Document:

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                                                                   EXHIBIT 10.1

                             FOURTH AMENDMENT TO THE
                             INVITROGEN CORPORATION
                             1997 STOCK OPTION PLAN

         Pursuant to Section 12 of the Invitrogen Corporation 1997 Stock Option
Plan, as amended (the "Plan"), a new Section 3.3(j) is hereby added to the Plan,
to state in its entirety as follows:

                  "(j) to delegate the power to grant Options to any Employee or
         Consultant who is not a Director, Insider, or other officer of the
         Company in an amount not to exceed options to purchase 25,000 shares of
         Stock (subject to adjustment to reflect changes in capital structure
         covered by Section 4.2 below); PROVIDED that any such grant shall be
         made only in accordance with a Stock Option Program or other program,
         plan, or procedure approved by the Board.<PAGE>

                                                                  Exhibit 10.10

            [LOGO] AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION

          STANDARD INDUSTRIAL/COMMERCIAL SINGLE-TENANT LEASE-NET
             (DO NOT USE THIS FORM FOR MULTI-TENANT PROPERTY)

1. BASIC PROVISIONS ("BASIC PROVISIONS")

    1.1 PARTIES: This Lease ("LEASE"), dated for reference purposes only,
October 7, 1999, is made by and between BLACKMORE SIGNAL HILL, A CALIFORNIA
LIMITED PARTNERSHIP ("LESSOR") and INVITROGEN CORPORATION ("LESSEE"),
(collectively the "PARTIES," or individually a "PARTY").

    1.2 PREMISES: That certain real property, including all improvements therein
or to be provided by Lessor under the terms of this Lease, and commonly known by
the street address of 1620 Faraday Avenue, located in the County of San Diego,
State of California, and generally described as (described briefly the nature of
the property) The approximately 28,411 square foot concrete tilt up industrial
Research and Development building to be constructed on Lot 98 of the Carlsbad
Research Center (approximately 2,079 acres) including 108 on-site parking spaces
conforming to Exhibit E ("PREMISES"). (See Paragraph 2 for further provisions.)

    1.3 TERM: Ten (10) years and six (6) months ("ORIGINAL TERM") commencing *
("COMMENCEMENT DATE") and ending September 30, 2010 ("EXPIRATION DATE").
(See Paragraph 3 for further provisions.)

    1.4 EARLY POSSESSION: see also Paragraph 49 ("EARLY POSSESSION DATE").
(See Paragraphs 3.2 and 3.3 for further provisions.)

    1.5 BASE RENT: $24,000.00 per month ("BASE RENT"), payable on the first
(1st) day of each month commencing on the Commencement Date. (See Paragraph 4
for further provisions.)

[x] If this box is checked, there are provisions in this Lease for the Base Rent
to be adjusted.

    1.6 BASE RENT PAID UPON EXECUTION: $12,000.00 as Base Rent for the period
June 16-30, 2000.

    1.7 SECURITY DEPOSIT: $30,000.00 ("SECURITY DEPOSIT"). (See Paragraph
5 for further provisions.)

    1.8 PERMITTED USE: General office use and all other uses permitted under
applicable laws, regulations, covenants, conditions, and restrictions
governing. (See Paragraph 6 for further provisions.)

    1.9 INSURING PARTY: Lessor is the "INSURING PARTY" unless otherwise
stated herein. (See Paragraph 8 for further provisions.)

    1.11 GUARANTOR. The obligations of the Lessee under this Lease are to be
guaranteed by N/A ("GUARANTOR"). (See Paragraph 37 for further provisions.)

    1.12 ADDENDA. Attached hereto is an Addendum consisting of Paragraphs 49
through 57 and Exhibits A-E all of which constitute a part of this Lease.

2. PREMISES:

   2.1 LETTING. Lessor hereby leases to Lessee, and Lessee hereby leases from
Lessor, the Premises, for the term, at the rental, and upon all of the terms,
covenants and conditions set forth in this Lease. Unless otherwise provided
herein, any statement of square footage set forth in this Lease, or that may
have been used in calculating rental, is an approximation which Lessor and
Lessee agree is reasonable and the rental based thereon is not subject to
revision whether or not the actual square footage is more or less.

   2.2 CONDITION. Lessor shall deliver the Premises to Lessee clean and free
of debris on the Commencement Date and warrants to Lessee that the existing
plumbing, fire sprinkler system, lighting, air conditioning, heating, and
loading doors, if any, in the Premises, other than those constructed by
Lessor shall, except as otherwise provided in this Lease, promptly after
receipt of written notice from Lessee setting forth with specificity the
nature and extent of such non-compliance, rectify same at Lessor's expense.
If Lessee does not give Lessor written notice of a non-compliance with this
warranty within one hundred eighty (180) days after the Commencement Date,
correction of that non-compliance shall be the obligation of Lessee at
Lessee's sole cost and expense.

   2.3 COMPLIANCE WITH COVENANTS, RESTRICTIONS AND BUILDING CODE. Lessor
warrants to Lessee that the improvements on the Premises comply with all
applicable covenants or restrictions of record and applicable building codes,
regulations and ordinances in effect on the Commencement Date. Said warranty
does not apply to the use to which Lessee will put the Premises or to any
Alterations or Utility Installations (as defined in Paragraph 7.3(a)) made or
to be made by Lessee. If the Premises do not comply with said warranty,
Lessor shall, except as otherwise provided in this Lease, promptly after
receipt of written notice from Lessee setting forth with specificity the
nature and extent of such non-compliance, rectify the same at Lessor's
expense; such warranty shall expire six (6) months following the Commencement
Date.

   2.4 ACCEPTANCE OF PREMISES. Lessee hereby acknowledges: (a) that it has been
advised to satisfy itself with respect to the condition of the Premises and the
present and future suitability of the Premises for Lessee's intended use, (b)
that Lessee has made such Investigation* as it deems necessary with reference to
such matters and assumes all responsibility therefor as the same relate to
Lessee's occupancy of the Premises and/or the term of this Lease, and (c) that
neither Lessor, nor any of Lessor's agents, has made any oral or written
representations or warranties with respect to the said matters other than as set
forth in this Lease.

* of the present condition and suitability of the Premises.

3. TERM.

   3.1 TERM. The Commencement Date, Expiration Date and Original Term of this
Lease are as specified in Paragraph 1.3.

   3.2 EARLY POSSESSION. If Lessee totally or partially occupies the Premises
prior to the Commencement Date, the obligation to pay Base Rent shall be
abated for the period of such early possession. All other terms of this
Lease, however, (including but not limited to the obligations to pay Real
Property Taxes and insurance premiums and to maintain the Premises) shall be
in effect during such period. Any such early possession shall not affect nor
advance the Expiration Date of the Original Term.

* That date which is twelve (12) weeks following the Date of Substantial
  Completion of the Shell Building (as defined in Exhibit B). Anticipated Date
  of Substantial Completion of the Shell Building is February 15, 2000 and the
  corresponding commencement date would be May 15, 2000 subject to adjustment as
  described in Exhibit B.

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   3.3 DELAY IN POSSESSION. If for any reason Lessor cannot deliver
possession of the Premises to Lessee as agreed herein by the Early Possession
Date, if one is specified in Paragraph 1.4, or, if no Early Possession Date
is specified, by the Commencement Date, Lessor shall not be subject to any
liability therefor, nor shall such failure affect the validity of this Lease,
or the obligations of Lessee hereunder, or extend the term hereof, but in
such case, Lessee shall not, except as otherwise provided herein, be
obligated to pay rent or perform any other obligation of Lessee under the
terms of this Lease until Lessor delivers possession of the Premises to
Lessee. If possession of the Premises is not delivered to Lessee, Lessee may,
at its option, by notice in writing to Lessor within thirty (30) days
thereafter, cancel this Lease, in which event the Parties shall be discharged
from all obligations hereunder; provided, however, that if such written
notice by Lessee is not received by Lessor within said thirty (30) day
period, Lessee's right to cancel this Lease shall terminate and be of no
further force or effect. Except as may be otherwise provided, and regardless
of when the term actually commences, if possession is not tendered to Lessee
when required by this Lease and Lessee does not terminate this Lease, as
aforesaid, the period free of the obligation to pay Base Rent, if any, that
Lessee would otherwise have enjoyed shall run from the date of delivery of
possession and continue for a period equal to what Lessee would otherwise
have enjoyed under the terms hereof, but minus any days of delay caused by
the acts, changes or omissions of Lessee.

4. RENT.

   4.1 BASE RENT. Lessee shall cause payment of Base Rent and other rent or
changes, as the same may be adjusted from time to time, to be received by Lessor
in lawful money of the United States, without offset or deduction, on or before
the day on which it is due under the terms of this Lease. Base Rent and all
other rent and charges for any period during the term hereof which is for less
than one (1) full calendar month shall be prorated based upon the actual number
of days of the calendar month involved. Payment of Base Rent and other charges
shall be made to Lessor at its address stated herein or to such other persons or
at such other addresses as Lessor may from time to time designate in writing to
Lessee.

5. SECURITY DEPOSIT. Lessee shall deposit with Lessor upon execution hereof
the Security Deposit set forth in Paragraph 1.7 as security for Lessee's
faithful performance of Lessee's obligations under this Lease. If Lessee fails
to pay Base Rent or other rent or charges due hereunder, or otherwise Defaults
under this Lease (as defined in Paragraph 13.1), Lessor may use, apply or retain
all or any portion of said Security Deposit for the payment of any amount due
Lessor or to reimburse or compensate Lessor for any liability, cost, expense,
loss or damage (including attorneys' fees) which Lessor may suffer or incur by
reason thereof. If Lessor uses or applies all or any portion of said Security
Deposit, Lessee shall within (10) days after written request therefor deposit
moneys with Lessor sufficient to restore said Security Deposit to the full
amount required by this Lease. Lessor shall not be required to keep all or any
part of the Security Deposit separate from its general accounts. Lessor shall,
at the expiration or earlier termination of the term hereof and after Lessee has
vacated the Premises, return to Lessee (or, at Lessor's option, to the last
assignee, if any, of Lessee's interest herein), that portion of the Security
Deposit not used or applied by Lessor. Unless otherwise expressly agreed in
writing by Lessor, no part of the Security Deposit shall be considered to be
held in trust, to bear interest or other increment for its use, or to be
prepayment for any moneys to be paid by Lessee under this Lease.

6. USE.

   6.1 USE. Lessee shall use and occupy the Premises only for the purposes set
forth in Paragraph 1.8, or any other use which is comparable thereto, and for no
other purpose. Lessee shall not use or permit the use of the Premises in a
matter that creates waste or a nuisance, or that disturbs owners and/or
occupants of, or causes damage to, neighboring premises or properties.

   6.2 HAZARDOUS SUBSTANCES.

       (a) REPORTABLE USES REQUIRE CONSENT. The term "HAZARDOUS SUBSTANCE" as
used in this Lease shall mean any product, substance, chemical, material or
waste whose presence, nature, quantity and/or intensity of existence, use,
manufacture, disposal, transportation, spill, release or effect, either by
itself or in combination with other materials expected to be on the Premises, is
either: (ii) regulated or monitored by any governmental authority, or (iii) a
basis for liability of Lessor to any governmental agency or third party under
any applicable statute or common law theory. Hazardous Substance shall include,
but not be limited to, hydrocarbons, petroleum, gasoline, crude oil or any
products, by-products or fractions thereof. Lessee shall not engage in any
activity in, on or about the Premises which constitutes a Reportable Use (as
hereinafter defined) of Hazardous Substances without the express prior written
consent of Lessor and compliance in a timely manner (at Lessee's sole cost and
expense) with all Applicable Law (as defined in Paragraph 6.3). "REPORTABLE USE"
shall mean (i) the installation or use of any above or below ground storage
tank, (ii) the generation, possession, storage, use, transportation, or disposal
of a Hazardous Substance that requires a permit from, or with respect to which a
report, notice, registration or business plan is required to be filed with, any
governmental authority. Reportable Use shall also include Lessee's being
responsible for the presence in, on or about the Premises of a Hazardous
Substance with respect to which any Applicable Law requires that a notice be
given to persons entering or occupying the Premises or neighboring properties.
Notwithstanding the foregoing, Lessee may, without Lessor's prior consent, but
in compliance with all Applicable Law, use any ordinary and customary materials
reasonably required to be used by Lessee in the normal course of Lessee's
business permitted on the Premises, so long as such use is not a Reportable Use
and does not expose the Premises or neighboring properties to any meaningful
risk of contamination or damage or expose Lessor to any liability therefor. In
addition, Lessor may (but without any obligation to do so) condition its consent
to the use or presence of any Hazardous Substance, activity or storage tank by
Lessee upon Lessee's giving Lessor such additional assurances as Lessor, in its
reasonable discretion, deems necessary to protect itself, the public, the
Premises and the environment against damage, contamination or injury and/or
liability therefrom or therefor, including, but not limited to, the installation
(and removal on or before Lease expiration or earlier termination) of reasonably
necessary protective modifications to the Premises (such as concrete
encasements) and/or the deposit of an additional Security Deposit under
Paragraph 5 hereof. Lessor consents to the use of the Hazardous Substances
listed on Exhibit D conditioned upon Lessee's compliance with the provisions
of Section 6.

        (b) DUTY TO INFORM LESSOR. If Lessee knows, or has reasonable cause
to believe, that a Hazardous Substance, or a condition involving or resulting
from same, has come to be located in, on, under or about the Premises, other
than as previously consented to by Lessor, Lessee shall immediately give
written notice of such fact to Lessor. Lessee shall also immediately give
Lessor a copy of any statement, report, notice, registration, application,
permit, business plan, license, claim, action or proceeding given to, or
received from, any governmental authority or private party, or persons
entering or occupying the Premises, concerning the presence, spill, release,
discharge of, or exposure to, any Hazardous Substance or contamination in,
on, or about the Premises, including but not limited to all such documents as
may be involved in any Reportable Uses involving the Premises.

        (c) INDEMNIFICATION. Lessee shall indemnify, protect, defend and hold
Lessor, its agents, employees, lenders and ground lessor, if any, and the
Premises, harmless from and against any and all loss of rents and/or damages,
liabilities, judgments, costs, claims, liens, expenses, penalties, permits and
attorney's and consultant's fees arising out of or involving any Hazardous
Substance or storage tank brought onto the Premises by or for Lessee or under
Lessee's control. Lessee's obligations under this Paragraph 6 shall include, but
not be limited to, the effects of any contamination or injury to person,
property or the environment created or suffered by Lessee, and the cost of
investigation (including consultant's and attorney's fees and testing), removal,
remediation, restoration and/or abatement thereof, or of any contamination
therein involved, and shall survive the expiration or earlier termination of
this Lease. No termination, cancellation or release agreement entered into by
Lessor and Lessee shall release Lessee from its obligations under this Lease
with respect to Hazardous Substances or storage tanks, unless specifically so
agreed by Lessor in writing at the time of such agreement.

   6.3 LESSEE'S COMPLIANCE WITH LAW. Except as otherwise provided in this
Lease, Lessee, shall, at Lessee's sole cost and expense, fully, diligently
and in a timely manner, comply with all "APPLICABLE LAW," which term is used
in this Lease to include all laws, rules, regulations, ordinances,
directives, covenants, easements and restrictions of record, permits, the
requirements of any applicable fire insurance underwriter or rating bureau,
relating in any manner to the Premises (including but not limited to matters
pertaining to (i) industrial hygiene, (ii) environmental conditions on, in,
under or about the Premises, including soil and groundwater conditions, and
(iii) the use, generation, manufacture, production, installation,
maintenance, removal, transportation, storage, spill or release of any
Hazardous Substance or storage tank), now in effect or which may hereafter
come into effect, and whether or not reflecting a change in policy from any
previously existing policy. Lessee shall, within five (5) days after receipt
of Lessor's written request, provide Lessor with copies of all documents and
information, including, but not limited to, permits, registrations,
manifests, applications, reports and certificates, evidencing Lessee's
compliance with any Applicable Law specified by Lessor, and shall immediately
upon receipt, notify Lessor in writing (with copies of any documents
involved) of any threatened or actual claim, notice, citation, warning,
complaint or report pertaining to or involving failure by Lessee or the
Premises to comply with any Applicable Law.

   6.4 INSPECTION; COMPLIANCE. Lessor and Lessor's Lender(s) (as defined in
Paragraph 8.3(a)) shall have the right to enter the Premises at any time, in
the case of an emergency, and otherwise at reasonable times, for the purpose
of inspecting the condition of the Premises and for verifying compliance by
Lessee with this Lease and all Applicable Laws (as defined in Paragraph 6.3),
and to employ experts and/or consultants in connection therewith and/or to
advise Lessor with respect to Lessee's activities, including but not limited
to the installation, operation, use, monitoring, maintenance, or removal of
any Hazardous Substance or storage tank on or from the Premises. The costs
and expenses of any such inspections shall be paid by the party requesting
same, unless a Default or Breach of this Lease, violation of Applicable Law,
or a contamination, caused or materially contributed to by Lessee is found to
exist or be imminent, or unless the inspection is requested or ordered by a
governmental authority as the result of any such existing or imminent
violation or contamination caused or materially contributed to by Lessee. In
any such case, Lessee shall upon request reimburse Lessor or Lessor's Lender,
as the case may be, for the costs and expenses of such inspections.

7. MAINTENANCE; REPAIRS, UTILITY INSTALLATIONS; TRADE FIXTURES AND
   ALTERATIONS.

   7.1 LESSEE'S OBLIGATIONS.

       (a) Subject to the provisions of Paragraphs 2.2 (Lessor's warranty as to
condition), 2.3 (Lessor's warranty as to compliance with covenants, etc), 7.2
(Lessor's obligations to repair), 9 (damage and destruction), and 14
(condemnation), Lessee shall, at Lessee's sole cost and expense and at all
times, keep the Premises and every part thereof in good order, condition and
repair, structural and non-structural (whether or not such portion of the
Premises requiring repair, or the means of repairing the same, are reasonably or
readily accessible to Lessee, and whether or not the need for such repairs
occurs

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as a result of Lessee's use, any prior use, the elements or the age of such
portion of the Premises), including, without limiting the generality of the
foregoing, all equipment or facilities serving the Premises, such as
plumbing, heating, air conditioning, ventilating, electrical, lighting
facilities, boilers, fired or unfired pressure vessels, fire sprinkler and/or
standpipe and hose or other automatic fire extinguishing system, including
fire alarm and/or smoke detection systems and equipment, fire hydrants,
fixtures, walls (interior and exterior), foundations, ceilings, roofs,
floors, windows, doors, plate glass, skylights, landscaping, driveways,
parking lots, fences, retaining walls, signs, sidewalks and parkways located
in, on, about, or adjacent to the Premises. Lessee shall not cause or permit
any Hazardous Substance to be spilled or released in, on, under or about the
Premises (including through the plumbing or sanitary sewer system) and shall
promptly, at Lessee's expense, take all investigatory and/or remedial action
reasonably recommended, whether or not formally ordered or required, for the
cleanup of any contamination of, and for the maintenance, security and/or
monitoring of, the Premises, the elements surrounding same, or neighboring
properties, that was caused or materially contributed to by Lessee, or
pertaining to or involving any Hazardous Substance and/or storage tank
brought onto the Premises by or for Lessee or under its control. Lessee, in
keeping the Premises in good order, condition and repair, shall exercise and
perform good maintenance practices. Lessee's obligations shall include
restorations, replacements or renewals when necessary to keep the Premises
and all improvements thereon or a part thereof in good order, condition and
state of repair.

