<PAGE>   1
                                                                   EXHIBIT 10.1

                                      LEASE


                                 By and Between


                          ARE-METROPOLITAN GROVE I, LLC


                                       and


                               DIGENE CORPORATION

<PAGE>   2
                                TABLE OF CONTENTS

LEASE ....................................................................   -4-
      1.   Lease of Premises..............................................   -4-
      2.   Basic Lease Provisions.........................................   -4-
      3.   Term...........................................................   -6-
      4.   Possession and Commencement Date...............................   -7-
      5.   Rent...........................................................  -10-
           5.1.     Annual Base Rent......................................  -10-
           5.2.     Additional Rent.......................................  -10-
           5.3.     Improvement Rent......................................  -11-
      6.   Operating Expenses.............................................  -12-
      7.   Rentable Area..................................................  -18-
      8.   Security Deposit...............................................  -19-
      9.   Right of First Offer to Lease Additional Space. ...............  -20-
      10.  Use............................................................  -22-
      11.  Brokers........................................................  -24-
      12.  Holding Over...................................................  -25-
      13.  Taxes on Tenant's Property.....................................  -25-
      14.  Project Common Areas, Parking Facilities.......................  -26-
      15.  Utilities and Services.........................................  -26-
      16.  Alterations....................................................  -28-
           16.10.   Right to Expand Building..............................  -31-
      17.  Repairs and Maintenance........................................  -31-
      18.  Liens..........................................................  -32-
      19.  Indemnification and Exculpation................................  -32-
      20.  Insurance - Waiver of Subrogation .............................  -34-
      21.  Damage or Destruction..........................................  -36-
      22.  Eminent Domain.................................................  -38-
      23.  Defaults and Remedies..........................................  -39-
      24.  Assignment or Subletting.......................................  -43-
      25.  Attorneys' Fees................................................  -47-
      26.  Bankruptcy.....................................................  -47-
      27.  Estoppel Certificate...........................................  -48-
      28.  Joint and Several Obligations..................................  -48-
      29.  Definition of Landlord; Limitation of Landlord's Liability.....  -48-
      30.  Project Control by Landlord....................................  -50-
      31.  Quiet Enjoyment................................................  -51-
      32.  Quitclaim Deed.................................................  -51-
      33.  Rules and Regulations..........................................  -51-
      34.  Subordination and Attornment...................................  -51-
      35.  Surrender......................................................  -52-
      36.  Waiver and Modification........................................  -53-

<PAGE>   3
      37.  Waiver of Jury Trial and Counterclaims.........................  -53-
      38.  Hazardous Materials............................................  -53-
           38.1.    Prohibition/Compliance. ..............................  -53-
           38.2.    Business..............................................  -54-
           38.4.    Testing...............................................  -55-
           38.5.    Underground Tanks.....................................  -55-
           38.6.    Indemnification. .....................................  -55-
           38.7.    Survival..............................................  -56-
      39.  Right to Extend Term...........................................  -56-
      40.  Miscellaneous..................................................  -57-
           40.2.    FDA Rules and Regulation..............................  -57-
           40.3.    ......................................................  -58-
           40.4.    Terms and Headings....................................  -58-
           40.5.    Examination of Lease..................................  -58-
           40.6.    Time.  ...............................................  -58-
           40.7.    Covenants and Conditions..............................  -58-
           40.8.    Consents..............................................  -58-
           40.9.    Entire Agreement......................................  -58-
           40.10.   Severability. ........................................  -58-
           40.11.   Recording.............................................  -59-
           40.12.   Impartial Construction................................  -59-
           40.13.   Inurement. ...........................................  -59-
           40.14.   Notices.  ............................................  -59-
           40.15.   Maryland Jurisdiction. ...............................  -59-
           40.16.   Authority.............................................  -59-
           40.17.   ......................................................  -59-
      41.  Defined Terms..................................................  -60-

EXHIBITS .................................................................  -64-

      EXHIBIT "A".........................................................  -65-
      EXHIBIT "B".........................................................  -66-
      EXHIBIT "C".........................................................  -67-
      EXHIBIT "D".........................................................  -68-
      EXHIBIT "E".........................................................  -69-
      EXHIBIT "F".........................................................  -70-
      EXHIBIT "G".........................................................  -71-
      EXHIBIT "H".........................................................  -72-
      EXHIBIT "I".........................................................  -78-
      EXHIBIT "J".........................................................  -79-
      EXHIBIT "K".........................................................  -85-
      SCHEDULE 1..........................................................  -86-


                                        i

<PAGE>   4
                                      LEASE

         THIS LEASE is made as of March 2, 1998 (the "Effective Date"), by and
between ARE-METROPOLITAN GROVE I, LLC, a Delaware limited liability company
("Landlord"), and DIGENE CORPORATION, a Delaware corporation ("Tenant"). Certain
capitalized terms used but not otherwise defined elsewhere in this Lease shall
have the meaning ascribed thereto in Section 39.

1.       Lease of Premises

         1.1. Landlord hereby leases and demises to Tenant, and Tenant hereby
leases and hires from Landlord, upon the terms and conditions hereof those
certain premises (the "Demised Premises") within the building to be constructed
(the "Building") on the land cross- hatched in Exhibit "A" attached hereto (the
"Land"), and to have the mailing address set forth in Section 2.1.1. The Demised
Premises are shown on the plans attached hereto as Exhibit "B" and are situated
on all floors and/or suites in the Building. The Land upon which the Building is
located, the Building, and any other building located thereon and all
landscaping, parking facilities, and other improvements and appurtenances
related thereto, including, without limitation, driveways, sidewalks, parking
areas, and landscaped areas shall be a part of the development to be constructed
known as Metropolitan Grove Park and/or Alexandria Research Center, the site
plan and legal description for which is attached hereto as Exhibit "C" (the
"Project").

2.       Basic Lease Provisions

         2.1. For convenience of the parties, certain basic provisions of this
Lease are set forth herein. The provisions set forth herein are subject to the
remaining terms and conditions of this Lease and are to be interpreted in light
of such remaining terms and conditions.

              2.1.1.    Address of the Building: To be determined by City of
                        Gaithersburg, Maryland

              2.1.2.    [Intentionally Omitted]

              2.1.3.    Initial Area of Demised Premises, Building and Project,
                        all as subject to adjustments in accordance with Article
                        7.

                        (a) Initial Rentable Area of the Demised Premises:
                              90,000 sq. ft.

<PAGE>   5
                        (b) Initial Rentable Area of the Building:
                              90,000 sq. ft.

                        (c) Initial Rentable Area of the Project:
                              318,100 sq.ft.

              2.1.4.    Initial Annual Base Rent:

                        (90,000 rentable sq. ft.) x ($15.40 per rentable sq.
                        ft.) = $1,386,000, subject to adjustments of Rentable
                        Area pursuant to Article 7.

              2.1.5.    Initial Monthly Rental Installments:

                        (Initial Annual Base Rent) (divided by) 12 months =
                        $115,500 subject to adjustments of Annual Base Rent
                        pursuant to Section 2.1.4 and Section 5.1.3.

              2.1.6.    Tenant's Pro Rata Share of Building: 100 %

              2.1.7.    Initial Tenant's Pro Rata Share of Project: 28.29 %,
                        subject to adjustment as provided herein.

              2.1.8.    Term of Lease:

                        (a) Term Commencement Date: 
                        As defined in Section 4.2.

                        (b) Term Expiration Date:
                        Ten (10) years from the Term Commencement Date.

              2.1.9.    Security Deposit:

                        (Initial Monthly Rental Installment) x (3 months),
                        subject to increase in accordance with Article 8.

              2.1.10.   Permitted Use:

                        Pharmaceutical, biological or medical device research
                        laboratories and related manufacturing, warehouse,
                        distribution and office uses consistent with Article 10.

              2.1.11.   Address for Rent Payment:

                        135 N. Los Robles Ave., Suite 250
                        Pasadena, CA 91101
                        Attention: Corporate Secretary



                                       -3-

<PAGE>   6
                        Address for Notices to Landlord:

                        135 N. Los Robles Ave., Suite 250
                        Pasadena, CA 91101
                        Attention: Corporate Secretary

                        With a copy to:

                        11440 West Bernardo Court, Suite 170
                        San Diego, CA 92127
                        Attention: Gary A. Kreitzer, Esq.

                        Address for Notices to Tenant:

                        Prior to Term Commencement Date

                        9000 Virginia Manor Road
                        Beltsville, Maryland  20705
                        Attention: Mr. Charles M. Fleischman

                        From and after Term Commencement Date:

                        Address of the Building
                        Attention: Mr. Charles M. Fleischman

              2.1.12.   The following Exhibits and Schedule are attached hereto
                        and incorporated herein: A, B, C, D, E, F, G, H, I, J
                        and K and Schedule 1.

3.       Term

         3.1. This Lease shall take effect upon the Effective Date, and, except
as specifically otherwise provided within this Lease, each of the provisions
hereof shall be binding upon and inure to the benefit of Landlord and Tenant,
and each of their respective successors and permitted assigns, from and after
the Effective Date.

         3.2. The term of this Lease (the "Term") shall be that period from the
Term Commencement Date and through the Term Expiration Date subject to
terminations or extensions as otherwise provided herein, including, without
limitation, Tenant's right to terminate as provided in Section 3.3.


                                       -4-

<PAGE>   7
         3.3. Notwithstanding anything to the contrary contained herein, Tenant
shall have the right, in its sole and absolute discretion, to terminate this
Lease, which termination shall be effective at the end of the fifth year after
the Term Commencement Date, upon not less than twelve (12) months' prior written
notice to Landlord, which notice, as a condition to its effectiveness and the
effectiveness of any termination, shall be accompanied by the payment of the
Termination Amount. Upon the effective date of such termination made pursuant to
this paragraph, this Lease shall terminate and all of the rights and obligations
of the parties hereunder shall thereafter cease and terminate, except pursuant
to any provision which expressly survives the termination hereof, including
without limitation, Tenant's indemnification obligation set forth in Article 38
of this Lease, and Tenant's obligations and liabilities which accrue or arise
prior to the termination date of this Lease, including, without limitation,
Tenant's obligation to pay any and all Rent which accrued prior to such
termination date.

4.       Possession and Commencement Date

         4.1. Landlord shall tender possession of the Demised Premises and the
Land to Tenant on or before the Target Term Commencement Date (as the same is
extended due to Tenant-Caused Delays or Force-Majeure Delays) with Landlord's
Work Substantially Completed.

         4.2. The Term Commencement Date shall be the date which is three (3)
Business Days after the Substantial Completion of Landlord's Work, provided that
in the event Landlord intends to deliver the Demised Premises with Landlord's
Work Substantially Complete on any date other than the Target Term Commencement
Date (as extended due to Tenant-Caused Delays or Force-Majeure Delays), Landlord
shall deliver to Tenant written notice of such other delivery date no less than
forty-five (45) days prior to such other delivery date. Landlord and Tenant
shall each execute and deliver to the other written acknowledgment in the form
attached hereto as Exhibit "D" of the Term Commencement Date and the Term
Expiration Date when the same are established; provided, however, the failure to
execute and deliver such acknowledgment shall not affect Landlord's or Tenant's
rights or liabilities hereunder.

         4.3. Tenant agrees that, in the event Landlord fails to tender
possession of the Demised Premises and the Land on or before the Target Term
Commencement Date, Landlord shall not be liable to Tenant for any loss or damage
resulting therefrom, and this Lease shall not be void or voidable except as
provided below in Section 4.4. In such event, however, Tenant shall not be
liable for Annual Base Rent, Improvement Rent or Operating Expenses until the
Term Commencement Date. In the event the Term Commencement Date is delayed
beyond the Target Term Commencement Date (as extended due to Tenant-Caused
Delays or Force-Majeure Delays), Tenant shall receive one (1) day of abatement
of Annual Base Rent for every day the Term Commencement Date is delayed beyond
the Target Term Commencement Date (as extended due to Tenant-Caused Delays or
Force-Majeure Delays) up to and including



                                       -5-

<PAGE>   8
the date (the "First Delayed Delivery Date") which is thirty (30) days after the
Target Term Commencement Date (as extended due to Tenant-Caused Delays or
Force-Majeure Delays). In the event the Term Commencement Date is delayed beyond
the First Delayed Delivery Date (as extended due to Tenant-Caused Delays or
Force-Majeure Delays), Tenant shall receive three (3) days of abatement of the
Annual Base Rent for every day the Term Commencement Date is delayed beyond the
First Delayed Delivery Date (as extended due to Tenant-Caused Delays or
Force-Majeure Delays) up to and including the date (the "Second Delayed Delivery
Date") which is thirty (30) days after the First Delayed Delivery Date (as
extended due to Tenant-Caused Delays or Force-Majeure Delays).

         4.4. In the event the Term Commencement Date is delayed beyond the
Second Delayed Delivery Date (as extended due to Tenant-Caused Delays or
Force-Majeure Delays), Tenant shall have the right (time being of the essence)
to terminate this Lease exercisable only prior to the earlier to occur of (A)
the date which is fifteen (15) days after the Second Delayed Delivery Date (as
extended due to Tenant-Caused Delays and Force-Majeure Delays), and (B) the Term
Commencement Date, by giving Landlord five (5) days written notice of Tenant's
election to terminate the Lease. In the event Tenant so terminates this Lease,
(i) as of the effective date of such termination this Lease shall be of no
further force or effect and neither party shall have any further rights or
obligations hereunder other than pursuant to any provision hereof which
expressly survives the termination of this Lease, and (ii) Landlord shall,
within ninety (90) days following the effective date of such termination, pay to
Tenant the total amount of Annual Base Rent that would have been abated through
the effective date of such termination had the Lease not been terminated (which
obligation shall survive such termination). In the event that Tenant fails to
timely terminate this Lease (time being of the essence), this Lease will
continue in full force and effect, no additional amounts of Rent will be abated
and Tenant will have no further rights to terminate this Lease due to any delays
in the Term Commencement Date. Notwithstanding anything to the contrary set
forth herein, in the event the Term Commencement Date has not occurred on or
before December 31, 2000, this Lease shall terminate and be of no further force
or effect and neither party shall have any further rights or obligations
hereunder other than pursuant to any provision hereof which expressly survives
the termination of this Lease

         4.5. In the event that Landlord fails to acquire title to the Project
(as evidenced by the unconditional delivery of a deed to the Project) by May 5,
1998, Tenant shall have the right to terminate this Lease at any time on or
before June 5, 1998, by giving Landlord fifteen (15) days written notice of
Tenant's election to terminate the Lease, and, as of the effective date of such
termination, this Lease shall be of no further force or effect and neither party
shall have any further rights or obligations hereunder other than pursuant to
any provision hereof which expressly survives the termination of this Lease.

         4.6. In the event that any of the events (each, a "Milestone Event")
set forth on Schedule 1 attached hereto have not occurred on or before the date
(each, a "Milestone Date") set forth on Schedule 1 for each respective Milestone
Event (as the same may be extended due


                                       -6-

<PAGE>   9
to Tenant-Caused Delays and Force-Majeure Delays), Tenant shall have the right
to terminate this Lease by delivering to Landlord no later than five (5) days
after the applicable Milestone Date (as the same may be extended due to
Tenant-Caused Delays and Force-Majeure Delays) written notice of Tenant's
election to terminate this Lease, which termination shall be effective ten (10)
days after delivery of such notice by Tenant unless, within such ten (10) day
period, the applicable Milestone Event occurs, in which event Tenant's
termination election shall be of no force or effect and this Lease shall
continue in full force and effect. Upon the effective date of any termination
pursuant to this Section 4.6, this Lease shall be of no further force or effect
and neither party shall have any further rights or obligations hereunder other
than pursuant to any provision hereof which expressly survives the termination
of this Lease.

         4.7.  Landlord shall allow Tenant to enter upon the Demised Premises at
any time during normal business hours prior to the Term Commencement Date for
the purpose of performing Tenant's Work or to install any furnishings, fixtures
or equipment of Tenant, provided such entry does not unreasonably interfere with
the performance by Landlord of Landlord's Work and that Landlord shall have no
liability to Tenant for any damage to Tenant's furnishings, fixtures or
equipment. Such entry shall be subject to all the terms and conditions of this
Lease other than the payment of Annual Base Rent, Improvement Rent or Operating
Expenses.

         4.8.  Subject to all terms of this Lease, Tenant shall have access to
and full use of the Demised Premises and, subject to applicable law and
Force-Majeure, access to and use of the portions of the Land necessary for use
of the Demised Premises and parking as provided herein, twenty-four (24) hours a
day, seven (7) days a week during the Term.

         4.9.  Access to and possession of areas necessary for utilities,
services, safety and operation of the Project are reserved to Landlord.

         4.10. Landlord shall cause to be constructed the Tenant Improvements
pursuant to the Work Letter at a cost to Landlord not to exceed the Tenant
Improvement Allowance, which shall include the cost of construction, project
management by Landlord (which fee shall not exceed two and one-half percent
(2.5%) of each $10.00 per square foot increment of the Tenant Improvement
Allowance, or portion thereof, in excess of $25.00 per square foot of Rentable
Area), cost of space planning, architect, engineering and other related
services, building permits, and other planning and inspection fees. Tenant shall
have the right, upon written notice to Landlord and provided that no Default, or
event which with the giving of notice or the passage of time, or both, would
constitute an Default, has occurred and is continuing, to increase the amount of
the Tenant Improvement Allowance up to a maximum of $125.00 per square foot of
Rentable Area. If Landlord reasonably determines at any time that the total cost
of the Tenant Improvements will exceed the available Tenant Improvement
Allowance, then Tenant shall immediately, and as a condition to Landlord's
obligation to expend or disburse any portion of the Tenant Improvement
Allowance, deposit in an escrow account, under terms reasonably acceptable to
Landlord, an amount sufficient to pay such



                                       -7-

<PAGE>   10
excess. Tenant shall have until the first anniversary of the Term Commencement
Date to increase the amount of the Tenant Improvement Allowance as provided
herein and expend any unused portion of the Tenant Improvement Allowance (as may
have been increased as provided herein), after which date Landlord's obligation
to fund such increase of the Tenant Improvement Allowance or to fund the costs
of the Tenant Improvements out of the Tenant Improvement Allowance shall expire.

         4.11. Landlord shall cause the Land to be a legally subdivided parcel
assessed for tax purposes separate and apart from the remainder of the Project.
Such legal subdivision shall be a condition precedent to Substantial Completion
of Landlord's Work.

5.       Rent

         5.1. Annual Base Rent

              5.1.1. Tenant agrees, commencing on the Term Commencement Date, to
pay Landlord as the Annual Base Rent for the Demised Premises the sum set forth
in Section 2.1.4, subject to the increases provided in Section 5.1.3.

