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                                                                   EXHIBIT 10.21


                                     LEASE

This Lease is entered into as of August 6, 1993, between MEPC AMERICAN
PROPERTIES INC., a Delaware Corporation, ("Lessor") and McKESSON CORPORATION, a
Maryland corporation ("Tenant").

1. Definitions. In this Lease:


         (a)      "Building" means the building at 5701 Green Valley Drive,
                  Bloomington, Minnesota 55437, located on the Land, and
                  commonly known as Norman Center IV.

         (b)      "Premises" means all of the rentable space in the Building,
                  which space is shown on the drawings attached to this Lease as
                  Exhibit A, and which for purposes of this Lease will be deemed
                  to contain 29,393 square feet for the period from October 1,
                  1993 through December 31, 1994 and 45,332 square feet
                  thereafter, regardless of actual measurements.

         (c)      "Term" means the period of seven (7) years, beginning on
                  October 1, 1993 and ending on September 30, 2000, subject to
                  the provisions of Section 7 and the other provisions of this
                  Lease.

         (d)      "Commencement Date" means the first day of the Term.

         (e)      "Lease Year" means a 12-month period beginning on the
                  Commencement Date and each successive 12-month period
                  thereafter.

         (f)      "Monthly Base Rent" means $14,700.00 per month for the period
                  from October 1, 1993 through December 31, 1994 and $25,500.00
                  per month for the remainder of the Term, which amounts will
                  not change during the Term.

         (g)      "Costs" means the Tax Costs plus the Operating Costs. For the
                  period from October 1, 1993 through December 31, 1993, the
                  Costs will be deemed to be $16,754.00 per month regardless of
                  the actual amounts of the Costs. For the calendar year 1994,
                  Costs will be deemed to mean 64.84% of the total actual Costs
                  other than those for janitorial services for the Building,
                  plus 100% of the Costs for janitorial services for the
                  Building. Commencing January 1, 1995 Costs will mean 100% of
                  the actual Costs.

         (h)      "Monthly Rent" means the Monthly Base Rent plus the Costs. The
                  initial Monthly Rent is $31,454.00, comprised of a Monthly
                  Base Rent of


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                  $14,700.00 plus monthly Operating Costs of $11,659.00 and
                  monthly Tax Costs of $5,095.00. Commencing on January 1, 1995,
                  the Monthly Rent will be based upon the Monthly Base Rent of
                  $25,500.00 and Costs for 45,332 square feet.

         (i)      "Operating Costs" means all costs, charges and expenses
                  incurred by Lessor in connection with ownership, operation,
                  security, maintenance and repair of the Land, the Building,
                  other improvements on the Land, appurtenances to the Building,
                  parking, roadways, landscaping, lighting, sidewalks, and
                  common or public areas, including but not limited to insurance
                  on common areas, interior and exterior maintenance, insurance,
                  utilities, fees or expenses for management by Lessor or any
                  other party, amortization of capital investments made to
                  reduce Operating Costs, and amortization of repairs made to
                  extend the life of the Building and other improvements.

                  The following items shall be excluded in computing Tenant's
                  share of Operating Costs applicable to the Premises:

                  (1)      Any ground lease rental.

                  (2)      Costs of capital repairs or capital replacements
                           (except as specifically permitted herein), capital
                           improvements and equipment; except those: (a)
                           required by laws enacted on or after the date the
                           temporary certificate of occupancy issued for the
                           Tenant Improvements shall be validly issued with the
                           cost of any such Improvements and equipment
                           depreciated over the useful life of the improvement
                           and/or equipment, or (b) installed at the Premises to
                           reduce Operating Costs, with the cost of any such
                           improvements and equipment depreciated over the
                           useful life of the improvement and/or equipment.

                  (3)      Rentals for items (except when needed in connection
                           with normal repairs and maintenance of the Building
                           which shall be permitted) which if purchased, rather
                           than rented, would constitute a capital improvement
                           specifically excluded in Subsection 2 above.

                  (4)      Costs incurred by Lessor for the repair or
                           replacement of damage to the Building or its contents
                           caused by fire or other casualty.

                  (5)      Costs, including permit, license and inspection
                           costs, incurred with respect to the installation of
                           improvements made for tenants or other occupants in
                           the Building or incurred in

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                           renovating or otherwise improving decorating,
                           painting or redecorating vacant space for tenants or
                           other occupants of the Building.

                  (6)      Depreciation, amortization, lender's fees and
                           interest payments except as permitted pursuant to
                           Subsection 2 above and, if permitted, then determined
                           in accordance with generally accepted accounting
                           principles, consistently applied (as applied to
                           commercial real estate) in accordance with the
                           anticipated useful life of such item (as reasonably
                           determined by Lessor).

                  (7)      Leasing commissions, attorneys' fees, space planning
                           costs, and other costs and expenses in connection
                           with negotiations of this Lease and other present or
                           prospective tenants or other occupants of the
                           Building.

                  (8)      Expenses in connection with services or other
                           benefits which are not offered to Tenant but which
                           are provided to another tenant or occupant of the
                           Building.

                  (9)      Costs incurred by Lessor due to the violation by
                           Lessor or any tenant or occupant of Building (other
                           than Tenant) of the terms and conditions of any lease
                           of space in the Building.

                  (10)     Overhead and profit increments paid to Lessor or to
                           subsidiaries or affiliates of Lessor for goods and/or
                           services in the Building to the extent the same
                           exceeds the costs of such goods and/or services
                           rendered by unaffiliated third parties on a
                           competitive basis.

                  (11)     Interest, principal, points and fees on debts or
                           amortization on any mortgage or mortgages or any
                           other debt instrument encumbering the Building.

                  (12)     Any compensation paid to clerks, attendants or other
                           persons in commercial concessions operated by Lessor
                           in the parking areas of the Building.

                  (13)     All items and services for which Tenant or any tenant
                           or occupant of the Building reimburses Lessor (other
                           than through payment of Operating Costs), or which
                           Lessor provides selectively to one or more tenants or
                           occupants (other than Tenant) without reimbursement.



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                  (14)     Advertising and promotional expenditures, and the
                           costs of acquiring and installing signs in or on the
                           Building identifying the owner of the Building or any
                           tenant or occupant of the Building.

                  (15)     Any costs associated with earthquake insurance, gift
                           taxes, excess taxes or profit taxes, except as
                           provided in paragraph (j) of this Section.

                  (16)     Capital expenditures incurred in connection with
                           upgrading the Building (other than the interior of
                           the Premises) to comply with handicap (ADA),
                           hazardous material, fire and safety codes which were
                           in effect prior to the date of the lease.

                  (17)     Tax penalties incurred as a result of Lessor's
                           negligence, inability or unwillingness to make
                           payments when due, not attributable to Tenant's
                           failure to make payments to Lessor for such items in
                           accordance with the Lease.

                  (18)     All special assessments in excess of $5,000 which can
                           be paid by Lessor in installments, shall be paid by
                           Lessor in the maximum number of installments
                           permitted by law and not included as Operating Costs
                           except in the year in which the assessment
                           installment is actually paid.

                  (19)     Any and all costs arising from the presence of
                           Hazardous Materials in or about the Building,
                           including, without limitation, Hazardous Materials in
                           the groundwater or soil.

                  (20)     Costs arising from Lessor's charitable or political
                           contributions.

                  (21)     Costs to repair defects in the structural portions of
                           the Building, but maintenance and repair of the roof
                           and exterior of the Building may be included unless a
                           capital repair or replacement.

                  (22)     Capital costs for sculpture, paintings, or other
                           objects of art.

                  (23)     Costs (including all related attorneys' fees and
                           costs of settlement judgments and payments in lieu
                           thereof) arising from claims, disputes or potential
                           disputes between Lessor and other tenants of the
                           Building.




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                  (24)     Lessor's general corporate overhead and general
                           administrative expenses, other than management
                           services allocated to the Building.

                  (25)     Costs of any items for which Lessor is reimbursed by
                           insurance, or otherwise compensated by parties other
                           than tenants of the Building.

                  (26)     Costs of overtime or other expenses incurred by
                           Lessor in curing its defaults or performing work
                           expressly provided in the Lease to be borne at
                           Lessor's expense.

                  (27)     Any legal fees associated with the sale or
                           refinancing of the Building.

                  (28)     Damage and repairs necessitated by the negligence or
                           willful misconduct of Lessor or Lessor's employees,
                           contractors or agents.

                  (29)     Interest, penalties or other costs arising out of
                           Lessor's failure to make timely payment of its
                           obligations.

                  (30)     Any other expense which, under generally accepted
                           accounting principles and practice, would not be
                           considered a normal maintenance and operating
                           expense.

                  (31)     Property management fees for a calendar year in
                           excess of 6% of the sum of all Monthly Rent for that
                           calendar year (or for a fiscal year if Lessor uses a
                           fiscal year).

         (j)      "Tax Costs" means all real estate taxes, levies, charges, and
                  installments of assessments (including interest on deferred
                  assessments) assessed, levied or imposed on, or allocated to,
                  the Land and Building and all attorneys' fees, witness fees,
                  court costs and other expenses of Lessor in connection with
                  any proceeding to contest these amounts.