       (b) Except to the extent Lessor maintains such contracts and Lessee
reimburses pursuant to Paragraph 52 Lessee shall, at Lessee's sole cost and
expense, procure and maintain contracts, with copies to Lessor, in customary
form and substance for, and with contractors specializing and experienced in,
the inspection, maintenance and service of the following equipment and
improvements, if any, located on the Premises: (i) heating, air conditioning
and ventilation equipment, (ii) boiler, fired or unfired pressure vessels,
(iii) fire sprinkler and/or standpipe and hose or other automatic fire
extinguishing systems, including fire alarm and/or smoke detection, (iv)
landscaping and irrigation systems, (v) roof covering and drain maintenance
and (vi) asphalt and parking lot maintenance.

   7.2 LESSOR'S OBLIGATIONS. Except for Lessor's obligations in Paragraph 52
and the warranties and agreements of Lessor contained in Paragraph 2.2
(relating to condition of the Premises), 2.3 (relating to compliance with
covenants, restrictions and building code), 9 (relating to destruction of the
Premises) and 14 (relating to condemnation of the Premises), it is intended
by the Parties hereto that Lessor have no obligation, in any manner
whatsoever, to repair and maintain the Premises, the improvements located
thereon, or the equipment therein, whether structural or non structural, all
of which obligations are intended to be that of the Lessee under Paragraph
7.1 hereof. It is the intention of the Parties that the terms of this Lease
govern the respective obligations of the Parties as to maintenance and repair
of the Premises. Lessee and Lessor expressly waive the benefit of any statute
now or hereafter in effect to the extent it is inconsistent with the terms of
this Lease with respect to, or which affords Lessee the right to make repairs
at the expense of Lessor or to terminate this Lease by reason of, any needed
repairs.

    7.3 UTILITY INSTALLATIONS; TRADE FIXTURES; ALTERATIONS.

       (a) DEFINITIONS; CONSENT REQUIRED. The term "UTILITY INSTALLATIONS" is
used in this Lease to refer to all carpeting, window coverings, air lines, power
panels, electrical distribution, fire protection systems, lighting fixtures,
heating, ventilating, and air conditioning equipment, plumbing, and fencing in,
on or about the Premises. The term "TRADE FIXTURES" shall mean Lessee's
machinery and equipment that can be removed without doing material damage to the
Premises. The term "ALTERATIONS" shall mean any modification of the improvements
on the Premises from that which are provided by Lessor under the terms of this
Lease, other than Utility Installations or Trade Fixtures, whether by addition
or deletion. "LESSEE OWNED ALTERATIONS AND/OR UTILITY INSTALLATIONS" are defined
as Alterations and/or Utility Installations made by Lessee that are not yet
owned by Lessor as defined in Paragraph 7.4(a). Lessee shall not make any
Alterations or Utility Installations in, on, under or about the Premises without
Lessor's prior written consent. Lessee may, however, make non-structural Utility
Installations to the Interior of the Premises (excluding the roof), as long as
they are not visible from the outside, do not involve puncturing, relocating or
removing the roof or any existing walls, and the cumulative cost thereof during
the term of this Lease as extended does not exceed $25,000.

        (b) CONSENT. Any Alterations or Utility Installations that Lessee shall
desire to make and which require the consent of the Lessor shall be presented to
Lessor in written form with proposed detailed plans. All consents given by
Lessor, whether by virtue of Paragraph 7.3(a) or by subsequent specific consent,
shall be deemed conditioned upon: (i) Lessee's acquiring all applicable permits
required by governmental authorities, (ii) the furnishing of copies of such
permits together with a copy of the plans and specifications for the Alteration
or Utility Installation to Lessor prior to commencement of the work thereon, and
(iii) the compliance by Lessee with all conditions of said permits in a prompt
and expeditious manner. Any Alterations or Utility Installations by Lessee
during the term of this Lease shall be done in a good and workmanlike manner,
with good and sufficient materials, and in compliance with all Applicable Law.
Lessee shall promptly upon completion thereof furnish Lessor with as-built plans
and specifications therefor. Lessor may (but without obligation to do so)
condition its consent to any requested Alteration or Utility Installation that
costs $10,000 or more upon Lessee's providing Lessor with a lien and completion
bond in an amount equal to one and one-half times the estimated cost of such
Alteration or Utility Installation and/or upon Lessee's posting an additional
Security Deposit with Lessor under Paragraph 36 hereof.

       (c) INDEMNIFICATION. Lessee shall pay, when due, all claims for labor
or materials furnished or alleged to have been furnished to or for Lessee at
or for use on the Premises, which claims are or may be secured by any
mechanics' or materialmen's lien against the Premises or any interest
therein. Lessee shall give Lessor not less than ten (10) days' notice prior
to the commencement of any work in, on or about the Premises, and Lessor
shall have the right to post notices of non-responsibility in or on the
Premises as provided by law. If Lessee shall, in good faith, contest the
validity of any such lien, claim or demand, then Lessee shall, at its sole
expense defend and protect itself, Lessor and the Premises against the same
and shall pay and satisfy any such adverse judgment that may be rendered
thereon before the enforcement thereof against the Lessor or the Premises. If
Lessor shall require, Lessee shall furnish to Lessor a surety bond
satisfactory to Lessor in an amount equal to one and one-half times the
amount of such contested lien claim or demand, indemnifying Lessor against
liability for the same, as required by law for the holding of the Premises
free from the effect of such lien or claim. In addition, Lessor may require
Lessee to pay Lessor's attorney's fees and costs in participating in such
action if Lessor shall decide it is to its best interest to do so.

   7.4 OWNERSHIP; REMOVAL; SURRENDER; AND RESTORATION.

       (a) OWNERSHIP. Subject to Lessor's right to require their removal or
become the owner thereof as hereinafter provided in this Paragraph 7.4, all
Alterations and Utility Additions made to the Premises by Lessee shall be the
property of and owned by Lessee, but considered a part of the Premises. Lessor
may, at any time and at its option, elect in writing to Lessee to be the owner
of all or any specified part of the Lessee Owned Alterations, and Utility
Installations. Unless otherwise instructed per subparagraph 7.4(b) hereof, all
Lessee Owned Alterations and Utility Installations shall, at the expiration or
earlier termination of this Lease, become the property of Lessor and remain upon
and be surrendered by Lessee with the Premises.

       (b) REMOVAL. Unless otherwise agreed in writing, Lessor may require that
any or all Lessee Owned Alterations or Utility Installations be removed by the
expiration or earlier termination of this Lease, notwithstanding their
installation may have been consented to by Lessor. Lessor may require the
removal at any time of all or any part of any Lessee Owned Alterations or
Utility Installations made without the required consent of Lessor.

       (c) SURRENDER/RESTORATION. Lessee shall surrender the Premises by the end
of the last day of the Lease term or any earlier termination date, with all of
the improvements, parts and surfaces thereof clean and free of debris and in
good operating order, condition and state of repair, ordinary wear and tear
excepted. "ORDINARY WEAR AND TEAR" shall not include any damage or deterioration
that would have been prevented by good maintenance practice or by Lessee
performing all of its obligations under this Lease. Except as otherwise agreed
or specified in writing by Lessor, the Premises, as surrendered, shall include
the Utility Installations. The obligation of Lessee shall include the repair of
any damage occasioned by the installation, maintenance or removal of Lessee's
Trade Fixtures, furnishings, equipment, and Alterations and/or Utility
Installations, as well as the removal of any storage tank installed by or for
Lessee, and the removal, replacement, or remediation of any soil, material or
ground water contaminated by Lessee, all as may then be required by Applicable
Law and/or good practice. Lessee's Trade Fixtures shall remain the property of
Lessee and shall be removed by Lessee subject to its obligation to repair and
restore the Premises per this Lease.

8. INSURANCE; INDEMNITY.

   8.1 PAYMENT FOR INSURANCE. Regardless of whether the Lessor or Lessee is the
Insuring Party, Lessee shall pay for all insurance required under this Paragraph
8 except to the extent of the cost attributable to liability insurance carried
by Lessor in excess $1,000,000 per occurrence. Premiums for policy periods
commencing prior to or extending beyond the Lease term shall be prorated to
correspond to the Lease term. Payment shall be made by Lessee to Lessor within
ten (10) days following receipt of an invoice for any amount due.

   8.2 LIABILITY INSURANCE.

       (a) CARRIED BY LESSEE. Lessee shall obtain and keep in force during the
term of this Lease a Commercial General Liability policy of insurance protecting
Lessee and Lessor (as an additional insured) against claims for bodily injury,
personal injury and property damage based upon, involving or arising out of the
ownership, use, occupancy or maintenance of the Premises and all areas
appurtenant thereto. Such insurance shall be on an occurrence basis providing
single limit coverage in an amount not less than $1,000,000 per occurrence with
an "Additional Insured-Managers or Lessors of Premises" Endorsement and contain
the "Amendment of the Pollution Exclusion" for damage caused by heat, smoke or
fumes from a hostile fire. The policy shall not contain any intra-insured
exclusions as between insured persons or organizations, but shall include
coverage for liability assumed under this Lease as an "insured contract" for the
performance of Lessee's indemnity obligations under this Lease. The limits of
said insurance required by this Lease or as carried by Lessee shall not,
however, limit the liability of Lessee nor relieve Lessee of any obligation
hereunder. All insurance to be carried by Lessee shall be primary to and not
contributory with any similar insurance carried by Lessor, whose insurance shall
be considered excess insurance only.

       (b) CARRIED BY LESSOR. In the event Lessor is the Insuring Party,
Lessor shall also maintain liability insurance described in Paragraph 8.2(a),
above, in addition to, and not in lieu of, the Insurance required to be
maintained by Lessee. Lessee shall not be named as an additional insured
therein.

   8.3 PROPERTY INSURANCE--BUILDING, IMPROVEMENTS AND RENTAL VALUE.

       (a) BUILDING AND IMPROVEMENTS. The Insuring Party shall obtain and keep
in force during the term of this Lease a policy or policies in the name of
Lessor, with loss payable to Lessor and to the holders of any mortgages, deeds
of trust or ground leases on the Premises ("LENDER(S)"), insuring loss

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or damage to the Premises. The amount of such insurance shall be equal to the
full replacement cost of the Premises, as the same shall exist from time to
time, or the amount required by Lenders, but in no event more than the
commercially reasonable and available insurable value thereof if, by reason
of the unique nature or age of the improvements involved, such latter amount
is less than full replacement cost. If Lessor is the Insuring Party, however,
Lessee Owned Alterations and Utility Installations shall be insured by Lessee
under Paragraph 8.4 rather than by Lessor. If the coverage is available and
commercially appropriate, such policy or policies shall insure against all
risks of direct physical loss or damage (except the perils of flood and/or
earthquake unless required by a Lender), including coverage for any
additional costs resulting from debris removal and reasonable amounts of
coverage for the enforcement of any ordinance or law regulating the
reconstruction or replacement of any undamaged sections of the Premises
required to be demolished or removed by reason of the enforcement of any
building, zoning, safety or land use laws as the result of a covered cause of
loss. Said policy or policies shall also contain an agreed valuation
provision in lieu of any coinsurance clause, waiver of subrogation, and
inflation guard protection causing an increase in the annual property
insurance coverage amount by a factor of not less than the adjusted U.S.
Department of Labor Consumer Price Index for All Urban Consumers for the city
nearest to where the Premises are located. If such insurance coverage has a
deductible clause, the deductible amount shall not exceed $1,000 per
occurrence, and Lessee shall be liable for such deductible amount in the
event of an Insured Loss, as defined in Paragraph 9.1(c).

       (b) RENTAL VALUE. The Insuring Party shall, in addition, obtain and keep
in force during the term of this Lease a policy or policies in the name of
Lessor, with loss payable to Lessor and Lender(s), insuring the loss of the full
rental and other charges payable by Lessee to Lessor under this Lease for one
(1) year (including all real estate taxes, insurance costs, and any scheduled
rental increases). Said insurance shall provide that in the event the Lease is
terminated by reason of an insured loss, the period of indemnity for such
coverage shall be extended beyond the date of the completion of repairs or
replacement of the Premises, to provide for one full year's loss of rental
revenues from the date of any such loss. Said insurance shall contain an agreed
valuation provision in lieu of any coinsurance clause, and the amount of
coverage shall be adjusted annually to reflect the projected rental income,
property taxes, insurance premium costs and other expenses, if any, otherwise
payable by Lessee, for the next twelve (12) month period. Lessee shall be liable
for any deductible amount in the event of such loss.

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

       (d) TENANT'S IMPROVEMENTS. If the Lessor is the Insuring Party, the
Lessor shall not be required to insure Lessee Owned Alterations and Utility
Installations unless the item in question has become the property of Lessor
under the terms of this Lease. If Lessee is the Insuring Party, the policy
carried by Lessee under this Paragraph 8.3 shall insure Lessee Owned Alterations
and Utility Installations.

   8.4 LESSEE'S PROPERTY INSURANCE. Subject to the requirements of Paragraph
8.5, Lessee at its cost shall either by separate policy or, at Lessor's option,
by endorsement to a policy already carried, maintain insurance coverage on all
of Lessee's personal property, Lessee Owned Alterations and Utility
Installations in, on, or about the Premises similar in coverage to that carried
by the Insuring Party under Paragraph 8.3. Such insurance shall be full
replacement cost coverage with a deductible of not to exceed $1,000 per
occurrence. The proceeds from any such insurance shall be used by Lessee for the
replacement of personal property or the restoration of Lessee Owned Alterations
and Utility Installations. Lessee shall be the Insuring Party with respect to
the insurance required by this Paragraph 8.4 and shall provide Lessor with
written evidence that such insurance is in force.

   8.5 INSURANCE POLICIES. Insurance required hereunder shall be in companies
duly licensed to transact business in the state where the Premises are located,
and maintaining during the policy term a "General Policyholders Rating" of at
least B+, V, or such other rating as may be required by a Lender having a lien
on the Premises, as set forth in the most current issue of "Best's Insurance
Guide." Lessee shall not do or permit to be done anything which shall invalidate
the insurance policies referred to in this Paragraph 8. If Lessee is the
Insuring Party, Lessee shall cause to be delivered to Lessor certified copies of
policies of such insurance or certificates evidencing the existence and amounts
of such insurance with the insureds and loss payable clauses as required by this
Lease. No such policy shall be cancellable or subject to modification except
after thirty (30) days prior written notice to Lessor. Lessee shall at least
thirty (30) days prior to the expiration of such policies, furnish Lessor with
evidence of renewals or "insurance binders" evidencing renewal thereof, or
Lessor may order such insurance and charge the cost thereof to Lessee, which
amount shall be payable by Lessee to Lessor upon demand. If the Insuring Party
shall fail to procure and maintain the insurance required to be carried by the
Insuring Party under this Paragraph 8, the other Party may, but shall not be
required to, procure and maintain the same, but at Lessee's expense.

   8.6 WAIVER OF SUBROGATION. Without affecting any other rights or remedies,
Lessee and Lessor ("WAIVING PARTY") each hereby release and relieve the other,
and waive their entire right to recover damages (whether in contract or in tort)
against the other, for loss of or damage to the Waiving Party's property arising
out of or incident to the perils required to be insured against under Paragraph
8. The effect of such releases and waivers of the right to recover damages shall
not be limited by the amount of insurance carried or required, or by any
deductibles applicable thereto.

   8.7 INDEMNITY. Except for Lessor's negligence and/or breach of express
warranties, Lessee shall indemnify, protect, defend and hold harmless the
Premises, Lessor and its agents, Lessor's master or ground lessor, partners
and Lenders, from and against any and all claims bought by parties other than
Lessee, loss of rents and/or damages, costs, liens, judgments, penalties,
permits, attorney's and consultant's fees, expenses and/or liabilities
arising out of, involving, or in dealing with, the occupancy of the Premises
by Lessee, the conduct of Lessee's business, any act, omission or neglect of
Lessee, its agents, contractors, employees or invitees, and out of any
Default or Breach of Lessee in the performance in a timely manner of any
obligation on Lessee's part to be performed under this Lease. The foregoing
shall include, but not be limited to, the defense or pursuit of any claim or
any action or proceeding involved therein, and whether or not (in the case of
claims made against Lessor) litigated and/or reduced to judgment, and whether
well founded or not. In case any action or proceeding brought by parties
other than Lessee be brought against Lessor by reason of any of the foregoing
matters, Lessee upon notice from Lessor shall defend the same at Lessee's
expense by counsel reasonably satisfactory to Lessor and Lessor shall
cooperate with Lessee in such defense. Lessor need not have first paid any
such claim in order to be so indemnified.

   8.8 EXEMPTION OF LESSOR FROM LIABILITY. Except to the extent caused solely
by Lessor and only to the extent paid by insurance carried by Lessor, Lessor
shall not be liable for injury or damage to the person or goods, wares,
merchandise or other property of Lessee, Lessee's employees, contractors,
invitees, customers, or any other person in or about the Premises, whether
such damage or injury is caused by or results from fire, steam, electricity,
gas, water or rain, or from the breakage, leakage, obstruction or other
defects of pipes, fire sprinklers, wires, appliances, plumbing, air
conditioning or lighting fixtures, or from any other cause, whether the said
injury or damage results from conditions arising upon the Premises or upon
other portions of the building of which the Premises are a part, or from
other sources or places, and regardless of whether the cause of such damage
or injury or the means of repairing the same is accessible or not. Lessor
shall not be liable for any damages arising from any act or neglect of any
other tenant of Lessor. Notwithstanding Lessor's negligence or breach of this
Lease, Lessor shall under no circumstances be liable for injury to Lessee's
business or for any loss of income or profit therefrom.

9. DAMAGE OR DESTRUCTION.

    9.1 DEFINITIONS.

       (a) "PREMISES PARTIAL DAMAGE" shall mean damage or destruction to the
Improvements on the Premises, other than Lessee Owned Alterations and Utility
Installations, the repair cost of which damage or destruction is less than 50%
of the then Replacement Cost of the Premises immediately prior to such damage or
destruction, excluding from such calculation the value of the land and Lessee
Owned Alterations and Utility Installations.

       (b) "PREMISES TOTAL DESTRUCTION" shall mean damage or destruction to the
Premises, other than Lessee Owned Alterations and Utility Installations the
repair cost of which damage or destruction is 50% or more of the then
Replacement Cost of the Premises immediately prior to such damage or
destruction, excluding from such calculation the value of the land and Lessee
Owned Alterations and Utility Installations.

       (c) "INSURED LOSS" shall mean damage or destruction to improvements on
the Premises, other than Lessee Owned Alterations and Utility Installations,
which was caused by an event required to be covered by the insurance described
in Paragraph 8.3(a), irrespective of any deductible amounts or coverage limits
involved.

