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                                                                   Exhibit 10.20

                  AMERICAN INDUSTRIAL REAL ESTATE ASSOCIATION

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

1.  Basic Provisions ("Basic Provisions")

    1.1  Parties: This Lease ("Lease"), dated for reference purposes only
November 19, 1999, is made by and between American Advantech Corporation, a
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California corporation ("Lessor")
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and Somnus Medical Technologies, Inc., a Delaware corporation ("Lessee"),
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(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 as 750 East Arques Avenue, City of Sunnyvale
                  -------------------------------------------------------------
located in the County of Santa Clara,            State of California
                         ------------            -------------------
and generally described as (describe briefly the nature of the property and, if
applicable, the "Project", if the property is located within a Project)  A
                                                                        -------
free-standing office/light industrial building containing approximately 20,000
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square feet, together with a paved parking lot and landscaped grounds.
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("Premises"). (See also Paragraph 2)
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     1.3  Term:    Two            years and  one  months ("Original Term")
                -----------------           -----
commencing March 1, 2000 ("Commencement Date") and ending February 28, 2002
           -------------                                  -----------------
("Expiration Date"). (See also Paragraph 3)

     1.4  Early Possession:     See Addendum A      ("Early Possession Date").
                            -----------------------
(See also Paragraphs 3.2 and 3.3)

     1.5  Base Rent: $  See Addendum A      per month ("Base Rent"), payable on
                      ---------------------
the first             day of each month commencing   March 1, 2000
    -----------------                              ----------------------------
(See also Paragraph 4)
[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: $ 36,266.00
                                          -------------------------------------
as Base Rent for the period  January 25 through February 28, 2000
                            ---------------------------------------------------

     1.7  Security Deposit: $ 33,000.00 ("Security Deposit").
                            -----------
(See also Paragraph 5)

     1.8  Agreed Use:   General Office, training, storage, manufacturing and
                      ---------------------------------------------------------
production of medical devices and other legally permitted uses.
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(See also Paragraph 6)

     1.9  Insuring Party: Lessor is the "Insuring Party" unless otherwise stated
herein. (See also Paragraph 8)

     1.10  Real Estate Brokers: (See also Paragraph 15)
           (a) Representation: The following real estate brokers (collectively,
the "Brokers") and brokerage relationships exist in this transaction (check
applicable boxes):
[x] Cushman & Wakefield   represents Lessor exclusively ("Lessor's Broker");
    ---------------------           ("Lessor's Broker");
[x] Staubach Company      represents Lessee exclusively ("Lessee's Broker"); or
    ---------------------         ("Lessee's Broker"); or
[ ]                       represents both Lessor and Lessee ("Dual Agency").
    ---------------------
           (b) Payment to Brokers: Upon execution and delivery of this Lease by
both Parties, Lessor shall pay to the Broker the fee agreed to in their separate
written agreement (or if there is no such agreement, the sum of 5.5% of the
                                                                ----
total Base Rent for the brokerage services rendered by said Broker).

     1.11  Guarantor. The obligations of the Lessee under this Lease are to be
guaranteed by N/A ("Guarantor"). (See also Paragraph 37)
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     1.12  Addenda and Exhibits. Attached hereto is an Addendum or Addenda
consisting of Paragraphs   50   through   64   and Exhibits   1,
                         ------         ------              -----
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 size set forth in this Lease, or that may have been
used in calculating rental, is an approximation which the Parties agree is
reasonable and the rental based thereon is not subject to revision whether or
not the actual size is more or less.

     2.2  Condition. Lessor shall deliver the Premises to Lessee broom clean and
free of debris on the Commencement Date or the Early Possession Date, whichever
first occurs ("Start Date"), and, so long as the required service contracts
described in Paragraph 7.1(b) below are obtained by Lessee within thirty (30)
days following the Start Date, warrants that the existing electrical, plumbing,
fire sprinkler, lighting, heating, ventilating and air conditioning systems
("HVAC"), loading doors, if any, and all other such elements in the Premises,
other than those constructed by Lessee, shall be in good operating condition on
said date and that the structural elements of the roof, bearing walls and
foundation of any buildings on the Premises (the "Building") shall be free of
material defects. If a non-compliance with said warranty exists as of the Start
Date, Lessor shall, as Lessors sole obligation with respect to such matter,
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, after the Start Date,
Lessee does not give Lessor written notice of any non-compliance with this
warranty within: (i) one year as to the surface of the roof and the structural
portions of the roof, foundations and bearing walls, (ii) six (6) months as to
the HVAC systems, (iii) thirty (30) days as to the remaining systems and other
elements of the Building, correction of such non-compliance shall be the
obligation of Lessee at Lessee's sole cost and expense.

     2.3  Compliance. Lessor warrants that the improvements on the Premises
comply with all applicable laws, covenants or restrictions of record, building
codes, regulations and ordinances ("Applicable Requirements") in effect on the
Start 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. NOTE: Lessee is responsible for
determining whether or not the zoning is appropriate for Lessee's intended use,
and acknowledges that past uses of the Premises may no longer be allowed. If the
Premises do not comply with said warranty, Lessor shall, except as otherwise
provided, 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. If Lessee does not give Lessor written notice of a non-
compliance with this warranty within six (6) months following the Start Date,
correction of that non-compliance shall be the obligation of Lessee at Lessee's
sole cost and expense. If the Applicable Requirements are hereafter changed (as
opposed to being in existence at the Start Date, which is addressed in Paragraph
6.2 (e) below) so as to require during the term of this Lease the construction
of an addition to or an alteration of the Building, the remediation of any
Hazardous Substance, or the reinforcement or other physical modification of the
Building ("Capital Expenditure"), Lessor and Lessee shall allocate the cost of
such work as follows:

                                    PAGE 1                   Initials  /s/
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1997 - American Industrial real Estate Association
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          (a) Subject to Paragraph 2.3(c) below, if such Capital Expenditures
are required as a result of the specific and unique use of the Premises by
Lessee as compared with uses by tenants in general, Lessee shall be fully
responsible for the cost thereof, provided, however that if such Capital
Expenditure is required during the last two (2) years of this Lease and the cost
thereof exceeds three (3) months' Base Rent, Lessee may instead terminate this
Lease unless Lessor notifies Lessee, in writing, within ten (10) days after
receipt of Lessee's termination notice that Lessor has elected to pay the
difference between the actual cost thereof and the amount equal to three (3)
months' Base Rent. If Lessee elects termination, Lessee shall immediately cease
the use of the Premises which requires such Capital Expenditure and deliver to
Lessor written notice specifying a termination date at least ninety (90) days
thereafter. Such termination date shall, however, in no event be earlier than
the last day that Lessee could legally utilize the Premises without commencing
such Capital Expenditure.

          (b) If such Capital Expenditure is not the result of the specific and
unique use of the Premises by Lessee (such as, governmentally mandated seismic
modifications), then Lessor and Lessee shall allocate the obligation to pay for
such costs pursuant to the provisions of Paragraph 7.1(c); provided, however,
that if such Capital Expenditure is required during the last two years of this
Lease or if Lessor reasonably determines that it is not economically feasible to
pay its share thereof, Lessor shall have the option to terminate this Lease upon
ninety (90) days prior written notice to Lessee unless Lessee notifies Lessor,
in writing, within ten (10) days after receipt of Lessor's termination notice
that Lessee will pay for such Capital Expenditure. If Lessor does not elect to
terminate, and fails to tender its share of any such Capital Expenditure, Lessee
may advance such funds and deduct same, with interest, from Rent until Lessor's
share of such costs have been fully paid. If Lessee elects not to finance
Lessor's share, or if the balance of the Rent due and payable for the remainder
of this Lease is not sufficient to fully reimburse Lessee on an offset basis,
Lessee shall have the right to terminate this Lease upon thirty (30) days
written notice to Lessor.

          (c) Notwithstanding the above, the provisions concerning Capital
Expenditures are intended to apply only to non-voluntary, unexpected, and new
Applicable Requirements. If the Capital Expenditures are instead triggered by
Lessee as a result of an actual or proposed change in use, change in intensity
of use, or modification to the Premises then, and in that event, Lessee shall be
fully responsible for the cost thereof, and Lessee shall not have any right to
terminate this Lease.

     2.4  Acknowledgements. Lessee acknowledges that: (a) it has been advised by
Lessor and/or Brokers to satisfy itself with respect to the condition of the
Premises (including but not limited to the electrical, HVAC and fire sprinkler
systems, security, environmental aspects, and compliance with Applicable
Requirements), and their suitability for Lessee's intended use, (b) Lessee has
made such investigation as it deems necessary with reference to such matters and
assumes all responsibility therefor as the same relate to its occupancy of the
Premises, and (c) neither Lessor, Lessor's agent, nor any Broker has made any
oral or written representations or warranties with respect to said matters other
than as set forth in this Lease. In addition, Lessor acknowledges that: (a)
Broker has made no representations, promises or warranties concerning Lessee's
ability to honor the Lease or suitability to occupy the Premises, and (b) it is
Lessor's sole responsibility to investigate the financial capability and/or
suitability of all proposed tenants.