                  If any taxes, special assessments, fees or other charges are
                  imposed against Lessor by any governmental unit or agency with
                  respect to rentals under this Lease, they shall be included in
                  Tax Costs. Notwithstanding the foregoing provisions of this
                  Section, the following items shall be excluded in computing
                  Tenant's share of Tax Costs applicable to the Premises:



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                  (1)      Any state, local, federal, personal or corporate
                           income tax measured by the income of Landlord, unless
                           and to the extent imposed in lieu of real estate
                           taxes.

                  (2)      Any estate or inheritance taxes, unless and to the
                           extent imposed in lieu of real estate taxes.

                  (3)      Any franchise, succession or transfer taxes.

                  (4)      Interest on taxes or penalties resulting from
                           Lessor's failure to pay taxes.

         (k)      "Lease" means this Lease, all Exhibits attached to this Lease,
                  and all properly executed amendments, modifications and
                  supplements to this Lease.

         (l)      "Section" means a section of this Lease.

         (m)      "Exhibit" means an Exhibit attached to and thereby made a part
                  of this Lease.

         (n)      "Land" means the land described on Exhibit B attached to this
                  Lease.

         (o)      "Taking" means acquisition by a public authority having the
                  power of eminent domain of all or part of the Land or Building
                  by condemnation or conveyance in lieu of condemnation.

         (p)      "Casualty" means a fire, explosion, tornado, or other cause of
                  damage to or destruction of the Building.

         (q)      "Hazardous Materials" means any hazardous or toxic substance,
                  material or waste which is or becomes regulated by any local
                  governmental authority with jurisdiction over the Premises,
                  the State of Minnesota or the United States government
                  including, without limitation, under the Comprehensive
                  Environmental Response, Compensation and Liability Act of
                  1980, as amended, 42 U.S.C. 9601, et seq., the Hazardous
                  Materials Transportation Act, 49 U.S.C. 1801, et seq., and the
                  Resource Conservation and Recovery Act 42 U.S.C. 6901 et seq.,
                  and the regulations promulgated thereunder.

         (r)      "ADA" means the Americans with Disabilities Act.





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2. Premises.


Lessor leases the Premises to Tenant, and Tenant leases the Premises from
Lessor, for the Term, under the terms and conditions of this Lease.

3. Rent.

Tenant will pay the Monthly Rent to Lessor at P.O. Box 73547 Chicago, Illinois
60673-7547, or such other place as Lessor may designate, in advance on or before
the Commencement Date and on or before the first day of each month during the
Term, without demand, deduction or setoff. The Monthly Rent may change as the
Costs are adjusted annually under Sections 4 and 5. Monthly Rent will begin on
the Commencement Date. If the Term begins on a day other than the first day of a
month, the Monthly Rent for that month will be prorated by multiplying the
Monthly Rent by the number of days of that month included in the Term and
dividing the product by the number of days in that month.

Any Monthly Rent or other amounts payable by Tenant to Lessor under this Lease
which are not paid within 10 days after notice from Lessor will bear interest
from the date due to the date paid at the rate of 12% per annum or the maximum
rate of interest permitted by law, whichever is less, and the interest will be
paid to Lessor on demand.

Notwithstanding any other provision of this Lease to the contrary, the Monthly
Rent for the period from the Commencement Date through December 31, 1993 will
not exceed $31,454.00 and no adjustments will be made in Costs for 1993 even if
actual Costs for 1993 exceed estimated Costs for 1993. The provisions of Section
4 will apply, however, to adjustments of Costs for 1994 and subsequent years.

4. Cost Adjustments.

The initial Monthly Rent is based in part upon agreed upon Operating Costs and
Tax Costs. Prior to January 1, 1994, or as soon as reasonably possible
thereafter, Lessor will furnish Tenant with an estimate of the Costs if greater
than the initial Costs, and the Monthly Rent for 1994 and subsequent years will
be increased by 1/12th of the difference between the initial estimate of Costs
and the current estimate.

After the end of 1994 and each subsequent calendar year, including the year in
which the Term expires, Lessor will give Tenant a statement of the actual Costs
for that calendar year. If the actual Costs exceed the estimated Costs for that
year, Tenant will pay the excess to Lessor within 30 days after receiving the
statement. If the actual Costs are less than the estimated Costs for that year,
Lessor will pay the difference to Tenant with the statement. Tenant will have
the right, at its expense, to inspect and audit Lessor's books and records
relating to such Costs and statements.



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If Tenant does not give Lessor written notice within one year after receiving
Lessor's statement that Tenant disagrees with the statement and specifying the
amounts in dispute, Tenant will be deemed to have waived the right to contest
the statement. Tenant will file no petition in Tax Court regarding the Tax Costs
without Lessor's prior written consent. If Lessor contests Tax Costs and
receives a refund or incurs additional Tax Costs after adjustments for actual
Tax Costs have been made, the actual Tax Costs will be corrected accordingly and
the appropriate adjustment will be made between Lessor and Tenant. The portion
of Costs to be paid by Tenant for the years in which the Term begins and ends
will be prorated by multiplying the actual Costs by a fraction, the numerator of
which is the number of days of that year in the Term and the denominator of
which is 365.

5. Cost Computations and Allocations.

Lessor will in its reasonable discretion, in accordance with generally accepted
accounting principles and industry standards, determine the methods of computing
and allocating Costs to the Land and the Building.

6. Fiscal Year.

The year used to determine Costs may be changed to a different 12-month period
designated by Lessor. If the calendar year is changed to a fiscal year, or if a
fiscal year is changed to a different fiscal year, prorations will be made for
the estimated Costs and the actual Costs so that the same time period is used to
determine each and so that Costs are not included in more than one time period.

7. Possession.

If any portion of the Premises is ready for occupancy before the Commencement
Date, Tenant will have the right of access to and occupancy of such portion of
the Premises prior to the Commencement Date without the payment of Monthly Rent
for such period, but all other provisions of this Lease will be applicable
during that period.

If Lessor is delayed in delivering possession of all or any portion of the
Premises to Tenant on the Commencement Date, Tenant will take possession of the
Premises on the date when Lessor delivers possession of all of the Premises,
which date will then become the Commencement Date, and the last day of the term
will be extended so that the length of the Term remains the same. If the
extended Term would end on a day other than the last day of a month, the Term
will be further extended to the last day of the month in which the Term ends.

This Lease will not be void or voidable and Lessor will not be liable to Tenant
for any loss or damage resulting from any delay in delivering possession of the




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Premises to Tenant, but unless the delay is principally caused by or
attributable to Tenant, its employees, agents or contractors, no Monthly Rent
will be due for the period prior to the date Lessor delivers possession of the
Premises, unless Tenant elects to take possession of a portion of the Premises,
in which case Monthly Rent will be due for the portion of the Premises taken.
Tenant's occupancy of the Premises will constitute Tenant's acceptance of the
Premises, except for latent defects and matters which are expressly stated in
this Lease to be the obligation of Lessor.

If Tenant is not in default beyond any applicable cure periods in the payment of
the Monthly Rent and other charges or in material default beyond any cure
periods in the performance of any of Tenant's other obligations under this
Lease, Tenant will have the right to peacefully have, hold and enjoy the
Premises in accordance with the terms of this Lease.


8. Use.

Tenant will use the Premises for business and administrative offices and uses
normally and customarily related to such office uses, and for no other purposes.
Tenant will not commit or permit any act or omission which results in the
violation of any applicable law or governmental regulation relating to the
Building. Tenant will not permit any conduct or condition which may unduly
disturb or endanger the public or the occupants of other buildings based upon
usual and customary standards of use and occupancy for buildings of the type and
location of the Building.

Tenant agrees to the following with respect to any and all Hazardous Materials
used or stored in the Premises, or disposed of from the Premises:

         (a)      Except as provided in this Section, Tenant shall not bring any
                  Hazardous Materials into the Premises or cause the existence
                  of any Hazardous Materials on or in the Premises. Tenant may
                  use those Hazardous Materials customarily kept and used in a
                  typical business office, but only so long as the use, storage
                  and disposal thereof is in strict compliance with all
                  applicable environmental laws and regulations. Tenant may
                  permit the presence of those Hazardous Materials whose
                  existence is not caused by Tenant. If Tenant discovers the
                  presence of any Hazardous Materials on or in the Premises, the
                  Building, or the Land which is contrary to any applicable
                  environmental regulation, Tenant shall promptly give Lessor
                  notice thereof. If the existence of Hazardous Materials is
                  caused by Tenant, Tenant shall remove such Hazardous Materials
                  and dispose of them as required by any applicable
                  environmental regulation. If any governmental authority shall
                  require any remedial action or other




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                  response with respect to the Premises, the Building, or the
                  Land as the result of any Hazardous Materials brought into or
                  caused to exist by Tenant on or in the Premises, the Building,
                  or the Land, Tenant shall notify Lessor of such action or
                  response and shall, with the prior written approval of Lessor,
                  which shall not be unreasonably withheld, be responsible for
                  satisfying the requirements of said response or remedial
                  action to the satisfaction of the applicable governmental
                  authority.

