
with Tenant  conducting its business.  Landlord may erect a suitable sign on the
Premises  stating  the  Premises  are  available  to let or that the  Project is
available  for sale.  Landlord  may grant  easements,  make public  dedications,
designate  Common  Areas  and  create  restrictions  on or about  the  Premises,
provided  that  no  such  easement,   dedication,   designation  or  restriction
--------
materially,  adversely affects Tenant's use or occupancy of the Premises for the
Permitted Use. At Landlord's  request,  Tenant shall execute such instruments as
may be necessary for such easements,  dedications or restrictions.  Tenant shall
at all  times,  except  in the case of  emergencies,  have the  right to  escort
Landlord or its agents,  representatives,  contractors  or guests while the same
are in the  Premises,  provided  such escort does not  materially  and adversely
affect Landlord's access rights hereunder.

     32.  SECURITY.  Tenant  acknowledges  and agrees that security  devices and
services,  if any,  while  intended  to deter  crime may not in given  instances
prevent  theft or other  criminal  acts and that  Landlord is not  providing any
security  services  with respect to the  Premises.  Tenant  agrees that Landlord
shall not be liable to Tenant for, and Tenant waives any claim against  Landlord
with respect to, any loss by theft or any other  damage  suffered or incurred by
Tenant in connection with any unauthorized  entry into the Premises or any other
breach  of  security  with  respect  to the  Premises.  Tenant  shall be  solely
responsible for the personal  safety of Tenant's  officers,  employees,  agents,
contractors,  guests and  invitees  while any such person is in, on or about the
Premises  and/or the  Project.  Tenant shall at Tenant's  cost obtain  insurance
coverage to the extent Tenant desires protection against such criminal acts.

     33. FORCE  MAJEURE.  Subject to the  limitation  set forth herein,  neither
Landlord nor Tenant shall be held  responsible  for delays in the performance of
its  obligations  hereunder when caused by strikes,  lockouts,  labor  disputes,
weather, natural disasters, inability to obtain labor or materials or reasonable
substitutes  therefor,  governmental  restrictions,   governmental  regulations,
governmental   controls,   delay  in  issuance  of  permits,  enemy  or  hostile
governmental action, civil commotion,  fire or other casualty,  and other causes
beyond the reasonable control of such party ("FORCE  MAJEURE").  This Section 32
shall not apply to Tenant's obligation to pay Rent.

     34.  BROKERS,  ENTIRE  AGREEMENT,   AMENDMENT.  Landlord  and  Tenant  each
represents  and warrants  that it has not dealt with any broker,  agent or other
person  (collectively,  "BROKER) in connection with this transaction and that no
Broker brought about this transaction.  Landlord and Tenant each hereby agree to
indemnify and hold the other harmless from and against any claims by any Broker,
other than the broker, if any named in this Section 35, claiming a commission or
                                            ----------
other form of compensation by virtue of having dealt with Tenant or Landlord, as
applicable, with regard to this leasing transaction.

     35. LIMITATION ON LANDLORD'S LIABILITY.  NOTWITHSTANDING ANYTHING SET FORTH
HEREIN OR IN ANY OTHER  AGREEMENT  BETWEEN  LANDLORD AND TENANT TO THE CONTRARY:
(A)  LANDLORD  SHALL NOT BE LIABLE TO TENANT OR ANY OTHER PERSON FOR (AND TENANT
AND EACH SUCH OTHER PERSON ASSUME ALL RISK OF) LOSS,  DAMAGE OR INJURY,  WHETHER
ACTUAL  OR  CONSEQUENTIAL  TO:  TENANT'S  PERSONAL  PROPERTY  OF EVERY  KIND AND
DESCRIPTION, INCLUDING, WITHOUT LIMITATION TRADE FIXTURES, EQUIPMENT, INVENTORY,
SCIENTIFIC  RESEARCH,  SCIENTIFIC  EXPERIMENTS,   LABORATORY  ANIMALS,  PRODUCT,
SPECIMENS, SAMPLES, AND/OR SCIENTIFIC, BUSINESS, ACCOUNTING AND OTHER RECORDS OF
EVERY KIND AND  DESCRIPTION  KEPT AT THE PREMISES AND ANY AND ALL INCOME DERIVED
OR DERIVABLE THEREFROM;  (B) THERE SHALL BE NO PERSONAL RECOURSE TO LANDLORD FOR
ANY ACT OR  OCCURRENCE  IN, ON OR ABOUT THE PREMISES OR ARISING IN ANY WAY UNDER
THIS LEASE OR ANY OTHER  AGREEMENT  BETWEEN  LANDLORD AND TENANT WITH RESPECT TO
THE SUBJECT  MATTER  HEREOF AND ANY  LIABILITY  OF LANDLORD  HEREUNDER  SHALL BE
STRICTLY  LIMITED  SOLELY TO LANDLORD'S  INTEREST IN THE