     2.5  Lessee as Prior Owner/Occupant. The warranties made by Lessor in
Paragraph 2 shall be of no force or effect if immediately prior to the Start
Date Lessee was the owner or occupant of the Premises. In such event, Lessee
shall be responsible for any necessary corrective work.

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
(including but not limited to the obligations to pay Real Property Taxes and
insurance premiums and to maintain the Premises) shall, however, be in effect
during such period. Any such early possession shall not affect the Expiration
Date.

     3.3  Delay In Possession. Lessor agrees to use its best commercially
reasonable efforts to deliver possession of the Premises to Lessee by the
Commencement Date. If, despite said efforts, Lessor is unable to deliver
possession as agreed, Lessor shall not be subject to any liability therefor, nor
shall such failure affect the validity of this Lease. Lessee shall not, however,
be obligated to pay Rent or perform its other obligations until it receives
possession of the Premises. If possession is not delivered within sixty (60)
days after the Commencement Date, Lessee may, at its option, by notice in
writing within ten (10) days after the end of such sixty (60) day period, cancel
this Lease, in which event the Parties shall be discharged from all obligations
hereunder. If such written notice is not received by Lessor within said ten (10)
day period, Lessee's right to cancel shall terminate. Except as otherwise
provided, if possession is not tendered to Lessee by the Start Date and Lessee
does not terminate this Lease, as aforesaid, any period of rent abatement 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
or omissions of Lessee. If possession of the Premises is not delivered within
four (4) months after the Commencement Date, this Lease shall terminate unless
other agreements are reached between Lessor and Lessee, in writing.

     3.4  Lessee Compliance. Lessor shall not be required to tender possession
of the Premises to Lessee until Lessee complies with its obligation to provide
evidence of insurance (Paragraph 8.5). Pending delivery of such evidence, Lessee
shall be required to perform all of its obligations under this Lease from and
after the Start Date, including the payment of Rent, notwithstanding Lessor's
election to withhold possession pending receipt of such evidence of insurance.
Further, if Lessee is required to perform any other conditions prior to or
concurrent with the Start Date, the Start Date shall occur but Lessor may elect
to withhold possession until such conditions are satisfied.

4.   Rent.

     4.1  Rent Defined. All monetary obligations of Lessee to Lessor under the
terms of this Lease (except for the Security Deposit) are deemed to be rent
("Rent").

     4.2  Payment. Lessee shall cause payment of Rent to be received by Lessor
in lawful money of the United States, without offset or deduction (except as
specifically permitted in this Lease), on or before the day on which it is due.
Rent 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 said
month. Payment of Rent shall be made to Lessor at its address stated herein or
to such other persons or place as Lessor may from time to time designate in
writing. Acceptance of a payment which is less than the amount then due shall
not be a waiver of Lessor's rights to the balance of such Rent, regardless of
Lessor's endorsement of any check so stating.

5.   Security Deposit. Lessee shall deposit with Lessor upon execution
hereof the Security Deposit as security for Lessee's faithful performance of its
obligations under this Lease. If Lessee fails to pay Rent, or otherwise Defaults
under this Lease, 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, expense, loss or damage 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 ten (10) days after written
request therefor deposit monies with Lessor sufficient to restore said Security
Deposit to the full amount required by this Lease. If the Base Rent increases
during the term of this Lease, Lessee shall, upon written request from Lessor,
deposit additional monies with Lessor so that the total amount of the Security
Deposit shall at all times bear the same proportion to the increased Base Rent
as the initial Security Deposit bore to the initial Base Rent. Should the Agreed
Use be amended to accommodate a material change in the business of Lessee or to
accommodate a sublessee or assignee, Lessor shall have the right to increase the
Security Deposit to the extent necessary, in Lessors reasonable judgment, to
account for any increased wear and tear that the Premises may suffer as a result
thereof. If a change of control of Lessee occurs during this Lease and following
such change the financial condition of Lessee is, in Lessor's reasonable
judgement, significantly reduced, Lessee shall deposit such additional monies
with Lessor as shall be sufficient to cause the Security Deposit to be at a
commercially reasonable level based on said change in financial condition.
Lessor shall not be required to keep the Security Deposit separate from its
general accounts. Within fourteen (14) days after the expiration or termination
of this Lease, if Lessor elects to apply the Security Deposit only to unpaid
Rent, and otherwise within thirty (30) days after the Premises have been vacated
pursuant to Paragraph 7.4(c) below, Lessor shall return that portion of the
Security Deposit not used or applied by Lessor. No part of the Security Deposit
shall be considered to be held in trust, to bear interest or to be prepayment
for any monies to be paid by Lessee under this Lease.

                                    PAGE 2             Initials /s/ (illegible)
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6.   Use.

     6.1  Use. Lessee shall use and occupy the Premises only for the Agreed Use,
or any other legal use which is reasonably comparable thereto, and for no other
purpose. Lessee shall not use or permit the use of the Premises in a manner that
is unlawful, creates damage, waste or a nuisance, or that disturbs owners and/or
occupants of, or causes damage to neighboring properties. Lessor shall not
unreasonably withhold or delay its consent to any written request for a
modification of the Agreed Use, so long as the same will not impair the
structural integrity of the improvements on the Premises or the mechanical or
electrical systems therein, is not significantly more burdensome to the
Premises. If Lessor elects to withhold consent, Lessor shall within five (5)
business days after such request give written notification of same, which notice
shall include an explanation of Lessor's objections to the change in use.

     6.2  Hazardous Substances.

          (a) Reportable Uses Require Consent. The term "Hazardous Substance" as
used in this Lease shall mean any product, substance, or waste whose presence,
use, manufacture, disposal, transportation, or release, either by itself or in
combination with other materials expected to be on the Premises, is either: (i)
potentially injurious to the public health, safety or welfare, the environment
or the Premises, (ii) regulated or monitored by any governmental authority, or
(iii) a basis for potential liability of Lessor to any governmental agency or
third party under any applicable statute or common law theory. Hazardous
Substances shall include, but not be limited to, hydrocarbons, petroleum,
gasoline, and/or crude oil or any products, by-products or fractions thereof.
Lessee shall not engage in any activity in or on the Premises which constitutes
a Reportable Use of Hazardous Substances without the express prior written
consent of Lessor and timely compliance (at Lessee's expense) with all
Applicable Requirements. "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, and/or
(iii) the presence at the Premises of a Hazardous Substance with respect to
which any Applicable Requirements requires that a notice be given to persons
entering or occupying the Premises or neighboring properties. Notwithstanding
the foregoing, Lessee may use any ordinary and customary materials reasonably
required to be used in the normal course of the Agreed Use, so long as such use
is in compliance with all Applicable Requirements, is not a Reportable Use, and
does not expose the Premises or neighboring property to any meaningful risk of
contamination or damage or expose Lessor to any liability therefor. In addition,
Lessor may condition its consent to any Reportable Use upon receiving such
additional assurances as Lessor reasonably deems necessary to protect itself,
the public, the Premises and/or the environment against damage, contamination,
injury and/or liability, including, but not limited to, the installation (and
removal on or before Lease expiration or termination) of protective
modifications (such as concrete encasements) and/or increasing the Security
Deposit.

          (b) Duty to Inform Lessor. If Lessee knows, or has reasonable cause to
believe, that a Hazardous Substance 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, and provide Lessor
with a copy of any report, notice, claim or other documentation which it has
concerning the presence of such Hazardous Substance.

          (c) Lessee Remediation. 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 or neighboring properties, that was caused or materially contributed to
by Lessee, or pertaining to or involving any Hazardous Substance brought onto
the Premises during the term of this Lease, by or for Lessee, or any third
party.

          (d) Lessee Indemnification. Lessee shall indemnify, defend and hold
Lessor, its agents, employees, lenders and ground lessor, if any, harmless from
and against any and all loss of rents and/or damages, liabilities, judgments,
claims, expenses, penalties, and attorneys' and consultants' fees arising out of
or involving any Hazardous Substance brought onto the Premises by or for Lessee,
or any third party (provided, however, that Lessee shall have no liability under
this Lease with respect to underground migration of any Hazardous Substance
under the Premises from adjacent properties). Lessee's obligations 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, removal, remediation, restoration and/or abatement, and shall
survive the expiration or 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, unless specifically so agreed by Lessor in writing at the time of
such agreement.

          (e) Lessor Indemnification. Lessor and its successors and assigns
shall indemnify, defend, reimburse and hold Lessee, its employees and lenders,
harmless from and against any and all environmental damages, including the cost
of remediation, which existed as a result of Hazardous Substances on the
Premises prior to the Start Date or which are caused by the gross negligence or
willful misconduct of Lessor, its agents or employees. Lessor's obligations, as
and when required by the Applicable Requirements, shall include, but not be
limited to, the cost of investigation, removal, remediation, restoration and/or
abatement, and shall survive the expiration or termination of this Lease.