         (b)      Tenant agrees to indemnify, defend and hold Lessor and its
                  agents, affiliates, parent, officers, directors and employees
                  (the "Tenant Indemnitees") harmless from any and all claims,
                  causes of action, damages, penalties and costs (including
                  reasonable attorneys' fees, consultant fees and related
                  expenses) which may be asserted against or incurred by Lessor
                  resulting from: the presence of any Hazardous Materials on or
                  in the Premises, the Building, or the Land, to the extent
                  caused by Tenant; any violation or alleged violation of any
                  applicable environmental regulation to the extent caused by
                  Tenant; or Tenant's failure to properly dispose of any
                  Hazardous Materials in accordance with this Lease. This
                  indemnity includes, but is not limited to, proceedings or
                  actions commenced by any governmental authority. Tenant shall
                  indemnify Lessor against all such reasonable expenses incurred
                  by Lessor pursuant to this Section as they are incurred,
                  rather than waiting for the ultimate outcome of the litigation
                  or administrative proceeding.

         (c)      Lessor agrees to indemnify, defend and hold Tenant and its
                  agents, affiliates, parent corporations, officers, directors
                  and employees (the "Lessor Indemnitees") harmless from any and
                  all claims, causes of action, damages, penalties and costs
                  (including reasonable attorneys' fees, consultant fees and
                  related expenses) which may be asserted against or incurred by
                  Tenant resulting from: the presence of any Hazardous Materials
                  on or in the Premises, the Building, or the Land, to the
                  extent caused by Lessor; any violation or alleged violation of
                  any applicable environmental regulation to the extent caused
                  by Lessor; or Lessor's failure to properly dispose of any
                  Hazardous Materials in accordance with this Lease. This
                  indemnity includes, but is not limited to, proceedings or
                  actions commenced by any governmental authority. Lessor shall
                  indemnify Tenant against all such reasonable expenses incurred
                  by Tenant pursuant to this Section as they are incurred,
                  rather than waiting for the ultimate outcome of the litigation
                  or administrative proceeding.



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         (d)      The foregoing covenants and indemnifications shall be deemed
                  continuing covenants and indemnifications for the benefit of
                  Lessor and the other Tenant Indemnitees, and Tenant and the
                  other Lessor Indemnitees, and their respective successors and
                  assigns, and shall survive the expiration or termination of
                  this Lease.

9. Care of Premises.

Tenant will keep the Premises and the fixtures and equipment in the Premises in
as good condition and repair as they were in at the time possession of the
Premises is tendered to Tenant, except for ordinary wear and damage from fire or
other casualty beyond Tenant's control. If Tenant fails to do so within 30 days
after notice from Lessor (or such longer period as may be reasonably necessary
if Tenant has initiated action and is diligently proceeding), Lessor may enter
the Premises to perform the maintenance and repairs and charge the reasonable
costs thereof to Tenant, together with interest as provided in Section 3.

10. Building Rules.

Rules and Regulations for the Premises and the Building in effect on the date of
this Lease are attached as Exhibit C. Lessor will have the right to adopt
different or additional reasonable rules and regulations which do not materially
affect the rights of Tenant under this Lease, and to rescind or amend in writing
the attached rules and regulations from time to time. Tenant will abide by the
rules and regulations then in force and will cause Tenant's employees to observe
and comply with them.

11. Compliance with Laws.

Tenant will, at its expense, promptly comply with all laws, ordinances, rules,
orders, regulations and other requirements of governmental authorities now or
subsequently pertaining to the Premises, but Tenant will have no obligation to
make any capital improvements or repairs necessary because of any failure of the
Building to comply on the date of this Lease. Tenant will pay any taxes or other
charges by any governmental authority on Tenant's property or trade fixtures in
the Premises or relating to Tenant's use of the Premises.

Notwithstanding the foregoing, Lessor will be responsible for ADA compliance for
the Land, access points to the Building, existing stairwells, and restrooms
within the Building. Tenant will be responsible for all other ADA compliance
within the Premises.

Lessor represents and warrants that it has received no notice from any
governmental authority with jurisdiction over the Land or Building of any
uncured



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violation by Lessor, the Premises or the Building of any applicable law,
ordinance, rule, order, regulation or other requirement.

If Lessor or Tenant receives notice after the date of this Lease from a
governmental authority with jurisdiction over the Land or Building of any
uncured violation by Lessor, the Premises or the Building of any applicable law,
ordinance, rule, order, regulation or other requirement, or requirement for
repairs or improvements, and the condition constituting the violation giving
rise to the requirement existed on the date of this Lease, then Tenant will have
no obligation to correct the violation or complete the repairs or improvements
at its expense or to pay or share in the cost thereof. In any such case, Lessor
will be responsible for the correction of the violation or completion of the
repairs or improvements at Lessor's cost and expense if: (i) the correction,
repairs or improvements are required after Lessor has had a reasonable
opportunity to contest the requirement or alleged violation; (ii) the
requirement or alleged violation is not the result of Tenant's specific use of
the Premises; and (iii) the violation or any action by the governmental
authority adversely affects Tenant's ability to use or occupy the Premises.

If Lessor or Tenant receives notice after the date of this Lease from a
governmental authority with jurisdiction over the Land or Building of any
uncured violation by Tenant, the Premises or the Building of any applicable law,
ordinance, rule, order, regulation or other requirement, or requirement for
repairs or improvements, and the condition constituting the violation or giving
rise to the requirement arose after the date of this Lease, or is a result of
Tenant's specific use of the Premises, then, except to the extent limited in the
first paragraph of this Section, Tenant will correct the violation or complete
the repairs or improvements at its expense if the correction, repairs or
improvements are required after Tenant has had a reasonable opportunity to
contest the requirement or alleged violation.

The provisions of this Section 11 do not apply to Hazardous Materials. The
obligations of the parties with respect to Hazardous Materials are covered in
Sections 8 and 30 of this Lease.

12. Signs.

Except for signs approved in advance by Lessor in writing, which approval will
not be unreasonably withheld, Tenant will not place or permit any other signs on
the exterior or windows of the Building, or within the Premises if visible from
the exterior of the Building, except lettering and numerals for identification
purposes on or near doorways as approved in advance by Lessor.

Lessor agrees that Tenant will be entitled to identification signage on the
exterior of the Building, subject to Lessor's approval of the size, location,
type and design of the sign, and subject to compliance with all applicable laws,
ordinances and regulations.

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Lessor agrees that it will pay the cost of one exterior sign approved by Lessor
up to a maximum payment by Lessor of $6,000.00.

13. Construction of Tenant Improvements; Alterations.

Tenant will prepare plans and specifications ("Plans") for Tenant's improvements
within the Premises (the "Tenant Improvements") and will submit the Plans for
all Tenant Improvements to Lessor for approval no later than July 10, 1993.
Tenant will utilize Weld Ransom to conduct Tenant's space planning and plan
review, and for the preparation of all Plans. Tenant will be responsible for the
costs of all such services, but Lessor will contribute an allowance for such
costs up to $56,665.00.

Lessor will then enter into contracts to construct the Tenant Improvements
according to the Plans prepared by Tenant and approved by Lessor. Except for the
Tenant Improvements, Tenant accepts the Premises in their present condition
(except for latent defects and matters which are expressly stated in this Lease
to be the obligation of Lessor) and Lessor will have no obligation to do any
redecorating or remodeling or to make any repairs or alterations other than the
Tenant Improvements.

Tenant will be responsible for all costs of the Tenant Improvements, but Lessor
will contribute an improvement allowance against the cost of the work up to
$453,320.00 ("Improvement Allowance"). Tenant will pay to Lessor upon request
the amount by which the cost of the work exceeds the Improvement Allowance. If
the Improvement Allowance exceeds the total costs of the Tenant Improvements,
Lessor will pay the excess to Tenant after final completion of the Tenant
Improvements and occupancy of the Premises by Tenant.

As an alternative to the construction by Lessor of the Tenant Improvements,
Tenant may construct the Tenant Improvements. Such construction of the Tenant
Improvements by Tenant shall be subject to all of the requirements of this
Section set forth below concerning alterations by Tenant, including but not
limited to the requirement that Tenant first obtain Lessor's prior written
approval of any contractor or subcontractor who is to perform work on the
Premises at Tenant's request, which approval shall not unreasonably be withheld.
Lessor hereby approves CB Commercial Real Estate Group as a construction manager
for the construction of the Tenant Improvements. Upon final completion of the
Tenant Improvements and the submission of final lien waivers for all of such
work to Lessor, Lessor will reimburse Tenant for the cost to Tenant of the
Tenant Improvements up to the amount of the Improvement Allowance. Thirty days
after the commencement by Tenant of the construction of the Tenant Improvements,
Tenant may apply for a partial disbursement of the Improvement Allowance. Such
partial disbursement shall be limited to reimbursement to Tenant for work
completed through the thirtieth day of construction which has actually been paid
for

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by Tenant. In order to be eligible for such partial disbursement, Tenant must
submit to Lessor a sworn construction statement with respect to all work through
the thirtieth day of construction, proof that all work through the thirtieth day
of construction has actually been paid for, and lien waivers for all work
through the thirtieth day of construction. In order to be eligible for
reimbursement, all work must be in substantial compliance with the Plans
approved by Lessor and otherwise in accordance with the terms and conditions of
this Lease. Provided that all of the foregoing conditions are satisfied, Lessor
shall make the partial disbursement within fourteen business days after Tenant
makes application to Lessor for the partial disbursement. The amount disbursed
to Tenant upon final completion of the Tenant Improvements shall be reduced by
the amount of any earlier partial disbursement.