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PROJECT OR ANY  PROCEEDS  FROM SALE OR  CONDEMNATION  THEREOF AND ANY  INSURANCE
PROCEEDS  PAYABLE  IN  RESPECT  OF  LANDLORD'S  INTEREST  IN THE  PROJECT  OR IN
CONNECTION WITH ANY SUCH LOSS; AND (C) IN NO EVENT SHALL ANY PERSONAL  LIABILITY
BE  ASSERTED  AGAINST  LANDLORD  IN  CONNECTION  WITH  THIS  LEASE NOR SHALL ANY
RECOURSE BE HAD TO ANY OTHER PROPERTY OR ASSETS OF LANDLORD OR ANY OF LANDLORD'S
OFFICERS,  DIRECTORS,  EMPLOYEES, AGENTS OR CONTRACTORS.  UNDER NO CIRCUMSTANCES
SHALL LANDLORD OR ANY OF LANDLORD'S OFFICERS,  DIRECTORS,  EMPLOYEES,  AGENTS OR
CONTRACTORS BE LIABLE FOR INJURY TO TENANT'S  BUSINESS OR FOR ANY LOSS OF INCOME
OR PROFIT THEREFROM.

     36.  SEVERABILITY.  If any clause or  provision  of this Lease is  illegal,
invalid or  unenforceable  under present or future laws, then and in that event,
it is the intention of the parties hereto that the remainder of this Lease shall
not be affected  thereby.  It is also the intention of the parties to this Lease
that in lieu of each clause or provision of this Lease that is illegal,  invalid
or unenforceable, there be added, as a part of this Lease, a clause or provision
as  similar  in effect  to such  illegal,  invalid  or  unenforceable  clause or
provision as shall be legal, valid and enforceable.

     37. SIGNS; EXTERIOR APPEARANCE. Tenant shall not, without the prior written
consent of  Landlord,  which may be  granted  or  withheld  in  Landlord's  sole
discretion:  (i) attach any awnings,  exterior  lights,  decorations,  balloons,
flags,  pennants,  banners,  painting or other projection to any outside wall of
the  Project,  (ii) use any  curtains,  blinds,  shades or  screens  other  than
Landlord's  standard  window  coverings,  (iii) coat or otherwise  sunscreen the
interior or exterior of any windows,  (iv) place any bottles,  parcels, or other
articles on the window sills, (v) place any equipment,  furniture or other items
of personal property on any exterior balcony, or (vi) paint, affix or exhibit on
any part of the  Premises  or the  Project  any signs,  notices,  window or door
lettering, placards,  decorations, or advertising media of any type which can be
viewed  from the  exterior  of the  Premises.  Interior  signs on doors  and the
directory  tablet shall be inscribed,  painted or affixed for Tenant by Landlord
at the sole cost and expense of Tenant,  and shall be of a size,  color and type
acceptable to Landlord.  Nothing may be placed on the exterior of corridor walls
or corridor doors other than Landlord's standard lettering. The directory tablet
shall be  provided  exclusively  for the  display  of the name and  location  of
tenants.

     38. MISCELLANEOUS.

     (a) NOTICES. All notices or other communications  between the parties shall
be in writing and shall be deemed duly given upon  delivery or refusal to accept
delivery by the addressee thereof if delivered in person, or upon actual receipt
if delivered by reputable overnight guaranty courier,  addressed and sent to the
parties at their addresses set forth above. Landlord and Tenant may from time to
time by written  notice to the other  designate  another  address for receipt of
future notices.

     (b) JOINT AND  SEVERAL  LIABILITY.  If and when  included  within  the term
"TENANT," as used in this  instrument,  there is more than one person or entity,
each shall be jointly and severally liable for the obligations of Tenant.