          (f) Investigations and Remediations. Lessor shall retain the
responsibility and pay for any investigations or remediation measures required
by governmental entities having jurisdiction with respect to the existence of
Hazardous Substances on the Premises prior to the Start Date, unless such
remediation measure is required as a result of Lessee's use (including
"Alterations", as defined in Paragraph 7.3(a) below) of the Premises, in which
event Lessee shall be responsible for such payment. Lessee shall cooperate fully
in any such activities at the request of Lessor, including allowing Lessor and
Lessor's agents to have reasonable access to the Premises at reasonable times in
order to carry out Lessor's investigative and remedial responsibilities.

          (g) Lessor Termination Option. If a Hazardous Substance Condition
occurs during the term of this Lease, unless Lessee is legally responsible
therefor (in which case Lessee shall make the investigation and remediation
thereof required by the Applicable Requirements and this Lease shall continue in
full force and effect, but subject to Lessor's rights under Paragraph 6.2(d) and
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 Lessors expense, in which event this Lease shall continue in full
force and effect, or (ii) if the estimated cost to remediate such condition
exceeds twelve (12) times the then monthly Base Rent of $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 date of such notice. In the event Lessor elects to give a termination
notice, Lessee may, within ten (10) days thereafter, give written notice to
Lessor of Lessee's commitment to pay the amount by which the cost of the
remediation of such Hazardous Substance Condition exceeds an amount equal to
twelve (12) times the then monthly Base Rent or $100,000, whichever is greater.
Lessee shall provide Lessor with said funds or satisfactory assurance thereof
within thirty (30) days following such commitment. In such event, this Lease
shall continue in full force and effect, and Lessor shall proceed to make such
remediation as soon as reasonably possible after the required funds are
available. If Lessee does not give such notice and provide the required funds
or assurance thereof within the time provided, this Lease shall terminate as of
the date specified in Lessor's notice of termination.

     6.3  Lessee's Compliance with Applicable Requirements. Except as otherwise
provided in this Lease, Lessee shall, at Lessee's sole expense, fully,
diligently and in a timely manner, materially comply with all Applicable
Requirements, the requirements of any applicable fire insurance underwriter or
rating bureau, at the recommendations of Lessor's engineers and/or consultants
which relate in any manner to the Premises, without regard to whether said
requirements are now in effect or become effective after the Start Date. Lessee
shall, within ten (10) days after receipt of Lessor's written request, provide
Lessor with copies of all permits and other documents, and other information
evidencing Lessee's compliance with any Applicable Requirements 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 the failure of
Lessee or the Premises to comply with any Applicable Requirements.

     6.4  Inspection; Compliance. Lessor and Lessor's "Lender" (as defined in
Paragraph 30 below) and consultants shall have the right to enter into 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. The cost of any such inspections shall be
paid by Lessor, unless a material violation of Applicable Requirements, or a
contamination is found to exist or be imminent, or the inspection is requested
or ordered by a governmental authority. In such case, Lessee shall upon request
reimburse Lessor for the cost of such inspections, so long as such inspection is
reasonably related to the violation or contamination.

                                    PAGE 3                   Initials /s/
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<PAGE>

7. Maintenance; Repairs, Utility Installations; Trade Fixtures and Alterations.

   7.1  Lessee's Obligations.

          (a) In General. Subject to the provisions of Paragraph 2.2
(Condition), 2.3 (Compliance), 6.3 (Lessee's Compliance with Applicable
Requirements), 7.2 (Lessor's Obligations), 9 (Damage or Destruction), and 14
(Condemnation), Lessee shall, at Lessee's sole expense, keep the Premises,
Utility Installations, and Alterations in good order, condition and repair
(whether or not the portion of the Premises requiring repairs, or the means of
repairing the same, are reasonably or readily accessible to Lessee, and whether
or not the need for such repairs occurs as a result of Lessee's use, any prior
use, the elements or the age of such portion of the Premises), including, but
not limited to, all equipment or facilities, such as plumbing, heating,
ventilating, air-conditioning, electrical, lighting facilities, boilers,
pressure vessels, fire protection system, 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, or adjacent to the Premises. Lessee, in
keeping the Premises in good order, condition and repair, shall exercise and
perform good maintenance practices, specifically including the procurement and
maintenance of the service contracts required by Paragraph 7.1(b) below.
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. Lessee shall, during the term of this
Lease, keep the exterior appearance of the Building in a first-class condition
consistent with the exterior appearance of other similar facilities of
comparable age and size in the vicinity, including, when necessary, the exterior
repainting of the Building.

          (b) Service Contracts. Lessee shall, at Lessee's sole expense, procure
and maintain contracts, with copies to Lessor, in customary form and substance
for, and with contractors specializing and experienced in the maintenance of the
following equipment and improvements ("Basic Elements"), if any, if and when
installed on the Premises: (i) HVAC equipment, (ii) boiler and pressure vessels,
(iii) fire extinguishing systems, including fire alarm and/or smoke detection,
(iv) landscaping and irrigation systems, (v) roof covering and drains, (vi)
driveways and parking lots, (vii) clarifiers, (viii) basic utility and feed to
the perimeter of the Building, and (ix) any other equipment, if reasonably
required by Lessor.

          (c) Replacement. Subject to Lessee's indemnification of Lessor as set
forth in Paragraph 8.7 below, and without relieving Lessee of liability
resulting from Lessee's failure to exercise and perform good maintenance
practices, if the Basic Elements described in Paragraph 7.1(b) cannot be
repaired other than at a cost which is in excess of 50% of the cost of replacing
such Basic Elements, then such Basic Elements shall be replaced by Lessor, and
the cost thereof shall be prorated between the Parties and Lessee shall only be
obligated to pay, each month during the remainder of the term of this Lease, on
the date on which Base Rent is due, an amount equal to the product of
multiplying the cost of such replacement by a fraction, the numerator of which
is one, and the denominator of which is the number of months of the useful life
of such replacement as such useful life is specified pursuant to Federal income
tax regulations or guidelines for depreciation thereof (including interest on
the unamortized balance as is then commercially reasonable in the judgment of
Lessor's accountants), with Lessee reserving the right to prepay its obligation
at any time.

     7.2  Lessor's Obligations. Subject to the provisions of Paragraphs 2.2
(Condition), 2.3 (Compliance), 9 (Damage or Destruction) and 14 (Condemnation),
it is intended by the Parties hereto that Lessor have no obligation, in any
manner whatsoever, to repair and maintain the Premises, or the equipment
therein, all of which obligations are intended to be that of the Lessee. 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, and
they expressly waive the benefit of any statute now or hereafter in effect to
the extent it is inconsistent with the terms of this Lease.

     7.3  Utility Installations; Trade Fixtures; Alterations.

          (a) Definitions; Consent Required. The term "Utility Installations"
refers to all floor and window coverings, air lines, power panels, electrical
distribution, security and fire protection systems, communication systems,
lighting fixtures, HVAC equipment, plumbing, and fencing in or on 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, 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 pursuant
to Paragraph 7.4(a). Lessee shall not make any Alterations or Utility
Installations to 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) without such consent but upon notice to Lessor, 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 this Lease as extended does not exceed $50,000 in the aggregate
or $10,000 in any one year.

          (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 detailed plans. Consent shall be deemed
conditioned upon Lessee's: (i) acquiring all applicable governmental permits,
(ii) furnishing Lessor with copies of both the permits and the plans and
specifications prior to commencement of the work, and (iii) compliance with all
conditions of said permits and other Applicable Requirements in a prompt and
expeditious manner. Any Alterations or Utility Installations shall be performed
in a workmanlike manner with good and sufficient materials. Lessee shall
promptly upon completion furnish Lessor with as-built plans and specifications.
For work which costs an amount equal to the greater of one month's Base Rent or
$10,000, Lessor may condition its consent upon Lessee providing 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.

          (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 mechanic's 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. If Lessee shall 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. If Lessor shall require, Lessee shall furnish a surety bond 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. If Lessor elects
to participate in any such action, Lessee shall pay Lessor's attorneys' fees and
costs.

     7.4  Ownership; Removal; Surrender; and Restoration.

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

          (b) Removal. By delivery to Lessee of written notice from Lessor not
earlier than ninety (90) and not later than thirty (30) days prior to the end of
the term of this Lease, Lessor may require that any or all Lessee Owned
Alterations or Utility Installations be removed by the expiration or termination
of this Lease. 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.

          (c) Surrender/Restoration. Lessee shall surrender the Premises by the
Expiration Date or any earlier termination date, with all of the improvements,
parts and surfaces thereof broom 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. Lessee shall repair any damage
occasioned by the installation, maintenance or removal of Trade Fixtures, Lessee
Owned Alterations and/or Utility Installations, furnishings, and equipment 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 groundwater
contaminated by Lessee. Trade Fixtures shall remain the property of Lessee and
shall be removed by Lessee. The failure by Lessee to timely vacate the Premises
pursuant to this Paragraph 7.4(c) without the express written consent of Lessor
shall constitute a holdover under the provisions of Paragraph 26 below.