In the case of any failure of Lessor to make any payment due Tenant under this
Section 13, if Lessor fails to pay the same within 10 days after written demand
by Tenant to Lessor, Tenant shall have the right to deduct the amount past due
from Lessor under this Section, without liability for forfeiture, as an offset
against Monthly Rent.

Tenant will not make any alterations, additions or improvements in or to the
Premises without first obtaining the written approval of Lessor, which approval
shall not unreasonably be withheld. Tenant will get Lessor's prior written
approval of any contractor or subcontractor who is to perform work on the
Premises at Tenant's request, which approval shall not unreasonably be withheld.
Lessor may require Tenant to post a bond, cash or other security to protect the
Premises from mechanic's liens. All alterations by Tenant will be constructed
with new materials unless the materials are already in the Premises, in a good
and workmanlike manner, and in substantial compliance with the plans and
specifications approved by Lessor and all applicable laws, ordinances, rules,
orders, regulations, or other requirements of governmental authorities. Tenant
will pay for any labor, services, materials, supplies or equipment properly
furnished or alleged to have been furnished to Tenant in or about the Premises.
Tenant will pay and discharge any mechanic's, materialmen's or other lien
against the Premises resulting from Tenant's failure to make such payment or
alleged failure to make such payment, or will contest the lien and deposit with
Lessor cash equal to the amount of the lien plus Lessor's reasonable estimate of
any additional costs to remove the lien. If the lien is reduced to final
judgment, Tenant will discharge the judgment and Lessor will return the cash
deposited by Tenant. Lessor may post notices of nonresponsibility on the
Premises as provided by law.

All alterations, additions and improvements to the Premises made at Lessor's or
Tenant's expense, except movable office furniture and Tenant's movable trade
fixtures and equipment, will become the property of Lessor upon installation and

                                       14


<PAGE>   15




will be surrendered with the Premises upon termination of this Lease, except as
otherwise agreed in writing by Lessor and Tenant.

14. Utilities and Services.

Lessor will supply reasonable janitor service, heat and air conditioning
appropriate to the season (with temperatures in the range of 68 to 75 degrees),
and water, elevator service, ventilation and electricity in reasonable amounts
for the uses herein permitted. Lessor will provide security services as
requested by Tenant and approved by Lessor, and Lessor's approval of the
services will not be unreasonably withheld. Janitorial services will be provided
by Lessor according to the specifications attached as Exhibit E. The cost of all
such services will be a part of the Operating Costs except to the extent the
costs are paid by Tenant directly. Lessor will not be liable for any loss or
damage resulting from any temporary interruption of these services due to
repairs, alterations or improvements, or any variation, interruption or failure
of these services due to governmental controls, unavailability of energy, or any
other cause beyond Lessor's control. No such interruption or failure of these
services will be deemed as an eviction of Tenant or will relieve Tenant from any
of its obligations under this Lease.

If services are interrupted for a period of five consecutive days and all or a
portion of the Premises are untenantable because of a lack of services which are
in Lessor's control to provide or restore, the Monthly Rent will abate for the
period the Premises are untenantable in proportion to the portion of the
Premises which are untenantable.

15. Entry by Lessor.

Lessor and its agents and contractors and mortgagees will have the right to
enter the Premises at reasonable times after reasonable notice to Lessor (except
in cases of emergency) for inspecting, cleaning, repairing, or exhibiting the
Premises, but Lessor will have no obligation to make repairs, alterations or
improvements except as expressly provided in this Lease.

16. Subordination.

Lessor represents and warrants to Tenant that Lessor is the fee owner of the
Premises and that the total indebtedness secured by any and all mortgages
encumbering the Land and Building does not exceed $700,000. At the request of
any mortgagee or ground lessor, this Lease will be subject and subordinate to
any mortgage or ground lease which may now or hereafter encumber the Building,
and Tenant will execute, acknowledge and deliver to Lessor any reasonable
document requested by Lessor to evidence the subordination; provided, however,
that any such subordination is on the condition that Tenant's rights under this
Lease will not


                                       15




<PAGE>   16






be affected by the mortgagee's or ground lessor's rights thereunder so long as
Tenant is not in default under this Lease. If the interest of Lessor is
transferred to any party by reason of foreclosure of a mortgage or cancellation
of a ground lease, or by delivery of a deed in lieu of foreclosure or
cancellation, Tenant will immediately and automatically attorn to such party
upon 10 days' notice to Tenant. Tenant agrees that upon notification by Lessor
or any mortgagee or ground lessor of the election of a mortgagee or ground
lessor to subordinate its interest in the Premises to this Lease, this Lease
will become prior to the mortgage or ground lease.

17. Estoppel Certificates.

Within 10 days after written request from Lessor, Tenant will execute,
acknowledge and deliver to Lessor a document furnished by Lessor, which document
may be relied upon by Lessor and any prospective purchaser or mortgagee of the
Building, stating (a) that this Lease is unmodified and is in full force and
effect (or if modified, that the Lease is in full force and effect as modified
and stating the modifications), (b) the dates to which rent and other charges
have been paid, (c) the current Monthly Rent, (d) the dates on which the Term
begins and ends, (e) that Tenant has accepted the Premises and is in possession,
(f) that Lessor is not to Tenant's knowledge in default under this Lease, or, if
Lessor is in default, specifying any such default, and (g) including such other
information as the prospective purchaser or mortgagee may require.

18. Waiver of Claims and Assumption of Risks.

Lessor and Tenant release each other from any liability for loss or damage by
fire or other casualty coverable by a standard form of "all risk" insurance
policy, whether or not the loss or damage resulted from the negligence of the
other, its agents or employees. The releases in this Section will be effective
whether or not the loss was actually covered by insurance. Tenant assumes all
risk of loss or damage of Tenant's property within the Premises, including any
loss or damage caused by water leakage, fire, windstorm, explosion, theft, or
other cause. Lessor will not be liable to Tenant, or its employees, for loss of
or damage to any property in the Premises.

19. Indemnification.

Tenant will indemnify Lessor and the Tenant Indemnitees (as defined in Section
8) against all claims, demands and actions, and all related costs and expenses
(including reasonable attorneys' fees) for injury, death, disability or illness
of any person, or damage to property, occurring in the Premises or in or about
the Land or Building or arising out of Tenant's use of the Premises, except to
the extent caused by the Lessor's failure to perform it's obligations under this
Lease or the wrongful act of Lessor or someone acting on its behalf.



                                       16


<PAGE>   17


Lessor will indemnify Tenant and the Lessor Indemnitees (as defined in Section
8) against all claims, demands and actions, and all related costs and expenses
(including reasonable attorneys' fees) for injury, death, disability or illness
of any person, or damage to property, occurring in the Premises or in or about
the Land or Building or arising out of the Lessor's failure to perform it's
obligations under this Lease or the wrongful act of Lessor or someone acting on
its behalf.


20. Insurance.

Tenant will keep public liability insurance or self-insurance in force at its
expense by an insurer and policy acceptable to Lessor in its reasonable opinion.
The policy or self-insurance will provide coverage for limits of at least
$1,000,000 for bodily injuries or death of one or more persons and at least
$100,000 for property damage. Tenant will carry fire and "all risk" coverage
insurance for Tenant's property and improvements in the Premises. Prior to
Tenant's occupancy of the Premises, Tenant will deliver to Lessor the liability
and casualty certificates showing this coverage to be in effect. The insurance
will provide that Lessor will be notified in writing 30 days prior to
cancellation of, material change in, or failure to renew, the insurance.

21. Assignment and Subletting.

Tenant shall have the right to assign this Lease or sublet the Premises, subject
to the terms and conditions of this Section, and except in the case of an
Affiliate (as defined below) subject to Lessor's prior written consent, which
consent will not be unreasonably withheld.

Except with respect to any assignment or subletting to an Affiliate (as defined
below), Tenant shall promptly pay to Lessor, as additional rent hereunder,
"Tenant's Profit" (as defined below) from such assignment or subletting.
Tenant's Profit shall be paid to Lessor as and when received by Tenant.

For purposes of this Section, "Tenant's Profit" shall mean any rent or other
payments pursuant to any sublease which exceed the amounts payable under this
Lease, and all other consideration paid or to be paid by reason of any
assignment or sublease, after deducting therefrom the reasonable out-of-pocket
costs and expenses incurred by Tenant in connection with such assignment or
sublease, including, without limitation brokerage commissions, attorneys' fees,
tenant improvements and marketing costs.

No assignee or subtenant will use the Premises for any purpose not permitted
under this Lease or in any other way contrary to the provisions of this Lease.



                                       17



<PAGE>   18




Upon at least 30 days' prior written notice by Tenant to Lessor, Tenant will
have the right to assign this Lease, or sublet all or part of the Premises, to a
corporation which controls, is controlled by, or is under common control with,
Tenant ("Affiliate"), if (a) after the assignment or sublease the parties
maintain the same control relationship, and (b) Tenant provides Lessor with a
copy of the proposed assignment or sublease with the notice.

If Lessor consents to one or more assignments or subleases, or if an assignment
or sublease occurs as permitted in this Section without the Lessor's consent,
Tenant will still remain liable for all obligations of the Tenant under this
Lease.

Lessor's interest in this Lease will be freely assignable and the obligations of
the Lessor arising or accruing under this Lease after an assignment will be
enforceable only against the assignee.