       (d) "REPLACEMENT COST" shall mean the cost to repair or rebuild the
improvements owned by Lessor at the time of the occurrence to their condition
existing immediately prior thereto, including demolition, debris removal and
upgrading required by the operation of applicable building codes, ordinances
or laws, and without deduction for depreciation.

       (e) "HAZARDOUS SUBSTANCE CONDITION" shall mean the occurrence or
discovery of a condition involving the presence of, or a contamination by, a
Hazardous Substance as defined in Paragraph 6.2(a), in, on, or under the
Premises.

   9.2 PARTIAL DAMAGE--INSURED LOSS. If a Premises Partial Damage that is an
Insured Loss occurs, then Lessor shall, at Lessor's expense, repair such
damage (but not Lessee's Trade Fixtures or Lessee Owned Alterations and
Utility Installations) as soon as reasonably possible and this Lease shall
continue in full force and effect; provided, however, that Lessee shall, at
Lessor's election, make the repair of any damage or destruction the total
cost to repair of which is $10,000 or less, and, in such event, Lessor shall
make the insurance proceeds available to Lessee on a reasonable basis for
that purpose. Notwithstanding the foregoing, if the required insurance was
not in force or the insurance proceeds are not sufficient to effect such
repair, the Insuring Party shall promptly contribute the shortage in
proceeds (except as to the deductible which is Lessee's responsibility) as
and when required to complete said repairs. In the event, however, the
shortage in proceeds was due to the fact that, by reason of the unique nature
of the improvements, full replacement cost insurance coverage was not
commercially reasonable and available, Lessor shall have no obligation to pay
for the shortage in insurance proceeds or to fully restore the unique aspects
of the Premises unless Lessee provides Lessor with the funds to cover same,
or adequate assurance thereof, within ten (10) days following receipt of
written notice of such shortage and request therefor. If Lessor receives said
funds or adequate assurance thereof within said ten (10) day period, the
party responsible for making the repairs shall complete them as soon as
reasonably possible and this Lease shall remain in full force and effect. If
Lessor does not receive such funds or assurance within said period, Lessor
may nevertheless elect by written notice to Lessee within ten (10) days
thereafter to make such restoration and repair as is commercially reasonable
with Lessor paying any shortage in proceeds, in which case this Lease shall
remain in full force and effect. If in such case Lessor does not so elect,
then this Lease shall terminate sixty (60) days following the occurrence of
the damage or destruction. Unless otherwise agreed, Lessee shall in no event
have any right to reimbursement from Lessor for any funds contributed by
Lessee to repair any such damage or destruction. Premises Partial Damage due
to flood or earthquake shall be subject to Paragraph 9.3 rather than
Paragraph 9.2, notwithstanding that there may be some insurance coverage, but
the net proceeds of any such insurance shall be made available for the
repairs if made by either Party.

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  9.3 PARTIAL DAMAGE--UNINSURED LOSS. If a Premises Partial Damage that is not
an Insured Loss occurs, unless caused by a negligent or willful act of Lessee
(in which event Lessee shall make the repairs at Lessee's expense and this Lease
shall continue in full force and effect, but subject to Lessor's rights under
Paragraph 13), Lessor may at Lessor's option, either: (i) repair such damage as
soon as reasonably possible at Lessor's expense, in which event this Lease shall
continue in full force and effect, or (ii) give written notice to Lessee within
thirty (30) days after receipt by Lessor of knowledge of the occurrence of such
damage of Lessor's desire to terminate this Lease as of the date sixty (60) days
following the giving of such notice. In the event Lessor elects to give such
notice of Lessor's intention to terminate this Lease, Lessee shall have the
right within ten (10) days after the receipt of such notice to give written
notice to Lessor of Lessee's commitment to pay for the repair of such damage
totally at Lessee's expense and without reimbursement from Lessor. Lessee shall
provide Lessor with the required funds or satisfactory assurance thereof within
thirty (30) days following Lessee's said commitment. In such event this Lease
shall continue in full force and effect, and Lessor shall proceed to make such
repairs as soon as reasonably possible and the required funds are available. If
Lessee does not give such notice and provide the funds or assurance thereof
within the times specified above, this Lease shall terminate as of the date
specified in Lessor's notice of termination.

   9.4 TOTAL DESTRUCTION. Notwithstanding any other provision hereof, if a
Premises Total Destruction occurs (including any destruction required by any
authorized public authority), this Lease shall terminate sixty (60) days
following the date of such Premises Total Destruction, whether or not the
damage or destruction is an Insured Loss or was caused by a negligent or
willful act of Lessee. In the event, however, that the damage or destruction was
caused by Lessee, Lessor shall have the right to recover Lessor's damages from
Lessee except as released and waived in Paragraph 8.6.

   9.5 DAMAGE NEAR END OF TERM. If at any time during the last six (6) months of
the term of this Lease there is damage for which the cost to repair exceeds one
(1) month's Base Rent, whether or not an Insured Loss, Lessor may, at Lessor's
option, terminate this Lease effective sixty (60) days following the date of
occurrence of such damage by giving written notice to Lessee of Lessor's
election to do so within thirty (30) days after the date of occurrence of such
damage. Provided, however, if Lessee at that time has an exercisable option to
extend this Lease or to purchase the Premises, then Lessee may preserve this
Lease by, within twenty (20) days following the occurrence of the damage, or
before the expiration of the time provided in such option for its exercise,
whichever is earlier ("EXERCISE PERIOD"), (i) exercising such option and (ii)
providing Lessor with any shortage in insurance proceeds (or adequate assurance
thereof) needed to make the repairs. If Lessee duly exercises such option during
said Exercise Period and provides Lessor with funds (or adequate assurance
thereof) to cover any shortage in insurance proceeds, Lessor shall, at Lessor's
expense repair such damage as soon as reasonably possible and this Lease shall
continue in full force and effect. If Lessee fails to exercise such option and
provide such funds or assurance during said Exercise Period, then Lessor may at
Lessor's option terminate this Lease as of the expiration of said sixty (60) day
period following the occurrence of such damage by giving written notice to
Lessee of Lessor's election to do so within ten (10) days after the expiration
of the Exercise Period, notwithstanding any term or provision in the grant of
option to the contrary.

   9.6 ABATEMENT OF RENT; LESSEE'S REMEDIES.

       (a) In the event of damage described in Paragraph 9.2 (Partial Damage--
Insured), whether or not Lessor or Lessee repairs or restores the Premises, the
Base Rent, Real Property Taxes, insurance premiums, and other charges, if any,
payable by Lessee hereunder for the period during which such damage, its repair
or the restoration continues (not to exceed the period for which rental value
insurance is required under Paragraph 8.3(b)), shall be abated in proportion to
the degree to which Lessee's use of the Premises is impaired. Except for
abatement of Base Rent, Real Property Taxes, insurance premiums, and other
charges, if any, as aforesaid, all other obligations of Lessee hereunder shall
be performed by Lessee, and Lessee shall have no claim against Lessor for any
damage suffered by reason of any such repair or restoration.

       (b) If Lessor shall be obligated to repair or restore the Premises under
the provisions of this Paragraph 9 and shall not commence, in a substantial and
meaningful way, the repair or restoration of the Premises within ninety (90)
days after such obligation shall accrue, Lessee may, at any time prior to the
commencement of such repair or restoration, give written notice to Lessor and to
any Lenders of which Lessee has actual notice of Lessee's election to terminate
this Lease on a date not less than sixty (60) days following the giving of such
notice. If Lessee gives such notice to Lessor and such Lenders and such repair
or restoration is not commenced within thirty (30) days after receipt of such
notice, this Lease shall terminate as of the date specified in said notice. If
Lessor or a Lender commences the repair or restoration of the Premises within
thirty (30) days after receipt of such notice, this Lessee shall continue in
full force and effect. "COMMENCE" as used in this Paragraph shall mean either
the unconditional authorization of the preparation of the required plans, or the
beginning of the actual work on the Premises, whichever first occurs.

   9.7 HAZARDOUS SUBSTANCE CONDITIONS. If a Hazardous Substance Condition
occurs, unless Lessee is legally responsible therefor (in which case Lessee
shall make the investigation and remediation thereof required by Applicable
Law and this Lease shall continue in full force and effect, but subject to
Lessor's rights under Paragraph 13), Lessor may at Lessor's option either (i)
investigate and remediate such Hazardous Substance Condition, if required, as
soon as reasonably possible at Lessor's expense, in which event this Lease
shall continue in full force and effect, or (ii) if the estimated cost to
investigate and remediate such condition exceeds twelve (12) times the then
monthly Base Rent or $100,000, whichever is greater, give written notice to
Lessee within thirty (30) days after receipt by Lessor of knowledge of the
occurrence of such Hazardous Substance Condition of Lessor's desire to
terminate this Lease as of the date sixty (60) days following the giving of
such notice. In the event Lessor elects to give such notice of Lessor's
intention to terminate this Lease, Lessee shall have the right within ten
(10) days after the receipt of such notice to give written notice to Lessor
of Lessee's commitment to pay for the investigation and remediation of such
Hazardous Substance Condition totally at Lessee's expense and without
reimbursement from Lessor except to the extent of an amount equal to twelve
(12) times the then monthly Base Rent or $100,000, whichever is greater.
Lessee shall provide Lessor with the funds required of Lessee or satisfactory
assurance thereof within thirty (30) days following Lessee's said commitment,
in such event this Lease shall continue in full force and effect, and Lessor
shall proceed to make such investigation and remediation as soon as
reasonably possible and the required funds are available. If Lessee does not
give such notice and provide the required funds or assurance thereof within
the times specified above, this Lease shall terminate as of the date
specified in Lessor's notice of termination. If a Hazardous Substance
Condition occurs for which Lessee is not legally responsible, there shall be
abatement of Lessee's obligations under this Lease to the same extent as
provided in Paragraph 9.6(a) for a period of not to exceed twelve months.

   9.8 TERMINATION--ADVANCE PAYMENTS. Upon termination of this Lease pursuant
to this Paragraph 9, an equitable adjustment shall be made concerning advance
Base Rent and any other advance payments made by Lessee to Lessor. Lessor shall,
in addition, return to Lessee so much of Lessee's Security Deposit as has not
been, or is not then required to be, used by Lessor under the terms of this
Lease.

   9.9 WAIVE STATUTES. Lessor and Lessee agree that the terms of this Lease
shall govern the effect of any damage to or destruction of the Premises with
respect to the termination of this Lease and hereby waive the provisions of any
present or future statute to the extent inconsistent herewith.

10. REAL PROPERTY TAXES.

    10.1 (a) PAYMENT OF TAXES. Lessee shall pay the Real Property Taxes, as
defined in Paragraph 10.2, applicable to the Premises during the term of this
Lease. Subject to Paragraph 10.1(b), all such payments shall be made at least
ten (10) days prior to the delinquency date of the applicable installment.
Lessee shall promptly furnish Lessor with satisfactory evidence that such
taxes have been paid. If any such taxes to be paid by Lessee shall cover any
period of time prior to or after the expiration or earlier termination of the
term hereof, Lessee's share of such taxes shall be equitably prorated to
cover only the period of time within the tax fiscal year this Lease is in
effect, and Lessor shall reimburse Lessee for any overpayment after such
proration. If Lessee shall fail to pay any Real Property Taxes required by
this Lease to be paid by Lessee, Lessor shall have the right to pay the same,
and Lessee shall reimburse Lessor therefor upon demand.

        (b) ADVANCE PAYMENT. In order to insure payment when due and before
delinquency of any or all Real Property Taxes, Lessor reserves the right, at
Lessor's option, to estimate the current Real Property Taxes applicable to
the Premises, and to require such current year's Real Property Taxes to be
paid in advance to Lessor by Lessee, either: (i) in a lump sum amount equal
to the installment due, at least twenty (20) days prior to the applicable
delinquency date, or (ii) monthly in advance with the payment of the Base
Rent. If Lessor elects to require payment monthly in advance, the monthly
payment shall be that equal monthly amount which, over the number of months
remaining before the month in which the applicable tax installment would
become delinquent (and without interest thereon), would provide a fund large
enough to fully discharge before delinquency the estimated installment of
taxes to be paid. When the actual amount of the applicable tax bill is known,
the amount of such equal monthly advance payment shall be adjusted as
required to provide the fund needed to pay the applicable taxes before
delinquency. If the amounts paid to Lessor by Lessee under the provisions of
this Paragraph are insufficient to discharge the obligations of Lessee to pay
such Real Property Taxes as the same become due, Lessee shall pay to Lessor,
upon Lessor's demand, such additional sums as are necessary to pay such
obligations. All moneys paid to Lessor under this Paragraph may be
intermingled with other moneys of Lessor and shall not bear interest. In the
event of a Breach by Lessee in the performance of the obligations of Lessee
under this Lease, then any balance of funds paid to Lessor under the
provisions of this Paragraph may, subject to proration as provided in
Paragraph 10.1(a), at the option of Lessor, be treated as an additional
Security Deposit under Paragraph 5.

   10.2 DEFINITION OF "REAL PROPERTY TAXES." As used herein, the term "REAL
PROPERTY TAXES" shall include any form of real estate tax or assessment,
general, special, ordinary or extraordinary, and any license fee, commercial
rental tax, improvement bond or bonds, levy or tax (other than inheritance,
personal income or estate taxes) imposed upon the Premises by an authority
having the direct or indirect power to tax, including any city, state or
federal government, or any school, agricultural, sanitary, fire, street,
drainage or other improvement district thereof, levied against any legal or
equitable interest of Lessor in the Premises or in the real property of which
the Premises are a part, Lessor's right to rent or other income therefrom,
and/or Lessor's business of leasing the Premises. The term "REAL PROPERTY
TAXES" shall also include any tax, fee, levy, assessment or charge, or any
increase therein, imposed by reason of events occurring, or changes in
applicable law taking effect, during the term of this Lease, including but
not limited to a charge in the ownership of the Premises or in the
improvements thereon, the execution of this Lease, or any modification,
amendment or transfer thereof, and whether or not contemplated by the Parties.

   10.3 JOINT ASSESSMENT. If the Premises are not separately assessed, Lessee's
liability shall be an equitable proportion of the Real Property Taxes for all of
the land and improvements included within the tax parcel assessed, such
proportion to be determined by Lessor from the respective valuations assigned in
the assessor's work sheets or such other information as may be reasonably
available. Lessor's reasonable determination thereof, in good faith, shall be
conclusive.

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   10.4 PERSONAL PROPERTY TAXES. Lessee shall pay prior to delinquency all
taxes assessed against and levied upon Lessee Owned Alterations, Utility
Installations, Trade Fixtures, furnishings, equipment and all personal
property of Lessee contained in the Premises or elsewhere. When possible,
Lessee shall cause its Trade Fixtures, furnishings, equipment and all other
personal property to be assessed and billed separately from the real property
of Lessor. If any of Lessee's said personal property shall be assessed with
Lessor's real property, Lessee shall pay Lessor the taxes attributable to
Lessee within ten (10) days after receipt of a written statement setting
forth the taxes applicable to Lessee's property or, at Lessor's option, as
provided in Paragraph 10.1(b).

11. UTILITIES: Lessee shall pay for all water, gas, heat, light, power,
telephone, trash disposal and other utilities and services supplied to the
Premises, together with any taxes thereon. If any such services are not
separately metered to Lessee, Lessee shall pay a reasonable proportion, to be
determined by Lessor, of all charges jointly metered with other premises.

12. ASSIGNMENT AND SUBLETTING.

    12.1 LESSOR'S CONSENT REQUIRED.

        (a) Lessee shall not voluntarily or by operation of law assign,
transfer, mortgage or otherwise transfer or encumber (collectively,
"ASSIGNMENT") or sublet all or any part of Lessee's interest in this Lease or in
the Premises without Lessor's prior written consent given under and the subject
to the terms of Paragraph 36.

        (b) A change in the control of Lessee shall constitute an assignment
requiring Lessor's consent. The transfer, on a cumulative basis, of twenty-five
percent (25%) or more of the voting control of Lessee shall constitute a change
in control for this purpose.

        (c) The involvement of Lessee or its assets in any transaction, or
series of transactions (by way of merger, sale, acquisition, financing,
refinancing, transfer, leveraged buy-out or otherwise), whether or not a
formal assignment or hypothecation of this Lease or Lessee's assets occurs,
which results or will result in a reduction of the Net Worth of Lessee, as
hereinafter defined, by an amount equal to or greater than twenty-five
percent (25%) of such Net Worth of Lessee as it was represented to Lessor at
the time of the execution by Lessor of this Lease or at the time of the most
recent assignment to which Lessor has consented, or as it exists immediately
prior to said transaction or transactions constituting such reduction, at
whichever time said Net Worth of Lessee was or is greater, shall be
considered an assignment of this Lease by Lessee to which Lessor may
reasonably withhold its consent. "NET WORTH OF LESSEE" for purposes of this
Lease shall be the net worth of Lessee (excluding any guarantors) established
under generally accepted accounting principles consistently applied.

        (d) An assignment or subletting of Lessee's interest in this Lease
without Lessor's specific prior written consent shall, at Lessor's option, be a
Default curable after notice per Paragraph 13.1(c), or a noncurable Breach
without the necessity of any notice and grace period. If Lessor elects to treat
such unconsented to assignment or subletting as a noncurable Breach, Lessor
shall have the right to either: (i) terminate this Lease, or (ii) upon thirty
(30) days written notice ("Lessor's Notice"), increase the monthly Base Rent to
fair market rental value or one hundred ten percent (110%) of the Base Rent then
in effect, whichever is greater. Pending determination of the new fair market
rental value, if disputed by Lessee, Lessee shall pay the amount set forth in
Lessor's Notice, with any overpayment credited against the next installment(s)
of Base Rent coming due, and any underpayment for the period retroactively to
the effective date of the adjustment being due and payable immediately upon the
determination thereof. Further, in the event of such Breach and market value
adjustment, (i) the purchase price of any option to purchase the Premises held
by Lessee shall be subject to similar adjustment to the then fair market value
(without the Lease being considered an encumbrance or any deduction for
depreciation or obsolescence, and considering the Premises at its highest and
best use and in good condition), or one hundred ten percent (110%) of the price
previously in effect, whichever is greater, (ii) any index-oriented rental or
price adjustment formulas contained in this Lease shall be adjusted to require
that the base index be determined with reference to the index applicable to the
time of such adjustment, and (iii) any fixed rental adjustments scheduled during
the remainder of the Lease term shall be increased in the same ratio as the new
market rental bears to the Base Rent in effect immediately prior to the market
value adjustment.

    12.2 TERMS AND CONDITIONS APPLICABLE TO ASSIGNMENT AND SUBLETTING.

        (a) Regardless of Lessor's consent, any assignment or subletting
shall not: (i) be effective without the express written assumption by such
assignee or sublessee of the obligations of Lessee under this Lease, (ii)
release Lessee of any obligations hereunder, or (iii) alter the primary
liability of Lessee for the payment of Base Rent and other sums due Lessor
hereunder or for the performance of any other obligations to be performed by
Lessee under this Lease.