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8.   Insurance; Indemnity.

     8.1  Payment For Insurance. Lessee shall pay for all insurance required
under Paragraph 8 except to the extent of the cost attributable to liability
insurance carried by Lessor under Paragraph 8.2(b) in excess of $2,000,000 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.

     8.2  Liability Insurance.

          (a) Carried by Lessee. Lessee shall obtain and keep in force a
Commercial General Liability Policy of Insurance protecting Lessee and Lessor
against claims for bodily injury, personal injury and property damage based upon
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 $2,000,000 per
occurrence with an "Additional Insured-Managers or Lessors of Premises
Endorsement" and contain the "Amendment of the Pollution Exclusion Endorsement"
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 shall not, however, limit the
liability of Lessee nor relieve Lessee of any obligation hereunder. All
insurance 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. Lessor shall maintain liability insurance as
described in Paragraph 8.2(a), 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 a policy or policies in the name of Lessor, with loss payable to
Lessor, any groundlessor, and to any Lender(s) insuring loss 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 any Lenders, but in no event more than the commercially reasonable
and available insurable value thereof. If Lessor is the Insuring Party, however,
Lessee Owned Alterations and Utility Installations Trade Fixtures, and Lessee's
personal property 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 debris removal and the enforcement of any Applicable
Requirements requiring the upgrading, demolition, reconstruction or replacement
of any portion of the Premises as the result of a covered 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.

          (b) Rental Value. The Insuring Party shall obtain and keep in force a
policy or policies in the name of Lessor with loss payable to Lessor and any
Lender, insuring the loss of the full Rent for one (1) year. Said insurance
shall provide that in the event the Lease is terminated by reason of an insured
loss, the period of indeminity for such coverage shall be extended beyond the
date of the completion of repairs of replacement of the Premises, to provide for
one full year's loss of Rent from the date of any such loss. Said insurance
shall contain an agreed valuation provision in lieu of any coinsurance clause,
and the amount of coverage shall be adjusted annually to refelct the projected
Rent 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 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.

     8.4  Lessee's Property/Business Interruption Insurance.

          (a) Property Damage. Lessee shall obtain and maintain insurance
coverage on all of Lessee's personal property, Trade Fixtures, and Lessee Owned
Alterations and Utility Installations. 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, Trade Fixtures and Lessee Owned Alterations and Utility
Installations. Lessee shall provide Lessor with written evidence that such
insurance is in force.

          (b) Business Interruption. Lessee shall obtain and maintain loss of
income and extra expense insurance in amounts as will reimburse Lessee for
direct or indirect loss of earnings attributable to all perils commonly insured
against by prudent lessees in the business of Lessee or attributable to
prevention of access to the Premises as a result of such perils.

          (c) No Representation of Adequate Coverage. Lessor makes no
representation that the limits or forms of coverage of insurance specified
herein are adequate to cover Lessee's property, business operations or
obligations under this Lease.

     8.5 Insurance Policies. Insurance required herein shall be by companies
duly licensed or admitted 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, as set forth in the most current issue of "Best's
Insurance Guide", or such other rating as may be required by a Lender. Lessee
shall not do or permit to be done anything which invalidates the required
insurance policies. Lessee shall, prior to the Start Date, deliver to Lessor
certified copies of policies of such insurance or certificates evidencing the
existence and amounts of the required insurance. No such policy shall be
cancelable 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. Such policies shall be for a term of at least
one year, or the length of the remaining term of this Lease, whichever is less.
If either Party shall fail to procure and maintain the insurance required to be
carried by it, the other Party may, but shall not be required to, procure and
maintain the same.

     8.6  Waiver of Subrogation. Without affecting any other rights or remedies,
Lessee and Lessor each hereby release and relieve the other, and waive their
entire right to recover damages against the other, for loss of or damage to its
property arising out of or incident to the perils required to be insured against
herein. The effect of such releases and waivers is not limited by the amount of
insurance carried or required, or by any deductibles applicable hereto. The
Parties agree to have their respective property damage insurance carriers waive
any right to subrogation that such companies may have against Lessor or Lessee,
as the case may be, so long as the insurance is not invalidated thereby.

     8.7  Indemnity. Except for Lessor's gross negligence or willful misconduct,
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, loss of rents and/or damages, liens, judgments,
penalties, attorneys' and consultants' fees, expenses and/or liabilities arising
out of, involving, or in connection with, the use and/or occupancy of the
Premises by Lessee. If any action or proceeding is brought against Lessor by
reason of any of the foregoing matters, Lessee shall upon notice 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 defended or indemnified.

     8.8 Exemption of Lessor from Liability. 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, HVAC or lighting fixtures, or from any other cause,
whether the said injury of 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. 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, which can reasonably be repaired in six (6) months or less from
the date of the damage or destruction.

                                    PAGE 5                   Initials /s/
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Lessor shall notify Lessee in writing within thirty (30) days from the date of
the damage or destruction as to whether or not the damage is Partial or Total.

          (b) "Premises Total Destruction" shall mean damage or destruction to
the Premises, other than Lessee Owned Alterations and Utility Installations and
Trade Fixtures, which cannot reasonably be repaired in six (6) months or less
from the date of the damage or destruction. Lessor shall notify Lessee in
writing within thirty (30) days from the date of the damage or destruction as to
whether or not the damage is Partial or Total.

          (c) "Insured Loss" shall mean damage or destruction to improvements on
the Premises, other than Lessee Owned Alterations and Utility Installations and
Trade Fixtures, 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 Requirements, 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 any
applicable 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, such shortage 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 such funds or assurance are not received, Lessor shall then elect by
written notice to Lessee within ten (10) days thereafter shall either: (i) 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, or (ii) have this Lease terminate thirty (30) days thereafter. Lessee
shall not be entitled to reimbursement of 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, 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.

     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),
Lessor may 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) terminate this Lease by giving written notice to Lessee within
thirty (30) days after receipt by Lessor of knowledge of the occurrence of such
damage. Such termination shall be effective sixty (60) days following the date
of such notice. In the event Lessor elects to terminate this Lease, Lessee shall
have the right within ten (10) days after receipt of the termination notice to
give written notice to Lessor of Lessee's commitment to pay for the repair of
such damage without reimbursement from Lessor, Lessee shall provide Lessor with
said funds or satisfactory assurance thereof within thirty (30) days after
making such 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 after the required funds are available. If Lessee does not make the
required commitment, this Lease shall terminate as of the date specified in the
termination notice.

     9.4  Total Destruction. Notwithstanding any other provision hereof, if a
Premises Total Destruction occurs, this Lease shall terminate sixty (60) days
following such Destruction. If the damage or destruction was caused by the gross
negligence or willful misconduct of Lessee, and is not an insured loss, Lessor
shall have the right to recover Lessor's damages from Lessee, except as provided
in Paragraph 8.6.

     9.5  Damage Near End of Term. If at any time during the last six (6) months
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 terminate this
Lease effective sixty (60) days following the date of occurrence of such damage
by giving a written termination notice to Lessee within thirty (30) days after
the date of occurrence of such damage. Notwithstanding the foregoing, 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, (a) exercising such option and
(b) providing Lessor with any shortage in insurance proceeds (or adequate
assurance thereof) needed to make the repairs on or before the earlier of (i)
the date which is ten days after Lessee's receipt of Lessor's written notice
purporting to terminate this Lease, or (ii) the day prior to the date upon which
such option expires. If Lessee duly exercises such option during such period and
provides Lessor with funds (or adequate assurance thereof) to cover any shortage
in insurance proceeds, Lessor shall, at Lessor's commercially reasonable
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 such period, then this Lease shall
terminate on the date specified in the termination notice and Lessee's option
shall be extinguished.

     9.6  Abatement of Rent; Lessee's Remedies.

          (a) Abatement. In the event of Premises Partial Damage or Premises
Total Destruction or a Hazardous Substance Condition for which Lessee is not
responsible under this Lease, the Rent payable by Lessee for the period required
for the repair, remediation or restoration of such damage shall be abated in
proportion to the degree to which Lessee's use of the Premises is impaired. All
other obligations of Lessee hereunder shall be performed by Lessee, and Lessor
shall have no liability for any such damage, destruction, remediation, repair or
restoration except as provided herein.

          (b) Remedies. If Lessor shall be obligated to repair or restore the
Premises and does not commence, in a substantial and meaningful way, such repair
or restoration 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
and such repair or restoration is not commenced within thirty (30) days
thereafter, this Lease shall terminate as of the date specified in said notice.
If the repair or restoration is commenced within said thirty (30) days, this
Lease shall continue in full force and effect. "Commence" 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  Termination - Advance Payments. Upon termination of this Lease
pursuant to Paragraph 6.2(g) or 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.