22. Damage or Destruction.

If the Premises or Building is damaged by Casualty, the damage (excluding damage
to improvements paid for by Tenant or trade fixtures, equipment or personal
property of Tenant) will be repaired by Lessor at its expense to a condition as
near as reasonably possible to the condition prior to the Casualty, but if more
than 25% of the total rentable area of the Building is rendered untenantable,
Lessor may terminate this Lease as of the date of the Casualty by giving written
notice to Tenant within 30 days after the Casualty. If this Lease is not
terminated, Lessor will begin repairs within 90 days after the Casualty and
complete the repairs within a reasonable time, not to exceed 180 days, subject
to acts of God, strikes and other matters not within the control of Lessor. If
Lessor fails to begin and proceed with repairs as required, Tenant may give
Lessor notice to do so. If Lessor has not begun the repairs within 30 days after
Tenant's notice, Tenant may terminate this Lease by written notice to Lessor
within 15 days after expiration of the 30-day period. If this Lease is
terminated because of the Casualty, rents and other payments will be prorated as
of the date of the Casualty and will be proportionately refunded to Tenant or
paid to Lessor, as the case may be. During any period in which the Premises or
any portion of the Premises is made untenantable as a result of the Casualty,
the Monthly Rent will be abated for the period of time untenantable in
proportion to the square foot area untenantable.

23. Eminent Domain.

If there is a Taking of 25% or more of the Premises, either party may terminate
this Lease as of the date the public authority takes possession, by written
notice to the other party within 15 days after the Taking. If this Lease is so
terminated, any rents and other payments will be prorated as of the termination
and will be proportionately refunded to Tenant, or paid to Lessor, as the case
may be. All

                                       18


<PAGE>   19






damages, awards and payments for any Taking will belong to Lessor irrespective
of the basis upon which they were made or awarded, except that Tenant will be
entitled to any amounts specifically awarded for Tenant's trade fixtures or
equipment or as a relocation payment or allowance. If this Lease is not
terminated as a result of the Taking, Lessor will restore the remainder of the
Premises to a condition as near as reasonably possible to the condition prior to
the Taking, the rent will be abated for the period of time the space is
untenantable in proportion to the square foot area untenantable and this Lease
will be amended appropriately to reflect the deletion of the space taken.

24. Defaults.

If (a) Tenant defaults in the payment of rent or other amounts under this Lease
and the default continues for 10 days after written notice by Lessor to Tenant,
(b) Tenant defaults in any other obligation under this Lease and the default
continues for 30 days after written notice by Lessor to Tenant, (c) any
proceeding is begun by or against Tenant to subject the assets of Tenant to any
bankruptcy or insolvency law or for an appointment of a receiver of Tenant or
for any of Tenant's assets, or (d) Tenant makes a general assignment of Tenant's
assets for the benefit of creditors, then Lessor may, with or without
terminating this Lease, cure the default and charge Tenant all costs and
expenses of doing so, and Lessor also may reenter the Premises, remove all
persons and property, and regain possession of the Premises, without waiver or
loss of any of Lessor's rights under this Lease, including Lessor's right to
payment of Monthly Rent. Lessor also may terminate this Lease as to all future
rights of Tenant, without terminating Lessor's right to payment of Monthly Rent
and other charges due under this Lease.

If this Lease is terminated under this Section, Tenant promises and agrees to
pay all Monthly Rent and other charges due for the remainder of the original
Term, and all reasonable attorneys' fees and other expenses. If Tenant defaults
in any of its obligations under this Lease, it will promptly pay all reasonable
costs (including attorneys' fees) of enforcing Tenant's obligations, whether or
not this Lease is terminated and whether or not suit is brought. No right or
remedy will preclude any other right or remedy, no right or remedy will be
exclusive of or dependent upon any other right or remedy, and any right or
remedy may be exercised independently or in combination.

If Tenant is in default and notice of termination of Tenant's right to
possession has been mailed to Tenant at the Premises and it appears in Lessor's
reasonable judgment that Tenant has abandoned or vacated the Premises, Lessor
may reenter the Premises and retake possession without legal action, without
relieving Tenant of the obligation to pay Monthly Rent or any other obligations
under this Lease, and without any liability to Tenant for re-entry removal of
Tenant's property.


                                       19


<PAGE>   20






Notwithstanding any other provision of this Section 24, in no event will Lessor
by its action or inaction, prevent Tenant from mitigating any damages which
Lessor or Tenant may otherwise incur with respect to a default by Tenant under
this Lease.

Lessor will be deemed in default under this Lease if it fails or refuses to
perform any provisions of this Lease it is obligated to perform and such failure
or refusal is not cured within 30 days after written notice thereof is given by
Tenant to Lessor. If the default cannot reasonably be cured within 30 days,
Lessor will not be in default if Lessor commences to cure the default within the
30-day period and diligently proceeds with its efforts to cure the default. In
the event of a default by Lessor, Tenant will be entitled to assert all remedies
available at law or in equity, but Tenant will in no case be entitled to offset
any claims or amounts against the Monthly Rent.


25. Waiver of Lease Provisions.

No waiver of any provision of this Lease will be deemed a waiver of any other
provision or a waiver of that same provision on a subsequent occasion. The
receipt of rent by Lessor with knowledge of a default under this Lease by Tenant
will not be deemed a waiver of the default. Each of the Lessor and Tenant will
not be deemed to have waived any provision of this Lease by any action or
inaction and no waiver will be effective unless it is done by expressed written
agreement signed by the party waiving the provision. Any payment by Tenant and
acceptance by Lessor of a lesser amount than the full amount of all Monthly Rent
and other charges then due will be applied to the earliest amounts due. No
endorsement or statement on any check or letter for payment of rent or other
amount will be deemed an accord and satisfaction, and Lessor may accept such
check or payment without prejudice to its right to recover the balance of any
rent or other amount or to pursue any other remedy provided in this Lease. No
acceptance of payment of less than the full amount due will be deemed a waiver
of the right to the full amount due together with any interest and service
charges.

26. Return of Possession to Lessor.

On expiration of the Term or sooner termination of this Lease, Tenant will
return possession of the Premises to Lessor, without notice from Lessor, in good
order and condition, except for ordinary wear and damage, destruction or
conditions Tenant is not required to remedy under this Lease. If Tenant does not
return possession of the Premises to Lessor, Tenant will pay Lessor all
resulting damages Lessor may suffer and will indemnify Lessor against all claims
made by any new tenant of all or any part of the Premises. Tenant will give
Lessor all keys for the Premises and will inform Lessor of combinations on any
locks and safes on the Premises. Any property left in the Premises after
expiration or termination of this Lease or after the



                                       20


<PAGE>   21


Premises have been vacated by Tenant will after at least 5 days' notice thereof
from Lessor become the property of Lessor to dispose of as Lessor chooses.

27. Holding Over.

If Tenant remains in possession of the Premises after expiration of the Term
without a new lease, it may do so only with written consent by Lessor, and any
such holding over will be from month-to-month subject to all the same provisions
of this Lease, except that the Monthly Base Rent will be the Monthly Base Rent
stated in Lessor's consent if a new Monthly Base Rent is stated, or 150% the
Monthly Base Rent under this Lease if no new Monthly Base Rent is stated in
Lessor's consent. Any holding over without Lessor's consent will be at 150% the
Monthly Rent under this Lease. The month-to-month occupancy may be terminated by
Lessor or Tenant on the last day of any month by at least 30 days' prior written
notice to the other.

28. Termination.

If Lessor decides to demolish the Building, it will give Tenant notice as soon
as reasonably possible after the decision has been made, and Lessor will have
the right to terminate this Lease by at least 12 months' prior written notice to
Tenant; provided, however, that such termination will be effective no sooner
than September 30, 2000.

29. Extension Term.

Lessor grants Tenant two options to extend the Term for periods of 60 months
each ("Extension Terms"), subject to the following conditions:

         (a)      At the time Tenant exercises the option, Tenant is not in
                  default under this Lease.

         (b)      Tenant gives Lessor at least 9 months' prior written notice of
                  Tenant's election to extend the Term.

         (c)      Each Extension Term will be on the same terms, covenants and
                  conditions provided during the initial Term except that there
                  will be no further option to extend the Term after the second
                  Extension Term, and any allowances or other concessions will
                  be taken into account in determining the Monthly Base Rent,
                  which will be the greater of the Monthly Base Rent for the
                  final month preceding the extension, or a monthly base rent
                  based upon 90% of the fair rental value ("Fair Rental Value")
                  of the Premises at the commencement of the Extension Term,
                  considering all provisions of this Lease and the rates for
                  comparable


                                       21


<PAGE>   22




                  suburban office space if leased subject to the same provisions
                  as this lease, and considering any free rent, tenant
                  improvement allowances and other inducements which are
                  typically being offered and adjusting for those inducements
                  which are or are not included, and assuming a willing lessor
                  and a willing tenant each of which is under no obligation to
                  lease the space.