              5.1.2. The Annual Base Rent shall be paid in the equal monthly
installments set forth in Section 2.1.5, subject to the rental adjustments
provided in Section 5.1.3, each in advance on the first day of each and every
calendar month during the Term. Notwithstanding anything to the contrary set
forth herein, Tenant shall have no obligation to pay Annual Base Rent for any
periods prior to the Term Commencement Date.

              5.1.3. The Annual Base Rent shall be adjusted upward in the amount
of two and one half percent (2.5%) of the prior year's Annual Base Rent,
effective on each anniversary of the Term Commencement Date throughout the Term,
beginning on the first anniversary of the Term Commencement Date.

         5.2. Additional Rent

              5.2.1. In addition to the Annual Base Rent, Tenant agrees to pay
to Landlord as Additional Rent at times hereinafter specified in this Lease (i)
Tenant's Pro Rata Share of Building Operating Expenses set forth in Section
2.1.6, (ii) Tenant's Pro Rata Share of Project Operating Expenses set forth in
Section 2.1.7, and (iii) any other amounts that Tenant assumes or agrees to pay
under the provisions of this Lease that are owed to Landlord, including, without
limitation, any and all other sums that may become due by reason of any default
of Tenant or failure on Tenant's part to comply with the agreements, terms,
covenants, and conditions of this Lease to be performed by Tenant, after notice
and lapse of applicable cure period.



                                       -8-

<PAGE>   11
              5.2.2. The actual Tenant's Pro Rata Share of Project shall be
determined on or before the Term Commencement Date when the actual Rentable Area
of the Demised Premises, and the Project are established pursuant to Article 7.
Landlord and Tenant shall attach an acknowledgment of such actual Tenant's Pro
Rata Share of Project to this Lease as part of Exhibit "F"; provided, however,
failure to execute and deliver such acknowledgment shall not affect Landlord's
or Tenant's rights or liabilities hereunder.

              5.2.3. Other than as may be specifically provided herein or in the
Work Letter, Tenant shall have no obligation to pay Additional Rent for any
periods prior to the Term Commencement Date.

         5.3. Improvement Rent

              5.3.1. In the event that Tenant elects to increase the Tenant
Improvement Allowance pursuant to Section 4.10, in addition to the Annual Base
Rent, Tenant further agrees to pay to Landlord, commencing on the Term
Commencement Date, the Improvement Rent, calculated in accordance with this
Section 5.3 and subject to the increases provided in Section 5.3.3.

              5.3.2. The Improvement Rent shall be paid in equal monthly
installments, subject to the increases provided in Section 5.3.3, each in
advance on the first day of each and every calendar month during the Term.
Notwithstanding anything to the contrary set forth herein, Tenant shall have no
obligation to pay Improvement Rent for any periods prior to the Term
Commencement Date.

              5.3.3. The Improvement Rent shall be adjusted upward in the amount
of two and one half percent (2.5%) of the prior year's Improvement Rent,
effective on each anniversary of the Term Commencement Date throughout the Term,
beginning on the first anniversary of the Term Commencement Date.

              5.3.4. The initial Improvement Rent shall be equal to $1.25 per
square foot of Rentable Area for the first Ten Dollars ($10.00), or portion
thereof, of the Tenant Improvement Allowance actually expended in excess of
$25.00, plus $1.30 per square foot of Rentable Area for the next Ten Dollars
($10.00), or portion thereof, of the Tenant Improvement Allowance actually
expended in excess of $35.00, plus $1.35 per square foot of Rentable Area for
the next Ten Dollars ($10.00), or portion thereof, of the Tenant Improvement
Allowance actually expended in excess of $45.00, plus $1.40 per square foot of
Rentable Area for each additional Ten Dollars ($10.00), or portion thereof, of
the Tenant Improvement Allowance actually expended in excess of $55.00, plus
$1.45 per square foot of Rentable Area for each additional Ten Dollars ($10.00),
or portion thereof, of the Tenant Improvement Allowance actually expended in
excess of $85.00 up to the maximum Tenant Improvement Allowance pursuant to
Section 4.10.



                                       -9-


<PAGE>   12
              5.3.5. Notwithstanding anything to the contrary set forth herein,
Tenant shall have no obligation to pay Improvement Rent for any periods prior to
the Term Commencement Date.

         5.4. Annual Base Rent, Additional Rent and Improvement Rent shall
together be denominated "Rent". Rent shall be paid to Landlord, without
abatement, deduction, or offset, in lawful money of the United States of
America, at the office of Landlord as set forth in Section 2.1.11, or to such
other Person or at such other place as Landlord may from time designate in
writing. In the event the Term commences or ends on a day other than the first
day of a calendar month, then Rent for such fraction of a month shall be
prorated for such period on the basis of a thirty (30) day month and shall be
paid at the then current rate for such fractional month.

6.       Operating Expenses

         6.1. As used herein, (i) the term "Building Operating Expenses" shall
mean those Operating Expenses related to the Building, the Land and any other
area of the Project with respect to which Tenant has exclusive use, and (ii) the
term "Project Operating Expenses shall mean those Operating Expenses related to
the Project Common Areas. As used herein, the term "Operating Expenses", with
respect to Project Operating Expenses or Building Operating Expenses, as
applicable, shall include:

              6.1.1. Government impositions including, without limitation,
property tax costs consisting of real and personal property taxes and
assessments (including amounts due under any improvement bond or assessments
levied upon the Building or the Project, including the parcel or parcels of real
property upon which the Building or Project, and areas serving the Building or
the Project, are located) imposed by any governmental authority or agency; any
tax on or measured by gross rentals received from the rental of space in the
Building or the Project, or tax based on the square footage of the Demised
Premises, the Building, or the Project as well as any parking charges, utilities
surcharges, or any other costs levied, assessed or imposed by, or at the
direction of, or resulting from statutes or regulations, or interpretations
thereof, promulgated by any federal, state, regional, municipal or local
government authority in connection with the use or occupancy of the Building or
the Project or the parking facilities serving the Building or the Project; any
tax on this transaction or any document to which Tenant is a party creating or
transferring an interest in the Demised Premises (but excluding any documentary
transfer tax or recording tax); any fee for a business license to operate an
office building; and any expenses, including the reasonable cost of attorneys or
experts, reasonably incurred by Landlord in seeking reduction by the taxing
authority of the applicable taxes, less tax refunds obtained as a result of an
application for review thereof. Operating Expenses shall not include any net
income, franchise, capital stock, estate or inheritance taxes or taxes which are
the personal obligation of Landlord, Tenant or of another tenant of the Project
(collectively, "Excluded Taxes").



                                      -10-

<PAGE>   13
              6.1.2. All other costs of any kind paid or incurred by Landlord in
connection with the operation and maintenance of the Building or the Project
including, by way of examples and not as a limitation upon the generality of the
foregoing, costs of repairs and replacements to the Building or improvements
within the Project as appropriate to maintain the Building or the Project as
required hereunder as a first-class (but not necessarily state-of-the-art)
facility for the use permitted by Section 2.1.10, including, without limitation,
cleaning, windows, landscape and grounds, drives and parking areas; costs of
funding such reasonable reserves as Landlord, consistent with good business
practices, may establish to provide for future repairs and replacements; costs
of utilities and related services furnished to the Building or Project Common
Areas, including electricity, water, sewer, heat, air conditioning, ventilation,
telephone, refuse, and gas, and all related charges and deposits; security
services and devices; building supplies; maintenance and replacement to
equipment utilized for operation and maintenance of the Building or the Project;
license, permit, and inspection fees; sales, use and excise taxes on goods and
services purchased by Landlord in connection with the operation, maintenance, or
repair of the Project or the Building systems and equipment; telephone, postage,
stationary supplies and other expenses incurred in connection with the
operation, maintenance or repair of the Building or the Project; accounting,
legal, and other professional fees and expenses incurred in connection with the
Building or the Project; costs of insurance, including premiums and deductibles
for environmental insurance, public liability insurance, and property damage
insurance, and portions of insured losses paid by Landlord as part of the
deductible portion of such loss by reason of insurance policy terms; the cost of
furniture, draperies, carpeting, landscaping and other customary and ordinary
items of personal property provided by Landlord for use in the Building or
Project Common Areas or in the management office of the Building or the Project;
Project or Building management office rent or rental value for not more than
5,000 rentable square feet of space; costs of complying with any applicable
laws, hazardous waste remediation, and rules or regulations; and the costs of
any subsequent tenant or other capital improvement to the property reasonably
necessitated by good business practices and consistent with the use of the
Demised Premises as a first-class (but not necessarily state-of-the-art)
facility for the use permitted by Section 2.1.10, including, without limitation,
the costs of capital improvements required to cause the Building to comply with
any retroactive law, rule or regulation where such noncompliance is not a result
of Tenant's use of or alterations to the Demised Premises (which shall be
amortized over the useful life of the item in question, and only the annual
amortized amount shall be included as part of Operating Expenses, and the useful
life of such capital improvements shall be the same as set forth in the Internal
Revenue Code and the regulations promulgated therein, but in no event greater
than seven (7) years); the cost of any insured repairs (which shall be amortized
over the useful life of the item in question, and only the annual amortized
amount shall be included as part of Operating Expenses, and the useful life of
such repairs shall be the same as set forth in the Internal Revenue Code and the
regulations promulgated therein, but in no event greater than seven (7) years)
where insurance coverage for such repairs is denied or the cost of which is not
fully covered despite Landlord (i) maintaining in full force and effect all
insurance coverages required to be maintained under this Lease and (ii)
diligently filing and pursuing a claim for



                                      -11-

<PAGE>   14
coverage (but Landlord shall not be obligated to bring any suit or legal action
against the insurer); service contracts; costs of services of independent
contractors retained to do work of the nature or type referenced herein; and
costs of compensation (including employment taxes and fringe benefits) of all
Persons who perform regular and recurring duties connected with the day-to-day
operation and maintenance of the Building, the Project, their respective
equipment, the adjacent walks, landscaped areas, drives, and parking areas,
including without limitation, janitors, floor waxers, window-washers, watchmen,
gardeners, sweepers, and handymen and costs of management services by Landlord
or a third-party manager retained by Landlord, if any, which fee for property
management services shall be equal to two and one half percent (2.5%) of the
Annual Base Rent and the annual Improvement Rent due from Tenant.

              6.1.3. Notwithstanding the foregoing, Operating Expenses shall not
include:

                     a. any leasing commissions;

                     b. expenses which relate to preparation of rental space for
              a tenant;

                     c. expenses of initial development and capital improvement
              construction, including but not limited to, grading, paving,
              landscaping, and initial construction of Project monument signage
              exclusive of Tenant's lettering (as distinguished from maintenance
              repair and replacement of the foregoing);

                     d. legal expenses relating to other tenants;

                     e. costs of repairs to the extent reimbursed by payments
              received by Landlord of insurance proceeds;

                     f. interest upon loans to Landlord or secured by mortgage
              or deed of trust covering the Building or the Project or a portion
              thereof, debt amortization, ground rent, and sums due in
              connection with other types of financing, including, without
              limitation, rent under a sale-leaseback, (provided interest upon a
              government assessment or improvement bond payable in installments
              is an Operating Expense under Section 6.1.1 above);

                     g. salaries and travel expenses and office overhead
              expenses other than for employees and office uses to the extent
              related to the management and operation of the Building or
              Project;

                     h. depreciation claimed by Landlord for tax purposes
              (provided this exclusion of "depreciation" is not intended to
              delete from Operating Expenses actual costs of repairs and
              replacements and reasonable reserves in regard thereto which are
              provided for in Section 6.1.2 above);



                                      -12-


<PAGE>   15
                     i. Excluded Taxes;

                     j. professional fees and expenses, except as otherwise
              specifically provided for herein;

                     k. fines, penalties and late charges unless incurred as a
              result of any action or inaction of Tenant;

                     l. promotional, advertising, travel and entertainment
              expenses attributable to marketing of other leasable space in the
              Project other than Project signage in Project Common Areas;

                     m. management fees in excess of two and one-half percent
              (2.5%) per year;

                     n. the excess of any payments to Landlord or its affiliates
              for goods or services otherwise includable in Operating Expenses
              under any provision of this Lease over the market price at which
              the same goods or services can reasonably be obtained from another
              qualified party;

                     o. repairs covered by construction and equipment warranties
              or owing to a defect or omission in design for which a contractor,
              architect or engineer is liable, but only to the extent (1) such
              repairs are actually made by a third party under any applicable
              warranties, or (2) Landlord actually receives funds from such
              warranties; provided, that if any such third party warrantor,
              contractor, architect or engineer fails to perform under the
              applicable warranty or contract and Landlord is unwilling or
              unable to cause such performance, Tenant shall have the right upon
              not less than ten (10) days prior written notice to Landlord to
              enforce such warranty or contract against such contractor,
              architect or engineer, in which event Tenant shall indemnify and
              hold Landlord harmless from and against any loss, cost, damage or
              liability in connection with such enforcement;

                     p. the cost of collection of any obligation due Landlord
              from any other tenant;

                     q. any expense actually refunded or reimbursed by a tenant
              or other party including Tenant which is not otherwise an
              Operating Expense;

                     r. any expense incurred by reason of the gross negligence
              or wilful misconduct of Landlord or its officers, directors,
              employees, contractors or agents;



                                      -13-


<PAGE>   16
                     s. any loss resulting from Landlord's failure to correct
              any condition which Landlord is obligated to correct pursuant to
              any applicable law, rule or regulation or underwriter's violation
              notice unless such condition was caused by Tenant;

                     t. the costs of any pest control services, environmental
              audits or other similar types of services required due to the
              specific nature of any other tenant's use and not also required
              due in whole or in part to the specific nature of Tenant's use;
              and

                     u. the cost of any service for which Tenant contracts
              directly with a third party.

              6.1.4. In no event shall Tenant's Pro Rata Share of Project be
increased for any reason whatsoever except as the result of an increase in the
rentable square footage of the Demised Premises.

         6.2. Tenant shall pay to Landlord on the first day of each calendar
month of the Term, as Additional Rent, Landlord's estimate of Tenant's Pro Rata
Share of Building Operating Expenses and Tenant's Pro Rata Share of Project
Operating Expenses for such month. Any amount due for any period which is less
than a full month shall be prorated, based on a thirty (30) day month, for such
fractional month. Operating Expenses for the calendar year in which Tenant's
obligation to share therein commences and in the calendar year in which such
obligation ceases, shall be prorated based on a thirty (30) day month. Expenses
such as taxes, assessments and insurance premiums which are incurred for time
periods in excess of one (1) month shall be prorated based upon the time periods
for which such expenses are incurred so that the amounts attributed to the
Demised Premises relate in a reasonable manner to the time period for such
expenses during which Tenant has an obligation to share in Operating Expenses.

         6.3. Within ninety (90) days after the conclusion of each calendar year
(or such longer period as may be reasonably required), Landlord shall furnish to
Tenant a statement showing in reasonable detail the actual Operating Expenses
and Tenant's Pro Rata Share of Building Operating Expenses and Tenant's Pro Rata
Share of Project Operating Expenses for the previous calendar year. Any
additional sum due from Tenant to Landlord shall be immediately due and payable.
If the amounts paid by Tenant pursuant to Section 6.2 exceeds Tenant's Pro Rata
Share of Building Operating Expenses or Tenant's Pro Rata Share of Project
Operating Expenses for the previous calendar year, Landlord shall at Landlord's
option either (1) credit the excess to the next succeeding installments of
estimated Additional Rent or (2) pay the excess to Tenant within the earlier of
one hundred eighty (180) days after the conclusion of such calendar year or
thirty (30) days after delivery of such statement (provided that Landlord shall
elect clause (2) in the event that the Term has expired). The obligations under
this Section 6.3 shall survive the termination of expiration hereof.



                                      -14-


<PAGE>   17
         6.4. Landlord's annual statement shall be final and binding upon Tenant
unless within ninety (90) days after Tenant's receipt thereof, Tenant shall
contest any item therein by giving written notice to Landlord, specifying each
item contested and the reason therefor. If, during such ninety (90) day period,
Tenant contests the correctness of Landlord's statement of Tenant's Pro Rata
Share of Building Operating Expenses or Tenant's Pro Rata Share of Project
Operating Expenses, Landlord will provide Tenant with access to Landlord's books
and records and such information as Tenant reasonably determines to be
responsive to Tenant's questions. In the event that after Tenant's review of
such information, Landlord and Tenant cannot agree upon the amount of Tenant's
Pro Rata Share of Building Operating Expenses or Tenant's Pro Rata Share of
Project Operating Expenses, then Tenant shall have the right to have an
independent public accounting firm selected from among the ten (10) largest in
the United States hired by Tenant (at Tenant's sole cost and expense) and
approved by Landlord (which approval shall not be unreasonably withheld or
delayed) audit and/or review such Landlord's books and records for the year in
question (the "Independent Review"). The results of any such Independent Review
shall be binding on Landlord and Tenant. If the Independent Review shows that
Tenant's Pro Rata Share of Operating Expenses actually paid for the calendar
year in question exceeded Tenant's obligations for such calendar year, Landlord
shall pay the excess to Tenant within thirty (30) days after delivery of such
statement (provided, however, that in the event that the Independent Review
indicates that the amount of Operating Expenses paid by Tenant with respect to a
calendar year exceeded by more than ten percent (10%) the amount actually due
from Tenant, then Landlord shall reimburse Tenant for the cost of such
Independent Review). If the Independent Review shows that Tenant's payments of
Operating Expenses for such calendar year were less than Tenant's obligation for
the calendar year, Tenant shall pay the deficiency to Landlord within thirty
(30) days after delivery of such statement. The obligations under this Section
6.4 (including subsections) shall survive the expiration or termination hereof

              6.4.1. If the Independent Review shows that Tenant's Pro Rata
Share of Building Operating Expenses or Tenant's Pro Rata Share of Project
Operating Expenses actually paid for the calendar year in question exceeded
Tenant's obligations for such calendar year, Landlord shall at Landlord's option
either (1) credit the excess to the next succeeding installments of estimated
Additional Rent or (2) pay the excess to Tenant within thirty (30) days after
delivery of such statement.

              6.4.2. If the Independent Review shows that Tenant's payments of
Tenant's Pro Rata Share of Building Operating Expenses or Tenant's Pro Rata
Share of Project Operating Expenses for such calendar year were less than
Tenant's obligation for the calendar year, Tenant shall pay the deficiency to
the Landlord within thirty (30) days after delivery of such statement.