     (c)  RECORDATION.  Neither  this Lease nor a  memorandum  of lease shall be
filed by or on behalf of Tenant in any public  record.  Landlord may prepare and
file, and upon request by Landlord Tenant will execute, a memorandum of lease.

     (d) INTERPRETATION.  The normal rule of construction to the effect that any
ambiguities are to be resolved  against the drafting party shall not be employed
in the interpretation of this Lease or any exhibits or amendments hereto.  Words
of any gender  used in this Lease  shall be held and  construed  to include  any
other  gender,  and words in the  singular  number  shall be held to include the
plural,  unless the context  otherwise  requires.  The captions inserted in this
Lease are for convenience only and in no way define, limit or otherwise describe
the scope or intent of this Lease, or any provision hereof, or in any way affect
the interpretation of this Lease.

     (e) NOT BINDING  UNTIL  EXECUTED.  The  submission by Landlord to Tenant of
this Lease shall have no binding force or effect, shall not constitute an option
for the leasing of the Premises,  nor confer any right or impose any obligations
upon either party until execution of this Lease by both parties.

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 24

     (f)  LIMITATIONS  ON INTEREST.  It is expressly  the intent of Landlord and
Tenant at all times to comply with  applicable law governing the maximum rate or
amount  of  any  interest  payable  on or in  connection  with  this  Lease.  If
applicable  law is ever  judicially  interpreted  so as to render  usurious  any
interest  called  for under this  Lease,  or  contracted  for,  charged,  taken,
reserved,  or received  with respect to this Lease,  then it is  Landlord's  and
Tenant's  express  intent  that all  excess  amounts  theretofore  collected  by
Landlord be credited on the  applicable  obligation  (or, if the  obligation has
been or would thereby be paid in full,  refunded to Tenant),  and the provisions
of this Lease  immediately  shall be deemed reformed and the amounts  thereafter
collectible hereunder reduced, without the necessity of the execution of any new
document,  so as to comply  with the  applicable  law,  but so as to permit  the
recovery of the fullest amount otherwise called for hereunder.

     (g) CHOICE OF LAW.  Construction and  interpretation of this Lease shall be
governed by the  internal  laws of the state in which the  Premises are located,
excluding any principles of conflicts of laws.

     (h)  TIME.  Time  is of the  essence  as to  the  performance  of  Tenant's
obligations under this Lease.

     (i)  INCORPORATION  BY REFERENCE.  All exhibits and addenda attached hereto
are hereby  incorporated into this Lease and made a part hereof. If there is any
conflict  between  such  exhibits or addenda  and the terms of this Lease,  such
exhibits or addenda shall control.

     (j)  HAZARDOUS  ACTIVITIES.  Notwithstanding  any other  provision  of this
Lease, Landlord, for itself and its employees, agents and contractors,  reserves
the right to refuse to perform  any  repairs or  services  in any portion of the
Premises which,  pursuant to Tenant's  routine safety  guidelines,  practices or
custom or prudent industry practices, require any form of protective clothing or
equipment  other than safety  glasses.  In any such case,  Tenant shall contract
with  parties  who  are  acceptable  to  Landlord,   in  Landlord's   reasonable
discretion, for all such repairs and services, and Landlord shall, to the extent
required,  equitably  adjust Tenant's Share of Operating  Expenses in respect of
such repairs or services to reflect that Landlord is not providing  such repairs
or services to Tenant.

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 25

         IN WITNESS WHEREOF,  Landlord and Tenant have executed this Lease as of
the day and year first above written.

                                     TENANT:

                                     CALYPTE BIOMEDICAL CORPORATION,
                                     a Delaware corporation

                                     By:   /s/ Richard D. Brounstein
                                           -------------------------
                                     Its:  EVP and CFO
                                           -----------


                                    LANDLORD:

                                    ARE-1500 EAST GUDE, LLC,
                                    a Delaware limited liability company

                                    By:    ARE-QRS CORP.,
                                           a Maryland corporation,
                                           managing member

                                           By:    /s/ Joel S. Marcus
                                                  ------------------
                                                  CEO

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 1

                               EXHIBIT A TO LEASE

                             DESCRIPTION OF PREMISES
                             -----------------------

[Illustration of 1500 EAST GUDE DRIVE - SECOND FLOOR]

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 1

                               EXHIBIT B TO LEASE

                             DESCRIPTION OF PROJECT
                             ----------------------

                                LEGAL DESCRIPTION

All  that  lot or  parcel  of land  located  in the  4th  Election  District  of
Montgomery County, Maryland and described as follows:

Parcel I:

Lot numbered  Five (5) in Block  lettered "A" in the  subdivision  known as "Red
Gate  Industrial  Park" as per plat  thereof  recorded  in Plat Book 102 at Plat
11503, among the Land Records of Montgomery County, Maryland.