                  The Fair Rental Value shall be determined as follows: Within
                  30 days after Lessor receives notice from Tenant regarding
                  Tenant's election to exercise the Extension Term, Lessor will
                  give notice to Tenant of its determination of the Fair Rental
                  Value of the Premises, and Lessor's determination will
                  constitute the Fair Rental Value unless Tenant objects in
                  writing within 30 days after Tenant's receipt of Lessor's
                  determination. If Tenant so objects, and the parties are
                  unable to agree upon the Fair Rental Value within 30 days
                  after the Tenant's objection, then by written notice to Lessor
                  within 10 days thereafter Tenant may request arbitration of
                  the Fair Rental Value under this paragraph. If Tenant does not
                  give such notice requesting arbitration, Tenant's exercise of
                  the option will be deemed rescinded. If arbitration is
                  requested by Tenant, the Fair Rental Value will be determined
                  by appraisal within 90 days after Tenant's request by a board
                  of appraisers consisting of three reputable real estate
                  appraisers (each an "Expert"), each of whom is a member of the
                  American Institute of Real Estate Appraisers with the
                  designation of "MAI." One Expert will be appointed by Tenant,
                  and the second Expert will be appointed by Lessor. The third
                  Expert will be appointed by the first two Experts. If the
                  first two Experts are unable to agree on a third Expert within
                  10 days after the appointment of the second Expert, or if
                  either party refuses or neglects to appoint an Expert as
                  herein provided within 10 days after the appointment of the
                  first Expert, then the third Expert or the second Expert,
                  whose appointment was not made as provided above, may be
                  appointed by any judge of the Hennepin County District Court.
                  If determinations of at least two of the Experts are identical
                  in amount, that amount will be determined to be the Fair
                  Rental Value. If the determinations of all three Experts are
                  different in amount, the highest appraised value will be
                  averaged with the middle value (that average being referred to
                  as "Sum A"). The lowest appraised value will be averaged with
                  the middle value (that average being referred to as "Sum B"),
                  and the Fair Rental Value will be determined as follows: (i)
                  if neither Sum A nor Sum B differs from the middle appraised
                  value by more than 10% of the middle appraised value, then the
                  Fair Rental Value will be the average of the three appraisals,
                  (ii) if either Sum A or Sum B (but not both) differs from the
                  middle appraised value by more than 10% of the middle
                  appraised value, then the Fair


                                       22




<PAGE>   23






                  Rental Value will be the average of the middle appraised value
                  and the appraised value closer in amount to the middle
                  appraised value, and (iii) if both Sum A and Sum B differ from
                  the middle appraised value by more than 10% of the middle
                  appraised value, then the Fair Rental Value will be equal to
                  the middle appraised value. Written notice of the Fair Rental
                  Value as duly determined in accordance with this Section shall
                  be promptly given to Lessor and Tenant and will be binding and
                  conclusive on them. Each party will bear its own expenses in
                  connection with the board proceeding (including the Expert
                  appointed by it), and the fees of the third Expert will be
                  borne equally. If, for any reason, the Fair Rental Value has
                  not been determined at the time of the commencement of the
                  Renewal Period, then the Fair Rental Value will be the amount
                  set forth in Lessor's determination, and if the determination
                  of the Experts as provided above indicates that a lesser or
                  greater amount should have been paid than that which was
                  actually paid, a proper adjustment will be made in a payment
                  from Lessor to Tenant, or Tenant to Lessor, as the case may
                  be, together with interest on the amount of the adjustment at
                  the rate of 10% per annum.

         (d)      On written request by Tenant no more than 30 days prior to the
                  date Tenant's notice to extend must be given, Lessor will
                  provide Tenant with the monthly base rental rate it would
                  charge for the Premises under paragraph (c) above.

         (e)      At the request of either party, Lessor and Tenant will execute
                  and deliver appropriate documents covering extension of the
                  Term, the new Monthly Base Rent and other terms of this Lease
                  during the extended Term.

         (f)      The rights of Tenant under this Section will not be severed
                  from this Lease or separately sold, assigned or transferred,
                  and will expire on the expiration or earlier termination of
                  this Lease.

         (g)      If Lessor gives Tenant the notice of Lessor's intention to
                  demolish the Building, as provided for in Section 28, the
                  provisions of this Section will be null and void as to any
                  extension of the Term not yet in effect.

30. Environmental Matters.

If in the construction of the Tenant Improvements, the parties, or the
contractor constructing the Tenant Improvements, encounter any exposed
accessible asbestos, then Lessor shall, at its expense, cause the asbestos to be
removed in accordance with



                                       23


<PAGE>   24




applicable federal and state laws and regulations, and no part of the
Improvement Allowance will be applied to the cost of such removal.

Lessor represents and warrants that to the actual knowledge of the current
officers of Lessor, without any testing, environmental audits, assessments,
evaluations, inspections, reviews or other inquiries or investigations:

         (a)      The soil and ground water on or under the Premises are free of
                  Hazardous Materials which exist in violation of any applicable
                  law, ordinance or regulation, and there have been no disposal,
                  releases or threatened releases of Hazardous Materials on,
                  from or under the Premises in violation of any applicable law,
                  ordinance or regulation.

         (b)      The Premise are free of any Hazardous Materials existing in
                  violation of any applicable law, ordinance or regulation.

         (c)      The Premise are free of any asbestos and PCB's, except for
                  floor tile containing asbestos.

         (d)      Any handling, transportation, storage, treatment or use of
                  Hazardous Materials that has occurred on the Premises has been
                  in compliance with all applicable federal, state or local
                  laws, ordinances and regulations.

         (e)      There are no underground storage tanks on the Premises.

For purposes of this Section, the term "knowledge" will not be deemed to include
constructive knowledge or knowledge by attribution.

31. Lessor's Work.

Lessor will, at its sole cost and expense complete the work and improvements
described on Exhibit D attached hereto. No portion of the Improvement Allowance
will be applied to the cost of such work and improvements.

32. Parking.

Tenant will be entitled to the exclusive use of all parking areas on the Land.
Lessor will grant no parking rights, privileges or easements to any other
parties for any of the parking areas on the Land, but Lessor will have no
obligation to police such parking areas to ensure that they are not being used
by unauthorized persons.




                                       24


<PAGE>   25






33. Expansion.


Lessor will give Tenant written notice of the availability of any portion of the
space on the second floor of the building known and referred to as Norman Center
I prior to the date when that space (the "Offer Space") is available to Lessor
for leasing and Network Communications Corporation ("NCC"), or the successor or
assigns of NCC, under NCC'S lease of space in said building has not elected to
lease the space. The notice will state the Monthly Base Rent for the Offer
Space. Tenant will have the right to lease the Offer Space under this Section
if:

                  (a)      Tenant is not in default under this Lease.

                  (b)      NCC does not elect to exercise its rights to lease
                           any part of the Offer Space.

                  (c)      Tenant delivers to Lessor written notice exercising
                           its right to lease the Offer Space within 10 days
                           after Lessor's notice of availability of the Offer
                           Space.

If Tenant fails to exercise its right to lease the Offer Space, Tenant will have
no further right to lease the Offer Space thereafter.

A lease of space under this Section will contain the following:

                  (1)      Monthly Base Rent will be the amount stated in
                           Lessor's notice of availability of the Offer Space.

                  (2)      Costs will be determined in the manner set forth in
                           this Lease.

                  (3)      The commencement date for the lease will be the later
                           of the date the Offer Space becomes available to
                           Lessor for occupancy or 30 days after notice from
                           Lessor that the Offer Space is available.

                  (4)      The Term will end on the expiration or earlier
                           termination of this Lease, subject to the Extension
                           Terms contained in this Lease.

                  (5)      Tenant will take the space in an "as-is" condition
                           with all improvements to be Tenant's responsibility
                           at Tenant's cost.

                  (6)      There will be no Improvement Allowance, rent
                           abatement, space planning allowance, moving allowance
                           or other concessions.


                                       25




<PAGE>   26



                  (7)      All other terms and conditions will be the same as
                           contained in this Lease.

34. Relocation Allowance.

Within 30 days after Tenant has taken occupancy of the Premises, Lessor will pay
to Tenant a relocation allowance in the amount of $191,631.00, regardless of the
actual costs incurred by Tenant.

35. Antennas.

Tenant will have the right to use the roof of the Building for the installation
and operation of antennas and related facilities ("Antennas"), subject to the
prior written approval of Lessor as to the location, nature, design, appearance
and size of the Antennas. If Antennas are installed by Tenant, Tenant will not
commit or permit any act or omission which results in the violation of any law,
governmental regulation, or insurance policy of Lessor, relating to the
Building. Tenant will not permit any conduct or condition which may unduly
disturb or endanger occupants of any other building.

Any installation of Tenant's Antennas ("Tenant's Work") will be completed by
Tenant, at Tenant's expense, in strict accordance with plans approved in writing
by Lessor, and no modifications, additions or alterations will be made without
Lessor's prior written consent, which consent will not be unreasonably withheld.
Aesthetic concerns will be deemed valid reasons for withholding consent. All
working drawings for Tenant's Work will be prepared by Tenant at Tenant's
expense and will be submitted to Lessor for approval. All Tenant's Work will be
done in a good and workmanlike manner and as expeditiously as possible. Tenant's
installation and use of the Antennas will be subject to the following (the
"Conditions"):

         (a)      No Antennas may be installed without Lessor's prior written
                  approval. Lessor's approval will not be unreasonably withheld
                  or delayed so long as the work complies with the plans
                  approved by Lessor and Tenant is not in default under this
                  Lease and so long as all other conditions set forth in this
                  Section are met.