        (b) Lessor may accept any rent or performance of Lessor's obligations
from any person other than Lessee pending approval or disapproval of an
assignment. Neither a delay in the approval or disapproval of such assignment
nor the acceptance of any rent or performance shall constitute a waiver or
estoppel of Lessor's right to exercise its remedies for the Default or Breach by
Lessee of any of the terms, covenants or conditions of this Lease.

        (c) The consent of Lessor to any assignment or subletting shall not
constitute a consent to any subsequent assignment or subletting by Lessee
or to any subsequent or successive assignment or subletting by the sublessee.
However, Lessor may consent to subsequent sublettings and assignments of the
sublease or any amendments or modifications thereto without notifying Lessee or
anyone else liable on the Lease or sublease and without obtaining their consent,
and such action shall not relieve such persons from liability under this Lease
or sublease.

        (d) In the event of any Default or Breach of Lessee's obligations under
this Lease, Lessor may proceed directly against Lessee, any Guarantors or any
one else responsible for the performance of the Lessee's obligations under this
Lease, including the sublessee, without first exhausting Lessor's remedies
against any other person or entity responsible therefor to Lessor, or any
security held by Lessor or Lessee.

        (e) Each request for consent to an assignment or subletting shall be in
writing, accompanied by information relevant to Lessor's determination as to the
financial and operational responsibility and appropriateness of the proposed
assignee or sublessee, including but not limited to the intended use and/or
required modification of the Premises, if any, together with a non-refundable
deposit of $1,000 or ten percent (10%) of the current monthly Base Rent,
whichever is greater, as reasonable consideration for Lessor's considering and
processing the request for consent. Lessee agrees to provide Lessor with such
other or additional information and/or documentation as may be reasonably
requested by Lessor.

        (f) Any assignee of, or sublessee under, this Lease shall, by reason
of accepting such assignment or entering into such sublease, be deemed, for
the benefit of Lessor, to have assumed and agreed to conform and comply with
each and every term, covenant, condition and obligation herein to be observed
or performed by Lessee during the term of said assignment or sublease, other
than such obligations as are contrary to or inconsistent with provisions of
an assignment or sublease to which Lessor has specifically consented in
writing.

        (g) The occurrence of a transaction described in Paragraph 12.1(c) shall
give Lessor the right (but not the obligation) to require that the Security
Deposit be increased to an amount equal to six (6) times the then monthly Base
Rent, and Lessor may make the actual receipt by Lessor of the amount required to
establish such Security Deposit a condition to Lessor's consent to such
transaction.

   12.3 ADDITIONAL TERMS AND CONDITIONS APPLICABLE TO SUBLETTING. The following
terms and conditions shall apply to any subletting by Lessee of all or any part
of the Premises and shall be deemed included in all subleases under this Lease
whether or not expressly incorporated therein:

        (a) Lessee hereby assigns and transfers to Lessor all of Lessee's
interest in all rentals and income arising from any sublease of all or a portion
of the Premises heretofore or hereafter made by Lessee, and Lessor may collect
such rent and income and apply same toward of Lessee's obligations under this
Lease; provided, however, that until a Breach (as defined in Paragraph 13.1)
shall occur in the performance of Lessee's obligations under this Lease, Lessee
may, except as otherwise provided in this Lease, receive, collect and enjoy the
rents accruing under such sublease. Lessor shall not, by reason of this or any
other assignment of such sublease to Lessor, nor by reason of the collection of
the rents from a sublease, be deemed liable to the sublessee for any failure of
Lessee to perform and comply with any of Lessee's obligations to such sublessee
under such sublease. Lessee hereby irrevocably authorizes and directs any such
sublessee, upon receipt of a written notice from Lessor stating that a
Breach exists in the performance of Lessee's obligations under this Lease, to
pay to Lessor the rents and other charges due and to become due under the
sublease. Sublessee shall rely upon any such statement and request from
Lessor and shall pay such rents and other charges to Lessor without any
obligation or right to inquire as to whether such Breach exists and
notwithstanding any notice from or claim from Lessee to the contrary. Lessee
shall have no right or claim against said sublessee, or, until the Breach has
been cured, against Lessor, for any such rents and other charges so paid by said
sublessee to Lessor.

        (b) In the event of a Breach by Lessee in the performance of its
obligations under this Lease, at its option and without any obligation to do
so, may require any sublessee to attorn to Lessor, in which event Lessor
shall undertake the obligations of the sublessor under such sublease from the
time of the exercise of said option to the expiration of such sublease;
provided, however, Lessor shall not be liable for any prepaid rents or
security deposit paid by such sublessee to such sublessor or for any other
prior Defaults or Breaches of such sublessor under such sublease.

        (c) Any matter or thing requiring the consent of the sublessor under a
sublease shall also require the consent of Lessor herein.

        (d) No sublessee shall further assign or sublet all or any part of the
Premises without Lessor's prior written consent.

        (e) Lessor shall deliver a copy of any notice of Default or Breach by
Lessee to the sublessee, who shall have the right to cure the Default of Lessee
within the grace period, if any, specified in such notice. The sublessee shall
have a right of reimbursement and offset from and against Lessee for any such
Defaults cured by the sublessee.

13. DEFAULT; BREACH; REMEDIES.

    13.1 DEFAULT; BREACH. A "DEFAULT" is defined as a failure by the Lessee
to observe, comply with or perform any of the terms, covenants, conditions or
rules applicable to Lessee under this Lease. A "BREACH" is defined as the
occurrence of any one of more of the following Defaults, and, where a grace
period for cure after notice is specified herein, the failure by Lessee to
cure such Default prior to the expiration of the applicable grace period, and
shall entitle Lessor to pursue the remedies set forth in Paragraphs 13.2
and/or 13.3:

        (a) The vacating of the Premises without the intention to reoccupy
same, or the abandonment of the Premises.

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        (b) Except as expressly otherwise provided in this Lease, the failure by
Lessee to make any payment of Base Rent or any other monetary payment required
to be made by Lessee hereunder, whether to Lessor or to a third party, as and
when due, the failure by Lessee to provide Lessor with reasonable evidence of
insurance or surety bond required under this Lease, or the failure of Lessee to
fulfill any obligation under this Lease which endangers or threatens life or
property, where such failure continues for a period of three (3) days following
written notice thereof by or on behalf of Lessor to Lessee.

        (c) Except as expressly otherwise provided in this Lease, the failure by
Lessee to provide Lessor with reasonable written evidence (in duly executed
original form, if applicable) of (i) compliance with applicable law per
Paragraph 6.3, (ii) the inspection, maintenance and service contracts required
under Paragraph 7.1(b), (iii) the recission of an unauthorized assignment or
subletting per Paragraph 12.1(b), (iv) a Tenancy Statement per Paragraphs 16 or
37, (v) the subordination or non-subordination of this Lease per Paragraph 30,
(vi) the guaranty of the performance of Lessee's obligations under this Lease if
required under Paragraphs 1.11 and 37, (vii) the execution of any document
requested under Paragraph 42 (easements), or (viii) any other documentation or
information which Lessor may reasonably require of Lessee under the terms of
this Lease, where any such failure continues for a period of twenty (20) days
following written notice by or on behalf of Lessor to Lessee.

        (d) A Default by Lessee as to the terms, covenants, conditions or
provisions of this Lease, or of the rules adopted under Paragraph 40 hereof,
that are to be observed, complied with or performed by Lessee, other than those
described in subparagraphs (a), (b) or (c), above, where such Default continues
for a period of thirty (30) days after written notice thereof by or on behalf of
Lessor to Lessee; provided, however, that if the nature of Lessee's Default is
such that more than thirty (30) days are reasonably required for its cure, then
it shall not be deemed to be a Breach of this Lease by Lessee if Lessee
commences such cure within said thirty (30) day period and thereafter diligently
prosecutes such cure to completion.

        (e) The occurrence of any of the following events: (i) The making by
Lessee of any general arrangement or assignment for the benefit of creditors;
(ii) Lessee's becoming a "debtor" as defined in 11 U.S.C. Section 101 or any
successor statute thereto (unless, in the case of a petition filed against
Lessee, the same is dismissed within sixty (60) days); (iii) the appointment of
a trustee or receiver to take possession of substantially all of Lessee's assets
located at the Premises or of Lessee's Interest in this Lease, where possession
is not restored to Lessee within thirty (30) days; or (iv) the attachment,
execution or other judicial seizure of substantially all of Lessee's assets
located at the Premises or of Lessee's interest in this Lease, where such
seizure is not discharged within thirty (30) days; provided, however, in the
event that any provision of this subparagraph (e) is contrary to any applicable
law, such provision shall be of no force or effect, and not affect the validity
of the remaining provisions.

        (f) The discovery by Lessor that any financial statement given to Lessor
by Lessee or any Guarantor of Lessee's obligations hereunder was materially
false.

        (g) If the performance of Lessee's obligations under this Lease is
guaranteed: (i) the death of a guarantor, (ii) the termination of a guarantor's
liability with respect to this Lease other than in accordance with the terms of
such guaranty, (iii) a guarantor's becoming insolvent or the subject of a
bankruptcy filing, (iv) a guarantor's refusal to honor the guaranty, or (v) a
guarantor's breach of its guaranty obligation on an anticipatory breach basis,
and Lessee's failure, within sixty (60) days following written notice by or on
behalf of Lessor to Lessee of any such event, to provide Lessor with written
alternative assurance or security, which, when coupled with the then existing
resources of Lessee, equals or executes the combined financial resources of
Lessee and the guarantors that existed at the time of execution of this Lease.

   13.2 REMEDIES. If Lessee fails to perform any affirmative duty or obligation
of Lessee under this Lease, within twenty (20) days after written notice to
Lessee (or in case of an emergency, without notice), Lessor may at its option
(but without obligation to do so), perform such duty or obligation on Lessee's
behalf, including but not limited to the obtaining of reasonably required bonds,
insurance policies, or governmental licenses, permits or approvals. The costs
and expenses of any such performance by Lessor shall be due and payable by
Lessee to Lessor upon invoice therefor. If any check given to Lessor by Lessee
shall not be honored by the bank upon which it is drawn, Lessor, at its option,
may require all future payments to be made under this Lease by Lessee to be
made only by cashier's check. In the event of a Breach of this Lease by Lessee,
as defined in Paragraph 13.1, with or without further notice or demand, and
without limiting Lessor in the exercise of any right or remedy which Lessor may
have by reason of such Breach, Lessor may:

        (a) Terminate Lessee's right to possession of the Premises by any lawful
means, in which case this Lease and the term hereof shall terminate and Lessee
shall immediately surrender possession of the Premises to Lessor. In such event
Lessor shall be entitled to recover from Lessee, (i) the worth at the time of
the award of the unpaid rent which had been earned at the time of termination;
(ii) the worth at the time of award of the amount by which the unpaid rent which
would have been earned after termination until the time of award exceeds the
amount of such rental loss that the Lessee proves could have been reasonably
avoided; (iii) the worth at the time of award of the amount by which the unpaid
rent for the balance of the term after the time of award exceeds the amount of
such rental loss that the Lessee proves could be reasonably avoided; and (iv)
any other amount necessary to compensate Lessor for all the detriment
proximately caused by the Lessee's failure to perform its obligations under this
Lease or which in the ordinary course of things would be likely to result
therefrom, including but not limited to the cost of recovering possession of the
Premises, expenses of relating, including necessary renovation and alteration of
the Premises, reasonable attorneys' fees, and that portion of the leasing
commission paid by Lessor applicable to the unexpired term of this Lease. The
worth at the time of award of the amount referred to in provision (iii) of the
prior sentence shall be computed by discounting such amount at the discount rate
of the Federal Reserve Bank of San Francisco at the time of award plus one
percent. Efforts by Lessor to mitigate damages caused by Lessee's Default or
Breach of this Lease shall not waive Lessor's right to recover damages under
this Paragraph. If termination of this Lease is obtained through the provisional
remedy of unlawful detainer, Lessor shall have the right to recover in such
proceeding the unpaid rent and damages as are recoverable therein, or Lessor may
reserve therein the right to recover all or any part thereof in a separate suit
for such rent and/or damages. If a notice and grace period required under
subparagraphs 13.1(b), (c) or (d) was not previously given, a notice to pay rent
or quit, or to perform or quit, as the case may be, given to Lessee under any
statute authorizing the forfeiture of leases for unlawful detainer shall also
constitute the applicable notice for grace period purposes required by
subparagraphs 13.1(b), (c) or (d). In such case, the applicable grace period
under subparagraphs 13.1(b), (c) or (d) and under the unlawful detainer statute
shall run concurrently after the one such statutory notice, and the failure of
Lessee to cure the Default within the greater of the two such grace periods
shall constitute both an unlawful detainer and a Breach of this Lease entitling
Lessor to the remedies provided for in this Lease and/or by said statute.

        (b) Continue the Lease and Lessee's right to possession, in effect (in
California under California Civil Code Section 1951.4) after Lessee's Breach and
abandonment and recover the rent as it becomes due, provided Lessee has the
right to sublet or assign, subject only to reasonable limitations. See Paragraph
12 and 36 for the limitations on assignment and subletting which limitations
Lessee and Lessor agree are reasonable. Acts of maintenance or preservation,
efforts to relet the Premises, or the appointment of a receiver to protect the
Lessor's interest under the Lease, shall not constitute a termination of the
Lessee's right to possession.

        (c) Pursue any other remedy now or hereafter available to Lessor under
the laws or judicial decisions of the state wherein the Premises are located.

        (d) The expiration or termination of this Lease and/or the termination
of Lessee's right to possession shall not relieve Lessee from liability under
any indemnity provisions of this Lease as to matters occurring or accruing
during the term hereof or by reason of Lessee's occupancy of the Premises.

   13.3 INDUCEMENT RECAPTURE IN EVENT OF BREACH. Any agreement by Lessor for
free or abated rent or other charges applicable to the Premises, or for the
giving or paying by Lessor to or for Lessee of any cash or other bonus,
inducement or consideration for Lessee's entering into this Lease, all of which
concessions are hereinafter referred to as "INDUCEMENT PROVISIONS," shall be
deemed conditioned upon Lessee's full and faithful performance of all of the
terms, covenants and conditions of this Lease to be performed or observed by
Lessee during the term hereof as the same may be extended. Upon the occurrence
of a Breach of this Lease by Lessee, as defined in Paragraph 13.1, any such
Inducement Provision shall automatically be deemed deleted from this Lease and
of no further force or effect, and any rent, other charge, bonus, inducement or
consideration theretofore abated, given or paid by Lessor under such an
Inducement Provision shall be immediately due and payable by Lessee to Lessor,
and recoverable by Lessor as additional rent due under this Lease,
notwithstanding any subsequent cure of said Breach by Lessee. The acceptance by
Lessor of rent or the cure of the Breach which initiated the operation of this
Paragraph shall not be deemed a waiver by Lessor of the provisions of this
Paragraph unless specifically so stated in writing by Lessor at the time of such
acceptance.

   13.4 LATE CHARGES. Lessee hereby acknowledges that late payment by Lessee to
Lessor of rent and other sums due hereunder will cause Lessor to incur costs not
contemplated by this Lease, the exact amount of which will be extremely
difficult to ascertain. Such costs include, but are not limited to, processing
and accounting charges, and late charges which may be imposed upon Lessor by the
terms of any ground lease, mortgage or trust deed covering the Premises.
Accordingly, if any installment of rent or any other sum due from Lessee shall
not be received by Lessor or Lessor's designee within five (5) days after such
amount shall be due, then, without any requirement for notice to Lessee, Lessee
shall pay to Lessor a late charge equal to six percent (6%) of such overdue
amount. The parties hereby agree that such late charge represents a fair and
reasonable estimate of the costs Lessor will incur by reason of late payment by
Lessee. Acceptance of such late charge by Lessor shall in no event constitute a
waiver of Lessee's Default or Breach with respect to such overdue amount, nor
prevent Lessor from exercising any of the other rights and remedies granted
hereunder. In the event that a late charge is payable hereunder, whether or not
collected, for three (3) consecutive installments of Base Rent, then
notwithstanding Paragraph 4.1 or any other provision of this Lease to the
contrary, Base Rent shall, at Lessor's option, become due and payable quarterly
in advance.

   13.5 BREACH BY LESSOR. Lessor shall not be deemed in breach of this Lease
unless Lessor fails within a reasonable time to perform an obligation required
to be performed by Lessor. For purposes of this Paragraph 13.5, a reasonable
time shall be thirty (30) days after receipt by Lessor, and by the holders of
any ground lease, mortgage or deed of trust covering the Premises whose name and
address shall have been furnished Lessee in writing for such purpose, of written
notice specifying wherein such obligation of Lessor has not been performed;
provided, however, that if the nature of Lessor's obligation is such that more
than thirty (30) days after such notice are reasonably required for its
performance, then Lessor shall not be in breach of this Lease if performance is
commenced within such thirty (30) day period and thereafter diligently pursued
to completion.

14. CONDEMNATION. If the Premises or any portion thereof are taken under the
power of eminent domain or sold under the threat of the exercise of said power
(all of which are herein called "CONDEMNATION"), this Lease shall terminate as
to the part so taken as of the date the condemning authority takes title or
possession, whichever first occurs. If more than ten percent (10%) of the floor
area of the Premises, or more than twenty-five percent (25%) of the land area
not occupied by any building, is taken by condemnation, Lessee may, at Lessee's
option, to be exercised in writing within ten (10) days after Lessor shall have
given Lessee written notice of such taking (or in the absence of such notice,
within ten (10) days after the condemning authority shall

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have taken possession) terminate this Lease as of the date the condemning
authority takes such possession. If Lessee does not terminate this Lease in
accordance with the foregoing, this Lease shall remain in full force and
effect as to the portion of the Premises remaining, except that the Base Rent
shall be reduced in the same proportion as the rentable floor area of the
Premises taken bears to the total rentable floor area of the building located
on the Premises. No reduction of Base Rent shall occur if the only portion of
the Premises taken is land on which there is no building. Any award for the
taking of all or any part of the Premises under the power of eminent domain
or any payment made under threat of the exercise of such power shall be the
property of Lessor, whether such aware shall be made as compensation for
diminution in value of the leasehold or for the taking of the fee, or as
severance damages; provided, however, the Lessee shall be entitled to any
compensation, separately awarded to Lessee for Lessee's relocation expenses
and/or loss of Lessee's Trade Fixtures. In the event that this Lease is not
terminated by reason of such condemnation, Lessor shall to the extent of its
net severance damages received, over and above the legal and other expenses
incurred by Lessor in the condemnation matter, repair any damage to the
Premises caused by such condemnation, except to the extent that Lessee has
been reimbursed therefor by the condemning authority. Lessee shall be
responsible for the payment of any amount in excess of such net severance
damages required to complete such repair.

15. BROKER'S FEE.

    15.1 The Brokers named in Paragraph 1.10 are the procuring causes of this
Lease.

    15.5 Lessee and Lessor each represent and warrant to the other that it has
had no dealings with any person, firm, broker or finder (other than the Brokers,
if any named in Paragraph 1.10) in connection with the negotiation of this
Lease and/or the consummation of the transaction contemplated hereby, and that
no broker or other person, firm or entity other than said named Brokers is
entitled to any commission or finder's fee in connection with said transaction.
Lessee and Lessor do each hereby agree to indemnify, protect, defend and hold
the other harmless from and against liability for compensation or charges which
may be claimed by any such unnamed broker, finder or other similar party by
reason of any dealings or actions of the Indemnifying Party, including any
costs, expenses, attorneys' fees reasonably incurred with respect thereto.