Parcel I.D. No.: 4-201-1762126

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 1

                               EXHIBIT C TO LEASE

                                 [Tenant Build]

                                   WORK LETTER
                                   -----------

     THIS WORK LETTER  dated  March __,  2004 (this  "WORK  LETTER") is made and
entered  into by and  between  ARE-East  Gude  Lease,  LLC, a  Delaware  limited
liability company ("LANDLORD"),  and Calypte Biomedical Corporation,  a Delaware
corporation  ("TENANT"),  and is  attached to and made a part of the Lease dated
March 1, 2004 (the "Lease"),  by and between Landlord and Tenant.  Any initially
capitalized terms used but not defined herein shall have the meanings given them
in the Lease.

     1. GENERAL REQUIREMENTS.

(a) TENANT'S  AUTHORIZED  REPRESENTATIVE.  Tenant designates Thomas Callanan and
Richard   Brounstein   (either   such   individual   acting   alone,   "TENANT'S
REPRESENTATIVE")  as the only persons  authorized to act for Tenant  pursuant to
this Work Letter.  Landlord shall not be obligated to respond to or act upon any
request, approval,  inquiry or other communication  ("COMMUNICATION") from or on
behalf of Tenant in connection  with this Work Letter unless such  Communication
is in writing from Tenant's  Representative.  Tenant may change either  Tenant's
Representative  at any time upon not less than 5 business  days advance  written
notice to Landlord. No period set forth herein for any approval of any matter by
Tenant's  Representative  shall be  extended by reason of any change in Tenant's
Representative.  Neither Tenant nor Tenant's  Representative shall be authorized
to direct  Landlord's  contractors  in the  performance  of Landlord's  Work (as
hereinafter defined).

     (b) LANDLORD'S AUTHORIZED  REPRESENTATIVE.  Landlord designates Lawrence J.
Diamond and Oliver Sherrill  (either such individual  acting alone,  "LANDLORD'S
REPRESENTATIVE")  as the only persons authorized to act for Landlord pursuant to
this Work  Letter.  Tenant  shall not be obligated to respond to or act upon any
request,  approval, inquiry or other Communication from or on behalf of Landlord
in connection with this Work Letter unless such Communication is in writing from
Landlord's Representative.  Landlord may change either Landlord's Representative
at any time upon not less than 5 business days advance written notice to Tenant.
No  period  set forth  herein  for any  approval  of any  matter  by  Landlord's
Representative  shall  be  extended  by  reason  of  any  change  in  Landlord's
Representative.  Landlord's  Representative shall be the sole persons authorized
to direct Landlord's contractors in the performance of Landlord's Work.

     (c)  ARCHITECTS,  CONSULTANTS AND  CONTRACTORS.  Landlord and Tenant hereby
acknowledge  and agree that the architect  (the "TI  ARCHITECT")  for the Tenant
Improvements,  the  general  contractor  and any  subcontractors  for the Tenant
Improvements shall be selected by Tenant, subject to Landlord's approval,  which
approval shall not be unreasonably withheld, conditioned or delayed.

     2. TENANT IMPROVEMENTS.

     (a) TENANT  IMPROVEMENTS  DEFINED.  As used herein,  "TENANT  IMPROVEMENTS"
shall mean all  improvements  to the  Premises  desired by Tenant of a fixed and
permanent  nature.  Other than  funding the TI Allowance  (as defined  below) as
provided herein,  Landlord shall not have any obligation whatsoever with respect
to the finishing of the Premises for Tenant's use and occupancy.

     (b)  TENANT'S  SPACE  PLANS.  Tenant  shall  deliver to Landlord  schematic
drawings  and  outline  specifications  (the  "TI  DESIGN  DRAWINGS")  detailing
Tenant's requirements for the Tenant Improvements within 15 business days of the
date  hereof.  Not more than ten 10 business  days  thereafter,  Landlord  shall
deliver to Tenant the written objections,  questions or comments of Landlord and
the TI Architect with regard to the TI Design  Drawings.  Tenant shall cause the
TI Design  Drawings to be revised to address  such  written  comments  and shall
resubmit  said  drawings  to  Landlord  for  approval  within 10  business  days
thereafter.  Such  process  shall  continue  until  Landlord has approved the TI
Design Drawings.