     9.8  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 Definition of "Real Property Taxes. "As used herein, the term "Real
Property Taxes" shall include any form of assessment; real estate, general,
special, ordinary or extraordinary, or rental levy or tax (other than
inheritance, personal income or estate taxes); improvement bond; and/or license
fee imposed upon or levied against any legal or equitable interest of Lessor in
the Premises, Lessor's right to other income therefrom, and/or Lessor's business
of leasing, by any authority having the direct or indirect power to tax and
where the funds are generated

                                    PAGE 6                   Initials /s/
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with reference to the Building address and where the proceeds so generated are
to be applied by the city, county or other local taxing authority of a
jurisdiction within which the Premises are located. 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 during the term of this
Lease, including but not limited to, a change in the ownership of the Premises.

     10.2

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

          (b) Advance Payment. In the event Lessee incurs a late charge on any
Rent payment, Lessor may, at Lessor's option, estimate the current Real Property
Taxes, and require that such taxes be paid in advance to Lessor by Lessee,
either: (i) in a lump sum amount equal to the installment due, al 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 an amount equal to the amount of the
estimated installment of taxes divided by the number of months remaining before
the month in which said installment becomes delinquent. When the actual amount
of the applicable tax bill is known, the amount of such equal monthly advance
payments shall be adjusted as required to provide the funds needed to pay the
applicable taxes. If the amount collected by Lessor is insufficient to pay such
Real Property Taxes when due, Lessee shall pay Lessor, upon demand, such
additional sums as are necessary to pay such obligations. All money paid to
Lessor under this Paragraph may be intermingled with other money of Lessor and
shall not bear interest. In the event of a Breach by Lessee in the performance
of its obligations under this Lease, then any balance of funds paid to Lessor
under the provisions of this Paragraph may at the option of Lessor, be treated
as an additional Security Deposit.

     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 conclusively determined by Lessor from the respective
valuations assigned in the assessor's work sheets or such other information as
may be reasonably available.

     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. When possible, Lessee shall cause such 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's property within ten (10) days
after receipt of a written statement.

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.

12.  Assignment and Subletting.

     12.1  Lessor's Consent Required.

           (a) Lessee shall not voluntarily or by operation of law assign,
transfer, mortgage or encumber (collectively, "assign or assignment") or sublet
all or any part of Lessee's interest in this Lease or in the Premises without
Lessor's prior written consent.

          (b) a change in the control of Lessee shall constitute an assignment
requiring 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,
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 by an amount greater than
twenty-five percent (25%) of such Net Worth as it was represented at the time of
the execution 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, whichever was or is
greater, shall be considered an assignment of this Lease to which Lessor may
withhold its consent. "Net Worth of Lessee" shall mean the net worth of Lessee
(excluding any guarantors) established under generally accepted accounting
principles.

          (d) An assignment or subletting without 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 unapproved assignment or subletting as a noncurable Breach, Lessor
may either: (i) terminate this Lease, or (ii) upon thirty (30) days written
notice, increase the monthly Base Rent to one hundred ten percent (110%) of the
Base Rent then in effect. Further, in the event of such Breach and rental
adjustment, (i) the purchase price of any option to purchase the Premises held
by Lessee shall be subject to similar adjustment to one hundred ten percent
(110%) of the price previously in effect, and (ii) all fixed and non-fixed
rental adjustments scheduled during the remainder of the Lease term shall be
increased to One Hundred Ten Percent (110%) of the scheduled adjusted rent.

          (e) Lessee's remedy for any breach of Paragraph 12.1 by Lessor shall
be limited to compensatory damages and/or injunctive relief.

     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 Rent or for the performance of any other obligations to be
performed by Lessee.

          (b) Lessor may accept Rent or performance of Lessee'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 Rent or performance shall constitute a waiver of estoppel of
Lessor's right to exercise its remedies for Lessee's Default or Breach.

          (c) Lessor's consent to any assignment or subletting shall not
constitute a consent to any subsequent assignment or subletting.

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

          (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 fee of $1,000 as
consideration for Lessor's considering and processing said request. Lessee
agrees to provide Lessor with such other or additional information and/or
documentation as may be reasonably requested.

          (f) Any assignee of, or sublessee under, this Lease shall, by reason
of accepting such assignment or entering into such sublease, be deemed 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 to in writing.

     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 Rent payable on any sublease, and Lessor may collect such Rent
and apply same toward Lessee's obligations under this Lease; provided, however,
that until a Breach shall occur in the performance of Lessee's obligations,
Lessee may collect said Rent. Lessor shall not, by reason of the foregoing or
any assignment of such sublease, nor by reason of the collection of Rent, be
deemed liable to the sublessee for any failure of Lessee to perform and comply
with any of Lessee's obligations to such sublessee. Lessee hereby irrevocably
authorizes and directs any such sublessee, upon receipt of a written notice

                                    PAGE 7                   Initials /s/
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from Lessor stating that a Breach exists in the performance of Lessee's
obligations under this Lease, to pay to Lessor all Rent due and to become due
under the sublease. Sublessee shall rely upon any such notice from Lessor and
shall pay all Rents to Lessor without any obligation or right to inquire as to
whether such Breach exists, notwithstanding any claim from Lessee to the
contrary.

          (b) In the event of a Breach by Lessee, Lessor may, at its option,
require 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 prior Defaults or Breaches of such
sublessor.

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

          (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
comply with or perform any of the terms, covenants, conditions or rules under
this Lease. A "Breach" is defined as the occurrence of one or more of the
following Defaults, and the failure of Lessee to cure such Default within any
applicable grace period:

          (a) The abandonment of the Premises; or the vacating of the Premises
without providing a commercially reasonable level of security, or where the
coverage of the property insurance described in Paragraph 8.3 is jeopardized as
a result thereof, or without providing reasonable assurances to minimize
potential vandalism.

          (b) The failure of Lessee to make any payment of Rent or any Security
Deposit required to be made by Lessee hereunder, whether to Lessor, when due, to
provide reasonable evidence of insurance or surety bond, or to fulfill any
obligation under this Lease which endangers or threatens life or property, where
such failure continues for a period of three (3) business days following written
notice to Lessee.

          (c) The failure by Lessee to provide (i) reasonable written evidence
of compliance with Applicable Requirements, (ii) the service contracts, (iii)
the rescission of an unauthorized assignment or subletting, (iv) a Tenancy
Statement, (v) a requested subordination, (vi) evidence concerning any guaranty
and/or Guarantor, (vii) 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 ten (10) days following written notice 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,
other than those described in subparagraphs 13.1(a), (b) or (c), above, where
such Default continues for a period of thirty (30) days after written notice;
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 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 of
any general arrangement or assignment for the benefit of creditors; (ii)
becoming a "debtor" as defined in 11 U.S.C. (S) 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 13.1 (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 that any financial statement of Lessee or of any
Guarantor given to Lessor 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 basis, and
Lessee's failure, within sixty (60) days following written notice of any such
event, to provide written alternative assurance or security, which, when coupled
with the then existing resources of Lessee, equals or exceeds 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 of its affirmative duties or
obligations, within ten (10) days after written notice (or in case of an
emergency, without notice), Lessor may, at its option, 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 upon receipt of invoice therefor. If more than two (2)
checks 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 by
Lessee to be by cashier's check. In the event of a Breach, Lessor may, 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:

          (a) Terminate Lessee's right to possession of the Premises by any
lawful means, in which case this Lease shall terminate and Lessee shall
immediately surrender possession to Lessor. In such event Lessor shall be
entitled to recover from Lessee: (i) 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 reletting, including necessary
renovation and alteration of the Premises, reasonable attorneys' fees, and that
portion of any leasing commission paid by Lessor in connection with this Lease
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 immediately preceding
sentence shall be computed by discounting such amount at the discount rate of
the Federal Reserve Bank of the District within which the Premises are located
at the time of award plus one percent (1%). Efforts by Lessor to mitigate
damages caused by Lessee's Breach of this Lease shall not waive Lessors right to
recover damages under Paragraph 12. If termination of this Lease is obtained
through the provisional remedy of unlawful detainer, Lessor shall have the right
to recover in such proceeding any unpaid Rent and damages as are recoverable
therein, or Lessor may reserve the right to recover all or any part thereof in a
separate suit. If a notice and grace period required under Paragraph 13.1 was
not previously given, a notice to pay rent or quit, or to perform or quit given
to Lessee under the unlawful detainer statute shall also constitute the notice
required by Paragraph 13.1. In such case, the applicable grace period required
by Paragraph 13.1 and the unlawful detainer statute shall run concurrently, 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 and recover
the Rent as it becomes due, in which event Lessee may sublet or assign, subject
only to reasonable limitations. Acts of maintenance, efforts to relet, and/or
the appointment of a receiver to protect the Lessor's interests, shall not
constitute a termination of the Lessee's right to possession.

          (c) Pursue any other remedy now or hereafter available under the laws
or judicial decisions of the state wherein the Premises are located. The
expiration or termination of this Lease and/or the termination of Lessee's right
to possession shall not relieve Lessee from liability

                                    PAGE 8                   Initials /s/
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<PAGE>

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. Any agreement for free or abated rent or other
charges, 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 referrred 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. Upon
Breach of this Lease by Lessee, 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 uner such an Inducement Provision
shall be immediately due and payable by Lessee to Lessor, 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
of Rent 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 any Lender. Accordingly, if any Rent
shall not be received by Lessor within five (5) days after such amount shall be
due, then, without any requirement for notice to Lessee, Lessee shall pay to
Lessor a one-time late charge equal to seven percent (7%) of each 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 such late
payment. 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 the exercise of 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 any
provision of this Lease to the contrary, Base Rent shall, at Lessor's option,
become due and payable quarterly in advance.