   15.6 Lessor and Lessee hereby consent to and approve all agency
relationships, including any dual agencies, indicated in Paragraph 1.10.

16. TENANCY STATEMENT.

    16.1 Each Party (as "RESPONDING PARTY") shall within ten (10) days after
written notice from the other Party (the "REQUESTING PARTY") execute,
acknowledge and deliver to the Requesting Party, a statement in writing in form
similar to the then most current "TENANCY STATEMENT" form published by the
American Industrial Real Estate Association, plus such additional information,
confirmation and/or statements as may be reasonably requested by the Requesting
Party.

    16.2 If Lessor desires to finance, refinance, or sell the Premises, any part
thereof, or the building of which the Premises are a part, Lessee and all
Guarantors of Lessee's performance hereunder shall deliver to any potential
lender or purchaser designated by Lessor such financial statements of Lessee and
such Guarantors as may be reasonably required by such lender or purchaser,
including but not limited to Lessee's financial statements for the past three
(3) years. All such financial statements shall be received by Lessor and such
lender or purchaser in confidence and shall be used only for the purposes herein
set forth.

17. LESSOR'S LIABILITY. The term "LESSOR" as used herein shall mean the owner
or owners at the time in question of the fee title to the Premises, or, if
this is a sublease, of the Lessee's interest in the prior lease. In the event
of a transfer of Lessor's title or interest in the Premises or in this Lease,
Lessor shall deliver to the transferee or assignee (in cash or by credit) any
unused Security Deposit held by Lessor at the time of such transfer or
assignment. Except as provided in Paragraph 15, upon such transfer or
assignment and delivery of the Security Deposit, as aforesaid, the prior
Lessor shall be relieved of all liability with respect to the obligations
and/or covenants under this Lease thereafter to be performed by the Lessor.
Subject to the foregoing, the obligations and/or covenants in this Lease to
be performed by the Lessor shall be binding only upon the Lessor as
hereinabove defined.

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

19. INTEREST OR PAST-DUE OBLIGATIONS. Any monetary payment due Lessor
hereunder, other than late charges, not received by Lessor within thirty (30)
days following the date on which it was due, shall bear interest from the
thirty-first (31st) day after it was due at the rate of 12% per annum, but
not exceeding the maximum rate allowed by law, in addition, to the late
charge provided for in Paragraph 13.4.

20. TIME OF ESSENCE. Time is of the essence with respect to the performance
of all obligations to be performed or observed by the Parties under this
Lease.

21. RENT DEFINED. All monetary obligations of Lessee to Lessor under the
terms of this Lease are deemed to be rent.

22. NO PRIOR OR OTHER AGREEMENTS; BROKER DISCLAIMER. This Lease contains all
agreements between the Parties with respect to any matter mentioned herein, and
no other prior or contemporaneous agreement or understanding shall be effective.
Lessor and Lessee each represents and warrants to the Brokers that it has
made, and is relying solely upon, its own investigation as to the nature,
quality, character and financial responsibility of the other Party to this Lease
and as to the nature, quality and character of the Premises. Brokers have no
responsibility with respect thereto or with respect to any default or breach
hereof by either Party.

23. NOTICES.

    23.1 All notices required or permitted by this Lease shall be in writing
and may be delivered in person (by hand or by messenger or courier service)
or may be sent regular, certified or registered mail or U.S. Postal Service
Express Mail, with postage prepaid, or by facsimile transmission, and shall
be deemed sufficiently given if served in a manner specified in this
Paragraph 23. The addresses noted adjacent to a Party's signature on this
Lease shall be that Party's address for delivery or mailing of notice
purposes. Either Party may be written notice to the other specify a different
address for notice purposes, except that upon Lessee's taking possession of
the Premises, the Premises shall constitute Lessee's address for the purpose
of mailing or delivering notices to Lessee. A copy of all notices required or
permitted to be given to Lessor hereunder shall be concurrently transmitted
to such party or parties at such addresses as Lessor may from time to time
hereafter designate by written notice to Lessee.

   23.2 Any notice sent by registered or certified mail, return receipt
requested, shall be deemed given on the date of delivery shown on the receipt
card, or if no delivery date is shown, the postmark thereon. If sent by regular
mail the notice shall be deemed given forty-eight (48) hours after the same is
addressed as required herein and mailed with postage prepaid. Notices delivered
by United States Express Mail or overnight courier that guarantees next day
delivery shall be deemed given twenty-four (24) hours after delivery of the
same to the United States Postal Service or courier. If any notice is
transmitted by facsimile transmission or similar means, the same shall be deemed
served or delivered upon telephone confirmation of receipt of the transmission
thereof, provided a copy is also delivered via delivery or mail. If notice is
received on a Sunday or legal holiday, it shall be deemed received on the next
business day.

24. WAIVERS. No waiver by Lessor of the Default or Breach of any term,
covenant or condition hereof by Lessee, shall be deemed a waiver of any other
term, covenant or condition hereof, or of any subsequent Default or Breach by
Lessee of the same or any other term, covenant or condition hereof. Lessor's
consent to, or approval of, any act shall not be deemed to render unnecessary
the obtaining of Lessor's consent to, or approval of, any subsequent or
similar act by Lessee, or be construed as the basis of an estoppel to enforce
the provision or provisions of this Lease requiring such consent. Regardless
of Lessor's knowledge of a Default or Breach at the time of accepting rent,
the acceptance of rent by Lessor shall not be a waiver of any preceding
Default or Breach of Lessee of any provision hereof, other than the failure
of Lessee to pay the particular rent so accepted. Any payment given Lessor by
Lessee may be accepted by Lessor on account of moneys or damages due Lessor,
notwithstanding any qualifying statements or conditions made by Lessee in
connection therewith, which such statements and/or conditions shall be of no
force or effect whatsoever unless specifically agreed to in writing by Lessor
at or before the time of deposit of such payment.

25. RECORDING. Either Lessor or Lessee shall, upon request of the other,
execute, acknowledge and deliver to the other a short form memorandum of this
Lease for recording purposes. The Party requesting recordation shall be
responsible for payment of any fees or taxes applicable thereto.

26. NO RIGHT TO HOLDOVER. Lessee has no right to retain possession of the
Premises or any part thereof beyond the expiration or earlier termination of
this Lease.

27. CUMULATIVE REMEDIES. No remedy or election hereunder shall be deemed
exclusive but shall, wherever possible, be cumulative with all other remedies
at law or in equity.

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28. COVENANTS AND CONDITIONS. All provisions of this Lease to be observed
or performed by Lessee are both covenants and conditions.

28. BINDING EFFECT; CHOICE OF LAW. This Lease shall be binding upon the parties,
their personal representatives, successors and assigns and be governed by the
laws of the State in which the Premises are located. Any litigation between the
Parties hereto concerning this Lease shall be initiated in the county in which
the Premises are located.

30. SUBORDINATION; ATTORNMENT; NON-DISTURBANCE.

    30.1 SUBORDINATION. This Lease and any Option granted hereby shall be
subject and subordinate to any ground lease, mortgage, deed of trust, or other
hypothecation or security device (collectively, "SECURITY DEVICE"), now or
hereafter placed by Lessor upon the real property of which the Premises are a
part, to any and all advances made on the security thereof, and to all renewals,
modifications, consolidations, replacements and extensions thereof. Lessee
agrees that the Lenders holding any such Security Device shall have no duty,
liability or obligation to perform any of the obligations of Lessor under this
Lease, but that in the event of Lessor's default with respect to any such
obligation, Lessee will give any Lender whose name and address have been
furnished Lessee in writing for such purpose notice of Lessor's default and
allow such Lender thirty (30) days following receipt of such notice for the cure
of said default before invoking any remedies Lessee may have by reason thereof.
If any Lender shall elect to have this Lease and/or any Option granted hereby
superior to the lien of its Security Device and shall given written notice
thereof to Lessee, this Lease and such Options shall be deemed prior to such
Security Device, notwithstanding the relative dates of the documentation or
recordation thereof.

   30.2 ATTORNMENT. Subject to the non-disturbance provisions of Paragraph 30.3,
Lessee agrees to attorn to a Lender or any other party who acquires ownership of
the Premises by reason of a foreclosure of a Security Device, and that in the
event of such foreclosure, such new owner shall not: (i) be liable for any act
or omission of any prior lessor or with respect to events occurring prior to
acquisition of ownership (ii) be subject to any offsets or defenses which Lessee
might have against any prior lessor, (iii) to be bound by prepayment of more
than one months' rent.

   30.3 NON-DISTURBANCE. With respect to Security Devices entered into by Lessor
after the execution of this Lease, Lessee's subordination of this Lease shall be
subject to receiving assurance (a "NON-DISTURBANCE AGREEMENT") from the Lender
that Lessee's possession and this Lease, including any options to extend the
term hereof, will not be disturbed so long as Lessee is not in Breach hereof and
attorns to the record owner of the Premises.

   30.4 SELF-EXECUTING. The agreements contained in this Paragraph 30 shall be
effective without the execution of any further documents, provided, however,
that, upon written request from Lessor or a Lender in connection with a sale,
financing or refinancing of the Premises, Lessee and Lessor shall execute such
further writings as may be reasonably required to separately document any such
subordination or non-subordination, attornment and/or non-disturbance agreement
as is provided for herein.

31. ATTORNEY'S FEES. If any Party or Broker brings an action or proceeding to
enforce the terms hereof or declare rights hereunder, the Prevailing Party
(as hereafter defined) or Broker in any such proceeding, action, or appeal
thereon, shall be entitled to reasonable attorney's fees. Such fees may be
awarded in the same suit or recovered in a separate suit, whether or not such
action or proceeding is pursued to decision or judgment. The term,
"PREVAILING PARTY" shall include, without limitation, a Party or Broker who
substantially obtains of defeats the relief sought, as the case may be,
whether by compromise, settlement, judgment, or the abandonment by the other
Party or Broker of its claim or defense. The attorney's fee award shall not
be computed in accordance with any court fee schedule, but shall be such as
to fully reimburse all attorney's fees reasonably incurred. Lessor shall be
entitled to attorney's fees, costs and expenses incurred in the preparation
and service of notices of Default and consultations in connection therewith,
whether or not a legal action is subsequently commenced in connection with
such Default or resulting Breach.

32. LESSOR'S ACCESS; SHOWING PREMISES; REPAIRS. Lessor and Lessor's agents shall
have the right to enter the Premises at any time, in the case of an emergency,
and otherwise at reasonable times for the purpose of showing the same to
prospective purchasers, lenders, or lessees, and making such alterations,
repairs, improvements or additions to the Premises or to the building of which
they are a part, as Lessor may reasonably deem necessary. Lessor may at any time
place on or about the Premises or building any ordinary "For Sale" signs and
Lessor may at any time during the last one hundred twenty (120) days of the term
hereof place on or about the Premises any ordinary "For Lease" signs. All such
activities of Lessor shall be without abatement of rent or liability to Lessee.

33. AUCTIONS. Lessee shall not conduct, nor permit to be conducted, either
voluntarily or involuntarily, any auction upon the Premises without first having
obtained Lessor's prior written consent. Notwithstanding anything to the
contrary in this Lease, Lessor shall not be obligated to exercise any standard
of reasonableness in determining whether to grant such consent.

34. SIGNS. Lessee shall not place any sign upon the Premises, except that
Lessee may, with Lessor's prior written consent, install (but not on the
roof) such signs as are reasonably required to advertise Lessee's own
business. The installation of any sign on the Premises by or for Lessee shall
be subject to the provisions of Paragraph 7 (Maintenance, Repairs, Utility
Installation, Trade Fixtures and Alterations).

35. TERMINATION; MERGER. Unless specifically stated otherwise in writing by
Lessor, the voluntary or other surrender of this Lease by Lessee, the mutual
termination or cancellation hereof, or a termination hereof by Lessor for Breach
by Lessee, shall automatically terminate any sublease or lesser estate in the
Premises; provided, however, Lessor shall, in the event of any such surrender,
termination or cancellation, have the option to continue any one or all of any
existing subtenancies. Lessor's failure within ten (10) days following any such
event to make a written election to the contrary by written notice to the holder
of any such lesser interest, shall constitute Lessor's election to have such
event constitute the termination of such interest.

36. COVENANTS.

        (a) Except for Paragraph 33 hereof (Auctions) or as otherwise
provided herein, wherever in this Lease the consent of a Party is required to
an act by or for the other Party, such consent shall not be unreasonably
withheld or delayed. Lessor's actual reasonable costs and expenses (including
but not limited to architects', attorneys', engineers' or other consultants'
fees) incurred in the consideration of, or response to, a request by Lessee
for any Lessor consent pertaining to this Lease or the Premises, including but
not limited to consents to an assignment, a subletting or the presence or use
of a Hazardous Substance, practice or storage tank, shall be paid by Lessee
to Lessor upon receipt of an invoice and supporting documentation therefor.
Subject to Paragraph 12.2(e) (applicable to assignment or subletting), Lessor
may, as a condition to considering any such request by Lessee, require that
Lessee deposit with Lessor an amount of money (in addition to the Security
Deposit held under Paragraph 5) reasonably calculated by Lessor to represent
the cost Lessor will incur in considering and responding to Lessee's request.
Except as otherwise provided, any unused portion of said deposit shall be
refunded to Lessee without interest. Lessor's consent to any act, assignment
of this Lease or subletting of the Premises by Lessee shall not constitute an
acknowledgment that no Default or Breach by Lessee of this Lease exists, nor
shall such consent be deemed a waiver of any then existing Default or Breach,
except as may be otherwise specifically stated in writing by Lessor at the
time of such consent.

        (b) All conditions to Lessor's consent authorized by this Lease are'
acknowledged by Lessee as being reasonable. The failure to specify herein any
particular condition to Lessor's consent shall not preclude the imposition by
Lessor at the time of consent of such further or other conditions as are then
reasonable with reference to the particular matter for which consent is being
given.
* Lessor shall provide an estimate of such costs to Lessee for Lessee's
  reasonable approval prior to incurring such costs and shall negotiate
  in good faith to resolve any differences with respect to such costs prior to
  incurring such costs or considering the request for consent.

37. GUARANTOR.

    37.1 If there are to be any Guarantors of this Lease per Paragraph 1.11, the
form of the guaranty to be executed by each such Guarantor shall be in the form
most recently published by the American Industrial Real Estate Association, and
each said Guarantor shall have the same obligations as Lessee under this Lease,
including but not limited to the obligation to provide the Tenancy Statement and
Information called for by Paragraph 16.

    37.2 It shall constitute a Default of the Lessee under this Lease if any
such Guarantor fails or refuses, upon reasonable request by Lessor to give (a)
evidence of the due execution of the guaranty called for by this Lease,
including the authority of the Guarantor (and of the party signing on
Guarantor's behalf) to obligate such Guarantor on said guaranty, and including
in the case of a corporate Guarantor, a certified copy of a resolution of its
board of directors authorizing the making of such guaranty, together with a
certificate of incumbency showing the signatures of the persons authorized to
sign on its behalf, (b) current financial statements of Guarantor as may from
time to time be requested by Lessor, (c) a Tenancy Statement, or (d) written
confirmation that the guaranty is still in effect.

38. QUIET POSSESSION. Upon payment by Lessee of the rent for the Premises and
the observance and performance of all of the covenants, conditions and
provisions on Lessee's part to be observed and performed under this Lease,
Lessee shall have quiet possession of the Premises for the entire term hereof
subject to all of the provisions of this Lease.

39. OPTIONS.

    39.1 DEFINITION. As used in this Paragraph 39 the word "OPTION" has the
following meaning: (a) the right to extend the term of this Lease or to renew
this Lease or to extend or renew any lease that Lessee has on other property of
Lessor; (b) the right of first refusal to lease the Premises or the right of
first offer to lease the Premises or the right of first refusal to lease other
property of Lessor or the right of first offer to lease other property of
Lessor; (c) the right to purchase the Premises, or the right of first refusal to
purchase the Premises, or the right of first offer to purchase the Premises, or
the right to purchase other property of Lessor, or the right of first refusal to
purchase other property of Lessor, or the right of first offer to purchase other
property of Lessor.

   39.2 OPTIONS PERSONAL TO ORIGINAL LESSEE. Each Option granted to Lessee in
this Lease is personal to the original Lessee named in Paragraph 1.x hereof,
and cannot be voluntarily or involuntarily assigned or exercised by any
person or entity other than said original Lessee while the original Lessee is
in full and actual possession of the Premises and without the intention of
thereafter assigning or subletting. The Options, if any, herein granted to
Lessee are not assignable, either as a part of an assignment of this Lease or
separately or apart therefrom, and no Option may be separated from this Lease
in any manner, by reservation or otherwise.

   39.3 MULTIPLE OPTIONS. In the event that Lessee has any multiple Options to
extend or renew this Lease, a later option cannot be exercised unless the prior
Options to extend or renew this Lease have been validly exercised.

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  39.4 EFFECT OF DEFAULT ON OPTIONS.

        (a) Lessee shall have no right to exercise an Option, notwithstanding
any provision in the grant of Option to the contrary: (i) during the period
commencing with the giving of any notice of Default under Paragraph 13.1 and
continuing until the noticed Default is cured, or (ii) during the period of time
any monetary obligation due Lessor from Lessee is unpaid (without regard to
whether notice thereof is given Lessee), or (iii) during the time Lessee is in
Breach of this Lease, or (iv) in the event that Lessor has given to Lessee three
(3) or more notices of Default under Paragraph 13.1, whether or not the Defaults
are cured, during the twelve (12) month period immediately preceding the
exercise of the Option.

        (b) The period of time within which an Option may be exercised shall
not be extended or enlarged by reason of Lessee's inability to exercise an
Option because of the provisions of Paragraph 39.4(a).

        (c) All rights of Lessee under the provisions of an Option shall
terminate and be of no further force or effect, notwithstanding Lessee's due and
timely exercise of the Option, if, after such exercise and during the term of
this Lease, (i) Lessee fails to pay to Lessor a monetary obligation of Lessee
for a period of thirty (30) days after such obligation becomes due (without any
necessity of Lessor to give notice thereof to Lessee), or (ii) Lessor gives to
Lessee three or more notices of Default under Paragraph 13.1 during any twelve
month period, whether or not the Defaults are cured, or (iii) if Lessee commits
a Breach of this Lease.

40. MULTIPLE BUILDINGS. If the Premises are part of a group of buildings
controlled by Lessor, Lessee agrees that it will abide by, keep and observe all
reasonable rules and regulations which Lessor may make from time to time for the
management, safety, care, and cleanliness of the grounds, the parking and
unloading of vehicles and the preservation of good order, as well as the
convenience of other occupants or tenants of such other buildings and their
invitees, and that Lessee will pay its fair share of common expenses incurred in
connection therewith.