                  (C) All rights reserved - Alexandria Real Estate Equities 2001
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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 2

     (c)  WORKING  DRAWINGS.  Not later  than 15  business  days  following  the
approval  of the TI Design  Drawings  by  Landlord,  Tenant  shall  cause the TI
Architect to prepare and deliver to Landlord for review and comment construction
plans, specifications and drawings for the Tenant Improvements ("TI CONSTRUCTION
DRAWINGS"),  which TI Construction  Drawings shall be prepared  substantially in
accordance with the TI Design Drawings.  Tenant shall be solely  responsible for
ensuring that the TI Construction Drawings reflect Tenant's requirements for the
Tenant  Improvements.  Landlord  shall  deliver its  written  comments on the TI
Construction Drawings to Tenant not later than 10 business days after Landlord's
receipt of the same;  provided,  however,  that Landlord may not  disapprove any
matter  that is  consistent  with  the TI  Design  Drawings.  Tenant  and the TI
Architect  shall  consider all such comments in good faith and shall,  within 10
business days after receipt,  notify  Landlord how Tenant proposes to respond to
such comments.  Any disputes in connection  with such comments shall be resolved
in accordance  with Section 2(d) hereof.  Provided that the design  reflected in
                    -----------
the TI Construction Drawings is consistent with the TI Design Drawings, Landlord
shall approve the TI Construction Drawings submitted by Tenant. Once approved by
Landlord,  subject to the  provisions  of Section  2(d) below,  Tenant shall not
                                          ------------
materially  modify  the TI  Construction  Drawings  except as may be  reasonably
required in connection with the issuance of the TI Permit (as defined in Section
                                                                         -------
3(b) below).
---

     (d) APPROVAL AND COMPLETION.  Upon any dispute  regarding the design of the
Tenant  Improvements,  which is not settled within 10 business days after notice
of such dispute is delivered by one party to the other, and except to the extent
the  proposed  Tenant  Improvements  would  adversely  impact the base  Building
structure or the Building  Systems,  in which case Landlord shall make the final
decision regarding the design of such Tenant Improvements, Tenant shall make the
final decision regarding the design of the Tenant Improvements,  provided Tenant
acts  reasonably  and  such  final  decision  is  either  consistent  with  or a
compromise  between  Landlord's  and  Tenant's  positions  with  respect to such
dispute,  provided  further that all costs and expenses  resulting from any such
decision  by Tenant  shall be payable  out of the TI Fund (as defined in Section
                                                                         -------
5(d) below). Any changes to the TI Construction  Drawings  following  Landlord's
---
and Tenant's approval of same requested by Tenant shall be processed as provided
in Section 4 hereof.
   ---------

     3. PERFORMANCE OF TENANT'S WORK.

     (a) DEFINITION OF TENANT'S WORK. As used herein, "TENANT'S WORK" shall mean
the work of constructing the Tenant Improvements.

     (b)  COMMENCEMENT  AND PERMITTING OF TENANT'S  WORK.  Tenant shall commence
construction  of the Tenant  Improvements  upon obtaining a building permit (the
"TI PERMIT") authorizing the construction of the Tenant Improvements  consistent
with the TI Construction  Drawings approved by Landlord and delivering a copy of
the TI Permit to Landlord.  The cost of obtaining the TI Permit shall be payable
from the TI Fund. Landlord shall assist Tenant in obtaining the TI Permit. Prior
to the  commencement of  construction of Tenant's Work,  Tenant shall deliver to
Landlord a fully  executed  copy of  Tenant's  contract  with  Tenant's  general
contractor and a copy of such general  contractor's  certificate of insurance or
policy endorsement naming Landlord and any of Landlord's  nominees as additional
insureds.

     (c)  SELECTION OF MATERIALS,  ETC.  Where more than one type of material or
structure is indicated on the TI  Construction  Drawings  approved by Tenant and
Landlord,  the option will be within Tenant's reasonable  discretion,  except to
the extent the proposed  material or structure would  adversely  impact the base
Building  structure or the Building  Systems,  in which case Landlord shall make
the final decision at its discretion.