     13.5  Interest. Any monetary payment due Lessor hereunder, other than late
charges, not received by Lessor, when due as to scheduled payments (such as Base
Rent) or within thirty (30) days following the date on which it was due for non-
scheduled payment, shall bear interest from the date when due, as to scheduled
payments, or the thirty-first (31st) day after it was due as to non-scheduled
payments. The interest ("Interest") charged shall be equal to the prime rate
reported in the Wall Street Journal as published closest prior to the date when
due plus four percent (4%), but shall not exceed the maximum rate allowed by
law. Interest is payable in addition to the potential late charge provided for
in Paragraph 13.4.

     13.6  Breach by Lessor.

           (a) Notice of Breach. Lessor shall not be deemed in breach of this
Lease unless Lessor fails within a reasonable time to perform any obligation
required to be performed by Lessor. For purposes of this Paragraph, a reasonable
time shall in no event be less than thirty (30) days after receipt by Lessor,
and any Lender 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 are reasonably
required for its performance, then Lessor shall not be in breach if performance
is commenced within such thirty (30) day period and thereafter diligently
pursued to completion.

           (b) Performance by Lessee on Behalf of Lessor. In the event that
neither Lessor nor Lender cures said breach within thirty (30) days after
receipt of said notice, or if having commenced said cure they do not diligently
pursue it to completion, then Lessee may elect to cure said breach at Lessee's
expense and offset from Rent an amount equal to the greater of one month's Base
Rent or the Security Deposit, and to pay an excess of such expense under
protest, reserving Lessee's right to reimbursement from Lessor. Lessee shall
document the cost of said cure and supply said documentation to Lessor.

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
(collectively "Condemnation"), this Lease shall terminate as to the part taken
as of the date the condemning authority takes title or possession, whichever
first occurs. If more than ten percent (10%) of any building portion of the
Premises, or more than twenty-five percent (25%) of the land area portion of the
Premises 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 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 proportion
to the reduction in utility of the Premises caused by such Condemnation. Lessee
shall be entitled to any compensation for value of leasehold, Lessee's
relocation expenses, loss of business goodwill and/or Trade Fixtures, without
regard to whether or not this Lease is terminated pursuant to the provisions of
this Paragraph. All Alterations and Utility Installations made to the Premises
by Lessee, for purposes of Condemnation only, shall be considered the property
of the Lessee and Lessee shall be entitled to any and all compensation which is
payable therefor. In the event that this Lease is not terminated by reason of
the Condemnation, Lessor shall repair any damage to the Premises caused by such
Condemnation.

15.  Brokers' Fee.

     15.1  Additional Commission. In addition to the payments owed pursuant to
Paragraph 1.10 above, and unless Lessor and the Brokers otherwise agree in
writing, Lessor agrees that: (a) if Lessee exercises any Option, (b) if Lessee
acquires any rights to the Premises or other premises owned by Lessor and
located within the same Project, if any, within which the Premises is located,
(c) if Lessee remains in possession of the Premises, with the consent of Lessor,
after the expiration of this Lease, or (d) if Base Rent is increased, whether by
agreement or operation of an escalation clause herein, then, Lessor shall pay
Brokers a fee in accordance with the schedule of said Brokers in effect at the
time of the execution of this Lease.

     15.2  Assumption of Obligations. Any buyer or transferee of Lessor's
interest in this Lease shall be deemed to have assumed Lessor's obligation
hereunder. Each Broker shall be a third party beneficiary of the provisions of
Paragraphs 1.10, 15, 22 and 31. If Lessor fails to pay to a Broker any amounts
due as and for commissions pertaining to this Lease when due, then such amounts
shall accrue interest. In addition, if Lessor fails to pay any amounts to
Lessee's Broker when due, Lessee's Broker may send written notice to Lessor and
Lessee of such failure and if Lessor fails to pay such amounts within ten (10)
days after said notice, Lessee shall pay said monies to its Broker and offset
such amounts against Rent. In addition, Lessee's Broker shall be deemed to be a
third party beneficiary of any commission agreement entered into by and/or
between Lessor and Lessor's Broker.

     15.3  Representations and Indemnities of Broker Relationships. 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) in
connection with this Lease, and that no one other than said named Brokers is
entitled to any commission or finder's fee in connection herewith. 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, and/or attorneys' fees reasonably incurred with respect thereto.

16.  Estoppel Certificates.

           (a) 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 "Estoppel Certificate" 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.

           (b) If the Responding Party shall fail to execute or deliver the
Estoppel Certificate within such ten day period, the Requesting Party may
execute an Estoppel Certificate stating that: (i) the Lease is in full force and
effect without modification except as may be represented by the Requesting
Party, (ii) there are no uncured defaults in the Requesting Party's performance,
and (iii) if Lessor is the Requesting Party, not more than one month's Rent has
been paid in advance. Prospective purchasers and encumbrancers may rely upon the
Requesting Party's Estoppel Certificate, and the Responding Party shall be
estopped from denying the truth of the facts contained in said Certificate.

                                    PAGE 9                   Initials /s/
                                                                     ----------
<PAGE>

           (c) If Lessor desires to finance, refinance, or sell the Premises, or
any part thereof, Lessee and all Guarantors shall deliver to any potential
lender or purchaser designated by Lessor such financial statements 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.  Definition of Lessor. 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 this Lease, Lessor
shall deliver to the transferee or assignee (in cash or by credit) any unused
Security Deposit held by Lessor. Except as provided in Paragraph 15, upon such
transfer or assignment and delivery of the Security Deposit, and the
transferee's or assignee's written assumption, 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. Notwithstanding
the above, and subject to the provisions of Paragraph 20 below, the original
Lessor under this Lease, and all subsequent holders of the Lessor's interest in
this Lease shall remain liable and responsible with regard to the potential
duties and liabilities of Lessor pertaining to Hazardous Substances as outlined
in Paragraph 6 above.

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.  Days. Unless otherwise specifically indicated to the contrary, the word
"days" as used in this Lease shall mean and refer to calendar days.

20.  Limitation on Liability. Subject to the provisions of Paragraph 17 above,
the obligations of Lessor under this Lease shall not constitute personal
obligations of the individual partners of Lessor or its or their individual
partners, directors, officers or shareholders, and Lessee shall not seek
recourse against the individual partners of Lessor, or its or their individual
partners, directors, officers or shareholders, or any of their personal assets
for such satisfaction.

21.  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.

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.
Brokers have no  responsibility with respect thereto respect to any default or
breach hereof by either Party. The liability (including court costs and
Attorneys' fees), of any Broker with respect to negotiation, execution, delivery
or performance by either Lessor or Lessee under this Lease or any amendment or
modification hereto shall be limited to an amount up to the fee received by such
Broker pursuant to this Lease; provided, however, that the foregoing limitation
on each Broker's liability shall not be applicable to any gross negligence or
willful misconduct of such Broker.

23.  Notices.

     23.1  Notice Requirements. All notices required or permitted by this Lease
shall be in writing and may be delivered in person (by hand or by courier) or
may be sent by regular, certified or registered mail or U.S. PostaI 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 notices. Either Party may by written
notice to the other specify a different address for notice, except that upon
Lessee's taking possession of the Premises, the Premises shall constitute
Lessee's address for notice. a copy of all notices to Lessor shall be
concurrently transmitted to such party or parties at such addresses as Lessor
may from time to time hereafter designate in writing.

     23.2  Date of Notice. 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 three (3) days after the same
is addressed as required herein and three (3) days with postage prepaid. Notices
delivered by United States Express Mail or overnight courier that guarantee next
day delivery shall be deemed given twenty-four (24) hours after delivery of the
same to the Postal Service or courier. Notices transmitted by facsimile
transmission or similar means shall be deemed delivered upon telephone
confirmation of receipt, provided a copy is also delivered via delivery or mail.
If notice is received on a Saturday, 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 of 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. The acceptance of Rent by
Lessor shall not be a waiver of any Default or Breach by Lessee. Any payment by
Lessee may be accepted by Lessor on account of monies 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 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 termination of this Lease.
In the event that Lessee holds over, then the Base Rent shall be increased to
one hundred fifty percent (150%) of the Base Rent applicable during the month
immediately preceding the expiration or termination. Nothing contained herein
shall be construed as consent by Lessor to any holding over by Lessee.

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.

28.  Covenants and Conditions; Construction of Agreement. All provisions of this
Lease to be observed or performed by Lessee are both covenants and conditions.
In construing this Lease, all headings and titles are for the convenience of the
Parties only and shall not be considered a part of this Lease. Whenever required
by the context, the singular shall include the plural and vice versa. This Lease
shall not be construed as if prepared by one of the Parties, but rather
according to its fair meaning as a whole, as if both Parties had prepared it.