41. SECURITY MEASURES. Lessee hereby acknowledges that the rental payable to
Lessor hereunder does not include the cost of guard service or other security
measures, and that Lessor shall have no obligation whatsoever to provide same.
Lessee assumes all responsibility for the protection of the Premises, Lessee,
its agents and invitees and their property from the acts of third parties.

42. RESERVATIONS. Lessor reserves to itself the right, from time to time, to
grant, without the consent or joinder of Lessee, such easements, rights and
dedications that Lessor deems necessary, and to cause the recordation of parcel
maps and restrictions, so long as such easements, rights, dedications, maps and
restrictions do not unreasonably interfere with the use of the Premises by
Lessee. Lessee agrees to sign any documents reasonably requested by Lessor to
effectuate any such easement rights, dedication, map or restrictions.

4.3 PERFORMANCE UNDER PROTEST. If at any time a dispute shall arise as to any
amount or sum of money to be paid by one Party to the other under the provisions
hereof, the Party against whom the obligation to pay the money is asserted shall
have the right to make payment "under protest" and such payment shall not be
regarded as a voluntary payment and there shall survive the right on the part of
said Party to institute suit for recovery of such sum. If it shall be adjudged
that there was no legal obligation on the part of said Party to pay such sum or
any part thereof, said Party shall be entitled to recover such sum or so much
thereof as it was not legally required to pay under the provisions of this
Lease.

4.4 AUTHORITY. If either Party hereto is a corporation, trust, or general or
limited partnership, each individual executing this Lease on behalf of such
entity represents and warrants that he or she is duly authorized to execute and
deliver this Lease on its behalf. If Lessee is a corporation, trust or
partnership, Lessee shall, within thirty (30) days after request by Lessor,
deliver to Lessor evidence satisfactory to Lessor of such authority.

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

46. OFFER. Preparation of this Lease by Lessor or Lessor's agent and submission
of same to Lessee shall not be deemed an offer to lease to Lessee.  This Lease
is not intended to be binding until executed by all Parties hereto.

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

48. MULTIPLE PARTIES. Except as otherwise expressly provided herein, if more
than one person or entity is named herein as either Lessor or Lessee, the
obligations of such multiple parties shall be the joint and several
responsibility of all persons or entities named herein as such Lessor or
Lessee.

LESSOR AND LESSEE HAVE CAREFULLY READ AND REVIEWED THIS LEASE AND EACH TERM AND
PROVISION CONTAINED HEREIN, AND BY THE EXECUTION OF THIS LEASE SHOW THEIR
INFORMED AND VOLUNTARY CONSENT THERETO. THE PARTIES HEREBY AGREE THAT, AT THE
TIME THIS LEASE IS EXECUTED, THE TERMS OF THIS LEASE ARE COMMERCIALLY REASONABLE
AND EFFECTUATE THE INTENT AND PURPOSE OF LESSOR AND LESSEE WITH RESPECT TO THE
PREMISES.

        IF THIS LEASE HAS BEEN FILLED IN, IT HAS BEEN PREPARED FOR SUBMISSION TO
        YOUR ATTORNEY FOR HIS APPROVAL. FURTHER, EXPERTS SHOULD BE CONSULTED TO
        EVALUATE THE CONDITION OF THE PROPERTY AS TO THE POSSIBLE PRESENCE OF
        ASBESTOS, STORAGE TANKS OR HAZARDOUS SUBSTANCES. NO REPRESENTATION OR
        RECOMMENDATION IS MADE BY THE AMERICAN INDUSTRIAL REAL ESTATE
        ASSOCIATION OR BY THE REAL ESTATE BROKER(S) OR THEIR AGENTS OR EMPLOYEES
        AS TO THE LEGAL SUFFICIENCY, LEGAL EFFECT, OR TAX CONSEQUENCES OF THIS
        LEASE OR THE TRANSACTION TO WHICH IT RELATES; THE PARTIES SHALL RELY
        SOLELY UPON THE ADVICE OF THEIR OWN COUNSEL AS TO THE LEGAL AND TAX
        CONSEQUENCES OF THIS LEASE. IF THE SUBJECT PROPERTY IS LOCATED IN A
        STATE OTHER THAN CALIFORNIA, AN ATTORNEY FROM THE STATE WHERE THE
        PROPERTY IS LOCATED SHOULD BE CONSULTED.

The parties hereto have executed this Lease at the place on the dates specified
above to their respective signatures.

Executed at Carlsbad, CA                  Executed at Carlsbad, CA
            -------------------------                 -----------------------
on October 11, 1999                       on October 8, 1999
   ----------------------------------        --------------------------------
by LESSOR:                                by LESSEE:

BLACKMORE SIGNAL HILL, A CALIFORNIA       INVITROGEN CORPORATION
-------------------------------------     -----------------------------------
LIMITED PARTNERSHIP
--------------------------------------    -----------------------------------

By /s/ Allen J. Blackmore                 By /s/ James R. Guyan
   -----------------------------------       --------------------------------
Name Printed: Allen J. Blackmore          Name Printed: James R. Guyan
              ------------------------                  ---------------------
Title: General Partner                    Title: EVP/CEO
       -------------------------------           ----------------------------

By                                        By /s/ Warner R. Broaddus
  ------------------------------------       --------------------------------
Name Printed:                             Name Printed: Warner R. Broaddus
             -------------------------                 ----------------------
Title:                                    Title: General Counsel & Secretary
      --------------------------------           ----------------------------

Address: 1530 Faraday Avenue, Suite 170   Address: 1600 Faraday Avenue
         Carlsbad, California 92008                Carlsbad, California 92008
         ------------------------------            --------------------------
         Tel. No. (760) 804-9600                   Tel. No. (760) 603-7200
         ------------------------------            --------------------------
         Fax. No. (760) 804-9607                   Fax. No. (760) 603-7201
         ------------------------------            --------------------------

Physical
Mailing Address: P.O. Box 1810
                 Rancho Santa Fe, CA 92067

NET                                                PAGE 10

NOTICE: These forms are often modified to meet changing requirements of law
        and industry needs. Always write or call to make sure you are utilizing
        the most current form: American Industrial Real Estate Association,
        345 South Figueroa Street, Suite M-1, Los Angeles, CA 90071.
        (213) 687-6777. Fax No. (213) 687-8616.

       (C) COPYRIGHT 1990--BY AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION.
                                ALL RIGHTS RESERVED.

<PAGE>

       ADDENDUM TO STANDARD INDUSTRIAL/COMMERCIAL SINGLE-TENANT LEASE--NET
                                BY AND BETWEEN
         BLACKMORE SIGNAL HILL, A CALIFORNIA LIMITED PARTNERSHIP, LESSOR
                                      AND
                         INVITROGEN CORPORATION, LESSEE
                             DATED OCTOBER 7, 1999
================================================================================

49.     EARLY POSSESSION: Lessee shall be granted "Early Possession" of the
Premises during Lessor's construction of the shell building in order to
commence installation of Utility Installations, telephone lines, computer
cables, security systems and other Alterations. Lessee shall complete its
work following Lessor's completion of the shell building at which time Lessor
shall deliver the shell building to Lessee. The Commencement Date shall not
occur before twelve (12) weeks after Lessor completes the shell building,
expect with respect to Delay Days as described in Exhibit B.

50.     BASE RENT ADJUSTMENT: Lessor, simultaneously with the construction of
the shell building for the Premises, intends to construct a shell building on
Lot 103 in the Carlsbad Research Center. Lessor intends to have a contractor
submit a separate bid for the construction of each building and subsequently
have the contractor submit a single bid for the construction of both shell
buildings. If contractor actually achieves a cost reduction in the
construction of the two shell buildings (as determined following the
substantial completion of the two shell buildings), then the cost savings
shall be allocated between the two buildings based on the total square
footage of the two buildings. Each $1,000 in construction cost savings
allocated to the shell building for the Premises shall reduce the Base Rent
for the Premises by $10.00 per month.

51.     BASE RENT INCREASES: Annually on April 1, the monthly base rent
payable under paragraph 1.5 ("Base Rent") of the Lease shall be increased to
one hundred four percent (104%) times the rent payable for the month
immediately proceeding the date for rent adjustment.

52.     OPERATING EXPENSES: NOTWITHSTANDING ANYTHING TO THE CONTRARY
CONTAINED HEREIN, IN ADDITION TO THE MONTHLY BASE RENT, INSURANCE COSTS AND
PROPERTY TAXES FOR THE PREMISES, LESSEE SHALL REIMBURSE LESSOR FOR THE
FOLLOWING EXPENSES (a) THROUGH (f):
a.)     LANDSCAPE MAINTENANCE: Notwithstanding anything to the contrary
contained in Paragraph 7 of this Lease, it is understood by the parties hereto
that Lessor shall maintain the landscaping for the Building at Lessee's
expense. Lessor shall employ a landscaping contractor to maintain the
landscaping to include fertilizing, changing of annual colored flowers at
entrance, tree trimming and replacing of dead plants for the Building, and
Lessee shall reimburse Lessor monthly in addition to rent for such maintenance.
b.)     CRC COMMON AREA MAINTENANCE FEES: Notwithstanding anything to the
contrary contained in Paragraph 7 of this Lease, it is understood by the
parties hereto that there exists a monthly common area maintenance fee charged
by Carlsbad Research Center (CRC). Said maintenance for the Premises is
currently $ 199.35 per month, subject to increase.
c.)     ROOF INSPECTIONS: Notwithstanding anything to the contrary contained
in Paragraph 7 of this Lease, Lessor shall procure and maintain, at Lessee's
expense, a roof inspection contract, providing for bi-annual inspections of
the roof. Such inspection is currently $ 75.00 per inspection, subject to
increase.
d.)     FOSSIL FILTER MAINTENANCE: The on-site storm drain system is equipped
with one or more 6" continuous Storm Water Filtration System ("SWFS") to
effectively prohibit non-storm water discharges into the storm sewer.
Notwithstanding anything to the contrary contained in Paragraph 7 of this
Lease, Lessor shall procure and maintain, at Lessee's expense, a preventive
maintenance contract to inspect, service and maintain the fossil filter three
(3) times per year. The cost of this service is estimated to be $200.00 per
year per SWFS, subject to increase.
e.)     FIRE SPRINKLER TESTING AND CERTIFICATION: It is understood by the
parties hereto that the building is equipped with an automatic fire sprinkler
system, which according to state law, must be serviced and inspected
quarterly and certified every five (5) years. Notwithstanding anything to the
contrary contained in Paragraph 7 of this lease, Lessor shall procure and
maintain a fire sprinkler maintenance contract providing for the required
quarterly inspections and service and five (5) year certifications. Lessee
shall reimburse Lessor for these services.
f.)     NOTWITHSTANDING ANYTHING TO THE CONTRARY CONTAINED HEREIN, LESSEE
SHALL BE RESPONSIBLE FOR CONTRACTING DIRECTLY WITH THE FOLLOWING VENDORS FOR
THE OPERATING ITEMS LISTED BELOW AND SHALL PAY SAID VENDORS DIRECTLY:

(i.)     WATER: Lessee acknowledges that the Building is equipped with three (3)
         water meters (Building, Landscape and Fire Sprinkler). Lessee shall
         transfer the three water meter accounts into its name upon substantial
         completion of the shell building.

(ii.)    FIRE SPRINKLER MAINTENANCE/MONITORING: Notwithstanding anything to
         the contrary contained in Paragraph 7 of this Lease, it is understood
         by the parties hereto that the Building is equipped with a fire
         sprinkler alarm system for which Lessee shall be responsible. Upon
         substantial completion of the shell building, the existing contract
         with ADT Security shall be transferred into Invitrogen's name. Lessor
         shall have no liability to Lessee with respect to the fire sprinkler
         maintenance and monitoring equipment.

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(iii.)   HVAC MAINTENANCE: Notwithstanding anything to the contrary contained
in Paragraph 7 of this Lease, Lessee shall enter into an air conditioning
system maintenance contract with a vendor and on terms reasonably acceptable
to Lessor, providing for quarterly service. Lessee shall provide Lessor with
copies of such maintenance contract immediately following execution and shall
provide Lessor reasonable assurances that such maintenance is being
adequately performed by an acceptable third party vendor. If Lessee fails to
maintain such acceptable maintenance contract, then Lessor may enter into a
contract at Lessee's expense and Lessee shall reimburse Lessor for such
expense.

53.     PARKING: The parking areas of the property shall be used for parking
of automobiles, and the loading and unloading of trucks only. The use by
Lessee of those areas for long term storage of materials (including pallets)
is expressly prohibited and any temporary storage shall comply with the rules
and regulations of the Carisbad Research Center. All material shall be stored
within the Premises.

54.     ROOF MAINTENANCE: Lessee shall not take any action to cause the GAF
MATERIALS CORPORATION LIBERTY GUARANTEE attached hereto and made a part
hereof as Exhibit C of the Lease to become ineffective including, without
limitation, those actions described in items 5-8 in the "Exclusions From
Coverage" in such guarantee.

55.     OPTION TO EXTEND: Provided that Lessee is not in material Default
under any of the terms, covenants and conditions of the Lease and Lessor
has not provided Lessee with a notice of default that has not been cured,
Lessor hereby grants to Lessee, subject to the conditions hereinafter set
forth, one (1), five (5) year option to extend the term of this Lease. The
option shall be on such terms and conditions as this Lease, except for Base
Rent, which shall be adjusted as set forth below. This grant of an option
shall be of no force and effect unless Lessee gives Lessor written
notification of Lessee's intent to exercise the option by at least April 1,
2009 and not sooner than February 1, 2009.

56.     RENT ADJUSTMENTS DURING OPTION PERIOD: On October 1, 2010, the
monthly base rent due hereunder shall be adjusted to ninety-five percent
(95%) of the fair market rental value of the Premises as of October 1, 2010.
As used herein "fair market rental value" shall mean the projected prevailing
rental rate as of October 1, 2010 for similar commercial space situated in
the area of Carlsbad, California, but not taking into account prevailing
rental concessions, lessee improvement allowances and any other concessions
offered for such similar space as of such date. Lessor shall provide written
notice of such amount not later than three (3) months prior to the expiration
of the original lease term. Lessee shall thereafter have fifteen (15) days
("Lessee's Review Period") after receipt of Lessor's notice of the fair
market rental value within which to accept such fair market rental value or
to reasonably object thereto in writing.

In the event Lessee objects to the fair market rental value submitted by
Lessor, Lessor and Lessee shall attempt in good faith to agree upon such fair
market rental value, using their best good faith efforts. If Lessor and
Lessee fail to reach agreement on such fair market rental value within
fifteen (15) days following Lessee's Review Period (the "Outside Agreement
Date"), then the determination of fair market rental value shall be submitted
to arbitration under the provisions of the American Arbitration Association.
The cost of arbitration shall be paid by Lessor and Lessee equally.
Notwithstanding the fair market rental value for the Premises, in no event
shall the new monthly base rent be less than the monthly base rent payable
for the month immediately preceding the date for rent adjustment.

Thereafter, the monthly base rent shall be increased annually on October 1 of
each year in accordance with Paragraph 51 hereof.

                   "NOTICE: BY INITIALING THE SPACE BELOW YOU ARE
                    AGREEING TO HAVE ANY DISPUTE ARISING OUT OF THE
                    MATTERS INCLUDED IN THE 'ARBITRATION OF
                    DISPUTES' PROVISION CONTAINED IN THIS PARAGRAPH 56
                    DECIDED BY NEUTRAL ARBITRATION AS PROVIDED BY
                    CALIFORNIA LAW AND YOU ARE GIVING UP ANY RIGHTS
                    YOU MAY POSSESS TO HAVE THE DISPUTE LITIGATED
                    IN A COURT OR JURY TRIAL. BY INITIALING IN THE
                    SPACE BELOW YOU ARE GIVING UP YOUR JUDICIAL
                    RIGHTS TO DISCOVERY AND APPEAL, UNLESS SUCH
                    RIGHTS ARE SPECIFICALLY ALLOWED PURSUANT TO THE
                    PROVISIONS OF THE AMERICAN ARBITRATION ASSOCIATION.
                    IF YOU REFUSE TO SUBMIT TO ARBITRATION AFTER AGREEING
                    TO THIS PROVISION, YOU MAY BE COMPELLED TO
                    ARBITRATE UNDER THE AUTHORITY OF THE CALIFORNIA
                    CODE OF CIVIL PROCEDURE. YOUR AGREEMENT TO THIS
                    ARBITRATION PROVISION IS VOLUNTARY." "WE HAVE
                    READ AND UNDERSTAND THE FOREGOING AND AGREE TO
                    SUBMIT DISPUTES ARISING OUT OF THE MATTERS
                    INCLUDED IN PARAGRAPH 56 OF THIS LEASE TO
                    NEUTRAL ARBITRATION."
                              "Lessor"            "Lessee"

                                AJB                 WRB
                             -----------         -----------
                              Initials            Initials

57. EXHIBITS: The following exhibits are attached hereto and made a part
hereof:
                    Exhibit A -- Site Plan;
                    Exhibit B -- Construction Agreement;
                    Exhibit C -- Roof Guarantee;
                    Exhibit D -- Approved Hazardous Substances;
                    Exhibit E -- Shell Building Plans.

                                                      Initials      WRB
                                                                -----------
                                                                    AJB
                                                                -----------

                                    PAGE 12

<PAGE>

LESSOR:                                    LESSEE:

BLACKMORE SIGNAL HILL,                     INVITROGEN CORPORATION
A CALIFORNIA LIMITED PARTNERSHIP

By:  /s/ Allen J. Blackmore                By: /s/ JRG
   ------------------------------             --------------------------------
     Allen Joseph Blackmore, Trustee
     of the Blackmore Family Trust         Its: EVP/CFO
     Restated 1995, General Partner            -------------------------------
                                               (Title of Officer Signing Above)

                                           By: /s/ Warner R. Broaddus
                                              --------------------------------

                                           Its: General Counsel & Secretary
                                               --------------------------------
                                               (Title of Officer Signing Above)

Date:  Oct. 11, 1999                       Date: Oct. 8, 1999
     ----------------------------               -------------------------------

                                    PAGE 13

<PAGE>

                                  EXHIBIT A
                             1620 FARADAY AVENUE
                                   CARLSBAD

                                    [MAP]

                                FARADAY AVENUE

<PAGE>

                                   EXHIBIT "B"

                               CONSTRUCTION AGREEMENT

     This CONSTRUCTION AGREEMENT ("Agreement") is entered into as of
October__, 1999, by and between Blackmore Signal Hill, a California limited
partnership ("Lessor"), and Invitrogen Corporation ("Lessee") in connection
with the execution of that certain Standard Industrial/Commercial
Single-Tenant Lease-Net ("Lease") dated of even date herewith between Lessor
and Lessee, who agree as follows:

     1.   GENERAL.

          a.   The purpose of this Agreement is to set forth how the
improvements in the Premises ("Improvements") are to be constructed, who
will be responsible for the construction of the Improvements, who will pay
for the construction of the Improvements, and the time schedule for
completion of the construction of the Improvements. The parties intend that
Lessor shall enter into a contract with Reno Contracting, Inc. ("Contractor")
and have responsibility to construct the shell building ("Shell") and Lessee
will enter into a separate contract with Contractor and have responsibility to
construct the Lessee Improvements.

          b.   Except as otherwise defined in this Agreement, all terms
utilized in this Agreement shall have the same meaning as the defined terms
in the Lease.

          c.   The provisions of the Lease, except where clearly inconsistent
or inapplicable to this Agreement, are hereby incorporated into this
Agreement.