     4.  CHANGES.  Any changes  requested  by Tenant to the Tenant  Improvements
after the delivery and approval by Landlord of the TI Design Drawings,  shall be
requested and instituted in accordance with the provisions of this Section 4 and
                                                                   ---------
shall be subject to the written  approval of Landlord,  such  approval not to be
unreasonably withheld, conditioned or delayed.

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 3

     (a) TENANT'S  RIGHT TO REQUEST  CHANGES.  If Tenant shall  request  changes
("CHANGES"),  Tenant shall request such Changes by notifying Landlord in writing
in substantially  the same form as the AIA standard change order form (a "CHANGE
REQUEST"),  which Change  Request shall detail the nature and extent of any such
Change. Such Change Request must be signed by Tenant's Representative.  Landlord
shall review and approve or  disapprove  such Change  Request  within 5 business
days  thereafter,  provided that  Landlord's  approval shall not be unreasonably
withheld, conditioned or delayed.

     (b) IMPLEMENTATION OF CHANGES.  If Landlord approves such Change and Tenant
deposits  with  Landlord  any Excess TI Costs (as defined in Section 5(d) below)
                                                             -----------
required in connection with such Change, Tenant may cause the approved Change to
be instituted.

     5. COSTS.

     (a) BUDGET FOR TENANT IMPROVEMENTS. Before the commencement of construction
of the Tenant Improvements, Tenant shall prepare a detailed breakdown, by trade,
of the costs incurred or which will be incurred,  in connection  with the design
and  construction  of  Tenant's  Work (the  "BUDGET")  and deliver a copy of the
Budget to Landlord.  The Budget shall be based upon the TI Construction Drawings
approved by Landlord and shall  include a payment to Landlord of  administrative
rent  in an  amount  equal  to  $5,000  ("ADMINISTRATIVE  RENT")  to be  used to
reimburse Landlord for any actual out-of-pocket expenses incurred by Landlord in
monitoring and inspecting the  construction of Tenant's Work, which sum shall be
payable  from the TI Fund.  Such  Administrative  Rent  shall  include,  without
limitation,  all out-of-pocket costs, expenses and fees incurred by or on behalf
of Landlord  arising from, out of, or in connection with, such monitoring of the
construction  of the Tenant  Improvements,  and shall be  payable  out of the TI
Fund. If the Budget is greater than the TI Allowance,  Tenant shall deposit with
Landlord the difference,  in cash,  prior to the commencement of construction of
the Tenant  Improvements,  for  disbursement by Landlord as described in Section
                                                                         -------
5(d).
---

     (b) Landlord  shall provide to Tenant a tenant  improvement  allowance ("TI
ALLOWANCE") of $10.00 per rentable square foot of the Premises. The Budget shall
reflect how much TI Allowance Tenant has elected to receive from Landlord.  Such
election  shall be final  and  binding  on  Tenant,  and may not  thereafter  be
modified  without  Landlord's  consent,  which may be  granted  or  withheld  in
Landlord's sole and absolute discretion.  The TI Allowance shall be disbursed in
accordance with this Work Letter.

     Tenant  shall  have no right to the use or  benefit  of any  portion of the
Tenant Improvement Allowance not required for the construction of (i) the Tenant
Improvements  described in the TI  Construction  Drawings  approved  pursuant to
Section 2(d) or (ii) any Changes pursuant to Section 4.

     (c) COSTS  INCLUDABLE IN TI FUND.  The TI Fund shall be used solely for the
payment of design and construction  costs in connection with the construction of
the Tenant Improvements,  including,  without limitation,  the cost of preparing
the TI Design Drawings and the TI Construction  Drawings, all costs set forth in
the Budget,  including  Landlord's  Administrative Rent, and the cost of Changes
(collectively,  "TI COSTS").  Notwithstanding anything to the contrary contained
herein,  the TI Fund  shall  not be used to  purchase  any  furniture,  personal
property or other non-Building System materials or equipment, including, but not
be limited to,  biological  safety cabinets and other  scientific  equipment not
incorporated into the Improvements.

     (d) EXCESS TI COSTS.  It is understood and agreed that Landlord is under no
obligation  to bear any  portion of the cost of any of the  Tenant  Improvements
except to the extent of the TI Allowance.