29.  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 upon the Premises, to any and all advances made on the security
thereof, and to all renewals, modifications, and extensions thereof. Lessee
agrees that the holders of any such Security Devices (in this Lease together
referred to as "Lessor's Lender") shall have no liability or obligation to
perform any of the obligations of Lessor under this Lease. Any Lender may elect
to have this Lease and/or any Option granted hereby superior to the lien of its
Security Device by giving written notice thereof to Lessee, whereupon 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

                                    PAGE 10                  Initials /s/
                                                                     ----------
<PAGE>

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, or (iii) be bound by prepayment of more than one (1) month's 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 a commercially reasonable non-disturbance
agreement (a "Non-Disturbance Agreement") from the Lender which Non-Disturbance
Agreement provides that Lessee's possession of the Premises, 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. Further, within sixty (60) days after the execution of this Lease,
Lessor shall use its commercially reasonable efforts to obtain a Non-Disturbance
Agreement from the holder of any pre-existing Security Device which is secured
by the Premises. In the event that Lessor is unable to provide the
Non-Disturbance Agreement within said sixty (60) days, then Lessee may, at
Lessee's option, directly contact Lessor's lender and attempt to negotiate for
the execution and delivery of a Non-Disturbance Agreement.

     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
subordination, attornment and/or Non-Disturbance Agreement provided for herein.

31.  Attorneys' Fees. If any Party or Broker brings an action or proceeding
involving the Premises to enforce the terms hereof or to declare rights
hereunder, the Prevailing Party (as hereafter defined) in any such proceeding,
action, or appeal thereon, shall be entitled to reasonable attorneys' 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 or 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 attorneys' fees award shall not be computed
in accordance with any court fee schedule, but shall be such as to fully
reimburse all attorneys' fees reasonably incurred. In addition, Lessor shall be
entitled to attorneys' 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 as Lessor may deem necessary.
All such activities shall be without abatement of rent or liability to Lessee.
Lessor may at any time place on the Premises any ordinary "For Sale" signs and
Lessor may during the last six (6) months of the term hereof place on the
Premises any ordinary "For Lease" signs. Lessee may at any time place on or
about the Premises any ordinary "For Sublease" sign.

33.  Auctions. Lessee shall not conduct, nor permit to be conducted, any auction
upon the Premises without Lessor's prior written consent. Lessor shall not be
obligated to exercise any standard of reasonableness in determining whether to
permit an auction.

34.  Signs. Except for ordinary "For Sublease" signs, Lessee shall not place any
sign upon the Premises without Lessor's prior written consent. All signs must
comply with all Applicable Requirements.

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, that Lessor may elect to continue any one or all
existing subtenancies. Lessor's failure within ten (10) days following any such
event to elect 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.  Consents. Except 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'
and other consultants' fees) incurred in the consideration of, or response to, a
request by Lessee for any Lessor consent, including, but not limited to,
consents to an assignment, a subletting or the presence or use of a Hazardous
Substance, shall be paid by Lessee upon receipt of an invoice and supporting
documentation therefor. Lessor's consent to any act, assignment or subletting
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. 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. In the event that either Party disagrees with any determination made by
the other hereunder and reasonably requests the reasons for such determination,
the determining party shall furnish its reasons in writing and in reasonable
detail within ten (10) business days following such request.

37.  Guarantor.

     37.1  Execution. The Guarantors, if any, shall each execute a guaranty in
the form most recently published by the American Industrial Real Estate
Association, and each such Guarantor shall have the same obligations as Lessee
under this Lease.

     37.2  Default. It shall constitute a Default of the Lessee if any Guarantor
fails or refuses, upon request to provide: (a) evidence of the execution of the
guaranty, including the authority of the party signing on Guarantor's behalf to
obligate Guarantor, and in the case of a corporate Guarantor, a certified copy
of a resolution of its board of directors authorizing the making of such
guaranty, (b) current financial statements, (c) a Estoppel Certificate, or (d)
written confirmation that the guaranty is still in effect.

38.  Quiet Possession. Subject to payment by Lessee of the Rent 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 and
quiet enjoyment of the Premises during the term hereof.

39.  Options.

     39.1  Definition. "Option" shall mean: (a) the right to extend the term of
or renew this Lease or to extend or renew any lease that Lessee has on other
property of Lessor; (b) the right of first refusal or first offer to lease
either the Premises or other property of Lessor; (c) the right to purchase or
the right of first refusal to purchase the Premises or 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, and cannot be assigned or
exercised by anyone other than said original Lessee and only while the original
Lessee is in full possession of the Premises and, if requested by Lessor, with
Lessee certifying that Lessee has no intention of thereafter assigning or
subletting.

     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 have been validly exercised.

     39.4  Effect of Default on Options.

           (a) Lessee shall have no right to exercise an Option: (i) during the
period commencing with the giving of any notice of Default and continuing until
said Default is cured, (ii) during the period of time any Rent is unpaid
(without regard to whether notice thereof is given Lessee), (iii) during the
time Lessee is in Breach of this Lease, or (iv) in the event that Lessee has
been given three (3) or more notices of separate Default, 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) 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 prior to the commencement of the extended term, (i) Lessee fails to
pay Rent for a period of thirty (30) days after such Rent becomes due (without
any necessity of Lessor to give notice thereof), (ii) Lessor gives to Lessee
three (3) or more notices of separate Default during any twelve (12) 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 a part of a group of buildings
controlled by Lessor, Lessee agrees that it will observe all reasonable rules
and regulations which Lessor may make from time to time for the management,
safety, and care of said properties, including

                                    PAGE 11                  Initials
                                                                     ----------
<PAGE>

the care and cleanliness of the grounds and including the parking, loading and
unloading of vehicles, 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.

43.  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.

44.  Authority. If either Party hereto is a corporation, trust, limited
liability company, partnership, or similar entity, 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. Each party
shall, within thirty (30) days after request, deliver to the other party
satisfactory evidence 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 either Party or their agent and
submission of same to the other Party shall not be deemed an offer to lease to
the other Party. This Lease is not intended to be binding until executed and
delivered 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. 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 a Lender in connection with the obtaining of normal financing or
refinancing of the Premises.

48.  Multiple Parties. If more than one person or entity is named herein as
either Lessor or Lessee, such multiple Parties shall have joint and several
responsibility to comply with the terms of this Lease.

49.  Mediation and Arbitration of Disputes. An Addendum requiring the Mediation
and/or the Arbitration of all disputes between the Parties and/or Brokers
arising out of this Lease [ ] is [X] is not attached to this Lease.

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.

-------------------------------------------------------------------------------
ATTENTION: NO REPRESENTATION OR RECOMMENDATION IS MADE BY THE AMERICAN
---------
INDUSTRIAL REAL ESTATE ASSOCIATION OR BY ANY BROKER AS TO THE LEGAL
SUFFICIENCY, LEGAL EFFECT, OR TAX CONSEQUENCES OF THIS LEASE OR THE
TRANSACTION TO WHICH IT RELATES. THE PARTIES ARE URGED TO:

1. SEEK ADVICE OF COUNSEL AS TO THE LEGAL AND TAX CONSEQUENCES OF THIS LEASE.
2. RETAIN APPROPRIATE CONSULTANTS TO REVIEW AND INVESTIGATE THE CONDITION OF
THE PREMISES. SAID INVESTIGATION SHOULD INCLUDE BUT NOT BE LIMITED TO: THE
POSSIBLE PRESENCE OF HAZARDOUS SUBSTANCES, THE ZONING OF THE PREMISES, THE
STRUCTURAL INTEGRITY, THE CONDITION OF THE ROOF AND OPERATING SYSTEMS, AND THE
SUITABILITY OF THE PREMISES FOR LESSEE'S INTENDED USE.