     2.   LESSOR'S WORK.

          a.   Following execution of the Lease, Lessor shall cause the Shell
to be built out and delivered to Lessee in accordance with those certain plans
("Shell Plans") prepared by Smith Consulting Architects ("Lessor's
Architect") with a drawing date of June 1, 1998, a copy of which is attached
to the Lease as Exhibit "E" ("Lessor Improvements") and in accordance with
industry custom and practice. Lessor shall be responsible for all costs of
the Shell and Lessee shall have no obligation with respect to the payment of
the cost of the construction of the Shell (except with respect to Change
Orders initiated by Lessee). Such costs shall include, without limitation, all
direct and indirect costs related to the architectural, engineering and
inspection fees, construction management fees, the costs of the Shell Plans
and working drawings, payments made under all construction contracts,
premiums for all bonds and insurance, all sales, use or similar taxes
relating to the construction of the Shell, permit fees and other governmental
fees relating to the construction of the Shell, losses and expenses not
compensated by insurance or otherwise sustained by Lessee, blueprinting
expenses and all other ordinary and reasonable expenses incurred applicable to
the construction of the Shell.

          b.   Lessor, Lessor's Architect and Contractor shall be
responsible for compliance with all applicable codes and regulations of duly
constituted authorities having jurisdiction as far as the construction of the
Shell is concerned and for all applicable safety regulations established by
Lessor, OSHA or other regulatory agencies. Lessor shall cause Lessee to be
named as an additional insured on an insurance policy carried by Lessor (or
Contractor

<PAGE>

pursuant to the shell construction contract between Lessor and Contractor)
with respect to third party damage claims related to the construction of the
Shell that occur during the construction of the Shell.

          c.   Lessee or Lessee's agents shall have the right to inspect the
construction of the Shell during the progress thereof, it being the intent of
the parties hereto that Lessee be reasonable in inspection of the Shell
construction and that Lessee shall recognize, to the extent commercially
reasonable and practicable, the necessity of field changes based on field
conditions. If Lessee shall give notice of faulty construction or any
deviation from Shell Plans immediately after such faulty construction or
deviation occurs, then Lessor shall cause Contractor to make corrections
promptly. However, neither the privilege herein granted to Lessee to make such
inspections, nor the making of such inspections by Lessee, shall operate as a
waiver of any rights of Lessee to require good and workmanlike construction
and improvements erected in accordance with the Shell Plans. No fee shall be
due hereunder for Lessee's inspection of the construction of the Shell.

     3.   LESSEE'S PLAN APPROVAL. Within ten calendar days following the
execution of the Lease, Lessee shall execute a contract with Pacific
Cornerstone Architects, Inc. ("Tenant's Architect") to prepare detailed plans
and specifications ("Lessee Improvement Plans"), which Lessee Improvement
Plans shall reflect the work to be performed within the Premises to suitably
prepare the Premises for Lessee's use ("Lessee Improvements"). The Lessee
Improvement Plans shall comply with all applicable laws, statutes, codes,
rules or regulations, including regulations and procedures for general safety
and the protection of the Premises and the surrounding project promulgated by
Lessor applicable to the construction of the Lessee Improvements, such
Lessor-promulgated rules to be reasonable in light of the simultaneous
construction of the Shell and the Lessee Improvements. Lessee and Tenant's
Architect shall cooperate with Lessor in providing specifications regarding
the Lessee Improvements so as not to delay the construction of the Shell.
Lessee shall use its best efforts to respond to Lessor's request regarding
the Lessee Improvements within five (5) business days of Lessor's request
(e.g. Lessee and Tenant's Architect shall use best efforts to notify Lessor,
within five (5) business days after Lessor's request, of the desired location
of the electrical, plumbing, sewer and other utilities prior to the pouring of
the foundation). Lessee shall incur a Delay Day for each day after five (5)
business days that Lessee fails to respond to Lessor's request with respect
to the Lessee Improvements. Lessee shall cause the Lessee Improvement Plans
to be delivered to Lessor as soon as reasonably possible following the
execution of the Lease and Lessor shall, within five (5) business days
following its receipt of the Lessee Improvement Plans, either approve such
Lessee Improvement Plans or provide Lessee in writing with the detailed
reasons that Lessor is withholding such consent. If Lessor provides neither
the prescribed approval nor disapproval with reasons within five (5)
business days, then the Lessee Improvement Plans will be deemed approved.
Lessor's objection to the Lessee Improvement Plans may include construction
times that extend substantially beyond those normally expected in office
construction in the Carlsbad Research Center. If Lessor does not approve the
Lessee Improvement Plans, Lessee shall immediately cause Tenant's Architect to
revise the Lessee Improvement Plans, consistent with Lessor's comments, and
then resubmit the Lessee Improvement Plans to Lessor for review within ten
business days of Lessor's notice to Lessee of said non-approval of the Lessee
Improvement Plans. Construction of the Lessee Improvements shall not commence
until Lessor has approved

                                        2

<PAGE>

the Lessee Improvement Plans and Tenant's Architect shall prepare all
specifications necessary for Contractor to build the Lessee Improvements
immediately following Lessor's approval of the Lessee Improvement Plans.
Construction of the Lessee Improvements shall strictly conform to the
approved Lessee Improvement Plans and any deviation will require Lessor's
prior approval of a Change Order. Each day of delay caused by Lessee's
failure to act or respond within the time for response pursuant to this
paragraph shall result in a Delay Day.

     4.   SIMULTANEOUS CONSTRUCTION.  The construction of the Lessee
Improvements shall occur during the construction of the Lessor Improvements;
provided, however, that Lessee shall not interfere with or delay Lessor in
its construction of the Shell.

     5.   DATE OF SUBSTANTIAL COMPLETION.  Lessor shall make reasonable
efforts in coordination with the Contractor to cause substantial completion of
the Shell on or before February 15, 2000, ("Anticipated Date of Substantial
Completion"), subject to delays from causes beyond the reasonable control of
Lessor, such as acts of God, strikes, work stoppages, unavailability or delay
in receiving permits, labor or materials, defaults by contractors or
subcontractors (to the extent such unavailability, delay or default was
reasonably unavoidable by Lessor), weather conditions, fire or other
casualty, or action of governmental authorities. Contractor shall reasonably
and in good faith determine the actual Date of Substantial Completion
pursuant to the standards contained in the Shell construction agreement
between Lessor and Contractor.

     6.   DELAY IN COMPLETION. If Lessee delays the Substantial Completion
Date due to interference with Lessor's completion of the construction of the
Shell, Change Orders or Lessee's (or Tenant's Architect) non-timely response
to clarification or direction requested by Lessor, Lessor's Architect or
Contractor, then Lessor shall reasonably and in good faith determine and
notify Lessee of the number of "Delay Days" Lessee's actions, or non-actions,
have caused to the construction schedule. The Date of Substantial Completion
shall be postponed by the number of Delay Days incurred, but the Commencement
Date shall occur twelve weeks after that date that the Date of Substantial
Completion would have occurred but for the Delay Days.

     7.   CONSTRUCTION OF LESSEE IMPROVEMENTS.

          a. Lessee, at its sole and entire cost, shall contract with
Contractor to construct the Lessee Improvements as indicated on the Lessee
Improvement Plans, consistent with industry custom and practice. Lessor shall
have no obligation with respect to the payment of the cost of the Lessee
Improvements and shall have the right to post a notice of non-responsibility
at the Premises. The cost of the Lessee Improvements shall include all direct
and indirect costs incurred to construct the Lessee Improvements, including,
without limitation, all direct and indirect costs related to the
architectural, engineering and inspection fees, construction management fees,
the costs of the Lessee Improvement Plans and working drawings, payments made
under all construction contracts, premiums for all bonds and insurance, all
sales, use or similar taxes relating to the construction of the Lessee
Improvements, permit fees and other governmental fees, losses and expenses
not compensated by insurance or otherwise sustained by Lessor, blueprinting
expenses and all other ordinary and reasonable expenses incurred applicable
to the construction of the Lessee Improvements. Lessee shall supervise
Contractor in the construction of the Lessee Improvements.

                                       3

<PAGE>

          b.   Lessee, Tenant's Architect and Contractor shall be responsible
for compliance with all applicable codes and regulations of duly constituted
authorities having jurisdiction as far as the performance of the Lessee
Improvements is concerned and for all applicable reasonable safety
regulations established by Lessor, OSHA or other regulatory agencies and
Lessee further agrees to save and hold Lessor harmless from Lessee's actions
arising from the Lessee Improvements.

          c.   Any modifications to the building exterior shall be subject to
Lessor's prior approval. All equipment placed upon the roof as a result of
the Lessee Improvements shall be approved by Lessor prior to the commencement
of the Lessee Improvements and shall comply with all governmental rules and
regulations and the provisions of the Lease. Lessee shall not make any
penetrations in the roof of the Premises without the prior consent of the
Lessor and Lessor's roof contractor or another roofing contractor approved to
make penetrations by the roofing warranty company shall perform all roof
penetrations so that the ten year roof warranty for the Premises is not voided
in any way.

          d.   Lessor or Lessor's agents shall have the right to inspect the
construction of the Lessee Improvements during the progress thereof, it being
the intent of the parties hereto that Lessor be reasonable in inspection of
the construction of work conducted by Lessee and that Lessor shall recognize,
to the extent commercially reasonable and practicable, the necessity of field
changes based on field conditions. If Lessor shall give notice of faulty
construction or any deviation from the Lessee Improvement Plans, then Lessee
shall cause Contractor to make corrections promptly. However, neither the
privilege herein granted to Lessor to make such inspections, nor the making
of such inspections by Lessor, shall operate as a waiver of any rights of
Lessor to require good and workmanlike construction and improvements
erected in accordance with the Lessee Improvement Plans. No fee shall be due
hereunder for Lessor's inspection of the Lessee Improvements.

     8.   CHANGE ORDERS.

          a.   If either party requests any changes to the Shell Plans or
Lessee Improvement Plans other than those due to acts or omissions of the
other or the other's Architect ("Change Order"), the non-requesting party
shall not unreasonably withhold its consent to any such Change Order,
provided the Change Order does not materially affect the Building's
structure, systems, equipment or appearance and does not result in the use
of materials in the construction of the Shell or Lessee Improvements of a
lesser quality than the materials shown on the Shell Plans or Lessee
Improvement Plans. Requests for Change Orders shall be in writing and the
non-requesting party shall use best efforts to respond within five (5)
business days. If no response is received within five (5) business days, then
the request shall be deemed approved. If a Change Order requested by Lessee
increases the cost of the Shell, then Lessor shall give notice to Lessee of
the increase amount, if any, at the time of Lessor's approval of the relevant
Change Order and Lessee, within fifteen (15) calendar days of Lessor's
request, shall pay to Lessor such increase in the cost of the Shell.

          b.   If a Change Order requested by Lessor after Lessor's approval
of the Lessee Improvement Plans increases the cost of the Lessee Improvements,
then Lessee shall give

                                       4

<PAGE>

notice to Lessor of the increase amount, if any, at the time of Lessor's
approval of the relevant Change Order and Lessor, within fifteen (15)
calendar days of Lessee's request, shall pay to Lessee such increase in the
cost of the Lessee Improvements.

     9.   LIMITS OF LIABILITY.

          a.   Lessor shall not be liable for any loss, cost, damage, or
expense incurred or claimed by Lessee or any other person or party on account
of the construction or installation of the Lessee Improvements or any other
improvements to the Premises made by Lessee, except to the extent caused by
Lessor's gross negligence, recklessness or intentional acts. Lessor shall not
be the guarantor of nor responsible for the correctness or accuracy of the
Lessee Improvement Plans or compliance of the Lessee Improvement Plans with
applicable laws. Lessor assumes no liability or responsibility resulting from
the failure of the Lessee to comply with applicable governmental laws, codes
and regulations or for any defect in any of the Lessee Improvements or other
alteration to the Premises made by Lessee. Lessee further agrees to
indemnify, defend, and hold harmless Lessor from any liability, loss, cost,
damage or expense incurred, claimed, asserted or arising in connection with
any of the foregoing.

          b.   Lessee shall not be liable for any loss, cost, damage, or
expense incurred or claimed by Lessor or any other person or party on account
of the construction or installation of the Shell Plans or any other
improvements to the Premises made by Lessor, except to the extent caused by
Lessee's gross negligence, recklessness or intentional acts. Lessee shall
not be the guarantor of nor responsible for the correctness or accuracy of
the Shell Plans or compliance of Shell Plans with applicable laws. Lessee
assumes no liability or responsibility resulting from the failure of the
Lessor to comply with applicable governmental laws, codes and regulations or
for any defect in any of the Shell or other alteration to the Premises made
by Lessor.

     10.  FUTURE IMPROVEMENTS BY LESSEE TO THE PREMISES.  In the event that
Lessee shall desire to perform future improvements to the Premises during the
term of the Lease or any extension thereof, Lessee shall construct such
improvements in accordance with the terms and conditions of the Lease.

     11.  DEFAULT.  Any default by Lessee or Lessor under the terms of this
Agreement shall constitute a default under the Lease and shall entitle the
other to exercise all remedies set forth in the Lease. The defaulting party
shall have all rights to remedy such default pursuant to the provisions of
the Lease.

     12.  REASONABLE DILIGENCE.  Both Lessor and Lessee agree to use
reasonable diligence in performing all of their respective obligations and
duties under this Agreement and in proceeding with the construction and
completion of all Improvements in the Premises.

     13.  LESSEE IMPROVEMENT COSTS.  If Lessee brings a successful action
against Lessor with respect to (i) early termination of the Lease due to
breach or Default of the Lessor, or (ii) the cancellation of the Lease due to
a Delay in Possession caused by the gross negligence, recklessness or
intentional acts or omissions of Lessor, then in awarding damages to Lessee, a

                                       5

<PAGE>

California court shall take into consideration the amounts Lessee expended
for the Lessee Improvements.

                                       LESSOR:

                                       BLACKMORE SIGNAL HILL,
                                       A California Limited Partnership

                                       By:   /s/ Allen J. Blackmore
                                          ------------------------------------
                                          Allen Joseph Blackmore, Trustee of
                                          the Blackmore Family Trust,
                                          Restated 1995, General Partner

                                       LESSEE:

                                       INVITROGEN CORPORATION

                                       By:  /s/ Warner Broaddus
                                          ------------------------------------

                                       Its: General Counsel & Secretary
                                          ------------------------------------

                                       By:
                                          ------------------------------------

                                       Its:
                                          ------------------------------------

                                       6

<PAGE>

[U.S. INTEC LOGO]                                             No. WENPN10-2536
                                                                  ------------

                                               NO DOLLAR LIMIT (NDL) GUARANTEE
                                               -------------------------------

TYPE OF GUARANTEE: NEW INTEC/PERMAGLAS NDL GUAR   PERIOD OF COVERAGE: 10 YEARS
                   ----------------------------                       --

OWNER: BLACKMORE SIGNAL HILL, CARLSBAD, CA 92008
       -----------------------------------------------------------------------

NAME AND TYPE OF BUILDING: LOT 98
                           ---------------------------------------------------

ADDRESS OF BUILDING:  1620 FARADAY AVE., CARLSBAD, CA 92008
                      --------------------------------------------------------

SPECIFICATION:  MB4UPN                           AREA OF ROOF: 120.00 SQUARES
                ------------------------------                 -------

TYPE OF FLASHING: 2XM                       LENGTH OF FLASHING 400 LINEAL FEET
                  ------------------------                     ---

APPLIED BY: SUPERIOR ROOFING / SAN MARCOS, CA
            ------------------------------------------------------------------

DATE OF COMPLETION: 07/04/2000                    EXPIRATION DATE:  07/04/2010
                    ----------------------------                   -----------

THE GUARANTEE

     U.S. INTEC, Inc. guarantees to the Building Owner that, subject to the
terms and conditions set forth below, U.S. INTEC will make those repairs to
the U.S. INTEC roofing membrane, base flashing, insulation, expansion joint
covers and pre-flashed accessories (the "U.S. INTEC Roofing Materials") used
in the construction of the above described roof as are necessary to correct
leaks while this Guarantee is in effect. This Guarantee covers such repairs
to the U.S. INTEC Roofing Materials (excluding repair or replacement of roof
deck, insulation, or other materials used in conjunction with the roofing
system not sold by U.S. INTEC) as shall be necessary solely in order to
correct leaks resulting from any of the causes listed below. These repairs
will be made at no cost to the Building Owner provided that the Owner gives
timely written notice to U.S. INTEC (see below).

SCOPE OF COVERAGE - LEAKS CAUSED BY:

1. Natural deterioration of the U.S. INTEC Roofing Materials.
2. Blisters
3. Bare Spots
4. Fish-mouths
5. Ridges
6. Splits not caused by structural failure or movement of or cracks in
   substrate roof base or non-U.S. INTEC insulation over which the U.S.
   INTEC Roofing Materials are applied.
7. Buckles and wrinkles
8. Workmanship in applying the U.S. INTEC Roofing Materials
9. Slippage of membrane or base flashing

OWNER'S RESPONSIBILITIES

     In the event of a leak through the U.S. INTEC Roofing Materials, the
Owner must notify the U.S. INTEC Contractor Services Department, 1361 Alps
Road, Bldg. 7-B, Wayne, New Jersey 07470 in writing within THIRTY days after
discovery of the leak. The roofing contractor is NOT an agent of U.S. INTEC;
notice to the roofing contractor is NOT notice to U.S. INTEC.

     The Owner shall, at its expense, (a) perform regular inspections and
maintenance during this Guarantee, (b) keep records of all inspections and
maintenance performed, and (c) perform repairs to the roof or other building
components identified during inspections by U.S. INTEC as being necessary to
preserve the integrity of the U.S. INTEC Roofing Materials. Failure of the
Owner to perform this work promptly following written notification by U.S.
INTEC may result in cancellation of this guarantee if the Owner's failure
results in damage to the U.S. INTEC Roofing Materials.

     The Owner shall, at its expense, remove (and, if desired, subsequently
replace) any materials and equipment that impede inspection and repair of the
U.S. INTEC Roofing Materials, such as HVAC units and satellite dishes mounted
so that there is no functional access to the roof system, and precast
concrete or rubber pavers, wood decking and steel grating that are installed
over the U.S. INTEC Roofing Materials.

     In an emergency, the Owner may authorize or perform temporary repairs to
minimize damage to the building or its contents. Such work will not result in
the cancellation of this Guarantee provided that the temporary repairs are
reasonable and customary, and do not result in permanent damage to the U.S.
INTEC Roofing Materials. The Owner is responsible for all expenses associated
with temporary repairs.

EXCLUSIONS FROM COVERAGE

This Guarantee shall NOT cover the following conditions or any damages which
may arise therefrom.