     (e) PAYMENT FOR TI COSTS.  Landlord shall pay TI Costs once a month against
a draw request in Landlord's standard form, containing such certifications, lien
waivers,  inspection reports and other matters as Landlord  customarily obtains,
to the extent of Landlord's  approval thereof for payment, no later than 30 days
following  receipt  of  such  draw  request.   Upon  completion  of  the  Tenant
Improvements and prior to Landlord's funding of the final draw from the TI Fund,
Tenant shall deliver to Landlord:  (i) sworn statements  setting forth the names
of all contractors and subcontractors  who did the work and final  unconditional
lien  waivers  from all such  contractors  and  subcontractors;  (ii) "as built"
plans,

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 4

in both print and electronic format, and copies of all operating and maintenance
manuals and warranties, as applicable, for such Tenant Improvements; and (iii) a
certificate of occupancy.

     6. MISCELLANEOUS.

     (a)  CONSENTS.  Whenever  consent or approval  of either  party is required
under this Work Letter, that party shall not unreasonably withhold, condition or
delay such consent or approval,  except as may be expressly  set forth herein to
the contrary.

     (b) MODIFICATION. No modification,  waiver or amendment of this Work Letter
or of any of its  conditions  or  provisions  shall be binding upon  Landlord or
Tenant unless in writing signed by Landlord and Tenant.

     (c)  COUNTERPARTS.  This  Work  Letter  may be  executed  in any  number of
counterparts  but all  counterparts  taken  together  shall  constitute a single
document.

     (d)  GOVERNING  LAW.  This Work Letter shall be governed by,  construed and
enforced in accordance with the internal laws of the state in which the Premises
are located, without regard to choice of law principles of such State.

     (e) TIME OF THE ESSENCE.  Time is of the essence of this Work Letter and of
each and all provisions thereof.

     (f) DEFAULT.  Notwithstanding  anything set forth herein or in the Lease to
the  contrary,  Landlord  shall  not have any  obligation  to  perform  any work
hereunder  or to fund any portion of the TI Fund during any period  Tenant is in
Default under the Lease.

     (g) SEVERABILITY.  If any term or provision of this Work Letter is declared
invalid  or  unenforceable,  the  remainder  of this  Work  Letter  shall not be
affected by such determination and shall continue to be valid and enforceable.

     (h) MERGER. All understandings and agreements,  oral or written, heretofore
made between the parties hereto and relating to Tenant's Work are merged in this
Work Letter,  which alone (but inclusive of provisions of the Lease incorporated
herein and the final approved constructions drawings and specifications prepared
pursuant hereto) fully and completely  expresses the agreement  between Landlord
and Tenant with regard to the matters set forth in this Work Letter.

     (i) ENTIRE AGREEMENT. This Work Letter is made as a part of and pursuant to
the Lease and, together with the Lease,  constitutes the entire agreement of the
parties with respect to the subject matter  hereof.  This Work Letter is subject
to all of the terms and  limitation  set forth in the Lease,  and neither  party
shall have any rights or remedies under this Work Letter separate and apart from
their respective remedies pursuant to the Lease.

                           [SIGNATURES ON NEXT PAGE]

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 5

     IN WITNESS  WHEREOF,  Landlord and Tenant have executed this Work Letter to
be effective on the date first above written.

                                     TENANT:

                                     CALYPTE BIOMEDICAL CORPORATION,
                                     a Delaware corporation

                                     By:  /s/ Richard D.Brounstein
                                          --------------------------------------
                                     Its: EVP and CFO
                                          --------------------------------------


                                    LANDLORD:

                                    ARE-1500 EAST GUDE, LLC,
                                    a Delaware limited liability company

                                    By:  ARE-QRS CORP.,
                                         a Maryland corporation,
                                         managing member

                                         By:  /s/ Joel S. Martin
                                              ----------------------------------
                                              CEO

                  (C) All rights reserved - Alexandria Real Estate Equities 2001
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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 1

                               EXHIBIT E TO LEASE

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

     1. The  sidewalk,  entries,  and  driveways  of the  Project  shall  not be
obstructed by Tenant, or any Tenant Party, or used by them for any purpose other
than ingress and egress to and from the Premises.

     2.  Tenant  shall  not  place  any  objects,  including  antennas,  outdoor
furniture,  etc., in the parking areas,  landscaped areas or other areas outside
of its Premises, or on the roof of the Project.