         6.5. Tenant shall not be responsible for Operating Expenses
attributable to the time period prior to the Term Commencement Date; provided,
however, if Landlord permits Tenant possession of the Demised Premises prior to
the Term Commencement Date, Tenant



                                      -15-


<PAGE>   18
shall be responsible for Operating Expenses resulting solely from the activities
of Tenant or its agents, employees or contractors from such earlier date of
possession. The responsibility of Tenant for Tenant's Pro Rata Share of Building
Operating Expenses and Tenant's Pro Rata Share of Project Operating Expenses
shall continue to the latest of (i) the date of termination of the Lease, (ii)
the date Tenant has fully vacated the Demised Premises (including, without
limitation, the removal of all items required hereby to be removed and the
completion of all procedures necessary to fully release and terminate any
permits or licenses restricting the use of the Demised Premises in any manner),
or (iii) the earlier of the Term Expiration Date or, if termination of the Lease
is due to the Default of Tenant, the date of rental commencement of a
replacement tenant (the collection of which if due to a Default of Tenant shall
be consistent with Article 23).

         6.6. Notwithstanding any other provision herein to the contrary (i) in
the event the Project is not at least ninety-five percent (95%) occupied on
average during any year of the Term, an adjustment shall be made by Landlord in
computing Tenant's Pro Rata Share of Project Operating Expenses for such year so
that Tenant's Pro Rata Share of Project Operating Expenses shall be computed for
such year as though the Project had been ninety-five percent (95%) occupied on
average during such year, and (ii) in no event shall Tenant's Pro Rata Share of
Project Operating Expenses exceed a fraction which has a its numerator 120,100
(representing the maximum square footage of the Building) and which has as its
denominator the square footage of the maximum permitted density shown on the
final site plan for the Project, as approved by the City of Gaithersburg,
Maryland. The parties agree that statements in this Lease to the effect that
Landlord is to perform certain of its obligations hereunder at its own or sole
cost and expense shall not be interpreted as excluding any cost from Operating
Expenses if such cost is an Operating Expense pursuant to the terms of this
Lease.

7.       Rentable Area

         7.1. The Initial Rentable Area set forth in Section 2.1.3 is an
estimate of the area which will, upon completion of development of the Building,
constitute the Rentable Area of the Demised Premises. Due to changes in
configurations which may be required in connection with development of the
Building, the Rentable Area applicable to Tenant is subject to modification.

         7.2. On or before the Term Commencement Date, the Project Architect
shall determine the actual Rentable Area of the Demised Premises and the Project
in accordance with the BOMA Standard, and Landlord and Tenant shall attach an
acknowledgment of such actual Rentable Area of the Demised Premises, the
Building, and the Project to this Lease as part of Exhibit "F". However, failure
to execute and deliver such acknowledgment shall not affect Landlord's or
Tenant's rights or liabilities hereunder.

         7.3. Review of allocations of Rentable Areas as between tenants of the
Project may be made as frequently as in Landlord's opinion appears appropriate
in order to facilitate an



                                      -16-


<PAGE>   19
equitable apportionment of any Operating Expenses which are incurred on a
Building or Project basis, as applicable; provided, however, that remeasurement
of the Project and review of allocations shall be made upon any increase or
decrease of the area of the Project. Such review shall be performed by the
Project Architect or by another licensed architect selected by Landlord, and,
after consultation with Tenant and certification as correct by such licensed
architect, the parties shall be bound by such certifications; provided, however,
that in the event Tenant contests the conclusion of such licensed architect,
Tenant shall have the right, at Tenant's sole cost and expense, to retain a
licensed architect to remeasure the Building or the Project. If the conclusions
of the architect retained by Tenant differ from the conclusions of the architect
retained by Landlord by more than two percent 2% of the total square footage of
the Project or the Building, the architects shall consult and agree on the
measurement of the Project and Landlord and Tenant shall be bound by such agreed
to measurement.

8.       Security Deposit

         8.1. Tenant shall deposit with Landlord on or before the date Landlord
commences construction of the Tenant Improvements, the Security Deposit, which
Security Deposit shall be held by Landlord as security for the performance by
Tenant of all of the terms, covenants and conditions of this Lease to be kept
and performed by Tenant during the Term.

              8.1.1. [Intentionally deleted]

              8.1.2. In the event the rentable square footage of the Demised
Premises is increased or the Tenant Improvement Allowance is increased, upon
Tenant's receipt of written notice of such determination from Landlord Tenant
shall deposit an additional sum reflecting the increased Monthly Rental
Installment and the Improvement Rent with the Landlord in order to cause the
amount then held by Landlord to equal three times the sum of (i) the Monthly
Rental Installment, plus (ii) three monthly payments of Improvement Rent, which
amount shall be added to and treated as a part of the Security Deposit.

         8.2. The Security Deposit may be delivered either in cash or in a form
of letter of credit reasonably acceptable to Landlord.

              8.2.1. If Tenant elects a cash deposit, the Security Deposit shall
be held in a separate, non-commingled interest bearing account at the direction
of Landlord. The interest on the Security Deposit shall inure to the benefit of
Tenant and shall be paid out on the same schedule as such interest is paid out
to Landlord.

              8.2.2. In lieu of depositing cash as the Security Deposit, Tenant
shall have the right to deliver to Landlord an unconditional, irrevocable
standby letter of credit in the amount of the cash Security Deposit otherwise
required hereunder, which letter of credit shall (i) be in a form reasonably
acceptable to Landlord, (ii) be issued by a financial institution selected by
Tenant and reasonably acceptable to Landlord, (iii) be for the benefit of
Landlord, but shall be



                                      -17-


<PAGE>   20
assignable by Landlord to any subsequent purchaser or encumbrancer of the
Building or the Project, (iv) be automatically renewable from year to year
throughout the Term, (v) be payable by draft sight in a location reasonably
acceptable to Landlord upon presentation of a certification signed by an officer
of Landlord which states that a default under the Lease has occurred and has not
been cured within any applicable cure period, and (vi) be payable in the event
such letter of credit is not renewed on or before the date which is thirty (30)
days prior to its expiration. Any amounts of cash drawn on a letter of credit
Security Deposit will thereafter be treated as a cash Security Deposit
hereunder.

              8.2.3. Tenant shall have the right at any time during the Term
upon thirty (30) days prior written notice to Landlord (i) to replace a cash
Security Deposit with a letter of credit which complies with all of the terms of
Section 8.2.2, or (ii) to replace a letter of credit Security Deposit with an
applicable amount of cash.

         8.3. If a Default has occurred with respect to any provision of this
Lease, including but not limited to any provision relating to the payment of
Rent, Landlord may (but shall not be required to) use, apply, or retain all or
any part of the Security Deposit for the payment of any Rent or any other sum in
default, or to compensate Landlord for any other loss or damage which Landlord
may suffer by reason of Tenant's default. If any portion of the Security Deposit
is so used or applied, Tenant shall, upon demand therefor, deposit cash or a
replacement letter of credit with Landlord in an amount sufficient to restore
the Security Deposit to the amount required to have been on deposit with
Landlord immediately preceding any use, application or retainment by Landlord,
and Tenant's failure to do so shall constitute a material breach of this Lease.

         8.4. In the event of bankruptcy or other debtor-creditor proceedings
against Tenant, the Security Deposit shall be deemed to be applied first to the
payment of Rent and other charges due Landlord for all periods prior to the
filing of such proceedings.

         8.5. Landlord shall deliver the unused portion of the Security Deposit
by Tenant to any purchaser of Landlord's interest in the Demised Premises and
thereupon such purchaser shall assume this Lease pursuant to an instrument
naming Tenant as a third-party beneficiary thereof and Landlord shall be
discharged from any further liability with respect to such Security Deposit.
This provision shall also apply to any subsequent transfers.

         8.6. So long as no default by Tenant has occurred and is continuing the
Security Deposit, or, in the event of a cash Security Deposit, any balance
thereof together with any interest thereon not yet paid to Tenant pursuant to
Section 8.2.1, shall be returned to Tenant (or, at Landlord's option, to the
last assignee of Tenant's interest hereunder) within ninety (90) days after the
expiration or earlier termination of this Lease. In the event that Tenant is in
default on the date of the expiration or earlier termination of this Lease,
Landlord shall within a reasonable time return to Tenant the balance of the
Security Deposit, if any, after Landlord,



                                      -18-


<PAGE>   21
pursuant to Section 8.3, has applied the Security Deposit with respect to any
default. The obligations under this Section 8.6 shall survive the expiration or
termination hereof.

9.       Right of First Offer to Lease Additional Space.

         Tenant shall have the right, but not the obligation, to expand the
Demised Premises (the "Expansion Right") to include the Expansion Space upon the
following terms and conditions:

         9.1. In the event that Landlord desires to lease all or any portion of
the Expansion Space, Landlord shall deliver to Tenant written notice (the
"Expansion Notice") of the availability of such portion of the Expansion Space,
together with the terms and conditions on which Landlord is prepared to lease to
Tenant such portion of the Expansion Space. Tenant shall have ten (10) days
following delivery of the Expansion Notice to deliver to Landlord written
notification of Tenant's exercise of the Expansion Right and agreement to lease
such portion of the Expansion Space upon the terms and conditions of the
Expansion Notice. In the event Tenant fails to timely deliver such notice, or if
Landlord and Tenant are unable to agree upon any of the terms of the lease
agreement for such portion of the Expansion Space after negotiating in good
faith, Tenant shall be deemed to have waived any right to lease such portion of
the Expansion Space unless and until such portion of the Expansion Space again
becomes vacant following a tenancy, or, if such portion of the Expansion Space
is not thereafter leased by Landlord, following the date which is one hundred
eighty (180) days following the date of delivery of the Expansion Notice for
such Expansion Space.

         9.2. Within ten (10) days after the proper exercise of the Expansion
Right, Tenant and Landlord shall enter into a written amendment to the Lease
(the "Expansion Amendment") which shall provide, unless otherwise agreed in
writing, (a) the commencement date of the Expansion Space; (b) that the Demised
Premises under this Lease shall be increased to include the rentable square feet
of the Expansion Space; (c) the new Annual Base Rent; (d) Tenant's new Pro Rata
Share of Building Operating Expenses and Tenant's new Pro Rata Share of Project
Operating Expenses, each based upon the addition of the Expansion Space to the
Demised Premises; (e) the proportionate increase to the Security Deposit (which
shall be payable upon execution of the Expansion Amendment). In all other
respects, this Lease shall remain in full force and effect, and shall apply to
the Expansion Space.

         9.3. Notwithstanding the above, the Expansion Right shall not be in
effect and may not be exercised by Tenant:

              9.3.1. during the period starting on the date hereof and ending
one hundred eighty (180) days thereafter;

              9.3.2. during any period of time that Tenant is in Default under
any provision of the Lease; or



                                      -19-


<PAGE>   22
              9.3.3. if Tenant has been in Default under any provision of the
Lease three (3) or more times, whether or not the defaults are cured, during the
five (5) month period prior to the date on which Tenant seeks to exercise the
Expansion Right.

         9.4. The period of time within which any Expansion Right may be
exercised shall not be extended or enlarged by reason of the Tenant's inability
to exercise the Expansion Right because of the provisions of Section 9.3 above.

         9.5. The Expansion Right shall terminate and be of no further force or
effect even after Tenant's due and timely exercise of the Expansion Right, if,
after such exercise, but prior to the commencement date of the Expansion Space,
(1) Tenant fails to timely cure any default by Tenant under the Lease; or (2)
Tenant has defaulted three (3) or more times during the period from the date of
the exercise of the Expansion Right to the date of the commencement of the
Expansion Space, whether or not such defaults are cured.

         9.6. The Expansion Right is not assignable separate and apart from this
Lease.

10.      Use

         10.1. Tenant shall use the Demised Premises for the purpose set forth
in Section 2.1.10 and shall not use the Demised Premises, or permit or suffer
the Demised Premises to be used, for any other purpose without the prior written
consent of Landlord which shall not be unreasonably withheld, conditioned or
delayed.

         10.2. Tenant shall not use or occupy the Demised Premises in violation
of any federal, state, and local laws and regulations, zoning ordinances, or of
the certificate of occupancy issued for the Building, and shall, upon five (5)
days written notice from Landlord, discontinue any use of the Demised Premises
which is declared or claimed by any governmental authority having jurisdiction
to be a violation of law, regulation, zoning ordinance, or the certificate of
occupancy, or which in the reasonable opinion of Landlord threatens human life
and safety. Tenant shall comply with any direction of any governmental authority
having jurisdiction which shall, by reason of the nature of Tenant's use or
occupancy of the Demised Premises, impose any duty upon Tenant or Landlord with
respect to the Demised Premises or with respect to the use or occupation
thereof; provided, however, that Tenant shall have the right, at Tenant's sole
cost and expense, to contest any such ruling, order or direction of any
governmental authority, so long as Tenant shall, at its sole expense, defend and
protect itself, Landlord and the Demised Premises against the same and shall pay
and satisfy any such adverse judgment that may be rendered thereon before the
enforcement thereof against the Landlord or the Demised Premises. If Landlord
shall require, Tenant shall furnish to Landlord a letter of credit or surety
bond in a form reasonably satisfactory to Landlord and in an amount reasonably
requested by Landlord, indemnifying Landlord against liability for Tenant's
noncompliance, and, so long as such noncompliance by Tenant does not affect
human



                                      -20-


<PAGE>   23
life or safety. So long as Tenant continues to contest such ruling, order or
direction diligently and in good faith, Tenant's noncompliance shall not be a
default hereunder.

         10.3. Tenant shall not do or permit to be done anything which will
invalidate any fire, environmental, extended coverage or any other insurance
policy covering the Building and Project, and Tenant shall comply with all
rules, orders, regulations, and requirements of the insurers of the Building and
Project. In the event Tenant's activities in the Building or Project increase
the cost of any insurance policy covering the Building or the Project, upon
Landlord's demand, Tenant shall promptly reimburse Landlord for any additional
premium charged for such policy.

         10.4. Tenant shall not do or permit anything to be done in or about the
Demised Premises which shall in any way obstruct or interfere with the rights of
or injure other tenants or occupants of the Project.

         10.5. Tenant shall not use or allow the Demised Premises to be used for
immoral or unlawful purposes.

         10.6. Tenant shall not knowingly cause, maintain, or permit any
nuisance or waste in, on, or about the Demised Premises, the Building, or the
Project.

         10.7. [Intentionally omitted]

         10.8. No additional locks or bolts of any kind shall be placed upon any
of the doors or windows by Tenant nor shall any changes be made in existing
locks or the mechanism thereof without the prior written consent of Landlord
(or, alternatively, without furnishing to Landlord at least two master keys
therefor). Tenant must, upon termination of this Lease, return to Landlord all
keys to offices and restrooms, either furnished to or otherwise procured by
Tenant. In the event any such key is lost, Tenant shall pay to Landlord the cost
of replacing the same or of changing the lock(s) opened by such lost key if
Landlord shall deem it necessary to make such change. Notwithstanding the
foregoing, Tenant shall have the right to designate certain areas of the
Building as "secure" areas, and, subject to the provisions of Section 30.3, to
limit access thereto.

         10.9. Unless and until Tenant shall have received the express written
consent of Landlord, which shall not be unreasonably withheld, conditioned or
delayed (i) no awnings or other projection shall be attached to any outside wall
of the building; (ii) no curtains, blinds, shades or screens shall be attached
to, hung in, or used in connection with any window or door of the Demised
Premises other than Landlord's standard window coverings; (iii) neither the
interior nor exterior of any windows shall be coated or otherwise sunscreened,
nor shall any bottles, parcels, or other articles be placed on the window sills;
and (iv) no equipment, furniture or other items of personal property shall be
placed on any exterior balcony.



                                      -21-


<PAGE>   24
         10.10. No sign, advertisement, or notice shall be exhibited, painted or
affixed by Tenant on any part of the Demised Premises or the Building without
the prior written consent of Landlord.

         10.11. Tenant shall cause any office equipment or machinery to be
installed in the Demised Premises so as to reasonably prevent sounds or
vibrations therefrom from extending into the Project Common Areas, or other
space in the Project. Further, no equipment weighing five hundred (500) pounds,
or greater, shall be placed upon the Demised Premises without advance notice to
and approval by Landlord, which approval shall not be unreasonably withheld,
conditioned or delayed. Placement of any equipment, if approved by Landlord,
shall be at a location designed to carry the weight of such equipment.

         10.12. Other than costs which shall be included in Operating Expenses
pursuant to Section 6 associated with causing the Demised Premises to comply
with any retroactively effective law, code, rule or regulation where
noncompliance does not result from any use of or alterations to the Demised
Premises by Tenant, Tenant shall be responsible for all liabilities, costs and
expense arising out of or in connection with the compliance of the Demised
Premises with the ADA and Tenant shall indemnify, defend, and hold harmless from
and against any loss, cost, liability, or expense (including reasonable
attorneys fees and disbursements) arising out of any failure of the Demised
Premises to comply with the ADA.

11.      Brokers

         11.1. Tenant represents and warrants that it has had no dealings with
any real estate broker or agent in connection with the negotiation of this Lease
other than Smithy Braedon, OnCor International and Randall H. Hagner Company
(collectively the "Brokers"). Landlord represents and warrants that it has had
no dealings with any real estate broker or agent in connection with the
negotiation of this Lease other than the Brokers.

         11.2. Tenant hereby indemnifies and agrees to defend, hold, and save
Landlord harmless from and against any and all claims for any commission or fees
in connection with this Lease made by any broker or finder having worked, or
claiming to have worked, on behalf of Tenant, other than Brokers. Landlord
hereby indemnifies and agrees to defend, hold, and save Tenant harmless from and
against any and all claims for any commission or fees in connection with this
Lease made by any broker or finder having worked, or claiming to have worked, on
behalf of Landlord, other than Brokers. The indemnifications of this Section
11.2 shall survive the termination of this Lease.

         11.3. All commissions and fees owing to Brokers in connection with this
Lease shall be paid by Landlord in accordance with a separate agreement.
Landlord hereby indemnifies and agrees to defend, hold and save Tenant harmless
from and against any and all claims for any commission or fees in connection
with this Lease made by any broker or finder having worked, or claiming to have
worked, on behalf of Landlord, including Brokers. The



                                      -22-


<PAGE>   25
obligations under this Section 11.3 shall survive the expiration or earlier
termination of this Lease.

         11.4. Tenant represents and warrants that no broker or agent has made
any representation or warranty relied upon by Tenant in Tenant's decision to
enter into this Lease other than as contained in this Lease.

         11.5. Tenant acknowledges and agrees that the employment of brokers by
Landlord is for the purpose of solicitation of offers of lease from prospective
tenants and no authority is granted to any broker to furnish any representation
(written or oral) or warranty from Landlord unless expressly contained within
this Lease. Landlord, in executing this Lease, does so in reliance upon Tenant's
representations and warranties contained within Article 11.

12.      Holding Over

         12.1. If, with Landlord's express written consent, Tenant holds
possession of all or any part of the Demised Premises after the expiration or
earlier termination of the Term, Tenant shall become a tenant from
month-to-month upon the date of such expiration or earlier termination, and in
such case Tenant shall continue to pay Rent in the amount of 125% of the Rent
payable upon the date of the expiration or earlier termination of this Lease,
and all other provisions, representations, covenants, and agreements contained
herein, other than with respect to the Term and any extension thereof, but
specifically including, without limitation, the adjustment of the Annual Base
Rent and Improvement Rent pursuant to Article 5, shall remain in full force and
effect.

         12.2. Notwithstanding the foregoing, if Tenant remains in possession of
the Demised Premises after the expiration or earlier termination of the Term
without the express written consent of Landlord, Tenant shall become a tenant at
sufferance upon the terms of this Lease except that the monthly rental shall be
equal to two hundred percent (200%) of the Rent in effect during the last thirty
(30) days of the Term and Tenant shall be responsible for any and all damages
which Landlord may suffer as a result of Tenant's holding over.

         12.3. Acceptance by Landlord of Rent after such expiration or earlier
termination of the Term shall not result in a renewal or reinstatement of this
Lease.

         12.4. The foregoing provisions of this Article 12 are in addition to
and do not affect Landlord's right to re-entry or any other rights of Landlord
hereunder or as otherwise provided by law.



                                      -23-


<PAGE>   26
13.      Taxes on Tenant's Property

         13.1. Prior to delinquency, Tenant shall pay directly to the assessing
entity any and all taxes levied against any personal property or trade fixtures
placed by Tenant in or about the Demised Premises.

         13.2. If any taxes on Tenant's personal property or trade fixtures are
levied against Landlord or Landlord's property or, if the assessed valuation of
the Building is increased by the inclusion therein of a value attributable to
Tenant's personal property or trade fixtures, and if Landlord, after written
notice to Tenant, pays such taxes, then Tenant shall upon demand repay to
Landlord the taxes so levied against Landlord.

         13.3. [Intentionally omitted.]

14.      Project Common Areas, Parking Facilities.

         14.1. Tenant shall have the non-exclusive right, in common with others,
to use the Project Common Areas, subject to the Rules and Regulations.

         14.2. As an appurtenance to the Demised Premises, Tenant shall have (i)
the exclusive right to use the parking facilities on the Land; and (ii) a
non-exclusive revocable license to use parking facilities within the Project on
a non-reserved basis up to a maximum ratio equal to not more than (x) three (3)
spaces per 1,000 square feet of rentable administration, research and
development area in the Building, and (y) two (2) spaces per 1,000 square feet
of rentable manufacturing and warehouse area in the Building. Landlord shall not
assign more parking rights to tenants of the Project than the number of parking
spaces that actually exist in the Project Common Areas.

         14.3. Landlord reserves the right to modify the Project Common Areas
(including the right to add or remove exterior and interior landscaping). Any
such modification shall not deny Tenant access to the Building or the Land for
the uses contemplated in this Lease.

15.      Utilities and Services

         15.1. Tenant shall pay for all water, (including the cost to service,
repair and replace reverse osmosis, deionized and other treated water) gas,
heat, light, power, telephone and other utilities supplied to the Demised
Premises, together with any fees, surcharges, and taxes thereon. All such
utilities shall be separately metered to Tenant.

         15.2. Landlord shall not be liable for nor shall any constructive
eviction of Tenant result from the failure to furnish any services or any such
utilities whether or not such failure is caused by accident, breakage, repairs,
strikes, lockouts or other labor disturbances or labor disputes of any
character, governmental regulation, moratorium or other governmental action,



                                      -24-


<PAGE>   27
inability despite the exercise of reasonable diligence or by any other cause,
including the negligence of Landlord. In the event of such failure, Tenant shall
not be entitled to any abatement or reduction of Rent, nor be relieved from the
operation of any covenant or agreement of this Lease. In the event such failure
persists for an unreasonable time after notice from Tenant to Landlord, Tenant
may, at its cost, cause such utilities or services to be performed or provided.

         15.3. Tenant shall pay directly to the applicable utility or service
provider, prior to delinquency, for any separately metered utilities and
services which may be furnished to Tenant or the Demised Premises during the
Term.

         15.4. Tenant shall not, without the prior written consent of Landlord,
use any device in the Demised Premises, including, but without limitation, data
processing machines, which will in any way increase the amount of ventilation,
air exchange, gas, steam, electricity or water beyond the existing capacity of
the Building systems.

         15.5. [Intentionally omitted.]

         15.6. [Intentionally omitted.]

         15.7. Landlord reserves the right to stop service of the elevator,
plumbing, ventilation, air conditioning, and electric systems at any time when
necessary by reason of accident or emergency or otherwise in a reasonable manner
least disruptive to Tenant's business operations and upon notice to and approval
by Tenant, which approval shall not be unreasonably withheld, conditioned or
delayed, for repairs, alterations, or improvements, in the judgment of Landlord
desirable or necessary to be made, until said repairs, alterations, or
improvements shall have been completed. Landlord shall further have no
responsibility or liability (A) for failure to supply elevator facilities,
plumbing, ventilation, air conditioning or electric service when prevented from
doing so (i) by strike or accident, or (ii) by laws, rules, order, ordinances,
directions, regulations or requirements of any federal, state, country or
municipal authority, or (B) for failure to deliver gas, oil or other suitable
fuel supply or inability by exercise of reasonable diligence to obtain gas, oil
or other suitable fuel. It is expressly understood and agreed that any covenants
on Landlord's part to furnish any service pursuant to any of the terms,
covenants, conditions, provisions or agreements of this Lease, or to perform any
act or thing for the benefit of Tenant, shall not be deemed breached if Landlord
is unable to furnish or perform the same by virtue of a Force-Majeure Delay.

         15.8. Tenant shall have the right, at Tenant's sole cost and expense,
upon not less than ninety (90) days advance written notice to Landlord, to
contract directly with third parties for the following services to the Demised
Premises: cleaning, security guards and electronic surveillance, maintenance and
repair of HVAC and electrical systems, fire protection and trash removal. In the
event that Landlord has previously approved a direct contract for any of the
services listed in the preceding sentence and Tenant desires to change the
contractor providing



                                      -25-


<PAGE>   28
such service, Tenant shall deliver written notice to Landlord not less than
seven (7) Business Days prior to the date Tenant intends to change such
contractor. Notwithstanding anything to the contrary set forth herein, Landlord
shall have the right to review and approve, in Landlord's reasonable discretion,
all service contracts entered into by Tenant pursuant to this Section 15.8, and
Landlord shall have the right to enforce the standards of such service contracts
and to terminate and replace such service contracts if, in Landlord's reasonable
discretion, such services are not being provided in a manner consistent with
this Lease.

16.      Alterations

         16.1. Other than Tenant's Work and subject to the provisions of Section
16.10, Tenant shall make no alterations, additions or improvements in or to the
Demised Premises without Landlord's prior written consent, which approval shall
not be unreasonably withheld (provided, however, that in the event any proposed
alteration, addition or improvement affects (i) any structural portions of the
Building including exterior walls, roof, foundation and core of the Building, or
(ii) the exterior of the Building, then Landlord may withhold its consent with
respect thereto in its sole and absolute discretion), and then only by
architects, contractors, suppliers or mechanics approved by Landlord. In seeking
Landlord's approval, Tenant shall provide Landlord, at least fourteen (14) days
in advance of any proposed construction, with plans, specifications, bid
proposals, work contracts and such other information concerning the nature and
cost of the alterations as may be reasonably requested by Landlord, including,
without limitation, a completion and lien indemnity bond secured by Tenant at
Tenant's own cost and expense.

         16.2. Tenant agrees that there shall be no construction of partitions
or other obstructions which interferes with free access to mechanical
installation or service facilities of the Building or interfere with the moving
of Landlord's equipment to or from the enclosures containing said installations
or facilities.

         16.3. Tenant agrees that any work by Tenant shall be accomplished in
such a manner as to permit any fire sprinkler system and fire water supply lines
to remain fully operable at all times.

         16.4. Tenant covenants and agrees that all work done by Tenant shall be
performed in full compliance with all laws, rules, orders, ordinances,
directions, regulations, and requirements of all governmental agencies, offices,
departments, bureaus and boards having jurisdiction, and in full compliance with
the rules, orders, directions, regulations, and requirements of any applicable
fire rating bureau. Tenant shall provide Landlord with "as-built" plans showing
any change in the Demised Premises.

         16.5. All alterations, attached equipment, decorations, fixtures, trade
fixtures, additions and improvements, subject to Section 16.1 and Section 16.7,
attached to or built into the Demised Premises, made by either Landlord or
Tenant, including (without limiting the



                                      -26-


<PAGE>   29
generality of the foregoing) all floor and wallcovering, built-in cabinet work
and paneling, sinks and related plumbing fixtures, exterior venting fume hoods,
walk-in freezers and refrigerators, clean rooms, climatized rooms, ductwork,
conduits, and electrical panels and circuits shall become the property of
Landlord upon the expiration or earlier termination of the term of this Lease
and further shall remain upon and be surrendered with the Demised Premises as a
part thereof.

         16.6. At the same time as Landlord delivers to Tenant Landlord's
consent to any alteration, addition or improvement pursuant to Section 16.1,
Landlord shall notify Tenant of Landlord's election to cause Tenant to remove
any items which are the subject of such consent from the Demised Premises upon
the expiration or earlier termination of this Lease. If Landlord elects that
Tenant shall remove any item, Tenant shall remove such item upon the expiration
or earlier termination of this Lease, and Tenant shall repair any damage to the
Demised Premises, including damage caused by or occasioned as a result of
removals requested by Landlord. During any such restoration period, Tenant shall
pay Rent to Landlord as provided herein as if said space were otherwise occupied
by Tenant.

         16.7. Except as to those items listed on Exhibit "G" attached hereto
and incorporated herein, as may be amended from time to time and approved in
writing by both parties hereto (together with Tenant's personal property and
items which Landlord elects to cause Tenant to remove pursuant to Section 16.6,
"Tenant's Property"), all business and trade fixtures, machinery and equipment,
built-in furniture and cabinets, together with all additions and accessories
thereto, installed in and upon the Demised Premises shall be and remain the
property of Landlord and shall not be moved by Tenant at any time during the
Term. If Tenant shall fail to remove all of Tenant's Property from the Demised
Premises prior to termination of this Lease, then Landlord may, at its option,
remove the same in any manner that Landlord shall choose, and store all such
items without liability to Tenant for loss thereof or damage thereto, and Tenant
agrees to pay Landlord upon demand any expenses incurred in connection with such
removal and storage. Landlord may, at its option, without notice, sell such
property or any of the same, at private sale and without legal process, for such
price as Landlord may obtain and apply the proceeds of such sale against any
amounts due under this Lease from Tenant to Landlord and against any expenses
incident to the removal, storage and sale of such property. Notwithstanding
anything to the contrary set forth elsewhere in this Lease, (a) Tenant shall
have the right to remove emergency power generation systems, autoclaves, fume
hoods that are not exterior venting, modular cold rooms, robotics equipment,
modular office type furniture, phone systems, film processors and other Tenant
equipment; provided, however, that Tenant shall repair any damage caused by the
removal thereof and (b) Tenant shall not have the right to remove piping,
ductwork, exhaust vents, wiring, cabling, electrical panels, transfer switches,
transformers, circuits, conduits, gas and vacuum distribution systems, reverse
osmosis and deionized water systems, exterior exhausting fume hoods, built-in
casework, built-in bench tops, built-in cabinets, wall and floor coverings,
pumps, Building boilers, air-handlers, steam coils, heat exchangers, chillers,
waste disposal systems, steam generators, light fixtures, life and safety
systems (i.e., security and fire alarms,



                                      -27-


<PAGE>   30
eye wash stations and fire sprinklers), drop ceiling structure and tiles, sinks
and hot water heaters. In any event Tenant shall not be permitted to remove (i)
any part of the Building's systems, (ii) anything purchased or paid for by
Landlord directly or through the payment by Landlord to Tenant of any
construction or improvement allowance, or (iii) anything that could result in
significant damage to the Building. If Tenant shall fail to remove all of its
effects from the Demised Premises prior to termination of this Lease, then
Landlord may, at its option, remove the same in any manner than Landlord shall
choose, and store said effects without liability to Tenant for loss thereof or
damage thereto, and Tenant agrees to pay Landlord upon demand any expenses
incurred to such removal and storage or Landlord may, at its option, without
notice, sell said property or any of the same, at private sale and without legal
process, for such price as Landlord may obtain and apply the proceeds of such
sale against any amounts due under this Lease from Tenant to Landlord and
against any expenses incident to the removal, storage and sale of said personal
property.

         16.8. Notwithstanding any other provision of this Article 16 to the
contrary, in no event may Tenant remove any improvement from the Demised
Premises as to which Landlord contributed payment, including, without
limitation, the Tenant Improvements made pursuant to the Work Letter without
Landlord's prior written consent, which may be withheld in Landlord's sole
discretion.

         16.9. In connection with any alteration, addition or improvement made
by Tenant pursuant to the terms of this Section 16, the cost of which is less
than or equal to $250,000, Tenant shall reimburse Landlord for all of Landlord's
reasonable out-of-pocket costs and expenses related to Landlord's review and
approval of the plans for and work related to such alteration, addition or
improvement ("Landlord's Review Costs"). In connection with any alteration,
addition or improvement made by Tenant pursuant to the terms of this Section 16,
the cost of which is in excess of $250,000, Tenant shall pay to Landlord an
amount (the "Excess Review Cost") equal to (i) Landlord's Review Costs, plus
(ii) an amount equal to 2.5% of the difference between $250,000 and the actual
cost of such addition, alteration or improvement as evidenced by copies of all
bills, invoices and statements regarding such work; provided that the Excess
Review Cost shall in no event exceed $25,000. Tenant shall reimburse Landlord
for any extra expense incurred by Landlord by reason of faulty work done by
Tenant or its contractors, or by reason of delays caused by such work, or by
reason of inadequate cleanup. The provisions of this Section 16.9 shall not
apply in the event of an expansion of the Demised Premises not otherwise
contemplated by this Lease.

         16.10. Right to Expand Building. Subject to any and all requirements of
applicable law or as hereinafter provided, Tenant shall have the right, all at
Tenant's sole cost and expense, to expand the Building up to a total Rentable
Area of one hundred twenty thousand one hundred (120,100) square feet (the
"Building Expansion"). Notwithstanding anything to the contrary set forth
herein, Landlord shall have the right to review and approve all design and
construction plans for such Building Expansion, which consent, so long as such
plans reflect a Building Expansion of a design consistent with the current
design of the Building and



                                      -28-


<PAGE>   31
construction quality of the same or better quality than the Building, shall not
be unreasonably withheld. The Building Expansion shall be performed and
completed only by architects, contractors, suppliers or mechanics previously
used in the construction of the Building or the Tenant Improvements or as
reasonably



                                      -29-


<PAGE>   32
approved by Landlord. In seeking Landlord's approval of the Building Expansion
plans, Tenant shall provide Landlord, at least forty-five (45) days in advance
of any proposed construction, with plans, specifications, bid proposals, work
contracts and such other information concerning the nature of the alterations as
may be reasonably requested by Landlord, including, without limitation, a
completion and lien indemnity bond secured by Tenant at Tenant's own cost and
expense or such other security as Landlord may require. Except as specifically
provided in this Section 16.10 to the contrary, all of the provisions of this
Article 16 shall apply to the Building Expansion and the construction of any
improvements related thereto. Notwithstanding anything to the contrary set forth
herein, Annual Base Rent and Improvement Rent shall not increase as a result of
any Building Expansion completed pursuant to the terms of this Section 16.10,
but Rentable Area of the Building shall increase for all other purposes under
this Lease to the Rentable Area established by a remeasurement of the Building
following completion of the Building Expansion, which remeasurement shall be
conducted in the same manner as set forth in Section 7.3. Nothing in this
Section 16.10 or in this Lease shall be construed to obligate Landlord to, and
Landlord shall have no obligation to, expend any monies or incur any costs in
connection with or as a result of the Building Expansion.

17.      Repairs and Maintenance

         17.1. Landlord shall repair and maintain the Project Common Areas,
including, without limitation, repair and maintenance of landscaping, parking
facilities, driveways, walkways, lighting, utilities, snow removal, irrigation
and storm water management systems (and the full cost thereof shall be included
as a part of Operating Expenses), unless such maintenance or repairs are
required in whole or in part because of any act, neglect, fault of or omissions
of any duty by Tenant, its agents, servants, employees or invitees, in which
case Tenant shall pay to Landlord the cost of such maintenance and repairs.

         17.2. Except for services of Landlord, if any, required by Section
17.1, Tenant shall at Tenant's sole cost and expense keep the Demised Premises
and every part thereof in good condition and repair, damage thereto from
ordinary wear and tear and condemnation excepted. Tenant shall, upon the
expiration or earlier termination of the Term, surrender the Demised Premises to
Landlord in as good as condition as when received, condemnation and ordinary
wear and tear excepted. Other than as specifically set forth in the Work Letter,
Landlord shall have no obligation to alter, remodel, improve, repair, decorate,
or paint the Demised Premises or any part thereof.

         17.3. [Intentionally Omitted.]

         17.4. Tenant shall at all times during the Term maintain and operate
the Building in a first-class manner for the uses set forth in Section 2.1.10.
Landlord shall at all times during the Term maintain and operate the Project in
a first-class manner for (i) pharmaceutical,



                                      -30-


<PAGE>   33
biological or medical device research laboratory uses and related manufacturing,
warehouse and distribution uses, or (ii) first-class office uses.

         17.5. This Article 17 relates to repairs and maintenance arising in the
ordinary course of operation of the Building, the Project and any related
facilities. In the event of fire, earthquake, flood, war, or similar cause of
damage or destruction, this Article 17 shall not be applicable and the
provisions of Article 21 entitled "Damage or Destruction" shall apply and
control.

18.      Liens

         18.1. Subject to the immediately succeeding sentence, Tenant shall keep
the Demised Premises, the Building, the Project and the real property upon which
the Building and the Project are situated free from any liens arising out of
work performed, materials furnished or obligations incurred by Tenant. Tenant
further covenants and agrees that any mechanic's lien filed against the Demised
Premises or against the Building or the Project for work claimed to have been
done for, or materials claimed to have been furnished to Tenant, will be
discharged by Tenant, by bond or otherwise, within fifteen (15) days after the
filing thereof, at the sole cost and expense of Tenant.

         18.2. Should Tenant fail to discharge any lien of the nature described
in Section 21.1, Landlord may at Landlord's election pay such claim or post a
bond or otherwise provide security to eliminate the lien as a claim against
title and the cost thereof shall be immediately due from Tenant as Additional
Rent.

         18.3. In the event Tenant shall lease or finance the acquisition of
office equipment, furnishings, or other personal property which are or, if
acquired by Tenant, would be Tenant's Property, Tenant warrants that any Uniform
Commercial Code Financing Statement executed by Tenant will upon its face or by
exhibit thereto indicate that such Financing Statement is applicable only to
such Tenant's Property located within the Demised Premises. In no event shall
the address of the Building be furnished on the statement without qualifying
language as to applicability of the lien only to such Tenant's Property, located
in an identified suite held by Tenant. Should any holder of a Financing
Statement executed by Tenant record or place of record a Financing Statement
which appears to constitute a lien against any interest of Landlord or against
equipment which may be located other than within the Demised Premises, Tenant
shall within ten (10) days after filing such Financing Statement cause (i) a
copy of the Security Agreement or other documents to which Financing Statement
pertains to be furnished to Landlord to facilitate Landlord's being in a
position to show such lien is not applicable to Landlord's interest, and (ii)
cause Tenant's lender to amend any documents of record so as to clarify that
such lien is not applicable to any interest of Landlord in the Building or the
Project.

19.      Indemnification and Exculpation



                                      -31-


<PAGE>   34
         19.1. Tenant hereby indemnifies and agrees to defend, hold and save
Landlord harmless from and against any and all demands, claims, liabilities,
losses, costs, expenses, actions, causes of action, damages or judgments, and
all reasonable expenses incurred in investigating or resisting the same
(including, without limitation, reasonable attorneys' fees, charges and
disbursements), for injury or death to Person or injury to property occurring
within or about the Demised Premises, arising out of the use or occupancy of the
Demised Premises by Tenant and its employees, agents, or guests or a breach or
default by Tenant in the performance of any of its obligations hereunder, unless
caused solely by the willful act or negligence of Landlord. The obligations
under this Section shall survive the expiration or termination of this Lease.

         19.2. Landlord hereby indemnifies and agrees to defend, hold and save
Tenant harmless from and against any and all demands, claims, liabilities,
losses, costs, expenses, actions, causes of action, damages or judgments, and
all reasonable expenses incurred in investigating or resisting the same
(including, without limitation, reasonable attorneys' fees, charges and
disbursements), for injury or death to Person or injury to property occurring
within or about the Project, arising out of the use or occupancy of the Project
by Landlord and its employees, agents, or guests or a breach or default by
Landlord in the performance of any of its obligations hereunder, unless caused
solely by the willful act or negligence of Tenant. The obligations under this
Section shall survive the expiration or termination of this Lease.

         19.3. Landlord shall not be liable to Tenant and Tenant assumes all
risk of damage to personal property or scientific research, including loss of
records kept within the Demised Premises if the cause of such damage is of a
nature which, if Tenant had elected to maintain fire and theft insurance with
extended coverage and business records endorsement available on a commercially
reasonable basis, would be a loss subject to settlement by the insurance
carrier, including, but not limited to, damage or losses caused by fire,
electrical malfunctions, gas explosion, and water damage of any type, including,
but not limited to, broken water lines, malfunction of fire sprinkler system,
roof leakage or stoppages of lines unless and except if such loss is due to
willful disregard of Landlord after written notice by Tenant of need for a
repair which Landlord is responsible to make for an unreasonable period of time.
Tenant further waives any claim for injury to Tenant's business or loss of
income relating to any such damage or destruction of personal property including
any loss of records.

         19.4. Landlord shall not be liable for any damages arising from any
act, omission or neglect of any other tenant in the Building or the Project or
of any other third party other than an agent, contractor or employee of
Landlord.

         19.5. Security devices and services, if any, while intended to deter
crime may not in given instances prevent theft or other criminal acts. Tenant
agrees that Landlord shall not be liable for injuries or losses caused by
criminal acts of third parties, and Tenant assumes the risk that a criminal may
circumvent any security device or service or that a security device or service
may malfunction. Tenant shall, at Tenant's cost, obtain insurance coverage to
the



                                      -32-


<PAGE>   35
extent Tenant desires protection against such criminal acts. Tenant shall have
the right, subject to Landlord's reasonable approval of the aesthetic impact of
such measures on the Building and the Project, to install security gates or
other security devices at and around the Building; provided, however, that
Landlord and public life and safety agencies shall at all times have access to
the Building, subject to "secure" areas pursuant to Section 10.8.

20.      Insurance - Waiver of Subrogation

         20.1. Landlord, as part of Operating Expenses, shall carry insurance
upon the Building (including the Tenant Improvements), in an amount equal to
full replacement cost (exclusive of the costs of excavation, foundations, and
footings, and without reference to depreciation taken by Landlord upon its books
or tax returns) or such lesser coverage as Landlord may elect provided such
coverage is not less than ninety percent (90%) of such full replacement cost or
the amount of such insurance Landlord's mortgage lender requires Landlord to
maintain, providing protection against any peril generally included within the
classification "Fire and Extended Coverage" together with insurance against
sprinkler damage (if applicable), vandalism and malicious mischief.

         20.2. Landlord, subject to availability thereof and as part of
Operating Expenses, shall further insure, as Landlord deems appropriate,
coverage against flood, environmental hazard and earthquake, loss or failure of
building equipment, rental loss during the period of repair or rebuild,
workmen's compensation insurance and fidelity bonds for employees employed to
perform services. Notwithstanding the foregoing, Landlord may, but shall not be
deemed required to, provide insurance as to any improvements installed by Tenant
or which are in addition to the standard improvements customarily furnished by
Landlord without regard to whether or not such are made a part of the Building.

         20.3. Landlord, as part of Operating Expenses, shall further carry
public and excess liability insurance with a single loss limit of not less than
Six Million Dollars ($6,000,000.00) per occurrence for death or bodily injury or
property damage with respect to the Project.

         20.4. Tenant assumes the risk of damage to any fixtures, goods,
inventory, merchandise, equipment, and leasehold improvements (other than Tenant
Improvements), and Landlord shall not be liable for injury to Tenant's business
or any loss of income therefrom relative to such damage as more particularly
heretofore set forth within this Lease, other than as a result of the willful
misconduct or gross negligence of Landlord or its agents, employees or
contractors. Tenant at Tenant's cost shall carry such insurance as Tenant
desires for Tenant's protection with respect to Tenant's personal property or
business interruption.

         20.5. Tenant at its own cost shall procure and continue in effect from
the Term Commencement Date or the date of occupancy, whichever first occurs, and
continuing throughout the Term (and occupancy by Tenant, if any, after
expiration or earlier termination of this Lease) comprehensive public and excess
liability insurance with limits of not less than



                                      -33-


<PAGE>   36
Six Million Dollars ($6,000,000.00) per occurrence for death or bodily injury or
property damage with respect to the Demised Premises or the Land.

         20.6. The aforesaid insurance required of Tenant shall name Landlord,
its officers, employees and agents, as an additional insured. Said insurance
shall be with companies having a rating of not less than policyholder rating of
A and financial category rating of at least Class XII in "Best's Insurance
Guide." No such policy shall be cancelable or subject to reduction of coverage
or other modification or cancellation except after thirty (30) days prior
written notice to Landlord from the insurer. All such policies shall be written
as primary policies, not contributing with and not in excess of the coverage
which Landlord may carry. Tenant's policy may be a "blanket policy" which
specifically provides that the amount of insurance shall not be prejudiced by
other losses covered by the policy. Tenant shall, at least twenty (20) days
prior to the expiration of such policies, furnish Landlord with renewals or
binders. Tenant agrees that if Tenant does not take out and maintain such
insurance, Landlord may (but shall not be required to) procure said insurance on
Tenant's behalf and require Tenant to pay for the additional cost of such
insurance as Additional Rent.

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

         20.8. Landlord and Tenant each hereby waive any and all rights of
recovery against the other or against the officers, directors, employees,
agents, and representatives of the other, on account of loss or damage
occasioned to such waiving party or its property or the property of others under
its control to the extent that such loss or damage is insured against under any
fire and extended coverage insurance policy which either may have in force at
the time of such loss or damage.

              20.8.1. Such waivers shall continue as long as their respective
insurers so permit.

              20.8.2. Any termination of such a waiver shall be by written
notice of circumstances as hereinafter set forth.

              20.8.3. Landlord and Tenant upon obtaining the policies of
insurance required or permitted under this Lease shall give notice to the
insurance carrier or carriers that the foregoing mutual waiver of subrogation is
contained in this Lease.



                                      -34-


<PAGE>   37
               20.8.4. If such policies shall not be obtainable with such waiver
or shall be so obtainable only at a premium over that chargeable without such
waiver, the party seeking such policy shall notify the other thereof, and the
latter shall have ten (10) days thereafter to either (i) procure such insurance
with companies reasonably satisfactory to the other party or (ii) agree to pay
such additional premium (in the Tenant's case, in the proportion which the area
of the Demised Premises bears to the insured area). If neither (i) nor (ii) are
done, this Section 20.8.4 shall have no effect during such time as such policies
shall not be obtainable or the party in whose favor a waiver of subrogation is
desired refuses to pay the additional premium. If such policies shall at any
time be unobtainable, but shall be subsequently obtainable, neither party shall
be subsequently liable for a failure to obtain such insurance until a reasonable
time after notification thereof by the other party.

               20.8.5. If the release of either Landlord or Tenant, as set forth
in this Article 20 shall contravene any law with respect to exculpatory
agreements, the liability of the party in question shall be deemed not released
but shall be secondary to the other's insurer.

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

         20.10. Tenant shall have the right to request that Landlord cause, and
Landlord shall use its reasonable efforts to cause, the insurance policy limits
to be raised, or additional coverages added, to the extent the same are
generally available from carriers complying with the requirements of this
Article 20, all at Tenant's sole cost and expense. Tenant agrees to execute any
such additional documentation reasonably required by Landlord or the insurance
carrier to reflect and confirm that Tenant shall be solely responsible for all
premiums and charges attributable to the increased insurance limit or additional
coverage requested by Tenant.

21.      Damage or Destruction

         21.1. Landlord shall promptly commence and proceed diligently with the
work of repair, reconstruction and restoration of the Building and this Lease
shall continue in full force and effect if there is partial destruction of the
Building (i) by fire or other perils covered by extended coverage insurance not
exceeding (x) twenty-five percent (25%) of the full insurable value thereof, or
(y) so long as at least five (5) years will remain in the Term (as may have been
extended pursuant to the terms of Section 39, provided that Tenant shall have
the right to exercise its Extension Right within 30 days of the occurrence of
such casualty) as of the date of completion of reconstruction, seventy-five
percent (75%) of the full insurable value thereof; (ii) the damage thereto is
such that the Building may be repaired, reconstructed, or restored within a
period of six (6) months from the date of the happening of such casualty; and
(iii) Landlord will receive insurance proceeds sufficient to cover the cost of
such repairs (except for any deductible amount provided by Landlord's policy,
which deductible amount if paid by



                                      -35-


<PAGE>   38
Landlord shall be an Operating Expense). Landlord shall use commercially
reasonable efforts to complete the restoration and repair of the Building within
six (6) months from the date of the happening of such casualty.

         21.2. Subject to the provisions of Section 21.7, in the event of any
damage to or destruction of the Building, other than as provided in Section
21.1, Landlord may elect to repair, reconstruct and restore the Building, in
which case this Lease shall continue in full force and effect. If Landlord
elects not to repair, then this Lease shall terminate as of the date of
destruction. If Landlord elects to repair, Landlord shall promptly commence such
repairs and shall diligently pursue such repairs to completion.

         21.3. Landlord shall give written notice to Tenant of its election not
to repair, reconstruct or restore the Building within sixty (60) days following
the date of damage or destruction.

         21.4. In the event of repair, reconstruction and restoration as herein
provided, the rental provided to be paid under this Lease shall be abated
proportionately based on the extent to which Tenant's use of the Demised
Premises is impaired during the period of such repair, reconstruction or
restoration, unless Landlord provides Tenant with other space during the period
of repair, which in Tenant's reasonable opinion is suitable for the temporary
conduct of Tenant's business.

         21.5. Notwithstanding anything to the contrary contained in this
Article, should Landlord be delayed or prevented from completing the repair or
restoration of the damage to the Demised Premises after the occurrence of such
damage or destruction by any Force-Majeure Delay, the time for Landlord to
commence or complete repairs shall be extended; provided, at the election of
either party exercisable by the delivery of written notice to the other party
not later than sixty (60) days after Landlord notifies Tenant of Landlord's
inability to complete the repairs by the end of the eight (8th) month following
such damage as a result of a Force-Majeure Delay, Landlord shall be relieved of
its obligation to make such repairs or restoration and Tenant shall be released
from its obligation under this Lease effective as of the date of the receipt of
such written notice.

         21.6. If Landlord is obligated to or elects to repair or restore as
herein provided, Landlord shall be obligated to make repairs or restoration only
of those portions of the Building and the Demised Premises which were originally
provided at Landlord's expense. The repair and restoration of items not provided
at Landlord's expense shall be the obligation of Tenant. In the event Tenant
elects to upgrade the Tenant Improvements, Landlord shall, upon the need for
replacement due to an insured loss, provide only the Tenant Improvements unless
Tenant shall elect to again upgrade and pay any additional cost of such
upgrades, except to such extent as insurance proceeds which, if received, the
excess proceeds are adequate to provide such upgrades, in addition to providing
for basic reconstruction and the Tenant Improvements.



                                      -36-


<PAGE>   39
         21.7. Notwithstanding anything to the contrary contained in this
Article, Landlord shall not have any obligation whatsoever to repair,
reconstruct or restore the Demised Premises (i) to the extent that insurance
proceeds are not available therefor, or (ii) when the damage resulting from any
casualty covered under this Article occurs during the last twenty-four (24)
months of the term of this Lease or any extension hereof and the cost to repair
such damage exceeds $250,000, unless with respect to this clause (ii) Tenant
shall, within thirty (30) days of the occurrence of such damage, exercise its
Extension Right pursuant to Article 39.

         21.8. Upon any termination of this Lease under any of the provisions of
this Article, the parties shall be released thereby without further obligation
to the other from the date Tenant surrenders possession of the Demised Premises
to the Landlord, except for items which have theretofore occurred.

22.      Eminent Domain

         22.1. In the event the whole of the Demised Premises or the Land, or
such part thereof as shall substantially interfere with the Tenant's use and
occupancy thereof, shall be taken for any public or quasi-public purpose by any
lawful power or authority by exercise of the right of appropriation,
condemnation or eminent domain, or sold to prevent such taking, Tenant or
Landlord may terminate this Lease effective as of the date possession is
required to be surrendered to said authority.

         22.2. [Intentionally omitted.]

         22.3. Tenant shall be entitled to any award which is specifically
awarded as compensation for the taking of Tenant's Property and for costs of
Tenant moving to a new location. To the extent not otherwise paid directly to
Tenant by the condemning authority, Tenant shall also be entitled to a pro rata
portion of any condemnation award paid to Landlord on account of Tenant
Improvements calculated based upon the ratio of the Tenant Improvements paid for
by Tenant in excess of the Tenant Improvement Allowance to the total cost of the
Tenant Improvements, up to a maximum of the unamortized amounts, if any, paid by
Tenant towards the Tenant Improvements. Except as before set forth, any award
for such taking shall belong to Landlord.

         22.4. If upon any taking of the nature described in this Article 22
this Lease continues in effect, the Landlord shall promptly proceed to restore
the Demised Premises, Building, and the Project to substantially their same
condition prior to such partial taking. To the extent such restoration is
feasible, as determined by Landlord in its sole discretion, the Rent shall be
abated proportionately based upon the extent to which Tenant's use of the
Demised Premises has decreased on the basis of the percentage of the rental
value of the Demised Premises after such taking and the rental value of the
Demised Premises prior to such taking.



                                      -37-


<PAGE>   40
23.      Defaults and Remedies

         23.1. The occurrence of any one or more of the following events shall
constitute a "Default" hereunder by Tenant:

               23.1.1. Tenant abandons or vacates the Demised Premises, provided
that, for so long as Tenant continues to perform all of its obligations under
this Lease, vacating the Demised Premises shall not be a Default hereunder;

               23.1.2. Tenant fails to make any payment of Rent, as and when due
and such failure continues for more than five (5) days following delivery of
written notice from Landlord (provided, however, that (i) no such notice shall
be required in the event that Landlord has given two (2) such notices to Tenant
within the preceding twelve (12) months, and (ii) such notice shall be in place
of, and not in addition to, any similar notice required under Maryland law);

               23.1.3. Tenant fails to observe or perform any obligation or
covenant contained herein (other than described in Section 23.1.1 and 23.1.2) to
be performed by Tenant, where such failure shall continue for a period of thirty
(30) days after written notice thereof from Landlord to Tenant; provided that if
the nature of Tenant's default is such that it reasonably requires more than
thirty (30) days to cure, then Tenant shall not be deemed to be in default if
Tenant shall commence such cure within said thirty (30) days and thereafter
diligently prosecute the same to completion;

               23.1.4. Tenant makes an assignment for the benefit of creditors;

               23.1.5. A receiver, trustee or custodian is appointed to, or
does, take title, possession or control of all, or substantially all, of
Tenant's assets;

               23.1.6. Tenant files a voluntary petition under the Bankruptcy
Code (or any similar law) or an order for relief is entered against Tenant
pursuant to a voluntary or involuntary proceeding commenced under any chapter of
the Bankruptcy Code;

               23.1.7. Any involuntary petition is filed against the Tenant
under any chapter of the Bankruptcy Code and is not dismissed within ninety (90)
days; or

               23.1.8. Tenant's interest in this Lease is attached, executed
upon, or otherwise judicially seized and such action is not released within
ninety (90) days of the action.

Notices given under this Section shall specify the alleged default and shall
demand that Tenant perform the provisions of this Lease or pay the Rent that is
in arrears, as the case may be, within the applicable period of time, or quit
the Demised Premises. No such notice shall be



                                      -38-


<PAGE>   41
deemed a forfeiture or a termination of this Lease unless Landlord elects
otherwise in such notice.

         23.2. Late payment by Tenant to Landlord of Rent and other sums due
will cause Landlord to incur costs not contemplated by this Lease, the exact
amount of which will be extremely difficult and impracticable to ascertain. Such
costs include, but are not limited to, late charges and processing and
accounting charges which may be imposed on Landlord by the terms of any mortgage
or trust deed covering the Demised Premises. Therefore, if any installment of
Rent due from Tenant is not received by Landlord within five (5) days after the
date such payment is due, Tenant shall pay to Landlord an additional sum of five
percent (5%) of the overdue Rent as a late charge. The parties agree that this
late charge represents a fair and reasonable estimate of the costs that Landlord
will incur by reason of late payment by Tenant. In addition to the late charge,
Rent not paid when due shall bear interest from the 5th day after date due until
paid at the lesser of (i) ten percent (10%) per annum or (ii) the maximum rate
permitted by law.

         23.3. No payment by Tenant or receipt by Landlord of a lesser amount
than the Rent payment herein stipulated shall be deemed to be other than on
account of the Rent, nor shall any endorsement or statement on any check or any
letter accompanying any check or payment as Rent be deemed an accord and
satisfaction, and Landlord may accept such check or payment without prejudice to
Landlord's right to recover the balance of such Rent or pursue any other remedy
provided. If at any time a dispute shall arise as to any amount or sum of money
to be paid by Tenant to Landlord, Tenant shall have the right to make payment
"under protest" and such payment shall not be regarded as a voluntary payment,
and Tenant's right to institute suit for recovery of the payment paid under
protest shall survive.

         23.4. If Tenant fails to pay any sum of money (other than Annual Base
Rent, Improvement Rent or Additional Rent) required to be paid by it hereunder,
or shall fail to perform any other act on its part to be performed hereunder,
Landlord may, without waiving or releasing Tenant from any obligations of
Tenant, but shall not be obligated to, make such payment or perform such act;
provided, that such failure by Tenant continues for ten (10) days after Landlord
delivers notice to Tenant demanding Tenant's performance or provided that such
failure by Tenant unreasonably interfered with the use of the Building by any
other tenant or with the efficient operation of the Building, or resulted or
could have resulted in a violation of law or the cancellation of an insurance
policy maintained by Landlord. All sums so paid or incurred by Landlord,
together with interest thereon, from the date such sums were paid or incurred,
at the annual rate equal to ten percent (10%) per annum or highest rate
permitted by law, whichever is less, shall be payable to Landlord on demand as
Additional Rent.

         23.5. In the event of a Default by Tenant, and at any time thereafter
while such Default is continuing, with or without notice or demand and without
limiting Landlord in the exercise of any right or remedy which Landlord may
have, Landlord shall be entitled to terminate Tenant's right to possession of
the Demised Premises by any lawful means, in which



                                      -39-


<PAGE>   42
case this Lease shall terminate and Tenant shall immediately surrender
possession of the Demised Premises to Landlord. In such event, Landlord shall
have the immediate right to re-enter and remove all Persons and property, and
such property may be removed and stored in a public warehouse or elsewhere at
the cost of, and for the account of Tenant, all without service of notice or
resort to legal process and without being deemed guilty of trespass, or becoming
liable for any loss or damage which may be occasioned thereby. In the event that
Landlord shall elect to so terminate this Lease, then Landlord shall be entitled
to recover from Tenant all actual damages incurred by Landlord by reason of
Tenant's default, including:

               23.5.1. The worth at the time of award of any unpaid Rent which
had been earned at the time of such termination; plus

               23.5.2. 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 that portion of such rental loss which Tenant proves could have
been reasonably avoided; plus

               23.5.3. 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 which Tenant proves could have been reasonably
avoided; plus

               23.5.4. Any other amount necessary to compensate Landlord for all
the actual damages proximately caused by Tenant's failure to perform its
obligation 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 restoring
the Demised Premises to the condition required under the terms of this Lease;
plus

               23.5.5. At the Landlord's election, such other amounts in
addition to or in lieu of the foregoing as may be permitted from time to time by
applicable law other than special or speculative damages.

As used in Sections 23.5.1 and 23.5.2 above, "worth at the time of award" shall
be computed by allowing interest at the rate specified in Section 23.2. As used
in Section 23.5.3 above, the "worth at the time of the award" shall be computed
by taking the present value of such amount, by using the discount rate of the
Federal Reserve Bank of San Francisco at the time of the award plus six (6)
percentage points.

         23.6. If Landlord does not elect to terminate this Lease as provided in
this Section, then Landlord may, from time to time, recover all Rent as it
becomes due under this Lease. At any time thereafter, Landlord may elect to
terminate this Lease and to recover damage to which Landlord is entitled.

         23.7. In the event Landlord elects to terminate this Lease and relet
the Demised Premises, it may execute any new lease in its own name. Tenant
hereunder shall have no right



                                      -40-


<PAGE>   43
or authority whatsoever to collect any Rent from such tenant. The proceeds of
any such reletting shall be applied as follows:

               First, to the payment of any indebtedness other than Rent due
hereunder from Tenant to Landlord, including, but not limited to, storage
charges or brokerage commissions owing from Tenant to Landlord as the result of
such reletting;

               Second, to the payment of the costs and expenses of reletting the
Demised Premises, including alterations and repairs which Landlord deems
reasonably necessary and advisable and reasonable attorneys' fees, charges and
disbursements incurred by Landlord in connection with the retaking of the
Demised Premises and such reletting;

               Third, to the payment of Rent and other charges due and unpaid
hereunder; and

               Fourth, to the payment of future Rent and other damages payable
by Tenant under this Lease.

         23.8. All rights, options, and remedies of Landlord contained in this
Lease shall be construed and held to be nonexclusive and cumulative. Landlord
shall have the right to pursue any one or all of such rights, options and
remedies or any other remedy or relief which may be provided by law, whether or
not stated in this Lease. No waiver of any default of Tenant hereunder shall be
implied from any acceptance by Landlord of any Rent or other payments due
hereunder or any omission by Landlord to take any action on account of such
default if such default persists or is repeated, and no express waiver shall
affect defaults other than as specified in said waiver.

         23.9. All rights, options and remedies of Tenant contained in this
Lease shall be construed and held to be nonexclusive and cumulative. Tenant
shall have the right to pursue any one or all of such rights, options and
remedies or any other remedy or relief which may be provided by law, whether or
not stated in this Lease. No waiver of any default of Landlord hereunder shall
be implied from any omission by Tenant to take any action on account of such
default if such default persists or is repeated, and no express waiver of any
default of Landlord hereunder shall affect defaults other than as specified in
said waiver.

         23.10. Termination of this Lease or Tenant's right to possession by
Landlord shall not relieve Tenant from any liability to Landlord which has
theretofore accrued or shall arise based upon events which occurred prior to the
last to occur of (i) the date of Lease termination or (ii) the date possession
of Demised Premises is surrendered. Termination of this Lease or by Tenant as
specifically permitted herein shall not relieve Landlord from any liability to
Tenant which has theretofore accrued or shall arise based upon events which
occurred prior to the last to occur of (i) the date of Lease termination or (ii)
the date possession of Demised Premises is surrendered.



                                      -41-


<PAGE>   44
         23.11. Landlord shall not be in default unless Landlord fails to
perform obligations required of Landlord within a reasonable time, but in no
event shall such failure to continue be for more than thirty (30) days after
written notice by Tenant specifying wherein Landlord has failed to perform such
obligation; provided, however, that if the nature of Landlord's obligation is
such that more than thirty (30) days are required for performance, then Landlord
shall not be in default if Landlord commences performance within such thirty
(30) day period and thereafter diligently prosecutes the same to completion.

         23.12. In the event of any default on the part of Landlord, Tenant will
give notice by registered or certified mail to any beneficiary of a deed of
trust or mortgagee of a mortgage covering the Demised Premises and to any
landlord of any lease of any building in which the Demised Premises are located
whose address shall have been furnished, provided that Landlord shall have
furnished to Tenant in writing the names and addresses of all such Persons who
are to receive such notices. Any such beneficiary, mortgagee or landlord shall
have thirty (30) days from receipt of such notice from Tenant to cure the
default if the default can be fully cured by the payment of a specific and
liquidated amount of money. Any such beneficiary, mortgagee or landlord shall
have ninety (90) days from receipt of such notice from Tenant to cure the
default if the default cannot be fully cured by the payment of a specific and
liquidated amount of money and possession is not reasonably required to cure the
default. In the event possession is reasonably required to cure the default and
unless Tenant shall provided all access necessary to affect a cure, any such
beneficiary, mortgagee or landlord shall promptly commence taking steps to
obtain possession of the Premises by foreclosure or the judicial appointment of
a receiver after receipt of Tenant's written notice of the default, and shall
thereafter diligently continue to attempt to cure the default within the minimum
period of time reasonably required under the circumstances to achieve a cure.

24.      Assignment or Subletting

         24.1. Except as hereinafter provided, Tenant shall not, either
voluntarily or by operation of law, directly or indirectly, sell, hypothecate,
assign, pledge, encumber or otherwise transfer this Lease, or sublet the Demised
Premises or any part thereof, or permit or suffer the Demised Premises or any
part thereof to be used or occupied as work space, storage space, mailing
privileges, concession or otherwise by anyone other than Tenant or Tenant's
employees, without the prior written consent of Landlord in each instance, which
consent shall not be unreasonably withheld.

         24.2. If Tenant is a corporation, the shares of which are not actively
traded upon a stock exchange or in the over-the-counter market, a transfer or
series of transfers whereby twenty-five percent (25%) or more of the issued and
outstanding shares of such corporation are, or the voting control is,
transferred (but excepting transfers upon deaths of individual shareholders)
from a Person or Persons or entity or entities which were owners thereof at time
of execution of this Lease to Persons or entities who were not owners of shares
of the



                                      -42-


<PAGE>   45
corporation at time of execution of this Lease shall be deemed an assignment of
this Lease requiring the consent of Landlord as provided in Section 24.1 above.

         24.3. If Tenant desires to assign this Lease to any entity into which
Tenant is merged, with which Tenant is consolidated, or which acquires all or
substantially all of the assets of Tenant, provided that the assignee first
executes, acknowledges, and delivers to Landlord an agreement whereby the
assignee agrees to be bound by all of the covenants and agreements in this Lease
and that the assignee shall have a net worth (determined in accordance with
generally accepted accounting principles consistently applied) immediately after
such assignment which is at least equal to the net worth (as so determined) of
Tenant immediately prior to the assignment (or as of the date hereof, if
greater), then Landlord, upon receipt of proof of foregoing, shall consent to
such assignment.

         24.4. In the event Tenant desires to assign, sublease, hypothecate or
otherwise transfer this Lease or sublet the Demised Premises, then at least
forty-five (45) days, but not more than ninety (90) days, prior to the
Assignment Date, Tenant shall give Landlord the Assignment Notice. Tenant shall
also tender to Landlord reasonable attorneys fees and other costs or overhead
expenses incurred by Landlord in reviewing Tenants request for such assignment.
In addition to the Assignment Notice, Tenant shall promptly provide Landlord
with such other information as Landlord may reasonably require in connection
with any proposed assignment or subletting (including, without limitation, an
assignment pursuant to Section 24.3).

         24.5. With respect to proposed assignments or sublettings where
Landlord's consent is required, Landlord in making its determination as to
whether such consent should be given to a proposed assignment or sublease, may
give consideration to the financial strength of such successor (notwithstanding
the assignor remaining liable for Tenant's performance), any change in use which
such successor proposes to make in use of Demised Premises and desire of
Landlord to exercise rights under Section 24.10 to obtain cancellation of this
Lease. In no event shall Landlord be deemed to be unreasonable for declining to
consent to transfer to a successor of poor reputation, lacking financial
qualifications, or seeking change in use.



                                      -43-


<PAGE>   46
         24.6. As conditions precedent to Landlord considering a request by
Tenant to Tenant's transfer of rights or sharing of the Demised Premises with
respect to proposed assignments or sublettings where Landlord's consent is
required, Landlord may require any or all of the following:

               24.6.1. Tenant shall remain fully liable under this Lease during
the unexpired Term;

               24.6.2. Tenant shall provide Landlord with evidence reasonably
satisfactory to Landlord that the value of Landlord's interest under this Lease
will not thereby be diminished or reduced. Such evidence shall include, but need
not be limited to, evidence respecting the relevant business experience and
financial responsibility and status of the third party concerned;

               24.6.3. Tenant shall reimburse Landlord for Landlord's actual
costs and expenses, including, without limitation, reasonable attorneys' fees,
charges and disbursements incurred in connection with the review, processing and
documentation of such request;

               24.6.4. If Tenant's transfer of rights or sharing of the Demised
Premises provides for the receipt by, on behalf or on account of Tenant of any
consideration of any kind whatsoever (including, but not by way of limitation, a
premium rental for a sublease or lump sum payment for an assignment) in excess
of the rental and other charges due Landlord under this Lease, Tenant shall pay
all of said excess to Landlord. If said consideration consists of cash paid to
Tenant, said payment to Landlord shall be made upon receipt by Tenant of said
cash payment;

               24.6.5. Written agreement from any third party concerned that in
the event Landlord gives such third party notice that Tenant is in default under
this Lease, such third party shall thereafter make all payments otherwise due
Tenant directly to Landlord, which payments will be received by Landlord without
any liability on Landlord except to credit such payment against those due under
the Lease, and any such third party shall agree to attorn to Landlord or its
successors and assigns should this Lease be terminated for any reason; provided,
however that in no event shall Landlord or its successors or assigns be
obligated to accept such attornment;

               24.6.6. Any such transfer and consent shall be effected on forms
reasonably approved by Landlord as to form and substance;

               24.6.7. Tenant shall not then be in default hereunder in any
respect;

               24.6.8. Such third party's proposed use of the Demised Premises
shall be the same as Tenant's permitted use;



                                      -44-


<PAGE>   47
               24.6.9. Landlord shall not be bound by any provision of any
agreement pertaining to Tenant's transfer of rights or sharing of the Demised
Premises unless Landlord becomes a party to such agreement;

               24.6.10. Any agreement pertaining to Tenant's transfer of this
Lease or subletting of all or any portion of the Demised Premises shall be in a
form acceptable to Landlord in Landlord's reasonable discretion and any such
agreement shall not be modified or amended without Landlord's prior written
consent, which may be withheld in Landlord's reasonable discretion. Tenant
acknowledges and agrees that Landlord shall be acting reasonably in the event
Landlord withholds its consent to any such agreement if, in the opinion of
Landlord's counsel, the agreement or any portion thereof would be likely to
result in Landlord losing its status as a real estate investment trust, as
defined in Section 856 of the Internal Revenue Code (as amended).

               24.6.11. Tenant shall deliver to Landlord one executed copy of
any and all written instruments evidencing Tenant's transfer of rights or
sharing of the Demised Premises; and

               24.6.12. A list of Hazardous Materials certified by the proposed
sublessee to be true and correct, which the proposed sublessee intends to use or
store in the Demised Premises. Additionally, Tenant shall deliver to Landlord,
on or before the date any proposed sublessee takes occupancy of the Demised
Premises, all of the items relating to Hazardous Materials of such proposed
sublessee as described in Article 38 below.

         24.7. Any sale, assignment, hypothecation or transfer of this Lease or
subletting of the Demised Premises that is not in compliance with the provisions
of this Article 24 shall be void and shall, at the option of Landlord, terminate
this Lease.

         24.8. The consent by Landlord to an assignment or subletting shall not
relieve Tenant or any assignees of this Lease or sublessee of the Demised
Premises from obtaining the consent of Landlord to any further assignment or
subletting nor shall it release Tenant or any assignee or sublessee of Tenant
from full and primary liability under the Lease.

         24.9. Notwithstanding any subletting or assignment, Tenant shall remain
fully and primarily liable for the payment of all Rent and other sums due, or to
become due hereunder, and for the full performance of all other terms,
conditions, and covenants to be kept and performed by Tenant. The acceptance of
Rent or any other sum due hereunder, or the acceptance of performance of any
other term, covenant, or condition thereof, from any other Person or entity
shall not be deemed to be a waiver of any of the provisions of this Lease or a
consent to any subletting, assignment or other transfer of the Demised Premises.



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<PAGE>   48
         24.10. If Tenant delivers to Landlord an Assignment Notice indicating a
desire to transfer this Lease to a transferee other than as provided within
Section 24.3 or to a transferee with respect to which Landlord reasonably
withholds its consent, then Landlord shall have the option, exercisable by
giving notice to Tenant at any time within ten (10) days after Landlord's
receipt of the Assignment Notice, to terminate this Lease as of the date
specified in the Assignment Notice as the Assignment Date. If Landlord exercises
such option, then Tenant shall have the right to withdraw such Assignment Notice
by delivery to Landlord written notice of such election within five (5) days
after Landlord's delivery of notice electing to exercise such option to
terminate. In the event Tenant withdraws the Assignment Notice as hereinabove
provided, this Lease shall continue in full force and effect as if such
Assignment Notice as hereinabove provided, this Lease, and the term and estate
herein granted, shall terminate as of the Assignment Date. No failure of
Landlord to exercise any such option to terminate this Lease shall be deemed to
be Landlord's consent to the proposed Assignment, Sublease or other Transfer.

         24.11. If Tenant shall sublet the Demised Premises or any part, Tenant
hereby immediately and irrevocably assigns to Landlord, as security for Tenant's
obligations under this Lease, all rent from any subletting of all or a part of
the Demised Premises and Landlord as assignee and as attorney-in-fact for
Tenant, or a receiver for Tenant appointed on Landlord's application, may
collect such rent and apply it toward Tenant's obligations under this Lease;
except that, until the occurrence of an act of Default by Tenant, Tenant shall
have the right to collect such rent.

25.      Attorneys' Fees

         25.1. Landlord and Tenant shall each be responsible for all of their
respective legal and related costs associated with this Lease and related
transaction; provided, however, that Tenant shall not be responsible for
Landlord's legal costs with respect to site acquisition, site improvements,
public approval, and lease and drafting negotiations associated with this Lease
and related transaction.

         25.2. If either party commences an action against the other party
arising out of or in connection with this Lease, the prevailing party shall be
entitled to have and recover from the non-prevailing party reasonable attorneys'
fees, charges and disbursements and costs of suit.

26.      Bankruptcy

         26.1. In the event a debtor, trustee, or debtor in possession under the
Bankruptcy Code, or other Person with similar rights, duties and powers under
any other law, proposes to cure any default under this Lease or to assume or
assign this Lease, and is obliged to provide adequate assurance to Landlord that
(i) a default will be cured, (ii) Landlord will be compensated for its damages
arising from any breach of this Lease, or (iii) future performance



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<PAGE>   49
under this Lease will occur, then adequate assurance shall include any or all of
the following, as designated by Landlord:

               26.1.1. Those acts specified in the Bankruptcy Code or other law
as included within the meaning of adequate assurance, even if this Lease does
not concern a shopping center or other facility described in such laws;

               26.1.2. A prompt cash payment to compensate Landlord for any
monetary defaults or actual damages arising directly from a breach of this
Lease;

               26.1.3. A cash deposit in an amount at least equal to the
Security Deposit as referenced in 2.1.9 originally required at time of execution
of this Lease.