1.  Roof maintenance or correction of conditions other than leaks.

2.  Unusual weather conditions or natural disasters including, but not
    limited to, windstorms, hail, floods, hurricanes, lightning, tornados
    and earthquakes.

3.  Damage to the roof constructed of the U.S. INTEC Roofing Materials
    due to: (a) settlement, distortion, movement, failure or cracking of the
    roof deck, walls, or foundations of the building; (b) improper
    installation of non-U.S. INTEC insulation or defects or failure of any
    material used in any roof base or insulation not manufactured by U.S.
    INTEC over which the U.S. INTEC Roofing Materials are applied; (c)
    infiltration or condensation of moisture in, through or around the
    walls, copings, building structure, or underlying or surrounding
    materials including tie-ins to adjacent roof systems; (d) defects in
    design; (e) the performance, design, or application of non-U.S. INTEC
    materials such as roof decks, metal work, expansion and control joints,
    pitch pockets, walkways, work platforms and recreational surfacings; (f)
    expansion or contraction of any metal flashing or other metal work; (g)
    underlying materials or structures having failed or ceased to conform to
    U.S. INTEC's or other applicable specifications as to roof slopes or
    other requirements; (h) chemical attack on the membrane; (i) vandalism;
    or (j) negligence by the Owner in maintaining the U.S. INTEC Roofing
    Materials.

4.  Damage to the building or its contents.

5.  Changes in usage of the building unless approved in writing in advance by
    U.S. INTEC.

6.  Damage resulting from any new installations on or through the U.S. INTEC
    Roofing Materials or from traffic of any nature on the roof.

7.  Temporary repairs to the U.S. INTEC Roofing Materials authorized by the
    Owner.

8.  Any repairs or other applications to the U.S. INTEC Roofing Materials
    after the date of completion, unless performed in a manner acceptable to
    and approved by U.S. INTEC in writing in advance. NOTE: In no event shall
    new penetrations be covered under the terms of guarantee.

9.  Any damage occurring more than thirty days after the discovery by the Owner
    or its agent of a leak, unless U.S. INTEC is notified of such leak within
    thirty days of its discovery.

10. Areas of roof which pond water.

     No representative, employee, or agent of U.S. INTEC, or any other
person, has any authority to assume for U.S. INTEC any additional or other
liability or responsibility in connection with the roof described above. U.S.
INTEC shall not be responsible for or liable for any changes or amendment to
the U.S. INTEC roof specifications in regard  to the construction of the roof
described above, unless the change or amendment to the specifications is
approved in writing by an authorized U.S. INTEC Contractor Services Manager.

     This Guarantee is assignable to another owner of the building for the
remaining term ONLY if the following conditions are met: 1) The request is in
writing within 30 days after the ownership transfer; 2) The roof system and
building envelope and related system is inspected and any required repairs are
completed at the Owner's expense; 3) The proposed assignment is approved in
writing by an authorized U.S. INTEC Contractor Services Manager; and 4) An
assigned fee of $500 is paid to U.S. INTEC. This Guarantee is not otherwise
assignable directly or indirectly.

     CANCELLATION OF THIS GUARANTEE (1) WILL RESULT IF THE ROOF IS DAMAGED
BY ANY CAUSE LISTED ABOVE UNDER "EXCLUSIONS FROM COVERAGE" IF THE DAMAGE
AFFECTS THE INTEGRITY OR WATERTIGHTNESS OF THE ROOF, AND (2) THE OWNER DOES
NOT PROMPTLY MAKE REPAIRS FOLLOWING WRITTEN NOTIFICATION BY U.S. INTEC TO
RECTIFY THE DAMAGE AND PRESERVE THE INTEGRITY OF THE ROOF.

     THIS GUARANTEE IS EXPRESSLY IN LIEU OF ANY OTHER GUARANTEES AND/OR
WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, AND OF ANY OTHER
OBLIGATIONS OR LIABILITY ON THE PART OF U.S. INTEC, WHETHER ANY CLAIM AGAINST
IT IS BASED UPON STRICT LIABILITY, NEGLIGENCE, BREACH OF WARRANTY OR ANY
OTHER THEORY OR CAUSE OF ACTION. IN NO EVENT SHALL U.S. INTEC BE LIABLE FOR
ANY CONSEQUENTIAL OR INCIDENTAL DAMAGES OF ANY KIND.

NOTE: THIS GUARANTEE BECOMES EFFECTIVE ONLY WHEN BILLS FOR INSTALLATION AND
SUPPLIES HAVE BEEN PAID IN FULL TO THE ROOFING CONTRACTOR AND MATERIALS
SUPPLIERS, AND THE GUARANTEE CHARGE HAS BEEN PAID TO U.S. INTEC.

U.S. INTEC, INC.
1361 ALPS ROAD
WAYNE, NJ 07470

By: /s/ [ILLEGIBLE]
   ----------------------------
   Authorized Signature

Date  August 16, 2000

USICS100 5/00

<PAGE>

                                                      No.     WFGL 10-2768
                                                         -----------------------

                                                               LIBERTY GUARANTEE
   [LOGO]     ==================================================================
GAF MATERIALS
 CORPORATION

TYPE OF GUARANTEE:      GAFGLAS LIBERTY     PERIOD OF COVERAGE:  1O YEAR   YEARS
                  --------------------------                   ------------

OWNER:
      --------------------------------------------------------------------------

NAME AND TYPE OF BUILDING:    LOT
                          ------------------------------------------------------

ADDRESS OF BUILDING:
                    ------------------------------------------------------------

SPECIFICATION:                                   AREA OF ROOF:           SQUARES
              -----------------------------------             -----------

TYPE OF FLASHING:                          LENGTH OF FLASHING:       LINEAL FEET
                 --------------------------                   -------

APPLIED BY:         SUPERIOR ROOFING
           ---------------------------------------------------------------------

DATE OF COMPLETION:                                    EXPIRATION DATE:
                   ------------------------------------                ---------

THE GUARANTEE

     GAF MATERIALS CORPORATION ("GAFMC") guarantees to the Building Owner
that, subject to the terms and conditions set forth below, GAFMC will make
those repairs to the GAFMC roofing membrane, base flashing, insulation,
expansion joint covers and pre-flashed accessories (the "GAFMC Roofing
Materials") used in the construction of the above described roof as are
necessary to correct leaks while this Guarantee is in effect. This Guarantee
covers such repairs to the GAFMC Roofing Materials (excluding repair or
replacement of roof deck, insulation, or other materials used in conjunction
with the roofing system not sold by GAFMC) as shall be necessary solely in
order to correct leaks resulting from any of the causes listed below. These
repairs will be made at no cost to the Building Owner provided that the Owner
gives timely written notice to GAFMC (see below).

SCOPE OF COVERAGE - LEAKS CAUSED BY:

1. Natural deterioration of the GAFMC Roofing Materials
2. Blisters
3. Bare Spots
4. Fish-mouths
5. Ridges
6. Splits not caused by structural failure or movement of or cracks in
   substrate roof base or non-GAFMC insulation over which the GAFMC Roofing
   Materials are applied
7. Buckles and wrinkles
8. Workmanship in applying the GAFMC Roofing Materials
9.  Slippage of membrane or base flashing

OWNER'S RESPONSIBILITIES

     In the event of a leak through the GAFMC Roofing Materials, the Owner
must notify the GAFMC Technical Services Department, 1381 Alps Road, Bldg.
2-1, Wayne, New Jersey 07470 in writing within thirty days after discovery of
the leak. The roofing contractor is NOT an agent of GAFMC; notice to the
roofing contractor is NOT notice to GAFMC.

      The Owner shall, at its expense, (a) perform regular inspections and
maintenance during this Guarantee, (b) keep records of all inspections and
maintenance performed, and (c) perform repairs to the roof or to other
building components identified during inspections by GAFMC as being necessary
to preserve the integrity of the GAFMC Roofing Materials. Failure of the
Owner to perform this work promptly following written notification by GAFMC
may result in cancellation of this guarantee if the Owner's failure results
in damage to the GAFMC Roofing Materials.

     The Owner shall, at its expense, remove (and, if desired, subsequently
replace) any materials and equipment that impede inspection and repair of the
GAFMC Roofing Materials, such as HVAC units and satellite dishes mounted so
that there is no functional access to the roof system, and precast concrete
or rubber pavers, wood decking and steel grating that are installed over the
GAFMC Roofing Materials.

     In an emergency, the Owner may authorize or perform temporary repairs to
minimize damage to the building or its contents. Such work will not result in
the cancellation of this Guarantee provided that the temporary repairs are
reasonable and customary, and do not result in permanent damage to the GAFMC
Roofing Materials. The Owner is responsible for all expenses associated with
temporary repairs.

EXCLUSIONS FROM COVERAGE
This Guarantee shall NOT cover the following conditions or any damages which
may arise therefrom.

1. Roof maintenance or correction of conditions other than leaks.
2. Unusual weather conditions or natural disasters including, but not limited
   to, windstorms, hail, floods, hurricanes, lightning, tornados, and
   earthquakes.
3. Damage to the roof constructed of the GAFMC Roofing Materials due to:
   (a) settlement, distortion, movement, failure or cracking of the roof deck,
   walls, or foundations of the building; (b) improper installation of non-GAFMC
   insulation or defects or failure of any material used in any roof base or
   insulation not manufactured by GAFMC over which the GAFMC Roofing Materials
   are applied; (c) infiltration or condensation of moisture in, through or
   around the walls, copings, building structure, or underlying or surrounding
   materials including tie-ins to adjacent roof systems; (d) defects in design;
   (e) the performance, design, or application of non-GAFMC materials such as
   roof decks, metal work, expansion and control joints, pitch pockets,
   walkways, work platforms and recreational surfacings; (f) expansion or
   contraction of any metal flashing or other metal work; (g) underlying
   materials or structures having failed or ceased to conform to GAFMC's or
   other applicable specifications as to roof slopes or other requirements;
   (h) chemical attack on the membrane; (i) vandalism; or (j) negligence by the
   Owner in maintaining the GAFMC Roofing Materials.
4. Damage to the building or its contents.
5. Changes in usage of the building unless approved in writing in advance by
   GAFMC.
6. Damage resulting from any new installations on or through the GAFMC
   Roofing Materials or from traffic of any nature on the roof.
7. Temporary repairs to the GAFMC Roofing Materials authorized by the Owner.
8. Any repairs or other applications to the GAFMC Roofing Materials after the
   date of completion, unless performed in a manner acceptable to and approved
   by GAFMC in writing in advance, NOTE: In no event shall new penetrations be
   covered under the terms of guarantee.
9. Any damage occurring more than thirty days after the discovery by the
   Owner or its agent of a leak, unless GAFMC is notified of such leak within
   thirty days of its discovery.
10. Areas of roof which pond water.

   No representative, employee, or agent of GAFMC, or any other person, has
any authority to assume for GAFMC any additional or other liability or
responsibility in connection with the roof described above. GAFMC shall not
be responsible for or liable for any change or amendment to the GAFMC roof
specifications in regard to the construction of the roof described above,
unless the change or amendment to the specifications is approved in writing
by an authorized GAFMC Technical Services Manager.

   This Guarantee is assignable to another owner of the building for the
remaining term ONLY if the following conditions are met: 1) The request is in
writing within 30 days after ownership transfer; 2) The membrane is inspected
and any required repairs are completed at Owner's expense; 3) The proposed
assignment is approved in writing by an authorized GAFMC Technical Services
Manager; and 4) An assignment fee of $500 is paid to GAFMC. This Guarantee is
NOT otherwise assignable, directly or indirectly.

   CANCELLATION OF THIS GUARANTEE WILL RESULT IF THE ROOF IS DAMAGED BY ANY
CAUSE LISTED ABOVE UNDER "EXCLUSIONS FROM COVERAGE" IF THE DAMAGE AFFECTS THE
INTEGRITY OR WATERTIGHTNESS OF THE ROOF, AND THE OWNER DOES NOT PROMPTLY MAKE
REPAIRS FOLLOWING WRITTEN NOTIFICATION BY GAFMC TO RECTIFY THE DAMAGE AND
PRESERVE THE INTEGRITY OF THE ROOF.

   THIS GUARANTEE IS EXPRESSLY IN LIEU OF ANY OTHER GUARANTEES AND/OR
WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, AND OF ANY OTHER
OBLIGATIONS OR LIABILITY ON THE PART OF GAF MATERIALS CORPORATION, WHETHER
ANY CLAIM AGAINST IT IS BASED UPON STRICT LIABILITY, NEGLIGENCE, BREACH OF
WARRANTY OR ANY OTHER THEORY OR CAUSE OF ACTION. IN NO EVENT SHALL GAF
MATERIALS CORPORATION BE LIABLE FOR ANY CONSEQUENTIAL OR INCIDENTAL DAMAGES
OF ANY KIND.

NOTE: This Guarantee becomes effective only when bills for installation and
supplies have been paid in full to the roofing contractor and materials
supplied, and the Guarantee charge has been paid to GAF Materials Corporation.

                                       GAF MATERIALS CORPORATION
                                       1361 ALPS ROAD
                                       WAYNE, NJ 07470

                                       By         /s/  [Illegible]
                                         ---------------------------------------
                                                  Authorized Signature
                                       Date    April 29, 1998

     Form 10446 11/96

<PAGE>

                                   [LOGO]

                              MAINTENANCE PROGRAM

THANK YOU for selecting a GAF Materials Corporation roofing system. Whether
your roof is GAFGLAS(R) built-up, a RUBEROID(R) modified bitumen, or a
CompositeRoof(TM) roof system, we have a mutual interest in ensuring that
your guaranteed roof system performs to its capabilities.

GAFMC is responsible for repairing your roofing system in the event of a
leak, as outlined in your guarantee.

As the Building Owner, you also have a responsibility, which is to provide
necessary maintenance of your GAFMC roofing system and related building
components. Failure to provide necessary maintenance may result in
deterioration of your guaranteed roofing system that could otherwise have
been avoided. Repair of such deterioration will not be covered by your GAFMC
guarantee. In certain instances, such deterioration may be so extensive that
the roofing system can no longer be repaired and maintained, resulting in the
cancellation of your guarantee in whole or in part.

In order to ensure that your GAFMC roofing system will continue to perform to
its fullest, and to avoid possible cancellation or limitation of your GAFMC
guarantee, the following 10-point maintenance program is strongly recommended.

1.  Maintain a file for all records relating to this roof, including the
    GAFMC guarantee, invoices, inspection reports, repair and maintenance
    bills, original construction drawings and specifications, etc. A Roof
    Record Log is provided as part of this form.
2.  Inspect the roof a minimum of twice a year, typically in the spring and
    fall. In much of the country, the spring inspection is best performed
    immediately following this end of winter weather, so that any damages from
    freeze-thaw cycles, ice and other cold weather conditions can be addressed
    prior to spring rains. The fall inspection is best performed just before
    the beginning of winter weather, with any deficiencies addressed prior to
    ice and snow build-up so that cold weather-related stresses will not
    aggravate damaged or weakened conditions. The most common locations for
    damage and distress are drainage points, penetrations, and perimeter
    flashings.
3.  Inspect the roof for damage after severe weather conditions, such as
    hailstorms, heavy rains, high winds, etc.
4.  Arrange for repairs necessary to address non-guaranteed conditions
    affecting the GAFMC roof system. These repairs must be promptly performed
    by a GAFMC Approved or Master Roofing Contractor. Repairs should utilize
    GAFMC materials and repair methods that are consistent with the type and
    quality of the guaranteed roof system. This will ensure that repairs
    performed will last as long as the rest of the roof system.
5.  Remove any debris, such as leaves, branches, dirt, rocks, bottles, etc.
    that have accumulated on the roof. Clean gutters, downspouts, drains,
    scuppers, and the surrounding roof areas to ensure proper drainage.
6.  Examine all metal flashings, counterflashings, expansion joints, and
    pitch pockets for rust, detachment, deteriorated sealant, and damage.
    Reattach loose metalwork. Replace sealant as necessary. Prepare and paint
    any rusted metal.
7.  Examine masonry walls and copings for cracks, bad mortar joints,
    deteriorated sealant, loose masonry/coping stones, and indications of
    water absorption. Repair all such conditions to prevent water infiltration.
8.  Examine rooftop equipment such as air conditioners, ductwork, gooseneck
    vents, powered ventilator, evaporative coolers, antennas, equipment
    screens, skylights, satellite dishes, etc. for excessive movement, spillage
    of coolant, condensate, oil, grease, etc. and damage to sheet metal
    cabinets and rubber or fabric gaskets that may allow water infiltration.
    Keep all rooftop equipment in good condition.
9.  Examine protective coatings. Recoat any cracked, flaking, blistered or
    worn areas with compatible GAFMC coating.
10. Minimize rooftop traffic. Service personnel should take care to avoid
    dropping tools, equipment parts, etc. on the roof surface. Service
    personnel should not make any penetrations of or repairs to the roof
    system. All work affecting the GAFMC roof system must be performed by a
    GAFMC Approved or Master Roofing Contractor.

This maintenance program is intended to address conditions commonly found on
most buildings. Other conditions may exist that require special maintenance
considerations. It is the responsibility of the Building Owner to ensure that
the maintenance program followed for a particular building is adequate and
appropriate.

Any deficiencies in the GAFMC roof system noted during the performance of
periodic roof maintenance activities that are believed to be due to defects
in either the GAFMC roof materials or related installation workmanship should
be reported to the GAFMC Technical Services Department Bldg. 2-1, 1361 Alps
Road, Wayne, New Jersey 07470 within 30 days for possible guarantee coverage.

                              ROOF RECORD LOG
<TABLE>
<CAPTION>
YEAR    PURPOSE OF INSPECTION      DATE         NAME OF INSPECTOR             OUTCOME OF INSPECTION
<S>     <C>                      <C>           <C>                           <C>
1       Spring inspection         __/__/__      ______________________        _____________________________________
        Fall inspection           __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________

2       Spring inspection         __/__/__      ______________________        _____________________________________
        Fall inspection           __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________

3       Spring inspection         __/__/__      ______________________        _____________________________________
        Fall inspection           __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________

4       Spring inspection         __/__/__      ______________________        _____________________________________
        Fall inspection           __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________

5       Spring inspection         __/__/__      ______________________        _____________________________________
        Fall inspection           __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________
        Other                     __/__/__      ______________________        _____________________________________

</TABLE>

<PAGE>

                                   EXHIBIT D

                         APPROVED HAZARDOUS SUBSTANCES

- Cancer
- Acrylamide
- Cacodylic Acid
- Cadmium Chloride
- Chloramphenical
- Chloroform
- Cobalt Chloride
- Dichloromethane
- 1,4 Dioxane
- Formaldehyde
- Methyl Methanesulfonate
- Nickel Chloride
- Nickel Sulfate
- Radionuclides (phosphorus 32, phosphorous 33, Sulfur 35, and Hydrogen 3)
- Reproductive Toxicity
- Cadmium Chloride
- Cycloheximide
- Fluorouracil
- Penicillamine
- Streptomycin Sulfate
- Toluene

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00021-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00021-of-00352.parquet"}]]