WARNING: IF THE PREMISES ARE LOCATED IN A STATE OTHER THAN CALIFORNIA, CERTAIN
-------
PROVISIONS OF THE LEASE MAY NEED TO BE REVISED TO COMPLY WITH THE LAWS OF THE
STATE IN WHICH THE PREMISES ARE LOCATED.
-------------------------------------------------------------------------------


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

Executed at: ADVANTECH                  Executed at: Sunnyvale, CA
            ----------------------                  ---------------------------

on: 1-3-2000                            on: Nov 19, 1999
   -------------------------------         ------------------------------------
By LESSOR:                              By LESSEE:
    American Advantech Corporation                 Somnus Medical Technologies
   -------------------------------                 ----------------------------
                                                   285 N. Wolfe Road
                                                   ----------------------------
                                                   Sunnyvale, CA 94086
                                                   ----------------------------

By: /s/ Thomas Chen                     By: /s/ John G. Shulte
   ------------------------------          ------------------------------------
Name Printed: Thomas Chen               Name Printed: John G. Shulte
             --------------------                    --------------------------
Title: General Manager                  Title: President and CEO
      ---------------------------             ---------------------------------

By: /s/ Lucia Wang                      By: /s/ Casey McGlynn
   ------------------------------          ------------------------------------
Name Printed: Lucia Wang                Name Printed: Casey McGlynn
             --------------------                    --------------------------
Title: Secretary                        Title: Secretary
      ---------------------------             ---------------------------------
Address: 750 E Arques Ave               Address: 650 Page Mill Rd., WSGR
        -------------------------               -------------------------------
         Sunnyvale, CA 94086                     Palo Alto, CA 94304
        -------------------------               -------------------------------
Telephone: (408) 245-6678               Telephone: (     )
          -----------------------                 -----------------------------
Facsimile: (408) 245-5678               Facsimile: (     )
          -----------------------                 -----------------------------
Federal ID No. 68-0144624               Federal ID No. 27-0423465
              -------------------                     -------------------------

NOTE:  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, 700
       So. Flower Street, Suite 600, Los Angeles, California 90017. (213) 687-
       8777. Fax No. (213) 687-8616

                                       12
<PAGE>

                               ADDENDUM TO LEASE

     This Addendum is attached to, and forms a part of, the Standard
Industrial/Commercial Single-Tenant Lease (the "Lease") made by and between
American Advantech Corporation, a California corporation, as Lessor, and Somnus
Medical Technologies, Inc., a Delaware corporation, as Lessee, and dated as of
November 19, 1999.
         --

50.  The Base Rent under paragraph 1.5 shall be the sum of $32,000.00 per month
     for the period from the Commencement Date until January 31, 2001 and the
     sum of $33,000.00 per month from February 1, 2001 through the Expiration
     Date. During each twelve-month period (commencing March 1, 2002 and each
     anniversary of that date) within the Extended Term of this Lease (as
     defined below), the Base Rent shall be the fair rental value of the
     Premises for such twelve-month period, as determined either by (a)
     agreement between Lessor or Lessee in writing or (b) by appraisal done by a
     commercial real-estate broker having at least five (5) years experience in
     leasing properties comparable to the Premises within the City of Sunnyvale
     and/or the City of Santa Clara, California. Lessor and Lessee shall, in
     good faith, attempt to agree on the selection of the appraiser at least 60
     days before the beginning of the twelve-month period in question. Should
     they fail to agree by that date, then either Lessor or Lessee may apply to
     the South Bay Association of Commercial/Industrial Brokers for appointment
     of the appraiser. The appraiser's determination shall be final and binding
     on Lessor and Lessee. In no event shall the Base Rent for any twelve-month
     period during the Original Term or Extended Term be decreased from the Base
     Rent in effect for the preceding twelve-month period, notwithstanding the
     fair rental value determined by appraisal.

51.  Lessee shall have the right to extend the Original Term for a period of
     three (3) years (the "Extended Term") by giving written notice of Lessee's
     election to Lessor not sooner than nine (9) and not later than six (6)
     months before the expiration of the Original Term, provided Lessee is not
     in default under the Lease on the date of such notice or at the expiration
     of the Original Term.

52.  Paragraph 2.2 of the Lease is modified by adding the following sentence at
     the end thereof: "Notwithstanding
<PAGE>

     any other provision of this paragraph to the contrary, Lessee shall have no
     obligation to correct any defect in the structural portions of the roof,
     foundations and bearing walls, if such defect existed on the Early
     Possession Date."

53.  Paragraph 2.3(b) of the Lease is modified by adding the following sentence
     at the end thereof: "Notwithstanding any other provision of this paragraph
     and paragraph 7.1(c) to the contrary, for the purpose of allocating the
     cost of any such Capital Expenditure which consists of the remediation of
     any Hazardous Substance, the remediation shall be deemed to possess a
     depreciable useful life of ten (10) years."

54.  Paragraph 2.4 of the Lease is modified by adding the following sentence at
     the end thereof: ". . . and (c) Lessee's acknowledgment in this paragraph
     is made in reliance upon the warranties given by Lessor in paragraph 2.2
     above."

55.  Paragraph 6.2(d) of the Lease is modified by adding the following sentence
     at the end thereof: "Lessee's indemnity shall not apply to any Hazardous
     Substance that existed on the Premises before the Early Occupancy Date."

56.  Paragraph 6.2(g) of the Lease is modified by adding the following sentence
     at the end thereof: "If Lessor's investigation or remediation prevents
     Lessee from occupying any portion of the building on the Premises, then
     Base Rent shall be abated, during the period of time that Lessee is
     prevented from occupying that portion, in proportion to the percentage of
     the interior space of the entire building that Lessee is prevented from
     occupying."

57.  Paragraph 7.2 of the Lease is modified by adding the following sentence at
     the end thereof: "Notwithstanding any other provision of this paragraph and
     paragraph 7.1(a) above to the contrary, Lessor's obligation to repair and
     maintain the Premises shall extend to the structural portions of the
     foundation, roof, and walls of the building, unless Lessee's Alterations or
     activities create the need for such repair or maintenance. Lessee shall pay
     for only that portion of the cost of such structural item replaced which is
     allocable to the remaining Original Term of this Lease (including any
     Extended Term) as compared with the depreciable, useful life of the item."

                                       14
<PAGE>

58.  Paragraph 8.4(b) of the Lease is deleted.

59.  Paragraph 9.2 of the Lease is modified by adding the following sentence
     immediately preceding the second to last sentence thereof: "Lessor's
     failure to deliver such written notice within such ten (10) day period
     shall be conclusively deemed to constitute Lessor's election to terminate
     the Lease."

60.  Paragraph 9.3 of the Lease is modified by adding the following sentence
     immediately after the second sentence thereof: "Basic Rent shall be abated
     during the period of time between the date on which the Partial Damage
     occurred and the date of termination of the Lease in proportion to the
     percentage of the interior space of the building that Lessee is prevented
     from occupying because of the Partial Damage."

61.  Paragraph 9.6(b) of the Lease is modified by adding the following sentence
     at the end thereof: "Lessor shall use due diligence in commencing such
     repair or restoration."

62.  Paragraph 10.1 of the Lease is modified by adding the following sentence at
     the end thereof: "In the case of an assessment against the Premises whose
     proceeds pay a bonded indebtedness of the assessing agency, only that
     portion of the assessment corresponding to annual installment on the bond
     amortized over the maximum term of the bond, together with interest at the
     rate of ten percent (10%) per annum on the unamortized portion of principal
     of the bond, shall be included in Real Property Taxes for any such tax
     year."

63.  Paragraph 12.1(b) of the Lease is deleted and the following substituted in
     its place: "12.1(b) The acquisition of all of the outstanding shares of
     Lessee by a single person or entity, whether or not followed by a merger of
     Lessee with another corporation."

64.  Paragraphs 1.4 and 3.2 of the Lease concerning Early Possession is modified
     by adding the following: "Commencing on December 1, 1999 Lessee shall have
     the right to occupy approximately 4,100 square feet of the building on the
     Premises comprising the area marked on Exhibit 1, attached hereto and
     incorporated herein by this reference (the "Occupied Area"). The period of
     Early Occupancy shall end on the Commencement Date. During the period of
     Early Occupancy Lessee shall pay rent to Lessor at the rate of $9,225.00
     per month; and such rent shall be pro-rated for any period of Early
     Occupancy which is a fraction of one month.
<PAGE>

     Notwithstanding any provision of the Lease to the contrary, during the
     period of Early Occupancy Lessor shall provide all utilities, shall be
     obligated for all maintenance and repair, shall provide its customary
     security service, and shall allow Lessee full and unrestricted access the
     Occupied Area. Lessee shall maintain its own insurance coverage for damage
     to its personal property and for workmen's compensation and for public
     liability in amounts that would otherwise be required under the Lease. The
     following provisions of the Lease shall not take effect during the period
     of Early Occupancy: Paragraphs 1.5, 10, 11. Effective January 15, 2000,
     Lessee shall have the right to occupy the entire Premises under all terms
     and conditions of the Lease; provided that Lessee shall not be obligated
     to pay Basic Rent until the Commencement Date (January 25, 2000)."

LESSEE

Somnus Medical Technologies, Inc.,
A Delaware corporation


 /s/ John G. Shulte                     Dated:   Nov 19  , 1999
-------------------------                     ----------
By: John G. Shulte,
   ----------------------
Its President


 /s/Casey McGlynn                       Dated:   Nov 19  , 1999
------------------------                      ----------
By: Casey McGlynn
   ---------------------
Its Secretary


LESSOR

American Advantech Corporation,
A California corporation


By: /s/ (illegible)                   Dated:  1-3-2000
    --------------------                      ----------,
Its President


   /s/ Lucia Wang                       Dated:   Dec 22  , 1999
------------------------                      -----------
By: Lucia Wang
   ---------------------
Its Secretary

                                       16
<PAGE>

                                   EXHIBIT 1



                       [BUILDING FLOORPLAN APPEARS HERE]

                        "OCCUPIED AREA" OUTLINED IN RED
                        -------------------------------

                                       17