         (b)      Tenant will submit the working drawing for the Tenant's Work
                  and the Antennas to Lessor at least 30 days before the date
                  the Tenant's Work is to commence.

         (c)      Tenant will provide Lessor with evidence acceptable to Lessor
                  that the Antennas and their proposed installation comply with
                  all applicable laws, ordinances, rules and regulations, and
                  that Tenant has obtained

                                       26


<PAGE>   27

                  any licenses, permits or other governmental consents or
                  approvals required for the installation or use of the Antennas
                  and the other Tenant's Work.

         (d)      Upon request, Tenant will provide Lessor with evidence
                  acceptable to Lessor that the Antennas are owned or leased by
                  Tenant and that the installation of the Antennas will comply
                  with all provisions of Section 10 of this Lease relating to
                  alterations.

         (e)      Tenant will promptly pay all costs of the Tenant's Work and
                  the Antennas and any construction, installation, repair,
                  maintenance, or governmental approval or licensing costs
                  associated with the Tenant's Work and the Antennas.

         (f)      Tenant will provide Lessor with evidence that the Antennas are
                  insured against fire, theft and other risks normally covered
                  by an "all risk" policy of casualty insurance, and evidence
                  that the Tenant's liability insurance required under Section
                  20 of this Lease, or a separate policy meeting the
                  requirements of Section 20, applies to all of the Antennas and
                  their installation, use, maintenance and repair.

         (g)      Neither the Antennas nor their installation, use, maintenance
                  or repair shall:

                  (1)      be disruptive or disturbing to tenants of any other
                           building by reason of noise, vibration, radio or
                           electromagnetic interference, or similar cause, or to
                           Lessor's operation or maintenance of the Land or
                           Building or other buildings,

                  (2)      be architecturally or aesthetically inharmonious with
                           the Land or Building,

                  (3)      affect the structural or mechanical integrity of the
                           Building or the operation or maintenance of the
                           systems serving the Building or serving other
                           buildings,

                  (4)      increase the insurance costs for the Building (except
                           for costs to be paid solely by Tenant),

                  (5)      endanger the safety or well-being of Lessor, any
                           tenant of any other building, or any employees or
                           invitees of Lessor or any other tenant.




                                       27


<PAGE>   28






         (h)      Tenant agrees to comply with and obtain all necessary
                  approvals, permits, licenses, etc., required by the Federal
                  Communications Commission (the "FCC") and any other
                  governmental authorities asserting jurisdiction over the
                  installation or operation of any of Tenant's Antennas. Tenant
                  warrants, represents and agrees that the installation and
                  operation of the roof installations shall in no way materially
                  interfere with the operation of any other Building system or
                  antenna system(s) presently in operation or in operation in
                  the future in or on the Building and that in the event such
                  interference should occur, Tenant, after having received
                  notice of such interference, will take immediate action to
                  eliminate said interference and restore the proper operation
                  of such system(s) as required by law or directive of the FCC.
                  In the event that Tenant fails to eliminate the interference
                  as required by law or directive of the FCC within a reasonable
                  time, Lessor may, at its discretion, (a) cure such
                  interference and thereafter add the cost and expense incurred
                  by Lessor therefor to the next Monthly Rent to become due and
                  Tenant shall pay said amount as additional Monthly Rent, or
                  (b) treat such failure on the part of Tenant to eliminate said
                  interference, as required by the FCC within the time allotted
                  by the FCC, as a default under this Lease.

                  Tenant agrees to indemnify and hold Lessor harmless from and
                  against any claims and expenses Lessor may incur arising from
                  Tenant's failure to comply with the Conditions or the rules
                  and orders of the FCC with respect to the installation and
                  operation of any of Tenant's antennae or antenna system(s).

36. Brokers.

Lessor and Tenant represent and warrant one to another that except for CB
Commercial Real Estate Group, Inc., neither party to this Lease has employed or
otherwise used any broker or agent in relation to this Lease. Lessor will
indemnify and hold Tenant harmless, and Tenant will indemnify and hold Lessor
harmless, from and against any claims for brokerage or other commissions or fees
arising out of any breach of the foregoing representation and warranty by the
respective indemnitors.

37. Notices.

Any notice under this Lease will be in writing, and will be sent by prepaid
certified mail, or by telegram confirmed by certified mail, addressed to Tenant
at the Premises, with a copy to McKesson Corporation, 1 Post Street, San
Francisco, California 94104, ATTN: Corporate Secretary, and to Lessor at 1550
Utica Avenue South, Suite 120, St. Louis Park, Minnesota 55416, or to such other
address as is

                                       28

<PAGE>   29
designated in a notice given under this Section. A notice will be deemed given
on the date mailed. Lessor's statements of Costs and other routine mailings to
tenants need not be sent by certified mail.

38. Governing Law.

The Lease will be construed under and governed by the laws of Minnesota. If any
provision of this Lease is illegal or unenforceable, it will be severable and
all other provisions will remain in force as though the severable provision had
never been included.

39. Entire Agreement.

This Lease contains the entire agreement between Lessor and Tenant regarding
the Premises. Tenant agrees that it has not relied on any statement,
representation or warranty of any person except as set out in the Lease. This
Lease may be modified only by an agreement in writing signed by Lessor and
Tenant. No surrender of the Premises, or of the remainder of the Term, will be
valid unless accepted by Lessor in writing.

40. Successors and Assigns.

All provisions of this Lease will be binding on and for the benefit of the
successors and assigns of Lessor and Tenant, except that no person or entity
holding under or through Tenant in violation of any provision of this Lease
will have any right or interest in this Lease or the Premises.

Lessor and Tenant have executed this Lease to be effective as of the date
stated in the first paragraph of this Lease.

Tenant:                                 Lessor:

McKESSON CORPORATION                    MEPC AMERICAN PROPERTIES INC.

By /s/ [ILLEGIBLE]                      By /s/ [ILLEGIBLE]
   -------------------------------        ----------------------------------
   Its Vice President                     Its Senior Vice President
       ---------------------------            ------------------------------

And                                     And /s/ [ILLEGIBLE]
    ------------------------------          --------------------------------
   Its                                    Its Vice President
       ---------------------------            ------------------------------

                                       29
<PAGE>   30
                                                                       EXHIBIT A
                                                                     PAGE 1 OF 3




                                  [FLOOR PLAN]
<PAGE>   31
                                                                       EXHIBIT A
                                                                     PAGE 2 OF 3




                                  [FLOOR PLAN]
<PAGE>   32
                                                                       EXHIBIT A
                                                                     PAGE 3 OF 3




                                  [FLOOR PLAN]
<PAGE>   33
                                    EXHIBIT B

                                      LAND


Lot 1, Block 1, Norman Center, Inc. 4th Addition, according to the recorded plat
thereof, Hennepin County, Minnesota.


<PAGE>   34

                                    EXHIBIT C

                              RULES AND REGULATIONS

1.       Tenant will not use the Premises in any manner which conflicts with any
         law, ordinance, or governmental rule or regulation now or subsequently
         in force.

2.       Tenant will not install any awnings or other attachments or structures
         on the exterior of the Building.

3.       Curtains, draperies or other window coverings will not be installed in
         the Premises without first obtaining written approval by Lessor of the
         exterior color and material.

4.       Except for microwave heating of food for employees, no food will be
         prepared or cooked in the Premises without prior written consent by
         Lessor, and the Premises will not be used for housing, lodging,
         sleeping or for any immoral or illegal purpose.

5.       Tenant will not operate or permit to be operated in the Premises any
         musical or sound producing instrument or device which can be heard
         outside the Premises.

6.       Tenant will not bring or permit to be brought into the Building any
         animals or birds.

7.       Tenant will not use any power for the operation of any equipment or
         device other than electricity provided by Lessor.

8.       Tenant will refer to Lessor all contractors or installation technicians
         rendering any service for Tenant for approval by Lessor before any
         contractual services are performed. This will include but is not
         limited to installation of telephone or telegraph equipment, electrical
         devices and attachments, and any installations affecting floors, walls,
         woodwork, trim, windows, ceilings, equipment or other portions of the
         Building.

9.       The work of the janitor or cleaning personnel after 5:00 p.m. will not
         be hindered by Tenant, and the windows may be cleaned at any time.
         Tenant will provide adequate waste and rubbish receptacles to
         facilitate cleaning services.

                                       C-1


<PAGE>   35

10.      Movement in or out of the Building of furniture or office equipment, or
         the sending or receipt by Tenant of merchandise or materials which
         requires use of elevators or stairways or movement through Building
         entrances will be done in a manner so as to avoid any damage to the
         Building. Any damage in connection with the moving or installing of
         Tenant's furniture, equipment, appliances or other articles will be
         paid for by Tenant. Subject to the provisions of this Lease, Tenant
         assumes all risk of damage to any items moved and for any injury to any
         person or property, and Tenant will indemnify Lessor against any
         resulting loss or damages.

11.      Lessor will not be responsible for any property, equipment, money or
         jewelry lost or stolen from the Premises or the public areas of the
         Building, regardless of whether or not the loss occurs when the
         Premises are locked.

12.      Lessor may designate the maximum weight and proper position of any
         heavy equipment, including safes and large files to be placed in the
         Building, and only those which in the opinion of Lessor will not damage
         the floors, structures or elevators may be moved into the Building.