     3. Except for animals  assisting the disabled,  no animals shall be allowed
in the offices, halls, or corridors in the Project.

     4.  Tenant  shall not  disturb the  occupants  of the Project or  adjoining
buildings by the use of any radio or musical instrument or by the making of loud
or improper noises.

     5. If Tenant desires telegraphic,  telephonic or other electric connections
in the Premises,  Landlord or its agent will direct the  electrician as to where
and how the wires may be introduced;  and, without such direction,  no boring or
cutting of wires will be permitted. Any such installation or connection shall be
made at Tenant's expense.

     6.  Tenant  shall not install or operate any steam or gas engine or boiler,
or other mechanical apparatus in the Premises,  except as specifically  approved
in the Lease. The use of oil, gas or inflammable  liquids for heating,  lighting
or any other  purpose is  expressly  prohibited.  Explosives  or other  articles
deemed extra hazardous shall not be brought into the Project.

     7. Parking any type of recreational vehicles is specifically  prohibited on
or about the Project. Except for the overnight parking of operative vehicles, no
vehicle of any type  shall be stored in the  parking  areas at any time.  In the
event that a vehicle is  disabled,  it shall be removed  within 48 hours.  There
shall be no "For  Sale"  or other  advertising  signs  on or  about  any  parked
vehicle.  All  vehicles  shall be  parked  in the  designated  parking  areas in
conformity with all signs and other markings.  All parking will be open parking,
and no reserved  parking,  numbering or lettering of  individual  spaces will be
permitted except as specified by Landlord.

     8. Tenant shall maintain the Premises free from rodents,  insects and other
pests.

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

     10.  Tenant  shall not cause any  unnecessary  labor by reason of  Tenant's
carelessness or indifference in the  preservation of good order and cleanliness.
Landlord  shall not be  responsible  to Tenant for any loss of  property  on the
Premises,  however occurring, or for any damage done to the effects of Tenant by
the janitors or any other employee or person.

     11. Tenant shall give  Landlord  prompt notice of any defects in the water,
lawn  sprinkler,  sewage,  gas pipes,  electrical  lights and fixtures,  heating
apparatus, or any other service equipment affecting the Premises.

     12. Tenant shall not permit storage outside the Premises, including without
limitation, outside storage of trucks and other vehicles, or dumping of waste or
refuse or permit any harmful  materials to be placed in any  drainage  system or
sanitary system in or about the Premises.

                  (C) All rights reserved - Alexandria Real Estate Equities 2001
                                        CONFIDENTIAL - DO NOT COPY OR DISTRIBUTE

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 2

     13. All moveable trash receptacles  provided by the trash disposal firm for
the Premises must be kept in the trash  enclosure  areas,  if any,  provided for
that purpose.

     14. No auction, public or private, will be permitted on the Premises or the
Project.

     15. No awnings shall be placed over the windows in the Premises except with
the prior written consent of Landlord.

     16. The Premises shall not be used for lodging,  sleeping or cooking or for
any immoral or illegal  purposes or for any purpose other than that specified in
the Lease. No gaming devices shall be operated in the Premises.

     17. Tenant shall  ascertain  from Landlord the maximum amount of electrical
current  which can  safely be used in the  Premises,  taking  into  account  the
capacity of the electrical  wiring in the Project and the Premises and the needs
of other  tenants,  and shall not use more than such safe  capacity.  Landlord's
consent to the installation of electric  equipment shall not relieve Tenant from
the obligation not to use more electricity than such safe capacity.

     18. Tenant  assumes full  responsibility  for  protecting the Premises from
theft, robbery and pilferage.

     19.  Tenant shall not install or operate on the  Premises any  machinery or
mechanical  devices of a nature not directly related to Tenant's ordinary use of
the Premises and shall keep all such machinery free of vibration,  noise and air
waves which may be transmitted beyond the Premises.

                  (C) All rights reserved - Alexandria Real Estate Equities 2001
                                        CONFIDENTIAL - DO NOT COPY OR DISTRIBUTE

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NET/MULTI-TENANT OFFICE/LABORATORY          1500 EAST GUDE DRIVE/CALYPTE-PAGE 1

                               EXHIBIT F TO LEASE

                           TENANT'S PERSONAL PROPERTY
                           --------------------------

None except as set forth below: