Document:

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                                                                 Exhibit 10.1.11
                                  OFFICE LEASE

             SOFI-IV SIM OFFICE INVESTORS II, LIMITED PARTNERSHIP

                                    Landlord

                                       and

              Advanced Telecommunications, Inc. a Delaware corp.

                                     Tenant

                             Dated: December 1, 1999
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TABLE OF CONTENTS

                                TABLE OF CONTENTS

ARTICLE 1     SUMMARY OF BASIC TERMS

ARTICLE 2     DELIVERY, TERM AND CONSTRUCTION
    2.1       Term
    2.2       Memorandum
    2.3       Area Measurement
    2.4       Condition

ARTICLE 3     USE OF PREMISES
    3.1       Permitted Uses
    3.2       Insurance Restrictions
    3.3       Improvements
    3.4       Prohibitions
    3.5       Common Areas
    3.6       Rules and Regulations
    3.7       Compliance with Law
    3.8       Audit
    3.9       Parking
   3.10       Keys, Locks and Access Cards

ARTICLE 4     SECURITY DEPOSIT AND GUARANTIES

ARTICLE 5     RENT
    5.1       Base Rent
    5.2       Late Charges and Interest
    5.3       Excise Taxes
    5.4       Obligations are Rent
    5.5       Proration

ARTICLE 6     OPERATING COSTS
    6.1       Tenant's Share
    6.2       Estimates
    6.3       Annual Reconciliation
    6.4       Partial Year Proration, Variable Cost Adjustment
    6.5       Operating Costs
    6.6       Exclusions

ARTICLE 7     TAXES

ARTICLE 8     INSURANCE AND INDEMNITY
    8.1       Insurance Policies
    8.2       Policy Requirements
    8 3       Evidence of Coverage
    8 4       Indemnity and Exculpation
    8.5       Landlords Policies

ARTICLE 9     FIRE AND CASUALTY
    9.1       Termination Rights
    9.2       Restoration
    9.3       Abatement
    9.4       Demolition of Project
    9.5       Agreed Remedies

ARTICLE 10    CONDEMNATION
   10.1       Automatic Termination
   10.2       Optional Termination
   10.3       Award

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ARTICLE 11    MAINTENANCE
   11.1       By Tenant
   11.2       By Landlord

ARTICLE 12    UTILITIES

ARTICLE 13    LANDLORD RIGHT OF ENTRY

ARTICLE 14    SIGNS

ARTICLE 15    TENANT ALTERATIONS
   15.1       Tenant Alterations
   15.2       Tenant Installations
   15.3       Mechanics Liens

ARTICLE 16    ASSIGNMENT AND SUBLETTING
   16.1       Consent Required
   16.2       Requests for Approval
   16.3       Continued Responsibility
   16.4       Excess Proceeds
   16.5       Limitations
   16.6       No Waiver
   16.7       Transfer by Landlord

ARTICLE 17    SUBORDINATION AND A1TORNMENT
   17.1       Subordination
   17.2       Lender Protection
   17.3       Documentation
   17.4       Other Transactions

ARTICLE 18    ESTOPPEL CERTIFICATES

ARTICLE 19    QUIET ENJOYMENT

ARTICLE 20    SURRENDER AND HOLDOVER
   20.1       Surrender
   20.2       Holdover

ARTICLE 21    BREACH, DEFAULT, AND REMEDIES
   21.1       Default
   21.2       Remedies
   21.3       Subtenancies

ARTICLE 22    LANDLORD LIABILITY

ARTICLE 23    NOTICES

ARTICLE 24    BROKERAGE

ARTICLE 25    RELOCATION

ARTICLE 26    GENERAL
   26.1       Severability
   26.2       No Waiver
   26.3       Effect of Payment
   26.4       Delay
   26.5       Lender Notice
   26.6       No Offer

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   26.7       Successors
   26.8       Integration
   26.9       Waiver of Jury Trial
  26.10       Governing Law
  26.11       Deadlines Enforceable
  26.12       Counterparts
  26.13       Additional Provisions

ARTICLE 27      SERVICES

     A.       Landlord's Obligations
     B.       Electrical Service
     C.       Restoration of Service/Tenant Self-Help Remedy
     D.       Generator & HVAC Access

ARTICLE 28    RISERS & CONDUIT ACCESS

ARTICLE 29    BATTERY INSTALLATION

ARTICLE 30    GROUNDING RISER

ARTICLE 31    ANTENNAE

ARTICLE 32    FIRE PROTECTION & LIFE SAFETY

ARTICLE 33    HAZARDOUS SUBSTANCES

ARTICLE 34    EXPRESS WAIVER OF LANDLORD'S LIEN

ARTICLE 35    ALLOWABLE USE OF CERTAIN HAZARDOUS MATERIALS

EXHIBITS

EXHIBIT A -   THE PREMISES
EXHIBIT A-1 - FLOOR PLAN
EXHIBIT B -   CONSTRUCTION PROVISIONS
EXHIBIT C -   RULES AND REGULATIONS

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OFFICE LEASE

SOFI-IV SIM OFFICE INVESTORS II LIMITED PARTNERSHIP, an Delaware limited
partnership ("Landlord"), hereby leases the Premises described below, for the
Term and on the terms and conditions set forth in this Lease, to:

Advanced Telecommunications, Inc. a Delaware corp.

                                                                     ("Tenant").

ARTICLE I SUMMARY OF BASIC TERMS

1.1  The Premises: Suite #500 in the Building consisting of approximately 6,028
     square feet of rentable area as illustrated on the attached Exhibit A. A
     floor plan for the floor(s) on which the Premises is located is attached as
     Exhibit A-1.

1.2  The Building: The building is located at 2600 North Central Avenue,
     Phoenix, Arizona.

1.3  "Project" means the Building identified in Section 1.2, and all lands and
     facilities used in connection with the Building as reasonably determined
     from time to time by Landlord. The Project consists of approximately
     322,000 square feet of rentable area.

1.4  Names of Guarantor & None

1.5  Security Deposit: $12,000.00.

1.6  The Term: Ten (10) years and four (4) months, beginning on the Commencement
     Date and ending on the Expiration Date.

1.7  Commencement and Expiration Dates: January 15, 2000, and May 15, 2010,
     respectively, subject to the provisions of Exhibit

B.

1.8  Base Rent:

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Lease Year    Annual Base Rent      Base Rent Per Square Foot  Monthly Base Rent
--------------------------------------------------------------------------------
   1           $120,560.00               $20.00/sq. ft.          $ 10,046.67
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   2           $124,176.80               $20.60/sq. ft.           $10,348.07
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   3           $127,914.16               $21.22/sq. ft.           $10,659.51
--------------------------------------------------------------------------------
   4           $131,772.08               $21.86/sq. ft.           $10,981.01
--------------------------------------------------------------------------------
   5           $135,750.56               $22.52/sq. ft.           $11,312.55
--------------------------------------------------------------------------------
   6           $139,849.60               $23.20/sq. ft.           $11,654.13
--------------------------------------------------------------------------------
   7           $144.069.20               $23.90/sq. ft.           $12,005.77
--------------------------------------------------------------------------------
   8           $148,409.36               $24.62/sq. ft.           $12,367.45
--------------------------------------------------------------------------------
   9           $152,870.08               $25.36/sq. ft.           $12,739.17
--------------------------------------------------------------------------------
   10          $157,451.36               $26.12/sq. ft.           $13,120.95
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1.9 Tenant's Proportionate Share: 1.87%, consisting of the proportion that the
rentable area of the Premises bears to the rentable area of the Project.

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1.10 Base Year: 2000.

1.11 Description of Tenant's Business: Executive and general office use, the
installation, operation and maintenance of equipment and facilities in
connection with Tenant's telecommunication business, including but nor limited
to telecommunications switch.

1.12 Normal Business Hours: 7:00 a.m. to 6:00 p.m., Monday through Friday, 8 00
a.m. to 1:00 p.m. on Saturday.

1.13 Tenant Improvement Allowance: $5.OO per rentable square foot ($30,140 00).

1.14 Tenant's Address for Pre-occupancy Notices:     730 2nd Ave. South
                                                     # 1200
                                                     Minneapolis. MN 55402

1.15 Landlord's Notice Address:     c/o Scottsdale Property Management 97, L.L.C
                                    9495 E. San Salvador, Suite 100
                                    Scottsdale, AZ 85258

1.16 Tenant's designated broker:      Eric Ham, TELECOM Real Estate Services

11.7 Landlord's designated broker:    Scottsdale Property Management 97, L.L.C.

ARTICLE 2 DELIVERY, TERM AND CONSTRUCTION

2.1 Term. The Term of this Lease, and the dates of commencement and expiration
of the Term, are set forth in Sections 1.6 and 1.7

2.2 Memorandum. At the request of either party at any time following initial
occupancy of the Premises by Tenant, Landlord and Tenant shall execute a written
memorandum reflecting the date of initial occupancy and confirming the
Commencement Date and Expiration Date

2.3 Area Measurement. "Rentable Area" means area measured in accordance with
American National Standard Z65.1-1980, as published by BOMA International.

2.4 Condition. Landlord shall have no obligation to make any improvements or
alterations to the Premises or the Building whatsoever, and Tenant accepts the
Premises in an AS IS condition, with all faults. Notwithstanding the foregoing,
if an Exhibit C is attached to this Lease, Landlord shall cause improvements to
be constructed and alterations to be made in the Premises in accordance with the
provisions of Exhibit B

ARTICLE 3 USE OF PREMISES

3.1 Permitted Uses. Tenant may use and occupy the Premises for the purposes set
forth in Section 1.11 and for no other purpose whatsoever without Landlord's
prior written consent. Tenant shall not use the Premises for any purpose in
violation of exclusive rights granted by Landlord from time to time to any other
Tenant; provided, however, that Landlord shall not grant any exclusive right
that would prevent Tenant from conducting its business as described in Section
1.11.

3.2 Insurance Restrictions. Tenant shall not perform any act which would cause
the cancellation of any insurance policies related to the Project. Tenant shall
reimburse Landlord for any increases in insurance premiums paid by Landlord
directly related to the nature of Tenant's use of the Premises or the nature of
Tenant's business.

3.3 Improvements. If solely due to the nature of Tenant's use of the Premises,
improvements or alterations are necessary to comply with any requirements
imposed by Law or with the requirements of insurance carriers, Tenant shall pay
the entire cost of the improvements or alterations.

3.4 Prohibitions. Tenant shall not cause or maintain any nuisance in or about
the Premises and shall keep the Premises free of debris, rodents, vermin and
anything of a dangerous, noxious or offensive nature or which would create a
fire hazard (through undue

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load on electrical circuits or otherwise) or undue vibration, noise or heat.
Tenant shall not cause the safe floor loading capacity to be exceeded. Tenant
shall not disturb or interfere with the quiet enjoyment of the premises of any
other tenant

3.5 Common Areas. All of the portions of the Project made available by Landlord
for use in common by tenants and their employees and invitees ("Common Areas")
at all times shall remain subject to Landlord's exclusive control and Landlord
shall be entitled to make such changes in the Common Areas as it deems
appropriate. Landlord shall have the right at any time to change the arrangement
and/or locations of entrances, or passageways, doors and doorways, and
corridors, windows, elevators, stairs, toilets or other public parts of the
Building and to change the name, number or designation by which the Building or
the Project is commonly known.

3.6 Rules and Regulations. Tenant shall comply and shall cause its employees to
comply with the rules and regulations for the Project. The current rules and
regulations are attached as Exhibit C. Landlord from time to time by notice to
Tenant may amend the rules and regulations and establish other reasonable
non-discriminatory rules and regulations for the Project

3.7 Compliance with Law. Without in any manner limiting any other provision of
this Lease, Tenant hereby represents and warrants and agrees for the full term
of any obligations under this Lease:

     (a) to comply fully with all federal, state and local laws, rules, orders,
or regulations pertaining to health or the environment ("Environmental Laws"),
including, without limitation, the comprehensive Environmental Response,
Compensation, and Liability Act of 1980, as amended ("CERCLA") and the Resource
Conservation and Recovery Act of 1987, as amended ("RCRA").

     (b) that Tenant will not dispose of nor permit or acquiesce in the disposal
of any waste (including, but not limited to, and paints, solvents, or paint
thinners) products on, under or around the Premises.

     (c) to defend, indemnify and hold harmless Landlord for any and all costs,
claims, demands, damages including attorneys' fees and court costs and
investigatory and laboratory fees, related to any breach of this Lease,
including, without limitation, any adverse health or environmental condition
(including without limitation any violation of Environmental Laws) occurring
during the term of this Lease. This indemnification to Landlord shall survive
the termination of the Lease.

     (d) comply with all reporting obligations imposed under the Federal
Emergency Planning and Community Right to Know Act of 1986 and any similar state
or local laws, rules or regulations.

     (e) comply with all pretreatment requirements imposed by law with respect
to the disposal of waste or effluent into the sanitary sewer system;

     (f) prevent any dumping, spillage, leakage or runoff of substances
regulated by Environmental Laws ("Regulated Substances") into dry wells, storm
drains, water retention areas, Common Areas or any areas where such substances
could be absorbed into the soil;

     (g) obtain and maintain all permits required by federal, state or local
laws, rules or regulations;

     (h) prepare, and upon request provide a copy to Landlord of, all response
plans required by applicable law, and

     (i) not keep, store, or use within the Premises any Regulated Substances
except small quantities that are reasonably necessary for Tenant's business and
customarily associated with office usage, such as copier supplies.

3.8 Audit. At any time and from time to time, Landlord may retain an
environmental consultant or engineer to conduct an audit or environmental
assessment of the Premises and Tenant's compliance with applicable laws, rules
and regulations. Tenant shall extend its full cooperation with the audit or
investigation If Tenant is found not to be substantially in compliance with
applicable law, all reasonable costs associated with the audit or assessment
shall be paid by Tenant to Landlord upon demand; otherwise all costs shall be
borne by Landlord. In addition, Tenant, at Landlord's request from time to time,
shall complete such questionnaires and provide such information with respect to
Tenant's activities and operations on the Premises as Landlord shall reasonably
require.

3.9 Parking . Tenant shall lease the following parking spaces:

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        # of Spaces     Parking Area       Price per Space         Total Price
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       Up to 6        open unreserved      @ then current
                                             bldg rates
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3.10 Keys, Locks and Access Cards.

     (a) Landlord shall furnish Tenant two keys for each corridor door entering
the Premises. Additional keys will be furnished at a charge by Landlord on an
order signed by Tenant or Tenant's authorized representative. All such keys
shall remain the property of Landlord No additional locks shall be allowed on
any door of the Premises without Landlord's permission. and Tenant shall not
make, or permit to be made any duplicate keys. Upon termination of this Lease,
Tenant shall surrender to Landlord all keys of the Premises, and give to
Landlord the combination of all locks for safes, safe cabinets and vault doors,
if any, in the Premises

     (b) Landlord shall furnish tenant with security access cards for the
Building ("Access Cards"). Access Cards will be furnished at a reasonable charge
by Landlord on an order signed by Tenant or Tenant's authorized representative.
A portion of the charge for the Access Cards may constitute a deposit, the
balance of which shall compensate Landlord for costs, record keeping and other
administrative items in respect of the Access Cards. All such orders shall be
treated as confidential. All such cards shall remain the property of Landlord.
Replacement Access Cards shall be subject to a reasonable charge. Landlord shall
charge Tenant a reasonable transfer fee in connection with a change in the
registration of an Access Card Tenant shall promptly notify Landlord of a lost
Access Card, UNDER NO CIRCUMSTANCES shall tenant label, or in any other way
identify, any Access Cards as to the name of the Building, address of the
Building, or include tenant's personal or company name. Upon termination of any
officer, employee, or any other authorized representative of Tenant, any Access
Card to said person shall be surrendered to Tenant immediately. It shall be the
Tenant's obligation to notify Landlord of all terminated access privileges as
soon as possible following such action. Upon termination of this Lease, Tenant
shall surrender to Landlord all registered Access Cards. The card deposit
portion of the charge paid by Tenant, if any, will be refunded by Landlord
within thirty days, provided all Access Cards are in a reusable condition.

ARTICLE 4 SECURITY DEPOSIT

Upon execution of this Lease Tenant shall deposit with Landlord a security
deposit in the amount set forth in Section 1.5 to secure Tenant's performance of
this Lease. The deposit shall not bear interest, shall not be required to be
maintained in a separate account, and shall be returned, less any unpaid claims
against Tenant, upon the expiration of this Lease and the surrender of
possession of the Premises, to Tenant or the last assignee of Tenant's interest
If Tenant has not been in default under the terms of this Lease for the first
thirty-sixth (36th) months of the lease term, then Landlord shall apply the
Security Deposit towards the rental due for the thirty-seventh (37th) month. If
a Tenant default occurs after the thirty-sixth (36th) month, then upon written
notice from Landlord, Tenant will deposit with Landlord, within thirty days of
said notice, a "new" security deposit of S 12,000.00

ARTICLE 5 RENT

5.1 Base Rent. Tenant shall pay to Landlord, in advance, on the first day of
each calendar month, beginning on the first day of the fourth full calendar
month following the Commencement Date ("Rent Commencement Date"), Base Rent in
the amount set forth in Section 1.8.

5.2 Late Charges and Interest. Tenant shall pay to Landlord a late charge equal
to ten percent (10%) of the amount due if any installment of Base Rent or if any
other amount payable under this Lease is not received by Landlord within five
(5) days after the due date therefor. The parties agree that such late charge
represents a fair and reasonable estimate of the costs Landlord will incur by
reason of such late payment and that such late charge constitutes liquidated
damages to compensate Landlord for costs and inconveniences of special handling
and disruption of cash flow. The assessment or collection of a late charge shall
not constitute the waiver of a default and shall not bar the exercise of other
remedies for nonpayment. In addition to the late charge, all amounts not paid
within ten days after the date due shall bear interest from the date due (i)
until the happening of an Event of Default, at the rate of 12% per annum and
(ii) thereafter, at the rate set forth in Section 2.1.2.

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5.3 Excise Taxes. Tenant shall pay to Landlord all rental, sales, use,
transaction privilege, or other excise tax levied or imposed upon, or measured
by, any amount payable by Tenant under this Lease.

5.4 Obligations Are Rent. All amounts payable to Landlord under this Lease
constitute rent and shall be payable without notice, demand, deduction or offset
to such person and at such place as Landlord may from time to time designate by
written notice to Tenant

5.5 Proration. Base Rent payable with respect to a period consisting of less
than a full calendar month shall be prorated.

ARTICLE 6 OPERATING COSTS

6.1 Tenant's Share. Tenant shall pay to Landlord Tenant's Proportionate Share of
Operating Costs for each calendar year in excess of the Operating Costs for the
Base Year as set forth in Section 1.10.

6.2 Estimates. From time to time Landlord shall by written notice specify
Landlord's estimate of Tenant's obligation under Section 6.1. Tenant shall pay
one-twelfth of the estimated annual obligation on the first day of each calendar
month.

6.3 Annual Reconciliation. Within 120 days after the end of each calendar year,
Landlord shall provide to Tenant a written summary of the Operating Costs for
the calendar year, determined on an accrual basis and broken down by principal
categories of expense. The statement also shall set forth Tenant's Proportionate
Share of Operating Costs and shall show the amounts paid by Tenant on account.
Any difference between Tenant's obligation and the amounts paid by Tenant on
account shall be paid or refunded, as the case may be, within fifteen days after
the statement is provided. Late delivery of the annual statement of Operating
Costs shall not relieve Tenant of any obligation with respect to payment of
Tenant's Proportionate Share of the Operating Costs

6.4 Partial Year Proration; Variable Cost Adjustment. During the first and last
years of the Term, Tenant's responsibility for Operating Costs shall be adjusted
in the proportion that the number of days of that calendar year during which the
Lease is in effect bears to 365. Tenant's obligations under this Article 6 for
the payment of Operating Costs during the Lease Term, including the payment of
any deficiency following receipt of the annual statement under Section 6.3,
shall survive the expiration or termination of this Lease.

6.5 "Operating Costs" consist of all costs of operating, maintaining and
repairing the Project, including, without limitation, the following:

     (a) Premiums for property, casualty, liability, rent interruption or other
insurance.

     (b) Salaries, wages and other amounts paid or payable for personnel
including the Project manager, superintendent, operation and maintenance staff,
and other employees of Landlord involved in the maintenance and operation of the
Project, including contributions and premiums towards fringe benefits,
unemployment and workers compensation insurance, pension plan contributions and
similar premiums and contributions and the total charges of any independent
contractors or managers engaged in the repair, care, maintenance and cleaning of
any portion of the Project.

     (c) Cleaning, including sweeping of parking areas and removal of snow and
ice.

     (d) Landscaping, including irrigating, trimming, mowing, fertilizing,
seeding, and replacing plants.

     (e) Utilities, including fuel, gas, electricity, water, sewer, telephone,
and other services.

     (f) Maintaining, operating, repairing and replacing equipment.

     (g) Other items of repair or maintenance of the Project.

     (h) Policing and security.

     (i) The cost of the rental of any equipment and the cost of supplies used
in the maintenance and operation of the Project.

     (j) Audit fees and the cost of accounting services incurred in the
preparation of statements referred to in this Lease and financial statements,
and in the computation of the rents and charges payable by tenants of the
Project.

     (k) Costs of capital expenditures incurred for the purpose of reducing
Operating Costs, and costs of improvements, repairs, or replacements which
otherwise constitute Operating Costs under this Article but which are properly
charged to capital

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accounts shall not be included in Operating Costs in a single year but shall
instead be amortized over their useful lives, as determined by the Landlord in
accordance with generally accepted accounting principles, and only the annual
amortization amount shall be included in Operating Costs.

     (l) A fee for the administration and management of the Project appropriate
to the nature of the Project as reasonably determined by the Landlord from time
to time.

     (m) Costs of alterations or modifications to the Project necessary to
comply with requirements of applicable law; and

     (n) General and special real and personal property taxes and assessments
for the Project and expenses incurred in efforts to reduce taxes or assessments.

6.6 Exclusions. Notwithstanding anything to the contrary in Section 6.5,
"Operating Costs" shall not include:

     (a) Amounts reimbursed by other sources, such as insurance proceeds,
equipment warranties, judgments or settlements.

     (b) Utilities or other expenses paid directly by tenants to suppliers or
paid by tenants to Landlord for separately metered or special services such as
after-hours air conditioning services.

     (c) Ground rents.

     (d) Payments on any mortgage or other encumbrance.

     (e) Construction of tenant improvements.

     (f) Replacements (but not repairs) of structural elements.

     (g) Leasing commissions.

     (h) General overhead and administrative expenses of Landlord not directly
related to the operation of the Project

ARTICLE 7 TAXES

7.1 Landlord shall pay before delinquent all general and special real property
taxes assessed or levied on the Project, subject to reimbursement under Article
6.

7.2 Tenant shall pay before delinquent all taxes levied or assessed upon,
measured by, or arising from (a) the conduct of Tenant's business; (b)
Tenant's leasehold estate; or (c) Tenant's property.

ARTICLE 8 INSURANCE AND INDEMNITY

8.1 Insurance Policies. Tenant shall, at its expense, take out and keep in full
force and effect the following insurance:

     (a) All-risk property insurance including sprinkler leakage in an amount
equal to the full replacement cost of all property owned by Tenant

     (b) Business interruption insurance with a limit sufficient to insure not
less than a six month loss of income.

     (c) Plate glass insurance coverage

     (d) Comprehensive liability insurance applying to the use and occupancy of
the Premises and the business operated by Tenant, including coverage for
"premises/operations", "products and completed operations", and "blanket
contractual" liabilities, written on an occurrence basis with limits not less
than $1,000,000, naming Landlord, its agents, affiliates and contract property
manager as additional insureds.

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        (e) At all times during the Lease Term, Tenant shall procure and
maintain workers' compensation insurance in accordance with applicable law and
employer's liability insurance with a limit not less than $1,000,000 bodily
injury each accident; $1,000,000 bodily injury by disease - each person; and
$1,000,000 bodily injury by disease - policy limit.

8.2 Policy Requirements. Tenant's insurance policies shall:

     (a) where applicable, contain the mortgagee's standard mortgage clause and
in any event a waiver of any subrogation rights which Tenant's insurers may have
against Landlord and against those for whom the Landlord is in law responsible;

     (b) be taken out with insurers reasonably acceptable to Landlord and be in
a form satisfactory from time to time to Landlord;

     (c) be non-contributing and apply as primary and not as excess to, any
other insurance available to the Landlord;

     (d) not be invalidated with respect to the interests of the Landlord and
the holder of any encumbrance on the Project by reason of any breach or
violation by Tenant of any warranties, representations, declarations or
conditions contained in the policies;

     (e) contain an undertaking by the insurers to notify the Landlord, and the
holder of any encumbrance on the Project designated by Landlord, in writing not
less than thirty days prior to any material change, cancellation or termination;
and

     (f) be satisfactory in form, substance, limits, deductibles and retentions
to Landlord

8.3 Evidence of Coverage. Tenant shall deliver to Landlord certificates of
insurance or, if required by Landlord, certified copies of each such insurance
policy: (a) as soon as practicable after the placing of the required insurance
and (b) periodically thereafter before expiration, renewal or replacement of the
policies then in force. No review or approval of any such insurance certificate
by Landlord shall derogate or diminish Landlord's rights or Tenant's
obligations. Tenant shall not take possession of the Premises without having
complied with the requirements of this Section.

8.4 Indemnity and Exculpation. Tenant shall defend, indemnify and hold Landlord
harmless, regardless of any negligence imputed to Landlord as owner of the real
property involved in an injury, from and against any and all loss, claims,
actions, damages, liability and expense in connection with loss of life,
personal injury, damage to property' or any other loss or injury whatsoever
arising directly or indirectly from or out of this Lease, or any occurrence in,
upon or at the Premises, or the occupancy or use by the Tenant of the Premises,
or any act or omission of Tenant, its agents, servants, employees or invitees.
Tenant shall not be required, however, to indemnify Landlord against a claim
arising from Landlord's active negligence or willful misconduct Landlord shall
not be liable and Tenant hereby waives all claims for any damage to any property
in or about the Premises or the Project or injury or inconvenience to Tenant's
business, by or from any cause whatsoever (including without limiting the
foregoing, rain or water leakage of any character from the roof, windows, walls,
basement, pipes, plumbing works or appliances). Tenant acknowledges that it is
protecting itself against loss by maintaining appropriate insurance coverage.

8.5 Landlord's Policies. No insurable interest is conferred upon Tenant under
any policies of insurance carried by Landlord, and Tenant shall not be entitled
to share or receive proceeds of any insurance policy carried by Landlord.

ARTICLE 9 FIRE AND CASUALTY

9.1 Termination Rights. If all or part of the Premises is rendered untenantable
by damage from fire or other casualty which in Landlord's opinion cannot be
substantially repaired (employing normal construction methods without overtime
or other premium) under applicable laws and governmental regulations within 180
days from the date of the fire or other casualty, then either Landlord or Tenant
may elect to terminate this Lease as of the date of such casualty by written
notice delivered to the other not later than ten days after notice of such
determination is given by Landlord.

9.2 Restoration. If in Landlord's opinion the damage caused by the fire or
casualty can be substantially repaired (employing normal construction methods
without overtime or other premium) under applicable laws and governmental
regulations within 180 days from the date of the fire or other casualty, or if
neither party exercises its right to terminate under Section 9.1, Landlord
shall, but only to the extent that insurance proceeds are available therefor,
repair such damage other than damage to furniture, chattels or trade fixtures
which do not belong to the Landlord, which shall be repaired forthwith by Tenant
at its own expense.

9.3 Abatement. During any period of restoration, the Base Rent payable by Tenant
shall be proportionately reduced to the extent that the Premises are thereby
rendered untenantable from the date of casualty until completion by Landlord of
the repairs to the

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Premises (or the part thereof rendered untenantable) or until Tenant again uses
the Premises (or the part thereof rendered untenantable) in its business,
whichever first occurs.

9.4 Demolition of Project. Notwithstanding anything to the contrary in Section
9.1, if all or a substantial part (whether or not including the Premises) of the
Building is rendered untenantable by damage from fire or other casualty to such
a material extent that in the opinion of Landlord the Project must be totally or
partially demolished, whether or not to be reconstructed in whole or in part,
Landlord may elect to terminate this Lease as of the date of the casualty (or on
the date of notice if the Premises are unaffected by such casualty) by written
notice delivered to Tenant not more than sixty days after the date of the fire
or casualty.

9.5 Agreed Remedies. Except as specifically provided in this Article, there
shall be no reduction of rent and Landlord shall have no liability to Tenant
by reason of any injury to or interference with Tenant's business or property
arising from fire or other casualty, howsoever caused, or from the making of
any repairs resulting therefrom in or to any portion of the Project or the
Premises. Tenant waives any statutory or other rights of termination by
reason of fire or other casualty, it being the intention of the parties to
provide specifically and exclusively in this Article for the rights of the
parties with respect to termination of this Lease as a result of a casualty.

ARTICLE 10 CONDEMNATION

10.1 Automatic Termination. If during the Term all or any part of the Premises
is permanently taken for any public or quasi-public use under any statute or by
right of eminent domain, or purchased under threat of such taking, this Lease
shall automatically terminate on the date on which the condemning authority
takes possession of the Premises.

10.2 Optional Termination. If during the term any part of the Project is taken
or purchased by right of eminent domain or in lieu of condemnation, whether or
not the Premises are directly affected, then if in the reasonable opinion of
Landlord substantial alteration or reconstruction of the Project is necessary or
desirable as a result thereof, or the amount of parking available to the Project
is materially and adversely affected, Landlord shall have the right to terminate
this Lease by giving Tenant at least thirty days written notice of such
termination.

10.3 Award. Landlord shall be entitled to receive and retain the entire award
or consideration for the affected lands and improvements and Tenant shall not
have or advance any claims against Landlord for the value of its property or
its leasehold estate or the unexpired term of this Lease or for costs of
removal or relocation or business interruption expense or any other damages
arising out of the taking or purchase. Nothing herein shall give Landlord any
interest in or preclude Tenant from seeking and recovering on its own account
from the condemning authority any award of compensation attributable to the
taking or purchase of Tenant's chattels or trade fixtures or attributable to
Tenant's relocation expenses provided that any such separate claim by Tenant
shall not reduce or adversely affect the amount of Landlord's award. If any
such award made or compensation paid to Tenant specifically includes an award
or amount for Landlord, Tenant shall promptly account therefor to Landlord.

ARTICLE 11 MAINTENANCE

11.1 By Tenant. Tenant shall maintain equipment, alterations or other
improvements whether constructed for Tenant's initial occupancy or made
subsequently pursuant to Article 15, such as supplemental or special cooling
systems not consistent with building standard tenant improvements as established
by the Landlord. If Tenant does not comply with its obligations under this
Article, Landlord may, but need not, make such repairs and replacements or
obtain such service contracts, and Tenant shall pay Landlord the cost thereof
upon demand. Tenant also shall make such repairs and alterations necessary to
comply with the requirements of any governmental or quasi-governmental
authority' having jurisdiction

11.2 By Landlord. Landlord shall maintain the Premises and the improvements
thereon (including all doors, plate glass, and heating, air conditioning,
ventilation, electrical and plumbing systems serving the Premises), in good
condition and repair. Landlord shall provide janitorial services to the Premises
five nights per week. Landlord shall maintain the Project and all Common Areas
in good condition and repair in accordance with standards then prevailing for
comparable properties of like age and character. Landlord shall repair
structural defects in roof or walls and any common utility facilities in the
Common Areas. Landlord shall not be liable or responsible for breakdowns or
temporary interruptions in access or utilities nor for interference with
Tenant's business or Tenant's access to the Premises during the course of
repairs or remedial work.

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<PAGE>

ARTICLE 12 UTILITIES

Landlord shall supply the following services to assure Tenant's operations in
the Premises 24 hours/day, 365 days/year:

A.   Electrical. Landlord shall provide 800 amps of 480 volt three phase
     electrical power for Tenant's suite (#500) Said power will brought into one
     of the Project's electrical rooms, as shown on Exhibit "E", and it is
     Tenant's responsibility and cost to distribute said power from the
     electrical room to and throughout their suite. Tenant shall obtain its
     electricity directly from Landlord, which shall be separately metered by a
     meter installed by Landlord at its cost, with no mark up.

B.   Heat and air conditioning: SEE ARTICLE 27(D)

C.   Hot and cold water from the regular building outlets for lavatory and
     restrooms and for drinking purposes.

D.   Passenger elevator service in common with other tenants to be provided by
     automatic elevators. Landlord shall have the right to restrict to use of
     elevators for freight purposes to the freight elevator and to hours to be
     reasonably determined by Landlord so long as elevator is reasonably
     available (24 hours/day, 7 days/week), without charge, for Tenant's
     construction purposes. Landlord shall have the right to limit the number of
     elevators to be in operation on Saturdays, Sundays and holidays.

E.   Maintenance in good order, condition and repair of the parking facilities
     and all driveways leading thereto. Landlord shall keep and maintain the
     landscaped area and parking facilities in a neat and orderly condition.
     Landlord reserves the right to designate areas, in a non-discriminatory
     manner, of the appurtenant parking facilities where Tenant, its agents,
     employees and invitees shall park and may exclude Tenant and its agents,
     employees and invitees from parking in other areas as designated by
     Landlord; provided, however, Landlord shall not be liable to Tenant for the
     failure of any tenant or its invitees, employees and invitees from parking
     in other areas as designated by Landlord, provided, however, Landlord shall
     not be liable to Tenant for the failure of any tenant or its invitees,
     employees, agents or customers to abide by Landlord's designations or
     restrictions. Tenant is aware that Landlord may be required to designate
     certain parking stalls due to governmental request or order to accommodate
     car or van poolers.

Landlord acknowledges that Tenant's operations require 24-hour/day, 7/days/week
operation. As a consequence thereof, Landlord shall give to Tenant reasonable
advance notice of any planned shut downs of any Building system for scheduled
routine maintenance and/or of repairs, alterations, additions or improvements in
or to the Building Landlord shall make every effort to minimize inconvenience to
Tenant by rescheduling the times for the performance of such work upon
reasonable request of Tenant, provided that any increase in costs incurred by
Landlord as a result of such rescheduling shall be paid for by Tenant within
thirty (30) days after Tenant's receipt of Landlord's written statement and
supporting documentation.

ARTICLE 13 LANDLORD RIGHT OF ENTRY

Upon reasonable notice to Tenant, Landlord shall have access to the Premises for
purposes of showing the Premises to current or prospective lenders, to
prospective purchasers of the Project, and, during the twelve-month period
preceding the expiration of the term of this Lease, to prospective tenants
Landlord shall at all times have access to the Premises for purposes of
inspection and performing Landlord's obligations and exercising its rights under
this Lease.

ARTICLE 14 SIGNS

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Tenant shall not place or permit to be placed any sign, picture, advertisement,
notice, lettering or decoration on any part of the outside of the Premises or
anywhere in the interior of the Premises which is visible from the outside of
the Premises without Landlord's prior written approval. All of Tenant's signs
shall be subject to Landlord's prior approval.

ARTICLE 15 TENANT ALTERATIONS

15.1 Tenant Alterations. Tenant may from time to time at its own expense make
changes, additions and improvements in the Premises, provided that any such
change, addition or improvement shall:

      (a) comply with the requirements of any governmental or quasi-governmental
authority having jurisdiction (including, without limitation, the Americans with
Disabilities Act), with the requirements of Landlord's insurance carriers, and
with Landlord's safety and access requirements, including restrictions on
flammable materials and elevator usage;

      (b) not be commenced until Landlord has received satisfactory evidence
that all required permits have been obtained;

      (c) be made only with the prior written consent of Landlord (which may be
withheld in Landlord's sole discretion, to the extent it relates in Landlord's
opinion to the structure or electrical, HVAC, plumbing or sprinkler systems of
the Building, but which otherwise shall not be unreasonably withheld);

      (d) be constructed in good workmanlike manner and conform to complete
working drawings prepared by a licensed architect and submitted to and approved
by Landlord;

      (e) be of a quality that equals or exceeds the then current standard for
the Project and comply with all building, fire and safety codes;

      (f) be carried out only during hours approved by Landlord by licensed
contractors selected by Tenant and approved in writing by Landlord, who shall
deliver to Landlord before commencement of the work performance and payment
bonds as well as proof of workers' compensation and general liability insurance
coverage, including coverage for completed operations and contractual liability,
with Landlord and its agents and designees named as additional insureds, in
amounts, with companies, and in form reasonably satisfactory to Landlord, which
shall remain in effect during the entire period in which the work shall be
carried out. Notwithstanding the foregoing, only subcontractors selected or
designated by Landlord may be used to make connection with the Project's main
electrical, plumbing or HVAC systems, except connections to circuit panels,
pipes or ducts within the Premises; and

      (g) upon completion, be shown on accurate "as built" reproducible drawings
in the form of reverse sepia transparencies or mylars delivered to Landlord.

15.2 Tenant Installations. Tenant may install in the Premises its usual trade
fixtures and personal property in a proper manner, provided that no installation
shall interfere with or damage the mechanical or electrical systems or the
structure of the Building. Landlord may require that any work that may affect
structural elements or mechanical, electrical, heating, air conditioning,
plumbing or other systems be performed by Landlord at Tenant's cost or by a
contractor designated by Landlord.

15.3 Mechanics Liens. Tenant shall pay before delinquency all costs for work
done or caused to be done by Tenant in the Premises which could result in any
lien or encumbrance on Landlord's interest in the Project or any part thereof,
shall keep the title to the Project and every part thereof free and clear of any
lien or encumbrance in respect of such work, and shall indemnify and hold
harmless Landlord and Landlord's agents and employees against any claim, loss,
cost, demand or legal or other expense, whether in respect of any lien or
otherwise, arising out of the supply of material, services or labor for such
work. Tenant shall immediately notify Landlord of any such lien, claim of lien
or other action of which it has or reasonably should have knowledge and that
affects the title to the Project or any part thereof, and shall cause the same
to be removed by bonding or otherwise within five days, failing which Landlord
may take such action as Landlord deems necessary to remove same and the entire
cost thereof shall be immediately due and payable by Tenant to Landlord. If
provided by applicable law, Tenant shall cause such postings to be made and
notices given as shall prevent any mechanics' lien for work done for Tenant from
attaching to the Project.

ARTICLE 16 ASSIGNMENT AND SUBLETTING

16.1 Consent Required. Tenant shall not assign its interest under this Lease or
sublet all or any part of the Premises without Landlord's prior written consent,
which shall not be unreasonably withheld. Tenant shall not at any time pledge,
hypothecate, mortgage or otherwise encumber its interest under this Lease as
security for the payment of a debt or the performance of a contract.

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<PAGE>

Tenant shall not permit its interest under this Lease to be transferred by
operation of law. Any purported assignment or sublease made without Landlord's
consent shall be void.

16.2 Requests for Approval. Landlord shall be under no obligation to decide
whether consent will be given or withheld unless Tenant has first provided to
Landlord: (a) the name and legal composition of the proposed assignee or
subtenant and the nature of its business: (b) the use to which the proposed
assignee or subtenant intends to put the Premises; (c) the terms and conditions
of the proposed assignment or sublease and of any related transaction between
Tenant and the proposed assignee or subtenant; (d) information related to the
experience, integrity and financial resources of the proposed assignee or
subtenant; (e) such information as Landlord may request to supplement, explain
or provide details of the matters submitted by Tenant pursuant to subparagraphs
(a) through (d); and (f) reimbursement for all costs incurred by Landlord,
including attorneys' fees, in connection with evaluating the request and
preparing any related documentation.

16.3 Continued Responsibility. Tenant shall remain fully liable for performance
of this Lease, notwithstanding any assignment or sublease, for the entire Lease
Term.

16.4 Excess Proceeds. If consent to an assignment or sublease is given, Tenant
shall pay to Landlord, as additional rent, all amounts received from the
assignee or subtenant in excess of the amounts otherwise payable by Tenant to
Landlord with respect to the space involved, measured on a per square foot
basis.

16.5 Limitations. Without limiting appropriate grounds for withholding consent,
it shall not be unreasonable for Landlord to withhold consent if the proposed
assignee or subtenant is a tenant in another building owned by Landlord or by an
affiliate of Landlord or of any of Landlord's constituent partners or principals
or if the use by the proposed assignee or subtenant would contravene this Lease
or any restrictive use covenant or exclusive rights granted by Landlord or if
the proposed assignee or subtenant does not intend to occupy the Premises for
its own use or if the nature of the proposed assignee or subtenant is not
compatible with the Project.

16.6 No Waiver. No consent shall constitute consent to any further assignment or
subletting.

16.7 Transfer by Landlord. Upon a sale or other transfer of the Project (or a
portion thereof containing the Premises) by Landlord, Landlord's interest in
this Lease shall automatically be transferred to the transferee, the transferee
shall automatically assume all of Landlord's obligations under this Lease
accruing from and after the date of transfer, and the transferor shall be
released of all obligations under this Lease arising after the transfer. Tenant
shall upon request attorn in writing to the transferee.

ARTICLE 17 SUBORDINATION AND ATTORNMENT

17.1 Subordination. This Lease is and shall be subject and subordinate in all
respects to all existing and future mortgages or deeds of trust now or hereafter
encumbering the Project or any part hereof. The holder of any mortgage or deed
of trust may elect to be subordinate to this Lease.

17.2 Lender Protection. Upon a transfer in connection with foreclosure or
trustee's sale proceedings or in connection with a default under an encumbrance,
whether by deed to the holder of the encumbrance in lieu of foreclosure or
otherwise, Tenant, if requested, shall in writing attorn to the transferee, but
the transferee shall not be:

      1     subject to any offsets or defenses which Tenant might have against
            Landlord; or

      2     bound by any prepayment by Tenant of more than one month's
            installment of rent;

      3     or subject to any liability or obligation of Landlord except those
            arising after the transfer.

17.3 Documentation. The subordination provisions of this Article shall be
self-operating and no further instrument shall be necessary. Nevertheless
Tenant, on request, shall execute and deliver any and all instruments further
evidencing such subordination.

17.4 Other Transactions. Landlord may' at any time and from time to time grant,
receive, dedicate, relocate, modify, surrender or otherwise deal with easements,
rights of way, restrictions, covenants, equitable servitudes or other matters
affecting the Project without notice to or consent by Tenant.

ARTICLE 18 ESTOPPEL CERTIFICATES

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Tenant shall at any time within ten days after written request from Landlord
execute, acknowledge and deliver to Landlord a statement in writing: (a)
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 date to which the
rent and other charges are paid in advance, if any; (b) confirming the
commencement and expiration dates of the term; (c) confirming the amount of the
security deposit held by Landlord; (d) acknowledging that there are not, to
Tenant's knowledge, any uncured defaults on the part of Landlord hereunder, or
specifying such defaults if any are claimed; and (e) confirming such other
matters as to which Landlord may reasonably request confirmation. Any such
statement may be conclusively relied upon by a prospective purchaser or
encumbrancer of the Premises or the Project. If Landlord desires to finance or
refinance the Project, Tenant hereby agrees to deliver to any lender designated
by Landlord such financial statements of Tenant as may be reasonably required by
such lender. Such statement shall include the past three years' financial
statements of Tenant. All such financial statements shall be received by
Landlord in confidence and shall be used only for the purposes herein set forth.

ARTICLE 19 QUIET ENJOYMENT

If Tenant pays the rent and observes and performs the terms, covenants and
conditions contained in this Lease, Tenant shall peaceably and quietly hold and
enjoy the Premises for the Term without hindrance or interruption by Landlord,
or any other person lawfully claiming by, through or under Landlord unless
otherwise permitted by the terms of this Lease. Tenant acknowledges that the
exercise by the Landlord of any of the rights conferred on Landlord under this
Lease and the entry upon the Premises for or in connection with such purposes
shall not be deemed to be a constructive or actual eviction of the Tenant and
shall not be considered to be a breach of Landlord's covenant of quiet
enjoyment.

ARTICLE 20 SURRENDER AND HOLDOVER

20.1 Surrender. Upon the expiration or termination of this Lease or of Tenant's
right to possession. Tenant shall surrender the Premises in a clean undamaged
condition and shall remove all of Tenant's equipment, fixtures and property and
repair all damage caused by the removal. Such removal shall include, without
limitation, the removal of all telephone wire located within the Premises and
from the Premises to the central telephone box for the Building. Tenant shall
not remove permanent improvements that were provided by Landlord at the
commencement of this Lease and shall not remove permanent improvements later
installed by Tenant unless directed to do so by Landlord.

20.2 Holdover. If Tenant holds over without Landlord's consent, Tenant shall, at
Landlord's election, be a tenant at will or a tenant from month-to-month. In
either case rent shall be payable monthly in advance at a rate equal to one and
one-half (150%) times the rate in effect immediately before the holdover began.
A holdover month-to-month tenancy may be terminated by either party as of the
first day of a calendar month upon at least ten days' prior notice. A holdover
tenancy at will is terminable at any time by either party without notice,
regardless of whether rent has been paid in advance. Upon a termination under
this Section, unearned rent shall be refunded following the surrender of
possession provided Tenant is not otherwise in breach of this Lease.

ARTICLE 21 BREACH. DEFAULT. AND REMEDIES

21.1 Default. The following shall constitute "Events of Default":

      (a) Tenant's failure to pay rent or any other amount due under this Lease
within five days after notice of nonpayment; or

      (b) Tenant's failure to execute, acknowledge and return a subordination
agreement under Article 17 or an estoppel certificate under Article 18 within
ten days after request; or

      (c) Tenant's failure to perform any other obligation under this Lease
within fifteen days after notice of nonperformance; provided, however, that if
the breach is of such a nature that it cannot be cured within fifteen days, no
Event of Default shall be deemed to have occurred by reason of the breach if
cure is commenced promptly and diligently pursued to completion within a period
not longer than ninety days; and provided further, that in the event of a breach
involving an imminent threat to health or safety, Landlord may in its notice of
breach reduce the period for cure to such shorter period as may be reasonable
under the circumstances; or

      (d) Tenant vacates, abandons, or otherwise ceases to use the Premises on a
substantial continuing basis except temporary absence excused by reason of fire,
casualty, failure of services or other cause wholly beyond Tenant's control; for
these purposes, absence for five consecutive business days shall conclusively be
deemed an abandonment.

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<PAGE>

21.2 Remedies. Upon the occurrence of an Event of Default, Landlord, at any time
thereafter without further notice or demand may exercise any one or more of the
following remedies concurrently or in succession:

      (a) Terminate Tenant's right to possession of the Premises by legal
process or otherwise, with or without terminating this Lease, and retake
exclusive possession of the Premises.

      (b) From time to time relet all or portions of the Premises, using
reasonable efforts to mitigate Landlord's damages. In connection with any
reletting, Landlord may relet for a period extending beyond the term of this
Lease and may make alterations or improvements to the Premises without releasing
Tenant of any liability. Upon a reletting of all or substantially all of the
Premises, Landlord shall be entitled to recover all of its then prospective
damages for the balance of the Lease Term measured by the difference between
amounts payable under this Lease and the anticipated net proceeds of reletting.

      (c) From time to time recover accrued and unpaid rent and damages arising
from Tenant's breach of the Lease, regardless of whether the Lease has been
terminated, together with applicable late charges and interest at the rate of
18% per annum or the highest lawful rate, whichever is less.

      (d) Enforce the statutory Landlord's lien on Tenant's property.

      (f) Recover all costs, expenses and attorneys' fees incurred by Landlord
in connection with enforcing this Lease, recovering possession. reletting the
Premises or collecting amounts owed, including, without limitation, costs of
alterations, brokerage commissions, and other costs incurred in connection with
any reletting.

      (g) Perform the obligation on Tenant's behalf and recover from Tenant,
upon demand, the entire amount expended by Landlord plus 20% for special
handling, supervision, and overhead.

      (h) Pursue other remedies available at law or in equity.

21.3 Subtenancies. Upon a termination of Tenant's right to possession, whether
or not this Lease is terminated: (a) subtenancies and other rights of persons
claiming under or through Tenant shall be terminated or (b) Tenant's interest in
such subleases or other arrangements shall be assigned to Landlord. Landlord may
separately elect termination or assignment with respect to each such subtenancy
or other matter.

ARTICLE 22 LANDLORD LIABILITY

Notwithstanding anything to the contrary in this Lease, neither Landlord nor
Landlord's directors, officers, shareholders, employees, agents, constituent
partners, beneficiaries, trustees, representatives, successors or assigns
(collectively, "Landlord's Affiliates") shall be personally responsible or
liable for any representation, warranty, covenant, undertaking or agreement
contained in the Lease, and the sole right and remedy of the Tenant or any
subsequent sublessee or assignee shall be against Landlord's interest in the
Project. Neither Tenant nor any subsequent sublessor or assignee shall seek to
obtain any judgment imposing personal liability against Landlord, Landlord's
Affiliates, or their successors or assigns nor execute upon any judgment or
place any lien against any property other than Landlord's interest in the
Project.

ARTICLE 23 NOTICES

Any notice from one party to the other shall be in writing and shall be deemed
duly served: (a) if delivered personally to a responsible employee of Tenant, if
sent by facsimile with receipt acknowledged, or if mailed by registered or
certified mail addressed to Tenant at the Premises or (b) if mailed by
registered or certified mail to Landlord at the address set forth in Section 1.
15 or such other address as Landlord may designate. Any notice to Tenant prior
to Tenant's taking possession of the Premises, however, shall instead be sent to
the address set forth in Section 1.14. Any notice shall be deemed to have been
given when mailed, if mailed, when faxed, if faxed, and when delivered, if
personally delivered.

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ARTICLE 24 BROKERAGE

Tenant warrants and represents that no broker or other person is entitled to
claim a commission, broker's fee or other compensation in connection with this
Lease except: (i) brokers or other persons that Landlord may have retained or
employed directly, and (ii) brokers whom Tenant has previously specifically
designated in writing to Landlord as Tenant's representative as listed in
Section 1.16. Tenant shall defend, indemnify and hold Landlord harmless from all
claims or liabilities arising from any breach of the foregoing representation
and warranty.

ARTICLE 25 RELOCATION

      INTENTIONALLY DELETED

ARTICLE 26 GENERAL

26.1 Severability. If any term, covenant or condition of this Lease, or the
application thereof, is to any extent held or rendered invalid, it shall be and
is hereby deemed to be independent of the remainder of the Lease and to be
severable and divisible therefrom, and its invalidity, unenforceability or
illegality shall not affect, impair or invalidate the remainder of the Lease or
any part thereof.

26.2 No Waiver, The waiver by Landlord of any breach of any term, covenant or
condition contained in this Lease shall not be deemed to be a waiver of such
term, covenant or condition or of any subsequent breach of the same or of any
other term, covenant or condition contained in this Lease. The subsequent
acceptance of rent by Landlord shall not be deemed to be a waiver of any
preceding breach by Tenant of any term, covenant or condition of this Lease,
regardless of Landlord's knowledge of such preceding breach at the time of
acceptance of rent. No term, covenant or condition of this Lease shall be deemed
to have been waived by Landlord unless such waiver is in writing by Landlord.

26.3 Effect of Payment. No payment by Tenant or receipt by Landlord of a lesser
amount than the monthly payment of rent herein stipulated is deemed to be other
than on account of the earliest stipulated rent, nor is any endorsement or
statement on any check or any letter accompanying any check or payment of rent
deemed an acknowledgment of full payment or accord and satisfaction, and
Landlord may accept and cash any check or payment without prejudice to
Landlord's right to recover the balance of the rent due and pursue any other
remedy provided in this Lease.

      26.4 Delay. If either party is delayed or hindered in or prevented from
      the performance of any term, covenant or act required hereunder by reasons
      of strikes, labor troubles, inability to procure materials or services,
      power failure, restrictive governmental laws or regulations, riots,
      insurrection, sabotage, rebellion, war, act of God, or other reason
      whether of a like nature or not that is beyond the control of the party
      affected, financial inability excepted, then the performance of that term,
      covenant or act is excused for the period of the delay and the party
      delayed shall be entitled to perform such term, covenant or act within the
      appropriate time period after the expiration of the period of such delay.
      Nothing in this Section, however, shall excuse Tenant from the prompt
      payment of any amount payable under this Lease nor from the consequences
      of Tenant Delay as provided in Exhibit C (if attached).

      26.5 Lender Notice, In the event of a material default by Landlord of a
      sufficiently serious nature that Tenant considers the utility of the
      Premises to Tenant to be significantly impaired, Tenant shall give written
      notice of the default to Landlord and shall simultaneously send a copy of
      the notice to the holder of any encumbrance, the name and address of whom
      has previously been furnished in writing to Tenant. If Landlord fails to
      cure the default within a reasonable time, Tenant shall send a second
      notice to that effect to the holder of the encumbrance, with a copy to
      Landlord, and the holder of the encumbrance then shall have a reasonable
      time, not less than thirty days, to cause the default to be remedied.

      26.6 No Offer. The submission of this Lease for examination does not
      constitute a reservation of an option to lease the Premises, and this
      Lease becomes effective as a lease only upon its execution and delivery by
      Landlord and Tenant.

      26.7 Successors. All rights and liabilities under this Lease extend to and
      bind the successors and assigns of Landlord and permitted successors and
      assigns of Tenant. No rights, however, shall inure to the benefit of any
      transferee of the Tenant unless the transfer has been consented to by the
      Landlord in writing as provided in Section 16.1. If there is more than one
      Tenant, they are all bound jointly and severally by the terms, covenants
      and conditions of this Lease.

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<PAGE>

26.8 Integration. This Lease and the Exhibits hereto attached, set forth all the
covenants, promises, agreements, conditions and understandings between Landlord
and Tenant concerning the Premises and there are no other covenants, promises,
agreements, conditions or understandings, either oral or written, between them.
No alteration, amendment or addition to this Lease shall be binding upon
Landlord or Tenant unless in writing and signed by Tenant and Landlord.

26.9 WAIVER OF JURY TRIAL. IN ANY LITIGATION BETWEEN LANDLORD AND TENANT, THE
MATTER SHALL BE DECIDED BY A JUDGE SITTING WITHOUT A JURY, AND TENANT
ACCORDINGLY WAIVES ITS RIGHT TO A JURY TRIAL.

26.10 Governing Law. This Lease shall be construed in accordance with and
governed by the laws of the State of Arizona.

26.11 Deadlines Enforceable. Time is of the essence of this Lease and of every
part hereof

26.12 Counterparts. This Lease may be executed in counterparts, which together
shall constitute a single instrument.

26.13 Additional Provisions:

      1. Tenant's Option to Renew

            (A)   Provided that this Lease is then in full force and effect and
                  Tenant is not in default, on the date of exercise of this
                  Option, hereunder after notice and the expiration of any
                  applicable grace period, Tenant shall have the option to
                  extend the Term for two (2) additional periods of five (5)
                  years each (the "Extension Term(s)"). The Extension Term(s)
                  shall commence on the day after the initial Lease term and the
                  prior Extension Term (if any) expires ("Expiration Date(s)")
                  and shall expire on the fifth (5th) anniversary of the
                  Expiration Date(s) unless the Extension Term(s) shall sooner
                  end pursuant to this Lease.

            (B)   The terms and conditions shall be identical to those in the
                  primary lease except for the rental rate, which shall be the
                  market rental rate determined by Landlord and Tenant based on
                  the rental rate allowances and concessions for comparable
                  buildings in the same immediate geographic area. Landlord
                  shall provide Tenant a proposed rental rate at least nine (9)
                  months but not more than twelve (12) months prior to the
                  termination of the Lease term. Tenant will accept/reject such
                  offer no less than six (6) months prior to the termination of
                  the Lease. If Landlord and Tenant are unable to agree on a
                  market rental rate, allowances and concessions, each shall
                  hire a licensed commercial real estate broker with at least
                  ten (10) years of experience in the local commercial real
                  estate market and those brokers will hire a third licensed
                  commercial real estate broker with the same experience in the
                  local commercial real estate market to all determine a market
                  rate, allowances and concessions. The average rate, allowances
                  and concessions determined by these three (3) brokers will be
                  considered the market rental rate and improvement allowance
                  for the purposes of the Renewal Option.

            (C)   Promptly after the rent has been determined, Landlord and
                  Tenant shall execute, acknowledge and deliver an agreement
                  setting forth the rent for the Extension Term(s). as finally
                  determined, provided that the failure of the parties to do so
                  shall not affect their respective rights and obligations under
                  the Lease.

Nowithstanding any provisions in Sections 1-26 of the Lease, Landlord and Tenant
hereby agree as follows:

                                       15
<PAGE>

27.   Services.

      A.    Landlord's Obligations. Landlord shall use all reasonable efforts to
            furnish to Tenant (I) water at those points of supply provided for
            general use of tenants of the Building in the common areas thereof;
            (2) heated and refrigerated air conditioning ("HVAC") as appropriate
            to the common areas of the Building, at such temperatures and in
            such amounts as are standard for comparable buildings in the
            vicinity of the Building; (3) janitorial service to the common areas
            of the Building on weekdays, other than holidays, for
            Building-standard installations and such window washing as may from
            time to time be reasonably required; and (4) elevator(s) for ingress
            and egress to the floor on which the Premises are located, in common
            with other tenants, provided that Landlord may reasonably limit the
            number of operating elevators during non-business hours and
            holidays. Landlord shall maintain the common areas of the Building
            in reasonably good order and condition.

      B.    Electrical Service. All electrical power for the Premises and for
            the operation of Tenant's equipment shall be submetered by Landlord,
            and be furnished, installed and maintained at Tenant's sole expense.
            Without limiting the generality of the foregoing, Tenant, at its
            sole cost and expense, shall pay the cost of all equipment, meters,
            switches, transformers, feeders, risers, and wiring required to
            provide electrical service to the Premises. The installation of all
            electrical equipment shall be done only in substantial accordance
            with plans and specifications that have been previously submitted to
            and approved by Landlord in writing. Whenever Tenant is required to
            pay' the cost of any electrical equipment under the foregoing
            provisions, the cost thereof shall include the cost of installation,
            operation, use and maintenance of such electrical equipment. If
            electrical service to the Premises is submetered, the submeter shall
            be read by Landlord and Tenant shall pay to Landlord, within ten
            (10) days after Tenant's receipt of an invoice therefore the actual
            cost of such electrical service based on rates charged for such
            service by the utility company furnishing such service, including
            all fuel adjustment charges, demand charges and taxes.

      C.    Restoration of Services/Tenant Self-Help Remedy. Landlord shall use
            good faith best efforts to restore any service described in Section
            27(a) that becomes unavailable interrupted, discontinued or
            insufficient; however, such unavailability shall not render Landlord
            liable for any damages caused thereby, be a constructive eviction of
            Tenant, constitute a breach of any implied warranty, or, except as
            provided in the next sentence, entitle Tenant to any abatement of
            Tenant's obligations hereunder. If, however, Tenant is prevented
            from using the Premises for more than 4 consecutive business days
            because of the unavailability of any such service, then Tenant
            shall, as its exclusive remedy be entitled to a reasonable abatement
            of Rent for each consecutive day that Tenant is so prevented from
            using the Premises. Tenant Self-Help Remedy: if the Landlord shall
            fail to restore said service within five (5) days of its
            interruption, then Tenant may make perform such obligation and
            offset the amount of the reasonable cost of such performance against
            any base rent, additional rent or any other amounts payable be
            Tenant under this Lease.

D. Generator & HVAC Access. Landlord will install its own generator system,
Tenant shall be granted the right to purchase up to 500 KW of power from the
Building's generator based on the initial fee and monthly charges specified
below. Tenant shall have the right to install a minimum of 2-4" conduits to
connect the Premises to the generator power connection point. Tenant shall have
the right to utilize up to 60 tons of capacity from the Building's chilled water
system based on the monthly charges specified below. Landlord shall "stub" the
chilled water lines to a mutually determined location. Landlord shall provide
chilled water at approximately 55 degrees fahrenheit, and such chilled water
shall be provided 24 hours a day/7 days a week/365 days a year throughout the
Term of the Lease. Landlord shall use all possible efforts to ensure that the
chilled water is provided to Tenant continuously, and at the correct
temperature. Tenant shall have the right to review the maintenance procedures of
the generator and chilled water system and shall have the periodic right to
review such records.

      Generator/HVAC Fees:
<PAGE>

            Initial charge: $175,000.00

            Monthly access: $1,500.00

            Monthly fuel service: Proportionate share of actual fuel costs

      THE FOLLOWING SECTIONS (28-35) ALL REQUIRE AND ARE SUBJECT TO LANDLORD'S
      PRIOR WRITTEN APPROVAL. SAID APPROVAL WILL NOT BE UNREASONABLY WITHHELD,
      CONDITIONED, OR DELAYED.

      28.   Risers & Conduit Access Landlord shall provide Tenant with rights to
            install four (4) four-inch (4") conduits ("Main Conduit") which
            shall run from the Basement to the Premises and which shall run the
            entire length of the building to connect Tenant's telecommunications
            facility to other tenants in the building and to connect to the
            point of entry or "hand off point/meet me room" in the building for
            all fiber carriers. Tenant shall also have the right to run feeder
            conduit stemming from the Main Conduit to connect each tenant on
            each floor of the building. All conduit will be installed at
            Tenant's sole cost and Landlord shall not charge any fees for said
            conduit access.

      29.   Battery Installation Tenant shall have the right to install wet cell
            batteries with the necessary seismic racks and spill containment.

      30.   Grounding Riser Tenant, at no additional rental cost, shall have the
            right to install a separate electrical ground and/or tie into the
            Building's primary ground system in accordance with equipment
            requirements and applicable laws.

      31. Antennae

            (a)   Tenant shall have the right to install a GPS antenna in a
                  location to be mutually agreed upon by both Landlord and
                  Tenant. Tenant shall be granted sufficient conduit space for
                  such installation and not be charged for such conduit or roof
                  space.

            (b)   Tenant shall be granted access to the roof 24 hours per day
                  via escort by a Building engineer or security guard. During
                  normal business hours, Landlord shall make arrangements for
                  immediate access and after normal business hours and on
                  weekends, Landlord shall provide a telephone number for Tenant
                  to contact to arrange immediate access.

32.   Fire Protection & Life Safety. Tenant shall have the right to convert any
      existing sprinkler system or install a preaction or FM 200 system. Tenant
      shall install such system subject to local codes and ordinances.

33.   Hazardous Substances To the best of Landlord's knowledge, no part of the
      Premises or the Building including without limitation, the walls,
      ceilings, structural steel, flooring, pipes or boilers, is wrapped,
<PAGE>

      insulated, fireproofed or surfaced with any asbestos-containing materials.
      Landlord shall provide the Premises and all other areas of the Premises
      where Tenant places equipment free of hazardous materials.

34.   Express Waiver of Landlord's Lien. Landlord hereby expressly waives its
      Landlord's lien and any and all rights granted by or under any present or
      future laws to levy or distrain for rent, in arrears, in advance, or both,
      upon any or all personalty, including, but not limited to [supporting
      towers, antennas, satellite dish(es), Connecting Equipment] equipment,
      trade fixtures, furniture and other personal property of Tenant or any
      assignee or subtenant of Tenant in the Premises.

35.   Allowable Use of Certain Hazardous Materials. Tenant may use and store the
      following materials in the ordinary course of its business: fuel for the
      generator(s) in order to supply an uninterrupted power source (UPS); acid
      contained within batteries for back-up power; reasonable amounts of
      standard cleaning fluid and materials customarily used in conjunction with
      business machines; cleaning supplies in reasonable quantities; coolant for
      any Tenant installed HVAC system, or other materials used in fire
      suppression and any other materials deemed necessary to Tenant's business.
      Landlord may use, but not store, on the Premises the following materials
      in the ordinary course of business: cleaning supplies, insecticides,
      fungicides, and rodenticides. Tenant shall not indemnify Landlord for
      releases of any hazardous materials that exist on the Premises at the time
      of execution of this Lease or are brought on the Premises, into the
      building, or on, in or under the land upon which the Building is located
      by anyone other than Tenant, its employees, agents, or third-party
      contractors. This provision shall survive the expiration or sooner
      termination of this Lease.

                                  TENANT:  Advanced Telecommunications Inc.
                                           A Delaware corp.

                                      By: _________________________________

                                      Its: ________________________________

                                      Date _____________________________________

                                  LANDLORD:

                                      SOFI-IV SIM OFFICE INVESTORS II, LP, an
                                      Delaware limited partnership

                                      By:   Scottsdale Property Management 97,
                                            L.L.C., an Arizona limited liability
                                            company, Agent

                                            By _________________________________
                                               Authorized signatory

                                      Date______________________________________
<PAGE>

                                    EXHIBIT A

                                  THE PREMISES

                                       A-1
<PAGE>

                                   EXHIBIT A-1

                                   FLOOR PLAN

                                       A-2
<PAGE>

                                    EXHIBIT B

                             CONSTRUCTION PROVISIONS

1 Preliminary Space Plan. Attached to this Lease as Exhibit A is a preliminary
space plan approved by Landlord and Tenant showing the size, nature and location
of the improvements to be constructed in the Premises (the "Improvements").
Promptly following execution of this Lease, Tenant shall meet with Landlord's
architect and shall provide such information and make such selections as may be
necessary for the expeditious completion of the planning process.

2 Working Drawings. Based upon the preliminary space plan and the information
provided and selections made by Tenant, Landlord shall cause working drawings
and specifications (collectively, the "Plans") to be prepared for the
Improvements. The Plans shall be subject to Tenant's reasonable approval. Tenant
shall respond with all of its specific objections or comments to the proposed
Plans within five days after receipt, and the Plans shall be modified to satisfy
any reasonable objection of Tenant. Tenant shall promptly give its written
approval of the revised Plans or indicate specific changes required to be made.
Any revisions of the Plans after the revisions to the initial draft of the
proposed Plans shall be made at Tenant's sole expense, payable on demand.

3 Cooperation, During the entire course of the process described above, both
Landlord and Tenant shall review and respond to submissions by the other party
with reasonable dispatch. Tenant shall respond with its approval or comments
within five days after receipt of initial drawings, specifications, or other
materials requiring Tenant's review and within three days after receipt of
revised versions of such documents or materials. From time to time at the
request of either party Landlord and Tenant shall devise, and revise as
necessary, working schedules for the preparation of the Plans and the
construction of the Improvements. Tenant shall not permit any supplier,
installer, contractor, or other person employed by Tenant to interfere in any
way with the progress of the work. Access by Tenant's suppliers, contractors and
installers shall be subject to (i) scheduling by Landlord upon at least ten
days' prior notice by Tenant, and (ii) compliance with all requirements imposed
by Landlord with respect to insurance, cooperation, permits, licenses, bonding,
hours of work, safety and use of flammable substances.

4 Redesign Option. If after the Plans are completed and Landlord's contractor
has submitted a price for the work, the estimated costs of construction exceed
the Tenant Improvement Allowance, Tenant may elect within three days after
receipt of the cost estimate to attempt to reduce the associated cost by
reducing the scope of the work to be done. The changes, which shall be subject
to Landlord's prior approval, shall be incorporated in revised Plans. Any
redesign and rebidding shall be completed within seven days after receipt of the
initial cost estimate.

5 Cost. Prior to commencement of construction, Tenant shall pay to Landlord the
amount, if any, by which the estimated costs of construction exceed the Tenant
Improvement Allowance as set forth in Section 1.13. Any difference between
actual and estimated costs shall be paid or refunded, as the case may be, within
ten days after receipt of Landlord's statement calculating the amount due.
Landlord shall prepare and deliver the statement within a reasonable time after
completion of punchlist items. "Costs of construction" of the Improvements as
used in this Article means all costs and expenses incurred to design and build
the improvements, including, without limitation, permit and inspection fees,
management and supervision fees, taxes, amounts paid to contractors,
subcontractors, and suppliers, architects' fees, engineering costs, premiums for
bonds and insurance, utilities, equipment rental, demolition, labor, materials,
and supplies.

6 Punchlist. Within ten days after taking possession of the Premises, Tenant
shall deliver to Landlord a written punchlist specifying all defects in
materials or workmanship in the Improvements. Any defects not specified in the
punchlist, except latent defects not readily discoverable by inspection, are
waived. Landlord shall promptly cause all matters appearing on the punchlist to
be corrected.

7 Delay. If completion of construction of improvements within the Premises or
delivery of possession of the Premises is delayed by Tenant Delay, then the
Commencement Date shall be deemed to have occurred and rent shall begin to
accrue as of the date when they would have done so but for the Tenant Delay.
"Tenant Delay" means delay as a result of: (a) Tenant's failure to meet with the
architect and to provide all required information and make necessary selections
for the expeditious development of Plans; (b) Tenant's failure to provide
comments on proposed Plans in a timely manner; (c) Tenant's request for
materials, finishes or installations requiring more time to obtain, construct or
install than Landlord's standard; or (d) Tenant's change in any Plans after the
revisions to the initial draft; or, (e) performance or completion by a party
employed by Tenant. Landlord shall not be liable for any direct or consequential
damages resulting from delayed delivery of the Premises (by reason of delayed
construction, failure or refusal of a prior tenant of the space to vacate the
Premises in accordance with its lease, or otherwise) and the scheduled
Commencement Date and the Expiration Date shall be postponed by an amount equal
to the period of delay.

                                       C-1
<PAGE>

                                    EXHIBIT C

                              RULES AND REGULATIONS

1 Any sign, lettering, picture, notice or advertisement installed within
Lessee's premises which is visible to the public from within the Building shall
be installed at Tenant's cost and in such manner, character and style as
Landlord may approve in writing. No sign, lettering, picture, notice or
advertisement shall be placed on any outside window or in a position to be
visible from outside the Building. Any object violating this paragraph may be
removed by Landlord, at Tenant's expense.

      2 In advertising or other publicity, without Landlord's prior written
consent, Tenant shall use neither the name of the Building, except as the
address of its business, nor pictures of the Building.

      3 Tenant, its customers, invitees, licensees and guests shall not obstruct
the sidewalks, entrances, passages, courts, corridors, vestibules, halls,
elevators or stairways of the Building. The sashes, sash doors, skylights,
windows and doors that reflect or admit light and air into lobbies, halls,
passageways or other public places in the Building shall not be covered or
obstructed. Tenant shall not place objects against glass partitions or doors or
windows which would be unsightly from Building corridors, lobbies, passageways,
or other public places, or from the exterior of the Building, and will promptly
remove same upon notice from Landlord. This provision does not apply to window
coverings, chosen by Tenant and approved by Landlord.

      4 Tenant shall not make noises, cause disturbances or vibrations, or use
or operate any electrical or electronic device or other device that emits sound
or other waves or disturbances, any of which may be offensive to other tenants
and occupants of the Building or which may interfere with the operation of any
device or equipment or radio or television broadcasting or reception from or
within the Building or elsewhere, and shall not place or install any
projections, antennae, aerials or similar devices inside or outside of the
Premises.

      5 Tenant shall not make any room-to-room canvass to solicit business from
other tenants in the Building and shall not exhibit, sell or offer to sell, use,
rent or exchange any item or service in or from the Premises unless ordinarily
embraced within Tenant's use of the Premises specified in the Lease.

      6 Tenant shall not waste electricity or water and agrees to cooperate
fully with Landlord to assure the most effective operation of the Building's
heating and air conditioning and shall refrain from attempting to adjust any
controls other than room thermostats installed for Tenant's use. Tenant shall
keep windows and public corridor doors closed.

      7 Door keys, not to exceed two, for doors in the Premises will be
furnished at the commencement of the Lease by Landlord. Tenant shall not fix
additional locks on doors and shall purchase duplicate keys only from Landlord
at Tenant's expense. When the Lease is terminated, Tenant shall return all keys
to Landlord and will disclose to Landlord the combination of any safes, cabinets
or vaults left in the Premises.

      8 Tenant assumes full responsibility for protecting its space from theft,
robbery and pilferage. Such protection shall include keeping doors locked where
appropriate and other means of entry to the Premises closed and secured.

      9 Peddlers, solicitors and beggars shall be reported to Landlord or as
Landlord otherwise requests.

      10 Tenant shall not install or operate machinery or any mechanical device
of a nature not directly related to Tenant's ordinary use of the Premises as
general office space without the written permission of Landlord. Wherever
heat-generating machines or equipment are used in the Premises which affect the
temperature otherwise maintained by the air conditioning system, Landlord
reserves the right to install supplementary air conditioning units to cool the
Premises, and Tenant shall pay to Landlord upon demand the cost thereof,
including the cost of installation, operation and maintenance. Tenant will not,
without Landlord's prior written consent, use any apparatus or device using
electric current in excess of 110 volts, or which increases the amount of
electricity, water or other utility otherwise furnished or supplied for use of
the Premises as general office space, nor connect to the electric current or the
water supply except through existing electrical outlets or water taps in the
Premises. If Tenant requires water, electric current or other utilities in
excess of those otherwise furnished for use of the Lease Premises as general
office space, Tenant shall first procure Landlord's written consent to the use
thereof, which consent Landlord may refuse for any reason, and Landlord may
cause metering devices to be installed in the Premises or Building for the
purpose of measuring the amount of water, electric current or other utilities
consumed for any such purpose. Tenant shall pay to Landlord upon demand the cost
of any such meters and the installation, maintenance and repair thereof and the
cost of all water, electric current or other utilities consumed as shown by said
meters, at the rates charged for such services by the suppliers thereof.

                                       D-1
<PAGE>

      11 No person or contractor not employed or approved by Landlord shall be
used to perform window washing, cleaning, decorating, repair or other work in
the Premises, Building or Project.

      12 In no event shall any person bring into the Project inflammables, such
as gasoline, kerosene, naphtha and benzene, or explosives, or any other article
of intrinsically dangerous nature. If by reason of the failure of Tenant to
comply with the provisions of this paragraph, any insurance premium payable by
Landlord for all or any part of the Project shall at any time be increased above
normal insurance premiums for insurance not covering the items aforesaid,
Landlord shall have the option to resort to one or more of the following:
terminate this Lease, require Tenant to make immediate payment for the whole of
the increased insurance premium and exercise any other remedy or combination of
remedies set forth in the Lease.

      13 Water, toilet and other plumbing fixtures shall not be used for any
purpose other than those for which they were constructed, and no sweeping,
rubbish, rags or other substance shall be thrown therein. All damage resulting
from any misuse of said fixtures by Tenant or its servants, employees, agents,
visitors or licensees shall be borne by Tenant.

      14 Tenant shall not mark, paint, drill into or in any way de face any part
of the Premises or the Building. No boring, cutting or stringing of wires or
laying of linoleum or other similar floor covering shall be permitted except
with the prior written consent of Landlord and as Landlord may direct.

      15 Except with Landlord's prior written consent, no bicycles, similar
vehicles or animals of any kind shall be brought into or kept in or about the
Premises or Project. Except for a tenant whose business in the Building is the
preparation of food for on-premises public sale and consumption, no cooking
shall be done or permitted by Tenant in the Building except that the use of
microwave ovens for the warming of prepared foods and the preparation of coffee,
tea, hot chocolate and similar items for Tenant and its employees, clients and
guests shall be permitted. Tenant shall not cause or permit any unusual or
objectionable odors to be produced or permeate the Project, Building or
Premises.

      16 The Premises shall not be used for manufacturing or for the storage of
merchandise except such storage as may be incidental to the use of the Premises
for general office purposes and any additional use specifically set forth in the
Lease. Tenant shall not occupy or permit any portion of the Premises to be
occupied as an office for a public stenographer or typist or for the manufacture
or sale of liquor, narcotics or tobacco in any form or as a medical office or as
a barber or manicure shop or as an employment bureau. Tenant shall not engage or
pay any employees on the Premises except those actually working for Tenant on
the Premises, or advertise for laborers giving an address at the Premises. The
Premises shall not be used for lodging or sleeping or for any immoral or illegal
purposes.

      17 There shall not be used by Tenant in any space or in the public halls
of the Building any hand trucks except those equipped with rubber tires and side
guards.

      18 Tenant shall not conduct any auction or permit any fine or bankruptcy
sale to be held in the Premises or store goods, wares or merchandise in the
Premises or at the Project.

      19 All freight, furniture and equipment must be moved into, within and out
of the Building under Landlord's supervision and according to such regulations
as Landlord may promulgate. All moving of freight, furniture or equipment into
or out of the Building by Tenant shall be done at such time and in such manner
as directed by Landlord or its agent. Landlord shall have the right to prescribe
the allowable weight, size, and placement details for all sales and other heavy
equipment brought into the Building. Landlord will not be responsible for loss
of, or damage to, any such safe or property from any cause, and all damage done
to the Building by moving or maintaining any such property shall be repaired at
the expense of Tenant. No office equipment, furnishings or fixtures shall be
removed from the Building during hours when the Building is closed without
obtaining Landlord's prior written permission and Landlord's security personnel
shall have the right to demand evidence of such permission from any person.

      20 Requirements of Tenant for building services, maintenance and repairs
shall be attended to only upon application to Landlord. Employees of the
Building are not permitted to perform any work or do anything outside of their
regular duties unless under special instructions from Landlord. No employees of
the Building shall admit any person, Tenant or otherwise, to any office without
specific instructions from Landlord.

      21 Tenant shall promptly notify Landlord of any accidents to or defects in
plumbing, electrical fixtures, heating apparatus and/or air conditioning
equipment so that the same may be attended to properly.

      22 Landlord reserves the right to close and keep locked all entrance and
exit doors of the Project at all times which are not ordinary business hours.
For purposes of this paragraph, "Ordinary business hours" in the Building shall
be from 7:00 a.m. to 6:00 p.m. on Mondays through Fridays but excluding any day
which is a legal holiday.

                                       D-2
<PAGE>

      23 On Saturdays, Sundays, legal holidays and other days during the hours
the Building may be closed after ordinary business hours, access to the Project
or Building or to the halls, corridors, elevators or stairways will be
controlled by Landlord through the use of security personnel or access cards.
Such personnel will have the right to demand of any and all personal seeking
access to the Building proper identification to determine if they have right of
access to the Project. Landlord shall in no case be liable for damages wherein
admission to the Building has been refused during the hours the Building may be
closed after ordinary business hours by reason of a tenant's failing to properly
identify himself or herself to the security personnel, or because the Building
was locked and closed to access by a tenant, a tenant's employees and the
general public.

      24 A directory in the main lobby of the Building shall be provided to
display the name and location of Building tenants only. Landlord reserves the
right to exclude any other name therefrom and also to make a reasonable charge
for each name, in addition to Tenant's name, placed upon such directory at
Tenant's request.

      25 Tenant shall not be entitled, by virtue of this Lease, to use or
patronize any service, business or facility located in the Building, but may
become entitled to use or patronize the same by satisfactory arrangements with,
and subject to all of the terms and conditions imposed by, the operator of such
business or facility.

      26 Landlord reserves the right to exclude or expel from the Building any
person who, in the Landlord's judgment, is intoxicated or under the influence of
liquor or drugs, or who shall in any manner violate any of the rules and
regulations contained herein.

      27 Landlord reserves the right at any time and from time to time to waive
any of the Building rules and regulations.

      28. There shall be no smoking anywhere in the Building. Tenant shall
cooperate with Landlord and landlord's agents to enforce this rule.

                                       D-3
<PAGE>

                                       F-4
<PAGE>

      insulated, fireproofed or surfaced with any asbestos-containing materials.
      Landlord shall provide the Premises arid all other areas of the Premises
      where Tenant places equipment free of hazardous materials

34.   Express Waiver of Landlord's Lien. Landlord hereby expressly waives its
      Landlord's lien and any and all rights granted by or under any present or
      future laws to Levy or distrain for rent, in arrears, in advance, or both,
      upon any or all personalty, including, but not limited to [supporting
      towers, antennas, satellite dish(es). Connecting Equipment] equipment,
      trade fixtures, furniture and other personal property at Tenant or any
      assignee or subtenant of Tenant in the Premises.

35.   Allowable Use of Certain Hazardous Materials. Tenant may use and store the
      following materials in the ordinary course of its business: fuel for the
      generator(s) in order to supply an uninterrupted power source (UPS); acid
      contained within batteries for back-up power; reasonable amounts of
      standard cleaning fluid and materials customarily used in conjunction with
      business machines; cleaning supplies in reasonable quantities; coolant for
      any Tenant installed HVAC system, or other materials used in fire
      suppression and any other materials deemed necessary to Tenant's business.
      Landlord may use, but not store, art the Premises the following materials
      in the ordinary course of business: cleaning supplies, insecticides,
      fungicides, and rodenticides. Tenant shall not indemnify Landlord for
      releases of any hazardous materials that exist on the Premises, at the
      time of execution of this Lease or are brought on the Premises, into the
      building, or on, in or under the land upon which the Building is located
      by anyone other than Tenant, its employees, agents, or third-party
      contractors. This provision shall survive the expiration or sooner
      termination of this Lease.

                                  TENANT:  Advanced Telecommunications Inc.
                                           A Delaware corp.

                                      By: /s/ S. C. Tivari
        SATISH C. TIVARI                  ---------------------------------
      V.P. ENGINEERING AND
     NETWORK IMPLEMENTATION           Its:
ADVANCED TELECOMMUNICATIONS, INC.         ---------------------------------
    720 2ND AVE S. SUITE 1200
      MINNEAPOLIS, MN 55402           Date     12/27/99
                                           -------------------------------------

                                  LANDLORD:

                                      SOFI-IV SIM OFFICE INVESTORS II, LP, an
                                      Delaware limited partnership

                                      By:   Scottsdale Property Management 97,
                                            L.L.C., an Arizona limited liability
                                            company, Agent

                                            By /s/ [ILLEGIBLE]
                                               ---------------------------------
                                               Authorized signatory

                                      Date     12-30-99
                                           -------------------------------------

Subject to Landlord's
Receipt of:

-- Security deposit

-- 1st Month's Rent

-- Generator/HVAC Fee<PAGE>
                                                                 Exhibit 10.1.12

                                 LEASE AGREEMENT

                                     BETWEEN

                               SEATTLE TELECOM LLC

              A Limited Liability Company of the State of Delaware

                                       AND

                        Advanced Telecommunications, Inc.

                             A Delaware Corporation

                            DATED: December ___, 1999

                                  PREPARED BY:

                 SCHUMANN, HANLON, DOHERTY, McCROSSIN & PAOLINO
                        30 MONTGOMERY STREET - 15TH FLOOR
                          JERSEY CITY, NEW JERSEY 07302
                                  201-434-2000

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            THIS LEASE dated December ___, 1999 made by and between SEATTLE
TELECOM LLC, a limited liability company of the State of Delaware, having
offices at 750 Lexington Avenue, 28th Floor, New York, New York 10022
("Landlord") and ADVANCED TELECOMMUNICATIONS, INC., a Delaware Corporation
having an office at 730 Second Avenue South, Suite 1200, Minneapolis, Minnesota
55402 ("Tenant").

                                    ARTICLE 1
                                   DEFINITIONS

            1.01. As used in this Lease (including in all Exhibits and any
Riders attached hereto, all of which shall be deemed to be part of this Lease)
the following words and phrases shall have the meanings indicated:

            A. Advance Rent: One (1) month's Fixed Rent.

            B. Additional Rent: All amounts that become payable by the Tenant to
Landlord hereunder other than the Fixed Rent.

            C. Broker: Grubb & Ellis Company, 600 University, 1 Union Square,
Suite 1800, Seattle, Washington 98101-4159.

            D. Building: 1200 Third Avenue, Seattle, Washington 98101,
consisting of approximately 151,070 square feet ("s.f.").

            E. Business Days: All days except Saturdays after 1:00 P.M.,
Sundays, days observed by the federal or state government as legal holidays and
such other days as shall be designated as holidays by the applicable operating
engineer. union or building service employees union contract, if any.

            F. Business Hours: Generally customary daytime business hours but
not before 8:00 A.M. or after 6:00 P.M. and Saturdays 9:00 A.M. to 1:00 P.M.,
Pacific Time.

            G. Calendar Year: Any consecutive twelve-month period commencing on
January 1.

            H. Commencement Date: January 1, 2000

            I. Common Areas: All areas, spaces and improvements in the Building
and on the Land which Landlord makes available from time to time for the common
use and benefit of the tenants and occupants of the Building and which are not
exclusively available for use by a single tenant or occupant, including, without
limitation, parking areas, roads, walkways, landscaped and planted areas,
community rooms, if any, the managing agent's office, if any, and public rest
rooms, if any.

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            J. Demised premises: 12,645 s.f. located on the tenth (10th) floor
of the Building as shown on Exhibit B but excluding certain riser space,
available exclusive to US West Communications, Inc. under the US West Lease, as
further depicted on Exhibit B. The Demised Premises shall also mean any portion
of the interior or exterior of the Building or any facilities of the Building,
utilized by Tenant pursuant to the provisions of this Lease, including (without
limitation) any roof areas, interior or exterior generator or battery areas, and
riser and shaftway spaces.

            K. Expiration Date: The date that is the day before the tenth (10th)
anniversary of the Commencement Date if the Commencement Date is the first day
of a month, or the tenth (10th) anniversary of the last day of the month in
which the Commencement Date occurs if the Commencement Date is not the first day
of a month. However, if the Term is extended by Tenant's effective exercise of
Tenant's rights, if any, to extend the Term, the "Expiration Date" shall be
changed to the last day of the latest extended period as to which Tenant shall
have effectively exercised its right to extend the Term. For the purposes of
this definition, the earlier termination of this Lease shall not affect the
"Expiration Date."

            L. Fixed Rent:

                  (i) $34.00 per square foot or Four Hundred Twenty Nine
Thousand Nine Hundred Thirty & 00/100 ($429,930.00) Dollars per year for the
period commencing on the Commencement Date and ending on the day before the
fifth (5th) anniversary of the Commencement Date, payable at the rate of
Thirty-Five Thousand Eight Hundred Twenty-Seven & 50/100 ($35,827.50) Dollars
per month as hereinafter provided; and

                  (ii) $37.00 per s.f. or Four Hundred Sixty-Seven Thousand
Eight Hundred Sixty-Five & 00/100 ($467,865.00) Dollars per year for the period
commencing with the fifth (5th) anniversary of the Commencement Date and ending
on the Expiration Date, payable at the rate of Thirty-Eight Thousand Nine
Hundred Eighty-Eight & 75/100 ($38,988.75) Dollars per month as hereinafter
provided.

            M. Insurance Requirements: Rules, regulations, orders and other
requirements of the applicable board of underwriters and/or the applicable fire
insurance rating organization and/or any other similar body performing the same
or similar functions and having jurisdiction or cognizance over the Land and
Building, whether now or hereafter in force.

            N. Land: The land described in Exhibit A, upon which the Building is
located.

            O. Legal Requirements: Laws and ordinances of all federal, state and
local governments, and rules, regulations, orders and

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directives of all departments, subdivisions, bureaus, agencies or offices
thereof, and of any other governmental, public, quasi-public authorities having
jurisdiction over the Land and Building now in force or which may be in force
hereafter during the Term of this Lease.

            P. Mortgage: A mortgage and/or a deed of trust.

            Q. Mortgagee A holder of a mortgage or a beneficiary of a deed of
trust.

            R. Operating Expenses: All costs and expenses, and taxes thereon, if
any, paid or incurred by Landlord in connection with the Building, the Building
utility and service systems, the sidewalks, curbs, plazas and other areas
adjacent to the Building, and with respect to the services provided tenants,
including, without limitation: (i) salaries, wages and bonuses paid to, and the
cost of any hospitalization, medical, surgical, union and general welfare,
benefits (including group life insurance), any pension, retirement or life
insurance plan or any other benefit or similar expense relating to employees of
Landlord engaged exclusively in the operation, cleaning, repairs, safety,
management, security or maintenance of the Land and/or the Building or in
providing services to tenants; (ii) social security, unemployment and other
payroll taxes, the cost of providing disability and worker's compensation
coverage imposed by any requirements of law, union contract or otherwise with
respect to said employees; (iii) the cost of casualty, rent, liability, steam
boiler explosion, electrical arcing, systems breakdown, fidelity, plate glass
and any other insurance; (iv) the cost of repairs, replacements, maintenance and
painting; (v) expenditures for improvements and equipment which are made by
reason of Legal Requirements or Insurance Requirements; (vi) the cost or rental
of all building and cleaning supplies, tools, materials and equipment; (vii) all
costs, charges and expenses incurred by Landlord in connection with any change
of any company providing electricity service, including, without limitation,
maintenance, repair, installation and service costs associated therewith: (viii)
the cost of uniforms, work clothes and dry cleaning; (ix) window cleaning,
concierge, guard, watchman or other security personnel, service or system, if
any; (x) management fees calculated at the rate of three (3%) percent per annum
of Rent; (xi) charges of independent contractors performing work included within
this definition of operating Expenses; (xii) telephone and stationery; (xiii)
legal, accounting and other professional fees and disbursements incurred in
connection with the operation and management of the Building and Land; (xiv)
association fees and dues; (xv) depreciation of movable equipment used in the
operation, cleaning, repair, safety, management, security or maintenance of the
Building; (xvi) the cost of painting and/or decorating and/or other maintenance
of the public or common areas of the Building and Land; (xvii) the cost of all
interior and exterior gardening and landscaping of the Building and Land;
(xviii) the cost of maintenance, repair and/or replacement of the Building
facade; (xix) the cost of pest

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and vermin extermination for the common areas of the Building and the Land; and
(xx) Utility Costs (as hereinafter defined). Operating Costs which are capital
in nature shall be amortized over their useful life and allocated over the
balance of the Term at the prime interest rate, as declared by Chase Bank, NA in
New York, New York plus two (2%) percent per annum. However, that Operating
Expenses shall exclude or have deducted from them, as the case may be the
following:

            (a)   amounts actually received by Landlord through insurance
                  proceeds, condemnation awards, warranties and service
                  contracts, or otherwise, to the extent they are compensation
                  for sums previously included in Operating Expenses hereunder;

            (b)   brokerage commissions;

            (c)   Real Estate Taxes;

            (d)   the cost of electricity furnished to the Demised Premises or
                  any other space leased to tenants as reasonably estimated by
                  Landlord;

            (a)   financing and refinancing costs, rents payable under the
                  Master Lease or any Superior Lease, and mortgage interest and
                  mortgage payments due under any Mortgage,

            (f)   depreciation except as otherwise expressly herein provided;

            (g)   cost and expenses incurred in connection with the enforcement
                  of leases and disputes with tenants in the Building, including
                  without limitation, court costs, attorney's fees and
                  disbursements;

            (h)   cost and expenses incurred in connection with leasing or
                  re-leasing space in the Building such as space planning,
                  architectural, engineering, attorneys' fees and advertising
                  and promotional expenses unless due to Tenant's default;

            S. Permitted Use: Executive and general office use, installation,
operation, modification and maintenance of equipment and facilities in
connection with Tenant's Telecommunications business including, but not limited
to, a Telecommunications switch.

            T. Person: A natural person or persons, a partnership, a
corporation, or any other form of business or legal association or entity.

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            U. Real Estate Taxes: The real estate taxes, assessments and special
assessments imposed upon the Building and Land by any federal, state, municipal
or other governments or governmental bodies or authorities and any alternative
or substitute charges. Any expenses incurred by Landlord in contesting such
taxes or assessments and/or the assessed value of the Building and Land, which
expenses shall be allocated to the period of time to which such expenses relate.
Tenant shall not be obligated or required to pay any tax on the income or
receipts of Landlord. If at any time during the Term the methods of taxation
prevailing on the date hereof shall be altered so that in lieu of, or as an
addition to or as a substitute for, the whole or any part of such real estate
taxes, assessments and special assessments now imposed on real estate there
shall be levied, assessed or imposed (a) a tax, assessment, levy, imposition,
license fee or charge wholly or partially as a capital levy or otherwise on the
rents received therefrom, or (b) any other such additional or substitute tax,
assessment, levy, imposition or charge, then all such taxes, assessments,
levies, impositions, fees or charges or the part thereof so measured or based
shall be deemed to be included within the term "Real Estate Taxes" for the
purposes hereof.

            V. Rent: The Fixed Rent and Additional Rent.

            W. Rules and Regulations: The reasonable rules and regulations that
may be promulgated by Landlord from time to time, as same may be reasonably
changed by Landlord from time to time. The Rules and Regulations now in effect
are attached hereto as Exhibit C.

            X. Security Deposit: Two Hundred Fourteen Thousand Nine Hundred
Sixty-Five & 00/100 ($214,965.00) Dollars, i.e. six (6) months Fixed Rent.

            Y. Successor Landlord: As defined in Section 9.03.

            Z. Superior Lease: Any lease to which this Lease is, at the time
referred to, subject and subordinate.

            AA. Superior Lessor: The lessor of a Superior Lease or its successor
in interest, at the time referred to.

            BB. Superior Mortgage: Any Mortgage to which this Lease is, at the
time referred to, subject and subordinate.

            CC. Superior Mortgagee: The Mortgagee of a Superior Mortgage at the
time referred to.

            DD. Tenant's Fraction: 8.3703%

            If the size of the Demised Premises or the Building shall be changed
from the initial size thereof, due to any taking, any construction or alteration
work, exercise of an expansion option hereunder or otherwise, the Tenant's
Fraction shall be automatically

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adjusted to the fraction the numerator of which shall be the square footage of
the Demised Premises and the denominator of which shall be the square footage of
the Building;

            EE. Tenant's Initial Improvements: The facilities, materials and
work undertaken pursuant to Article V.

            FF. Tenant's Property: As defined in Section 16.02.

            GG. Term: The period commencing on the Commencement Date and ending
11:59 p.m. of the Expiration Date, but in any event the Term shall end on the
date when this Lease is earlier terminated.

            HH. Unavoidable Delays: A delay arising from or as a result of a
strike, lockout, or labor difficulty, explosion, sabotage, riot or civil
commotion, act of war, fire or other catastrophe or any other cause beyond the
reasonable control of either party, provided that the party asserting such
Unavoidable Delay has exercised its best efforts to minimize such delay.

            II. Utility costs: Landlord's cost (incurred directly or through
independent contractors) for all electricity (to the extent Landlord is not
directly reimbursed therefor by individual tenants), steam, water, gas or other
fuel and utilities supplied to the Building or the Land, including in each case,
any surcharges, fuel adjustments and taxes payable by Landlord in connection
therewith.

            JJ. US West Lease: Lease agreement, dated September 24, 1999,
between Landlord and US West Communications, Inc. for a portion of 1200 Third
Avenue, Seattle, Washington.

                                    ARTICLE 2
                                 DEMISE AND TERM

            2.01. Landlord hereby leases to Tenant, and Tenant hereby leases
from Landlord, the Demised Premises, for the Term. Promptly following the
Commencement Date, at the option of the Landlord, the parties hereto shall enter
into an agreement in form and substance satisfactory to Landlord and Tenant
setting forth the Commencement Date.

                                    ARTICLE 3
                                      RENT

            3.01. Tenant shall pay the Fixed Rent in equal monthly installments
in advance on the first day of each and every calendar month during the Term. If
the Commencement Date occurs on a day other than the first day of a calendar
month, the Fixed Rent for the partial calendar month at the commencement of the
Term shall be prorated. Upon execution of the Lease, Tenant shall pay the
Advance Rent which shall be applied to the first month's Fixed Rent following
the Commencement Date.

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            3.02. The Rent shall be paid in lawful money of the United States to
Landlord or Landlord's agent at its office, or such other place, as Landlord
shall designate by notice to Tenant. Tenant shall pay the Rent promptly when due
without notice or demand therefor and without any abatement, deduction or setoff
for any reason whatsoever, except as may be expressly provided in this Lease. If
Tenant makes any payment to Landlord by check, same shall be by check of Tenant
and Landlord shall not be required to accept the check of any other person, and
any check received by Landlord shall be deemed received subject to collection.
If any check is mailed by Tenant, Tenant shall post such check in sufficient
time prior to the date when payment is due so that such check will be received
by Landlord on or before the date when payment is due.

            3.03. No payment by Tenant or receipt or acceptance by Landlord of a
lesser amount than the correct Rent shall be deemed to be other than a payment
on account, nor shall any endorsement or statement on any check or any letter
accompanying any check or payment be deemed an accord and satisfaction, and
Landlord may accept such check or payment without prejudice to Landlord's right
to recover the balance or pursue any other remedy in this Lease or at law
provided.

            3.04. If Tenant is in arrears in payment of Rent, Tenant waives
Tenant's right, if any, to designate the items to which any payments made by
Tenant are to be credited, and Landlord may apply any payments made by Tenant to
such items as Landlord sees fit, irrespective of and notwithstanding any
designation or request by Tenant as to the items to which any such payments
shall be credited. Notwithstanding the foregoing, in the event Tenant in good
faith disputes a liability asserted by Landlord, Tenant may designate the
item(s) to which its payments should be credited provided Tenant's designation
does not prejudice Landlord's position with respect to the dispute.

            3.05. Any payment due Landlord under this Lease which is not paid
within five (5) days of written notice of non-payment shall, from the due date
until such payment is received by Landlord, bear interest at the prime rate of
Chase Bank, NA, in New York plus 6% per annum (the "Late Payment Rate"),
provided however, the aforesaid interest shall not be imposed unless Landlord
fails to receive an overdue payment within five (5) days of Landlord's written
notice to Tenant thereof.

                                    ARTICLE 4
                             USE OF DEMISED PREMISES

            4.01. Tenant shall use and occupy the Demised Premises for the
Permitted Use, and Tenant shall not use or permit or suffer the use of the
Demised Premises or any part thereof for any other purpose.

            4.02. If any governmental license or permit, other than a
Certificate of Occupancy, shall be required for the proper and lawful conduct of
Tenant's business in the Demised Premises or any part thereof, Tenant shall duly
procure and thereafter maintain such license

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or permit, and submit the same to Landlord for inspection. Tenant shall at all
times comply with the terms and conditions of each such license or permit.
Tenant shall not at any time use or occupy, or suffer or permit anyone to use or
occupy the Demised Premises, or do or permit anything to be done in the Demised
Premises, in any manner which (a) violates the Certificate of occupancy for the
Demised Premises or for the Building; (b) causes or is liable to cause injury to
the Building or any equipment, facilities or systems therein; (c) constitutes a
violation of the Legal Requirements or Insurance Requirements; (d) impairs or
tends to impair the character, reputation or appearance of the Building as a
first-class building; (e) impairs the proper and economic maintenance,
operation and repair of the Building and/or its equipment facilities or
systems; or (f) interferes with the Quiet Enjoyment rights of the other tenants
in the Building.

                                    ARTICLE 5
                        CONDITION OF THE DEMISED PREMISES

            5.01. Landlord acknowledges that following execution of the Lease,
Tenant may be required to perform certain construction ("Tenant's Initial
Improvements") in the Demised Premises. Tenant, at its sole cost and expense,
shall prepare complete construction drawings and specifications including
architectural, mechanical, engineering, electrical and life safety drawings
("Tenant's Plans") sufficient to obtain a building permit. Tenant's Plans shall
be subject to Landlord's prior written approval. Tenant shall manage the
construction bidding process and engage a contractor mutually acceptable to
Landlord and Tenant to perform Tenant's Initial Improvements. As an express
condition precedent to construction of Tenant's Initial Improvements, Tenant
shall (i) provide Landlord with a Certificate of Insurance in the amount and
under the terms set forth in Article 13 hereof and shall comply with all of the
insurance and indemnity provisions Set forth therein and (ii) a full payment and
performance bond, issued by a surety company satisfactory to Landlord and in
form and substance satisfactory to Landlord in favor of Landlord for the
construction of Tenant's Initial Improvements. Landlord shall not be entitled to
any construction management fee, but shall be entitled to recover from Tenant
the out-of-pocket or the actual cost of architectural, engineering and legal
review of Tenant's plans. Any work performed by Tenant hereunder shall comply
with any and all governmental rules and regulations including, but not limited
to, rules and regulations pertaining to the Americans with Disabilities Act.

            5.02. Tenant has inspected the Demised Premises and accepts the same
"as is" in their presently existing condition, and Landlord shall have no
obligation to perform any work in order to prepare the Demised Premises for
Tenant's occupancy, except that Landlord shall, on or prior to the commencement
date, insure that the Demised Premises in other areas of the Building that will
be used by Tenant, shall be free of asbestos containing material and other
hazardous materials.

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            5.03. Tenant shall occupy and take possession of the Demised
Premises promptly on the Commencement Date. Except as expressly provided to the
contrary in this Lease, the taking of possession by Tenant of the Demised
Premises shall be conclusive evidence as against Tenant that the Demised
Premises and the Building were in good and satisfactory condition at the time
such possession was taken.

            5.04. Tenant shall have the right to install conduits and cables
within the vertical risers of the building to the demised premises required for
Tenant's Permitted Use pursuant to Tenant's Riser Plan (the "Riser Plan"),
approved by Landlord. Such right is expressly subject to (i) delivery of plans
and specifications indicating in specific detail the amount, location, size and
other information requested by Landlord relating to the installation of such
conduits; (ii) Landlord's prior written approval of such plans and
specifications, which approval shall be in Landlord's sole reasonable
discretion, and (iii) the approval of any and all governmental authorities
having jurisdiction over such work. Tenant shall be responsible for any and all
costs associated with the performance of such work. Landlord will have the
absolute right to be present during the course of the performance of any such
work, to halt such work in the event that Tenant fails to comply with Landlord's
approved plans and specifications and to inspect such work from time to time as
Landlord deems fit. Tenant shall be responsible for any and all costs,
associated with Landlord's inspection or approval of Tenant's Plans, the Riser
Plan or the performance of Tenant's Initial Improvements. In the event that such
work requires the penetration of surfaces within the Building, Tenant shall use
its best efforts to conceal such work and the surface finish shall be returned
to the same condition as it was at the time that Tenant commenced the work.
Future additional Riser space may be provided to Tenant subject to the
conditions set forth above as to the Riser Plan and subject further to (i) the
availability of additional Riser space in Landlord's sole and absolute
discretion; (ii) the Building rules and regulations; and (iii) payment of Riser
fees as determined by Landlord in its sole and absolute discretion. There shall
be no charges for Tenant's use of the Riser space pursuant to the Riser Plan.

            5.05 Tenant shall, at its sole cost and expense, install a life
safety system for the Demised Premises (including, without limitation, fire
detection and fire suppression system, consisting of a pre-action sprinkler or
FN200) which life safety system shall be connected to the life safety system for
the Building.

            5.06. Landlord reserves the right, at any time and from time to
time, to increase, reduce or change the number, type, size, location, elevation,
nature and use of any of the Common Areas of the Building and any other
buildings and other improvements on the Land, including without limitation the
right to move and/or remove same, provided same shall not unreasonably block or
interfere with Tenant's means of ingress or egress to and from the Demised
Premises.

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                                    ARTICLE 6
                       TAX AND OPERATING EXPENSE PAYMENTS

            6.01. Tenant shall pay, as Additional Rent, to Landlord, as
hereinafter provided, Tenant's share of the Real Estate Taxes. Tenant's share of
the Real Estate Taxes shall be the Real Estate Taxes for the Building and Land
for the period in question. multiplied by the Tenant's Fraction. The Real Estate
Taxes for the Building and Land shall be calculated as if the full amount of
such Real Estate Taxes is payable by tenants occupying 95% of the square footage
of the Building. By way of illustration and not by way of limitation, if the
Real Estate Taxes for the Building and Land amount to $100,000.00 and, further,
if Tenant's Real Estate Fraction is 7%, then Tenant's proportionate share of
Real Estate Taxes would be $7,368.42, i.e. $100,000.00 .95 x 7%. If any portion
of the Building shall be exempt from all or any part of the Real Estate Taxes,
then for the period of time when such exemption is in effect, the rentable space
on such exempt portion shall be excluded when making the above computations in
respect of the part of the Real Estate Taxes for which such portion shall be
exempt. Landlord shall estimate the annual amount of Tenant's proportionate
share of the Real Estate Taxes (which estimate may be changed by Landlord at any
time and from time to time), and Tenant shall pay to Landlord 1/12th of the
amount so estimated on the first day of each month in advance. Tenant shall also
pay to Landlord on demand from time to time the amount which, together with said
monthly installments, will be sufficient in Landlord's estimation to pay
Tenant's proportionate share of any Real Estate Taxes thirty (30) days prior to
the date when such Real Estate Taxes shall first become due. When the amount of
any item comprising Real Estate Taxes is finally determined for a real estate
fiscal tax year, Landlord shall submit to Tenant a statement in reasonable
detail of the same, and the figures used for computing Tenant's proportionate
share of the same, and if Tenant's proportionate share so stated is more or less
than the amount theretofore paid by Tenant for such item based on Landlord's
estimate, Tenant shall pay to Landlord the deficiency, or Landlord shall refund
to Tenant the excess, within ten (10) Business Days after submission of such
statement provided Tenant is not then in default of the Lease. Any Real Estate
Taxes for a real estate fiscal tax year, a part of which is included within the
Term and a part of which is not so included, shall be apportioned on the basis
of the number of days in the real estate fiscal tax year included in the Term,
and the real estate fiscal tax year for any improvement assessment will be
deemed to be the one-year period commencing on the date when such assessment is
due, except that if any improvement assessment is payable in installments, the
real estate fiscal tax year for each installment will be deemed to be the
one-year period commencing on the date when such installment is due.

            6.02. Tenant shall pay, as Additional Rent, to Landlord, as
hereinafter provided, Tenant's share of the Operating Expenses. Tenant's share
of the Operating Expenses shall be the Operating Expenses for the period in
question, multiplied by Tenant's Fraction. Operating Expenses shall be
calculated as if the full amount of such Operating

                                       10
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Expenses is payable by tenants occupying 95% of the square footage of the
Building. By way of illustration and not by way of limitation, if the Operating
Expenses amount to $l00,000.00 and further if Tenant's Operating Fraction is 7%,
then Tenant's proportionate share of Operating Expenses would be $7,368.42, i.e.
$100,000.00 / .95 x 7%. Landlord shall estimate Tenant's annual proportionate
share of the Operating Expenses (which estimate may be reasonably changed by
Landlord from time to time), and Tenant shall pay to Landlord 1/12th of the
amount so estimated on the first day of each month in advance. If at any time
Landlord changes its estimate of Tenant's proportionate share of the Operating
Expenses for the then current Calendar Year or partial Calendar Year, Landlord
shall give notice to Tenant of such change and within ten (10) Business Days
after such notice Landlord and Tenant shall adjust for any overpayment or
underpayment during the prior months of the then current Calendar Year or
partial Calendar Year. After the end of each Calendar Year, including any
partial Calendar Year at the beginning of the Term, and after the end of the
Term, Landlord shall submit to Tenant a statement in reasonable detail stating
Tenant's proportionate share of the Operating Expenses for such Calendar Year,
or partial Calendar Year in the event the Term shall begin on a date other than
a January 1st and/or end on a date other than a December 31st, as the case may
be, and stating the Operating Expenses for the period in question and the
figures used for computing Tenant's proportionate share, and if Tenant's
proportionate share so stated for such period is more or less than the amount
paid for such period, Tenant shall pay to Landlord the deficiency, or Landlord
shall refund to Tenant the excess, within ten (10) Business Days after
submission of such statement of Tenant's proportionate share provided Tenant is
not then in default of the Lease.

            6.03. Each such statement given by Landlord pursuant to Section 6.01
or Section 6.02 shall be conclusive and binding upon Tenant unless within one
(1) year after the receipt of such statement Tenant shall notify Landlord that
it disputes the correctness of the statement, specifying the particular respects
in which the statement is claimed to be incorrect. If such dispute is not
settled by agreement, either party may submit the dispute to arbitration as
provided in Article 36. Pending the determination of such dispute by agreement
or arbitration as aforesaid, Tenant shall, within ten (10) Business Days after
receipt of such statement, pay the Additional Charges in accordance with
Landlord's statement, without prejudice to Tenant's position. If the dispute
shall be determined in Tenant's favor, Landlord shall within ten (10) Business
Days pay to Tenant the amount of Tenant's overpayment resulting from compliance
with Landlord's statement.

                                    ARTICLE 7
                                  COMMON AREAS

            7.01. Landlord will operate, manage, equip, light, repair and
maintain, or cause to be operated, managed, equipped, lighted, repaired and
maintained, the Common Areas for their intended purposes. Landlord reserves the
right, at any time and from time do time, to

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construct within the Common Areas kiosks and to install vending machines,
telephone booths, benches and the like, provided same shall not unreasonably
block or interfere with Tenant's means of ingress or egress to and from the
Demised premises; provided however, Landlord shall not cause a material adverse
impact on the conduct of Tenant's business.

            7.02. Tenant, its subtenants and concessionaires, and their
respective officers, employees, agents, customers and invitees, shall have the
non-exclusive right to use the Common Areas, in common with Landlord and all
others to whom Landlord has granted or may hereafter grant such right, but
subject to the Rules and Regulations. Landlord reserves the right, at any time
and from time to time, to close temporarily all or any portions of the Common
Areas when in Landlord's reasonable judgment any such closing is necessary or
desirable (a) to make repairs or changes or to effect construction, (b) to
prevent the acquisition of public rights in such areas, or (c) to protect or
preserve natural persons or property. Landlord may do such other acts in and to
the Common Areas as in its judgment may be desirable to improve or maintain
same. In connection with the foregoing, Landlord shall make reasonable efforts
to avoid a material adverse impact on the conduct of Tenant's business and shall
provide adequate ingress and egress to the Demised Premises.

                                    ARTICLE 8
                                    SECURITY

            8.01. Upon execution of this Lease, Tenant shall deposit with
Landlord the security Deposit for the full and faithful payment and performance
by Tenant of Tenant's obligations under this Lease. Such Security Deposit shall
be by certified funds or an irrevocable, evergreen letter of credit issued (in
favor of Superior Mortgagee) by a federally chartered bank in Seattle,
Washington or such other location approved by Landlord. If Tenant defaults in
the full and prompt payment and performance of any of its obligations under this
Lease, including, without limitation, the payment of Rent, Landlord may use,
apply or retain the whole or any part of the Security Deposit so deposited to
the extent required for the payment of any Rent or any other sums as to which
Tenant is in default or for any sum which Landlord may expend or may be required
to expend by reason of Tenant's default in respect of any of Tenant's
obligations under this Lease, including, without limitation, any damages or
deficiency in the reletting of the Demised Premises, whether such damages or
deficiency accrue before or after summary proceedings or other re-entry by
Landlord. If Landlord shall so use, apply or retain the whole or any part of the
Security Deposit, Tenant shall, upon demand, immediately deposit with Landlord a
sum equal to the amount so used, applied and retained as the Security Deposit.
If Tenant shall fully and faithfully pay and perform all of Tenant's obligations
under this Lease, the Security Deposit or any balance thereof to which Tenant is
entitled shall be returned or paid over to Tenant, without interest, after the
date on which this Lease shall expire or sooner end or terminate, and after
delivery to Landlord of

                                       12
<PAGE>

entire possession of the Demised Premises. In the event of any sale or leasing
of the Building and/or the Land, Landlord shall have the right to transfer the
Security Deposit to which Tenant is entitled to the vendee or lessee and
Landlord shall thereupon be released by Tenant from all liability for the return
or payment thereof and Tenant shall look solely to the new Landlord for the
return or payment of the same. The provisions hereof shall apply to every
transfer or assignment made of the same to a new Landlord. The Tenant shall not
assign or encumber or attempt to assign or encumber the monies deposited herein
as security, and neither Landlord nor its successors or assigns shall be bound
by any such assignment, encumbrance, attempted assignment or attempted
encumbrance. Notwithstanding the foregoing, provided Tenant's net worth, as
certified by a reputable accounting firm, exceeds $10,000,000.00, then
commencing on the fifth (5th) anniversary of the Commencement Date and for each
anniversary date thereafter for so long as Tenant's net worth continues to
exceed $10,000,000.00 the security Deposit shall be reduced at the rate of
twenty (20%) percent per year.

                                    ARTICLE 9
                                  SUBORDINATION

            9.01. This Lease and all rights of Tenant hereunder are and shall be
subject and subordinate to all Mortgages affecting the Land and/or Building,
whether or not such Mortgages shall also cover other lands and/or buildings, to
each and every advance made or hereafter to be made under such Mortgages, to all
renewals, modifications, replacements and extensions of such Mortgages and
spreaders and consolidations of such Mortgages, to all present or future ground
leases and grants of term of the Building, Land or parts thereof. The provisions
of this Section 9.01 shall be self-operative and no further instrument of
subordination shall be required. In confirmation of such subordination, Tenant
shall promptly execute, acknowledge and deliver any instrument that Landlord or
the Mortgagee of any such Mortgage or any of their respective successors in
interest may reasonably request to evidence such subordination; and if Tenant
fails to execute, acknowledge or deliver any such instruments within ten (10)
Business Days after request therefor, Tenant hereby irrevocably constitutes and
appoints Landlord as Tenant's attorney-in-fact, coupled with an interest, to
execute and deliver any such instruments for and on behalf of Tenant. Landlord
hereby agrees to obtain a Non-disturbance Agreement ("Non-disturbance
Agreement") from all Superior Mortgagees with respect to Superior Mortgages
heretofore given by Landlord on the standard forms provided by such Superior
Mortgagees. The Non-disturbance Agreement shall provide, among other matters,
that should such Superior Mortgagee succeed to the rights of the Landlord under
this Lease, this Lease and the rights of Tenant hereunder shall not be
disturbed, but shall continue in full force and effect so long as no default
hereunder shall have occurred.

            9.02. If any act or omission of Landlord would give Tenant the
right, immediately or after lapse of a period of time, to cancel or terminate
this Lease, or to claim a partial or total eviction, Tenant

                                       13
<PAGE>

shall not exercise such right (a) until it has given written notice of such act
or omission to Landlord, and each Superior Mortgagee and each Superior Lessor
whose name and address shall previously have been furnished to Tenant, and (b)
until a reasonable period for remedying such act or omission shall have elapsed
following the giving of such notice and following the time when such Superior
Mortgagee, or superior Lessor shall have become entitled under such Superior
Mortgage, or Superior Lease, as the case may be, to remedy the same (which
reasonable period shall in no event be less than the period to which Landlord
would be entitled under this Lease or otherwise, after similar notice, to effect
such remedy), provided such Superior Mortgagee, or Superior Lessor shall elect
to remedy with due diligence give Tenant notice of intention to, and commence
and continue to, remedy such act or omission.

            9.03. If any Superior Lessor or Superior Mortgagee shall succeed to
the rights of Landlord under this Lease, whether through possession or
foreclosure action or delivery of a new lease or deed, then at the request of
such party so succeeding to Landlord's rights ("Successor Landlord") and upon
such Successor Landlord's written agreement to accept Tenant's attornment,
Tenant shall attorn to and recognize such Successor Landlord as Tenant's
Landlord under this Lease and shall promptly execute and deliver any instrument
that such Successor Landlord may reasonably request to evidence such attornment.
Upon such attornment this Lease shall continue in full force and effect as a
direct lease between the Successor Landlord and Tenant upon all of the terms,
conditions and covenants as are set forth in this Lease except that the
Successor Landlord shall not (a) be liable for any previous act or omission of
Landlord under this Lease; (b) be subject to any offset, not expressly provided
for in this Lease, which theretofore shall have accrued to Tenant against
Landlord; or (c) be bound by any previous modification of this Lease or by any
previous prepayment of more than one month's Fixed Rent or Additional Rent,
unless such modification or prepayment shall have been expressly approved in
writing by the Successor Landlord.

            9.04. If any then present or prospective Superior Mortgagee shall
require any modification(s) of this Lease, Tenant shall promptly execute and
deliver to Landlord such instruments effecting such modification(s) as Landlord
shall request, provided that such modification(s) do not adversely affect in any
material respect any of Tenant's rights under this Lease, for example, and not
by way of limitation, changes to the Term, Fixed Rent, Additional Rent and
location of the Demised Premises.

                                   ARTICLE 10
                                 QUIET ENJOYMENT

            10.01. So long as Tenant pays all of the Rent and performs all of
Tenant's other obligations hereunder, Tenant shall peaceably and quietly have,
hold and enjoy the Demised premises without hindrance, ejection or molestation
by Landlord or any person lawfully claiming through or under Landlord, subject,
nevertheless, to the provisions of this Lease and to Superior Leases and
Mortgages.

                                       14
<PAGE>

                                   ARTICLE 11
                      ASSIGNMENT, SUBLETTING AND MORTGAGING

            11.01. Tenant shall not, whether voluntarily, involuntarily, or by
operation of law or otherwise, (a) assign or otherwise transfer this Lease or
offer or advertise to do so, (b) sublet the Demised Premises or any part
thereof, or offer or advertise to do so, or allow the same to be used, occupied
or utilized by anyone other than Tenant, or (c) mortgage, pledge, encumber or
otherwise hypothecate this Lease in any manner whatsoever, without in each
instance obtaining the prior written consent of Landlord, which consent shall
not be unreasonably withheld.

            11.02. Any proposed assignee, sublessee or transferee, whether or
not Landlord's consent is required hereunder, shall in any event:

                  (a)   demonstrate financial responsibility reasonably
                        necessary to fulfill its obligations hereunder; and

                  (b)   occupy the Demised Premises for the Permitted Use and
                        only the Permitted Use, as described in this Lease; and

                  (c)   in the reasonable opinion of Landlord, be a tenant whose
                        occupancy will be in keeping with the dignity and
                        character of a commercial building, including, without
                        limitation, telecommunications facilities, office,
                        retail and other lawful uses and the use and occupancy
                        of the Building and whose occupancy will not be more
                        objectionable or more hazardous than that of Tenant
                        herein or impose any additional burden upon Landlord in
                        the maintenance and operation of the Building and shall,
                        in the reasonable opinion of the Landlord, be eligible,
                        suitable and qualified as a tenant in the Building in
                        accordance with the provisions of this Lease.

            In connection with any proposed assignment, sublease or transfer,
Tenant shall pay to the Landlord on demand the reasonable costs (including
attorney's fees and costs) that may be incurred by the Landlord, including,
without limitation, the reasonable costs of making investigations as to the
acceptability of the proposed assignee or sublessee.

            11.03. An assignment of this Lease as to which Landlord's consent
shall be required shall be deemed to include: (i) if Tenant is a corporation not
listed on a recognized security exchange, one or more

                                       15
<PAGE>

sales or transfers of stock, by operation of law or otherwise, or creation of
new stock, by which an aggregate of more than 50% of Tenant's stock shall be
vested in a party or parties who are non-stockholders as of the date hereof
(except in the case of an Initial Public Offering issued through a nationally
recognized securities exchange); and (ii) if Tenant is a sole owner,
partnership, limited liability company or joint venture the transfer of any
interest in the Tenant, whether by sale, exchange, merger, consolidation or
otherwise.

            Subject to Section 11.02, Landlord shall grant its consent to
assignments of this Lease pursuant to transactions with a corporation into which
the Tenant may be merged or consolidated or to any corporation which shall be an
affiliate, subsidiary, parent or successor of Tenant, or of a corporation into
which or with which Tenant may be merged or consolidated, or to a partnership1
the majority interest in which shall be owned by stockholders of Tenant.

            For the purposes of this Article, a "subsidiary" or "affiliate" or
"successor" of Tenant shall mean the following:

            (a) an "affiliate" shall mean any corporation which, directly or
indirectly, controls or is controlled by or is under common control with Tenant.
For this purpose "control" shall mean the possession, directly or indirectly, of
the power to direct or cause the direction of the management and policies of
such corporation, whether through the ownership of voting securities or by
contract or otherwise;

            (b) a "subsidiary" shall mean any corporation, not less than 50% of
whose outstanding stock shall, at the time, be owned directly or indirectly by
Tenant; and

            (c) a "successor" of Tenant shall mean:

                  (i) a corporation in which or with which Tenant, its corporate
successors or assigns, is merged or consolidated, in accordance with applicable
statutory provisions for merger or consolidation of corporations, provided that
by operation of law or by effective provisions contained in the instruments of
merger or consolidation, the liabilities of the corporations participating in
such merger or consolidation are assumed by the corporation surviving such
merger or created by such consolidation, or

                  (ii) a corporation acquiring this Lease and the terms hereby
demised and a substantial portion of the property and assets of Tenant, its
corporate successors or assigns, or

                  (iii) a corporate successor to a successor corporation
becoming such either by the methods described in (i) or (ii) provided that in
the completion of such merger, consolidation, acquisition or assumption, the
successor shall have a net worth of no less than that of Tenant.

                                       16
<PAGE>

            11.04. If this Lease is assigned, whether or not in violation of
this Lease, Landlord may collect Rent from the assignee. If the Demised premises
or any part thereof are sublet or used or occupied by anybody other than Tenant,
whether or not in violation of this Lease, Landlord may, after default collect
Rent from the subtenant or occupant. In either event, Landlord may apply the net
amount collected to the Rent, but no such assignment, subletting, occupancy or
collection shall be deemed a waiver of any of the provisions of Section 11.01 or
Section 11.02, or the acceptance of the assignee, subtenant or occupant as
tenant, or a release of Tenant from the performance by Tenant of Tenant's
obligations under this Lease. The consent by Landlord to any assignment,
mortgaging, subletting or use or occupancy by others shall not in any way be
considered to relieve Tenant from obtaining the express written consent of
Landlord to any other or further assignment, mortgaging or subletting or use or
occupancy by others not expressly permitted by this Article 11. References in
this Lease to use or occupancy by others (that is, anyone other than Tenant)
shall not be construed as limited to subtenants and those claiming under or
through subtenants but shall be construed as including also licensees and others
claiming under or through Tenant, immediately or remotely.

            11.05. Any permitted assignment or transfer, whether made with
Landlord's consent or without Landlord's consent, shall be made only if, and
shall not be effective until, the assignee or transferee shall execute,
acknowledge and deliver to Landlord an agreement in form and substance
satisfactory to Landlord whereby the assignee or transferee shall assume
Tenant's obligations under this Lease from and after the effective date of the
assignment or transfer and whereby the assignee or transferee shall agree that
all of the provisions in this Article 11 shall, notwithstanding such assignment
or transfer, continue to be binding upon it in respect to all future assignments
and transfers. notwithstanding any assignment or transfer, whether or not in
violation of the provisions of this Lease, and notwithstanding the acceptance of
Rent by Landlord from an assignee, transferee, or any other party, the original
Tenant and any other person(s) who at any time was or were Tenant shall remain
fully liable for the payment of the Rent and for Tenant's other obligations
under this Lease.

            11.06. The liability of the originally named Tenant and any other
Person(s) who at any time was or were Tenant for Tenant's obligations under this
Lease shall not be discharged, released or impaired by any agreement or
stipulation made by Landlord extending the time of, or modifying any of the
obligations of, this Lease, or by any waiver or failure of Landlord to enforce
any of the obligations of this Lease.

            11.07. The listing of any name other than that of Tenant, whether on
the doors of the Demised Premises or the Building directory, or otherwise, shall
not operate to vest any right or interest in this Lease or in the Demised
Premises, nor shall it be deemed to be the consent of Landlord to any assignment
or transfer of this Lease or to any sublease of the Demised Premises or to the
use or occupancy thereof by others.

                                       17
<PAGE>

            11.08. In the event of any assignment or sublease of the Demised
Premises which requires the payment of Fixed Rent, Additional Rent and other
charges in excess of the amounts payable to the Landlord as set forth in this
Lease, then the "net excess or profit" shall be divided and paid equally to
Landlord and Tenant. In the event the Tenant fails to make payment of such
excess or profit in violation of this Lease, Landlord may collect such rent
directly from the assignee or subtenant. The "net excess or profit" shall mean
the amount remaining after payment of Fixed Rent, Additional Rent and other
standard, customary, and reasonable charges, marketing, brokerage and other
professional fees and expenses reasonably incurred by Tenant.

                                   ARTICLE 12
                              COMPLIANCE WITH LAWS

            12.01. Tenant shall comply with all Legal Requirements which shall,
in respect of the Demised Premises or the use and occupation thereof, or the
abatement of any nuisance in, on or about the Demised Premises, impose any
violation, order or duty on Landlord or Tenant; and Tenant shall pay all the
cost, expenses, fines, penalties and damages which may be imposed upon Landlord
or any Superior Lessor by reason of or arising out of Tenant's failure to fully
and promptly comply with and observe the provisions of this Section 12.01.
However, Tenant need not comply with such law or requirement of any public
authority so long as Tenant shall be contesting the validity thereof, or the
applicability thereof to the Demised Premises, in accordance with Section 12.02.

            12.02. Tenant may contest by appropriate proceedings prosecuted
diligently and in good faith, the validity, or applicability to the Demised
Premises, of any Legal Requirement, provided that (a) Landlord shall not be
subject to criminal penalty or to prosecution for a crime, and neither the
Demised Premises nor any part thereof shall be subject to being condemned or
vacated by reason of non-compliance or otherwise by reason of such contest; (b)
before the commencement of such contest, Tenant shall furnish to Landlord either
(i) the bond of a surety company satisfactory to Landlord, which bond shall be,
as to its provisions and form, satisfactory to Landlord and shall be in an
amount at least equal to 125% of the cost of such compliance (as estimated by a
reputable contractor designated by Landlord) and shall indemnify Landlord
against the cost thereof and against all liability for damages, interest,
penalties and expenses (including reasonable attorney's fees and expenses),
resulting from or incurred in connection with such contest or non-compliance,
or (ii) other security in place of such bond satisfactory to Landlord; (c) such
non-compliance or contest shall not constitute or result in any violation of
any Superior Lease or Superior Mortgage, or if any such Superior Lease and/or
Superior Mortgage shall permit such non-compliance or contest on condition of
the taking of action or furnishing of security by Landlord, such action shall be
taken and such security shall be furnished at the expense of Tenant; and (d)
Tenant shall keep Landlord advised as to the status of such proceedings. Without
limiting the application of the above, Landlord shall be deemed subject to
prosecution for a crime if Landlord, or its managing agent,

                                       18
<PAGE>

or any officer, director, partner, shareholder or employee of Landlord or its
managing agent, as an individual, is charged with a crime of any kind or degree
whatsoever, whether by service of summons or otherwise, unless such charge is
withdrawn before Landlord or its managing agent, or such officer, director,
partner, shareholder or employee of Landlord or its managing agent (as the case
may be) is required to plead or answer thereto.

            12.03. Landlord shall comply with all then existing Legal
Requirements and shall pay all the cost, expenses, fines, penalties and damages
which may be imposed upon Tenant for any violation by Landlord of the Legal
Requirements existing at the time of the completion of Tenant's Initial
Improvements. Landlord shall comply with all Legal Requirements applicable to
the Building (other than the Demised Premises) during the Term.

                                   ARTICLE 13
                             INSURANCE AND INDEMNITY

            13.01. Landlord shall maintain or cause to be maintained All-Risk
insurance in respect of the Building and other improvements on the Land normally
covered by such insurance (except for the property Tenant is required to cover
with insurance under Section 13.02 and similar property of other tenants and
occupants of the Building and except for buildings and other improvements which
are on land neither owned by nor leased to Landlord) for the benefit of
Landlord, any Superior Lessors, any Superior Mortgagees and any other parties
Landlord may at any time and from time to time designate, as their interests may
appear, but not for the benefit of Tenant, and shall maintain rent insurance as
required by any Superior Lessor or any Superior Mortgagee. The All-Risk
insurance will be in the amounts required by the Superior Lessor or any Superior
Mortgagee but not less than the amount sufficient to avoid the effect of the
coinsurance provisions of the applicable policy or policies. Landlord may also
maintain any other forms and types of insurance which Landlord shall deem
reasonable in respect to the Building and Land. Landlord shall have the right to
provide any insurance maintained or caused to be maintained by it under blanket
policies.

            13.02. Tenant shall maintain the following insurance: (a)
comprehensive general public liability insurance in respect of the Demised
Premises and the conduct and operation of business therein, with limits of not
less than $6,000,000 for bodily injury or death and $3,000,000 for property
damage, including water damage, sprinkler leakage legal liability, independent
contractors, premises operation, products and completed operations, (b)
All-Risk insurance in respect to Tenant's stock in trade, fixtures, furniture,
furnishings, removable floor coverings, equipment, signs, and all other property
of Tenant in the Demised Premises, in any amounts required by any Superior
Lessor or any Superior Mortgagee but not less than 90% of the full insurable
value of the property covered and not less than the amount sufficient to avoid
the effect of the coinsurance provisions of the applicable policy or

                                       19
<PAGE>

policies; (c) workers' compensation insurance; (d) rental insurance in an amount
equal to not less than one (1) year's Fixed Rent and Additional Rent, which
shall be automatically renewable annually; (e) Business Loss insurance and (f)
any other insurance required for compliance with the Insurance Requirements.
Landlord, any manager of the Building and any Superior Lessors or Superior
Mortgagees shall be named as insureds in all said policies of insurance and
shall be protected against all liability occasioned by an occurrence insured
against. All such policies of insurance shall be: (i) written as "occurrence"
policies; (ii) written as primary policy coverage and not contributing with or
in excess of any coverage which Landlord or any Superior Mortgagee or Superior
Lessor may carry; and (iii) issued by insurance company reasonably satisfactory
to Landlord. Tenant shall deliver to Landlord and any other insured(s)
certificates for such fully paid-for policies at least ten (10) days before the
Commencement Date. Tenant shall procure and pay for renewals of such insurance
from time to time before the expiration thereof, and Tenant shall deliver to
Landlord and any other insured(s) certificates therefor at least thirty (30)
days before the expiration of any existing policy. All such policies shall be
issued by companies of recognized responsibility licensed to do business in the
State of Washington and all such policies shall contain a provision whereby the
insurer shall provide written notice to Landlord and any additional insured(s)
at least twenty (20) days prior to cancellation or modification of such
policies.

            13.03. Tenant shall not do, permit or suffer to be done any act,
matter, thing or failure to act in respect of the Demised Premises or use or
occupy the Demised Premises or conduct or operate Tenant's business in `any
manner objectionable to any insurance company or companies whereby the fire
insurance or any other insurance then in effect in respect to the Land and
Building or any part thereof shall become void or suspended or whereby any
premiums in respect of insurance maintained by Landlord shall be higher than
those which would normally have been in effect for the occupancy contemplated
under the Permitted Use. Landlord shall give Tenant written notice in the event
Landlord becomes aware of Tenant's breach of the provisions of this Section
13.03. In case of a breach of the provisions of this Section 13.03, in addition
to all other rights and remedies of Landlord hereunder, Tenant shall (a)
indemnify Landlord, Superior Lessors and the Superior Mortgagees, and hold
Landlord, Superior Lessors and Superior Mortgagees harmless from and against any
loss which would have been covered by insurance which shall have become void or
suspended because of such breach by Tenant and (b) pay to Landlord any and all
increases of premiums on any insurance, including, without limitation, rent
insurance1 resulting from any such breach.

            13.04. Subject to Section 13.03 and to the extent not covered by
Tenant's insurance, Tenant shall indemnify, defend and hold harmless Landlord,
Superior Mortgagee and all Superior Lessors and their respective partners, joint
venturers, directors, officers, agents, servants and employees from and against
any and all claims arising from or in connection with (a) the conduct or
management of the Demised Premises or of any business therein or any work or
thing whatsoever

                                       20
<PAGE>

done, or any condition created (other than by Landlord) in the Demised Premises
during the Term or during the period of time, if any, prior to the Commencement
Date that Tenant may have been given access to the Demised Premises, caused by
Tenant, or any of its subtenants or licensees or its or their partners, joint
venturers, directors, officers, agents employees representatives or contractors:
(b) any act, omission or negligence of Tenant or any of its subtenants or
licensees or its or their partners, joint venturers, directors, officers,
agents, employees or contractors: (c) any accident, injury or damage whatever
(unless and to the extent caused by Landlord's negligence) occurring in the
Demised Premises, caused by Tenant, or any of its subtenants or licensees or its
or their partners, joint venturers, directors, officers agents, employees or
contractors; and (d) any breach or default by Tenant in the full and prompt
payment and performance of Tenant's obligations under this Lease. Tenant's
obligation to indemnify shall also include all costs, expenses and liabilities
incurred in or in connection with each such claim or action or proceeding
brought thereon, including without limitation, all attorney's fees, expert fees
and expenses. In case any action or proceeding is brought against Landlord,
Superior Mortgagee and/or any Superior Lessor and/or its or their partners,
joint venturers, directors, officers, agents and/or employees by reason of such
claim, Tenant upon notice from Landlord, Superior Mortgagee and/or such Superior
Lessor, shall resist and defend such action or proceeding by counsel reasonably
satisfactory to Landlord.

            13.05. Landlord, Superior Mortgagee or any Superior Lessor, shall
not be liable to or responsible for, and Tenant hereby releases Landlord,
Superior Mortgagee and Superior Lessor from all liability and responsibility to
Tenant and any person claiming by, through or under Tenant, by way of
subrogation, for any injury, loss or damage to any person or property in the
Demised Premises or to Tenant's business irrespective of the cause of such
injury, loss or damage. This release shall apply to the extent that such injury,
loss or damage to person or property is covered and actually paid by insurance,
regardless of whether such insurance is payable to or protects Landlord, Tenant
or both. Nothing herein shall be construed to impose any other or greater
liability upon Landlord than would have existed in the absence of this
provision. Further, Tenant shall require its insurers to include in all of
Tenant's insurance policies which could give rise to a right of subrogation
against Landlord, Superior Mortgagee and Superior Lessor a clause or endorsement
whereby the insurer waives any rights of subrogation against Landlord, Superior
Mortgagee and such Superior Lessor or permits the insured, prior to any loss, to
agree with a third party to waive any claim it may have against said third party
without invalidating the coverage under the insurance policy. The release in
favor of Landlord, Superior Mortgagee and Superior Lessors, contained herein, is
in addition to, and not in substitution for, or in diminution of the hold
harmless and indemnification provisions contained in this Article and in Article
23.

            13.06. Except as provided herein, Tenant shall not be liable or
responsible for and Landlord hereby releases Tenant from all liability and
responsibility to Landlord and any person claiming by,

                                       21
<PAGE>

through or under Landlord by way of subrogation for any injury, loss or damage
to any person or property in the Demised Premises irrespective of the cause of
such injury, loss or damage. This release shall apply to the extent that such
injury, loss or damage to person or property is covered by insurance, regardless
of whether such insurance is payable to or protects Landlord, Tenant or both.
Nothing herein shall be construed to impose any other or greater liability upon
Tenant than would have existed in the absence of this provision. Further,
Landlord shall require its insurers to include in all of Landlord's insurance
policies which could give rise to a right of subrogation against Tenant, a
clause or endorsement whereby the insurer waives any right of subrogation
against Tenant or permits the insured, prior to any loss, to agree with a third
party to waive any claim against said third party without invalidating the
coverage under the insurance policy.

                                   ARTICLE 14
                              RULES AND REGULATIONS

            14.01. Tenant and its employees and agents shall faithfully observe
and comply with the Rules and Regulations (attached hereto as Exhibit C) and
such reasonable changes therein (whether by modification, elimination or
addition) as Landlord at any time or times hereafter may make and communicate to
Tenant, which, in Landlord's reasonable judgment, shall be desirable or
necessary for the reputation, safety, care or appearance of the Land and
Building, or the preservation of good order therein or the operation or
maintenance of the Building or its equipment and fixtures, or the Common Areas,
and which do not unreasonably affect the conduct of Tenant's business in the
Demised Premises; provided, however, that in case of any conflict or
inconsistency between the provisions of this Lease and any of the Rules and
Regulations, the provisions of this Lease shall control. Nothing contained in
this Lease shall be construed to impose upon Landlord any duty or obligation to
enforce the Rules and Regulations against any other tenant or any employees or
agents of any other tenant, and Landlord shall not be liable to Tenant for
violation of the Rules and Regulations by any other tenant or its employees,
agents, invitees or licensees. Landlord shall give Tenant notice of any change
in the Rules and Regulations. Landlord shall not enforce the Rules and
Regulations against Tenant in an arbitrary or discriminatory manner. Tenant
shall further comply with any rules, regulations, instructions or directions
posted in, on or about the Building.

                                   ARTICLE 15
                                   ALTERATIONS

            15.01. Except with respect to Tenant's Initial Improvements, Tenant
shall not make any alterations or additions to the Demised Premises, or make any
holes or cuts in the walls, ceilings, roofs or floors thereof, or change the
architectural treatment of the Demised Premises without the Landlord's prior
written consent, which consent shall not be unreasonably withheld. Tenant shall
submit to Landlord plans and specifications for such work at the time notice is
given to

                                       22
<PAGE>

Landlord or at any time requested by Landlord, which plans and specifications
shall be subject to Landlord's prior written approval which shall not be
unreasonably withheld. Before proceeding with any alterations, Tenant shall
fully and promptly comply with and observe the Rules and Regulations then in
force in respect of the making of alterations. Any review or approval by
Landlord of any plans and/or specifications with respect to any alterations is
solely for Landlord's benefit, and without any representation or warranty
whatsoever to Tenant in respect to the adequacy, correctness or efficiency
thereof or otherwise. Tenant shall pay Landlord the actual cost of any
architectural, engineering, legal or other review of any alterations or
additions to the Demised Premises.

            15.02. Tenant shall obtain all necessary governmental permits and
certificates for the commencement and prosecution of permitted alterations and
for final approval thereof upon completion, and shall cause alterations to be
performed in compliance with all applicable Legal Requirements and Insurance
Requirements. Alterations shall be diligently performed in a good and
workmanlike manner, using new materials and equipment at least equal in quality
and class to the original installations of the Building. Alterations shall be
performed by Contractors subject to Landlord's reasonable approval. Alterations
shall be made in such manner as not to unreasonably interfere with or delay and
as not to impose any additional expense upon Landlord in the construction,
maintenance, repair, rental or operation of the Building; and if any such
additional expense shall be incurred by Landlord as a result of Tenant's making
of any alterations, Tenant shall pay any such additional expense upon demand.
Throughout the making of alterations, Tenant shall carry, or cause to be
carried, workmen's compensation insurance in statutory limits, a full payment
and performance bond in favor of Landlord and general liability insurance, with
completed operation endorsement, for any occurrence in or about the Building,
under which Landlord and its managing agent and any Superior Lessor whose name
and address shall previously have been furnished to Tenant shall be named as
parties insured, in such limits as Landlord may reasonably require, with
insurers reasonably satisfactory to Landlord. Tenant shall furnish Landlord with
reasonably satisfactory evidence that such insurance is in effect at or before
the commencement of alterations and on request at reasonable intervals
thereafter during the making of alterations.

                                   ARTICLE 16
                        LANDLORD'S AND TENANT'S PROPERTY

            16.01. All fixtures, equipment, improvements and appurtenances
attached to or built into the Demised Premises at the commencement of or during
the Term, whether or not by or at the expense of Tenant, shall be and remain a
part of the Demised Premises, shall be deemed to be the property of Landlord and
shall not be removed by Tenant, except as provided in Section 16.02. Further,
any carpeting or

                                       23
<PAGE>

other personal property in the Demised Premises on the Commencement Date, unless
installed and paid for by Tenant, shall be and shall remain Landlord's property
and shall not be removed by Tenant. Notwithstanding the foregoing, any switch
equipment owned or leased by Tenant for use at the Demised Premises shall remain
Tenant's Property.

            16.02. All movable partitions, business and trade fixtures,
machinery and equipment, communications equipment and office equipment, whether
or not attached to or built into the Demised Premises, which are installed in
the Demised Premises or the Building by or for the account of Tenant without
expense to Landlord and can be removed without structural damage to the Building
and all furniture, furnishings, and other movable personal property owned by
Tenant and located in the Demised premises (collectively, "Tenant's Property")
shall be and shall remain the property of the Tenant and may be removed by
Tenant at any time during the Term, provided that if any of the Tenant's
Property is removed, Tenant shall repair or pay the cost of repairing any damage
to the Demised Premises, the Building or the exterior Common Areas, resulting
from the installation and/or removal thereof. Any equipment or other property
for which Landlord shall have granted any allowance or credit to Tenant shall
not be deemed to have been installed by or for the account of Tenant without
expense to Landlord, shall not be considered as the Tenant's Property and shall
be deemed the property of Landlord.

            16.03. In the event at or before the Expiration Date or the date of
any earlier termination of this Lease, or within thirty (30) days after the
Expiration Date or an earlier termination date, Tenant removes from the Demised
Premises all of the Tenant's Property (except such items thereof as Landlord
shall have expressly permitted to remain, which property shall become the
property of the Landlord if not removed), Tenant shall repair any damage to the
Demised Premises, the Building and the Common Areas resulting from any
installation and/or removal of the Tenant's Property. Any items of the Tenant's
Property which shall remain in the Demised Premises after the Expiration Date or
after a period of thirty (30) days following the Expiration Date or an earlier
termination date, may, at the option of the Landlord, be deemed to have been
abandoned, and in such case such items may be retained by Landlord as its
property or disposed of by Landlord, without accountability, in such manner as
Landlord shall determine at Tenant's expense.

                                   ARTICLE 17
                        REPAIRS, MAINTENANCE AND CLEANING

            17.01. Tenant shall, throughout the Term, take good care of the
Demised Premises, the fixtures, the equipment and appurtenances therein and any
and all equipment outside of the Demised Premises installed by Tenant. Tenant,
at its expense, shall be responsible for all repairs, interior and exterior,
structural and non-structural, ordinary and extraordinary, in and to the
Demised Premises, the premises of other tenants, the Building (including the
facilities and systems

                                       24
<PAGE>

thereof), and the Common Areas the need for which arises out of (a) the
performance of alterations, (b) the installation, use or operation of the
Tenant's Property in the Demised Premises, (c) the moving of the Tenants
Property in or out of the Building, or (d) the act, omission, misuse or neglect
of Tenant or any of its subtenants or its or their employees, agents,
contractors or invitees. Tenant shall promptly replace all scratched, damaged or
broken doors and glass in and about the Demised Premises and shall be
responsible for all repairs, maintenance and replacement of wall and floor
coverings in the Demised Premises and for the repair and maintenance of all
sanitary and electrical fixtures and equipment therein. Tenant shall promptly
make all repairs in or to the Demised Premises for which Tenant is responsible.
Any repairs required to be made by Tenant to the mechanical, electrical,
sanitary, heating, ventilating, air-conditioning or other systems of the
Building within the Demised Premises shall be performed only by contractor(s)
designated by Landlord in its sole reasonable discretion. Any other repairs in
or to the Building, its facilities and Systems or the premises of other tenants
for which Tenant is responsible shall be performed by Landlord at Tenant's
expense; but Landlord may, at its option, before commencing any such work or at
any time thereafter, require Tenant to furnish to Landlord such security, in
form (including, without limitation, a bond issued by a corporate surety
licensed to do business in Washington) and amount, as Landlord shall deem
necessary to assure the payment for such work by Tenant. In the event that
Tenant's use or operation of any equipment installed either within the Demised
Premises or outside the Demised Premises for Tenant's use violates any
governmental law, rule, regulation or mandate, Tenant shall be fully
responsible, at its own cost and expense, for bringing the premises into
compliance with such governmental laws, rules, regulations or mandates.

            17.02. Landlord shall be responsible for all repairs and maintenance
in and to the Building (including the facilities and systems and structure
thereof), except for those repairs and maintenance for which Tenant is
responsible pursuant to any of the provisions of this Lease and except for any
building systems installed by Tenant for Tenant's exclusive use. Tenant shall
give Landlord written notice of any repairs it believes Landlord should make. In
the event Landlord has not commenced making the repairs within ten (10) Business
Days subsequent to Landlord's receipt of this notice, Tenant may elect to give
Landlord written notice of Tenant's intention to do the repair. In the event
Landlord has not commenced the repair within ten (10) Business Days of
Landlord's receipt of such written notice, Tenant may do the repair and Landlord
shall reimburse Tenant for all reasonable costs in connection therewith. The
foregoing notwithstanding, Tenant shall at no time and in no event be entitled
to make, or cause to be made, any repairs or replacements to, or provide
maintenance for, the electrical (including, without limitation, electrical
generator systems), the heating, ventilating and air-conditioning systems in
the Building, or any conduits, cables, wiring or piping in the vertical risers
or other locations in the Building.

                                       25
<PAGE>

            17.03. Except as otherwise expressly provided in this Lease,
Landlord shall have no liability to Tenant, nor shall Tenant's covenants and
obligations under this Lease be reduced or abated in any manner whatsoever, by
reason of any inconvenience, annoyance, interruption or injury to business
arising from Landlord's doing any repairs, maintenance, or changes which
Landlord is required or permitted by this Lease, or required by law, to make in
or to any portion of the Building.

            17.04 Landlord, at its cost and expense (but includable in Operating
Expenses), shall be responsible for furnishing cleaning services for the Common
Areas of the Building. Tenant, at is cost and expense, shall be responsible for
furnishing cleaning services for the Demised Premises. Tenant shall be
responsible for the disposal and removal of all of its garbage and waste at the
Demised Premises on a periodic basic (but not less than on three (3) occasions
per week) and shall utilize a waste or garbage contractor for such purpose
reasonably satisfactory to Landlord.

                                   ARTICLE 18
                                 ELECTRIC ENERGY

            18.01. Landlord shall provide reasonably sufficient leads at an
electrical vault, located in the first floor of the Building for 800 amps at 480
volts electrical service dedicated to the Demised Premises. Tenant, at its sole
cost and expense, shall provide and install an electrical meter in order to
measure electrical usage by Tenant at the Demised Premises together with a
switch and bus duct to the Demised Premises. Prior to the installation of such
electrical service, Tenant shall have access to up to 400 amps at 480 volts of
electrical services and shall be at Tenant's sole cost and expense.

            18.02. Landlord shall have the right at any time and from time to
time during the Term if permitted by the Legal Requirements, to contract for
service from a company or companies ("Electric Service Provider") different from
the company providing electrical service to the Building and the Demised
Premises as of the date of this Lease.

            18.03. Landlord shall have full and unrestricted access to all
air-conditioning and heating equipment, and to all other utility installations
servicing the Building and the Demised Premises. Further, Tenant shall cooperate
with Landlord and the Electric Service Provider at all times and, as reasonably
necessary, shall allow Landlord and Electric Service Provider reasonable access
to the Building's electrical lines, feeders, risers, conduits, wiring and any
other machinery within the Demised Premises. Landlord reserves the right
temporarily to reasonably interrupt, curtail, stop or suspend electrical,
air-conditioning, heating service, and all other utility, or other services,
because of Landlord's inability to obtain, or difficulty or delay in obtaining,
labor or materials necessary therefor, or in order to comply with governmental
restrictions in connection therewith, or in order for the Landlord to perform
any preventive maintenance in connection with the Building or any Building
system, or to change the

                                       26
<PAGE>

Electric Service Provider for the Building for any cause beyond Landlord's
reasonable control. No diminution or abatement of Fixed Rent, Additional Rent,
or other compensation shall be or will be claimed by Tenant, nor shall this
Lease or any of the obligations of Tenant hereunder be affected or reduced by
reason of such interruptions, stoppages or curtailments, the causes of which are
hereinabove enumerated, nor shall the same give rise to a claim in Tenant's
favor that such failure constitutes actual or constructive, total or partial
eviction from the Demised Premises, unless such interruptions, stoppages or
curtailments have been due to the intentional or willful misconduct of Landlord.

            18.04. Landlord shall not be liable or responsible to Tenant in any
way for any loss, damage or expense which Tenant may sustain or incur as a
result of any (i) interruption, curtailment or failure (whether or not
temporary) or (ii) defect in the supply, character, quantity, availability or
suitability of electricity (including generator power) furnished to the Demised
Premises by reason of any requirement, act or omission of the Electric Service
provider or any other company servicing the Building with electricity or for the
performance of any maintenance or repair required hereunder or for any other
reason except if and to the extent the same is caused by or results from the
intentional or willful misconduct of Landlord.

            18.05. If either the quantity or character of electrical service is
changed by the Electric Service Provider or other company supplying electricity
to the Building or is no longer available or suitable for Tenant's requirements,
no such change, unavailability or unsuitability shall constitute an actual or
constructive eviction, in whole or in part, or entitle Tenant to any abatement
or diminution in the payment of Fixed Rent, or relieve Tenant from any of its
obligations under this Lease, or impose any liability upon Landlord, or its
agents, by reason of inconvenience or annoyance to Tenant, or injury to or
interruption of Tenant's business, or otherwise.

            18.06. Tenant shall pay, as and for Additional Rent, all charges
imposed by the Electric Service Provider servicing the Demised Premises and the
Building promptly when due based upon a submeter installed by Tenant at its sole
cost and expense. In the event that the Electric Service Provider servicing the
Demised Premises directly charges Tenant, Tenant shall make payment of such
charges promptly when due and shall pay all late payments, interest and other
charges should Tenant be delinquent in its payment to the Electric Service
Provider. In the event that Tenant does not pay the Additional Rent owing by
Tenant or pay the Electric Service Provider pursuant to this Article within ten
(10) Business Days after the request for same by Landlord, Landlord may, without
further notice and in addition to any other remedies Landlord may have,
discontinue the service of electricity to the Demised Premises without releasing
Tenant from any liability under this Lease and without Landlord incurring any
liability for any damage or loss sustained by Tenant as the result of such
discontinuance. If any tax is imposed upon Landlord's receipts from the sale or
resale of electric current to Tenant by any Federal, state or municipal
authority,

                                       27
<PAGE>

Tenant agrees that, unless prohibited by law, Tenant's proportionate share of
such tax shall be passed on to, and included in the bill of, and paid by Tenant
to Landlord as Additional Rent. Tenant hereby agrees to indemnify, defend and
hold Landlord harmless from and against any claims, damages, lawsuits,
penalties, interest or other charges imposed by the Electric Service Provider as
a result of electrical energy utilized by the Tenant and directly charged to
Tenant by the Electric Service Provider.

            18.07. Except as otherwise provided, Tenant will make no electrical
installations, alterations, additions or changes to electrical equipment or
appliances without the prior written consent of Landlord in each instance which
consent shall not be unreasonably withheld or delayed. Tenant will at all times
comply with the rules, regulations, terms and conditions applicable to service,
equipment, wiring and requirements of the Electric Service Provider supplying
electricity to the Building. Tenant covenants and agrees that at all times its
use of electric current will not exceed the capacity of existing feeders to the
Building or the risers or wiring installation and Tenant will not use any
electrical equipment which, in Landlord's reasonable judgment, will overload
such installations or interfere with the use thereof by other tenants of the
Building. In the event that, in Landlord's reasonable judgment, Tenant's
electrical requirements necessitate installation of an additional riser, risers
or other proper and necessary equipment, the same shall be installed by Landlord
at Tenant's sole expense and shall be chargeable and collectible as Additional
Rent and paid within ten (10) days after the rendition of a bill to Tenant
therefor.

            18.08 Tenant, at Tenant's sole cost and expense, shall be permitted
to connect to Landlord's generators and fuel tank system at a cost of $750 per
amp of capacity, plus a pro rata share of the actual cost to maintain and
operate the generators. Tenant will be required to separate their panel and
install shunt trip breakers in order to shed any non-backed-up power. Tenant
shall be allowed, at its sole cost and expense, to install a plug for a roll-up
generator subject to all governmental codes, rules and regulations and subject
further to Landlord's prior written approval thereof.

                                   ARTICLE 19
                     HEAT, VENTILATION AND AIR-CONDITIONING

            19.01. Landlord shall maintain and operate the Building's heating,
ventilating and air-conditioning systems (hereinafter called the "Systems"),
and shall furnish heat, ventilating and air-conditioning (hereinafter
collectively called "HVAC services"), in the Demised Premises through the
Systems. Tenant shall pay as and for Additional Rent for the HVAC Services the
sum of $750 per ton for 60 tons, plus a pro rata share of the actual costs to
maintain and operate the Systems. Tenant shall have the use of up to 50 tons of
existing building water

                                       28
<PAGE>

prior to the upgrade of the Systems. The cost to distribute and the cost of
actual use shall be at Tenant's sole cost and expense.

            19.02. Landlord shall furnish necessary elevator service during
Business Hours and shall have an elevator subject to call at all other times.
Further, Landlord shall make available to Tenant a crane for the installation of
equipment in the Demised Premise or to perform Tenant's Initial Improvements. If
Landlord shall at any time have elected to furnish operator service for any
automatic elevators, Landlord shall have the right to discontinue furnishing
such service. If Tenant shall require the use of the Building's elevators or
crane, Tenant shall be responsible for and shall pay Landlord's costs and
expenses for the use thereof, as an Additional Rent, within ten (10) Business
Days after demand, including without limitation, any expense for operator
service for such elevator or crate which Landlord may deem necessary in
connection with Tenant's use of such elevator or crane. Landlord shall have the
right to change the operation or manner of operating any of the elevators in the
Building and shall have the right to discontinue, temporarily or permanently,
the use of any one or more cars in any of the banks of elevators.

                                   ARTICLE 20
                             BROADCAST INTERFERENCE

            20.01. Interference: As used in this Lease, "interference" with
broadcasting activity means:

            (a) interference within the meaning of the provisions of the
recommended practices of the Electronics Industries Association and the rules
and regulations of the Federal Communications Commission ("FCC") as in effect
from time to time, or

            (b) a material impairment of the quality of either sound or picture
signals on a broadcasting activity as may be defined by the FCC at any hour
during the period of operation of the activity, as compared with that which
would be obtained if no other broadcaster were broadcasting from the Building or
had any equipment on the building or in the Demised Premises.

            Tenant shall take reasonable, prompt and diligent actions to prevent
and shall promptly remove or cause to be removed any interference with broadcast
activities of Landlord, other tenants of Landlord, or other occupants of the
Building caused by Tenant's use of the Demised Premises.

                                   ARTICLE 21
                            ACCESS, CHANGES AND NAME

            21.01. Except for the space within the inside surfaces of all
outside walls, ceilings, floors, windows and doors bounding the Demised
Premises, all of the Building, including, without limitation, exterior Building
walls, core corridor walls and doors and any core

                                       29
<PAGE>

corridor entrance, and any space in or adjacent to the Demised Premises used for
shafts, risers, chaseways, stacks, pipes, conduits, fan rooms, ducts, electric
or other utilities, sinks or other Building facilities and the use thereof, as
well as access thereto in, on or through the Demised Premises for the purpose of
operating, maintenance, decoration and repair, are reserved to Landlord.
Landlord also reserves the right to install, erect, use and maintain pipes,
ducts and conduits in, on or through the Demised Premises, provided such are
properly enclosed.

            21.02. Landlord and its agents shall have the right to enter and/or
pass through the Demised Premises at any time or times (a) to examine the
Demised Premises and to show them to actual and prospective Superior Lessors,
Superior Mortgagees, or prospective purchasers of the Building, and (b) to make
such repairs, alterations, additions and improvements in or to the Demised
premises and/or in or to the Building or its facilities and equipment as
Landlord is required or desires to make. Reasonable access upon ten (10) days
prior written notice shall also be provided to other tenants or occupants in the
Building for any repair or maintenance of risers or conduits in the Demised
Premises. Landlord shall be allowed to take all materials into and upon the
Demised Premises that may be required in connection therewith, without any
liability to Tenant and without any reduction of Tenant's obligations hereunder.
During the period of eighteen (18) months prior to the Expiration Date or the
date when Tenant has given Landlord notice of Tenant's intention to terminate
this Lease pursuant to the provisions herein, Landlord and its agents may
exhibit the Demised Premises to prospective tenants. Landlord shall give notice
to the Tenant reasonable under the circumstances and make reasonable efforts to
avoid a material adverse impact on the conduct of Tenant's business.

            21.03 Tenant shall have access to the elevator lobby of the Building
and the Demised Premises twenty-four (24) hours per day, seven (7) days per
week throughout the Calendar Year.

            21.04. If, during the last month of the Term, Tenant has removed all
or substantially all of the Tenant's Property from the Demised Premises,
Landlord may, without notice to Tenant, immediately enter the Demised Premises
and later, renovate and decorate the same, without liability to Tenant and
without reducing or otherwise affecting Tenant's obligations hereunder.

            21.05. Landlord reserves the right, at any time and from time to
time, to make such changes, alterations, additions and improvements in or to the
Building and the fixtures and equipment thereof as Landlord shall deem necessary
or desirable, provided however, Landlord shall not cause a material adverse
impact on the conduct of Tenant's business, nor shall Landlord do anything
inconsistent with maintaining the Building as a commercial building, including,
without limitation, telecommunications facilities, office, retail and other
lawful uses.

                                       30
<PAGE>

                                   ARTICLE 22
                        MECHANICS' LIENS AND OTHER LIENS

             22.01. Nothing contained in this Lease shall be deemed, construed
or interpreted to imply any consent or agreement on the part of Landlord to
subject Landlord's interest or estate to any liability under any mechanic's or
other lien law. If any mechanic's or other lien or any notice of intention to
file a lien is filed against the Land, or any part thereof, or the Demised
premises, or any part thereof, for any work, labor, service or materials claimed
to have been performed or furnished for or on behalf of Tenant or anyone holding
any part of the Demised Premises through or under Tenant, Tenant shall cause the
same to be canceled and discharged of record by payment, bond or order of a
Court of competent jurisdiction within fifteen (15) days after notice by
Landlord to Tenant.

             23.01. None of Landlord, Superior Mortgagee, Superior Lessor, their
respective partners, joint venturers, directors, officers, agents, servants or
employees shall be liable to Tenant for any loss, injury or damage to Tenant or
to any other Person, or to its or their property, irrespective of the cause of
such injury, damage or loss, unless caused by or resulting from the intentional
or willful misconduct of Landlord, its agents, servants or employees in the
operation or maintenance of the Land or Building to the extent caused by such
intentional or willful misconduct. Further, Landlord, Superior Mortgagee,
Superior Lessor or their respective partners, joint venturers, directors,
officers, agents, servants or employees shall not be liable to Tenant (a) for
any such damage caused by other tenants or Persons in, upon or about the Land or
Building, or caused by operations in construction of any private work, performed
by someone other than Landlord or its employees, agents or contractors, or by
public or quasi-public work; or (b) even in the event of intentional or willful
misconduct, for consequential damages arising out of any loss of use of the
Demised Premises or any equipment or facilities therein by Tenant or any Person
claiming through, against or under Tenant.

             23.02. Notwithstanding any provision to the contrary, Tenant shall
look solely to the estate and property of Landlord in and to the Land and
Building (or the proceeds received by Landlord on a sale of such estate and
property but not the proceeds of any financing or refinancing thereof) in the
event of any claim against Landlord arising out of or in connection with this
Lease, the relationship of Landlord and Tenant or Tenant's use of the Demised
Premises or the Common Areas, and Tenant agrees that the liability of the
Landlord arising out of or in connection with this Lease, the relationship of
Landlord and Tenant or Tenant's use of the Demised Premises or the Common Areas
shall be limited to such estate and property of Landlord (or sale proceeds). No
other properties or assets of Landlord or any partner, joint venturer, director,
officer, agent, servant or employee of Landlord shall be

                                       31
<PAGE>

subject to levy, execution or other enforcement procedures for the satisfaction
of any judgment (or other judicial process) or for the satisfaction of any other
remedy of Tenant arising out of, or in connection with, this Lease, the
relationship of Landlord and Tenant or Tenant's use of the Demised Premises or
the Common Areas and if Tenant shall acquire a lien on or interest in any other
properties or assets by judgment or otherwise, Tenant shall promptly release
such lien on or interest in such other properties and assets by executing,
acknowledging and delivering to Landlord an instrument to that effect prepared
by Landlord's attorneys. Tenant hereby waives the right of specific performance
and any other remedy allowed in equity if specific performance or such other
remedy could result in any liability of Landlord for the payment of money to
Tenant or to any third party.

                                   ARTICLE 24
                              DAMAGE OR DESTRUCTION

             24.01. If the Building or the Demised Premises shall be partially
or totally damaged or destroyed by fire, earthquake or other casualty (and if
this Lease shall not be terminated as provided in this Article 24), Landlord
shall repair the damage and restore and rebuild the Building and/or the Demised
Premises (except for the Tenant's Property, Tenant's Initial Improvements or any
alterations or improvements to the Demised Premises requested or performed by
Tenant) with reasonable dispatch after notice to it of the damage or destruction
and the actual collection by Landlord of the insurance proceeds attributable to
such damage by Landlord, subject to the consent of the Superior Mortgagee under
any Superior Mortgage.

             24.02. Subject to the provisions of Section 24.05, if all or part
of the Demised Premises shall be damaged or destroyed or rendered completely or
partially untenantable on account of fire, earthquake or other casualty, the
Rent shall be abated or reduced, as the case may be, in the proportion that the
untenantable area of the Demised Premises bears to the total area of the Demised
Premises, for the period from the date of the damage or destruction to (a) the
date the damage to the Demised Premises shall be substantially repaired, or (b)
if the Building and not the Demised Premises is so damaged or destroyed, the
date on which the Demised Premises shall be made tenantable; provided however,
should Tenant reoccupy a portion of the Demised Premises during the period the
repair or restoration work is taking place and prior to the date that the
Demised Premises are substantially repaired or made tenantable, the Rent
allocable to such reoccupied portion based upon the proportion which the area of
the reoccupied portion of the Demised Premises bears to the total area of the
Demised Premises, shall be payable by Tenant from the date of such occupancy.

             24.03. If (a) the Building or the Demised Premises shall be totally
damaged or destroyed by fire, earthquake or other casualty, or (b) the Building
shall be so damaged or destroyed by fire, earthquake or other casualty (whether
or not the Demised Premises are damaged or

                                       32
<PAGE>

destroyed) that its repair or restoration requires the expenditure, as estimated
by a reputable contractor or architect designated by Landlord, of more than
twenty (20%) percent (or ten (10%) percent if such casualty occurs during the
last two (2) years of the Term) of the full insurable value of the Building
immediately prior to the casualty, or (c) the Building shall be damaged or
destroyed by fire, earthquake or other casualty (whether or not the Demised
Premises are damaged or destroyed), and (i) the loss shall not be covered by
Landlord's insurance or (ii) Superior Mortgagee does not consent to make the
proceeds of any insurance available for restoration subject to the terms of any
Superior Mortgage, or (iii) the net insurance proceeds (after deducting all
expenses in connection with obtaining such proceeds) shall, in the estimation of
a reputable contractor or architect designated by Landlord, be insufficient to
pay for the repair or restoration work, then, in any such case Landlord may
terminate this Lease by giving Tenant notice to such effect within ninety (90)
days after the date of the fire, earthquake or other casualty and the Lease
shall terminate sixty (60) days thereafter.

             24.04. Tenant shall not be entitled to terminate this Lease and no
damages, compensation or claim shall be payable by Landlord for inconvenience,
loss of business or annoyance arising from any repair or restoration of any
portion of the Demised Premises or of the Building pursuant to this Article 24.
Landlord shall use its best efforts to make such repair or restoration promptly
and in such manner as to not unreasonably interfere with Tenant's use and
occupancy of the Demised Premises, but Landlord shall not be required to do such
repair or restoration work except during Business Hours on Business Days.
Landlord shall not be required to restore fixtures, improvements or other
property of Tenant. The word "restore" as used in this Article shall include
repairs.

             24.05. Notwithstanding any of the foregoing provisions of this
Article 24, if solely by reason of some intentional act or omission on the part
of Tenant or any of its subtenants or its or their partners, directors,
officers, servants, employees, agents or contractors, either (a) Landlord, any
Superior Lessor or any Superior Mortgagee shall be unable to collect all of the
insurance proceeds (including without limitation, rent insurance proceeds)
applicable to damage or destruction of the Demised Premises or the Building by
fire, earthquake or other casualty, or (b) the Demised Premises or the Building
shall be damaged or destroyed or rendered completely or partially untenantable
on account of fire, earthquake or other casualty, then without prejudice to any
other remedies which may be available against Tenant, there shall be no
abatement or reduction of Rent. Further, nothing contained in this Article 24
shall relieve Tenant from any liability that may exist as a result of any damage
or destruction by fire, earthquake or other casualty.

                                       33
<PAGE>

             24.06. Landlord will not carry insurance of any kind on the
Tenant's Property or Tenant's Initial Improvements, and, except as provided by
law or by reason of Landlord's breach of any of its obligations hereunder, shall
not be obligated to repair any damage or to replace the Tenant's Property or
Tenant's Initial Improvements

             24.07. The provisions of this Article 24 shall be deemed an express
agreement governing any case of damage or destruction of the Demised Premises
and/or Building by fire, earthquake or other casualty, and any law providing for
such contingency in the absence of an express agreement, now or hereafter in
force, shall have no application in such case.

                                   ARTICLE 25
                                 EMINENT DOMAIN

             25.01. If the whole of the Demised premises shall be taken by any
public or quasi-public authority under the power of condemnation, eminent domain
or expropriation, or in the event of conveyance of the whole of the Demised
Premises in lieu thereof, this Lease shall terminate as of the day possession
shall be taken by such authority. If 25% or less of the square footage of the
Demised Premises shall be so taken or conveyed, this Lease shall terminate only
in respect of the part so taken or conveyed as of the day possession shall be
taken by such authority. If more than 25% of the square footage of the Demised
Premises shall be so taken or conveyed, this Lease shall terminate only in
respect of the part so taken or conveyed as of the day possession shall be taken
by such authority, but either party shall have the right to terminate this Lease
upon notice given to the other party within thirty (30) days after such taking
of possession. If more than 25% of the square footage of the Building shall be
so taken or conveyed, Landlord, may, by notice to Tenant, terminate this Lease
as of the day possession shall be taken. If this Lease shall continue in effect
as to any portion of the Demised Premises not so taken or conveyed, the Rent
shall be computed as of the day possession shall be taken on the basis of the
remaining square footage of the Demised Premises. Except as specifically
provided herein, in the event of any such taking or conveyance there shall be no
reduction in Rent. If this Lease shall continue in effect. Landlord shall, at
its expense, but shall be obligated only to the extent of the net award or other
compensation (after deducting all expenses in connection with obtaining the
award or other compensation), available to Landlord for the improvements taken
or conveyed (excluding any award or other compensation for land or for the
unexpired portion of the term of any Superior Lease), make all necessary
alterations so as to constitute the remaining Building a complete architectural
and tenantable unit, except for the Tenant's Property, and Tenant shall make all
alterations or replacements to the Tenant's Property and decorations in the
Demised Premises. All awards and compensation for any taking or conveyance,
whether for the whole or a part of the Land or Building, the Demised Premises or
otherwise, shall be the property of Landlord, and Tenant hereby assigns to
Landlord all of Tenant's right, title and interest in and to any and all such
awards

                                       34
<PAGE>

and compensation, including, without limitation, any award or compensation for
the value of the unexpired portion of the Term. Tenant shall be entitled to
claim, prove and receive in the condemnation proceeding such award or
compensation as may be separately awarded by the court for the Tenant's
non-depreciated leasehold improvements and for loss of business, goodwill, and
depreciation or injury to and cost of removal of the Tenant's Property.

             25.02. This Lease shall be and remain unaffected by such taking and
Tenant shall continue to be responsible for all of its obligations hereunder
insofar as such obligations are not affected by such taking and shall continue
to pay the Rent in full when due.

                                   ARTICLE 26
                                    SURRENDER

             26.01. On the Expiration Date, or upon any earlier termination of
this Lease, or upon any re-entry by Landlord upon the Demised Premises, Tenant
shall quit and surrender the Demised Premises to Landlord "broom-clean" and in
good order, condition and repair, except for ordinary wear and tear and such
damage or destruction as Landlord is required to repair or restore under this
Lease. Tenant shall also remove all of Tenant's Property therefrom at the
expiration or termination of the Lease, except as otherwise expressly provided
in this Lease.

             26.02. If Tenant remains in possession of the Demised Premises
after the expiration of the Term, Tenant shall be deemed to be occupying the
Demised Premises as a tenant from month to month at the sufferance of Landlord
subject to all of the provisions of this Lease, except that the monthly Fixed
Rent shall be 150% of the then monthly Fixed Rent and Additional Rent in effect
during the last month of the Term or any Renewal Period.

             26.03. No act or thing done by Landlord or its agents shall be
deemed an acceptance of or a surrender of the Demised Premises, and no agreement
to accept such surrender shall be valid unless in writing and signed by
Landlord.

                                   ARTICLE 27
                            CONDITIONS OF LIMITATION

             27.01. This Lease is subject to the limitation that whenever Tenant
or a guarantor, if any, (a) shall make an assignment for the benefit of
creditors, or (b) shall commence a voluntary case or have entered against it an
order for relief under any chapter of the Federal Bankruptcy Code (Title 11 of
the United States Code) or any similar order or decree under any federal or
state law, now in existence or hereafter enacted having the same general
purpose, and such order or decree shall have not been stayed or vacated within
30 days after entry, or (c) shall cause, suffer, permit or consent to the
appointment of a receiver, trustee, administrator, conservator, sequestrator,
liquidator or similar official in any federal, state or foreign judicial or

                                       35
<PAGE>

nonjudicial proceeding, to hold, administer and/or liquidate all or
substantially all of its assets, and such appointment shall not have been
revoked, terminated, stayed or vacated and such official discharged of his
duties within 30 days of his appointments then Landlord, at any time after the
occurrence of any such event, may give Tenant a notice of intention to end the
Term at the expiration of five (5) days from the date of service of such notice
of intention, and upon the expiration of said five (5) day period, whether or
not the Term shall theretofore have commenced, this Lease shall terminate with
the same effect as if that day were the Expiration Date of this Lease, but
Tenant shall remain liable for damages as provided in Article 29.

             27.02. This Lease is subject to the further limitations that: (a)
if Tenant shall default in the payment of any Rent, and such default shall
continue for ten (10) days after the due date, or (b) if Tenant shall, whether
by action or inaction, be in default of any of its obligations under this Lease
(other than a default in the payment of Rent) and such default shall continue
and not be remedied within thirty (30) days after Landlord shall have given to
Tenant a notice specifying the same, or, in the case of default which cannot
with due diligence be cured within a period of thirty (30) days and the
continuance of which for the period required for cure will not subject Landlord,
Superior Mortgagor or Superior Lessor to prosecution for a crime (as more
particularly described in the last sentence of Section 12.02.) or termination of
any Superior Lease or foreclosure of any Superior Mortgage, if Tenant shall not,
(i) within said ten (10) day period advise Landlord of Tenant's intention to
take all steps necessary to remedy such default, (ii) duly commence within said
ten (10) day period and thereafter diligently prosecute to completion all steps
necessary to remedy the default, and (iii) to complete such remedy within a
reasonable time after the date of said notice by Landlord, or (c) if any event
shall occur or any contingency shall arise whereby this Lease would, by
operation of law or otherwise, devolve upon or pass to any person, firm or
corporation other than Tenant, except as expressly permitted by Article 11, or
(d) if Tenant shall abandon the Demised Premises, then in any of said cases
Landlord may give to Tenant a notice of intention to end the Term at the
expiration of five (5) days from the date of the service of such notice of
intention, and upon the expiration of said five (5) days, whether or not the
Term shall theretofore have commenced, this Lease shall terminate with the same
effect as if that day were the Expiration Date of this Lease, but Tenant shall
remain liable for damages as provided in Article 29. The indemnity provisions
contained herein shall survive the expiration or earlier termination of this
Lease.

                                   ARTICLE 28
                              RE-ENTRY BY LANDLORD

             29.01. If Tenant shall default in the payment of any Rent, and such
default shall continue for ten (10) days after notice thereof, or if this Lease
shall terminate as provided in Article 27, Landlord or Landlord's agent and
employees may immediately or at any time thereafter

                                       36
<PAGE>

re-enter the Demised Premises, or any part thereof, either by summary dispossess
proceedings or by any suitable action or proceeding at law, or otherwise,
without terminating the Lease and without being liable to indictment,
prosecution or damages therefor, and may repossess the same, and may remove any
Person therefrom, to the end that Landlord may have, hold and enjoy the Demised
Premises. The word "re--enter" as used herein, is not restricted to its
technical legal meaning. If this Lease is terminated under the provisions of
Article 27, or if Landlord shall re-enter the Demised Premises under the
provisions of this Article 28, or in the event of the termination of this Lease,
or of re-entry, by or under any summary dispossess or other proceedings or
action or any provision of law by reason of default hereunder on the part of
Tenant, Tenant shall thereupon pay to Landlord the Rent payable up to the time
of such termination of this Lease, or of such recovery of possession of the
Demised Premises by Landlord, as the case may be, and shall also pay to Landlord
damages as provided in Article 29.

             28.02. In the event of a breach or threatened breach by a party of
any of its obligations under this Lease, the other party shall also have the
right of injunction.

             28.03. If this Lease shall terminate under the provisions of
Article 27, or if Landlord shall re--enter the Demised Premises under the
provisions of this Article 28, or in the event of the termination of this Lease,
or re-entry, by or under any summary dispossess or other proceeding or action or
any provision of law by reason of default hereunder on the part of Tenant,
Landlord shall be entitled to retain all monies, if any, paid by Tenant to
Landlord whether as Advance Rent, Security Deposit (and interest thereon, if
any) or otherwise, but such monies shall be credited by Landlord against any
Rent due from Tenant at the time of such termination or re-entry or, at
Landlord's option, against any damages payable by Tenant under Article 29 or
pursuant to law.

                                   ARTICLE 29
                                     DAMAGES

             29.01. If this Lease is terminated under the provisions of Article
27, or if Landlord shall re--enter the Demised Premises under the provisions of
Article 28, or in the event of the termination of this Lease, or of re-entry, by
or under any action to obtain possession in a summary manner or other proceeding
or action or any provision of law by reason of default hereunder on the part of
Tenant, Tenant shall pay an Additional Rent to Landlord as a condition precedent
to the dismissal of any action to obtain possession of the Demised Premises or
other proceeding or action for damages, at the election of Landlord, either:

             (a) A sum which at the time of such termination of this Lease or at
             the time of any such re--entry by Landlord, as the case may be,
             represents the then present value, calculated utilizing the prime
             interest rate declared by Chase Bank, N.A. in New York as of the
             date of default, of the aggregate

                                       37
<PAGE>

             amount of the Rent which would have been payable by Tenant
             (conclusively presuming the average monthly Additional Rent to be
             the same as were the average monthly Additional Rent payable for
             the year, or if less than 365 days have then elapsed since the
             Commencement Date, the partial year, immediately preceding such
             termination or re-entry) for the period commencing with such
             earlier termination of this Lease or the date of any such re-entry,
             as the case may be, and ending with the Expiration Date plus legal
             and expert fees and costs for the bringing of any action to enforce
             this provision. In exercising this remedy, Landlord shall be
             entitled to accelerate all unpaid Rent and other amounts due
             hereunder until the Expiration Date; or

             (b) Sums equal to the Fixed Rent and the Additional Rent which
             would have been payable by Tenant had this Lease not so terminated,
             or had Landlord not so re--entered the Demised Premises, payable
             upon the due dates therefor specified herein following such
             termination or such re--entry and until the Expiration Date,
             provided, however, that if Landlord shall relet the Demised
             Premises during said period, Landlord shall credit Tenant with the
             net rents received by Landlord from such reletting, such net rents
             to be determined by first deducting from the gross rents as and
             when received by Landlord from such reletting the expenses incurred
             or paid by Landlord in terminating this Lease or in reentering the
             Demised Premises and in securing possession thereof, as well as the
             expense of reletting, including, without limitation, altering and
             preparing the Demised Premises for new tenants, brokers'
             commissions, legal fees, and all other expenses properly chargeable
             against the Demised Premises and the rental therefrom, it being
             understood that any such reletting may be for a period shorter or
             longer than the period ending on the Expiration Date; but in no
             event shall Tenant be entitled to receive any excess of such net
             rents over the sums payable by Tenant to Landlord hereunder, nor
             shall Tenant be entitled in any suit for the collection of damages
             pursuant to this subdivision (b) to a credit in respect of any
             rents from reletting, except to the extent that such net rents are
             actually received by Landlord. If the Demised Premises or any part
             thereof should be relet in combination with other space, then
             proper apportionment on a square foot basis shall be made of the
             rent received from such reletting and of the expenses of reletting.

             If the Demised Premises or any part thereof be relet by Landlord
before presentation of proof of such damages to any Court, commission or
tribunal, the amount of rent reserved upon such reletting shall, prima facia, be
the fair and reasonable rental value for the Demised Premises, or part thereof,
to relet during the term of the reletting. Landlord shall have no obligation to
mitigate damages by reletting the Demised Premises and shall not be liable in
any way whatsoever for its failure or refusal to relet the Demised Premises or

                                       38
<PAGE>

any part thereof, or if the Demised Premises or any part thereof are relet, for
its failure to collect the rent under such reletting, and no such failure or
refusal to relet or failure to collect the rent shall release or affect Tenant's
liability for damages or otherwise under this Lease. Landlord shall be under no
obligation in reletting the Demised Premises to give priority to the leasing
thereof over other vacant space in the Building.

             29.02. Suit or suits for the recovery of any such damages, or any
installments thereof, may be brought by Landlord at any time and from time to
time at its election, and nothing contained herein shall be deemed to require
Landlord to postpone suit until the date when the Term would have expired if it
had not been so terminated under the provisions of Article 27 or under any
provision of law, or had Landlord not re-entered the Demised Premises. Nothing
herein contained shall be construed to limit or preclude recovery by Landlord
against Tenant of any sums or damages to which, in addition to the damages
particularly provided above, Landlord may lawfully be entitled by reason of any
default hereunder on the part of Tenant. Nothing herein contained shall be
construed to limit or prejudice the right of Landlord to prove and/or obtain as
damages by reason of the termination of this Lease or re--entry on the Demised
Premises for the default of Tenant under this Lease an amount equal to the
maximum amount permitted by any statute or rule of law in effect at the time
when the governing proceedings have been initiated, whether or not such amount
is greater than, equal to, or less than any of the sums referred to in Section
29.01.

             29.03. In addition, if this Lease is terminated under the
provisions of Article 27, or if Landlord shall re--enter the Demised Premises
under the provisions of Article 28, Tenant covenants that: (a) the Demised
Premises then shall be in the same condition as that in which Tenant has agreed
to surrender the same to Landlord at the Expiration Date; (b) Tenant shall have
performed prior to any such termination any obligation of Tenant contained in
this Lease for the making of any alteration or for restoring or rebuilding the
Demised Premises or the Building, or any part thereof; and (c) for the breach of
any covenant of Tenant set forth above in this Section 29.03, Landlord shall be
entitled immediately without notice or other action by Landlord, to recover, and
Tenant shall pay as and for liquidated damages therefor, the cost of performing
such covenant (as estimated by an independent contractor selected by Landlord).

             29.04. In addition to any other remedies Landlord may have under
this Lease, and without reducing or adversely affecting any of Landlord's rights
and remedies under this Article 29, if any Rent or damages payable hereunder by
Tenant to Landlord are not paid within five (5) days after notice therefor, the
same shall bear interest at the Late Payment Rate pursuant to Section 3.05 from
the due date thereof until paid, and the amount(s) of such interest shall be
Additional Charges hereunder.

                                       39
<PAGE>

             29.05. In addition to any remedies which Landlord may have under
this Lease, if there shall be a default hereunder by Tenant which shall not have
been remedied within the applicable grace period, Landlord shall not be
obligated to furnish to Tenant or the Demised Premises any HVAC services, or any
building services; and the discontinuance of any one or more of such services
shall be without liability by Landlord to Tenant and shall not reduce, diminish
or otherwise affect any of Tenant's covenants and obligations under this Lease.

                                   ARTICLE 30
                               AFFIRMATIVE WAIVERS

             30.01. Tenant, on behalf of itself and any and all persons claiming
through or under Tenant, does hereby waive and surrender all right and privilege
which it, they or them might have under or by reason of any present or future
law, to redeem the Demised Premises or to have a continuance of this Lease after
being dispossessed or ejected from the Demised Premises by process of Law or
under the terms of this Lease or after the termination of this Lease as provided
in this Lease.

             30.02. Landlord and Tenant hereby waive trial by jury in any
action, proceeding or counterclaim brought by either against the other on any
matter whatsoever arising out of or in any way connected with this Lease, the
relationship of Landlord and Tenant, and Tenant's use or occupancy of the
Demised Premises and use of the Common Area, including without limitation, any
claim of injury or damage, and any emergency and other statutory remedy with
respect thereto. Tenant shall not interpose any counterclaim of any kind in any
action or proceeding commenced by Landlord to recover possession of the Demised
Premises.

                                   ARTICLE 31
                                   NO WAIVERS

             31.01. The failure of the Landlord to insist in any one or more
instances upon the strict performance of any one or more of the obligations of
this Lease, or to exercise any election herein contained, shall not be construed
as a waiver or relinquishment for the future of the performance of such one or
more obligations of this Lease or of the right to exercise such election, but
the same shall continue and remain in full force and effect with respect to any
subsequent breach, act or omission. The receipt by Landlord of Fixed Rent or
Additional Rent with knowledge of breach by Tenant of any obligation of this
Lease shall not be deemed a waiver of such breach.

                                   ARTICLE 32
                            CURING TENANT'S DEFAULTS

             32.01. If Tenant shall default in the performance of any of
Tenant's obligations under this Lease, Landlord, without thereby waiving such
default, may (but shall not be obligated to) perform the same for the account
and at the expense of Tenant, without notice in a case of

                                       40
<PAGE>

emergency, and in any other case only if such default continues after the
expiration of ten (10) days from the date Landlord gives Tenant notice of the
default. Bills for any expenses incurred by Landlord in connection with any such
performance by it for the account of Tenant, and bills for all costs, expenses
and disbursements of every kind and nature whatsoever, including reasonable
attorney's fees and expenses, involved in collecting or endeavoring to enforce
any rights against Tenant or Tenant's obligations hereunder, under or in
connection with this Lease or pursuant to law, including any such cost, expense
and disbursement involved in instituting and prosecuting legal proceedings or in
recovering possession of the Demised Premises after default by Tenant or upon
the expiration of the Term or sooner termination of this Lease, including
attorneys fees and costs for any bankruptcy proceedings, and interest on all
sums advanced by Landlord under this Article at the interest rate provided in
Section 3.05 may be sent by Landlord to Tenant monthly, or immediately at
Landlord's option and such amounts shall be due and payable in accordance with
the terms of such bills.

                                   ARTICLE 33
                                     BROKER

             33.01. Parties represent that no broker except the Broker was
instrumental in bringing about or consummating this Lease and that the parties
have had no conversations or negotiations with any broker except the Broker
concerning the leasing of the Demised Premises. Parties agree to indemnify and
hold harmless each other against and from any claims for any brokerage
commissions and all costs, expenses and liabilities in connection therewith,
including, without limitation, attorneys' fees and expenses, arising out of any
conversations or negotiations had by each with any broker other than the Broker.
Landlord and Tenant shall pay any brokerage commissions due the Broker for the
leasing of the Demised Premises as defined in Section 1.01(J) pursuant to a
separate agreement between Landlord, Tenant and the Broker.

                                   ARTICLE 34
                                     NOTICES

             34.01. Any notice, statement, demand, consent, approval or other
communication required or permitted to be given, rendered or made by either
party to the other, pursuant to this Lease or pursuant to any applicable Legal
Requirement, shall be in writing and shall be deemed to have been properly
given, rendered or made only if hand delivered, or delivered by any nationally
recognized over-night delivery service, or sent by United States registered or
certified mail, return receipt requested, addressed to the other party at the
following addresses;

             As to Tenant:      Advanced Telecommunications, Inc.
                                730 Second Avenue South
                                Suite 1200
                                Minneapolis, Minnesota 55402

                                       41
<PAGE>

             With a copy to:    David L. Mitchell, Esq.
                                Robins, Kaplan, Miller & Ciresi, L.L.P.
                                2800 LaSalle Plaza
                                800 LaSalle Avenue
                                Minneapolis, Minnesota 55402-2015

             As to Landlord:    Seattle Telecom LLC
                                750 Lexington Avenue, 28th Floor
                                New York, NY 10022
                                Attn: Oskar Brecher, Manager

             With a copy to:    Eugene T. Paolino, Esq.
                                Schumann, Hanlon, Doherty,
                                   McCrossin & Paolino
                                30 Montgomery Street -- 15th Floor
                                Jersey City, New Jersey 07302

             Any such notices shall be deemed to have been given, rendered or
made on the date received if delivered by hand or the second day after the day
so mailed unless mailed outside the State of Washington, in which case it shall
be deemed to have been given, rendered or made on the third Business Day after
the day so mailed. Either party may, by notice as aforesaid, designate a
different address or addresses for notices, statements, demands, consents,
approvals or other communications intended for it.

                                   ARTICLE 35
                            ESTOPPEL CERTIFICATES

             35.01. Each party shall, at any time and from time to time, as
requested by the other party, upon not less than thirty (30) days' prior notice,
execute and deliver to the requesting party a statement certifying that this
Lease is not modified and in full force and effect (or if there have been
modifications, that the same is in full force and effect as modified and stating
the modifications), certifying the dates to which the Fixed Rent and Additional
charges have been paid, stating whether or not, to the best knowledge of the
party giving the statement, the requesting party is in default in performance of
any of its obligations under this Lease, and, if so, specifying each such
default of which the party giving the statement shall have knowledge and stating
whether or not, to the best knowledge of the party giving the statement, any
event has occurred which with the giving of notice or passage of time, or both,
would constitute such a default of the requesting party, and, if so, specifying
each such event; and such statement delivered pursuant hereto shall be deemed a
representation and warranty to be relied upon by the party requesting the
certificate and by others with whom such party may be dealing, regardless of
independent investigation. Tenant also shall include in any such statement such
other information concerning this Lease as Landlord may reasonably request.

                                       42
<PAGE>

                                   ARTICLE 36
                                   ARBITRATION

             36.01. Landlord may at any time request arbitration, and Tenant may
at any time when not in default in the payment of any Rent request arbitration,
of any matter in dispute but only where arbitration is expressly provided for in
this Lease. Such dispute shall be submitted to the arbitration of three (3)
disinterested persons, one of whom shall be chosen by each of the parties
hereto, and the third by the two arbitrators so chosen; and the award and
finding of said arbitrators, or of any two of them, shall be final and
conclusive on any questions or matters so submitted to them. In case an
arbitration is not otherwise arranged, either party desiring such submission to
arbitration shall notify the other party in writing of the matter which it
desires to submit to arbitration, designating its arbitrator in such notice.
Within twenty (20) days thereafter, the party thus notified shall name its
arbitrator, and notify the other party of such selection. The arbitrators thus
selected shall immediately proceed to select the third arbitrator as aforesaid,
and with him to consider and determine all matters submitted. In case the party
notified of the desired submission to arbitration shall fail, upon due
notification, to name an arbitrator, the arbitrator selected by the other party
shall have the right to proceed alone and determine the matters thus submitted,
and his award shall be final and conclusive upon the parties hereto. In the
event that the two arbitrators first selected shall be unable to agree upon the
third arbitrator within twenty (20) days after the selection of the second
arbitrator, either party hereto, upon giving ten (10) days' notice in writing to
the other party, or to the arbitrator selected by such other party, may apply to
the Courts of the State of Washington for the appointment of a third arbitrator,
and any arbitrator appointed by such Court upon such application shall have the
same powers and duties as if appointed by the two arbitrators first selected as
hereinbefore provided. The award in such arbitration may be enforced on
application of either party by the order or judgment of a Court of competent
jurisdiction.
             36.02. If any delay in complying with any requirement of this Lease
by Landlord might subject Tenant to any fine or penalty, or to prosecution for a
crime, or materially interfere with Tenant's use and enjoyment of the Demised
Premises or its access thereto, of if it would constitute a default by Tenant
under any permitted mortgage, or of any of the foregoing, Tenant shall have the
right to remedy such default and in such event the sole question to be
determined by the arbitrators shall be whether Landlord is liable for Tenant's
costs and expenses of curing such default.

             36.03. Each party to the arbitration shall pay the costs or fees of
the arbitrator selected by it and all further costs and fees, including Court
costs in connection with the arbitration, shall be shared equally by the two
parties to the arbitration. Each party shall bear the cost of its own attorneys
and experts and the additional expenses of presenting its own proofs. Any
arbitration under this Article shall be governed and controlled, except as
otherwise provided

                                       43
<PAGE>

herein, by the rules of the American Arbitration Association in the city of
Seattle, Washington.

                                   ARTICLE 37
                                 RENEWAL OPTION

             37.01 Tenant shall have the option to renew this Lease for two (2)
additional periods ("the First Renewal Period" and "the Second Renewal Period")
for a further period of five (5) years for each such Renewal Period provided
Tenant is not in default under any terms of this Lease. Tenant shall give
written notice to the Landlord ("Renewal Notice") at least 270 days prior to the
Expiration Date with respect to the First Renewal Period or twelve 270 days
prior to the expiration of the First Renewal Period with respect to the Second
Renewal Period. Except for this Article 37 and, further except for the amount of
Fixed Rent as set forth in Article 1, all other terms and conditions of this
Lease shall continue during the First Renewal Period and the Second Renewal
Period. The Fixed Rent shall be the fair market rental for comparable space
within the Building. In the event that the parties are unable to agree as to the
fair market rent within sixty (60) days after the date of the Renewal Notice,
then the Fixed Rent shall be determined by an independent appraiser selected by
Landlord in its sole reasonable discretion which appraiser shall have at least
fifteen (15) years experience in the real estate industry of Seattle, Washington
and shall be familiar with the real estate requirements of the
telecommunications industry. The determination of such appraiser shall be
binding on the parties; however, in no event shall Fixed Rent for any Renewal
Period be less than the Fixed Rent for the Initial Term of the Lease or the
immediately prior Renewal Period, as the case may be.

                                   ARTICLE 38
                                  BUILDING NAME

             38.01. The Building may be designated and known by any name or
address Landlord may choose from time to time in Landlord's sole discretion.
Tenant agrees not to refer to the Building by any name or address other than as
designated by Landlord. The Building may be named after any person, firm, or
otherwise, whether or not such name is, or resembles, the name of a tenant of
the Building. In no event shall Tenant use, in connection with its business or
otherwise, any photographic or other type of representation of the Building. In
the event the Building is named after any person, firm or otherwise, Tenant, in
connection with its business or otherwise, shall not refer to the Building by
such name but shall only use the street address of the Building.

             38.02. Subject to Landlord's sole reasonable approval, Tenant shall
have the right to place a sign on or around the Building provided same does not
denigrate the character of the Building and is aesthetically suitable. Any sign
placed on the Building by Tenant shall not be equal to or larger than any sign
on the Building placed by U.S. West. Tenant shall be responsible for and shall
pay all costs and

                                       44
<PAGE>

expenses for the installation and, upon termination of the Lease or when
exterior maintenance is to be performed on the Building, for removal of any such
sign (including, without limitation, restoring the points of affixation).

                                   ARTICLE 39
                               ENVIRONMENTAL LAWS

             39.01. Tenant acknowledges the existence of federal, state and
local environmental laws, rules and regulations including, without limitation,
the Comprehensive Environmental Response, Compensation and Liability Act
(CERCLA) 42 U.S.C. 9601-9657, the Resource Conservation and Recovery Act (RCRA)
42 U.S.C. 6901-6987, laws, rules and regulations of the State of Washington,
governing environmental matters, all of which, together with any successor
Legislation, are collectively referred to hereinafter as the "Environmental
Laws". Tenant agrees, from and after the date hereof, to act in compliance with
the Environmental Laws and that it shall not perform any acts in violation of
the Environmental Laws.

             39.02. Upon the occurrence of any event requiring Tenant's
compliance with Environmental Laws or if Landlord by reason of any act or
omission or failure to act or not act on the part of Tenant, shall be required
to comply with Environmental Laws, Tenant shall make all necessary filings with
the appropriate governmental agency and any other relevant federal, state,
county or municipal legal authority and, at its own expense, shall cause all
necessary tests and studies to be performed. Landlord shall complete such
documents and otherwise cooperate (provided such cooperation does not subject
Landlord to any fee, cost, expense or liability or require performance by
Landlord of Tenant's obligation hereunder) as may be reasonably requested by
Tenant or required by the Environmental Laws. In the event an environmental
clean-up is required, the Landlord shall have an unrestricted right to inspect,
as often as it deems necessary in its sole discretion, during and after such
clean-up.

             39.03. Tenant hereby agrees to execute such documents and provide
such information as Landlord reasonably requires to assure compliance with the
Environmental Laws, and rules or regulations of any other relevant federal,
state, county or municipal legal authority. Tenant shall bear all costs and
expenses incurred by Landlord associated with any such compliance resulting from
Tenant's use of the Demised Premises or any acts and/or omissions which Tenant,
its agents, employees, invitees or independent contractors initiate, including,
without limitation, state agency fees, engineering fees, clean-up costs, filing
fees and suretyship expenses. Tenant agrees to indemnify, defend and hold
Landlord harmless from and against any fines, suits, proceedings, claims and
actions and any other cost, expense or liability of any kind arising under the
Environmental Laws, rules or regulations resulting from Tenant's failure to
comply with this Article 39 or Tenant's failure to provide all information, make
all submissions and take all actions required by any legal authority, including
reasonable attorney's fees.

                                       45
<PAGE>

             39.04. Tenant shall immediately provide Landlord with copies of all
correspondence, reports, notices, orders, findings, declarations and other
materials pertinent to Tenant's compliance hereunder or any other environmental
enforcement requirements under any Environmental Laws as they are issued or
received by Tenant. More specifically, but not limiting the foregoing, Tenant
shall promptly provide Landlord with any notices, correspondence and submissions
made by Tenant to the United States Environmental Protection Agency, the United
States Occupational Safety and Health Administration, or any other legal
authority which requires submission of any information concerning environmental
matters of hazardous wastes or substances, and any notices, correspondence,
documents and directives received by Tenant from any of said authorities.

             39.05. In addition to any other remedies of Landlord pursuant to
this Lease, Tenant's failure to abide by the terms of this Article 39 shall
survive the Expiration Date or earlier termination of the Term of this Lease.
Tenant's failure to abide by the terms of this Article shall be restrainable by
injunction.

             39.06. Tenant shall indemnify, defend and hold Landlord, Superior
Lessors and Superior Mortgagees harmless from and against all claims,
liabilities, losses, damages and costs, foreseen or unforeseen, including
without limitation, reasonable attorney's fees, engineering and other
professional and expert fees and costs, which Landlord or such other indemnified
parties may incur by reason of Tenant's action or non-action with regard to
Tenant's obligations under this Article.

             39.07. The parties agree that the Americans with Disabilities Act,
Hazardous Materials, tax and Y2K disclosure forms shall be completed by both
parties to this transaction.

                                   ARTICLE 40
                                  MISCELLANEOUS

             40.01. Tenant understands and acknowledges that this Lease is a
triple net or absolute net Lease. Tenant further expressly acknowledges and
agrees that Landlord has not made and is not making, and Tenant, in executing
and delivering this Lease, is not relying upon, any warranties, representations,
promises or statements, except to the extent that the same are expressly set
forth in this Lease or in any other written agreement(s) which may be made
between the parties concurrently with the execution and delivery of this Lease.
All understandings and agreements heretofore had between the parties are merged
in this Lease and any other written agreement(s) made concurrently herewith,
which alone fully and completely express the

                                       46
<PAGE>

agreement of the parties and which are entered into after full investigation.
Neither party has relied upon any statement or representation not embodied in
this Lease or in any other written agreement(s) made concurrently herewith. The
provisions of this Lease set forth the enumerated rights of Tenant. Any rights
not specifically provided for herein shall not be deemed or inferred to be given
to Tenant. Any actions taken by Tenant not specifically permitted herein shall
be prohibited.

             40.02. No agreement shall be effective to change, modify, waive,
release, discharge, terminate or effect an abandonment of this Lease in whole or
in part, unless such agreement is in writing, refers expressly to this Lease and
is signed by the party against whom enforcement or the change, modification,
waiver, release, discharge, termination or effectuation of abandonment is
sought.

             40.03. Subject to the Rules and Regulations, Tenant shall be
provided vehicular access for trucks delivering or removing equipment to and
from the Building for the Demised Premises and provided further that any such
vehicular access does not materially impair access to the Building by other
tenants. Landlord may at any time alter or suspend vehicular access to the
Building.

             40.04. If Tenant shall at any time request Landlord to sublet or
let the Demised Premises for Tenant's account, Landlord or its agent is
authorized to receive keys for such purposes without releasing Tenant from any
of its obligations under this Lease, and Tenant hereby releases Landlord from
any liability for loss or damage to any of the Tenant's Property in connection
with such subletting or letting.

             40.05. Except as otherwise expressly provided in this Lease, the
obligations under this Lease shall bind and benefit the successors and assigns
of the parties hereto with the same effect as if mentioned in each instance
where a party is named or referred to; provided, however, that (a) no violation
of the provisions of Article 11 shall operate to vest any rights in any
successor or assignee of Tenant and (b) the provisions of this Section 40.04
shall not be construed as modifying the conditions of limitation contained in
Article 27.

             40.06. Except for Tenant's obligations to pay Rent, the time for
Landlord or Tenant, as the case may be, to perform any of its respective
obligations hereunder shall be extended if and to the extent that the
performance thereof shall be prevented due to any Unavoidable Delays. Except as
expressly provided to the contrary, the obligations of Tenant hereunder shall
not be affected, impaired or excused, nor shall Landlord have any liability
whatsoever too Tenant, (a) because Landlord is unable to fulfill, or is delayed
in fulfilling, any of its obligations under this Lease due to any of the matters
set forth in the first sentence of this Section 40.05, or (b) because of any
failure or defect in the supply, quality or character of electricity, water or
any other utility or service furnished to the Demised Premises for any reason
beyond the Landlord's reasonable control.

                                       47
<PAGE>

             40.07. Any liability for payments hereunder (including, without
limitation, Additional Rent) shall survive the expiration or earlier termination
of this Lease.

             40.08. Tenant shall not exercise its rights under Article 15 or any
other provision of this Lease in a manner which would violate Landlord's union
contracts or create any work stoppage, picketing, labor disruption or dispute or
any interference with the business of Landlord or any tenant or occupant of the
Building.

             40.09. Tenant shall give prompt notice to Landlord of (a) any
occurrence in or about the Demised Premises for which Landlord might be liable,
(b) any fire, earthquake or other casualty in the Demised Premises, (c) any
damage to or defeat in the Demised Premises, including the fixtures and
equipment thereof, for the repair of which Landlord might be responsible, and
(d) any damage to or defect in any part of the Building's sanitary, electrical,
heating, ventilating, air--conditioning, elevator or other systems located in,
on or passing through the Demised Premises or any part thereof.

             40.10. This Lease shall be governed by and construed in accordance
with the laws of the State of Washington. If any provision of this Lease shall
be invalid or unenforceable, the remainder of this Lease shall not be affected
and shall be enforced to the extent permitted by law. The table of contents,
captions, headings and titles in this Lease are solely for convenience of
reference and shall not affect its interpretation. Each covenant, agreement,
obligation or other provision of this Lease on Tenant's part to be performed,
shall be deemed and construed as a separate and independent covenant of Tenant,
not dependent on any other provision of this Lease. All terms and words used in
this Lease, regardless of the number or gender in which they are used, shall be
deemed to include any other number and any other gender as the context may
require.

             40.11. If deemed necessary by Landlord, no person will be allowed
access to the Building without a security pass which shall be issued by Landlord
upon written request of Tenant. Tenant shall be fully liable for the acts of all
persons for whom a security pass is requested. All security passes shall be
returned to Landlord in the event the persons to whom they were issued are no
longer employed by Tenant or are otherwise not entitled to access to the
Building. In no event shall Landlord be liable for its refusal to allow access
to the Building to any person who does not have a security pass.

             40.12. With respect to any provisions of this Lease which provide,
in effect, the Landlord shall not unreasonably withhold or unreasonably delay
any consent or approval, Tenant in no event shall be entitled to make, nor shall
Tenant make, any claim and Tenant hereby waives any claim, for money damages;
nor shall Tenant claim any money damages by way of set-off, counterclaim or
defense, based upon any claim or assertion by Tenant that Landlord has
unreasonably withheld or unreasonably delayed any consent or approval: but
Tenant's sole remedy

                                       48
<PAGE>

shall be an action or proceeding to enforce any such provision, or for specific
performance, injunction or declaratory judgment.

             40.13. To the extent that Landlord, its agents, employees or
licensees have access to the Demised Premises pursuant to the provisions of this
Lease or otherwise, Landlord agrees to indemnify, defend and save harmless
Tenant from and against all bodily harm and personal injury, loss, claim and
damage to or of any person or property of whatever nature arising from any act,
omission, fault, misconduct or negligence of Landlord, or Landlord's
contractors, licensees, agents, servants or employees, unless caused by the
Tenant's negligence or willful misconduct. This indemnity and hold harmless
clause shall include indemnity against all costs, expense and liabilities paid
or incurred in or in connection with any such claim or proceeding brought
thereon and the defense thereof, and shall include reasonable attorney's fees.

             40.14. (a) If Tenant is a corporation, each person executing this
Lease on behalf of Tenant hereby covenants, represents and warrants that Tenant
is a duly incorporated or duly qualified, if a foreign corporation, corporation
and is authorized to do business in the State of Washington (a copy of evidence
thereof shall be supplied by Tenant to Landlord upon request); and that each
person executing this Lease on behalf of Tenant is an officer of Tenant and is
duly authorized to execute, acknowledge and deliver this Lease to Landlord (a
copy of resolution to such effect shall be supplied by Tenant to Landlord upon
request).

             (b) If Tenant is a partnership (or is comprised of two (2) or more
persons, individually, or as joint venturers or as copartners of a partnership),
or if Tenant's interest in this Lease shall be assigned to a partnership (or to
two (2) or more persons, individually, or as joint venturers or as co-partners
of a partnership) (any such partnership and such persons are referred to in this
Article as the "Partnership Tenant"), the following shall apply: (i) the
liability of each of the parties comprising the Partnership Tenant shall be
joint and several (ii) each of the parties comprising the Partnership Tenant
hereby consents in advance to, and agrees to be bound by, any modifications,
termination, discharge or surrender of this Lease which may hereafter be made,
and by any notices which may hereafter be given, by the Partnership Tenant or by
any of the parties comprising the Partnership Tenant, (iii) any notices given or
rendered to the Partnership Tenant or to any of the parties comprising the
Partnership Tenant shall be deemed given or rendered to the Partnership Tenant
and to all such parties and shall be binding upon the Partnership Tenant and all
parties, (iv) if the Partnership Tenant shall admit new partners, all such new
partners shall, by their admission to the Partnership Tenant, be deemed to have
assumed performance of all of the terms of this Lease on Tenants part to be
performed and (v) the Partnership Tenant shall give prompt notice to Landlord of
the admission of any such new partners, and upon demand of Landlord, shall cause
each such new partner to execute and deliver to Landlord and agreement in form
satisfactory to Landlord, wherein each such new partner shall assume

                                       49
<PAGE>

performance of all of the terms of this Lease on Tenant's part to be performed
(but neither Landlord's failure to request any such agreement nor the failure of
any such new partner to execute or deliver any such agreement to Landlord shall
vitiate the provisions of this Section).

             40.15. All Exhibits to this Lease are hereby incorporated into this
Lease, and references to "this Lease" shall include all Exhibits.

             40.16. Tenant shall not place a load upon any floor that exceeds
the floor load per square foot that such floor was designed to carry or which is
allowed by any laws.

             40.17. Tenant acknowledges that there may be noise, dust,
vibrations and other effects from construction work occurring near or about the
Building and that Tenant shall have no claims against Landlord for any
disruption caused by same or interruption or interference with Tenant's business
resulting from same and that Landlord shall have no liability otherwise to
Tenant therefor.

             40.18. In the event Tenant is in arrears in the payment of Rent,
Tenant waives Tenant's right, if any, to designate the items against which any
payments made by or refunds payable to Tenant are to be credited and Landlord
may apply any payments made by Tenant to any items Landlord sees fit,
irrespective of and notwithstanding any designation or requests by Tenant as to
the items against which any such payments shall be credited.

             40.19. In the event Landlord incurs legal, investigative and/or
other professional fees and expenses in connection with any and all attorneys,
expert, or investigative fees and costs incurred by the Landlord in order to
enforce any provision of this Lease or in connection with any request to
Landlord by Tenant for any action, other than that specifically required of the
Landlord pursuant to the provisions of the Lease, then, in that event, the
reasonable cost of such attorneys, investigative and/or other professional fees
and expenses, incurred by the Landlord, shall be paid on demand by Tenant to the
Landlord.

             40.20. The person signing this Lease on behalf of Tenant personally
represents and warrants to Landlord that (i) all action necessary to be taken
and all consents necessary to be obtained to fully authorize the execution,
delivery and performance of this Lease by Tenant has been duly taken or
obtained, as the case may be and (ii) he or she is a duly authorized officer of
Tenant who has full power and authority to execute and deliver this Lease on
behalf of Tenant and bind Tenant to all of the terms and conditions hereof.

                                       50
<PAGE>

             40.21. Except as otherwise provided herein, Landlord shall only be
deemed to be in default under the terms of this Lease if Landlord shall violate,
neglect, or fail to observe, keep or perform any covenant or agreement which is
not observed, kept or performed by Landlord within forty-five (45) days after
receipt by Landlord of written notice by Tenant of such breach which notice
shall specifically set forth the nature of the breach. Landlord shall not be
considered in default so long as Landlord commences to cure the breach in a
diligent and prudent manner and is allowed such additional time as is reasonably
necessary to correct the breach.

             40.22. This Lease may be executed in one or more counterparts, each
of which shall be original, and all of which shall constitute one and the same
instrument.

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

                                          LANDLORD:

                                          SEATTLE TELECOM LLC

                                          BY: GATEWAY REALTY SEATTLE, LLC.,
                                          a Delaware limited liability
ATTEST:                                   company,
                                                a Managing Member

/s/ Kevin A. Booth
-------------------------------------
Name: Kevin A. Booth                      BY: /s/ Kamran Hakim, Manager
     --------------------------------        --------------------------------
Title: Director of Finance                      Kamran Hakim, Manager
      -------------------------------

ATTEST:                                   TENANT:

                                          ADVANCED TELECOMMUNICATIONS, INC.,
                                          a Delaware corporation

-------------------------------------
Name:
     --------------------------------
Title:                                    BY:
      -------------------------------        --------------------------------
                                                Name: Satish Tiwari

                                       83
<PAGE>

             40.21. Except as otherwise provided herein, Landlord shall only be
deemed to be in default under the terms of this Lease if Landlord shall violate,
neglect, or fail to observe, keep or perform any covenant or agreement which is
not observed, kept or performed by Landlord within forty-five (45) days after
receipt by Landlord of written notice by Tenant of such breach which notice
shall specifically set forth the nature of the breach. Landlord shall not be
considered in default so long as Landlord commences to cure the breach in a
diligent and prudent manner and is allowed such additional time as is reasonably
necessary to correct the breach.

             40.22. This Lease may be executed in one or more counterparts, each
of which shall be original, and all of which shall constitute one and the same
instrument.

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

                                          LANDLORD:

                                          SEATTLE TELECOM LLC

                                          BY: GATEWAY REALTY SEATTLE, LLC.,
                                          a Delaware limited liability
ATTEST:                                   company,
                                                a Managing Member

                                          BY:
-------------------------------------        --------------------------------
Name:                                           Kamran Hakim, Manager
     --------------------------------
Title:
      -------------------------------

                                          TENANT:
ATTEST:

                                          ADVANCED TELECOMMUNICATIONS, INC.,
                                          a Delaware corporation

/s/ J. Oxlay                              BY:
-------------------------------------        --------------------------------
Name: J. Jutters Oxlay                    Name: Satish Tiwari
     --------------------------------          ------------------------------
Title: Director of Regulatory Affairs     Title: Vice President/Engineering
      -------------------------------           -----------------------------
                                                 and Network Implementation
                                                -----------------------------

                                       51
<PAGE>

STATE OF MINNESOTA      )
                        )ss:
COUNTY OF HENNEPIN      )

             The foregoing instrument was acknowledged before me this 20th day
of December, 1999, by Satish Tiwari, the Vice President/Engineering and Network
Implementation of Advanced Telecommunications, Inc., a Delaware corporation, on
behalf of the corporation.

[DAVID L. MITCHELL                                  David L. Mitchell
NOTARY PUBLIC STAMP]                           --------------------------
                                                      Notary Public

STATE OF                )
                        )ss.:
COUNTY OF               )

             BE IT REMEMBERED, that on _________, 1999 before me, the
subscriber, a Notary Public of the State of ________________ personally appeared
___________________________ who, being by me duly sworn on his oath, deposed and
made proof to my satisfaction, that he is the __________________ of
________________ a ____________________ corporation, the entity that executed
the within instrument; that deponent knows that __________________________ is
the _________________ of said corporation.

             The execution as well as the making of this instrument has been
duly authorized by a proper resolution of the Board of Directors of the said
corporation; that the deponent well knows the corporate seal of said
corporation; that the seal affixed to the said instrument is the proper
corporate seal and was thereto affixed and said instrument signed and delivered
by said _______________________ as and for the voluntary act and deed of said
corporation in the presence of the deponent who thereupon subscribed his name
thereto as attesting witness.

                                                     ___________________________

                                               Name: ___________________________

Sworn to and subscribed
before me on the date
aforesaid

---------------------------
      Notary Public

[Notarial Seal]

                                       52
<PAGE>

                                    EXHIBIT A

                             DESCRIPTION OF THE LAND
<PAGE>

                                    EXHIBIT B

                        DESCRIBED OF THE DEMISED PREMISES
<PAGE>

                                    EXHIBIT C

                              RULES AND REGULATIONS

       1. Sidewalks, entrances, driveways, passages, courts, elevators,
vestibules, stairways, corridors or halls shall not be obstructed or encumbered
by any tenant or used for any purpose other than for ingress or egress from the
Building and for delivery of merchandise and equipment in a prompt and efficient
manner using elevators and passageways designated for such delivery by Landlord.
There shall not be used in any space, or in the public hall of the Building,
either by any tenant or by jobbers or others in the delivery or receipt of
merchandise, any hand trucks, except those equipped with rubber tires and
sideguards.

       2. The water and wash closets and plumbing fixtures shall not be used for
any purposes other than those for which they were designed or constructed and no
sweepings, rubbish, rags, acids or other substances shall be deposited therein,
and the expense of any breakage, stoppage, or damage resulting from the
violation of this rule shall be borne by the tenant who, or whose clerks,
agents, employees or visitors, shall have caused it.

       3. No tenant shall sweep or throw or permit to be swept or thrown from
the Demised Premises any dirt or other substances into any of the corridors or
halls, elevators, or out of the doors or stairways of the Building and Tenant
shall not use, keep or permit to be used or kept any foul or noxious gas or
substance in the Demised Premises, or permit or suffer the Demised Premises to
be occupied or used in a manner offensive or objectionable to Landlord or other
occupants of the Building by reason of noise, odors, and/or vibrations, or
unreasonably interfere in any way with other tenants or those having business
therein, nor shall any animals or birds be kept in or about the Demised Premises
or the Building. Smoking or carrying lighted cigars or cigarettes in the
elevators of the Building is prohibited.

       4. No awnings or other projections shall be attached to the outside walls
of the Building without the prior written consent of Landlord.

       5. No sign, advertisement, notice or other lettering shall be exhibited,
inscribed, painted or affixed by any tenant on any part of the outside of the
Demised Premises if the same is visible from the outside of the Demised Premises
without the prior written consent of Landlord, except that the name of Tenant or
any subtenant may appear on the entrance door of the Demised Premises. In the
event of the violation of the foregoing by Tenant, Landlord may remove same
without any liability, and may charge the expense incurred by such removal to
tenant(s) violating this rule. Interior signs on doors and a directory tablet,
if any, shall be subject to the prior written approval of Landlord.
<PAGE>

      6. No tenant shall mark, paint, drill into, or in any way deface any part
of the Demised Premises or the Building of which they form a part. No boring,
cutting or installation of electrical wiring shall be permitted, except with the
prior written consent of Landlord, and as Landlord may direct.

      7. No additional locks or bolts of any kind shall be placed upon any of
the doors or windows by any tenant, nor shall any changes be made in existing
locks or mechanisms thereof. Each tenant must, upon the termination of his
tenancy, restore the Landlord all keys of stores, offices and toilet rooms, and
passes to the Building, either furnished to, or otherwise procured by, such
tenant, and in the event of the loss of any keys so furnished, such tenant shall
pay to Landlord the cost thereof.

      8. Freight, furniture, business equipment, merchandise and bulky matter of
any description shall be delivered to and removed from the Demised Premises only
on the freight elevators and through the service entrances and corridors, and
only during Business Hours, and in a manner approved by Landlord. Landlord
reserves the right to inspect all freight to be brought into the Building and to
exclude from the Building all freight which violates any of these Rules and
Regulations of the Lease of which these Rules and Regulations are a part.

      9. Canvassing, soliciting and peddling in the Building are prohibited and
each tenant shall cooperate to prevent the same.

      10. Landlord reserves the right to exclude from the Building at all hours
all persons who do not present a pass to the Building signed by Landlord.
Landlord will furnish passes to persons for whom any tenant requests same in
writing. Each tenant shall be responsible for all persons for whom he requests
such passes and shall be liable to Landlord for all acts of such persons.

      11. Landlord shall have the right to prohibit any advertising by any
tenant which, in Landlord's opinion, tends to impair the reputation of the
Building, or its desirability as a commercial building, including, without
limitation, telecommunications facilities, office, retail and other lawful uses
and upon written notice from Landlord, Tenant shall refrain from or discontinue
such advertising.

      12. Tenant shall not bring or permit to be brought or kept in or on the
Demised Premises, any inflammable, combustible or explosive fluid, material,
chemical or substance (other than chemicals used in ordinary office use in
quantities customary therefor) without the express prior written approval of
Landlord, or cause or permit any odors of cooking or other processes, or any
unusual or other objectionable odors to permeate in or emanate from the
premises.

      13. Tenant agrees to abide by all reasonable rules and regulations issued
by the Landlord with respect to services for heating, ventilating and
air-conditioning.
<PAGE>

      14. Tenant shall not move any safe, heavy machinery, heavy equipment,
bulky matter, or fixtures into or out of the Building without Landlord's prior
written consent which shall not be unreasonably withheld. If such safe,
machinery, equipment, bulky matter or fixtures requires special handling, all
work in connection therewith shall comply with all laws and regulations
applicable thereto and shall be done during such hours as Landlord may
designate.

      15. No Tenant shall use, or permit the use of, fire exits for ingress to
or egress from the Demised Premises. No tenant shall invite to the Demised
premises, or permit the visit of, persons in such numbers or under such
conditions as to interfere with the use and enjoyment of any of the plazas,
entrances, corridors, elevators and other facilities of the Building by the
ground floor tenants. No tenant shall encumber or obstruct, or permit the
encumbrance or obstruction of any of the Retail Premises, or the sidewalks,
plazas, entrances, corridors, elevators, fire exits or stairways of the
Building. Landlord reserves the right to control and operate the public portions
of the Building, the public facilities, as well as facilities furnished for the
common use of tenants, in such manner as Landlord deems best for the benefit of
tenants generally and consistent with a first-class office building with retail
tenants.

      16. The cost of repairing any damage to the public portions of the
Building or the public facilities or to any facilities used in common with other
tenants, caused by a tenant or the employees, licensees or invitees of such
tenants, shall be paid by such tenant as provided in the Lease.

      17. All entrance doors in the Demised Premises shall be left locked when
the Demised Premises are not in use. Entrance doors shall not be left open at
any time.

      18. No bicycles, mopeds or vehicles of any kind shall be kept in or about
the Building or permitted therein.

      19. The exterior windows and doors that reflect or admit light and air
into any premises or the halls, passageways or other public places in the
Building, shall not be covered or obstructed by any tenant, nor shall any
articles be placed on the windowsills.

      20. No acids, vapors or other materials shall be discharged or permitted
to be discharged into the waste lines, vents or flues of the Building which may
damage them.

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