               26.1.4. The assumption or assignment of all of Tenant's interest
and obligations under this Lease.

27.      Estoppel Certificate

         Each of Tenant and Landlord shall, within ten (10) days of written
notice from the other party hereto, execute, acknowledge and deliver a statement
in writing substantially in the form attached to this Lease as Exhibit "H" with
the blanks filled in with respect to any estoppel to be executed by Tenant, and
on any other form reasonably requested by a proposed lender, purchaser,
assignee, subtenant or transferee of Landlord or Tenant, (i) certifying that
this Lease is unmodified and in full force and effect (or, if modified, stating
the nature of such modification and certifying that this Lease as so modified is
in full force and effect) and the dates to which the rental and other charges
are paid in advanced, if any, (ii) acknowledging that there are not, to such
party's knowledge, any uncured defaults on the part of the other party
hereunder, or specifying such defaults if any are claimed and (iii) setting
forth such further information with respect to this Lease or the Demised
Premises or the Project as may be reasonably requested thereon. Any such
statement may be relied upon by any prospective assignee, subtenant, transferee,
purchaser or encumbrancer of all or any portion of the Lease or the real
property of which the Demised Premises are a part. Failure to deliver such
statement within such time shall, at the option of the requesting party,
constitute a default under this Lease, and, in any event, shall be conclusive
upon the non-requesting party that the Lease is in full force and effect and
without modification except as may be represented by the requesting party in any
certificate prepared and delivered for execution.

28.      Joint and Several Obligations

         28.1. If more than one Person or entity executes this Lease as Tenant,



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<PAGE>   50
               28.1.1. Each of them is jointly and severally liable for the
keeping, observing and performing of all of the terms, covenants, conditions,
provisions and agreements of this Lease to be kept, observed and performed by
Tenant, and

               28.1.2. The term "Tenant" as used in this Lease shall mean and
include each of them jointly and severally. The act of, notice from, notice to,
refund to, or the signature of, any one or more of them, with respect to the
tenancy of this Lease, including, but not limited to, any renewal, extension,
expiration, termination or modification of this Lease, shall be binding upon
each and all of the Persons executing this Lease as Tenant with the same force
and effect as if each and all of them had so acted, so given or received such
notice or refund or so signed.

29.      Definition of Landlord; Limitation of Landlord's Liability

         29.1. The term "Landlord" as used in this Lease, so far as covenants or
obligations on the part of Landlord are concerned, shall be limited to mean and
include only Landlord or the successor-in-interest of Landlord under this Lease
at the time in question. In the event of any transfer, assignment or the
conveyance of Landlord's title or leasehold, the Landlord herein named (and in
case of any subsequent transfers or conveyances, the then grantor) shall be
automatically freed and relieved from and after the date of such transfer,
assignment or conveyance, of all liability for the performance of any covenants
or obligations contained in this Lease thereafter to be performed by Landlord
and, without further agreement, the transferee of such title or leasehold shall
be deemed to have assumed and agreed to observe and perform any and all
obligations of Landlord hereunder, during its ownership or ground lease of the
Demised Premises. Landlord may transfer its interest in the Demised Premises or
this Lease without the consent of Tenant and such transfer or subsequent
transfer shall not be deemed a violation on the part of Landlord or the then
grantor of any of the terms or conditions of this Lease. Landlord shall promptly
notify Tenant in writing of any transfer of any portion of Landlord's interest
under this Lease. No transfer by Landlord of its interest in the Demised
Premises or this Lease shall be deemed to release Landlord from any obligations
to Tenant arising prior to such transfer.

         29.2. If Landlord is in default of this Lease, and as a consequence,
Tenant recovers a money judgment against Landlord, the judgment shall be
satisfied only out of the proceeds of sale received on execution of the judgment
and levy against the right, title and interest of Landlord in the Building or
Land, and out of rent or other income from such real property receivable by
Landlord or out of the consideration received by Landlord from the sale,
financing, refinancing, or other disposition of all or any part of Landlord's
right, title, and interest in the Building or Land.

         29.3. Except as provided in Section 29.2, Landlord shall not be
personally liable for any deficiency. If Landlord is a partnership or joint
venture, the partners of such partnership shall not be personally liable and no
partner of Landlord shall be sued or named as a party in



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<PAGE>   51
any suit or action or service of process be made against any partner of Landlord
except as may be necessary to secure jurisdiction of the partnership or joint
venture. If Landlord is a corporation, the shareholders, directors, officers,
employees, and/or agents of such corporation shall not be personally liable and
no shareholder, director, officer, employee or agent of Landlord shall be sued
or named as a party in any suit or action or service of process made against any
shareholder, director, officer, employee or agent of Landlord. If Landlord is a
limited liability company, the members of such limited liability company shall
not be personally liable and no member of Landlord shall be sued or named as a
party in any suit or action or service of process be made against any member of
Landlord except as may be necessary to secure jurisdiction over Landlord. No
partner, member, shareholder, director, employee, or agent of Landlord shall be
required to answer or otherwise plead to any service of process and no judgment
will be taken or writ of execution levied against any partner, shareholder,
director, employee or agent of Landlord.

         29.4. Each of the covenants and agreements of this Article 29 shall be
applicable to any covenant or agreement either expressly contained in this Lease
or imposed by statute or by common law and shall survive the termination of this
Lease.

30.      Project Control by Landlord

         30.1. Subject to Section 40.2, Landlord reserves full control over the
Building and the Project to the extent not inconsistent with Tenant's rights
under this Lease or enjoyment of the Demised Premises. This reservation includes
but is not limited to the right of Landlord to expand the Project, to subdivide
the Project, to convert the Building and or other buildings within the Project
to condominium units, to grant easements and licenses to others, and to maintain
or establish ownership of the Building separate from fee title to land on which
the Building is located.

         30.2. Tenant shall, should Landlord so request, promptly join with
Landlord in execution of such documents as may be reasonably appropriate to
assist Landlord to implement any such action provided Tenant need not execute
any document which is of nature wherein liability is created in Tenant or if by
reason of the terms of such document, Tenant will be deprived of the quiet
enjoyment and use of the Demised Premises as granted by this Lease or Tenant's
rights hereunder will be impaired.

         30.3. Subject to Section 40.2, Landlord may, at any and all reasonable
times during non-business hours or during business hours, and upon reasonable
advance notice (provided that no time restrictions shall apply or advance notice
need be given if an emergency necessitates an immediate entry), enter the
Demised Premises to (a) inspect the same and to determine whether Tenant is in
compliance with its obligations hereunder, (b) supply any service Landlord is
required to provide hereunder, (c) show the Demised Premises to prospective
lenders, insurers, investors, purchasers or, during the last two (2) years of
the Term, tenants, (d) post notices of nonresponsibility, (e) access the
telephone equipment,



                                      -49-


<PAGE>   52
electrical substations and fire risers, and (f) alter, improve or repair any
portion of the Building other than the Demised Premises, but for which access to
the Demised Premises is necessary. In connection with any such alteration,
improvement or repair, Landlord may erect in the Demised Premises or elsewhere
in the Building or the Project scaffolding and other structures reasonably
required for the work to be performed. In no event shall Tenant's Rent abate as
a result of any such entry or work; provided, however, that all such work shall
be done in such a manner as to cause as little interference to Tenant as
reasonably possible. Landlord shall at all times retain a key with which to
unlock all of the doors in the Demised Premises subject to Tenant's rights to
establish "secure" areas pursuant to Section 10.8. If an emergency necessitates
immediate access to the Demised Premises, Landlord may use whatever force is
necessary to enter the Demised Premises and any such entry to the Demised
Premises shall not constitute a forcible or unlawful entry to the Demised
Premises, a detainer of the Demised Premises, or an eviction of Tenant from the
Demised Premises, or any portion thereof.

         30.4. Landlord further reserves the right to combine the Project with
any other project in the area of the Project and owned by Landlord or its
affiliates. In the event Landlord elects to combine the Project, (i) the
definition of Project as used herein, shall be deemed to include all of land on
which the other project(s) is located, all of the buildings located thereon and
all landscaping, parking facilities and other improvements and appurtenances
related thereto, including, without limitation, driveways, sidewalks, parking
areas, and landscaped areas, and (ii) the definitions of Rentable Area of the
Project, Tenant's Pro Rata Share of Project, and Project Common Areas shall be
revised to reflect the inclusion of such other project(s); provided, however,
that there shall be no net increase in Tenant's Pro Rata Share of Project
Operating Expenses resulting solely as a result of the combination of the
Project with any other project.

31.      Quiet Enjoyment

         So long as Tenant is not in Default, Landlord covenants that Landlord
or anyone acting through or under Landlord will not disturb Tenant's occupancy
of the Demised Premises except as permitted by the provisions of this Lease, and
Tenant shall have the benefit of quiet enjoyment of the Demised Premises.

32.      Quitclaim Deed

         Tenant shall execute and deliver to Landlord on the expiration or
termination of this Lease, immediately on Landlord's request, in recordable
form, a quitclaim deed to the Demised Premises or such other documentation
reasonably requested by Landlord evidencing termination of this Lease.
Concurrently with the delivery to Landlord of such executed quitclaim deed,
Landlord shall deliver to Tenant written confirmation of the termination of this
Lease.



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<PAGE>   53
33.      Rules and Regulations

         Tenant shall faithfully observe and comply with the Rules and
Regulations and all reasonable and nondiscriminatory modifications thereof and
additions thereto from time to time put into effect by Landlord. Landlord agrees
to enforce the Rules and Regulations in a nondiscriminatory manner against all
the tenants of the Project. Landlord shall not be responsible to Tenant for the
violation or non-performance by any other tenant or any agent, employee or
invitee thereof of any of said Rules and Regulations.

34.      Subordination and Attornment

         34.1. This Lease shall be subject and subordinate to the lien of any
mortgage, deed of trust, or lease in which Landlord is tenant now or hereafter
in force against the Project and the Building and to all advances made or
hereafter to be made upon the security thereof without the necessity of the
execution and delivery of any further instruments on the part of Tenant to
effectuate such subordination provided that Tenant receives a non-disturbance
agreement from any such mortgagee, beneficiary or landlord in substantially the
same form as Exhibit "J" attached hereto (the "Nondisturbance Agreement").

         34.2. Provided that Tenant receives the Nondisturbance Agreement,
Tenant shall execute and deliver upon demand such further instrument or
instruments evidencing such subordination of this Lease to the lien of any such
mortgage or mortgages or deeds of trust or lease in which Landlord is tenant as
may be required by Landlord. However, if any such mortgagee, beneficiary or
Landlord under lease wherein Landlord is tenant so elects, this Lease shall be
deemed prior in lien to any such lease, mortgage, or deed of trust upon or
including the Demised Premises regardless of date and Tenant will execute a
statement in writing to such effect at Landlord's request. If Tenant fails to
execute any document required from Tenant under this Section within ten (10)
days after written request therefor, Tenant hereby constitutes and appoints
Landlord or its special attorney-in-fact to execute and deliver any such
document or documents in the name of Tenant. Such power is coupled with an
interest and is irrevocable.

         34.3. Provided that Tenant receives the Nondisturbance Agreement, in
the event any proceedings are brought for foreclosure, or in the event of the
exercise of the power of sale under any mortgage or deed of trust made by the
Landlord covering the Demised Premises, the Tenant shall at the election of the
purchaser at such foreclosure or sale attorn to the purchaser upon any such
foreclosure or sale and recognize such purchaser as the Landlord under this
Lease so long as such purchaser recognizes Tenant as tenant under this Lease and
such purchaser agrees to perform all of Landlord's duties and obligations
hereunder arising from and after the date of such foreclosure or sale.



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<PAGE>   54
35.      Surrender

         35.1. No surrender of possession of any part of the Demised Premises
shall release Tenant from any of its obligations hereunder unless accepted by
Landlord.

         35.2. The voluntary or other surrender of this Lease by Tenant shall
not work a merger, unless Landlord consents and shall, at the option of
Landlord, operate as an assignment to it of any or all subleases or
subtenancies.

         35.3. The voluntary or other surrender of any ground or underlying
lease that now exists or may hereafter be executed affecting the Building or
Project, or a mutual cancellation, thereof, or of Landlord's interest therein,
shall not work a merger and shall, at the option of the successor of Landlord's
interest in the Building or Project, operate as an assignment of this Lease.

         35.4. Upon the expiration or earlier termination of this Lease, Tenant
shall surrender the Demised Premises to Landlord broom clean and free of debris
and with all licenses, permits and similar items which restrict or affect the
use of the Demised Premises released and fully terminated and, subject to
Article 16, with all of Tenant's Personal Property and effects removed
therefrom; with all alterations, improvements and fixtures required by Landlord
to be removed from the Demised Premises actually removed and all damage as a
result of or caused by such removal repaired.

36.      Waiver and Modification

         No provision of this Lease may be modified, amended or added to except
by an agreement in writing. The waiver by Landlord or Tenant of any breach of
any term, covenant or condition herein contained shall not be deemed to be a
waiver of any subsequent breach of the same or any other term, covenant or
condition herein contained.

37.      Waiver of Jury Trial and Counterclaims

         THE PARTIES HERETO SHALL AND THEY HEREBY DO WAIVE TRIAL BY JURY IN ANY
ACTION, PROCEEDING OR COUNTERCLAIM BROUGHT BY EITHER OF THE PARTIES HERETO
AGAINST THE OTHER ON ANY MATTERS WHATSOEVER ARISING OUT OF OR IN ANY WAY
CONNECTED WITH THIS LEASE, THE RELATIONSHIP OF LANDLORD AND TENANT, TENANT'S USE
OR OCCUPANCY OF THE DEMISED PREMISES, AND OR ANY CLAIM OF INJURY OR DAMAGE.



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<PAGE>   55
38.      Hazardous Materials

         38.1. Prohibition/Compliance. Tenant shall not cause or permit any
Hazardous Material (as hereinafter defined) to be brought upon, kept or used in
or about the Demised Premises, the Building or the Project in violation of
applicable law by Tenant, its agents, employees, contractors or invitees. If
Tenant breaches the obligation stated in the preceding sentence, or if the
presence of Hazardous Materials results in contamination of the Demised
Premises, the Building, the Project or any adjacent property, or if
contamination of the Demised Premises, the Building, the Project or any adjacent
property by Hazardous Material otherwise occurs during the term of this Lease or
any extension or renewal hereof or holding over hereunder which is caused by any
act or omission of Tenant or its agents, employees or contractors, then Tenant
shall indemnify, defend and hold Landlord, its officers, directors, employees,
agents and contractors harmless from any and all claims, judgments, damages
(other than special or speculative damages), penalties, fines, costs,
liabilities, or losses (including, without limitation, diminution in value of
the Demised Premises, the Building or any portion of the Project, damages for
the loss or restriction on use of rentable or usable space or of any amenity of
the Demised Premises, the Building or the Project, damages arising from any
adverse impact on marketing of space in the Demised Premises, the Building or
the Project, and sums paid in settlement of claims, reasonable attorneys' fees,
reasonable consultant fees and expert fees) which arise during or after the
Lease term as a result of such contamination. This indemnification of Landlord
by Tenant includes, without limitation, costs incurred in connection with any
investigation of site conditions or any cleanup, remedial, removal, or
restoration work required by any federal, state or local governmental agency or
political subdivision because of Hazardous Material present in the air, soil or
ground water above on or under the Demised Premises which is caused by any act
or omission of Tenant or its agents, employees or contractors. Without limiting
the foregoing, if the presence of any Hazardous Material on the Demised
Premises, the Building, the Project or any adjacent property, caused or
permitted by Tenant results in any contamination of the Demised Premises, the
Building, the Project or any adjacent property, Tenant shall promptly take all
actions at its sole expense as are necessary to return the Demised Premises, the
Building, the Project or any adjacent property to the condition existing prior
to the time of such contamination, provided that Landlord's approval of such
action shall first be obtained, which approval shall not unreasonably be
withheld, delayed or conditioned so long as such actions would not potentially
have any material adverse long-term or short-term effect on the Demised
Premises, the Building or the Project. Landlord shall not cause or permit any
Hazardous Material (as hereinafter defined) to be brought upon, kept or used in
or about the Demised Premises, the Building, the Land or the Project in
violation of applicable law. Landlord agrees to remove or relocate, as and to
the extent required by the Maryland Department of the Environment, at Landlord's
expense prior to the Term Commencement Date, all existing ground water
monitoring wells located at the Project. Landlord shall, prior to acquisition of
the Project, apply to the Environmental Protection Agency to have the Project
removed from the RCRA generator data base, and shall thereafter diligently
prosecute such application to completion.



                                      -53-


<PAGE>   56
         38.2. Business. Landlord acknowledges that it is not the intent of this
Article 38 to prohibit Tenant from operating its business as described in
Section 2.1.10. Tenant may operate its business according to the custom of the
industry so long as the use or presence of Hazardous Material is in compliance
with all applicable governmental requirements.

               38.2.1. As a material inducement to Landlord to allow Tenant to
use Hazardous Material in connection with its business, Tenant agrees to deliver
to Landlord prior to the Term Commencement Date the Hazardous Material List
which shall then be attached as Exhibit "K".

               38.2.2. As a material inducement to Landlord to allow Tenant to
use Hazardous Material in connection with its business, Tenant agrees to deliver
to Landlord true and correct copies of the following documents (the "Documents")
relating to the handling, storage, disposal and emission of Hazardous Material
prior to the Term Commencement Date, or if unavailable at that time, concurrent
with the receipt from or submission to a governmental agency: permits;
approvals; material reports and correspondence; written storage and management
plans, notice of violations of any laws; plans relating to the installation of
any storage tanks to be installed in or under the Building or the Project
(provided, said installation of tanks shall only be permitted after Landlord has
given Tenant its written consent to do so, which consent may be withheld in
Landlord's sole and absolute discretion); and all closure plans or any other
documents required by any and all federal, state and local governmental agencies
and authorities for any storage tanks installed in, on or under the Building or
the Project for the closure of any such tanks. Tenant is not required, however,
to provide Landlord with any portion(s) of the Documents containing information
of a proprietary nature which, in and of themselves, do not contain a reference
to any Hazardous Material or hazardous activities. Landlord shall not disclose
the Documents to any third- parties other than Landlord's agents, employees,
contractors, consultants, attorneys, lenders (if any), insurers, investment
bankers, investors, or to such parties as required by law, provided that
Landlord shall inform all Persons receiving such information from Landlord of
the confidentiality requirement and in the event that Tenant so requests,
Landlord shall obtain their undertaking as to confidentiality in a form
reasonably acceptable to Tenant prior to disclosing the same. Notwithstanding
anything to the contrary set forth in this Section 38.2.2, Tenant is not
required to provide Landlord with information which could be detrimental to
Tenant's business should such information become possessed by Tenant's
competitors or by other third parties (but only to the extent such information
is not otherwise required by applicable law to be disclosed by Tenant with
respect to such third parties).

               38.2.3. Tenant shall deliver to Landlord an updated Hazardous
Material List at least once a year and shall also deliver an updated list before
any new Hazardous Material is brought onto the Demised Premises.



                                      -54-


<PAGE>   57
               38.2.4. Neither Landlord nor Tenant shall install any underground
storage tanks on the Land without the prior written consent of the other party
hereto, which consent may be withheld in such party's sole and absolute
discretion.

         38.3. [Intentionally omitted.]