13.      Lessor may permit entrance to the Premises by use of pass keys
         controlled by Lessor or its employees, contractors or service
         personnel, for the purpose of performing Lessor's janitorial services.

                                       C-2

<PAGE>   36

                                    EXHIBIT D

                                  LESSOR'S WORK

Lessor will complete the following work at its sole cost and expense.

EXTERIOR WORK

         o        Replace old light fixtures in parking lot with all new light
                  fixtures

         o        2" asphalt overlay of entire parking lot and restriping

         o        New curbing throughout lot as required

INTERIOR WORK

         o        A Linx security system with a card reader at the entrances to
                  the Building

         o        A two (2) stop 2,500 pound hydraulic passenger elevator

<PAGE>   37

                                    EXHIBIT E

                               JANITORIAL SERVICES

<TABLE>
<CAPTION>
GENERAL OFFICE                                                                  SERVICE FREQUENCY
<S>                                                                             <C>
   Empty and damp wipe ashtrays                                                       Daily

   Empty all waste receptacles and remove trash to designated area                    Daily

   Spot clean partitions and door glass                                               Daily

   Clean and polish all drinking fountains removing water marks, scale, and
   splashes on side and front                                                         Daily

   Spot clean all walls, light switches and doors                                     Daily

   Clean and sanitize all sinks and wipe daily                                        Daily

   Vacuum and spot clean all commercial
   grade carpeted floors                                                              Daily

   Dust mop all hard surface floors with treated dust mop                             Daily

   Spot mop all stains and spills                                                     Daily

   Dust all high and low surfaces within normal reach                                 Weekly

   Dust wipe all telephones including
   ear and mouth pieces                                                               Weekly

   Vacuum all soil and dust. Remove visible soil.
   Detail vacuum as scheduled.                                                        Weekly

   Damp mop entire hard surface area.                                                 Weekly

   After dust mopping the area, using a high speed machine, spray buff all hard
   surface floors.                                                                    Weekly

   Damp wipe wastebaskets.                                                            Monthly

   Machine scrub hard surface floor and apply one coat of polish. Allow to dry,
   then buff.                                                                         6x year

   Clean all ceiling diffusers                                                        Quarterly
</TABLE>

<PAGE>   38
PHG/LAS/ta
11/23/99

                              FIRST LEASE AMENDMENT

          THIS FIRST LEASE AMENDMENT (the "Amendment") is executed this ___ day
of _________________ 1999 by and between DUKE-WEEKS REALTY LIMITED PARTNERSHIP,
an Indiana limited partnership ("Landlord"), and PCS HEALTH SYSTEMS, INC., a
Delaware corporation ("Tenant").

                                   WITNESSETH:

          WHEREAS, MEPC American Properties, Inc., as predecessor in interest to
Landlord, and McKesson Corporation, as predecessor in interest to Tenant,
entered into a certain lease dated August 6, 1993 (the "Lease"), whereby Tenant
leased from Landlord certain premises consisting of approximately 45,332
rentable square feet (the "Premises") located in an office building, commonly
known as Norman Center IV, 5701 Green Valley Drive, Bloomington, Minnesota
55437; and

          WHEREAS, Landlord and Tenant desire to extend the Lease Term for a
period of thirty-six (36) months; and

          WHEREAS, Landlord and Tenant desire to amend certain provisions of the
Lease to reflect such extension;

          NOW, THEREFORE, in consideration of the foregoing premises, the mutual
covenants herein contained and each act performed hereunder by the parties,
Landlord and Tenant hereby enter into this Amendment.

          1. Incorporation of Recitals. The above recitals are hereby
incorporated into this Amendment as IF fully set forth herein.

          2. Amendment of Section 1. Definitions. Section 1 of the Lease is
hereby amended as follows:

          (c) Term is hereby extended through September 30, 2003.

          (f) Commencing October 1, 2000 "Monthly Base Rent" means the
following:

                   10/01/00--09/30/01 $47,220.83
                   10/01/01--09/30/02 $49,109.67
                   10/01/02--09/30/03 $50,998.50

          (g) "Costs" means the Tax Costs plus the Operating Costs.

          (h) "Monthly Rent" means the Monthly Base Rent plus the Costs.

          3. Amendment of Section 3. Rent. Section 3 of the Lease is hereby
amended to provide that Tenant shall pay the Monthly Rent to Landlord at NW
7210, P.O. Box 1450, Minneapolis, Minnesota 55485-7210, or such other place as
Landlord may designate, on or before the first day of each month during the
Lease Term, without demand, deduction or setoff.

          4. Amendment of Section 13. Construction of Tenant Improvements;
Alterations. Section 13 of the Lease is hereby amended by deleting paragraphs 1,
2, 3, 4 & 5 and substituting the following in lieu thereof:

                    Tenant has personally inspected the Premises and accepts the
          same "as is" without representation or warranty by Landlord of any
          kind and with the understanding that Landlord shall have no
          responsibility with respect thereto except Landlord shall install, at
          Landlord's sole cost and expense, building standard carpet within the
          Premises.

          5. Amendment of Section 28. Termination. Section 28 of the Lease is
hereby deleted in its entirety and shall be of no further force or effect.

          6. Amendment of Section 29. Extension Term. Section 29 of the Lease is
hereby deleted in its entirety and shall be of no further force or effect.

<PAGE>   39

          7. Amendment of Section 31. Landlord's Work. Section 31 of the Lease
is hereby deleted in its entirety and shall be of no further force or effect.

          8. Amendment of Section 33. Expansion. Section 33 of the Lease is
hereby deleted in its entirety and shall be of no further force or effect.

          9. Amendment of Section 34. Relocation Allowance. Section 34 of the
Lease is hereby deleted in its entirety and shall be of no further force or
effect.

          10. Amendment of Section 36. Brokers. Section 36 of the Lease is
hereby deleted and the following is substituted in lieu thereof:

                    Tenant represents and warrants that, except for Duke-Weeks
          Realty Limited Partnership, and Colliers, Pinkard, no other real
          estate broker or brokers were involved in the negotiation and
          execution of this Amendment. Tenant shall indemnify Landlord and hold
          it harmless from any and all liability for the breach of any such
          representation and warranty on its part and shall pay any compensation
          to any other broker or person who may be deemed or held to be entitled
          thereto.

          11. Amendment of Section 37. Notices. Section 37 of the Lease is
hereby amended to provide for the following notice addresses:

              Landlord:                 Duke-Weeks Realty Limited Partnership
                                        1550 Utica Avenue South, Suite 120
                                        Minneapolis, MN 55416

              Tenant:                   PCS Health Systems, Inc.
                                        5701 Green Valley Drive
                                        Bloomington, MN 55437

              With a copy to:           PCS Health Systems, Inc.
                                        Attn: Corporate Secretary
                                        1 Post Street
                                        San Francisco, CA 94104

          12. The Lease is hereby further amended by adding the following
additional section:

                    41. During the Lease Term and any extensions thereof, Tenant
          shall provide Landlord on an annual basis, within ninety (90) days
          following the end of Tenant's fiscal year, a copy of Tenant's most
          recent certified and audited financial statements prepared as of the
          end of Tenant's most recent fiscal year. Such financial statements
          shall be prepared in conformity with generally accepted accounting
          principles, consistently applied.

          13. Tenant's Representations and Warranties. The undersigned
represents and warrants to Landlord that (i) Tenant is duly organized, validly
existing and in good standing in accordance with the laws of the state under
which it was organized; (ii) all action necessary to authorize the execution of
this Amendment has been taken by Tenant; and (iii) the individual executing and
delivering this Amendment on behalf of Tenant has been authorized to do so, and
such execution and delivery shall bind Tenant. Tenant, at Landlord's request,
shall provide Landlord with evidence of such authority.

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

          15. Definitions. Except as otherwise provided herein, the capitalized
terms used in this Amendment shall have the definitions set forth in the Lease.

          16. Incorporation. This Amendment shall be incorporated into and made
a part of the Lease, and all provisions of the Lease not expressly modified or
amended hereby shall remain in full force and effect.

                                       -2-

<PAGE>   40
     IN WITNESS WHEREOF, the parties have caused this Amendment to be executed
on the day and year first written above.

                                        LANDLORD:

                                        DUKE-WEEKS REALTY LIMITED PARTNERSHIP,
                                        an Indiana limited partnership

                                        By: Duke-Weeks Realty Corporation,
                                            its general partner

                                            By:
                                               ---------------------------------
                                               James W. Gray
                                               Senior Vice President
                                               Minneapolis Office

                                        TENANT:

                                        PCS HEALTH SYSTEMS, INC.,
                                        a Delaware corporation

                                        By:
                                           -------------------------------------
                                        Printed:
                                                --------------------------------
                                        Title:
                                              ----------------------------------

STATE OF ___________     )
                         ) SS:
COUNTY OF __________     )

     Before me, a Notary Public in and for said County and State, personally
appeared _____________________________, by me known and by me known to be the
______________________________________ of PCS Health Systems, Inc., a Delaware
corporation who acknowledged the execution of the forgoing "First Lease
Amendment" on behalf of said corporation.

     WITNESS my hand and Notarial Seal this ____ of ___________________, 1999.



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


                                        ----------------------------------------
                                        (Printed Signature)

My Commission Expires:
                      ----------------
My County of Residence:
                       ---------------


                                      -3-