         38.4. Testing. At any time, and from time to time, prior to the
expiration or earlier termination of the Term, Landlord shall have the right to
conduct appropriate tests of the Demised Premises, Building and Project to
demonstrate that contamination has occurred as a result of Tenant's use of the
Demised Premises. Tenant shall be solely responsible for and shall defend,
indemnify and hold the Landlord, its agents and contractors harmless from and
against any and all claims, costs and liabilities including actual attorneys'
fees, charges and disbursements, arising out of or in connection with any
removal, clean up, restoration and materials required hereunder to return the
Demised Premises and any other property of whatever nature to their condition
existing prior to the time of any such contamination to the extent caused by
Tenant or its agents, employees or contractors. Tenant shall pay for the cost of
the tests of the Demised Premises.

         38.5. Underground Tanks. If underground or other storage tanks storing
Hazardous Materials are located on the Demised Premises or are hereafter placed
on the Demised Premises by at the request of or for the benefit of Tenant,
Tenant shall monitor the storage tanks, maintain appropriate records, implement
reporting procedures, properly close any underground storage tanks, and take or
cause to be taken all other steps necessary or required under all applicable
local, state and federal laws and regulations, as they now exist or may
hereafter be adopted or amended, including, without limitation, Code of Maryland
Regulations, title 26, subtitle 10, chapters 2 through 12. As of the Term
Commencement Date, no underground storage tanks shall exist on the Land or
within the Project unless consented to in writing by Tenant, which consent shall
not be unreasonably withheld with respect to the Project. Landlord shall provide
all closure reports if required and issued by the Maryland Department of the
Environment for the tanks closed and removed on or before the Term Commencement
Date. From and after the Term Commencement Date, Landlord, at Landlord's
expense, shall remove, or cause to be removed, or cause to be brought into
compliance with all applicable laws any underground storage tanks located on the
Project not installed by or at the request of Tenant.

         38.6. Indemnification. Tenant hereby indemnifies and agrees to defend,
hold and save Landlord harmless from and against all claims arising from
Tenant's improper use, handling, or storage of Hazardous Materials at the
Project. However, Tenant shall not be responsible for existing contamination at
the Project, if any, and Tenant shall not have any obligation, responsibility,
or liability to Landlord for removing any Hazardous Materials released or
disposed of or otherwise introduced to the Project by any other tenants of the
Project or by Landlord or Landlord's employees, contractors, or agents or any
other party, other than Tenant's employees, agents or contractors. Landlord
hereby indemnifies and agrees



                                      -55-


<PAGE>   58
to defend, hold and save Tenant harmless from and against all actions, damages,
judgments, claims demands, and expenses (including counsel fees) incurred by
Tenant as a result of or in connection with any Hazardous Materials (i) existing
at the Project prior to the Term Commencement Date unless caused by Tenant, its
agents, employees, or contractors and (ii) that are not released or disposed of
or otherwise introduced to the Project by Tenant or Tenant's employees, agents,
or contractors. Landlord shall provide Tenant with a baseline Phase I
Environmental Site Assessment of the Project describing existing environmental
conditions certified in favor of Tenant upon Landlord's receipt of such Phase I
Environmental Site Assessment.

         38.7. Survival. Landlord's and Tenant's obligations under this Article
38 shall survive the expiration or earlier termination of the Lease. During any
period of time employed by Tenant or Landlord after the termination of this
Lease to complete the removal from the Demised Premises of any such Hazardous
Materials released or disposed of or otherwise introduced by Tenant or Tenant's
employees, agents, or contractors and the release and termination of any
licenses or permits restricting the use of the Demised Premises issued to Tenant
or to Landlord at Tenant's request, Tenant shall continue to pay the full Rent
in accordance with this Lease, which Rent shall be prorated daily.

39.      Right to Extend Term.

         Tenant shall have the right to extend the term of this Lease upon the
following terms and conditions:

         39.1. Tenant shall have two (2) consecutive rights (each, an "Extension
Right") to extend the term of this Lease for five (5) years each (each, an
"Extension Term") on the same terms and conditions as the Lease. During any
Extension Term, Annual Base Rent and Improvement Rent shall be payable at 102.5%
of the Annual Base Rent and Improvement Rent payable on the date immediately
preceding the commencement of such Extension Term. Annual Base Rent and
Improvement Rent shall be adjusted on the commencement of each Extension Term
and on each one (1) year anniversary of the commencement of such Extension Term
in accordance with Section 5.1.3.

         39.2. Extension Rights are personal to Digene Corporation and any
entity referred to in Section 24.3, and are not assignable separate and apart
from this Lease.

         39.3. Except as otherwise provided herein, Extension Rights are
conditional upon Tenant giving Landlord written notice of its election to
exercise each Extension Right at least one (1) year prior to the end of the
expiration of the initial term of the Lease or the expiration of any Extension
Term.

         39.4. Notwithstanding anything set forth above to the contrary,
Extension Rights shall not be in effect and Tenant may not exercise any of the
Extension Rights:



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<PAGE>   59
               39.4.1. during any period of time that Tenant is in default under
any provision of this Lease; or

               39.4.2. if Tenant has been in default under any provision of this
Lease three (3) or more times, whether or not the defaults are cured, during the
twelve (12) month period immediately prior to the date that Tenant intends to
exercise an Extension Right, whether or not the defaults are cured.

         39.5. The period of time within which any Extension Right may be
exercised shall not be extended or enlarged by reason of the Tenant's inability
to exercise the Extension Right because of the provisions of Section 39.4 above.

         39.6. The Extension Right shall terminate and be of no further force or
effect even after Tenant's due and timely exercise of an Extension Right, if,
after such exercise, but prior to the commencement date of an Extension Term,
(1) Tenant fails to timely cure any default by Tenant under this Lease; or (2)
Tenant has defaulted three (3) or more times during the period from the date of
the exercise of an Extension Right to the date of the commencement of the
Extension Term, whether or not such defaults are cured. In the event the
Extension Right terminates pursuant to this Section 39.6, the Lease shall
terminate on the Term Expiration Date or the expiration of the then applicable
Extension Term, if any, as applicable.

40.      Miscellaneous.

         40.1. Notice Upon Intent to Sell. In the event that Landlord shall
desire to sell all or any portion of the Building or the Project, Landlord shall
deliver to Tenant written notice of Landlord's intent to sell such property not
less than ten (10) days prior to publicly marketing the property.

         40.2. FDA Rules and Regulation. Notwithstanding anything to the
contrary set forth herein, nothing in this Lease shall be construed to require
Tenant to violate any Federal Drug Administration rule or regulation applicable
to Tenant or the Demised Premises and all obligations of Tenant and all rights
of Landlord hereunder shall be subject to any Federal Drug Administration rule
or regulation applicable to Tenant or the Demised Premises; provided, however,
that Tenant shall deliver to Landlord copies of any applicable rule, regulation
or correspondence of the Federal Drug Administration with respect to any
noncompliance of Tenant with this Lease necessitated by such rule, regulation or
correspondence.

         40.3. Real Estate Investment Trust. Notwithstanding anything to the
contrary set forth herein, nothing in this Lease shall be construed to require
Landlord to take any action or fail to take any action if, in the opinion of
Landlord's counsel, a copy of which shall be provided to Tenant, such action or
inaction would be likely to result in Landlord losing its status as a real
estate investment trust, as defined in Section 856 of the Internal Revenue Code
(as amended).



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<PAGE>   60
         40.4. Terms and Headings. Where applicable in this Lease, the singular
includes the plural and the masculine or neuter includes the masculine, feminine
and neuter. The section headings of this Lease are not a part of this Lease and
shall have no effect upon the construction or interpretation of any part hereof.

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

         40.6. Time. Time is of the essence with respect to the performance of
every provision of this Lease.

         40.7. Covenants and Conditions. Each provision of this Lease
performable by Tenant and Landlord shall be deemed both a covenant and a
condition.

         40.8. Consents. Whenever consent or approval of either party is
required, that party shall not unreasonably withhold, delay or condition such
consent or approval, except as may be expressly set forth to the contrary.

         40.9. Entire Agreement. The terms of this Lease are intended by the
parties as a final expression of their agreement with respect to the terms as
are included herein, and may not be contradicted by evidence of any prior or
contemporaneous agreement. The Basic Lease Provisions, general provisions, Work
Letter and Exhibits all constitute a single document and are incorporated
herein.

         40.10. Severability. Any provision of this Lease which shall provide to
be invalid, void, or illegal in no way affects, impairs or invalidates any other
provision hereof, and such other provisions shall remain in full force and
effect.

         40.11. Recording. Landlord shall not record this Lease or any short
form memorandum hereof without the consent of Tenant which may be withheld in
Tenant's sole discretion, except that no consent shall be required if such
recording is mandated by applicable law. If Tenant grants its consent to such
recordation or if such recordation is mandated by law, Tenant shall be
responsible for the cost of recording this Lease or any Memorandum of Lease,
including any transfer or other taxes incurred in connection with said
recordation.

         40.12. Impartial Construction. The language in all parts of this Lease
shall be in all cases construed as a whole according to its fair meaning and not
strictly for or against either Landlord or Tenant.

         40.13. Inurement. Each of the covenants, conditions and agreements
herein contained shall inure to the benefit of and shall apply to and be binding
upon the parties hereto and their respective heirs, legatees, devisees,
executors, administrators, successors, assigns, sublessees,



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<PAGE>   61
or any Person who may come into possession of said Demised Premises or any part
thereof in any manner whatsoever. Nothing in this Section 40.13 contained shall
in any way alter the provisions against assignment or subletting in this Lease
provided.

         40.14. Notices. Any notice, consent, demand, bill, statement, or other
communication required or permitted to be given hereunder must be in writing and
may be given by personal delivery and shall be deemed given when received or by
reputable overnight courier and shall be deemed given one business day after the
date on such courier's receipt of mailing addressed to Tenant at the Demised
Premises, or to Tenant or Landlord at the addresses shown in Section 2.1.11.
Either party may, by notice to the other given pursuant to this Section, specify
additional or different addresses for notice purposes.

         40.15. Maryland Jurisdiction. This Lease has been negotiated and
entered into in the State of Maryland and shall be governed by, construed and
enforced in accordance with the laws of the State of Maryland, applied to
contracts made in Maryland for Maryland domiciliaries to be wholly performed in
Maryland.

         40.16. Authority. That individual or those individuals signing this
Lease guarantee, warrant and represent that said individual or individuals have
the power, authority and legal capacity to sign this Lease on behalf of and to
bind all entities, corporations, partnerships, joint venturers or other
organizations and/or entities on whose behalf said individual or individuals
have signed.

         40.17. Guaranty. Certain of the obligations of Landlord hereunder have
been guaranteed by Alexandria Real Estate Equities, Inc., a Maryland corporation
("ARE") pursuant to that certain Performance Guaranty Agreement of even date
herewith (the "Guaranty") in favor of Digene Corporation. As provided therein,
the Guaranty expires on the first anniversary following Substantial Completion
and is personal to Digene Corporation and the entities referred to in Section
24.3.

41.      Defined Terms

         As used in this Lease, the following terms have the meaning defined in
this Section 41.

         41.1. "ADA" refers to the Americans With Disabilities Act, 42 U.S.C.
Sec. 12101, et seq., together with regulations promulgated pursuant thereto.

         41.2. "Assignment Date" shall mean the date on which Tenant desires a
proposed assignment or sublease of the Demised Premises to be effective.

         41.3. "Assignment Notice" shall mean a notice containing information
(including references) concerning the character of the proposed assignee or
sublessee, the Assignment Date, any ownership or commercial relationship between
Tenant and the proposed assignee or



                                      -59-


<PAGE>   62
sublessee, and the consideration and all other material terms and conditions of
the proposed assignment or sublease.

         41.4. "BOMA Standard" shall mean the 1996 Standard Method for Measuring
Floor Area in Office Buildings as adopted by the Building Owners and Managers
Association.

         41.5. [Intentionally Omitted].

         41.6. [Intentionally Omitted].

         41.7. "Expansion Space" shall mean rentable space, if any, in other
buildings in the Project which Landlord may, but shall have no obligation to,
construct from time to time.

         41.8. "Force-Majeure Delays" shall mean delays due to strikes,
lockouts, acts of God, enemy action, war, civil commotion, action or inaction by
any governmental agency or office not resulting from the failure of either party
hereto to timely comply with all procedures required by such agency or office
(including, without limitation, the failure of either party hereunder to receive
applicable governmental approvals or permits), casualty, weather conditions and
the inability to obtain labor or materials as a result of any of the foregoing.

         41.9. "Hazardous Material" shall mean any pollutant, contaminant,
hazardous or toxic substance, material or waste, including, without limitation,
those that are or become regulated by any local governmental authority, the
State of Maryland, or the United States government. The term "Hazardous
Material" includes, without limitation, any material or substance which is (i)
designated as a "hazardous substance" pursuant to Section 311 of the Federal
Water Pollution Control Act (33 U.S.C. Section 1317), (ii) defined as a
"hazardous waste" pursuant to Section 1004 of the Federal Resource Conversation
and Recovery Act, 42 U.S.C. Section 6901, et. seq. (42 U.S.C. Section 6903),
(iii) defined as a "hazardous substance" pursuant to Section 101 of the
Comprehensive Environmental Response Compensation and Liability Act, 42 U.S.C.
Section 9601 et. seq. (42 U.S.C. Section 9601), (iv) defined as "oil" pursuant
to Section 4-401(g) of the Maryland Environmental Code Annotated (1993), or (v)
designated as "hazardous substance" or "hazardous waste" pursuant to Maryland
Environmental Code Ann., Title 7, Subtitle 2 (1993), all as amended from time to
time and together with the rules and regulations promulgated thereunder.

         41.10. "Hazardous Materials List" shall mean a list identifying each
type of Hazardous Material to be present on the Demised Premises and setting
forth any and all governmental approvals or permits required in connection with
the presence of such Hazardous Materials on the Demised Premises.

         41.11. "Improvement Rent" shall mean the amount determined in
accordance with Section 5.3.



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<PAGE>   63
         41.12. [Intentionally Omitted.]

         41.13. [Intentionally Omitted.]

         41.14. "Landlord's Work" shall have the meaning set forth in the Work
Letter.

         41.15. "Person" shall mean an individual, partnership, corporation,
limited liability company or any other legally existing entity.

         41.16. "Project Architect" shall have the meaning ascribed to such term
in the Work Letter.

         41.17. "Project Common Areas" shall mean all portions of the Project
which are for the non-exclusive use of tenants of the buildings at the Project
as shown on the site plan attached as Exhibit "C".

         41.18. "Rentable Area" shall mean the total of rentable area calculated
in accordance with BOMA Standard.

         41.19. "Rules and Regulations" shall mean the rules and regulations
adopted by Landlord and attached hereto as Exhibit "I" and to other reasonable
and nondiscriminatory rules and regulations as are hereafter promulgated by
Landlord in its discretion.

         41.20. "Substantially Complete(d)" and "Substantial Completion" shall
mean latest of (i) the date of issuance of a temporary certificate of occupancy
for the Demised Premises subject only to such minor work as would not
unreasonably interfere with Tenant's occupancy and use of the Demised Premises
for the purposes for which it is to be used, (ii) the date Tenant receives a
Certificate of Substantial Completion in the form of the American Institute of
Architects document G704 executed by the Project Architect and the TI Architect
and the General Contractor (as required by and defined in the Work Letter
addressed to Tenant), and (iii) the date the Land constitutes a legally
subdivided parcel assessed for tax purposes separate and apart from the
remainder of the Project; provided, however, that validation by the Federal Drug
Administration or other similar governmental licensing of the Demised Premises
for Tenant's use shall in no event be deemed a condition to Substantial
Completion.

         41.21. "Target Term Commencement Date" shall mean August 1, 1999.

         41.22. "Tenant-Caused Delays" shall mean, collectively, delays caused
by (i) Tenant's requests for Changes (as defined in the Work Letter), (ii)
Tenant's failure to timely comply with any of Tenant's obligations under the
Work Letter, including, without limitation, failure to timely review and approve
any documents which Tenant has an obligation to review and approve, and (iii)
any other delay which is deemed to be a Tenant-Caused Delay under this Lease or
the Work Letter.



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<PAGE>   64
         41.23. "Tenant Improvement Allowance" shall mean Tenant's allowance of
$25.00 per square foot of Rentable Area, subject to increase pursuant to Section
4.10.

         41.24. "Tenant Improvements" has the meaning set forth in the Work
Letter.

         41.25. "Tenant's Work" shall have the meaning ascribed to such term in
the Work Letter

         41.26. "Tenant's Pro Rata Share of Building" shall mean one hundred
percent 100%.

         41.27. "Tenant's Pro Rata Share of Project" shall mean a fraction, the
numerator of which is the Rentable Area of the Demised Premises and the
numerator of which is the Rentable Area of the Project, subject to the terms of
Section 6.6.

         41.28. "Termination Amount" shall mean an amount equal to the present
value of all Annual Base Rent, Improvement Rent and Additional Rent anticipated
to come due to during the period from the fifth anniversary of the Effective
Date through the Term Expiration Date (had the Lease not been terminated),
computed at an eight percent (8%) per annum discount rate compounded monthly.

         41.29. "Usable Area" shall mean the usable area calculated in
accordance with the BOMA Standard.

         41.30. "Work Letter" shall mean the work letter attached hereto as
Exhibit "E".



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<PAGE>   65
         IN WITNESS WHEREOF, the parties hereto have executed this Lease as of
the date first above written.

                                            "TENANT"

                                            DIGENE CORPORATION,

                                            a Delaware corporation

                                            By: /s/ Charles M. Fleischman
                                               _________________________________

                                                 Its:      CFO & COO
                                                      __________________________

                                            "LANDLORD"

                                            ARE-METROPOLITAN GROVE I, LLC.
                                            a Delaware limited liability company

                                            By:   ALEXANDRIA REAL ESTATE
                                                  EQUITIES, L.P., a Delaware
                                                  limited partnership, managing
                                                  member

                                                  By:  ARE-QRS CORP., a
                                                       Maryland corporation,
                                                       general partner

                                                       By: /s/ Alan D. Gold
                                                           _____________________

                                                       Its:    President
                                                           _____________________



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<PAGE>   66
                               EXHIBITS/SCHEDULES

Exhibit "A"   Land

Exhibit "B"   Demised Premises

Exhibit "C"   Project

Exhibit "D"   Acknowledgment of Term Commencement Date

Exhibit "E"   Work Letter

Exhibit "F"   Acknowledgment of Rentable Area and Pro Rata Share

Exhibit "G"   Tenant Property

Exhibit "H"   Estoppel Certificate

Exhibit "I"   Rules and Regulations

Exhibit "J"   Subordination, Nondisturbance and Attornment Agreement

Exhibit "K"   Hazardous Materials List

Schedule 1    Milestone Events and Dates



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